Atraumatic Tooth Extraction and Socket Grafting










892
34
Atraumatic Tooth Extraction
and Socket Grafting
RANDOLPH R. RESNIK AND JON B. SUZUKI
I
t is imperative that the implant clinician has a strong under-
standing of the extraction socket healing process and options
for the socket graft site preservation technique. In most cases
the extraction process will initiate a sequence of bony resorptive
morphologic changes that negatively alters the alveolar ridge. is
chapter will discuss the process of atraumatic extraction and a
decision process on when no graft is indicated and when to graft
(i.e., protocol on various bone substitutes, membranes, and heal-
ing periods).
Extraction Socket Healing
In understanding the healing process of the extraction site, the ter-
minology is often misrepresented (Box 34.1). e process of bone
repair occurs when there is injury or conditions of the bone that
cause incomplete bone volume to form in the residual ridge. e
most common conditions that cause bone repair are the absence
of a labial plate before or as a consequence of tooth extraction.
Other factors include a bony wall that is less than 1.5 mm thick
(usually the facial), exudate, gross apical pathology, or excessive
heat from a dental drill during root extraction.
e tooth socket with five bony walls (i.e., mesial, distal, buc-
cal, lingual, and apical) will heal by bone regeneration (Fig. 34.1).
e process of bone regeneration heals by secondary intention,
and bone healing in many aspects is similar to secondary intention
soft tissue healing. e healing sequence in both hard and soft
tissue includes inammation, epithelialization, fibroplasia, and
remodeling. However, socket healing presents unique microvas-
cular features and a sequential pattern of bone formation before
remodeling.
Numerous authors in the literature have proposed the healing
sequence and various stages of bone regeneration after a tooth is
extracted with a healthy surrounding alveolus.
Stage 1: Granulation Stage: After a tooth is extracted, an ini-
tial clot forms within the socket which consists of a ‘coagulum’’
of red and white blood cells. At approximately the third day, the
coagulum is slowly replaced by highly vascular granulation tissue.
e blood clot begins to shrink, and capillaries form sinusoids and
granulation tissue, starting from the socket apex and spreading
laterally and crestally along the socket walls. Granulation tissue
replaces the clot over a 4-to 5-day period.
1, 2
Stage 2: Initial Angiogenic Stage: e initial angiogenic stage
starts approximately a week after extraction. is stage develops
from the broken ends of blood vessels in the residual periodon-
tal ligament covering the cribriform plate. Blood plasma leaks
from the broken vessels, and immature broblasts aggregate at
the plasma-rich regions. Fibroplasia begins early in the sequence
during the rst week as a result of the ingrowth of capillaries and
broblasts. White blood cells kill bacteria and begin to dissolve
foreign bodies and bone fragments. With few exceptions the
angiogenesis begins at the bottom of the socket because this area
is not severely injured during the extraction and has the greatest
source of blood vessels.
3
Stage 3: Early Bone Formation Stage: is stage starts
approximately three to four weeks after extraction. e granula-
tion tissue gradually is replaced by connective tissue (collagen
bers, spindle shaped broblasts). e capillary activity begins
the early phases of trabeculae development. is capillary activ-
ity is initiated at the socket apex, and trabeculae of woven bone
growth will occur following the formation of blood vessels. Dur-
ing this stage, the cortical bone of the crestal area of the socket
will start to resorb, along with the interseptal regions and the
thinner facial plate.
4
Stage 4: Bone Growth Stage: e bone growth stage starts
at approximately four to six weeks after the extraction. is
period demonstrates the greatest sinusoid formation activity.
e forming trabeculae of woven bone rst start from the bot-
tom of the socket after the meshwork of newly formed anasto-
mosing sinusoidal capillaries. Bone formation is more rapid at
this point, creating a three-dimensional lattice pattern of woven
bone. New bone trabeculae form on the walls and approxi-
mately two-thirds of the socket is lled at four – ve weeks.
At this stage, the center of the socket is primarily composed of
woven bone. e more-organized lamellar bone starts to form
from the lining of the socket, moving toward the center. At
approximately 6 weeks, bone trabeculae almost completely ll
the socket.
5
Stage 5: Bone Reorganization Stage: e bone reorganization
stage starts at about 6 weeks after extraction. Usually complete
epithelial closure of the socket is completed by this time. e pri-
mary bone trabeculae remodel to form thicker secondary cancel-
lous bone. is process always begins at the apex of the extraction
socket. At approximately 60 days, woven bone has completely
bridged the defect and at 90 days, woven bone is resorbed by
osteoclasts which is replaced by lamellar bone. e bridged woven
bone is usually completely remodeled to lamellar bone by 16

893
CHAPTER 34 Atraumatic Tooth Extraction and Socket Grafting
weeks and most osteogenic activity is complete at this time. A new
periosteum is established by 180 days.
6,7,8
e timing for these stages varies among individuals and clin-
ical situations. e number of bony walls around the socket and
size of the alveolus greatly inuence the regeneration process.
In general, larger molar extraction sites (i.e. molar) take lon-
ger to completely form bone compared with smaller-diameter
anterior sites. Although the period of regeneration for an extrac-
tion socket is variable, the clinical sign that the socket regenera-
tion is complete is when the radiographic lamina dura (which
represents the cribriform plate) is no longer present. is heal-
ing period usually takes between 3 to 6 months, dependent on
tooth size, root number, and extent of trauma during the extrac-
tion (Fig. 34.2).
Importance of the Buccal Plate
One of the most important factors in the regeneration and repair
of bone is the buccal plate. e buccal plate of bone is more sus-
ceptible to bone loss. Studies have shown the buccal plate may
lose up to 56% horizontal bone loss and 30% vertical bone loss
within the rst year after extraction.
9,10
In addition, when the
buccal plate is thicker, the ridge tends to resorb less. e buccal
plate is also more susceptible to trauma. When iatrogenic buccal
plate damage occurs, the socket no longer heals by regeneration,
however will heal by repair. is is usually a slower healing process
and more unpredictable (Fig. 34.3).
Atraumatic Tooth Extraction
Theory of Atraumatic Tooth Extraction
ere exists a full array of reasons teeth are deemed unrestorable;
periodontal, endodontic, prosthetic, or orthodontic failures. Once
the extraction of a natural tooth is indicated, methods to maintain
or obtain the surrounding hard and soft tissues are indicated. It is
the primary goal of the implant clinician to extract the nonrestor-
able tooth while minimizing associated trauma and maintaining
the hard and soft tissue.
The atraumatic tooth extraction technique and socket graft-
ing has become a popular procedure in implant dentistry. The
process of atraumatic tooth extraction and preservation of soft
and hard tissues begins with the surrounding soft tissue. The
cells of the inner layer of the periosteum are responsible for
bone remodeling. When the bone volume is ideal, the peri-
osteum should be minimally reflected in preservation of the
blood supply. However, the periosteum can also be a limiting
factor in the volume of bone formation. When the periosteum
is separated from the bone graft by a barrier membrane, more
volume of bone is regenerated. The periosteum helps bone
remodeling or bone repair, but may also limit bone modeling
and regeneration.
Atraumatic Tooth Extraction Technique
Many techniques and protocols exist for removing teeth; however,
some basic principles should be applied to all extractions.
Severing the Connective Tissue Fibers
e soft tissue drape surrounding the teeth is aected by the
reection of the periosteum and often shrinks to adapt to the
residual ridge form. In fact, the soft tissue is more labile to
the trauma and reection of the tissues than the hard tissues.
erefore the sulcular and surrounding soft tissue should ide-
ally remain undisturbed during tooth extraction to prevent fur-
ther dimensional loss. e extraction of a natural tooth begins
with an incision within the sulcus, preferably with a thin scalpel
blade or a blunt periotome. e incision should encompass the
entire tooth (i.e., 360 degrees around the tooth) to sever the
connective tissue attachment fibers above the bone (Fig. 34.4).
ere exist 13 dierent connective tissue fiber groups around
a tooth, of which 6 directly insert into the cementum of the
tooth above the bone. If these fibers are not severed before the
extraction, trauma to the soft tissue is imminent. e soft tissue
may tear, causing a delay in the healing process and increases
bleeding (Fig. 34.5).
Minimizing Soft Tissue Reflection
e soft tissue should ideally be minimally reected, because soft
tissue retraction and shrinkage during initial healing are more
evident, especially in the interdental papilla region. Usually a ap
is raised when the buccal plate is not intact or surgical extrac-
tion of the tooth is indicated. If a tissue ap needs to be raised,
an envelope ap (no vertical extension) is used. e vertical
Bone remodeling—the replacement of old bone tissue by new bone
tissue; natural phenomena to maintain healthy bone mass
Bone modeling—adapts bone size and shape to stress or loading
Bone repair—a physiologic process in which the body facilitates the
repair of a bone fracture
Bone regeneration—requires the use of surgical protocols that enable
bone growth within deficient sites, using the principles of osteogenesis,
osteoinduction, and osteoconduction
Socket restoration versus preservation—difficult to differentiate;
both terms are used
Bone is restored in the socket (generally for the placement of an implant)
Bone preservation indicates long-term stability of the alveolar ridge
BOX
34.1
Bone Healing Denitions
Fig. . The treatment plan and protocol for a post-extraction socket
is dictated by five bony walls: mesial (M), distal (D), buccal (B), lingual (L),
and apical (A).

ABC
DE
Fig. . The Five Stages of Extraction Site Healing: (A) Granulation Stage: Initial blood clot forms and is
gradually replaced with granulation tissue, (B) Initial Angiogenic Stage: Blood vessel formation integrates into the
graft which starts at approximately one week, (C) Early Bone Formation Stage: At approximately 3-4 weeks, the
granulation tissue is replaced by connective tissue. Woven bone starts to form at apex, (D) Bone Growth Stage:
Greater woven bone growth continues as the center of the socket is primarily woven bone. Lamellar bone starts
to form around the apex and lining of the socket, (E) Bone Reorganization Stage: Complete epithelial closure
is usually complete by week 6. Woven bone is gradually replaced by lamellar and is complete by 16 weeks.
Fig. . The buccal plate is susceptible to fracture during extraction
because the buccal plate is usually thinner than the lingual plate.
Fig. . The extraction of the tooth begins with a scalpel to incise the
sulcular connective tissue fibers above the bone, which are attached to the
cementum of the tooth.

895
CHAPTER 34 Atraumatic Tooth Extraction and Socket Grafting
incisions may compromise the blood supply and may delay the
healing of the area. Whenever the periosteum is reected, the
cells are injured and need to regenerate before the remodeling
process begins. e cortical bone receives more than 80% of its
arterial blood supply and facilitates 100% of its venous blood
return through the periosteum.
11
In some situations reection of
the tissue is necessary such as the use of bone-supported surgical
templates (Fig. 34.6).
Evaluating the Anatomy of the Tooth to Be Extracted
e next step in the atraumatic extraction process is to evalu-
ate the crown and root anatomy. is is especially important
for divergent, multirooted teeth. If the roots of the tooth to be
extracted are divergent, they should be sectioned and removed as
individual units, rather than risking fracture of the roots or sur-
rounding bone (Fig. 34.7). When the roots are fractured, there
is an increased risk for bone fracture/removal to retrieve them. If
bone removal around the tooth is necessary (because the tooth
is fractured or decayed to the bony crest), it ideally should be at
the expense of the lingual alveolus, not the more labial bone. e
buccal plate of bone is almost always thinner than the lingual
plate. Another option to reduce trauma when taking out teeth
is modication of the contact (proximal) areas. When adjacent
teeth are present the pathway of removal is often obstructed by
the position of the adjacent tooth. If the tooth to be extracted
is not reduced (i.e., mesial and distally), instruments or pressure
may chip the enamel (or restoration) of the adjacent tooth and
may cause the extraction of the tooth to take an altered pathway
of removal, which is more likely to fracture the roots, bone, or
both (Fig. 34.8).
Atraumatic Removal of the Tooth
Basic Principles. Biomechanic concepts have been used to
extract teeth for thousands of years and date back to the days of
Aristotle (384–322 BCE),
12
who described the mechanics of the
extraction forceps, including the advantages of “two levers acting
in contrary sense having a single fulcrum.” is was 100 years
before Archimedes reported on the principles of the lever. Pierre
Fauchard
13
(1678–1761) is credited with being the pioneer of
scientific dentistry and gave specific instructions for extracting
teeth using a dental elevator, a “pelican,” or pincers (forceps).
He describes loosening the tooth with an elevator, then using
the claw of the “pelican” (invented by Chauliac
14
in the four-
teenth century). e pelican handle was positioned both on the
tooth and on the gum below the tooth while it was rocked back
and forth (which he called “shaking”) before the extraction. Taft
described a similar technique using the dental key, which had
Fig. . Illustration depicting the soft tissue attachment to a natural tooth.
Thirteen different fibers insert into the tooth root and if not severed during
the atraumatic extraction technique, hard and soft tissue damage will result.
Fig. . When a bone supported and reduction guide is indicated, a
more extensive reflection is required for access and seating of the template.
AB
C
D
Fig. . Atraumatic Extraction: (A) Mandibular first molar to be extracted, (B) Proximal contacts removed to allow for easier extraction, (C) Sectional of
roots to minimize trauma, (D) Use of periotome to remove roots.

896
PART VII Soft and Hard Tissue Rehabilitation
left and right claws that provided twisting and rocking in both
directions.
15
is allowed the tooth to be loosened sufficiently
to be pulled from the socket with “pincers” (forceps). Modern
extraction forceps date from Tomes in 1840, with the develop-
ment of the anatomic forceps, complete with a handle and beak
to fit the neck of the tooth.
Biomechanics of Tooth Removal. e principle of the den-
tal elevator is also not a modern development. Abulkasim (AD
1050–1122) was the first to apply a single lever (elevator) under
the tooth to force it from its “bed.” It was improved by Ambroise
Paré in the sixteenth century to lift out the tooth before using the
pelican. Although these biomechanical methods to remove teeth
are eective, a review of the biomechanical principles is in order to
decrease the trauma during the tooth extraction process.
e term “simple machine” is often used to describe basic
devices that increase the amount of force applied (e.g., the lever,
inclined plane, wheel, screw, pulley). ey each transmit or mod-
ify force or torque. e most common devices used in the extrac-
tion of teeth include levers and inclined planes.
e wedge is technically a moving double inclined plane,
which overcomes a large resistance by applying a relatively
smaller force than the load necessary to move an object. e
mechanical advantage of a wedge depends on the ratio of its
length to its thickness. A short wedge with a wide angle moves
an object faster; however, it requires more force than a long
wedge with a smaller angle. Dental elevators use the mechanical
advantage of a wedge to initiate the luxation of teeth for their
removal (Figs. 34.9 and 34.10).
Periotomes. Periotomes are usually longer and thinner wedges
compared with dental elevators and often are used to begin the atrau-
matic extraction process. Periotomes may be used in a similar manner
for extraction of intact teeth or removal of retained root fragments.
Technique.
1. e long axis of the periotome blade should be inserted into
the interproximal region along the root long axis (to protect the
facial plate of bone), with the tip of the periotome blade located
within the crest of the alveolar bone. e instrument is then
pushed or tapped with a mallet into the periodontal ligament
space along the mesial and distal root, severing the periodontal
A
B
Fig. . (A) The maxillary lateral incisor requires extraction. The path-
way of removal may restrict the extraction or chip an adjacent tooth. (B)
The distal portion of the lateral incisor was reduced to allow the tooth to
move distal, which allows pressure to the periodontal ligament and bone.
In addition, there is less risk for adjacent tooth damage.
Fig. . Improper Extraction Technique: may often lead to retained
fractured root tips or loss of buccal plate.
Risk of
fractured
buccal
plate
Fig. . Conventional extraction forceps often will result in the frac-
ture the buccal plate leading to a compromised future implant site.

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89234Atraumatic Tooth Extraction and Socket GraftingRANDOLPH R. RESNIK AND JON B. SUZUKIIt is imperative that the implant clinician has a strong under-standing of the extraction socket healing process and options for the socket graft site preservation technique. In most cases the extraction process will initiate a sequence of bony resorptive morphologic changes that negatively alters the alveolar ridge. is chapter will discuss the process of atraumatic extraction and a decision process on when no graft is indicated and when to graft (i.e., protocol on various bone substitutes, membranes, and heal-ing periods).Extraction Socket HealingIn understanding the healing process of the extraction site, the ter-minology is often misrepresented (Box 34.1). e process of bone repair occurs when there is injury or conditions of the bone that cause incomplete bone volume to form in the residual ridge. e most common conditions that cause bone repair are the absence of a labial plate before or as a consequence of tooth extraction. Other factors include a bony wall that is less than 1.5 mm thick (usually the facial), exudate, gross apical pathology, or excessive heat from a dental drill during root extraction.e tooth socket with five bony walls (i.e., mesial, distal, buc-cal, lingual, and apical) will heal by bone regeneration (Fig. 34.1). e process of bone regeneration heals by secondary intention, and bone healing in many aspects is similar to secondary intention soft tissue healing. e healing sequence in both hard and soft tissue includes inammation, epithelialization, fibroplasia, and remodeling. However, socket healing presents unique microvas-cular features and a sequential pattern of bone formation before remodeling.Numerous authors in the literature have proposed the healing sequence and various stages of bone regeneration after a tooth is extracted with a healthy surrounding alveolus.Stage 1: Granulation Stage: After a tooth is extracted, an ini-tial clot forms within the socket which consists of a ‘‘coagulum’’ of red and white blood cells. At approximately the third day, the coagulum is slowly replaced by highly vascular granulation tissue. e blood clot begins to shrink, and capillaries form sinusoids and granulation tissue, starting from the socket apex and spreading laterally and crestally along the socket walls. Granulation tissue replaces the clot over a 4-to 5-day period.1, 2Stage 2: Initial Angiogenic Stage: e initial angiogenic stage starts approximately a week after extraction. is stage develops from the broken ends of blood vessels in the residual periodon-tal ligament covering the cribriform plate. Blood plasma leaks from the broken vessels, and immature broblasts aggregate at the plasma-rich regions. Fibroplasia begins early in the sequence during the rst week as a result of the ingrowth of capillaries and broblasts. White blood cells kill bacteria and begin to dissolve foreign bodies and bone fragments. With few exceptions the angiogenesis begins at the bottom of the socket because this area is not severely injured during the extraction and has the greatest source of blood vessels.3Stage 3: Early Bone Formation Stage: is stage starts approximately three to four weeks after extraction. e granula-tion tissue gradually is replaced by connective tissue (collagen bers, spindle shaped broblasts). e capillary activity begins the early phases of trabeculae development. is capillary activ-ity is initiated at the socket apex, and trabeculae of woven bone growth will occur following the formation of blood vessels. Dur-ing this stage, the cortical bone of the crestal area of the socket will start to resorb, along with the interseptal regions and the thinner facial plate.4Stage 4: Bone Growth Stage: e bone growth stage starts at approximately four to six weeks after the extraction. is period demonstrates the greatest sinusoid formation activity. e forming trabeculae of woven bone rst start from the bot-tom of the socket after the meshwork of newly formed anasto-mosing sinusoidal capillaries. Bone formation is more rapid at this point, creating a three-dimensional lattice pattern of woven bone. New bone trabeculae form on the walls and approxi-mately two-thirds of the socket is lled at four – ve weeks. At this stage, the center of the socket is primarily composed of woven bone. e more-organized lamellar bone starts to form from the lining of the socket, moving toward the center. At approximately 6 weeks, bone trabeculae almost completely ll the socket.5Stage 5: Bone Reorganization Stage: e bone reorganization stage starts at about 6 weeks after extraction. Usually complete epithelial closure of the socket is completed by this time. e pri-mary bone trabeculae remodel to form thicker secondary cancel-lous bone. is process always begins at the apex of the extraction socket. At approximately 60 days, woven bone has completely bridged the defect and at 90 days, woven bone is resorbed by osteoclasts which is replaced by lamellar bone. e bridged woven bone is usually completely remodeled to lamellar bone by 16 893CHAPTER 34 Atraumatic Tooth Extraction and Socket Graftingweeks and most osteogenic activity is complete at this time. A new periosteum is established by 180 days.6,7,8e timing for these stages varies among individuals and clin-ical situations. e number of bony walls around the socket and size of the alveolus greatly inuence the regeneration process. In general, larger molar extraction sites (i.e. molar) take lon-ger to completely form bone compared with smaller-diameter anterior sites. Although the period of regeneration for an extrac-tion socket is variable, the clinical sign that the socket regenera-tion is complete is when the radiographic lamina dura (which represents the cribriform plate) is no longer present. is heal-ing period usually takes between 3 to 6 months, dependent on tooth size, root number, and extent of trauma during the extrac-tion (Fig. 34.2).Importance of the Buccal PlateOne of the most important factors in the regeneration and repair of bone is the buccal plate. e buccal plate of bone is more sus-ceptible to bone loss. Studies have shown the buccal plate may lose up to 56% horizontal bone loss and 30% vertical bone loss within the rst year after extraction.9,10 In addition, when the buccal plate is thicker, the ridge tends to resorb less. e buccal plate is also more susceptible to trauma. When iatrogenic buccal plate damage occurs, the socket no longer heals by regeneration, however will heal by repair. is is usually a slower healing process and more unpredictable (Fig. 34.3). Atraumatic Tooth ExtractionTheory of Atraumatic Tooth Extractionere exists a full array of reasons teeth are deemed unrestorable; periodontal, endodontic, prosthetic, or orthodontic failures. Once the extraction of a natural tooth is indicated, methods to maintain or obtain the surrounding hard and soft tissues are indicated. It is the primary goal of the implant clinician to extract the nonrestor-able tooth while minimizing associated trauma and maintaining the hard and soft tissue.The atraumatic tooth extraction technique and socket graft-ing has become a popular procedure in implant dentistry. The process of atraumatic tooth extraction and preservation of soft and hard tissues begins with the surrounding soft tissue. The cells of the inner layer of the periosteum are responsible for bone remodeling. When the bone volume is ideal, the peri-osteum should be minimally reflected in preservation of the blood supply. However, the periosteum can also be a limiting factor in the volume of bone formation. When the periosteum is separated from the bone graft by a barrier membrane, more volume of bone is regenerated. The periosteum helps bone remodeling or bone repair, but may also limit bone modeling and regeneration. Atraumatic Tooth Extraction TechniqueMany techniques and protocols exist for removing teeth; however, some basic principles should be applied to all extractions.Severing the Connective Tissue Fiberse soft tissue drape surrounding the teeth is aected by the reection of the periosteum and often shrinks to adapt to the residual ridge form. In fact, the soft tissue is more labile to the trauma and reection of the tissues than the hard tissues. erefore the sulcular and surrounding soft tissue should ide-ally remain undisturbed during tooth extraction to prevent fur-ther dimensional loss. e extraction of a natural tooth begins with an incision within the sulcus, preferably with a thin scalpel blade or a blunt periotome. e incision should encompass the entire tooth (i.e., 360 degrees around the tooth) to sever the connective tissue attachment fibers above the bone (Fig. 34.4). ere exist 13 dierent connective tissue fiber groups around a tooth, of which 6 directly insert into the cementum of the tooth above the bone. If these fibers are not severed before the extraction, trauma to the soft tissue is imminent. e soft tissue may tear, causing a delay in the healing process and increases bleeding (Fig. 34.5). Minimizing Soft Tissue Reflectione soft tissue should ideally be minimally reected, because soft tissue retraction and shrinkage during initial healing are more evident, especially in the interdental papilla region. Usually a ap is raised when the buccal plate is not intact or surgical extrac-tion of the tooth is indicated. If a tissue ap needs to be raised, an envelope ap (no vertical extension) is used. e vertical • Bone remodeling—the replacement of old bone tissue by new bone tissue; natural phenomena to maintain healthy bone mass • Bone modeling—adapts bone size and shape to stress or loading • Bone repair—a physiologic process in which the body facilitates the repair of a bone fracture • Bone regeneration—requires the use of surgical protocols that enable bone growth within deficient sites, using the principles of osteogenesis, osteoinduction, and osteoconduction • Socket restoration versus preservation—difficult to differentiate; both terms are used • Bone is restored in the socket (generally for the placement of an implant) • Bone preservation indicates long-term stability of the alveolar ridge • BOX 34.1 Bone Healing Denitions• Fig. . The treatment plan and protocol for a post-extraction socket is dictated by five bony walls: mesial (M), distal (D), buccal (B), lingual (L), and apical (A). ABCDE• Fig. . The Five Stages of Extraction Site Healing: (A) Granulation Stage: Initial blood clot forms and is gradually replaced with granulation tissue, (B) Initial Angiogenic Stage: Blood vessel formation integrates into the graft which starts at approximately one week, (C) Early Bone Formation Stage: At approximately 3-4 weeks, the granulation tissue is replaced by connective tissue. Woven bone starts to form at apex, (D) Bone Growth Stage: Greater woven bone growth continues as the center of the socket is primarily woven bone. Lamellar bone starts to form around the apex and lining of the socket, (E) Bone Reorganization Stage: Complete epithelial closure is usually complete by week 6. Woven bone is gradually replaced by lamellar and is complete by 16 weeks.• Fig. . The buccal plate is susceptible to fracture during extraction because the buccal plate is usually thinner than the lingual plate.• Fig. . The extraction of the tooth begins with a scalpel to incise the sulcular connective tissue fibers above the bone, which are attached to the cementum of the tooth. 895CHAPTER 34 Atraumatic Tooth Extraction and Socket Graftingincisions may compromise the blood supply and may delay the healing of the area. Whenever the periosteum is reected, the cells are injured and need to regenerate before the remodeling process begins. e cortical bone receives more than 80% of its arterial blood supply and facilitates 100% of its venous blood return through the periosteum.11 In some situations reection of the tissue is necessary such as the use of bone-supported surgical templates (Fig. 34.6). Evaluating the Anatomy of the Tooth to Be Extractede next step in the atraumatic extraction process is to evalu-ate the crown and root anatomy. is is especially important for divergent, multirooted teeth. If the roots of the tooth to be extracted are divergent, they should be sectioned and removed as individual units, rather than risking fracture of the roots or sur-rounding bone (Fig. 34.7). When the roots are fractured, there is an increased risk for bone fracture/removal to retrieve them. If bone removal around the tooth is necessary (because the tooth is fractured or decayed to the bony crest), it ideally should be at the expense of the lingual alveolus, not the more labial bone. e buccal plate of bone is almost always thinner than the lingual plate. Another option to reduce trauma when taking out teeth is modication of the contact (proximal) areas. When adjacent teeth are present the pathway of removal is often obstructed by the position of the adjacent tooth. If the tooth to be extracted is not reduced (i.e., mesial and distally), instruments or pressure may chip the enamel (or restoration) of the adjacent tooth and may cause the extraction of the tooth to take an altered pathway of removal, which is more likely to fracture the roots, bone, or both (Fig. 34.8). Atraumatic Removal of the ToothBasic Principles. Biomechanic concepts have been used to extract teeth for thousands of years and date back to the days of Aristotle (384–322 BCE),12 who described the mechanics of the extraction forceps, including the advantages of “two levers acting in contrary sense having a single fulcrum.” is was 100 years before Archimedes reported on the principles of the lever. Pierre Fauchard13 (1678–1761) is credited with being the pioneer of scientific dentistry and gave specific instructions for extracting teeth using a dental elevator, a “pelican,” or pincers (forceps). He describes loosening the tooth with an elevator, then using the claw of the “pelican” (invented by Chauliac14 in the four-teenth century). e pelican handle was positioned both on the tooth and on the gum below the tooth while it was rocked back and forth (which he called “shaking”) before the extraction. Taft described a similar technique using the dental key, which had • Fig. . Illustration depicting the soft tissue attachment to a natural tooth. Thirteen different fibers insert into the tooth root and if not severed during the atraumatic extraction technique, hard and soft tissue damage will result.• Fig. . When a bone supported and reduction guide is indicated, a more extensive reflection is required for access and seating of the template.ABCD• Fig. . Atraumatic Extraction: (A) Mandibular first molar to be extracted, (B) Proximal contacts removed to allow for easier extraction, (C) Sectional of roots to minimize trauma, (D) Use of periotome to remove roots. 896PART VII Soft and Hard Tissue Rehabilitationleft and right claws that provided twisting and rocking in both directions.15 is allowed the tooth to be loosened sufficiently to be pulled from the socket with “pincers” (forceps). Modern extraction forceps date from Tomes in 1840, with the develop-ment of the anatomic forceps, complete with a handle and beak to fit the neck of the tooth. Biomechanics of Tooth Removal. e principle of the den-tal elevator is also not a modern development. Abulkasim (AD 1050–1122) was the first to apply a single lever (elevator) under the tooth to force it from its “bed.” It was improved by Ambroise Paré in the sixteenth century to lift out the tooth before using the pelican. Although these biomechanical methods to remove teeth are eective, a review of the biomechanical principles is in order to decrease the trauma during the tooth extraction process.e term “simple machine” is often used to describe basic devices that increase the amount of force applied (e.g., the lever, inclined plane, wheel, screw, pulley). ey each transmit or mod-ify force or torque. e most common devices used in the extrac-tion of teeth include levers and inclined planes.e wedge is technically a moving double inclined plane, which overcomes a large resistance by applying a relatively smaller force than the load necessary to move an object. e mechanical advantage of a wedge depends on the ratio of its length to its thickness. A short wedge with a wide angle moves an object faster; however, it requires more force than a long wedge with a smaller angle. Dental elevators use the mechanical advantage of a wedge to initiate the luxation of teeth for their removal (Figs. 34.9 and 34.10). Periotomes. Periotomes are usually longer and thinner wedges compared with dental elevators and often are used to begin the atrau-matic extraction process. Periotomes may be used in a similar manner for extraction of intact teeth or removal of retained root fragments.Technique. 1. e long axis of the periotome blade should be inserted into the interproximal region along the root long axis (to protect the facial plate of bone), with the tip of the periotome blade located within the crest of the alveolar bone. e instrument is then pushed or tapped with a mallet into the periodontal ligament space along the mesial and distal root, severing the periodontal AB• Fig. . (A) The maxillary lateral incisor requires extraction. The path-way of removal may restrict the extraction or chip an adjacent tooth. (B) The distal portion of the lateral incisor was reduced to allow the tooth to move distal, which allows pressure to the periodontal ligament and bone. In addition, there is less risk for adjacent tooth damage.• Fig. . Improper Extraction Technique: may often lead to retained fractured root tips or loss of buccal plate.Risk offracturedbuccalplate• Fig. . Conventional extraction forceps often will result in the frac-ture the buccal plate leading to a compromised future implant site. 897CHAPTER 34 Atraumatic Tooth Extraction and Socket Graftingligament immediately below the alveolar crest and wedging the tooth against the opposing cribriform plate (Fig. 34.11A). e periotome should never be used on the facial plate because this may damage the host bone. 2. A period of 10 to 30 seconds is allowed to elapse while the instrument is in place. is allows biomechanical creep to occur to the ligament and reduces its strength, and because the tooth is pushed against the opposing alveolus, it also will begin to expand the bone. is process is much more eective when there is no adjacent tooth contact. Reducing the mesial and distal proximal contacts of the tooth to be extracted not only decreases the risk for damage to the adjacent tooth crown, but also aids in the extraction hopeless tooth. 3. e periotome is then pushed farther down into the periodon-tal ligament space toward the root apex, often using a mallet and light tapping force. is process continues along the crestal third of the tooth. At the completion of this step the tooth is often slightly mobile (Fig. 34.11B). 4. Once the periotome is used as a moving wedge, it may then be converted to a lever (Fig. 34.11C). e blade of the periotome is often 3 to 4 mm wide. When the handle is rotated, one side of the periotome is applied to the tooth root, the other side to the cribriform plate, and the width of the “wedge” is now the length of a lever, which magnifies the rotation force (moment). e rotation of the periotome handle increases both tooth mobility and the force against the opposite cortical plate to further expand it within physiologic limits. 5. A single-rooted tooth is most often tapered. As the periotome is tapped further apically toward the cribriform plate, it is slightly rotated. Because the socket is tapered, the lateral force on one side of the tooth is converted to a coronal direction force on the other side and the root is pushed out of the socket. As a result the periotome may now be pushed farther apical, toward the root apex. When time elapses between each force application, the tooth may even slide up and completely out of the socket. Additional time and elevation may be required if significant tooth mobility is not achieved. Use of Conventional Forceps. Traditional dental forceps should not be applied to the tooth until significant tooth mobility is achieved. Once the wedge and lever action of the dental eleva-tor is applied to a tooth, most often dental forceps are used to ultimately grasp and deliberately rock the tooth back and forth, and to rotate it as much as conditions will allow. e combination of these tooth movements expands the bony socket and separates the periodontal ligaments. As a consequence the tooth may be removed (Fig. 34.11D). Conventional dental forceps are actually two first-class levers connected with a hinge. e forces applied to the forceps handles are the long side of the lever and the beaks on the tooth are the short side of the lever, with the hinge acting as a fulcrum. e force on the handles is magnified to allow the ACBD• Fig. . (A) A periotome is inserted along the tooth root on the mesial and pushed (or tapped with a mallet) to wedge the tooth against the opposing cribriform plate. A similar process is performed on the distal interpositional region of the tooth root. (B) Once the periotome acts as a wedge and is in place for 10 to 30 seconds, it is tapped (with a mallet) farther down along the mesial and distal interproximal root sur-face. (C) The periotome is converted into a lever by rotating the handle several degrees, which magnifies the force against the root. The tooth becomes slightly mobile at this stage. (D) A traditional dental forceps may remove the tooth after initial mobility is created by the periotome. 898PART VII Soft and Hard Tissue Rehabilitationbeaks of the forceps to grasp the tooth with great force. None of the force on the forceps handles is used to extract the tooth. Rather, the increased force on the forceps beaks often crushes or fractures the tooth. e forceps hold the tooth, and the surgeon’s hand, wrist, and arm are used to move and extract the tooth. is action would be similar to forcibly pulling a bottle cap o a bottle or pulling a nail from a piece of wood using only a pair of pliers. Alternative Extraction Forceps. e principles of biomechanics are the basis for the development of a dierent type of dental for-ceps called Physics Forceps (Golden-Misch Instruments, Detroit, Mich.). A moment of force in physics represents the magnitude of force applied to a rotational system at a distance from the axis of rotation. e principle of moment M is derived from Archimedes’ discovery of the operating principle of the lever and is defined asM = rFwhere F is the applied force and r is the distance from the force applied to the object. e concept of a moment arm is key to the operation of the lever, which is capable of generating mechani-cal advantage. is means that the force applied to an object is aected by the length of the lever arms. e lever arm is the dis-tance from the force input to the fulcrum or from the fulcrum to the force output.e Physics Forceps is a dental extractor that uses first-class lever mechanics. One beak of the forcep is connected to a “bum-per,” which acts as a fulcrum during the extraction. e bumper is placed most often on the facial aspect of the dental alveolus, at or above the mucogingival junction. e second beak of the forcep is positioned as low as practical on the tooth root, most often on the palatal (lingual) into the gingival sulcus.Once the forcep is in position around the tooth root, no squeezing pressure is applied to the tooth. Instead, the handles, once in position, are rotated as one unit facially for a few degrees and stopped for approximately 30-60 seconds (Fig. 34.12). e torque force generated on the tooth, periodontal ligament, and bone is related to the length of the handle to the bumper (8 cm), divided by the distance from the bumper to the forceps beak (1 cm). As a result a force on the handle connected to the bumper will increase the force on the tooth periodontal ligament and bone by eight times. No force is required to be placed on the forceps beak, BAC D• Fig. . The Physics (Atraumatic) Forceps. (A) A “bumper” (one beak) is placed on the facial of the tooth to be extracted at or below the mucogingival junction. The second beak is placed on the lingual, engaging the tooth root. The handles of the forceps act as a lever to rotate (avulse) the tooth from the socket. The bumper is placed below the tooth, usually at or above the mucogingival junction. The beak is placed low on the tooth root in the gingival sulcus. (B) Once the forcep is in position on the tooth root, the Physics Forceps is used as one unit (no squeezing of the handles). A few degrees of rotation to the facial places moment force on the tooth, which is held for 30 to 60 seconds. (C) Once the tooth releases from the socket, it is removed with a pincer-like device (e.g., pick-ups, extraction forceps, hemostat). (D) After removal of the tooth root, inspection of the root is completed to verify complete removal. 899CHAPTER 34 Atraumatic Tooth Extraction and Socket Graftingwhich is on the tooth. erefore the tooth does not split, crush, or fracture. e 30-60 seconds of constant force cause biomechani-cal creep into the bone and periodontal ligament. Once creep has expanded and weakened the periodontal ligament and bone, the forceps handle may be slowly rotated another few degrees. is usually releases and elevates the tooth a few millimeters from the socket within an additional 10 seconds. At this point the tooth is loose and ready to be removed from the socket using any pincer-like device (e.g., pick-ups, an extraction forceps, a hemostat).e extraction of a tooth using the Physics Forceps is similar to the removal of a nail from wood with use of a carpenter’s ham-mer (instead of pliers). e handle of the hammer is a lever, and the beaks of the hammer fit under the head of a nail (they do not squeeze the head). e hammer head acts as a fulcrum. A rota-tional force applied to the hammer handle magnifies the force by the length of the handle, and the nail is elevated from the wood. Unlike a nail in wood, which is parallel and has friction for its full length, a tooth is tapered. erefore after it is elevated a few mil-limeters, the periodontal ligament fibers are broken, and the tooth may be easily removed, without additional rotational force. is is important to note, because further rotational force on the forceps may fracture the facial plate of bone.Creep is a phenomenon whereby a material continues to change shape over time under a constant load. In a tooth extrac-tion, creep may occur to bone and the periodontal ligament. Reilly established the creep curve of bone, whereby under a con-stant load of 60 MPa, the bone over time responds in three dier-ent stages.12 e majority of bone changes occur within the first minute, whereby the initial strain of bone (the change of length divided by the original length) is modified. e greater the force, the greater the deformation of the bone. is process allows the tooth socket to expand and the tooth to exit the socket. A second-ary creep curve allows the bone to further deform when the force is applied for 1 to 5 minutes. e longer the time, the greater the deformation. However, the secondary deformation is only a 10% to 20% dierence compared with the initial strain over the first minute. Eventually the bone will fracture if the load is applied over a longer time frame, representing creep rupture.e creep curve of the periodontal complex is similar to the creep curve of the bone, whereby the constant load on a tooth over time increases the strain and decreases the strength of the periodontal complex. erefore the clinician should not underes-timate the values of time and constant force to the tooth ligament and bone in the extraction process. Socket Debridement After ExtractionOnce the tooth is extracted, the tooth socket should be thoroughly debrided to remove all remnants of the periodontal ligament and any other soft tissue debris (e.g., granulation tissue). In addition, all fibrous tissue from periodontal disease or endodontic origin should be completely removed, because these tissues impair bone formation and delay bone healing for extended periods. Bleeding must ideally be present to allow for bone growth factors to enter the site. If bleed-ing is inadequate, the cribriform plate should be perforated with either a periodontal curette or a small carbide bur (i.e., #2 round bur) to promote bleeding and potentiate the healing process. Care should be exercised to not fenestrate the buccal or lingual walls and Fig. 34.15 or penetrate any vital structures (e.g., teeth, nerves, sinus, nasal cavity). A serrated curette (i.e., Lucas 86; Salvin Dental) can be used to remove the soft tissue and, secondarily, initiates bleeding. If lateral ridge augmentation is required, then bone decortication holes should be made over the recipient site to initiate angiogenesis and the regional acceleratory phenomenon (RAP) (Figs. 34.13 and 34.14). Socket Grafting of the Extraction SiteSocket-Grafting Technique. Multiple bone graft procedures and studies have been evaluated for socket augmentation at the time of extraction. In most cases clinicians use one technique for socket grafting, without regard to the number of walls of bone remaining. erefore rather than using the same technique regardless of clinical conditions, when bone repair rather than BA• Fig. . Postextraction Debridement. (A) Serrated curette removing debris and soft tissue from within the socket. (B) Round carbide bure debriding the socket. 900PART VII Soft and Hard Tissue Rehabilitationregeneration is likely, the clinician should provide as many keys to bone grafting as possible to increase the socket.What Type of Bone?. Misch and Dietsh16 have suggested dif-ferent graft materials and techniques based on the number of bony walls that remained after the tooth is removed. A thick five bony wall defect will grow bone with almost any resorbable graft material, for example, an alloplast, allograft, or autograft. When a wall of bone is less than 1.5 mm or a labial plate is missing (four bony wall defect), an autograft or freeze-dried bone (FDB) with barrier membrane (BM) and guided bone regeneration increased the predictability of restoring the original bony contour. Becker etal.17 evaluated demineralized freeze-dried bone (DFDB) alone in extraction sockets, and no evidence of bone formation was observed. It appears DFDB alone may be a poor choice for socket grafting. LeKovic etal.18 compared extractions alone with BM with extractions. At 6 months, crestal bone loss (0.38 versus 1.50 mm) and horizontal ridge resorption (−1.31 versus −4.56 mm) were found.18 A two or three bony wall defect usually will require the placement of a regenerative material, and autog-enous bone or possibly a block graft of cortical autogenous bone fixated into the host bone position is suggested for one bony wall defect therefore, debridement should be completd with great care (Figs 34.16).In the literature there exists no consensus with respect to the type of bone and the ideal membrane. Most studies completed on the type of bone include either allografts or xenografts. Allografts include demineralized (DFDBA) or mineralized freeze-dried bone allograft (FDBA). Because of the remaining calcium and phosphate salts, FDBA tends to resorb much slower and therefore maintains space much better than DFDBA. Xenografts resorb very slow, as some studies have shown them to last more than 44 months.19 What Type of Membrane?. e indication for the ideal mem-brane is dictated on the presence of a buccal wall. If all walls of the extraction socket are intact, then a fast-acting collagen is used (e.g., CollaTape, CollaPlug). If the buccal plate is missing, the membrane must be placed olver the buccal wall and should con-sist of a longer-acting material (e.g., longer-acting collagen or polytetrauoroethylene [PTFE]). e advantage of the absorbable membrane (i.e., collagen) is that no reentry is required. e use of a dense PTFE attracts bone cells more readily; however, it is nonresorbable and needs to be removed.ick Five Bony Wall Socket (>1.5 mm). e bone regenera-tion process will restore complete morphology and bone volume to the residual ridge. is most often occurs when there are five thick bony walls around the extraction site (i.e., all remaining walls intact). Most of the keys for predictable bone formation are pres-ent under these conditions, and the socket often forms bone in • Fig. . Care should be exercised when debriding sockets in the mental foramen area because this may cause neurosensory impairment.• Fig. . The proximity of the maxillary posterior teeth to the maxillary sinus may lead to perforation of the sinus and possible infectious episodes.ACBDFive bony wall socketNo Graft or AllograftFour bony wall socketAutograft or RGM andbarrier membraneTwo to three bonywall socketGuided Bone Regeneration+ Autogenous BoneOne bony wall socketOnlay block graft ofautogenous bone• Fig. . The graft materials and techniques for socket grafting are related to the remaining number of bony walls. (A) A thick, five-wall bony socket may remain ungrafted or use of an allograft. A thin wall bony socket used an allograft and collagen membrane. (B) Four-wall socket requires an allograft and a longer-acting membrane. (C, D) A Three-Two- or One wall socket will most likely require autogenous bone, usually in the form of an onlay block. 901CHAPTER 34 Atraumatic Tooth Extraction and Socket Graftingthe extraction socket without loss of width or height. e atrau-matic extraction of a tooth without pathology provides many of the keys necessary for predictable bone regeneration. e extraction process sets up the regional acceleratory phenomenon (RAP) for healing (which increases the rate of repair and adds bone morpho-genetic protein to the site); the five bony walls protect the graft from mobility; the torn blood vessels in the periodontal complex leak growth factors into the region (platelet-derived growth fac-tor, transforming growth factor); the space is maintained by the five walls of the bone; the bony walls provide blood vessels from bone into the site; and the defect size is small (i.e., one tooth). As a result the only key initially missing is soft tissue closure. e soft tissue around the extraction site begins to grow over the clot, and granulation tissue of the socket and within 2 to 3 weeks covers the extraction site (Fig. 34.17). ere exist three treatment options for a few thick ve bony wall socket;Treatment Options (Five-Walled) ->1.5 mm) 1. Immediate Placement Implant. 2. No Treatment (Delayed implant Placement). In most thick bony wall sockets, bone will regenerate without bone graft material added; however, if the buccal plate is less than 1.5 mm, a socket graft is indicated to minimize collapse of the socket and to ensure adequate bone for future implant placement. 3. Socket Grafting: When the extraction socket is grafted, the selec-tion of bone graft material is very important. e graft material selected should coincide with the normal regeneration process. erefore a material that resorbs too fast (e.g., autogenous bone, demineralized bone) or a material that resorbs too slow (e.g., corti-cal mineralized graft, xenograft) is not ideal for use in a ve-walled defect. A much better choice would include a mineralized freeze-dried graft (cortico-cancellous 50-50) or a 70% mineralized/30% demineralized graft material that will maintain the space. Five-Walled Bone-Grafting Technique. After complete socket de-bridement the socket is lled with the bone graft material in small increments. e bone graft material is compressed into the socket to avoid air spaces (i.e., should have “pushback”). Once the socket is completely lled, a collagen plug is hydrated in saline and then cut in half and compressed. e collagen is then inserted over the bone graft. Another option is cutting a piece of collagen tape (i.e., small oval piece) and positioning it over the grafted socket. e collagen is placed over the coronal aspect of the socket and the reected tucked under the minimal ap on the buccal and lingual. e tissue is then closed with a crisscross suture. Ideally the suture technique should include the use of a high-tensile suture material (Fig. 34.18 and Box 34.2) similar to vicryl or PTFE. in Five Bony Wall Socket (< 1.5 mm). For thin ve bony wall sockets, the lack of socket grafting will result in unpredictable healing results. erefore, it is recommended that these types of sockets be treated with a conventional socket grafting technique (# 3 Treatment Option for ick Five Bony Wall Socket).ABDCEF• Fig. . Five-Walled Socket (< 1.5 mm). (A) Atraumatic Extraction. (B) Grafting with allograft. (C) Condensation of the graft. (D) Collagen membrane. (E) Final closure. (F) Six-week healing. 902PART VII Soft and Hard Tissue RehabilitationFour-Wall Bony Socket. Most often in a four-walled defect, the buccal wall is missing. When a labial plate around a socket is miss-ing, the absence of the wall prevents space maintenance, reduces host bone vascularization, and replaces it with soft tissue vascular-ization. e facial bone level will never regenerate above the height of bone on the facial cortical plate of the tooth. Bone augmenta-tion procedures must be used to obtain an ideal volume and con-tour of bone. Sockets with a missing lateral wall are significantly compromised and heal by repair rather than regeneration.When conditions of repair instead of regeneration are present, socket grafting for ridge augmentation at the time of extraction is indicated.20 Tooth extraction without grafting in four-walled defects will result in residual bone loss from resorption. For exam-ple, the maxillary anterior region may be reduced 23% in the first 6 months after an extraction and another 11% over the following 5 years.21 Within 2 years an average of 40% to 60% of the original height and width of bone may be lost with multiple extractions.22e first determination after the tooth extraction is complete is the assessment of the thickness of labial and palatal plates of bone and their relative height to the ideal volume desires. A curette or explorer may be used with the index nger over the buccal plate. If the buccal plate is missing, it will be easy to detect by tactile sensation. When the buccal plate is missing or when it is less than 1.5 mm thick, a socket graft is indicated. e two techniques of choice include a bone graft or a modified socket seal surgery (Figs. 34.19 and 34.26).Four-Walled Bone-Grafting Technique. After complete de-bridement, a collagen membrane is contoured into a modied “V-Shape Cone,” where the narrow part is placed on the inner surface of the buccal wall. Placing the membrane on the external aspect of the remaining buccal wall may compromise the blood supply and healing. e wider part of the membrane is trimmed to cover the socket opening and extend slightly to the lingual to “tuck” under the lingual marginal tissue. After the membrane is in place, the socket is lled with the bone graft material in small increments. e material is compressed into the socket to avoid air spaces (i.e., should have “pushback”). e suture technique should include the use of a high-tensile suture material. A crisscross suture is recom-mended, which encompasses the membrane and graft material. is will prevent the loss of the membrane and will contain the graft material. In some cases the membrane may be sutured to the tissue (Fig. 34.20 and Box 34.3).NOTE: e membrane should cover only the missing buccal wall; the other walls should not have membrane coverage as this will decrease the healing of the area. e goal of the membrane is to prevent the soft tissue from repopulating the defect. If a mem-brane is not used, there is a greater chance of the graft particles migrating, resulting in unpredictable results. One, two, and three bony wall sockets. When multiple walls of bone are missing, the greater the need for autogenous bone. A particulate graft is unpredictable in these situations. erefore a donor site is most often used to obtain the autogenous bone: mandible (i.e., ramus, symphysis) or maxilla (i.e., tuberosity). In some cases (i.e. three bony wall sockets) a membrane tent screw may be used for space maintenance (Fig. 34.21) via guided bone regeneration protocols (GBR). Obtaining Autogenous Grafting: Secondary SitesMandibular Ramus Donor Site: “Scraping Technique”When autogenous bone is indicated, there exists many possible locations to harvest. One option which is easy, simple, and mini-mal morbidity is to obtain autogenous bone is to expose the man-dibular ramus and remove bone from the external oblique ridge with double-action rongeurs. e “scrapings” may be placed in a surgical bowl with sterile saline. A second option to obtain smaller autogenous chips is to remove a block graft from the lateral ramus. Ramus block grafts may be taken; however, the blocks need to be reduced into smaller pieces, which is rather time consuming. In addition, a ramus block graft (i.e., veneer graft of the lateral ramus) has a greater morbidity rate and far greater postoperative complications (Fig. 34.22). Three Treatment Options: 1. Immediate Implant Placement 2. No Socket Graft (delayed implant placement) 3. Socket GraftReflection: conservativeAllograft: cortico-cancellous mineralized allograft or 70% mineralized/30%demineralized allograftMembrane: regular collagen (∼collagen plug)Closure: primary closure is unachievableSuture: crisscross suture (polytetrafluoroethylene or Vicryl)Immediate implant: fair to good candidateProsthesis: Usually an FP-1 fixed prosthesis*Thin Five-Walled Socket is treated with option # 3. • BOX 34.2 Five-Walled Socket (> 1.5 mm)AB• Fig. . Five Wall Socket: (A, B) All five walls remaining. 903CHAPTER 34 Atraumatic Tooth Extraction and Socket GraftingMandibular Ramus Donor Site: “Trephine Bur Bone Harvest”A more aggressive technique to obtain autogenous bone cores from the ramus with trephine burs. Trephine burs are end-cutting burs that are available in various diameters with the 6- to 8-mm trephine being the most popular to harvest bone from the ramus. For this technique, the ramus has become a more popular site in comparison with the symphysis area because of less morbidity. Once the ramus site (i.e., external oblique) is reected, the tre-phine bur is used to harvest the autograft. Half of the trephine bur A B• Fig. . Four Wall Socket: (A, B) Buccal wall missing.ABDC• Fig. . Four-Walled Socket. (A) Postextraction. (B) Extended collagen membrane. (C) Membrane in place. (D) Postsuturing. 904PART VII Soft and Hard Tissue RehabilitationABC• Fig. . Mandibular Ramus Scraping Technique. (A) Ramus exposed. (B) Double-action rongeur. (C) Autograft stored in sterile saline.is placed over the external oblique bony ridge, whereas the other half is lateral to the bone and above the reected masseter muscle, which is elevated o the anterior lateral aspect of the ramus. Strict reection of the soft tissues is warranted. e trephine bur is used with latch type angled surgical drill at 2000-2500 rpm with copi-ous saline irrigation, 5 to 8 mm deep, making sure it is above and lateral to the position of the inferior alveolar nerve, artery, and vein. e inferior alveolar canal position may be identied via a cone beam computed tomography (CBCT) examination survey.After the rst trephine osteotomy is completed, the second site is completed above the half circle created by the first osteotomy and overlays the circle in the top third, or 3 mm from the top. is is repeated in the bottom third of the initial half circle, 3 mm above the bottom. ree interlacing semicircles are created along AB• Fig. . (A) 3 - Wall socket - missing lingual and mesial walls, (B) 1 - Wall socket - missing all walls except the apical wall.Reflection: conservativeAllograft: cortico-cancellous mineralized allograft or 70% mineralized/30% demineralized allograftMembrane: extended collagen or cytoplast (PTFE), (acellular dermis—thin biotype)Closure: primary closure is usually unachievableSuture: crisscross Suture (PTFE or Vicryl)Immediate implant: poor to fair candidateProsthesis: Most likely a FP-2 or FP-3 prosthesis*Autogenous bone can be used with allograft bone to accelerate healing and increase predictability. • BOX 34.3 Four-Walled Bony Socket 905CHAPTER 34 Atraumatic Tooth Extraction and Socket Graftingthe external oblique of the ascending ramus. A large No. 8 round carbide in a straight handpiece then may score the lateral aspect of the ramus, corresponding to the depth of the trephine bur semicircle cuts. A chisel or surgical curette then may greenstick fracture the donor bone pieces from the ramus. ese harvested pieces are usually an ideal size to use in the graft site, because they are approximately 5 × 3 × 5 mm large. A collagen sponge (e.g., OraTape, OraPlug) may be placed in the donor site and the tis-sues approximated for primary closure. One disadvantage of the trephine ramus technique is the loss of bone from the multiple osteotomies of the burs (Fig. 34.23). Maxillary Tuberosity Donor Sitee tuberosity oers a variable amount of trabecular bone, which is dependent on the amount of maxillary bone atrophy and maxil-lary sinus pneumatization. is area is convenient and often the rst choice of autogenous donor sites for maxillary sinus graft-ing23,24; it also may be considered for smaller areas of ridge aug-mentation25,26 (Fig. 34.24). e cancellous nature of the bone allows it to be molded into an alveolar defect, such as an extraction socket.17 e trabecular graft will more often require the use of a barrier membrane to minimize resorption and stabilize the graft.27 e tuberosity autograft has growth factors for osteoinduction and to accelerate blood vessel growth in the host site.e thicker soft tissue in the tuberosity region can mislead the assessment of this donor site. e tuberosity should be evaluated with a CBCT survey to determine the maxillary sinus location and the amount of host bone present. e anatomic limitations of this area include the maxillary sinus, pterygoid plates, adjacent teeth when present, and the greater palatine canal. e tuberosity technique includes making a vertical incision a posteriorly at the lateral aspect of the maxilla and is extended ante-riorly across the tuberosity into the molar region. After reection of a mucoperiosteal ap, bone may be harvested from the tuberos-ity with a rongeur or chisel. Removing the graft with a chisel will allow the harvesting of a larger piece of bone. However, the sinus may inadvertently be entered during removal of the graft, with resultant oroantral communication. If this is observed at suture removal, the patient is instructed to avoid creating high nasal ABCD• Fig. . Ramus Trephine Harvest - (A) 6 mm Trephine bur in latch handpiece, (B, C) Osteotomy per-formed over external oblique ridge, (D) Autogenous bone fragments.• Fig. . The maxillary tuberosity region is a common bone donor site for bone grafting when trabecular bone is the desired product. Trabecular bone has growth factors for blood vessels and for regeneration of a bone defect. 906PART VII Soft and Hard Tissue Rehabilitationpressures and should be placed on antibiotics to prevent infection and ensure normal drainage. Most often, the oroantral opening will close on its own (Fig. 34.25). If the oral-antral opening does not close, surgical closure is usually indicated. Socket Seal SurgeryA composite graft socket seal surgery was developed by Misch et al.28,29 composed of connective tissue, periosteum, and trabecular bone used to seal a fresh extraction socket. A con-nective tissue graft has the advantage over a keratinized graft by blending into the surrounding attached gingival regions, oering similar color and texture of the epithelium. is is most advantageous in the maxillary anterior region and other esthetic areas. e composite graft also contains autogenous bone. e major advantage of autologous bone is a more rapid and predictable bone formation via osteogenesis. e main dis-advantage is the tuberosity bone resorbs rather fast, therefore unpredictable bone growth in quantity may result.First, a CBCT evaluation should be completed to determine if adequate bone is present in the tuberosity location. A 6- to 10-mm trephine bur corresponding to the extraction site diam-eter is used in a slow-speed, high-torque handpiece (e.g., 16:1 or 20:1) to harvest a gingival graft with underlying bone. e most common site for the intraoral composite graft harvest is the max-illary tuberosity region (see Fig. 34.10). e trephine bur will drill through the unreected, keratinized, attached gingiva and into the bone of the tuberosity region at the prescribed depth related to the thickness of the tissue and the amount of donor bone available. Care should be exerted not to enter the antrum. A trephine bur may be used as a lever to greenstick fracture the bone core from its base, once it is in position within the bone. A Molt elevator may also be used for this purpose. e bone core (usually 5–10 mm in height) and the attached soft tissue (about 3 mm in height) is trimmed of its epithelium with tissue scissors, leaving 3 to 6 mm of connective tissue attached to the bone core. If the bone core does not fill the extraction socket completely, a mineralized bone graft material (e.g., cortico-cancellous FDBA) may be used in the apical portion of the socket, provided the labial plate is still intact. Because the new bone forms from the apical portion of the socket, this is the least important region to augment.If no bone plate remains in the apical half of the socket, addi-tional autogenous bone should be harvested from an additional intraoral site to overfill the apical half of the socket. e bone of the composite graft (connective tissue attached to periosteum and bone) is compressed and fitted into the remaining portion of the socket.e tissue of the composite graft will seal the socket and remain above the surrounding gingiva. A mallet and blunt instrument should be used to lightly tap it into place and compress the bony core to conform to the crestal contour of the socket. e connec-tive tissue portion of the graft is then sutured to the surrounding gingival tissue with facial and palatal interrupted 4–0 PTFE or Vicryl sutures (Fig. 34.26). A removable transitional prosthesis should not be permitted to load the tissue during the first 6-8 weeks after extraction; otherwise the composite graft may become mobile and sequestrate.e benefits of the composite graft socket seal surgery tech-nique permit the surrounding keratinized gingival tissues to migrate and form a similar color and texture of keratinized tis-sue over the socket. e blood supply to the composite graft is established from the surrounding soft tissue. In addition, because autogenous bone is used as the graft in the coronal half of the socket, where the facial bone is most often very thin or absent, more predictable results will occur than if an allograft were used. e transfer of the bone graft with an intact periosteal layer expe-dites revascularization and may decrease the healing time.30,31 As a result, reentry may be in 4 to 5 months, and placement of an ideal implant diameter is often made possible.Use of Bone Growth Factors in Extraction SiteBlood ConcentratesAn option for faster healing and possibly better bone regenera-tion is the use of blood concentrates alone or in combination with bone graft material. Many authors have discussed the use of blood concentrates in the post-extraction site. Choukroun et al. described the use of his second generation platelet concentrate platelet rich fribrin (PRF) with socket grafting.32 PRF is a natu-ral brin biomaterial that allows for greater microvascularization and cell migration into the wound. Growth factors have been shown to be released up to 28 days after placement in extrac-tion sites.33 Histologically, the brin clot stimulates the extrac-tion socket environment for more ideal bone regeneration and remodeling.34,35 Rao et al. reported better bone regeneration and increased bone density in extraction sites with PRF alone compared to a control group.36 However, the authors advocate if PRF is to be used, it is combined with bone graft material, which has been shown in the literature to facilitate more ideal and faster bone regeneration.37Bone Morphogenic Proteine use of bone morphogenic protein (BMP) has been investi-gated with the treatment of post-extraction sockets. BMP’s are members of a family of proteins that are highly osseoinductive and stimulate mesenchymal cells to enhance bone growth. Fiorel-lini et al.38 conducted controlled studies with the use of rhBMP-2 (bone morphogenic protein) with acellular collagen sponge in extraction sites. ey concluded the use of BMP induced signi-cant bone formation for the future placement of dental implants. Histologically, the bone was similar to native bone and was load bearing. Rh-BMP is commercially availability as an osteoinduc-tive alloplastic bone graft material (Infuse Bone Graft, Medtronic Spinal and Biologics, Memphis, TN, USA).• Fig. . Tuberosity Harvest with Double Action Rongeurs. 907CHAPTER 34 Atraumatic Tooth Extraction and Socket GraftingProvisional RestorationsIn most cases of socket-grafting site preservation, the patient will require a provisional restoration to maintain esthetics and function, and to protect the surgery site. For an interim removable prosthesis the implant clinician should ensure the prosthesis is tooth supported (i.e., has vertical stops on the adjacent teeth to prevent the partial denture tooth from exert-ing pressure directly on the tissues around the extractions site), and the surface area over the surgical site should be hygienic in contour. If a fixed prosthesis is used (e.g., resin bonded bridge), the undersurface should not impinge on the tissue (Fig. 34.27). ABCDEF• Fig. . (A) The left maxillary central incisor has an absence of facial cortical plate (a four bony wall defect). (B) A trephine bur diameter is selected that corresponds to the size of the extraction site (Bioho-rizons, Birmingham, Ala.). (C) The trephine bur performs an osteotomy directly through the keratinized attached gingiva and into the tuberosity, and proceeds to the floor of the antrum. (D) The keratinized tis-sue, mucosa, periosteum, and bone of the composite graft are removed from the trephine bur. The tissue thickness is reduced to 2 to 3 mm above the bone. The surface of the tissue is connective tissue. (E) The composite graft is inserted into the extraction socket, and a blunt instrument (e.g., mirror handle) and mallet taps the composite graft into the socket so that the connective tissue is level with the surrounding tissues. (F) Sutures are positioned to maintain the composite graft in place. 908PART VII Soft and Hard Tissue RehabilitationABC• Fig. . Provisional Restoration. (A) Postextraction. (B) Overlay temporary bridge (i.e., Snap-On Smile). (C) Interim prosthesis inserted placing no pressure on extraction site.Socket Graft Healingere exist many variables when determining when a socket graft site is healed for implant placement. Care should be exercised to place the implant only after adequate hard and soft tissue healing is obtained. Healing of the hard and soft tissues is determined by the size of the defect, type of graft material, type of bone graft, use of a membrane, and blood supply to the area. Usually a healing time ranging from 4 - 8 months is required. Radiographically, usu-ally when the cribriform plate is not seen on the x-ray, adequate healing is achieved (Fig. 34.28). Socket Grafting ContraindicationsInfected SiteA relative contraindication to the socket-grafting protocol is the presence of an acute infection. A tooth demonstrating active infec-tion (i.e., exudate or stula) should be extracted without place-ment of bone graft material. e patient’s acute infection should be managed by drainage of the infection, lavage of the infected area, and the use of systemic antibiotics. e bone grafting may be delayed for a minimum of 8 weeks postextraction to decrease the possibility of a graft infection. In addition, this delay will ensure better tissue quality (i.e., primary closure of the grafted site with keratinized tissue), elevated osteoblast activity, and a newly formed woven bone within the socket. e disadvantage of this surgical approach is the need for an additional surgery and a extended total treatment time (Fig. 34.29). Proximity to Vital Structure (Mental Foramen, Mandibular Canal)In the mandibular premolar area, 25% to 38% of the time the mental foramen is superior to the apex of either of the premolars. e location of the mental foramen is highly variable; however, it is most commonly located in the rst or second premolar area. If a premolar is extracted, CBCT measurements need to conrm adequate bone below the apex. e clinician must be careful in debriding this area because nerve impairment may occur.• Fig. . Healed graft site exhibiting lack of cribriform plate present. 909CHAPTER 34 Atraumatic Tooth Extraction and Socket GraftingIn the mandibular molar area, especially in type 1 nerve loca-tions (i.e., mandibular canal close to mandibular teeth apexes), after extraction it is important not to curette or place graft mate-rial in close proximity to the nerve canal (Fig. 34.30). In many cases, no superior cortical bone is present over the mandibluar canal. Maxillary SinusIn the maxillary rst molar area, approximately 42% of the max-illary roots are located in the sinus proper.39 When the tooth is extracted the sinus membrane may be perforated, and an exposure may occur. If grafting is completed, bone graft material may be introduced into the sinus proper, leading to the possibility of acute rhinosinusitis or oral-antral stula formation (Fig. 34.31). Socket Graft ComplicationsInadequate FillCare should be exercised in lling the entire socket from the apex to the ridge with no voids. is is most often to occur in multirooted teeth, especially when root diameter is small. Small increments of graft material should be introduced into the socket at a time to avoid inad-equate lls. Complications occur when too large of a syringe or too much volume of material is introduced into the socket and it becomes dicult to condense properly. Amalgam carriers with small amalgam pluggers can be used to graft smaller sized sockets (Fig. 34.32). Too Dense of Socket FillAvoid excessive pressure when condensing the graft material into the socket. Too dense of a particulate graft ll may compromise the vascularity within the socket and nal healing (Fig. 34.33). Usually when “push-back” of the material occurs, the socket is grafted suciently. Overfilling the Extraction SocketExcess graft material in height placed in the socket may compromise the soft tissue healing over the extraction socket. e graft material should be placed into the socket to the level of the surrounding socket walls. When excess bone is placed into an extraction site, it will usually be slowly lost postoperatively (Fig. 34.34). In addition, soft tissue healing over the extraction site will be delayed. Leaving Soft Tissue or Root FragmentAfter extraction the tooth and root structure should always be evaluated to verify no tissue or root tip is inadvertently left in the socket. Grafting over soft tissue or a root tip will increase the possibility of infection, decrease the amount of bone formation, and delay the healing process (Fig. 34.35). Use of Incorrect Bone Graft MaterialCertain bone substitutes are not ideal for socket grafting. Some of these materials include nonresorbable hydroxyapa-tite, calcified copolymer alloplast (Bioplant HTR; Bioplant • Fig. . Tooth With Apical Infection. Care should be exercised in grafting into an infected socket.BA• Fig. . Neurosensory Impairment (A and B) Socket graft material in close approximation to the man-dibular canal. Care should be exercised in type 1 nerve paths. AB• Fig. . (A and B) Inadequate socket fill (arrows). Graft material should be placed into the extraction sockets in small increments so that voids and inadequate fill do not occur.A B• Fig. . (A) Fill should be completed in small increments to allow for an ideal fill. (B) Adequate density is achieved when “pushback” occurs when packing the graft material.• Fig. . Maxillary Sinus Approximation. Approximately 42% of molar roots are into the sinus floor, leading to possible perforation and extrusion of graft material into the sinus. Note the lingual root perforation into the maxillary sinus. 911CHAPTER 34 Atraumatic Tooth Extraction and Socket GraftingInc.), and “bioactive” glasses. Most of the alloplasts either do not resorb or resorb slowly with a fibrous encapsulation, thereby making them nonideal for subsequent implant place-ment (Box 34.4). Ideally, the bone graft material should resorb at the same rate that bone formation occurs (i.e. mineralized cortico-cancellous allograft or 70% mineralized/30% demin-eralized allograft).Conclusione extraction of a natural tooth is one of the most widely per-formed procedures completed in dentistry today. After tooth extraction, it is well documented in the literature signicant morphologic and dimensional changes occur to the extraction socket. When hard and soft tissue is lost, an increased diculty in implant placement results, which compromises the nal pros-thetic outcome. erefore, it is imperative that extraction sites are treatment predictably to maintain the hard and soft tissue volume. Many clinicians treat all sockets the same, with a set treatment protocol to provide for placement of a future implant. However, the morphology, most specically the number of remaining bony walls, play a signicant role in the amount of resorption after extraction. erefore, an extraction socket treatment protocol has been established which is dictated on the number of remaining walls. Each classication involves a dierent treatment protocol with the goal of maintaining the available bone and regenerating bone within the socket area so that ideal implant placement may be completed at a later date. In addition, the clinician must have a strong understanding of the indications and contraindications of socket grafting along with the ideal treatment of associated complications.References 1. Irinakis, T., & Tabesh, M. (2007). Preserving the socket dimensions with bone grafting in single sites: an esthetic surgical approach when planning delayed implant placement. J Oral Implantol. 33(3), 156-163. 2. Ohta Y. Comparative changes in microvasculature and bone during healing of implant and extraction sites. J Oral Implant. 1993;3:184– 198. 3. Lin WL, McCulloch CA, Cho MI. Dierentiation of periodon-tal ligament broblasts into osteoblasts during socket healing after tooth extraction in the rat. Anat Rec. 1994;240:492–506.• Fig. . Overlling the Extraction Socket. Bone should not be grafted above the cortical plate levels. This will result in poor wound healing migration of the graft material and incision line opening.• Fig. . Retained Root Tip. After the extraction, radiographic evi-dence should verify no retained roots in the socket. 1. Immediate implant placement (Usually for 5-walled sockets) 2. No Socket Graft - Delayed Implant Placement a. Five-walled socket (> 1.5 mm of buccal plate) b. Infected site 3. Socket graft—five-walled socket (< 1.5 mm of buccal plate) • Allograft + CollaTape/CollaPlug 4. Socket graft—four-walled socket • Allograft + extended collagen/dense polytetrafluoroethylene membrane 5. Socket graft—one-, two-, three-walled socket • Autograft + allograft • BOX 34.4 Summary of Post-Extraction Options 912PART VII Soft and Hard Tissue Rehabilitation 4. Araujo MG, Berglundh T, Lindhe J. On the dynamics of periodon-tal tissue formation in degree III furcation defects. An experimental study in dogs. J Clin Periodontol. 1997;24:738–746. 5. Cardaropoli G, Araujo M, Lindhe J. Dynamics of bone tissue forma-tion in tooth extraction sites. An experimental study in dogs. J Clin Periodontol. 2003;30:809–818. 6. 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