Basic knowledge 










9
Chapter2
Basic knowledge
Anatomy of the teeth 10
Dental occlusion 14
Anatomy of the oral cavity 18
Anatomy of the facial skeleton 22
Anatomy of the oral and facial muscles, nerves, and glands 28
Anatomy of the neck 32
Medical ‘clerking’:history and full body examination 36
Examination of the oral cavity 40
Examination of the face and neck 42

10
CHAPTER2 Basic knowledge
10
Anatomy oftheteeth
Anatomy ofatooth
A tooth is made up of a crown, a neck, and root(s). Each tooth has an indi-
vidual nerve supply, arterial supply, and venous drainage, all of which make
up the pulp of the tooth which lies within the root canals and central pulpal
cavity. Surrounding the pulp is organic dentine, which is tubular and porous
in its structure. The crown of the tooth has an outer coating of enamel,
which is 2mm thick. This is a very hard inorganic layer with the purpose
of biting through or chewing food. The roots have a thinner coating of
cementum, and are ‘suspended’ in the supporting alveolar bone by the peri-
odontal ligament (PDL). The PDL has its own blood supply, and provides
the proprioceptive sensory feedback to the brain, localizing the position of
each individual tooth when the supporting jaw bites on something or if the
tooth is percussed (see Fig.2.1).
Tooth terminology
Mesialcloser to midline.
Distalfurther from midline.
Buccalfacing the cheeks.
Labial— facing thelips.
Palatalfacing the palate (upper teethonly).
Lingualfacing the tongue (lower teethonly).
Occlusalthe biting surface of a premolar/ molartooth.
Acute insults
Enamel
Dentine
Gum
Pulp
Cementum
Periodontal membrane
Compact bone (lamina dura
)
Spongy bone
Gingival crevasse
Chronic symptoms
Fig.2.1 Dental anatomy.

ANATOMY OFTHETEETH
11
Incisalthe biting edge of an incisor or caninetooth.
Coronal— closer to the crown in longaxis.
Apical— closer to the root in longaxis.
Chartingteeth
When documenting or charting teeth, the Zsigmondy– Palmer system is
commonly used which places the teeth in a grid (as seen from the front of
the mouth):
Deciduous teeth:
E D C B A A B C D E
E D C B A A B C D E
Permanent teeth:
8 7 6 5 4 3 2 1 1 2 3 4 5 6 7 8
8 7 6 5 4 3 2 1 1 2 3 4 5 6 7 8
Eruptiondates
For a summary of eruption dates for deciduous and permanent teeth, see
Tables 2.1 and2.2.
Table2.1 Eruption dates— deciduous teeth (primaryteeth)
Age (months) 8– 12 9– 13 16– 22 13– 19 25– 33
Upper A B C D E
Lower A B C D E
Age (months) 6– 10 10– 16 17– 23 14– 18 23– 31
Table2.2 Eruption dates— permanent teeth (secondaryteeth)
Age
(years)
7– 8 8– 9 11– 12 10– 11 10– 12 6– 7 12– 13 17– 21
Upper 1 2 3 4 5 6 7 8
Lower 1 2 3 4 5 6 7 8
Age
(years)
6– 7 7– 8 9– 10 10– 12 11– 12 6– 7 12– 13 17– 21

12
CHAPTER2 Basic knowledge
12
Tooth morphology
Dental undergraduates spend a long time learning the various tooth and
root shapes, as each tooth is dierent and there may be variations. In
OMFS, it is important to appreciate the general rules ofthumb:
Upper teethroots
1s, 2s, and 3s have conicalroots.
4s and 5s have either two ne roots or a attenedroot.
6s, 7s and 8s have three roots. The palatal root is often longer than the
two (mesial and distal) buccal roots. The roots can be fusedin8s.
Lower teethroots
1s, 2s, and 3s often have attened or oval- shapedroots.
4s and 5s have mostly single conical roots, but occasionally have
tworoots.
6s, 7s, and 8s have two roots (mesial and distal). The roots can
fusedin8s.
0 Non- dentally qualied OMFS doctors may have to re- implant a tooth
in A&E as part of emergency treatment (see E ‘Re- implanting and splint-
ing teeth’, p. 231). If so, make sure it is the right way round! The best way
to be certain of this is to look at the crown. Anterior teeth have at labial
surfaces facing the lips, and concave palatal/ lingual surfaces facing the palate
or tongue. Posterior teeth generally have taller, atter buccal surfaces facing
the cheeks, and lower, more bulbous surfaces facing the tongue or palate.

ANATOMY OFTHETEETH
13

14
CHAPTER2 Basic knowledge
14
Dental occlusion
Much of OMFS work involves maintaining/ restoring/ improving the
dental occlusion, in particular cancer resection and reconstruction, facial
hard tissue trauma, and deformity surgery.
Aworking understanding of the occlusion through dental training
is often what dierentiates OMFS surgeons from any other type of
surgeon.
Terminology
Occlusion:in simple terms, means the contact betweenteeth.
Malocclusion:a misalignment of the teeth and jaws— a ‘badbite’.
Centric occlusion:the occlusion made when the teeth meet together in
‘maximum interdigitation’. Ask the patient to bite down on their back
teeth and view from each side with a pentorch.
Ideal occlusion:anatomically perfect ClassIocclusion— see later in
thistopic.
Lateral excursions:lateral movements of the mandible to eachside.
Anterior open bite:a space exists between the upper and lower incisors
when viewed from the front, with the posterior teeth otherwise in
occlusion.
Lateral open bite:a space existing on one side of the occlusion.
Crossbite:teeth are displaced either buccally or lingually. Can be
anterior/ posterior and unilateral/ bilateral.
Overbite:the extent of overlap of the upper central incisors over the
lower central incisors when viewed from thefront.
Overjet:the extent of the protrusion of the upper teeth ahead of the
lower teeth when viewed from the side. Can be termed a ‘reverse
overjet’ if the lower teeth are protruding ahead of the upperteeth.
Prognathic:abnormal protrusion of upper/ lower jaw,
overdevelopedjaw.
Retrognathic:abnormal retrusion of upper/ lower jaw,
underdevelopedjaw.
Classications ofocclusion
British Standards Institute (BSI) classication
See Fig. 2.2. Based on the incisor relationship:
ClassI:the incisal edge of the lower incisor contacts or lies below
the cingulum of the upper central incisor (Fig. 2.2a). Acingulum is a
convexity found on the lingual surface of anteriorteeth.
ClassII:the incisal edge of the lower incisor lies posterior to the
cingulum of the upper incisor. There are twotypes:
Division I:the upper incisors are proclined or of an average inclina-
tion and there is an increased overjet (Fig.2.2b).
Division II:the upper central incisors are retroclined (Fig.2.2c).
ClassIII:the incisal edges of the lower incisor lie anterior to the cingulum
plateau of the upper incisors (Fig.2.2d).

DENTAL OCCLUSION
15
Factors causing malocclusion
Skeletal factors
The anteroposterior relationship between the upper and lower jaw has an
inuence on the dental arches. This is best gauged through cephalomet-
ric analysis of a lateral cephalogram (See E ‘Facial and skull radiography’,
pp.56–9), which is outside the scope of this handbook, but can be sum-
marized as follows:
Skeletal Ibase:the jaws are in their ideal anteroposterior relationship in
occlusion.
Skeletal II base:the lower jaw in occlusion is positioned more
posteriorly.
Skeletal III base:the lower jaw in occlusion is positioned more anteriorly.
(a)(b)
(c)
(d)
Fig.2.2 BSI classication of occlusion. Reproduced from Mitchell L, MitchellD,
Oxford Handbook of Clinical Dentistry (5th edn), p.125 (Oxford:2009). With
permission from Oxford UniversityPress.

16
CHAPTER2 Basic knowledge
16
Genetic factors
Skeletal factors.
Tooth size and number.
Metabolic factors
For example, a pituitary adenoma secreting growth hormone can result in
mandibular prognathism and progressive malocclusion usually presenting in
middle to lateage.
Environmental factors
Soft tissue factors:lips, cheeks, and tongue can either move or stabilize
teeth overtime.
Habits:thumb/ nger sucking, pen biting,etc.
Trauma:fractured mandible or midface, traumatized dentition.
Temporomandibular joint (TMJ) dislocation.
Local factors
Variation in number ofteeth.
Spacedteeth.
Problems caused bymalocclusion
Teeth
Teeth can break, become mobile, or wear; crowns or llings can be dis-
placed, causing symptoms.
Softtissue
Gums can recede, causing sensitivity.
Temporomandibularjoint
Patients can develop symptoms such as clicking, grinding, locking, pain,
trismus, headache, tinnitus, muscle fatigue and spasms, sinus/ eye pain, and
neck/ backpain.
Functional
Diculty biting or chewing.
Patient aesthetic concerns
Altered appearance from the perceived ‘norm’.
Psychosocial problems
Low condence, low mood. May be subject to bullying or harassment.

DENTAL OCCLUSION
17

18
CHAPTER2 Basic knowledge
18
Anatomy ofthe oralcavity
For an overview of mouth and throat structures, see Fig. 2.3. Dental
graduates will have an advantage here, as many medical anatomy
courses will not have covered this in detail.
The oral cavity is split anatomically into twoparts:
The vestibule is the space between the lip/ cheeks and the teeth/
gingivae.
The mouth proper is the space within the dental arches.
The oral cavity includes the lips, the buccal mucosae, the teeth, the
gingivae, anterior 2/ 3 of tongue, the oor of mouth, the retromolar
trigone, and the hard palate.
Posteriorly, the oral cavity communicates with the oropharynx, which
encompasses the posterior 1/ 3 of tongue, soft palate, the palatine
tonsils, and the upper pharynx.
Gingivae
The gums provide a soft tissue seal around the teeth. They consist of thicker
attached keratinized gingivae, which include the embrasure spaces between
the teeth as interdental papillae. The attached gingivae become non-
attached (and non- keratinized) at the mucogingival junction, often clearly
seen as a darker redline.
Epiglottis
Vallecula
Base of tongue
(posterior third)
Sulcus terminalis
Body of tongue
(anterior two-thirds)
Median lingual sulcus
Palatine tonsil
Lingual tonsil
Foramen caecum
Circumvallate papillae
Fungiform/
liform papillae
Fig.2.3 Gross anatomy of the dorsum of the tongue. Reproduced from Sengupta
Aand Giles A, ‘Oral Complications of Cancer and its Management’ (2010) with
permission from Oxford UniversityPress.

You're Reading a Preview

Become a DentistryKey membership for Full access and enjoy Unlimited articles

Become membership

If you are a member. Log in here

Was this article helpful?

9 Chapter2Basic knowledgeAnatomy of the teeth 10Dental occlusion 14Anatomy of the oral cavity 18Anatomy of the facial skeleton 22Anatomy of the oral and facial muscles, nerves, and glands 28Anatomy of the neck 32Medical ‘clerking’:history and full body examination 36Examination of the oral cavity 40Examination of the face and neck 42 10CHAPTER2 Basic knowledge10Anatomy oftheteethAnatomy ofatoothA tooth is made up of a crown, a neck, and root(s). Each tooth has an indi-vidual nerve supply, arterial supply, and venous drainage, all of which make up the pulp of the tooth which lies within the root canals and central pulpal cavity. Surrounding the pulp is organic dentine, which is tubular and porous in its structure. The crown of the tooth has an outer coating of enamel, which is 2mm thick. This is a very hard inorganic layer with the purpose of biting through or chewing food. The roots have a thinner coating of cementum, and are ‘suspended’ in the supporting alveolar bone by the peri-odontal ligament (PDL). The PDL has its own blood supply, and provides the proprioceptive sensory feedback to the brain, localizing the position of each individual tooth when the supporting jaw bites on something or if the tooth is percussed (see Fig.2.1).Tooth terminology• Mesial— closer to midline.• Distal— further from midline.• Buccal— facing the cheeks.• Labial— facing thelips.• Palatal— facing the palate (upper teethonly).• Lingual— facing the tongue (lower teethonly).• Occlusal— the biting surface of a premolar/ molartooth.Acute insultsEnamelDentineGumPulpCementumPeriodontal membraneCompact bone (lamina dura)Spongy boneGingival crevasseChronic symptomsFig.2.1 Dental anatomy. ANATOMY OFTHETEETH11 • Incisal— the biting edge of an incisor or caninetooth.• Coronal— closer to the crown in longaxis.• Apical— closer to the root in longaxis.ChartingteethWhen documenting or charting teeth, the Zsigmondy– Palmer system is commonly used which places the teeth in a grid (as seen from the front of the mouth):• Deciduous teeth:E D C B A A B C D EE D C B A A B C D E• Permanent teeth:8 7 6 5 4 3 2 1 1 2 3 4 5 6 7 88 7 6 5 4 3 2 1 1 2 3 4 5 6 7 8EruptiondatesFor a summary of eruption dates for deciduous and permanent teeth, see Tables 2.1 and2.2.Table2.1 Eruption dates— deciduous teeth (primaryteeth)Age (months) 8– 12 9– 13 16– 22 13– 19 25– 33Upper A B C D ELower A B C D EAge (months) 6– 10 10– 16 17– 23 14– 18 23– 31Table2.2 Eruption dates— permanent teeth (secondaryteeth)Age (years)7– 8 8– 9 11– 12 10– 11 10– 12 6– 7 12– 13 17– 21 Upper 1 2 3 4 5 6 7 8Lower 1 2 3 4 5 6 7 8Age (years)6– 7 7– 8 9– 10 10– 12 11– 12 6– 7 12– 13 17– 21 12CHAPTER2 Basic knowledge12Tooth morphologyDental undergraduates spend a long time learning the various tooth and root shapes, as each tooth is dierent and there may be variations. In OMFS, it is important to appreciate the general rules ofthumb:Upper teethroots• 1s, 2s, and 3s have conicalroots.• 4s and 5s have either two ne roots or a attenedroot.• 6s, 7s and 8s have three roots. The palatal root is often longer than the two (mesial and distal) buccal roots. The roots can be fusedin8s.Lower teethroots• 1s, 2s, and 3s often have attened or oval- shapedroots.• 4s and 5s have mostly single conical roots, but occasionally have tworoots.• 6s, 7s, and 8s have two roots (mesial and distal). The roots can fusedin8s.0 Non- dentally qualied OMFS doctors may have to re- implant a tooth in A&E as part of emergency treatment (see E ‘Re- implanting and splint-ing teeth’, p. 231). If so, make sure it is the right way round! The best way to be certain of this is to look at the crown. Anterior teeth have at labial surfaces facing the lips, and concave palatal/ lingual surfaces facing the palate or tongue. Posterior teeth generally have taller, atter buccal surfaces facing the cheeks, and lower, more bulbous surfaces facing the tongue or palate. ANATOMY OFTHETEETH13 14CHAPTER2 Basic knowledge14Dental occlusion• Much of OMFS work involves maintaining/ restoring/ improving the dental occlusion, in particular cancer resection and reconstruction, facial hard tissue trauma, and deformity surgery.• Aworking understanding of the occlusion through dental training is often what dierentiates OMFS surgeons from any other type of surgeon.Terminology• Occlusion:in simple terms, means the contact betweenteeth.• Malocclusion:a misalignment of the teeth and jaws— a ‘badbite’.• Centric occlusion:the occlusion made when the teeth meet together in ‘maximum interdigitation’. Ask the patient to bite down on their back teeth and view from each side with a pentorch.• Ideal occlusion:anatomically perfect ClassIocclusion— see later in thistopic.• Lateral excursions:lateral movements of the mandible to eachside.• Anterior open bite:a space exists between the upper and lower incisors when viewed from the front, with the posterior teeth otherwise in occlusion.• Lateral open bite:a space existing on one side of the occlusion.• Crossbite:teeth are displaced either buccally or lingually. Can be anterior/ posterior and unilateral/ bilateral.• Overbite:the extent of overlap of the upper central incisors over the lower central incisors when viewed from thefront.• Overjet:the extent of the protrusion of the upper teeth ahead of the lower teeth when viewed from the side. Can be termed a ‘reverse overjet’ if the lower teeth are protruding ahead of the upperteeth.• Prognathic:abnormal protrusion of upper/ lower jaw, overdevelopedjaw.• Retrognathic:abnormal retrusion of upper/ lower jaw, underdevelopedjaw.Classications ofocclusionBritish Standards Institute (BSI) classicationSee Fig. 2.2. Based on the incisor relationship:• ClassI:the incisal edge of the lower incisor contacts or lies below the cingulum of the upper central incisor (Fig. 2.2a). Acingulum is a convexity found on the lingual surface of anteriorteeth.• ClassII:the incisal edge of the lower incisor lies posterior to the cingulum of the upper incisor. There are twotypes:• Division I:the upper incisors are proclined or of an average inclina-tion and there is an increased overjet (Fig.2.2b).• Division II:the upper central incisors are retroclined (Fig.2.2c).• ClassIII:the incisal edges of the lower incisor lie anterior to the cingulum plateau of the upper incisors (Fig.2.2d). DENTAL OCCLUSION15 Factors causing malocclusionSkeletal factorsThe anteroposterior relationship between the upper and lower jaw has an inuence on the dental arches. This is best gauged through cephalomet-ric analysis of a lateral cephalogram (See E ‘Facial and skull radiography’, pp.56–9), which is outside the scope of this handbook, but can be sum-marized as follows:• Skeletal Ibase:the jaws are in their ideal anteroposterior relationship in occlusion.• Skeletal II base:the lower jaw in occlusion is positioned more posteriorly.• Skeletal III base:the lower jaw in occlusion is positioned more anteriorly.(a)(b)(c)(d)Fig.2.2 BSI classication of occlusion. Reproduced from Mitchell L, MitchellD, Oxford Handbook of Clinical Dentistry (5th edn), p.125 (Oxford:2009). With permission from Oxford UniversityPress. 16CHAPTER2 Basic knowledge16Genetic factors• Skeletal factors.• Tooth size and number.Metabolic factorsFor example, a pituitary adenoma secreting growth hormone can result in mandibular prognathism and progressive malocclusion usually presenting in middle to lateage.Environmental factors• Soft tissue factors:lips, cheeks, and tongue can either move or stabilize teeth overtime.• Habits:thumb/ nger sucking, pen biting,etc.• Trauma:fractured mandible or midface, traumatized dentition.• Temporomandibular joint (TMJ) dislocation.Local factors• Variation in number ofteeth.• Spacedteeth.Problems caused bymalocclusionTeethTeeth can break, become mobile, or wear; crowns or llings can be dis-placed, causing symptoms.SofttissueGums can recede, causing sensitivity.TemporomandibularjointPatients can develop symptoms such as clicking, grinding, locking, pain, trismus, headache, tinnitus, muscle fatigue and spasms, sinus/ eye pain, and neck/ backpain.FunctionalDiculty biting or chewing.Patient aesthetic concernsAltered appearance from the perceived ‘norm’.Psychosocial problemsLow condence, low mood. May be subject to bullying or harassment. DENTAL OCCLUSION17 18CHAPTER2 Basic knowledge18Anatomy ofthe oralcavity• For an overview of mouth and throat structures, see Fig. 2.3. Dental graduates will have an advantage here, as many medical anatomy courses will not have covered this in detail.• The oral cavity is split anatomically into twoparts:• The vestibule is the space between the lip/ cheeks and the teeth/ gingivae.• The mouth proper is the space within the dental arches.• The oral cavity includes the lips, the buccal mucosae, the teeth, the gingivae, anterior 2/ 3 of tongue, the oor of mouth, the retromolar trigone, and the hard palate.• Posteriorly, the oral cavity communicates with the oropharynx, which encompasses the posterior 1/ 3 of tongue, soft palate, the palatine tonsils, and the upper pharynx.GingivaeThe gums provide a soft tissue seal around the teeth. They consist of thicker attached keratinized gingivae, which include the embrasure spaces between the teeth as interdental papillae. The attached gingivae become non- attached (and non- keratinized) at the mucogingival junction, often clearly seen as a darker redline.EpiglottisValleculaBase of tongue(posterior third)Sulcus terminalisBody of tongue(anterior two-thirds)Median lingual sulcusPalatine tonsilLingual tonsilForamen caecumCircumvallate papillaeFungiform/liform papillaeFig.2.3 Gross anatomy of the dorsum of the tongue. Reproduced from Sengupta Aand Giles A, ‘Oral Complications of Cancer and its Management’ (2010) with permission from Oxford UniversityPress. ANATOMY OFTHE ORALCAVITY19 Teeth(See E ‘Anatomy of the teeth’, pp. 10–2.) See Fig.2.4.PalateHard palate (part oforal cavity)This is the bony anterior portion of the palate, formed by the palatine pro-cesses of the maxillae and the horizontal processes of the palatine bones. The nasopalatine nerve and sphenopalatine artery exit anteriorly through the incisive canal, and the greater palatine vessels and nerve exit posteriorly through the greater palatine foramina before running anteriorly beneath the palatal mucosa.Soft palate (part oforopharynx)This is the soft bromuscular posterior portion of the palate, extending from the posterior edge of the hard palate to form the uvula. It prevents food from going up the back of the nose on swallowing and also resonates during speech. Laterally, two arches of mucosa in continuation from the soft palate form the tonsillar fossae— the palatoglossal arch anteriorly and the palatopharyngeal arch posteriorly. The palatine tonsils lie in these fossae.TongueThe oral cavity includes the anterior 2/ 3 of tongue. The tongue posterior to the circumvallate papillae is considered to be part of the oropharynx, which may be signicant when planning treatment for cancers of this region (see Fig. 2.3). The tongue is a muscular organ involved in chewing (mastication), taste, swallowing (deglutition), speech (articulation), and oral cleansing. Labial frenumRugaeUvulaMolarsPremolarsCanineIncisorsPalatinetonsilIncisive papillaPalatopharyngeal archPalatoglossal archPillars of FaucesRetromolarpadBuccal frenumAlveolar process of mandibleFig.2.4 Gross anatomy of the oral cavity. Reproduced from Sengupta Aand Giles A, ‘Oral Complications of Cancer and its Management’ (2010) with permission from Oxford UniversityPress. 20CHAPTER2 Basic knowledge20It is composed of muscles covered with mucous membrane. The tongue has a dorsal and ventral surface, the dorsal surface of which is roughened due to the presence of lingual papillae or ‘taste buds’— fungiform and fusiform.The blood supply to the tongue is via the lingual artery, which arises from the external carotid artery and enters the tongue deep to the hypo- glossus muscle. Venous drainage is via the dorsal and deep lingual veins terminating in the internal jugularvein.The sensory nerve supply to the ANTERIOR 2/ 3 of the tongue is the lingual nerve branch of cranial nerve (CN) V3, and taste is via the chorda tympani branch of CNVII.The POSTERIOR 1/ 3 of the tongue is supplied by the glossopharyngeal nerve (CN IX) for sensation andtaste.The motor nerve supply is the hypoglossal nerve (CN XII) to all muscles except palatoglossus, which is innervated by the vagus nerve (CNX).Floor ofmouthIn the midline is the brous lingual frenum with two submandibular duct (Wharton’s duct) openings at its base— the sublingual caruncle. The sublingual glands sit beneath the thin mucosa and the multiple ducts of Rivinus drain saliva produced by the sublingual gland into the oor of the mouth. Afur-ther single sublingual duct, the duct of Bartholin, also drains bilaterally at the sublingual caruncle. Lingual veins draining the tongue lie supercially, and the lingual nerve runs just mesial to the sublingualgland.0 The oor of mouth tissues are loose and can swell quickly with cel-lulitis or oedema. This pushes the tongue upwards and backwards, and can obstruct the airway.Retromolar trigoneThis is the triangular area of mucosa behind the last standing lower molar. The pterygomandibular raphe, just mesial to the trigone, connects the pterygoid process to the mylohyoid ridge of the mandible, and it is here that the buccinator muscle of the mouth and the superior constrictor muscle of the oropharynx attach. Therefore the retromolar trigone can be seen as a ‘crossroads’ between the oral cavity, oropharynx, nasopharynx, buccinator space, and parapharyngealspace. ANATOMY OFTHE ORALCAVITY21 22CHAPTER2 Basic knowledge22Anatomy ofthe facial skeleton• The facial bones and cranium make up the skull (Fig. 2.5). The cranium encloses the brain, while the facial skeleton protects the eyes, nose, and mouth, acting as a ‘crumple zone’ to absorb potential force from trauma.• The facial skeletal structure and proportions dene the shape and individuality of the humanface.FrontalboneThis is the skeleton of the forehead. It articulates inferiorly with the nasal bones at the nasion and the zygomas at the zygomaticofrontal sutures. It also forms the roof of the orbit and superior orbital rim and contributes partly to the medial orbital wall. Within the frontal bone just above the nasion there are frontal air sinuses, which can fracture and crumple with trauma.TheorbitsThe orbit is a cone- shaped cavity, with its base anterior and the apex pos-terior. The orbits protect the globe of the eye, the associated muscles, nerves, vessels, and the lacrimal apparatus. The orbit has four walls and an apex, made up of the following facialbones.• Superior wall (thick)— frontal, lesser wing of sphenoid (nearapex).• Medial wall (thin)— ethmoid, frontal, lacrimal, lesser wing of sphenoid.• Inferior wall (thin)— maxilla, zygomatic, palatine.• Lateral wall (thick)— frontal process of zygomatic, greater wing of sphenoid.• Apex— optic canal through lesser wing of sphenoid.The nasoethmoidal complexThe bony part of the nose consistingof:• nasalbones• frontal processes of maxillae• nasal part of the frontalbone• perpendicular plate of the ethmoid• inferior conchae andvomer.The shape of the external nose is governed by dierences in the nasal car-tilages. It is divided into two chambers by the partly bony and cartilaginous nasal septum (see Fig. 2.6), the main components of whichare:• perpendicular plate of ethmoid— superior (this descends from the cribriform plate of the ethmoid which separates the nasal cavity from the anterior cranial fossa; a broken nose or nasoethmoidal complex can cause a dural tear and a cerebrospinal uid leak or can transmit infection from the nose into the brain meninges)• vomer— posteroinferior• septal cartilage— anterior.Within the lateral mass of the ethmoidal bone are ethmoid cells, which make up the ethmoid sinuses. If drainage is blocked, infection can pass from these cells through the fragile medial wall of the orbit and can cause (post- septal) periorbital cellulitis which, if not treated, can cause blindness. ANATOMY OFTHE FACIAL SKELETON23 Coronal sutureFrontalOrbital plate of frontalGreater wing ofsphenoidZygomaticMaxillaNasal conchaeMastoid processStyloid processCoronoid processHeadRamusBodyLesser wing ofsphenoidSupraorbital foramenOptic canalSuperior orbital ssureInferior orbital ssureInfraorbital foramenMental foramenFig.2.5 Anterior view of skull. Reproduced from Atkinson ME ‘Anatomy for Dental Students, 4th edition’ (2013) with permission from Oxford UniversityPress.NasofrontalspineFronto-ethmoidalsutureCribriformplateSphenoidalsutureAlavomerisSphenoidalprocessPerpendicularplate ifethmoidCartilaginousseptumVomerFig.2.6 Anatomy of the nasal septum. Reproduced from Warner G etal. ‘Oxford Specialist Handbook Otolaryngology and Head and Neck Surgery’ (2009) with permission from Oxford UniversityPress. 24CHAPTER2 Basic knowledge24The zygomatic complexThe zygomatic or malar bone forms the prominence of the cheek and also part of the lateral and inferior wall of the orbit. These bilateral bones have a central body with three processes— the frontal process, the temporal pro-cess, and the maxillary process. They can often fracture with lateral facial trauma and may become displaced which can cause malar attening, orbital dystopia, and trismus.The maxillaThe upper jaw is formed by the fused maxillae (see Fig. 2.7). Their alveolar prominences support the maxillary teeth. The fused maxillae form a pyram-idal shape, articulating bilaterally with the zygomatic bones and superiorly with the frontal bone and nasal bones. The maxilla also contributes to the oor of the orbits.Zygomatic processInfraorbital foramenInfratemporal surfaceAnterior surfaceAnterior nasalspineMedial surfaceAnterior nasalspineOpening of posterioralveolar canalsAlveolar processFrontal processPalatine processFrontal processMaxillary tuberosityMaxillary hiatus(opening intomaxillary sinus)Orbital surfaceInfraorbital groove(a)(b)Fig.2.7 The right maxilla. (a)Lateral view; (b)medial view. Reproduced from Atkinson ME ‘Anatomy for Dental Students, 4th edition’ (2013) with permission from Oxford UniversityPress. ANATOMY OFTHE FACIAL SKELETON25 The mandibleThe mandible forms the lower jaw and contributes to the temporomandib-ular joint. Its alveolar processes house the mandibular teeth. The mandible is a squared- o U- shape and so often fractures in more than one place. Fig. 2.8 and Fig. 2.9 show the various regions of the lower jaw, which are impor-tant when describing fractures (see E pp. 25–26). The inferior alveolar branch of the trigeminal nerve runs through the mandible, exiting anteriorly through the mental foramina which are located between the roots of the lower premolar teeth bilaterally (see E Fig. 2.5, p. 23). The condylar head of the mandible articulates within the glenoid fossa of the temporal bone, separated by an articular disc and controlled by ligaments and the muscles of mastication (see E Fig. 2.10, p. 26).Temporal crestRetromolar fossaSuperiorandinferiormental spinesor tuberclesDigastric fossaMandibular foramenSigmoid notchGroove for mylohyoidnerve and vesselsMylohyoid lineSubmandibular fossaSublingual fossaLingulaAngle of mandiblePterygoid foveaNeckRamusBodyOblique lineExternal oblique ridgeMental foramenHeadMental protuberanceCoronoid process(b)(a)Fig.2.8 The mandible. (a)Lateral view; (b)medial view. Reproduced from Atkinson ME ‘Anatomy for Dental Students, 4th edition’ (2013) with permission from Oxford UniversityPress. 26CHAPTER2 Basic knowledge26Pterygoid foveaRetromolar fossaHeadNeckTemporal crestMental tubercleCoronoid processExternal obliqueridgeGenial tuberclesMental foramenFig.2.9 Superior view of the mandible. Reproduced from Atkinson ME ‘Anatomy for Dental Students, 4th edition’ (2013) with permission from Oxford UniversityPress.Middle meningealarterySubmandibularganglionSubmandibularductSublingual glandGenioglossusPosteriorbelly of digastricStylohyoid muscleHypoglossal nerveHyoglossusLingual arteryLingual nerveAuriculotemporalnerveMedial pterygoidInferior alveolarnerveSphenomandibularligamentFig.2.10 The oral course of branches of the mandibular trigeminal seen in a lateral view of the oor of the mouth and its contents. Reproduced from Atkinson ME ‘Anatomy for Dental Students, 4th edition’ (2013) with permission from Oxford UniversityPress. ANATOMY OFTHE FACIAL SKELETON27 28CHAPTER2 Basic knowledge28Anatomy ofthe oral and facial muscles, nerves, andglandsMuscles• Facial muscles (Fig.2.11).• Muscles of mastication (Fig.2.12).NervesLingualnerveBranch of trigeminal (CN V); passes medial to the mandible, close to the posterior molar teeth into the posterolateral tongue where it supplies sen-sation to the anterior 2/ 3 of the tongue. It also lies in close apposition to the deep lobe of the submandibular gland. It crosses the submandibularduct.Inferior alveolar nerve (or inferior dental nerve(IDN))Branch of trigeminal (CN V); enters the mandible posteriorly at the lingua to pass through the body of the mandible anteriorly where it then exits via the mental foramen as the mental nerve to supply sensation to the lower lip and chin. It passes close to the apices of the posterior molar teeth and so can be damaged during dentoalveolar surgery.Frontal belly ofoccipitofrontalisOccipital belly ofoccipitofrontalisTemporalisZygomaticusmajorSternohyoidZygomaticusminorModiolusDepressor labiiinferiorisDepressoranguli orisOrbital part oforbicularis oculiPalpebral part oforbicularis oculiParotid duct (cut)MasseterLevator labiisuperiorisLevator anguliorisOrbicularisorisBuccinatorPlatysma (cut)SternocleidomastoidOmohyoidTrapeziusFig.2.11 The muscles of facial expression and other supercial muscles of the head and neck. Reproduced from Atkinson ME ‘Anatomy for Dental Students, 4th edition’ (2013) with permission from Oxford UniversityPress. 29 ANATOMY OFTHE ORAL & FACIAL MUSCLES, NERVES, &GLANDSSuperior temporal lineInferior temporal lineCentral tendonLateraltemporomandibularligamentLateral pterygoid(a)TemporalisMasseteric nerveMasseteric arteryMasseterDeep layerMiddle layerSupercial layerFacial artery(b)Articular discDeep temporalnervesMandibularcondyleUpper head oflateral pterygoidLower head oflateral pterygoidDeep head ofmedial pterygoidSupercial headof medialpterygoidPosterior superioralveolar nervesand vesselsInferior alveolarnerveSphenomandibularligamentMaxillary nerveand arteryBuccal nerveLingual nerve(c)Fig.2.12 Muscles of mastication:(a) masseter; (b)temporalis; (c)pterygoid muscles (coronoid process of mandible removed). Reproduced from Atkinson ME ‘Anatomy for Dental Students, 4th edition’ (2013) with permission from Oxford UniversityPress. 30CHAPTER2 Basic knowledge30FacialnerveThe facial nerve (CN VII) exits the skull base through the stylomastoid fora-men. As it passes through the parotid gland, it splits into ve main divisions: temporal, zygomatic, buccal, marginal mandibular, and cervical (Fig. 2.13). These branches supply facial movements— eyebrow raise/ frown, eye squint, cheeks,mouth.The marginal mandibular branch of CN VII runs just deep to the platysma and loops below the level of the mandible, which is why a skin excision (e.g. during submandibular gland excision or extra- oral drainage of a dentofacial abscess) should be made at least two nger breadths inferior to the mand-ible to avoid iatrogenic damage to this nerve. The facial nerve is also sensory to the upper pole of the tonsil and part of the external auditory meatus.GlandsParotidglandThis pyramid- shaped gland lies behind the angle of the mandible and in front of the ear, covered by a thick parotid fascia. Serous saliva produced by the gland is expressed into the mouth via Stenson’s duct at the parotid papilla inside the cheek opposite the upper second molar tooth. The gland con-tains the external carotid artery, which divides into the maxillary and super-cial temporal branches within the gland (deep to the facial nerve). Facial nerve division within the gland is described in the previous ‘Facial nerve’ section.• Innervation:glossopharyngeal nerve (CN IX) via auriculotemporal nerve— parasympathetic stimulation.• Blood supply:transverse facial artery.SubmandibularglandThis bi- lobed gland lies beneath the mandible just anterior to its angle. The supercial and deep lobes are separated by the posterior free edge of the mylohyoid. The gland produces mixed serous/ mucinous saliva, and this is expressed into the mouth via Wharton’s duct which runs from the deep lobe of the gland along the oor of the mouth to the papillae located either side of the tongue frenum.• Innervation:parasympathetic supply is via chorda tympani (CN VII), then joining the lingual nerve (CN V3) and synapsing on the submandibular ganglion.• Blood supply:facial artery. 31 Posteriorauricular branchTemporal branchZygomaticbranchesBuccalbranchesMandibularbranchCervicalbranchFig.2.13 The facial nerve and its branches on the face. Reproduced from Atkinson ME ‘Anatomy for Dental Students, 4th edition’ (2013) with permission from Oxford UniversityPress.ANATOMY OFTHE ORAL & FACIAL MUSCLES, NERVES, &GLANDS 32CHAPTER2 Basic knowledge32Anatomy oftheneckSurface anatomyThe sternocleidomastoid muscle (SCM) is the key anatomical landmark in the neck, splitting it diagonally into anterior and posterior triangles, with the trapezius muscles making up the posterior aspect of the neck. Further triangle subdivisions are described (Fig.2.14).Within the triangles of the neck, various supercial structures can be seen or palpated (Fig. 2.15). It is worth knowing the neck landmarks for emergency procedures, such as a needle or surgical cricothyroidectomy, and for other elective operations, such as tracheostomy, thyroidectomy, and subman-dibular gland excision, which are described in the emergency and operative chapters of this handbook.FasciallayersSupercial cervicalfasciaThis is a subcutaneous connective tissue layer containing the platysma, cuta-neous nerves, blood vessels, and lymphatics.Deep cervicalfascia• The investing fascia surrounds all the structures in theneck.• The prevertebral fascia divides the neck into anterior and posterior compartments. The posterior compartment contains the vertebral column and its associated muscles. Deep to this fascia is the phrenic nerve (C3– C5) and brachial plexus.• The anterior compartment contains further deep fascial envelopes:• The pre- tracheal fascia encloses the thyroid, trachea, pharynx, and oesophagus.• The carotid sheath encases the common and internal carotid arteries, the internal jugular vein, the vagus nerve (CN X), the deep cervical lymph nodes, the carotid sinus nerve, and sympathetic bres.The deep fascial layers form natural cleavage planes through which tissues may be separated during surgery. They limit spread of abscesses resulting from infections, and allow structures to move and slide over each other when twisting the neck or swallowing. It is important to have a good work-ing knowledge of the fascial spaces of the neck for better understanding of the spread of dentofacial infections (Fig.2.15).MusclesPlatysmaOriginates from fascia of pectoralis major/ deltoid and inserts into tip of chin and mandible. Fibres also blend with those of muscles of lower face. Innervation:cervical branch of CN VII (on its deep surface). Actions:draws corners of mouth down and depresses mandible. Soft tissue injuries that penetrate this muscle layer must be explored in theatre.SternocleidomastoidRotates head to opposite side. Originates from mastoid process of tem-poral bone, inserts into manubrium and clavicle. Innervation:spinal root of accessory nerve (CN XI) andC2/ C3. ANATOMY OFTHENECK33 OesophagusTracheaLigamentum nuchaeThyroid glandAnterior jugular veinExternal jugular veinInternal jugular veinVagus nerveOmohyoidCommon carotid arteryFlexor vertebral musclePlatysmaSternocleidomastoidCervical spinal nerveVertebral arteryTrapeziusExtensor vertebralmusclesScalene musclesAccessory nerveInvesting fasciaSternothyroidSternohyoidFig.2.15 The arrangement of the deep fascia of the neck shown on a horizontal section at the level of the sixth cervical vertebra. Reproduced from Atkinson ME ‘Anatomy for Dental Students, 4th edition’ (2013) with permission from Oxford UniversityPress.Digastric(posterior belly)TrapeziusDigastric (anteriorbelly)AnteriortriangleDigastrictriangleCarotidtriangleMusculartriangleOmohyoidSternocleidomastoidPosterior triangleFig.2.14 The muscular triangles of the neck. Reproduced with permission from Ellis Hand Mahadevan V, Clinical Anatomy, Thirteenth Edition, Wiley- Blackwell, Oxford, UK, Copyright ©2013. 34CHAPTER2 Basic knowledge34Suprahyoid and infrahyoid (strap) musclesSee Fig.2.16.GlandsThyroidglandThis gland saddles the larynx and the trachea and is surrounded by the pre-tracheal fascia. It consists of two lobes joined in the midline by the isthmus. It is a highly vascular gland supplied by the superior and inferior thyroid arteries and occasionally a third innominate or ‘thyroid ima’ artery (71%) which can run directly o the arch of aorta supplying the gland from below. This can present a problem during tracheostomy.The paired recurrent laryngeal nerves are located just posterior to the thyroid gland and can be damaged by thyroid surgery or invaded by thyroid malignancy, causing a weak, breathy voice. Innervation is via the cervical sympathetic ganglia.ParathyroidglandsThese vary in position and number. They are usually found embedded on the posterior aspect of the thyroid lobes. If performing a total thyroidec-tomy, the parathyroid glands (not always possible to preserve all four) must be located and left with their blood supply as removal will cause hypocal-caemia. Asubtotal thyroidectomy would aim to preserve the parathyroid glands by leaving a posterior cu of thyroid tissue.• Blood supply:inferior thyroid arteries.• Innervation:via cervical sympathetic ganglia.Lymphatics oftheneck• Supercial cervical lymph nodes are located along the external and internal jugular veins. They drain into the deep cervicalnodes.• Deep cervical lymph nodes form a chain along the internal jugular vein, mostly under cover of theSCM.• Other deep lymph node groups include the pre- laryngeal, pre- tracheal, para- tracheal, and retro- pharyngeal lymphnodes.The lymph nodes of the neck are often classied according to their anatomi-cal level within the neck (Fig.2.17). ANATOMY OFTHENECK35 Scalene musclesThyroid glandOmohyoidSternocleidomastoidSternothyroidAnteriorbelly of digastricPosteriorbelly of digastricStylohyoidHyoid boneThyroid cartilageSternohyoidMylohyoidMedian rapheTrapeziusClavicleMandibleFig.2.16 The infrahyoid muscles and some of the suprahyoid muscles. The right sternocleidomastoid has been removed for clarity. Reproduced from Atkinson ME ‘Anatomy for Dental Students, 4th edition’ (2013) with permission from Oxford UniversityPress.IIIIIIVIVFig.2.17 Lymph node levels in the neck. Reproduced from Corbridge R, Steventon N, Oxford Handbook of ENT and Head and Neck Surgery, p.263 (Oxford:2010). With permission from Oxford UniversityPress. 36CHAPTER2 Basic knowledge36Medical ‘clerking’:history and full body examination• Clerking of patients is an important job for juniors when admitting emergency and elective patients, and although the ‘knowledge comfort zone’ may be focused on the teeth, head, and neck, a full- body systematic approach is essential.• The more you practise, the slicker you will become at doingthis.• Remember that any new information you uncover from the ‘clerking’ that may be relevant should be brought to the attention of your senior, as the patient may require further investigation prior to receiving an anaesthetic, or indeed an operation.HistoryPresenting complaintOne line— what is/ are the patient’s main complaint(s)?History ofpresenting complaintFurther details of complaint(s) similar to taking pain history. Include onset, site, character, associated symptoms, relieving/ exacerbating factors, as well as any relevant focused information regarding the current problem. Acronym for pain history:SOCRATES— Site, Onset, Character, Radiation, Associated factors (e.g. nausea and sweating), Timing, Exacerbating/ reliev-ing factors, Severity.Past medical history• Thorough details of other medical problems, when they were diagnosed, if relevant which doctor/ department treated them and how they were treated.• Run through the other body systems in turn to check the patient has not forgotten anything.Drug historyUp- to- date list including dosages. Record all allergies.Social history• Occupation.• Social home arrangements.• Smoking (in pack- years— 1 pack- year=smoking 20 cigarettes a day for 1year).• Alcohol (units perweek).• Recreationaldrugs.Family historyAny genetic conditions— e.g. sickle cell disease, Fanconi anaemia, Gardner syndrome, basal cell nevus syndrome, malignant hyperpyrexia (implications for anaesthetic). MEDICAL ‘CLERKING’:HISTORY AND FULL BODY EXAMINATION 37 Examination• Wash yourhands.• Position the patient at 45° in bed (at for abdominalexam).• Have a methodical approach:• Inspect• Palpate• Percuss• Auscultate.• Always ask the patient if an area is painful to touch and be extra gentleifso. It is advisable to have a chaperone present whenever you are examining a patient to protect both yourself and your patients.General inspection• Record how the patient looks from the end of the bed— comfortable, in pain, distressed, comatose,etc.• Record all current observations (heart rate, BP, respiratory rate, O2 sats, and temperature).• Record Glasgow Coma Scale score and whether patient is orientated to time andplace.Cardiovascular• Inspect— look for nail clubbing, distended veins in the neck, scars to chest wall, pacemaker. Look for ankleoedema• Palpate— measure capillary rell. Palpate radial pulse— rhythm, rate. Feel apexbeat.• Auscultate— use the diaphragm of the stethoscope in four areas. Listen for two heart sounds— ‘lub- dub’ (1st heart sound=mitral valve closing, 2nd heart sound=aortic and pulmonary valves closing). Listen for murmurs (drawn out sounds), as these could indicate valve dysfunction.Respiratory• Inspect— clubbing of ngernails, nicotine staining. Chest wall scars. Breathlessness, oxygen. Respiratory rate and character.• Palpate— for tracheal deviation and whether lungs are expanding equally.• Percuss— ask a senior to show you how to do this. Adull sound suggests uid or consolidation.• Auscultate— use the bell of the stethoscope. Compare left and right elds and listen anteriorly and posteriorly. Listen for crackles— pulmonary oedema/ uid, or wheeze— asthma or reduced breath sounds— consolidation/ pathology.Abdominal• Inspect— abdominal scars/ masses, is the patient jaundiced?• Palpate— lie patient at and feel (gently) in all nine regions of the abdomen. Feel for masses, or tenderness. Feel for the lower edge of the liver by asking the patient to breathe in and running the edge of your hand up towards the lower portion of the right rib cage. If enlarged, it suggests hepatomegaly. 38CHAPTER2 Basic knowledge38• Percuss— ascitic uid can be identied by percussing from the midline to the ank, the sound changing from tympanic to dull. Adistended bladder can also be percussed.• Auscultate— listen for normal bowel sounds (gurgling every 5– 10 seconds) within 30 seconds. If absent or increased, it suggests ileus or obstruction, respectively.Neurological• Assessment of tone, power, coordination, reexes, and sensation in all four limbs. Sensation should be tested for light touch, pain, temperature, proprioception, and vibration. Gait should also be assessed.• Cranial nerve examination.11 Wilkinson IA, Raine T, Wiles K, etal. 2017. Cranial nerve examination. In:Oxford Handbook of Clinical Medicine (10th ed), p.70. Oxford:Oxford UniversityPress. MEDICAL ‘CLERKING’:HISTORY AND FULL BODY EXAMINATION 39 40CHAPTER2 Basic knowledge40Examination ofthe oralcavityThe oral cavity extends from the vermilion border of the lips to the anterior pillar of fauces where it becomes the oropharynx. Although the tonsils are in the oropharynx, it is good practice to examine themalso.Examination of the neck is mandatory in conjunction with the oral cavity. If you examine the neck rst, you won’t forget to do so afterwards. Record both positive and negative ndings.The keys to good oral examinationare:• be systematic• weargloves• get a good lightsource• have gauze and suction available• support thehead• extend theneck• be calm and gentle, and tell the patient what you are abouttodo• enquire if the tissues are painful before starting to examine• use tongue spatulas or dental mirrors for retraction• be aware of the gag reex.Examination• Look rst using two mirrors or spatulas to retract the cheeks or lips as you will see more if you keep your hands out of theway.• Examine the lips, buccal mucosa, hard and soft palate, gingivae, teeth, retromolar trigone, tonsils, and dorsal tongue.• Hold the tongue- end with gauze and, with the patient’s help, move it to one side and examine the oor of the mouth and the posterior oral tongue, although the pharyngeal tongue examination requires nasendoscopy.• Mucosal lesions may be better examined after drying withgauze.• Palpate any lesions you nd. Texture is important (the hard ‘grittiness’ of malignancy is a valuablesign).• Palpate the lips, cheeks, and tongue, especially the base of tongue.• The oor of the mouth and the submandibular gland are best palpated bimanually (gloved nger of one hand inside the mouth and other hand pressing up from theneck).• Milk saliva from the parotid and submandibular glands, looking for volume, consistency, and pus or debris.• Examine cranial nerves, especially facial, trigeminal, hypoglossal and palatopharyngeal plexus.AdditionaltestsVitality testing ofteethUsing an electric pulp tester or just ethyl chloride sprayed onto a cotton wool pledget placed onto the tooth surface will give you an indication of whether the pulp is alive or dead (not always reliable). EXAMINATION OFTHE ORALCAVITY41 Percussion ofteethThis will be painful if there is periapical or lateral inammation of the PDL, such as acute apical periodontitis secondary to pulpal infection. NB: the PDL must be inamed for the tooth to be tender on percussion. If infec-tion is conned to the pulp only (i.e. pulpitis), percussion may not evoke a positive response.Use ofprobesProbes can be used to investigate periodontal pockets as well as periodon-tal sinuses. Occasionally a gutta percha point carefully inserted into a sinus followed by a periapical radiograph will show the source of the sinus. This technique can also be useful in conrming a small oroantral stula.Small lacrimal probes can also be used to dilate salivary ducts and strictures.RadiographsUseful for dental disease, bone lesions, soft tissue foreign bodies, and salivary calculi. Many departments have equipment in the clinic (see E Chapter3, ‘Radiology’).NasendoscopyUnidentied neck lumps and head and neck cancer referrals often neces-sitate a nasendoscopy (see E p. 238). 42CHAPTER2 Basic knowledge42Examination ofthe face andneck• Be systematic. Try to adopt a structured approach so that pathology is not missed.• As always, good light and access will help, and if there is a dental chair available, use it. You can then recline the patient and walk around the head- end, easily examining from dierent angles.• Always note down examination ndings in detail, as the clinical picture can often change withtime.ThefaceSoft tissuesA close inspection of the soft tissues is required rst, bearing in mind that signs of trauma and pathology can often be missed within the patient’s hair and around the ears. Examine for asymmetry, masses, scars, or deform-ity. Having established if the patient is tender anywhere, palpate the soft tissues, gently comparing each side of the midline. If a swelling or mass is present, note the following:• Site, size, shape, surface, colour, temperature, consistency, uctuance, xity, and pulsatility, and whether there are other associated signs such as a punctum or local lymphadenopathy.• With any abnormality on the skin surface, immediately think about associated deeper anatomy such as bones, muscles, nerves, blood vessels, lymphatics, and underlying glands orducts.Hard tissuesThe facial skeleton should be examined systematically, bearing in mind that there may be signs pointing to fractures in the overlying soft tissues, such as contusion, bruising, haematoma, swelling, laceration, and crepitus.When palpating the facial bones, compare both sides of the face, feeling for step deformities, depressions, movement, or sharp bone fractureends.Eyes• Examine the eyes for abnormalities of the sclera, iris, andpupil.• Asubconjunctival haemorrhage is an important sign to note, particularly if there is no posterior limit to the haemorrhage, as it may mean there is an orbital wall fracture.• Pupillary reexes, eye movements, and fundoscopy should be examined as part of the cranial nerve examination.• Visual acuity should always be recorded for any trauma involving the eye or surrounding facial tissues.• Examine the conjunctivae and eyelids. Look for proptosis, lid retraction, or ptosis.• Check intercanthal distance and interpupillary distance.Nose• Look externally for deformity, asymmetry, or skin lesions.• Look internally for septal deviation or haematoma. Assess air entry bilaterally. Check for signs of bleeding or discharge. EXAMINATION OFTHE FACE ANDNECK43 Ears• Look for deformity, haematoma, or skin lesions.• Use an auroscope to look into the ear, check that the auditory canal is patent, and that the tympanic membrane is intact.• Check for signs of bleeding or discharge.TheneckExaminationsteps• Inspect from the front and the side before standing behind the patient to palpate the neck. Ask the patient to swallow (thyroidmass).• Use two hands to palpate left and right sides simultaneously for comparison.• Move methodically to palpate all lymphatic chains, starting under the chin and moving backward to palpate the submandibular region.• The submandibular gland must be dierentiated from submandibular nodes. The gland can often be appreciated better by placing a gloved nger in the oor of mouth so that it can be palpated bimanually.• Continue to examine over the angle of mandible, the pre- auricular and parotid region, and the post- auricular region, and then move down the SCM muscle.• Try to displace the muscle gently so that deeper nodes are not missed.• Don’t forget the supraclavicular areas, before carefully examining the midline and thyroidgland.• Finish by examining the posterior triangle of the neck (see E Fig. 2.14, p. 33).Thyroid gland examinationExamination of the thyroid requires a specic approach in addition to the neck examination, and is an examiner’s favourite.• Look at the skin in general and hair quality, including the lateral third of the eyebrows, which can be lost in hypothyroidism.• Look at the eyes for signs of exophthalmos or lid lag seen in hyperthyroidism.• Ask the patient to swallow, inspecting the neck from the front. Athyroid mass will rise during swallowing. Check for any scars of previous surgery.• The gland should be palpated from behind, comparing the right and left lobes and the isthmus between them. Anormal gland will most likely be impalpable.• Distinguish any other midline neck swelling from what could be a thyroid isthmus swelling, e.g. a thyroglossal cyst will rise when a patient protrudes their tongue rather than on swallowing.• Percussion may identify a goitre with retrosternal extension.• Auscultate for bruits associated with vascular hyperactive thyroid glands.• Other thyroid- specic examination points are to listen to the voice (a weak, hoarse, or breathy voice might indicate a recurrent laryngeal nerve palsy from invading malignancy or previous surgery) and examine the hands (sweaty palms or a resting tremor could indicate hyperthyroidism). 44

Related Articles

Leave A Comment?