Year 2 Flashcards
1
Q
4 basic components of dental anlog x-ray films?
A
Film base
Adhesive layer
Film emulsion (silver halide crystals in gelatin matrix)
Protective layer
2
Q
What are the 5 basic sizes for intraoral film packets?
A
#0: child IOPA, BW #1: Adult ant IOPA, mixed dentition BW #2: Adult IOPA, BW, child occlusal #3: extralong BW #4: occlusal in adults
3
Q
What is an intensifying screen?
A
Contains phosphors that emit visible light when struck with x-ray photons. Results in lowered patient doses but resolution is reduced.
4
Q
What are the 2 types of digital image receptors?
A
Solid state (direct) PSP (semi-direct)
5
Q
What are the angles and point of entries for maxillary teeth?
A
- Mx incisors : +50, tip of nose
- Mx canines: +50, ala of nose
- Mx premolars: +30, level of pupil & close to the ala tragus line
- Mx molars: +25, outer canthus of eye, over cheek and below zygoma
6
Q
What are the angles and point of entries for mandibular teeth?
A
- Md incisors: -20, tip of chin
- Md canine: -20, 2cm D to tip of chin
- Md premolars: -15, level of pupil, 3cm above lower border of md
- Md molars: -5, level of outer canthus of eye, 3cm above lower border of md.
7
Q
What is paralleling technique?
A
Film is parallel to long axis of tooth and x-ray tube is right angles to tooth and film
8
Q
What are the steps of processing conventional films?
A
- Development
- Rinsing
- Fixing
- Washing
- Drying
9
Q
What is the principle of panoramic radiography?
A
Reciprocal movement of an X-ray source and a image receptor around a central plane, called the image layer (focal trough).
- The object of interest is located in the image layer
- Objects in front or behind this image layer are blurred out
10
Q
What are examples of double real images?
A
Produced by structures located in the midline (x-ray beam passes through it 2x).
- Hard palate
- Soft palate
- Hyoid bone
- Spine
11
Q
Describe features of ghost image
A
- Opposite side
- Same shape
- Less distinct
- Larger
- Projected higher
12
Q
What is the time-distance-shielding principle?
A
- Reduced exposure time
- Increased distance form source (as distance doubles, intensity reduces by factor of 4)
- Shielding using lead barriers
13
Q
What is the flow rate for water coolant?
A
35-50mL/min
14
Q
What salivary gland contributes the most?
A
Submandibular gland
15
Q
What is a mucocele?
A
Pooling of saliva in damaged or obstructed minor salivary gland duct.
16
Q
What is sialolithiasis?
A
Calcified or organic matter in parenchyma or ducts of salivary glands (infection, swelling, mealtime discomfort)
17
Q
What is mumps?
A
Fever, malaise, trismus, gland swelling
Common in parotid gland
18
Q
What is juvenile recurrent parotitis?
A
- Disease in children
- Uni or bilateral parotid swellings
- Pain, fever, redness of skin overlying gland
19
Q
What is sjorgren’s syndrome?
A
- Chronic autoimmune disorder that causes dry eyes and mouth (affects all exocrine glands)
- Primary: no connective tissue disease
- Secondary: connective tissue disease or rheumatoid arthritis
20
Q
What is sialosis?
A
Bilateral and painless enlargements of parotid glands
21
Q
What is ectodermal dysplasia?
A
- Hair, glands, teeth, skin, nails affected
- Conical shaped teeth
22
Q
What is amelogenesis imperfecta and the 3 types?
A
Alteration in enamel structure in absence of systemic disorder
- Hypoplastic (pin points)
- Hypomaturation (white capped enamel)
- Hypocalcification (brittle, chalky)
23
Q
What is dentinogenesis imperfecta?
A
Disturbance in dentine in absence of systemic disorder
- Type I: assoc with osteogenesis imperfecta
- Type II: not assoc with osteogenesis imperfecta
- Type III: bradwine type
24
Q
What is regional odonto-dysplasia?
A
- Small irregular crowns with rough surface
- Large pulp chamber
25
What are the stress bearing areas on mandibular edentulous ridge?
* Buccal shelves
* Retromolar pads
* Alveolar ridge
26
What are the stress bearing areas on maxillary edentulous ridge?
* Firm tuberosities
* Hard palate
* Alveolar ridge
* Rugae
27
What is combination syndrome?
* Anterior part of mx edentulous ridge becomes mobile and resilient as fibrous tissue replaces underlying bone.
* Over eruption of lower anterior teeth
* Resorption of md distal extension area
* Decreased VDO
* Hypertrophy of tissues in mx tuberosities
28
What medications cause gingival hyperplasia?
* Phenytoin
* Sodium valproate
* Cyclosporin A
29
What are modifiable vs non-modifiable risk factors for oral cancer?
* Non modifiable: age, ethnicity, SES
* Modifiable: smoking, alcohol consumption, diet, lifestyle, betel quid
30
How does cartilage grow?
* Hyperplasia
* Hypertrophy
* Extracellular material deposition
(cartilage does the growing and bone replaces it)
31
What are the 6 fontanelles?
* Anterior
* Posterior
* Sphenoid (paired)
* Mastoid (paired)
32
What is the growth mechanism of cranial base vs cranial vault?
* Cranial base: endochondral ossification
* Cranial vault: intramembranous ossification
33
Describe remodelling of maxilla
Maxilla is connected to cranial base so it moves forward until age of 7 when cranial base growth stops. After this, the maxilla moves forwards and downwards from intramembranous ossification at the sutures. There is resorption of the anterior surface of the maxilla.
34
Describe formation of mandible
There is condensation of mesenchyme around meckels cartilage. The meckels cartilage disintegrates and bone replaces it. The condylar head is the only part of the mandible that grows via endochondral ossification.
35
What are 1st and 2nd arch muscles?
* 1st arch: muscles of mastication (temporalis, masseter, medial and lateral pterygoid)- 5th nerve
* 2nd arch: muscles of facial expression (frontalis, occipitalis, buccinator, obicularis oris)- 7th nerve
36
Layers of scalp
* Skin
* Connective tissue (dense)
* Aponeurosis
* Loose connective tissue
* Periosteum
37
What layer does blood and pus collect in skull?
Loose connective tissue (dangerous as infection can spread intracranially through veins)
38
What are the 3 divisions of the trigeminal nerve?
* Ophthalmic
* Maxillary
* Mandibular
39
What nerve innervates the TMJ?
Mandibular nerve (auricular temporal branch)
40
What are the branches of the mandibular nerve?
* Lingual nerve
* Inferior alveolar nerve
* Nerve to mylohyoid
41
What 4 muscles are innervated with V3?
* Temporalis
* Medial and lateral pterygoid
* Masseter
42
What nerve provides innervation to the tongue?
* Anterior 2/3 general sense: lingual branch of V3
* Anterior 2/3 taste: chroda tympani
* Posterior 1/3 sense: glossopharyngeal
* Muscles: hypoglossal
43
What 5 blood vessels provide the skull with blood?
* Supratrochlear
* Supraorbital
* Superficial temporal
* Posterior auricular
* Occipital
44
Explain the importance of danger triangle of the face?
Area between root of nose and angles of mouth. Veins that drain this region are connected to cavernous sinus and valveless. If infection reaches this area, cavernous sinus thrombosis can occur (nerves III, IV, V1, V2 and internal carotid artery run through cavernous sinus and would be affected)
45
What are the branches of the facial nerve?
* Posterior auricular
* Temporal
* Zygomatic
* Buccal
* Marginal mandibular
* Cervical
46
Signs of bells palsy
* Droop on one side of face due to damage to facial nerve
* Loss of taste sensation to anterior ⅔ of tongue
47
What is the innervation of the intrinsic muscles of the tongue?
Hypoglossal nerve
48
What is the sensory supply of posterior ⅓ of tongue?
Glossopharyngeal nerve (IX)
49
What is the sensory supply to anterior ⅔ of tongue?
Temp pain: lingual nerve (V3)
Special: chorda tympani (runs with facial nerve)
50
What nerve is at risk of damage when there is a mandible fracture?
Hypoglossal (XII)- tongue will deviate to side of damage
51
What does the lingual artery supply?
* Sublingual and submandibular salivary glands
* Muscles of tongue
52
What is the danger zone for spread of infection through spaces?
Retropharyngeal space- infection can spread to superior mediastinum of thorax
53
What is Ludwig's Angina?
Involves spread of infection from mandibular teeth to one space initially. If infection spreads to retropharyngeal space, oedema of larynx can cause complete respiratory obstruction
54
What is the difference between C-fibres and Aδ fibres?
C-fibres: fine, slow conducting non-myelinated nerves- dull burning pain. Associated with skin, deep tissue and organ systems.. Associated with skin (superficial)
Aδ fibres: fine, myelinated fibres, conduct more rapidly- sharp, well-localised pain
55
What are the 8 branches of the external carotid artery?
* Superior thyroid
* Ascending pharyngeal
* Lingual
* Facial
* Occipital
* Posterior auricular
* Maxillary
* Superficial temporal
56
What is the parotid gland innervated by?
IX
57
What does the maxillary artery supply?
Nasal cavity, lateral wall and roof of the oral cavity, muscles of mastication, all teeth and dura mater in cranial cavity.
58
What are the 3 parts of the maxillary artery?
1. Mandibular
2. Pterygoid
3. Pterygopalatine
59
What are the maxillary teeth supplied by?
Pterygopalatine part of maxillary artery.
* Posterior superior alveolar arteries supply the molars.
* Whilst in infraorbital foramen, infraorbital artery gives off the middle and anterior superior arteries that supply the premolars and anterior teeth respectfully
60
What BP indicates it's unsafe to proceed?
SBP: \>180mmHg
DBP: \>110mmHg
61
What is xerostomia vs salivary hypofunction?
Xerostomia: subjective feeling of oral dryness
Salivary hypofunction: reduced saliva flow
62
What medications are used for patients with arrythmias?
* Amiodarone
* NOACs
Best to not use adrenaline in these patients
63
What drugs interact with asthmatic patients?
Aspirin
NSAIDs
Opiates
Macrolides- can interact with theophylline
Sulphite drugs
64
What are drug interactions with epileptic medications?
* Antibiotics: erythromycins and metronidazole inhibit metabolism of anticonvulsants
* Azoles (anti-fungal): interactions with sodium valproate, phenytoin, carbamazepine
* NSAIDs: use with sodium valproate can exacerbate bleeding
65
What are oral considerations for parkinson's disease?
* Decreased dexterity
* Levodopa can cause xerostomia, nausea, oral burning
* Poor denture retention
* Excess salivation
* Avoid use of adrenaline in pts taking MAOIs
66
What are the patterns of erosion from vomiting?
* Smoothened cupped occlusal/incisal lesions
* Concave buccal surfaces
* Palatal surfaces affected
* Smooth, shiny and generalised loss of anatomy
67
What are oral considerations of diabetes?
* Risk of hypoglycaemia
* Salivary dysfunction
* Glossitis (BMS)
* Candidosis
* Angular cheilitis
* Periodontal disease
* Give patients paracetamol or codeine rather than NSAIDs (esp renal impairment)
68
What patients should we avoid giving adrenaline?
* Patients with hyperthyroidism
* Patients taking MAOIs
69
What does lithium interact with?
NSAIDs
Metronidazole
Tetracyclines
Diazepam
70
When is the best timing for extracts in dialysis patients? Why?
Best time for exo on nondialysis day. (dialysis causes blood to clot and heparin is taken to prevent this )
71
What are the Kennedy classes?
* Class I: bilateral edentulous areas posterior to all remaining teeth
* Class II: unilateral edentulous area located posterior to all remaining teeth
* Class III: unilateral edentulous area bounded by ant and post natural teeth
* Class IV: single, bilateral edentulous area anterior to remaining teeth
72
What are requirement of a major conenctor?
* Rigidity
* Non-interference with tissues
* Avoid terminating on FGM, tori, frenum, movable soft palate
73
What is a single palatal strap used for?
Bilateral short span edentulous areas (Kennedy class III)
74
What is anterior-posterior palatal strap used for?
* Class II and IV (can be used for almost any mx partial denture design)
* Presence of tori
75
When is a palatal plate type connector used?
Class I (last remaining tooth being canine or 1st premolar)
76
When is lingual bar used?
* Simplest and most commonly used lower major connector
* Use when possible
* Most hygienic
* Most comfortable
* Needs min 7mm from FGM to FOM
77
When is a lingual plate used?
* If lingual vestibule \<7mm
* Prominent lingual frenum or tori
* Anterior teeth perio compromised
* When all post teeth are to be replaced bilaterally
Don't use when there is severe anterior crowding
78
What is stability, support and retention?
* Support: resistance to movement toward tissues/teeth (rest)
* Retention: resistance to removal from tissues/teeth
* Stability: resistance to movement in the horizontal plane
79
What undercutz are co-cr, gold and stainless steel clasps suited to?
Co-cr: 0.25mm
Gold: 0.5mm
Stainless steel: 0.75mm
80
When should stress-releasing direct retainers be used? What are some examples of clasps?
* Distal extension
* Abutment periodontally involved
* Extensive edentulous space
RPI, RPA and combination clasp
81
What is RPI?
Mesial rest, proximal plate, I-bar
| (stops destructive forces on tooth)
82
What is the difference between mesh and lattice type gridwork?
Mesh: flatter, less retention
Lattice: thick struts, superior retention
83
Where should indirect retainers be placed?
Perpendicular to fulcrum line, as far as practical (often on premolars and canines)
(class I and II kennedy classes)
84
Role of sutures in skull?
* Absorb force of impact
* Accommodate growing brain
* Facilitate passage through birth canal
85
What are the cranial bones?
* Occipital
* Frontal
* Sphenoid
* Ethmoid
* Parietal
* Temporal
86
What are the facial bones?
* Palatine
* Lacrimal
* Nasal
* Inferior nasal conchae
* Zygomatic
* Maxillary
* Mandible
* Vomer
87
What are the 4 processes of the maxilla?
* Frontal
* Zygomatic
* Alveolar
* Palatine
88
Where do the crania nerves exit the cranial base?
* I: Cribriform plate
* II: optic canal
* III, IV, V1, VI: Superior orbital fissure:
* V2: F. rotundum
* V3: F. ovale
* VII, VIII: internal acoustic meatus
* IX, X, XI: jugular foramen
* XII: hypoglossal canal
89
Label the following strucutres
90
Describe innervation of maxillary teeth and supporting structures?
* Post sup alveolar: 2nd & 3rd molars, B gingiva and D-B & P root of 1st molar
* Middle sup alveolar: MB root of 1st molar, mx premolars, B gingiva
* Ant sup alveolar: Canines & incisors, B gingiva
* Greater palatine: P gingiva (distal to canine), mucosa of post ⅔ of hard palate on given side
* Lesser palatine: Mucosa on soft palate and uvula on given side
* Nasopalatine: P gingiva of incisors & canines, mucosa of ant ⅓ of hard palate
91
What do the middle and anterior superior alveolar nerves branch from?
Infraorbital nerve in infraorbital canal
92
What is a risk when blocking posterior superior alveolar nerve?
Risk of injecting pterygoid plexus of veins and maxillary artery if injected too far posterior
93
Compare properties of mx vs md
Mx: thin cortical bone, many nutrient canals, zygomatic buttress may prevent diffusion of LA to B roots of Mx 1st molar, close to pterygoid venus plexus posteriorly
Md: thick cortical bone, few nutrient canals, number of muscle attachments,
94
What are the branches of V3?
* Branches to muscles of mastication
* Buccal n
* IAN (mylohyoid, mental, incisive)
* Lingual
* Auriculotemporal
95
What is the pathway of IAN?
Travels obliquely downwards through infratemporal space and enters md at mandibular foramen. Before entering it gives of mylohyoid nerve.
96
Describe innervation of mandibular teeth and supporting structures?
* IAN: all teeth and supporting structures (except molar gingiva)
* Incisive: Teeth and supporting structures anterior to mental foramen
* Mental: mucosa of vestibulum and lower lip anterior to mental f.
* Buccal: B gingiva of molars
* Lingual: mucosa of FOM, anterior ⅔ of tongue and lingual gingiva of all teeth.
97
What are the pterygomandibular raphe attachments?
Attaches to pterygoid hamulus and mylohyoid line inferiorly. Medial landmark for LA
98
What are important structures to consider in pterygomandibular space when administering LA?
* Maxillary a. and branches
* Pterygoid venous plexus
* Sphenomandibular ligament
* Loose connective tissue
99
What is the position of IAN block?
Halfway between coronoid notch and pterygomandibular raphe, 1cm above occlusal plane of md teeth.
100
What are the 4 paranal sinuses?
Frontal
Maxillary
Ethmoid
Sphenoid
101
What is the origin, insertion, action and innervation of temporalis?
* O: temporal fossa & fascia
* I: coronoid process, anterior border of ramus
* A: elevates and retrudes the mandible
* N: V3
102
What is the origin, insertion, action and innervation of masseter (superficial and deep head)?
Sup:
* O: anterior ⅔ of zygomatic arch
* I: angle of md
* A: elevation and protrusion
* N: V3
Deep:
* O: medial border of post ⅓ of zygomatic arch
* I: angle and ramus of md
* A: elevation and retraction
* N: V3
103
What is the origin, insertion, action and innervation of medial pterygoid muscle (deep and superficial head)?
Deep head:
* O: medial surface of lateral pterygoid plate of sphenoid
* I: medial surface of ramus and angle of md
* A: elevation, protrusion, lateral excursion
* N: V3
Superficial head:
* O: mx tuberosity & pyramidal process of palatine bone
* I: medial surface of ramus and angle of md
* A: elevation, protrusion, lateral excursion
* N: V3
104
What is the origin, insertion, action and innervation of lateral pterygoid (upper and lower head)?
Upper
* O: infratemporal crest on greater wing of sphenoid bone
* I: articular disc and capsule of TMJ
* A: depression, protrusion, lateral excursion
* N: V3
Lower:
* O: lateral surface of lateral pterygoid plate
* I: pterygoid fovea on neck of condyle
* A: depression, protrusion, lateral excursion
* N: V3
105
What is the arterial supply and venous drainage of TMJ?
* A: external carotid (superficial temporal, maxillary)
* V: retromandibular
106
What is the sensory innervation of TMJ?
V3
107
Where is the parotid gland located?
Located posteriorly and laterally to md ramus
Makes posterior boundary of pterygomandibular space
Extends irregularly from zygomatic arch to angle of md
108
What is passage or parotid/stensons duct?
Pierces buccinator muscle and opens up in B mucosa adjacent to 2nd mx molar
109
What are boundaries of infratemporal fossa?
* Sup: infratemporal surface of greater wing of sphenoid
* Inf: where medial pterygoid attaches to md
* Lat: ramus of md, zygomatic arch
* Med: ;at pterygoid plate of sphenoid, pyramidal process of palatine bone, mx tuberosity
* Ant: posterior portion of mx
* Post: styloid process, condyles
110
Clinical sig of infratemporal space?
Infection can easily spread via infratemporal space from spaces close to oral cavity to para and retropharyngeal spaces
111
What is the importance of pterygomandibular space?
Site of IAN block. Communicates with submandibular space anteriorly and parapharyngeal space inferiorly and posteriorly
112
What are borders of pterygomandibular space?
* Med: medial pterygoid
* Lat: medial surface of ramus
* Sup: lower head of lat pterygoid
* Inf: attachment of medial pterygoid to md angle
* Post: parotid gland
* Ant: oral mucosa, post part of buccinator, pterygomandibular raphe
113
What are boundaries of oral cavity?
* Sup: hard & soft palate
* Post: palatoglossal arch
* Lat: cheeks
* Inf: soft tissues along lingual border of mandible
114
What are the contents of the pterygomandibular space?
* Branches of V3 (IAN, lingual, buccal, mylohyoid)
* Mx artery and branches (middle meningeal, pterygoid, inferior alveolar, buccal)
* Pterygoid venous plexus
* Sphenomandibular ligament
* Loose connective tissue
115
Where does the IAN run?
1. From post div of mandibular n.
2. Descends inferiorly following inferior alveolar a. & enters the mandibular foramen
116
Where does lingual nerve run?
1. From posterior division of md nerve
2. Descends close to IAN, positioned anteriorly and medially
3. Enters the FOM
4. Gives sensory innervation for anterior ⅔ of tongue, mucosa of FOM and lingual gingiva of all teeth until midline.
117
Where does buccal nerve run?
1. From anterior div of md n.
2. Passes anteriorly between 2 heads of lat pterygoid m.
3. Descends inferiorly along lower portion of temporalis
4. Appears on anterior border of ramus and masseter
118
Where does mylohyoid n. run?
1. Only motor branch from post div.
2. Branches off IAN just before it enters the mandibular foramen
3. Descends through the mylohyoid groove
4. Innervates mylohyoid m. and anterior belly of digastric m.
119
What does the pterygoid venous plexus communicate with?
* Cavernous sinus
* Pharyngeal plexus of veins
* Facial v.
120
What are the boundaries of the pterygopalatine fossa?
* Ant: infratemporal surface of mx
* Post: pterygoid process
* Med: perpendicular plate of palatine, sphenopalatine foramen
* Lat: pterygomaxillary fissue
* Sup: inferior surface of sphenoid, orbital process of palatine, inferior orbital fissure
* Inf: pyramidal process of palatine
121
What structures pass through the pterygomaxillary fissure?
* Posterior superior alveolar nerves
* 3rd part of maxillary artery
* Network of veins that drain into pterygoid plexus
122
Describe pathway of posterior superior alveolar nerves
Nerves exit through pterygomaxillary fissure from pterygopalatine fossa and enter mx via posterior superior alveolar foramina. From there, they travel though mx and reach apices of mx molars.
123
What is the passage of infraorbital nerve?
Nerve comes out of pterygopalatine fossa, onto floor of orbit via inferior orbital fissure and then travels into groove and disappears into infraorbital canal. Within canal, middle and anterior superior alveolar nerves branch off and bring innervation to anterior teeth and premolars.
124
What are the contents of pterygopalatine fossa?
* Pterygopalatine ganglion
* Mx nerve branches
* Mx artery
* Pterygoid plexus of veins
* Inferior ophthalmic vein
125
What are branches of mx nerve?
* Infraorbital n.
* Posterior superior alveolar n.
* Zygomatic n.
* Ganglionic branches (nasopalatine, greater & lesser palatine)
126
Difference between ranula and mucocele
* Ranula: swelling of **major** salivary gland duct due to trapped saliva
* Mucocele: swelling of **minor** salivary gland due to trapped saliva
127
What spaces does mandibular space infections spread to?
* Sublingual
* Buccal
* Submandibular
* Submental
128
What spaces does maxillary space infections spread to?
* Canine
* Buccal
* Infratemporal
129
Where does ludwigs angina spread to first?
Sublingual and submandibular → parapharyngeal and retropharyngeal spaces
130
Where does infection from tooth spread to first when there is cavernous sinus thrombosis?
buccal and canine
131
What are the different spaces?
* Maxillary
* Mandibular
* Buccal
* Canine
* Submental
* Sublingual
* Submandibular
* Masticator- temporal, infratemporal, pterygomandibular, submasseteric
* Pharyngeal
* Retropharyngeal
132
Where is buccal space?
Between the buccinator and masseter (contains buccal fat pad)
133
What spaces does submandibular space communicate with?
* Infratemporal
* Submental
* Sublingual
* Parapharyngeal
134
Where are the para- and retropharyngeal spaces located?
* Lateral and posterior to pharynx
* Medial to medial pterygoid m.
* Posterior to pterygomandibular raphe
* Adjacent to carotid sheath and CN IX, XI, XII
135
What is luwigs angina?
Severe potentially life-threatening cellulitis of the FOM with blockage of the airway
136
**How can Maxillary Sinusitis cause tooth pain?**
If dental branch of maxillary nerve going into maxillary molar apices, gets pressed by inflamed mucosa of infected maxillary sinus, patients can perceive it as pain coming from the tooth.
137
Describe movement of TMJ when opening mouth?
1. ROTATION in the lower compartment initiated by inf head of lat pterygoid.
2. Medial and lateral collateral ligaments tightly attach the disc to the condyle
3. Rotation continues until the upper and lower teeth are separated
4. Once the TMJ is taut, no further rotation can occur
5. TRANSLATION in the upper compartment
6. Articular disc/condyle complex slide inferiorly on the articular eminence until its lowest point
7. Suprahyoid muscles involved
138
What are the working cusps?
* Upper palatal
* Lower buccal
139
What muscles close communication between the nasopharynx and oropharynx?
* Palatopharyngeus
* Levator veli palatini
* Uvulae
140
What muscles are involved in swallowing?
* Teeth stabilised in CO by contraction of temporalis, masseter and medial pterygoid)
* Contraction of palatoglossus, styloglossus, intrinsic mm of tongue
* Oropharyngeal isthmus reduced (soft palate and pharynx come in contact)
* Epiglottis closes so food passes through oesophagus and not into the lungs
141
**What is the drainage of lymph from the left vs right hand side head and neck?**
* **RHS**: right jugular trunk joins lymphatics from right arm and thorax to form right lymphatic duct- drains at function of right internal jugular v and subclavian v.
* **LHS**: left jugular trunk and then into thoracic duct- drains at function of left internal jugular v and subclavian v.
142
What is waldeyers tonsillar ring made of?
* Pharyngeal
* Tubal
* Palatine
* Lingual
143
What are superficial lymph nodes of the head?
* Occipital
* Retroauricular
* Anterior auricular
* Superficial parotid
* Facial
144
What are deep lymph nodes of the head?
* Deep parotid
* Retropharyngeal
145
What are superficial cervical lymph nodes?
* Submental (drain md incisors)
* Submandibular (drain md and mx teeth- except md incisors and mx 3rd molars)
* External jugular
* Anterior jugular
146
What are deep cervical lymph nodes?
* Superior deep cervical group (drains mx 3rd molars)
* Inferior deep cervical group
147
What are signs and symptoms of cavernous sinus thrombosis?
* Fever
* Drowsiness
* Rapid pulse
* Diplopia
* Oedema of eyelids and conjunctiva
* Damage to CN III, IV, V1, V2, VI
148
When can cavernous sinus thrombosis be caused by dentist?
If needle pierces abscess and then pierces pterygoid plexus, infection can pass to cavernous sinus.
149
What is necrotising gingivitis?
150
What is necrotising gingivitis, what is it caused by, how does it appear and symptoms?
Microbial disease of the gingiva with impaired host response (poor nutrition, inadequate rest, tobacco, stress). It is characterized by:
* Punched out craters of interdental papillae
* Gingival craters covered by gray, pseudomembranous slough
* Fetid odour, spontaneous bleeding, increased salivation
* Sensitive to touch
* Metallic, foul taste
* Constant radiating gnawing pain (intensified by spicy, hot foods)
When bone loss occurs, it becomes necrotising periodontitis.
151
How is NG managed?
* Gentle removal of plaque/necrotic debris with hand instruments (use LA if required)
* Local irrigation with CHX 0.2% or hydrogen peroxide 3%
* Antibiotic therapy (metronidazole)
* Analgesics
* Stop smoking
* Review pt in 48-72 hours, perform perio exam and OHI, thorough debridement
* If not responsive beyond 2 weeks, refer to specialist
152
What are the clinical features of herpetic gingivostomatitis?
* After 24 hours, gray vesicles rupture and form painful, small ulcers with red elevated margins and yellow centre
* Diffuse, erythematous, shiny gingiva and oral mucosa with edema and bleeding.
* Lasts 7-10 days
* Pain, difficulty eating, brushing
* High fever, cervical adenitis, generalised malaise
153
What is the management for herpetic gingivostomatitis?
* Antipyretics
* Antiviral meds
* Staying hydrated
154
What is pericorontitis and symptoms?
Inflammation of gingiva in relation to crown of an incompletely erupted tooth. Space between crown and operculum accumulates food debris and bacteria.
* Red, swollen, suppurating lesion
* Radiating pain to ear, throat and FOM
* Foul taste
* Trismus
155
Difference between pericoronitis and pericoronal abscess
Pericoronitis is inflammation of operculum.
Pericoronal abscess is collection of pus.
156
What is the management of pericoronitis?
* Operculectomy (tissue will likely regrow)
* Exo of tooth
157
What is a gingival abscess?
* Localised, purulent infecting involving marginal gingiva or interdental papilla.
* Hx of trauma or food lodgement
* Rarely painful
158
What is a periodontal abscess?
* A localized purulent infection within the tissue adjacent to a perio pocket that may lead to the destruction of PDL and alveolar bone.
* Vital tooth
* Painful at times
* Pus discharge via pocket or sinus opening
159
How is periodontal abscess managed?
* Drain through sulcus with probe or scaling of tooth surface
* Irrigation with saline
* Removal of foreign bodies
* Compression and debridement of soft tissue wall
* OHI
* Antibiotics only if systemic symptoms exist
160
What is stage I periodontitis?
* 1-2mm CAL
* \< 15% BL around root
* No tooth loss due to perio
* PD _\<_4mm
161
What is stage II periodontitis?
* 3-4mm CAL
* 15-33% BL
* No tooth loss
* PD _\<_5mm
162
What is stage III periodontitis?
* BL: \>33% of root
* Lost _\<_4 teeth due to perio
* PD _\>_6mm
* Class II or III furcation lesions
* Vertical BL: _\>_3mm
163
What is stage IV periodontitis?
* All stage III features
* Complex rehab required
164
What is the difference between grade A, B and C
% BL/Age
* A: \<0.5
* B: 0.5-1
* C: \>1
165
What are stages 1-4 periodontitis?
* I: BL \<15% (\<2mm)
* II: BL coronal ⅓ of root
* III: Mid ⅓ of root
* IV: Apical ⅓ of root
166
Why are antibiotics sometimes not effective against abscesses?
Fibroblasts may enter the area and end up “walling off” the infection/inflammation to prevent spreading. Antibiotics may not be able to penetrate the abscess – instead treatment relies on surgical incision / drainage.
167
What antibiotics can be given for unresponsive infections?
* Metronidazole + amoxicillin
OR
* Co-amoxyclav
168
What infection can broad spectrum antibiotics cause?
Clostridium difficile
169
What is co-amoxiclav used for?
Used when beta-lactamase producing bacteria are resistant to amoxicillin. Can be used to treat severe dental infections with spreading cellulitis or dental infection that is unresponsive to 1st line antibacterial tx.
170
What procedures warrant AB prophylaxis in high risk patients?
* Exo
* Perio procedures- surgery, subgingival scaling and root planing
* Full mouth perio probing
171
What drugs do antibiotics interact with?
Warfarin (increased effect)
Oral contraceptive (less effective)
172
What are dental effects of tetracyclines?
Tetracyclines bind to Ca2+ and become deposited in bones and teeth. It can cause dental staining, enamel hypoplasia.
AVOID during pregnancy, breastfeeding and in young children
173
What are drug interactions with St John's Wort?
Avoid tramadol
Causes inc metabolism of benzos,
174
What meds can trigger asthmatic attack?
* Aspirin, NSAIDs
* Opioids
* Sulphite-containing LA
175
When are NOAC levels at their peak?
1-4 hours after taking NOAC (avoid exo at this time)
176
What is minimal alveolar concentration (MAC)?
Min concentration required to abolish response to surgical incision in 50% of patients (lower MAC, more potent anaesthetic)
177
How does pH of tissues affect LA?
Inflamed tissues are often more acidic than normal body pH due to hypoxia- therefore more resistant to effects of LA. Less LA getting into nerves and less blocking effect.
178
What is molarisation?
When an incisor, canine or premolar develops molar characteristics (i.e. 3 roots)
179
Describe curvature of upper first molars
* MB root: curved toward D
* DB root: usually straight
* P root: curved toward B
180
What are C-shaped canals?
* When roots are compressed during development they can
merge into each other and root canals can as well. Root canals
can develop in C shaped structure.
* Rare
* Most common in lower molars and premolars
* Send to specialist
181
What are COX-2 selective agents?
Celecoxib is a highly selective NSAID. There is reduced incidence of GI bleeding and ulceration.
182
When should paracetamol be used instead of ibuprofen?
* Allergy
* Haemophilia
* Peptic ulcers
* Asthmatics
* Liver or renal disease
* Heart failure
* Pregnant
183
What drugs can asthmatics have/not have?
Can have: paracetemol, oxycodone
Can't have: morphine, codeine, ibuprofen
184
What is the size of one dentinal tubule and bacteria?
Dentinal tubule: 1-2um
Bacteria: 0.1um (5-20 fit in one tubule)
185
What cytokines activate osteoclastic bone resorption in periapical periodontitis?
IL1β and TNFβ
186
What is the issue with dressing root canal with ledermix and odontopaste?
Shouldn't be used longer than 7 days as it can lead to:
* Discolouration
* Selection of fungi
* Risk of flare up
Follow up with Ca(OH)2 for at least 1 week
187
What is secondary vs tertiary dentine?
* Secondary dentin: layer of dentin produced after the tooth's root is completely formed.
* Tertiary dentin: created in response to a stimulus e.g decay or wear.
188
What is the reaction of pulp-dentine complex to bacterial stimuli?
* Sclerosis of dentine tubules
* Apposition of reactionary dentine
* Activation of A-delta and C-fibres (pain)
* Growth of pulpal cells
189
What material can be used for pulp capping? How does it work?
* Ca(OH)2
* MTA
* Biodentine
Capping material produces local necrosis and stimulates formation of tertiary dentine
190
What is the length, # roots and # root canals for maxillary central and lateral incisors?
* Length: 22.5mm
* Roots: 1
* Root canals: 1
191
What is the length, # roots and # root canals for maxillary canines?
* Length: 26mm
* Roots: 1
* Root canals: 1
192
What is the length, # roots and # root canals for maxillary 1st premolars?
* Length: 21mm
* Roots: 2 (80%)
* Root canals: 2 (95%)
193
What is the length, # roots and # root canals for maxillary 2nd premolars?
* Length: 22mm
* Roots: 1 (90%)
* Root canals: 1 (74%)
194
What is the length, # roots and # root canals for maxillary 1st molars?
* Length: 21mm
* Roots: 3 (85%), 2 (15%)
* Root canals: 4 (60%) or 3 (40%)
4th canal is MB2
195
What is the length, # roots and # root canals for maxillary 2nd molars?
* Length: 20mm
* Roots: 3 (80%), 2 (19%)
* Root canals: 3 (57%), 4 (40%)
196
What is the length, # roots and # root canals for mandibular central and lateral incisors?
* Length: 21mm
* Roots: 1
* Root canals: 1 (60%), 2 (40%)
197
What is the length, # roots and # root canals for mandibular canines?
* Length: 26mm
* Roots: 1 (98%)
* Root canals: 1 (94%)
198
What is the length, # roots and # root canals for mandibular 1st premolars?
* Length: 22mm
* Roots: 1
* Root canals: 1 (75%), 2 (20%), 3 (5%)
199
What is the length, # roots and # root canals for mandibular 2nd premolars?
* Length: 22mm
* Roots: 1
* Root canals: 1 (75%), 2 (20%), 3 (5%)
200
What is the length, # roots and # root canals for mandibular 1st molars?
* Length: 21mm
* Roots: 2 (98%), 3 (2%)
* Root canals: 3 (80%), 2 (13%), 4 (7%)
201
What is the length, # roots and # root canals for mandibular 2nd molars?
* Length: 20mm
* Roots: 2 (84%), 1 (15%)
* Canals: 3 (77%), 2 (13%)
202
What are oral implications of dry mouth?
* Dry mucosa, red, atrophic
* Depapillated and lobulated tongue
* Parotid swelling 30% of cases
* Discomfort with speech, eating, swallowing, disturbed taste, predisposition to infection; candida, salivary gland infection, caries, halitosis
203
What “thing” most likely ↓ dentin bonding – name this molecule and way to prevent this.
Matrix metalloproteinases- degrades the collagen matrix leading to a weaker bond
204
What is cavernous sinus thrombosis?
* Valveless veins allows easy backward spread of infection to cavernous sinus- Through superior and inferior ophthalmic veins and deep facial vein through pterygoid plexus
* Symptoms: decrease or loss of vision, exophthalmos, sharp headache and paralysis of the cranial nerves that travels through the cavernous sinus, confusion
* Urgent and life-threatening
* ED for iv antibiotics +/- surgery under GA
