Why do you need a surgical plan?
...
What are the components of a surgical plan?
...
What different suture materials may be used in dento-alveolar surgery?
...
What are the six steps of surgical exo?
Flap design, bone removal, tooth division, tooth removal, wound cleaning, primary closure.
What are the layers of a flap used in oral surgery?
mucosa and periosteum
How should a flap incision be made?
One continuous stroke through to bone at right angles to the mucosa.
Which part of the flap should be widest? Why?
The base so blood supply to the flap is maintained.
Should the papilla be included in a flap? Why?
Yes to avoid poor gingival contours.
What must be beneath the margins of the flap to minimise the risk of wound dehisence?
Sound bone
What are three objectives of removing bone?
Allow application of forceps/elevators
Allow exposure for tooth sectioning
Provide pathway for tooth removal
What is used to remove bone? What is the problem with high speed air turbines for bone removal?
Chisel or powered handpieces with water cooling and exhaust away from the surgical site.
High speed air turbines may produce surgical wound emphysema and dont allow tactile discrimination between bone and tooth.
What two tools may be used to section a tooth? What will give the most predictable result?
Osteotome or powered handpiece may be used. Handpiece will produce a more predictable result.
What must be done to the wound site following extraction?
Debridement and irrigation.
If debridement and irrigation is not performed what may be left behind in the socket?
Remnant of the dental follicle, periapical pathology, tooth or bone fragments, sharp bone edges, microscopic debris.
What is another name for figure-of-eight suture?
Haemorrhagic suture
What are some desired qualities of suture material?
Maintain tensile strength until wound wont separate, adequate handling characteristics and knot security, no inflammatory response, sterilisable, not conducive to bacterial growth
What is the difference between plain and chromic gut in terms of material properties?
Plain is absorbed in 3-10 days whereas chromic is absorbed in 10-20 days
How is gut, vicryl, silk and nylon absorbed?
Gut by proteolytic enzymes, vicryl by hydrolysis, silk and nylon by encapsulation by fibrous connective tissue.
What is vicryl made from and what is it's absorption rate?
A polymer of glycolic and lactic acid (polyglactin). Holds tensile strength for >2 weeks, completely absorbed in 56-70 days.
Does silk induce an inflammatory response?
Induces an acute inflammatory response.
What is the inflammatory response to vicryl, nylon and prolene?
Minimal
What is the absorption of prolene?
It is non-absorbable
What is the inflammatory response to gut?
Moderate
What are the indications for silk suture material?
CVS, ophthalmic and neuro surgery
What are the 7 steps to a surgical plan?
1. Approach - design of flap
2. Delivery method of tooth
3. Forceps/elevators/sectioning
4. Bone removal
5. Closure and suture material
6. Analgesic/antibiotics
7. Review
How is the flap reflected from bone?
With a periosteal elevator
What are some factors that predispose a tooth to fracture during exo?
History of difficult exos, heavily restored, deep caries, complex roots, hypercementosis/ankylosis, clumsy use of force
What are the indications for removal of a retained or fractured root?
non-vital root, periapical pathology, likelihood of exposure with progression of bone resorption, planned ortho or fixed pros
In an edentulous ridge where is the safest place to place an incision?
Along the crest of the alveolar ridge
What are some causes of maxillary canine impaction?
nonresorption of primary canines, ankylosis of impacted canines, contracted maxillary arch, absence of lateral incisor to guide eruption, pathology in path of eruption (supernumery, cyst), trauma damaging tooth germ.
What are some sequelae of having impacted maxillary canines?
Resorption of adjacent lateral incisor roots
Dentigerous cyst formation
Infection if there is a communication with the oral cavity
What are some treatment options for an impacted maxillary canine?
Leave
Extract
Surgical exposure and ortho
Transplantation
What approach is used for 80% of impacted canines?
Palatal approach
What are some potential complications of impacted maxillary incisor surgery?
Damage to adjacent teeth
Haematoma under the flap
Necrosis of flap
Perforation into nasal cavity or maxillary sinus
True or false. You should only ever incise the gingival margin of the tooth being extracted and not the adjacent tooth/teeth.
True
What should and should not be under the flap margins?
sound bone and not the surgical defect
Is a maxillary impacted canine removed whole?
No. Section it and remove crown and root separately.
Do retained vital roots need to be removed?
Not necessarily
Can you rest an elevator on the tooth adjacent to that being extracted?
No. Only rest it on the to be extracted tooth
What are some indications for surgical extraction?
Divergent/curved roots
Decoronated teeth
RCT teeth
Dense sclerotic bone or thick buccal plate
Root abnormalities (caries, bulbous, long, hypercementosis, anklosed)
Pneumatized antrum
Lone standing maxillary molar
If the patient is a bruxer
What are some contraindications for surgical extraction?
Acute systemic infection
Bleeding disorder
Undiagnosed pathology in the area
Immunosuppression
What are some indications for third molar extraction?
Recurrent pericoronitis (3 episodes or more)
Retention with cyst formation
Partially erupted teeth can harbour pathogenic microflora
Carious
Perio pocket of adjacent 7
At what age do most extraction complications occur?
In those over 40 years
When woud you chose to refer a surgical extraction?
Lacking experience
If going to take longer than 30-40 mins
If patient refuses LA
Complex
If MH indicates either previous radiotherapy, high dose bisphosphonates, or immunocompromise
What is the maximum INR value that may be considered ok for MOS?
INR must be less than 4.
How should patients that are on warfarin therapy be managed in MOS?
INR must be checked within 24 hours of surgery and it must be less than 4. A haemostatic agent such as oxidised cellulose should be sutured into the extraction socket.
When do you raise a flap?
Fractured tooth
Impacted or unerupted teeth
Apicetomy
Cyst removal
Repair of facial fractures
What are 3 different types of flaps?
Envelope
2 sided
3 sided
How many incisions are required for an envelope flap and where is it/they made?
One incision along the gingival margin/alveolar crest
How do you cut a 2 sided flap?
Envelope flap + relieving incision
How far apical should flaps be made?
To the apex of the tooth root
What is the most common suture material used in the clinic?
3/0 chromic gut
When would you use silk as a suture material?
Closure of oroantral fistula.
What pain meds can be taken post op and at what does?
Ibuprofen 400mg tds
Paracetamol 500mg-1g qds
Codeine may be combined with paracetamol if severe pain
When are post op Abs indicated?
Immunocompromise
Exposed sinus
Significant preop infection
What post op ABs may be prescribed?
Depends on the anticipated pathogen.
Amoxicillin 250mg tds 5-7 days
Metronidazole 200mg tds 5 days
Chlorhex mouthwash
What are Winter's lines and what do they represent?
White line - occlusal plane of 6 and 7 used to assess angulation of 8.
Amber line - follows the CEJ of the 6 and 7 then follows the external oblique ridge, represents the bone level.
Red line - a line drawn perpendicular to the amber line down to where yo
What constitutes a difficult extraction according to Winter's lines?
A red line of more than 5mm. For every one mm longer it becomes three times as hard.
Are distoangular or mesioangular impacted 8's more difficult to extract?
Distoangular
What does WHARFE stand for in relation to assessing the difficulty of an extraction?
Winter's lines - mesio/vertical/distoangular
Height of bone that needs to be removed
Angulation of second molar
Root morphology
Follicle size
Exit path
How would you section and remove a two rooted distoangular impacted 8?
Section the tooth vertically and remove the distal root first. Then remove the mesial root.
What are the contents of the cavernous sinus?
Internal carotid artery
CNs III, IV, VI, V1, V2
Infections from what location may lead to cavernous sinus thrombosis?
Any maxillary, nasal or orbital source, particularly structures in the dangerous triangle.
How may someone with cavenrous sinus thrombosis present clinically?
Exophthalmos, orbital oedema, lateral gaze palsy (CN VI), mydriasis, ptosis (CN III), hyperaesthesia of V1/V2 dermatomes, sharp headache, visual disturbance, mental status changes, death
Infection spread from retro-molar regions (mandibular molars) may spread to which spaces?
Buccal
Sub-masseteric (between masseter and mandible)
Pterygomandibular (between mandible and medial pterygoid)
Lateral pharyngeal (between superior constrictor and medial pterygoid)
Sublingual
Submandibular
Vestibule
What tissue spaces are infected with Ludwig's angina?
May involve sub-lingual, submandibular and submental spaces.
What is the dominant symptom of sub-masseteric/pterygomandibular infection?
Severe trismus often without extra-oral swelling
What are the signs and symptoms of lateral pharyngeal infection?
Pain on swallowing, trismus, systemically unwell. Tonsil and pharyngeal wall displaced, uvula deflected, neck swelling, dysphagia, drooling
What are some sequelae to lateral pharyngeal infection?
Thrombosis of internal jugular, erosion of arteries
CN IX-XII damage
Spread to retropharyngeal space -> mediastinum
List the contents of the submandibular space
Fat
SM gland
SM LNs
What are the boundaries of the submandibular space?
Roof: mylohyoid and mandible
Medially: anterior belly of digastric
Laterally: skin
Inferiorly: hyoid bone
Posteriorly: posterior belly of digastric
What are the contents of the sublingual space?
Sublingual gland
LNs
Vessels
Fat
What are the boundaries of the sublingual space?
Roof: floor of mouth
Floor: mylohoid muscle
Lateral: mandible and mylohyoid
Medial: genioglossus
What are the contents of the submental space?
Mylohoid muscle
Fat
Blood vessels
LNs
What are the boundaries of the submental space?
Lateral: anterior belly of digastric
Medial: midline
Inferior: hyoid
Apart from odontogenic infection what are some other causes of Ludwig's angina?
Tonsillitis
Sialadenitis
Epiglottitis
Infected thyroglossal cyst
Infected compound fractured mandible
Penetrating injury to floor of the mouth
Trauma from intubation
What is the management for Ludwig's angina?
Establish patent airway (awake, dont use laryngoscope or spasm will occur). Do this with patient sitting up.
Medications: steroids, IV ABs (metronidazole, clindamycin, penicillin combination adjusted with CST results.
Surgical drainage of submandibular an
What is the management of cavernous sinus thrombosis?
ABs 3-4 weeks
Heparin
Corticosteroids
Surgical drainage of infection
What are some complications of cavernous sinus thrombosis?
Meningitis
Septic emboli
Blindness
Cranial nerve palsy
Sepsis and shock
Death
How may a patient with anaphylaxis present?
Urticaria
Angioedema
Hypotension
Bronchospasm
What are the steps to follow for any medical emergency?
Stop the procedure
Observe airway, breathingm circulation and neurological state
Call for help
Appropriate meds
CPR
What are the signs and symptoms of diabetic ketoacidosis?
Vomiting, headache, PU/PD, abdominal pain, drowsiness, hyperventilation. Usually in type 1 DM.
What dose of adrenalin should be administered for anaphylaxis?
0.3-0.5mg for IM injection. Epi pen has 0.3mg
What type of drug is salbutamol and what is it used for?
beta-2 agonist used for bronchospasm
What does of hydrocortisone should be administered for adrenal crisis?
100mg
How long should you wait post-full clearance before taking a denture impression?
6 weeks
How many minutes should you scrub for, for the first scrub of the day?
5 minutes
How many minutes should you scrub for in between patients?
3 minutes
How should you pass another surgeon in the theatre away from the surgical field?
Front to front
How should you pass another surgeon next to the sterile field?
Back to back
What are Mitchell trimmers used for in oral surgery?
Aid in mucoperiosteal flap elevation
What should be included on a prescription?
Patient name and address
Prescribers name, address, telephone number
Generic drug name and form
Drug dose and frequency
Quantity of drug
Signature of prescriber and date
Prescriber number, if item is included in PBS
Example script
John Smith, 123 Fake Street
Dr Steven Lee, 1 Sydney Street, 92123123
Amoxicillin 250mg tablets
Take one tablet three times daily for 5 days
15 tablets
Signature, 01/01/2014
13020
What patients require prophylactic ABs if undergoing an invasive dental treatment?
Endocarditis:
prosthetic valves
previous endocarditis
heart transplant with valvulopathy
rheumatic heart disease in Indigenous
congenital heart disease if it involves unrepaired cyanotic defects, for the first 6 months following repair of defect with pros
What is the recommended regimen for patients requiring antimicrobial prophylaxis?
2g amoxicillin one hour before treatment. If allergic or been on it for a long time in the past then cephalexin 2g OR clindamycin 600mg one hour prior.
What are some clinical signs or symptoms that may indicate antimicrobials are indicated?
Lymphadenitis, trismus, dysphagia, toxaemia, imuunocomprimised, swelling
What is the dose for amoxicillin?
250-500mg tds
What is the dose rate for Augmentin Duo Forte (amoxicillin clavulanic acid) and what organisms does it provide protection against?
875mg bd
Staph. aureus
What is the dose for cefalexin?
250-500mg qds
What is the dose for erythromycin?
250-500mg qds
What is the dose rate for clindamycin?
150-300mg qds
What is the dose rate for metronidazol?
200-400mg tds
How does warfarin work?
Vit K antagonist
How do aspirin/dipyridamole/ticlopidine/clopidogrel work?
Inhibits platelet aggregation
How does alteplase work?
Tissue plasminogen activator. Opposite to tranexamic acid.
What cant be taken with metronidazole?
alcohol (disulfiram like effects) warfarin (inhibition of cytochrome P2C9, potentiating warfarin)
What drugs may induce gingival hypertrophy?
Ca channel blockers, phenytoin, cyclosporin
Name four contraindications for NSAIDs.
Dont use with corticosteroids, asthma, peptic ulcer or bleeding tendency
Discuss the adverse effects of AB prescription.
Resistance
Drug interactions (metronidazole and alcohol, amoxicillin and warfarin)
Clostridium difficile overgrowth -> ulcerative colitis (clindamycin, amoxicillin, cephalexin)
Allergy
Cost
What may occur if a mucosal flap does not include the underlying periosteum?
There will be significant post-op swelling because the plane under the mucosa is vascular.
Give the prescription directions for amoxicillin.
Amoxicillin 500mg capsules
1 capsule tds for 7 days
Give the prescription directions for metronidazole.
Metronidazol 200mg tablets
1 tablet tds for 7 days
Give the prescription directions for clindamycin
Clindamycin 150mg capsules
1 capsule qid for 5 days
Give the prescription directions for Panadeine forte
Panadeine forte tablets
1 tablet every 4 hours prn or for severe pain 2 tablets prn.
Give the prescription directions for ibuprofen
Ibuprofen 400mg tablets
1 tablet qid for 5 days
List come conditions that may compromise host defences.
Diabetes
Alcoholism
Malnutrition
Leukaemia
Lymphoma
Malignancy
Chemotherapy
Immunosuppressives
What are some causes of collapse in a patient?
Vasovagal syncope
Hypoglycaemia
Myocardial infarction
Stroke
Seizure
How does nitrous oxide work?
Unknown but may involve blocking NMDA channels
Endocrine Disorders
Know acromegaly, Cushing's disease, Addison's, systemic steroid therapy patients, Grave's, hyperparathyroidism, diabetes mellitus
What hormones are released from the pituitary?
ACTH (stimulates cortisol release)
GH
MSH
TSH
FSH, LH
Prolactin
Oxytocin
ADH
Describe the hypothalamus-pituitary-adrenal axis
Corticotropin releasing hormone is released from the hypothalamus
This stimulates adrenocorticotropic hormone release from the anterior pituitary
ACTH stimulates the release of cortisol from the adrenal cortex
What else is produced by the adrenal cortex?
Cortisol (glucocorticoids)
Aldosterone (mineralocorticoids)
Androgens
What are some clinical consequences of having a pituitary gland tumour?
May encroach on neighboring structures such as the optic nerve - visual defects
May produce excess hormones such as GH (acromegaly), ACTH (Cushing's disease), TSH (hyperthyroidism)
What is the cause of 95% of acromegaly cases?
Pituitary adenoma producing excess GH
What are the clinical manifestations of acromegaly?
Excessive growth of the angle of the mandible
Large hands and feet
Ill fitting dentures
Spaced teeth
Impaired vision
Fatigue
DM
Hypertension
What is the cause of 70% of Cushing's disease patients?
Pituitary tumour producing ACTH
May also occur with excess CRH from the hypothalamus
What are the clinical features of Cushing's disease?
Moon face, buffalo hump, central obesity
Delayed wound healing
Osteoporosis
Hirsutism
DM
Hypertension
How is Cushings syndrome different to Cushing's disease?
Cushing's syndrome describes the signs and symptoms associated with prolonged exposure to high levels of cortisol. This may be caused by Cushing's disease or exogenous glucocorticoid intake.
What is the cause of most cases of primary Addison's disease?
Autoimmune destruction of the adrenal cortex
May also occur due to infection (TB) and metastases
What is the cause of secondary Addison's disease?
High dose exogenous steroid intake for longer than one week results in decreased ACTH secretion (and CRH) causing adrenocortical atrophy
What are the clinical features of Addison's disease?
Weight loss, dehydration, wasting, anorexia, malaise, postural hypotension, hyperpigmentation (only in primary form as ACTH is produced with MSH), salt craving
What is normal physiological cortisol production?
30mg
What dose of systemic corticosteroid can be sufficient to cause adrenal suppression?
Prednisone greater than 10mg/day for longer than 3 weeks
What are the signs of Addisonian crisis?
Hypotension, vomiting, diarrhoea, confusion, LOC, coma, death
What is the function of cortisol?
Stimulates gluconeogenesis
Sensitises the vasculature to adrenalin and noradrenalin
Anti-inflammatory
What are the guidelines on steroid cover for patients with adrenal suppression or insufficiency?
If it is a stressful procedure lasting longer than 1 hour - double dose that day
If it is a GA surgical procedure - 100-150mg hyrdrocortisone that day tapering back to normal replacement dose over the next few days
What is the relative potency of cortisol, pred and dex?
cortisol < pred < dexamethasone
What is Grave's disease?
Autoimmune disease where autoantibodies are produced to the TSH receptor resulting in hyperthyroidism
What are the clinical features of Grave's disease?
Anxiety, tachycardia, palpitations
Heat intolerance
Weight loss
Muscle weakness
Hair loss
Exopthalmos
What causes primary and secondary hyperparathyroidism?
Primary - adenoma of the parathyroid gland
Secondary - renal failure (calcium loss vie urine)
What are some features of hyperparathyroidism?
Brown tumours of the jaws
What are the radiological features of brown tumours?
Well-defined radiolucent areas
Loss of LD
Ground glass appearance replacing normal trabecular pattern
Bone expansion
Describe the histology of brown tumours
Multinucleated giant cells
Abundant stroma consisting of bundles of spindle or oval cells
What are the ddx for brown tumours
Cherubism
Fibrous dysplasia
ABC
What causes diabetes?
Autoimmune destruction of the pancreatic beta cells
What is normal BSL?
3.5-7 mM/L if fasting otherwise <11 mM/L
What is considered poorly controlled BSL?
>16mM/L
What precautions can be taken for poorly controlled diabetics?
Delay procedure and ask them to visit their GP
Antibiotic prophylaxis administered before treatment
Swab and MC&S
What are the effects of hyperglycaemia?
Redcues phagocytic function
Vascular wall changes - reduced blood flow and transport of granulocytes ot injury site
Xerostomia (osmotic diuresis)
Gingivitis, perio abscesses, periodontitis, lichenoid reactions, candidiasis, sialadenosis
What are the signs and symptoms of hypoglycaemia?
Sweaty, tachycardia/palpitations, anxiety, dilated pupils, pins and needles, pallor
Headache, confusion, slurred speech, ataxia, amnesia
Missed meal although taken insulin
What is the treatment for hypoglycaemia?
Give 20 grams of glucose drink
DRSABCD if unconscious
What are the long term effects of diabetes mellitus?
Accelerated atherosclerosis
Retinopathy and cataracts
Peripheral neuropathy
Autonomic neuropathy
Nephropathy
Trauma
...
What two radiographs do you need for any suspected mandibular fracture?
OPG
PA mandible
Could also do a CT for better resolution and 3D image, a lateral oblique of the mandible, and a chest xray to rule out aspiration of teeth
What are the indications for taking a reverse Towne's radiograph?
To assess potential fracture of the condylar neck
What are the indications for taking a Water's radiograph?
Examination of frontal and maxillary sinuses, orbit and nasal fossa
What is another name for the Water's radiograph?
Occipeto-menton radiograph (beam passes through occipital bone and menton)
What is the positioning for Waters view?
Head tilted up by around 30 degrees with chin on film
What is the positioning for reverses Townes view?
Head tilted down, jaw open and forehead on film
What is the positioning for a PA mandible?
Forehead and nose against film with Frankfurt plane at 90 degrees to it.
Mouth open as wide as possible
What things should be assessed on the primary survey following maxillofacial trauma?
Airway - loose teeth, blood, grossly displaced fractures obstructing airway, may require intubation at this stage
Breathing
Circulation
Neurological evaluation - GCS, cranial nerves, general
Control the cervical spine
What are some serious injuries to be aware of following trauma?
Fractured cribriform plate - CSF rhinorrhoea
Central respiratory failure
Obstructed airway - blood, vomit, saliva, bone, teeth, denture
Fractured thorax or sternum
Pneumothorax
Ruptured liver or spleen
What are some measures to arrest haemorrhage?
Pressure or clamping of bleeding vessels
Placement of oro-nasal packs
Temporary stabilisation of bony fractures (eg wire around teeth)
Ligation of vessels
Angiography with therapeutic embolisation
What simple piece of equipment can be used to control epistaxis?
Post nasal pack with a foley catheter
What injuries are all patients with maxillofacial trauma assumed to have until proven otherwise?
Head and neck injuries
What are some signs and symptoms of maxillofacial trauma?
Pain, swelling, bruising, haematoma, facial deformity ro malfunction, rhinorrhoea, otorrhea
Give an example of indirect trauma causing fracture.
A blow to the mandibular symphysis can cause a distant subcondylar fracture.
What diagnostic information should be collected from the maxilofacial trauma patient
Any changes in the way the teeth meet?
Pain and pain history if present
Any numbness to skin, teeth or mucosa?
Alterations in speaking, chewing, swallowing, opening the mouth
Hearing/vision disturbances
Abnormal sounds from jaw joints
Neck problems
What variables are measured by the Glasgow Coma Scale?
Eye opening (spontaneous, to speech, to pain, never)
Motor response (obeys commands, localises pain, flexion withdrawal, decerebrate flexion, decerebrate extension, no response)
Verbal response (orientated, confused, inapproprite words, sounds, silent)
What score on the GCS indicates coma?
<8/15
How would you check clinically for a Le Fort fracture?
Place patient's head against head rest, grasping the upper teeth and alveolus move them gently.
Describe Le Fort 1 fracture pattern
Horizontal maxillary fracture immediately above the teeth and palate
Describe Le Fort 2 fracture pattern
Pyramidal fracture extending from zygomatic butresses through the infraorbital margins to the bridge of the nose
Describe Le Fort 3 fracture pattern
Detachment of the facial bones, including the zygomas, from the skull base. Fractures through the zygomatic arch, the frontal process of the zygomer and the bridge of the nose.
What is the benefit of operating on a facial trauma case 5-7 days following the accident?
After this time swelling will be less, there may be resolution of brain injury and other systemic trauma, resolution of alcohol/drug intoxication
When is immediate surgery indicated following maxillofacial trauma?
Haemorrhage, when other injuries need immediate operating.
When is surgery indicated for Le Fort fractures?
Asymmetry, displacement, comminuted fracture, sustained occlusal derangement
What treatment options are available for maxillofacial fractures?
Closed reduction
Open reduction with internal fixation (ORIF)
External fixation
What are some possible injuries following upper facial 1/3 high energy impact?
Intracranial injury
Frontal sinus fractures
Dural tears
Nasofrontal duct disruption
What are the signs and symptoms of frontal bone fracture?
Disruption or crepitus of the supraorbital rims
Subcutaneous emphysema
Paraestheisa of the supraorbital and supratrochlea nerves
Pain and oedema
Deformity
What is the most common fracture to the middle third of the face?
Nasal fracture due to its protruded position and lack of support
What are the signs and symptoms of nasal bone fracture?
Epistaxis, deformity, crepitus, periorbital ecchymosis, nasal obstruction, tenderness and swelling, septal haematoma
How are nasal bone fractures usually managed?
Closed reduction under LA or GA
What is the second most common fracture to the middle third of the face?
Zygomaticomaxillary complex fractures (cheeck bone)
What are some signs and symptoms of zygomaticomaxillary fracture?
Pain and oedema
Ecchymosis of the cheek and eyelids
Malar flattening
Periorbital step deformity
Trismus (coronoid next to zygomatic arch)
Subcutaneous emphysema
Infra-orbital nerve paraesthesia
Diplopia, hypophthalmos (displacement of the globe inferiorly
Following zygomaticomaxillary complex fracture, referral to which medical specialty is essential?
Ophthalmologist
A blow low on on the maxillary alveolar rim will result in what type of Le Fort fracture?
Le Fort I
A blow to the lower of middle maxill may result in what type of Le Fort fracture?
Le Fort II
What bones are fracture in Le Fort II fracture?
Maxilla, zygomatic bones, nasal bones
A blow to the upper maxilla may result in what type of Le Fort fracture?
Le Fort III
What bones are fractured with a Le Fort III fracture?
Zygomatic bone/temporal bone, zygomatic/frontal bone, nasal bones, bones of the orbit
What are the six sites of mandibular fracture in order of frequency?
1. Condylar process (30%)
2. Body (25%)
3. Angle (25%)
4. Symphasis/parasympasis (15%)
5. Ramus (3%)
6.Coronoid (2%)
*In children the parasymphaseal region is most commonly involved due to the unerupted canine
What are the signs and symptoms of mandibular fracture?
Malocclusion
Paraesthesia of lower lip/chin
Limited movement of mandible
Deviation of the mandible to the side of the fracture
Crepitus
Tooth mobility
Pain, swelling, ecchymosis
What is a panfacial fracture?
Fractures to the upper, middle and lower face following high energy impact
What are some complications following facial trauma?
Aspiration
Airway compromise
Haemorrhage
Facial deformity
Nerve damage
Scarring
Chronic sinusitis
Infection
Weight loss
Malunion of fractures
Malocclusion
Malnutrition
What are some examples of maxillofacial fractures that don't require surgical intervention?
Undisplaced stable fractures
Some displaced condylar fractures where the occlusion is not deranged.
What is intermaxillary fixation used for?
Stabilizing broken maxillofacial bones allowing them to heal together with correct MMR.
Management of oral malignant and premalignant lesions
...
What are the signs of nicotinic stomatitis?
White palatal proliferations with central red areas
Red areas are inflamed minor salivary gland ducts
Surrounding mucosa often white
Most common in cigar and pipe smokers
What are the histological features of nicotinic keratosis?
Hyerpkeratosis, acanthosis
Ductal inflammation
No dysplasia
What is the management and prognosis for nicotinic stomatitis?
No progression of dysplasia (ie not premalignant)
Reversible following smoking cessation
What are the clinical features of lichen planus?
Bilateral
Buccal mucosa, tongue, attached gingiva
Reticula striae
Lesions persist for years with exacerbations and quinescence
Name the 6 forms of lichen planus
Reticular
Erosive
Papular
Plaque
Atrophic
Bullous
List some premalignant conditions
Definitely premalignant:
Leuko/erythroplakia
Chronic hyperplastic candidiasis
Associated with oral cancer:
Oral submucous fibrosis
Plummer-Vinson syndrome
Syphillus glossitis
Possible:
Atrophic and erosive forms of lichen planus
DLE
What lesion most commonly shows more dysplasia, leukoplakia or erythroplakia?
Erythroplakia
What are the risk factors for oral SCC?
Smoking (cigs, cigars, pipe)
Alcohol (not as strong as tobacco)
UV light
Nutritional deficiencies of iron (Plummer-Vinson) and possibly vitamins ABCE
What is Plummer-Vinson syndrome and how is it managed?
Aka siderpenic dysphagia, Paterson-Kelly syndrome
Most commonly in post menpausal women
Presents with dysphagia, oesophageal webs and iron deficiency anaemia
Symptoms incude dysphagia, burning mouth, atrophic glossitis
Managed with iron supplementation an
What viruses play a role in development of SCC?
HPV and HSV may have a synergistic effect
What is the 5 year survival for stage I SCC?
85%
What is the five year survival for stage IV SCC?
10%
What are two histological predictors of prognosis for oral SCC?
Invasion pattern and depth
What are the most common primary tumours to metastasise to the oral cavity?
Lung and breast cancer
Where do intra-oral melanomas usually present?
Hard palate, alveolar mucosa, gingiva
What is the average survival time for malignant melanoma?
2 years
What malignancies does HIV predispose to?
HIV predisposes to lymphoma and Kaposi's sarcoma
What are three forms of lymphoma?
Hodgkins
Non-Hodgkins
Multiple myeloma
When is elective LN removal indicated for SCC?
When the lesion is larger than 8mm
General Anaesthesia
...
What patients are suitable for GA?
Those that are anxious, phobic, undergoing long stressful procedures
Those that are not very young or very old
Healthy weight
No CVS, respiratory, renal or liver disease
Physically fit
No allergies to anaesthetics
Not pregnant
Those with no family history
What is the sequence of achieving GA?
Fasting (6 hours)
Premedication (midazolam, H2 blockers, atropine)
Induction (stages 1-4)
Maintenance (in stage III)
Emergency/recovery
What is balanced anaesthesia?
Using a combination of medications to achieve desirable levels of anaesthesia with minimal physiological detriments
What system is used to classify patients according to their risk level for undertaking GA?
ASA score out of 5
1-2 can do as day surgery
3-5 require hospital setting
What monitoring equipment is required for GA?
HR monitor
BLood pressure machine
ECG
Pulse oximeter
Capnography
Body temp
What machine is used to deliver the oxygen and gaseous anaesthetic?
Boyles machine
What are some common side effects to GA?
Vomiting
Nausea
Sore throat
What are some rare complications of GA?
Malignant hyperthermia
Awareness during surgery
Anaesthetic toxicity
Death
What are the surgical planes of anaesthesia?
Within stage III of anaesthesia there are 4 planes of anaesthesia. Without the use of muscle relaxants we aim for stage III plane III.
What are the stages of anaesthesia?
Stage I (loss of consciousness)
Stage II (REM, excitability)
Stage III (surgical anaesthesia)
Stage IV (overdose, hypotension, death)
Cranial nerve dysfunction
...
What are some causes of cranial nerve dysfunction?
Trauma
Infection
Neoplasia
Cerebrovascular accident
MS
Sarcoidosis
SLE
Meningitis
What is sarcoidosis?
Granulomatous inflammatory disorder of unknown origin
5% experience cranial nerve dysfunction
What is SLE?
A systemic autoimmune disease involving type III hypersensitivity
What is MS?
An inflammatory disorder in which there is autoimmune destruction of myelin sheaths in the CNS
What may cause olfactory dysfunction?
Le Fort III fracture
Allergic or viral rhinitis
Pupilary light response tests which cranial nerves?
II and III
What muscle does CN VI innervate?
lateral rectus muscle - moves eye laterally
What muscle does CN IV innervate?
Superior oblique muscle - moves eye down and rotates it internally
What does CN III innervate?
Extra-ocular muscles of the eye except superior oblique and lateral rectus. Muscles that raise the eyelids and the ciliary body (for pupil constriction)
Where are the trigeminal motor and sensory nuclei located within the brainstem?
Mesencephalic - pons and midbrain
Chief sensory and motor nucleus - pons
Spinal - medulla
What are some causes of trigeminal dysfunction?
Trauma - nerve blocks, facial trauama, lower 8 osteotomy
Bone disease - Paget's, osteomyeltis, malignancy
Neoplasia - oral, nasal, antral
Other - MS, DM, intracranial lesions (vascular, tumours, cavernous sinus infection neurogenic, psychogenic
Total loss of all three divisions of the trigeminal indicates a lesion where?
At ganglion or sensory root
If there is total loss of sensation in one only one division of trigeminal where is the lesion?
Post-ganglionic
What division of trigeminal is most commonly affected by dysfunction?
V1 due to cavernous sinus infection and orbital fracture
Where is the lesion if you have loss of pain but still have touch in the trigeminal dermatome?
Brainstem or upper cord (ie spinal nucleus)
Where is the lesion if there is loss of touch but still have pain?
Within the pontine nuclei
Where is the lesion if you have motor loss to the muscles of mastication?
Central or peripheral lesion effecting the trigeminal nerve
What tests are required to assess the trigeminal nerve?
Test sesnsation in all divisions
Check corneal reflex (V1, VII)
Palpate muscles of mastication
Observe jaw opening and biting on a wooden spatula
Jaw jerk (masseter) reflex to test for UMN lesion
What is trigeminal neuralgia?
Severe unilateral paroxysmal pain lasting seconds, affecting one or more of the branches.
Usually over 50
Trigger zones
What causes trigeminal neuralgia?
Pontine lesion or compression of the nerve by vasculalar abnormality
What investigations would you perform if suspecting trigeminal neuralgia?
Exam and radiographs to exclude odontogenic or muscular source
If young consider CT/MRI
Response to carbamazipine usually diagnostic
What is the treatment for trigeminal neuralgia?
Carbamazepine/phenytoin (anticonvulsants, stabilises Na channels)
Surgical therapy (nerve blocks, cryosurgery, neurectomy, ganglion procedures)
What are some tests for assessing the facial nerve?
Look for facial asymmetry
Test facial muscle power (wrinkle forehead, smile, puff cheeks, compare nasolabial grooves, shut eyes tight)
How do you differentiate between UMN and LMN lesions of the facial nerve?
UMN lesion - sparing of frontalis and orbicularis oculi (upper spares upper), lower facial muscles on the contralateral side affected, may still have involuntary movement
LMN - all muscles affected on that side
Explain why the upper facial muscles are spared by an UMN lesion.
Because the upper facial nucleus has bilateral input from the cortex while the lower facial nucleus only receives contralateral input.
What are some causes of facial nerve dysfunction?
Bell's palsy
Trauma
Otitis media
Parotid tumour
Cerebrovascular accident
Herpes Zoster of the geniculate ganglion (Ramsay Hunt syndrome)
Sarcoidosis
Lyme disease
Guillain-Barre syndrome
What is Bell's phenomenon?
The upward and outward rotation of the eye when an attempt to close the eye is made. This occurs in everyone but is only observable in Bell's palsy
What causes Bell's palsy?
Herpes infection more common in pregnancy, diabetics, or respiratory illness
What is the treatment for Bell's palsy?
Prednisilone 1mg/kg and aciclovir 5x daily for 10 days
Prognosis is good
What is a serious ddx for Bell's palsy?
Nerve compression around stylomastoid canal from a acoustic neuroma, bone disease
What is bulbar palsy?
Vascular/demyelination insult to the medulla affecting CN IX, X, XI and XII
What are the signs and symptoms of CN IX dysfunction?
Impaired pharyngeal sensation and taste
Gag reflex affected (tested with CN X)
Glossopharyngeal neuralgia
What are the signs and symptoms of CN X dysfunction?
Paralysis of soft palate and larynx
Dysphagia
Hoarseness
If bilateral: tachycardia, decreased respiration, inability to speak or breath
What are the signs and symptoms of CN XI dysfunction?
Weakness turning head away from the affected side
Weakness in shrugging
What are the signs and symptoms of CN XII dysfunction?
Tongue wasting on the affected side
Difficulty with speech
Tongue moves toward the affected side
Dental Disease of the Maxillary Sinus
...
What are some causes of acute maxillary sinusitis?
URTI
Maxillary teeth periapical infection or following exo
What are the most common causative organisms of acute maxillary sinusitis secondary to an URTI?
Viral usually
Bacteria - Strep pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Staph aereus
Fungi - Immunocompromised patients only
What is the management of acute maxillary sinusitis?
Decongestants - ephidrine drops
ABs - 2 weeks of Amoxicillin 500mg tds
Analgesia as required
What are some signs of an OAC?
Reflux of fluids into the nose
Escape of air into the mouth
Recurrent sinusitis
Proliferation of soft tissue around the fistula
What are some risk factors for OAC?
Upper 4,5,6,7,8
Increased age and pneumatisation
Lone standing molar
Why is it desirable to repair an OAC?
To prevent sinus infection
How would you repair a OAC?
Buccal advancement flap with two relieving incisions
Greater palatine rotational flap
What is the Caldwell-Luc procedure?
Where the maxillary sinus is accessed through the anterior wall in the canine fossa
Management of the medically compromised patient
...
What is the definition of medically-necessary dental care?
Oro-dental care that is a direct result of, or has a direct impact on, an underlying medical condition.
Give some examples of medically-necessary dental conditions.
Cleft palate, chemo patients, head and neck radio therapy patients, immuno-suppressed patients, heart valve defects, renal dialysis, diabetes
Are self completed medical history questionnaires accurate?
No
Is a medical history interview accurate in collecting medical history?
No
What is the definition of heart failure?
Failure of the heart to supply sufficient blood flow to meet the body's needs
What are some common causes of heart failure?
MI, hypertension, valvulopathy, cardiomyopathy
Give some examples of systemic disease that have oral manifestations
Lichen Planus
Pemphigus
Crohn's
Leukaemia
Sjogren's
What is the most accurate method of collecting a patient history?
A combination of self completed questionnaire and an interview.
What dental implications are there for a heart failure patient?
May require a pretreatment assessment for suitability for anaesthesia/LA (BP, ECG, bloods etc), resuscitation equipment should be on hand, prophylactic ABs may be required, monitoring equipment may be required (pulse ox, BP), late morning appointment, avo
What are some likely comorbidities the cardiac surgery patient?
Ischaemic/congestive heart disease
Systemic/pulmonary hypertension
Renal disease
DM or other endocrinopathies
AF
Drug induced coagulopathy
Smoking
What is acetylsalicyic acid?
Aspirin
Does Aspirin increase bleeding time?
Low risk unless high doses
How does clopidogrel work?
It inhibits the ADP chemoreceptor on the cell membrane of platelets
What drugs may potentiate warfarin?
Metronidazole
Azole antifungals
Penicillins
Erythromycin
What does INR need to be before surgery?
<3.5-4
What is a side effect of beta blockers?
Postural hypotension
What does digoxin do and what is it used for?
It stabilises cardiac contractility
It is used for AF
What are some implications for the patient taking ACE-inhibitors?
Lichenoid reactions, oral ulcers, glossitis and xerostomia
Cough
Use of NSAIDs diminishes the efficacy of the drug
What are the implications for the patient taking calcium channel blockers?
Gingival enlargement
Postural hypotension
What are the implications for the patient taking diuretics?
Postural hypotension
Xerostomia
NSAIDs may diminish the effect of loop diuretics
Withdraw diuretic morning of surgery to avoid hypotension
What oral bacteria has high affinity for the heart valves?
Strep Viridans
How long following bypass surgery, stent placement or valve repair should dental procedures be avoided for?
3 months
What heart conditions require AB prophylaxis?
1. Previous infective endocarditis
2. Rheumatic heart disease in Indigenous Australians only
3. Prosthetic heart valve
4. Cardiac transplant with subsequent valvulopathy
5. Congenital heart defects if it involves: unrepaired defects, repaired defects with
What procedures require AB prophylaxis if there is also a heart condition requiring it?
Exo
Perio
Replanting avulsed teeth
Other surgical procedures (implants, apicectomy
Consider it for: perio probing, supragingival scaling, retraction cord use etc)
Do you need AB prophylaxis for endo?
Not unless it goes beyond the apex
List three COPD conditions
Chronic bronchitis
Emphysema
Asthma
What comorbidities are likely in COPD patients?
Ischaemic heart disease
Diabetes
Hypertension
What are the dental implications for treatment for a COPD patient?
Best treated upright
Rubber dam may not be tolerated
Avoid bilateral mandibular blocks
Avoid benzos as these depress respiration
Consider giving oxygen at 2-3 L/min
Avoid GA and high dose NO
What meds may someone with COPD be on and what are there dental implications?
Steroid inhaler predisposes to candidiasis
Beta 2 agonists, anticholinergics, theophylline and corticosteroids can cause xerostomia
Theophylline potentiated by some ABs
Long term steroid use - adrenal suppression, immune suppression, hypertension, DM, ost
What dose of prednisolone is sufficient to produce adrenal suppression?
A dose of 10mg or more for 3 months or more
What is diabetes?
A metabolic disease where blood sugar levels are increased due to either not enough insulin being produced by the pancreas or or because cells do not respond to the insulin that is produced.
What is type 2 diabetes?
A metabolic disease characterized by insulin resistance, which may be combined with relatively reduced insulin secretion.
What is type 1 diabetes?
Insulin deficiency due to autoimmune destruction of beta islet cells of the pancreas. Type IV hypersensitivity reaction.
What are the other two forms of DM?
Gestational and secondary (to removal of the pancreas)
What is the upper BSL limit for dental treatment?
16mmol/L however treating the problem may reduce the BSL in itself
What are the dental implications for treating a diabetic patient?
Infections, including perio, needs to be treated aggressively
Infections can destabilise glycaemic control
Lichenoid reactions to anti-glycaemic agents
What are the dental implications for transplant patients?
Oral mucositis following haemopoietic stem cell transplantation and total body irradiation
Immunosuppressants - infections, oral carcinomas, Kaposi sarcoma, lymphoma
Graft vs host disease - lichenoid reactions, xerostomia
Need to ensure meticulous OH and
How long after transplant surgery should elective dental care be deferred?
6 months. If treatment is required during this period AB prophylaxis is warranted.
How long following joint replacement are prophylactic antibiotics required for medium to high risk dental procedures?
3 months
After three months post joint replacement what are some reasons why AB prophylaxis may be indicated for certain dental treatments?
Failing artificial joint
Immunocompromised (DM, HIV)
What is another name for warfarin?
Coumadin
How is coumadin metabolised?
Metabolised by hepatic cytochrome P450 enzyme and excreted in the urine
What is the half life of coumadin?
Terminal half life 1 week
Effective half life ~2 days
How is warfarin absorbed?
Complete absorption by the GIT with peak plasma concentration within 4 hours
What conditions may warfarin be prescribed for?
DVT
PE
AF
Prosthetic heart valves
Coronary heart dz
Protein S or C deficiency
What drugs may interact with warfarin to increase INR (ie potentiate the effects of warfarin)?
Antifungals (miconazole)
Antibacterials (metronidazole, penicillins)
Antimalarials
Oral diabetic agents
NSAIDs
Diuretics
SSRIs, antidepressants
PPI's/H2 blockers
What drugs may interact with warfarin to decrease INR (ie inhibit the effect of warfarin)?
Antiarrhthymics
Antidepressants
Antacids
Antihisamines
Diuretics
OCP
How does metronidazole potentiate warfarin?
Unknown but maybe via inhibition of cytochrome P2C9
What is the target INR for DVT prophylaxis?
2-2.5
What is the target INR for treating DVT, PE and AF?
2-3
What is the target INR for recurrent DVT/PE, myocardial infarction and prosthetic valves?
3-4.5
How do you treat excessive warfarin anticoagulation?
Vitamin K IV/oral
If emergency bleeding 200-500mL fresh whole blood or FFP or factor IX replacement
How long after starting warfarin does it start working, why?
A few days because of the long half life of clotting factors.
What should INR be below for IAN block, exo and full clearance?
IAN block - <3.5
exo - <3
Full clearance - switch to heparin and undertake as inpatient procedure
What are two forms of stroke?
Haemorrhagic
Ischaemic
How long after a stroke should elective dental treatment be deferred?
3-6 months
What precautions can be taken by the dentist in the stroke patient?
Seat upright
Monitor BP
Consider anticoagulant status before giving NSAIDs
What drugs may the stroke patient be on?
Antihypertensives
Antiplatelet therapy
Anticoagulants
What is anaemia?
Hb concentration below the normal for the age, gender and ethnic background of the individual. It may be due to insufficient RBC numbers or Hb content.
What does Hb have to be below to call it anaemia?
< 11 (children)
< 11.5 (women)
<13.5 (men)
What are the signs and symptoms of anaemia?
Patients that are anaemic may be so due to Fe, B12 and folate deficiency.
Iron deficiency anaemia- ulceration, candidiasis, angular cheilitis, mucosal atrophy, increased risk of leukoplakia and SCC
B12, folate deficiency anaemia - ulceration, burning tong
How do you manage recurrent aphthous ulceration?
Chlorhex m/w (Savacol 0.2%)
Benzydamine m/w or spray (Difflam)
Betamethasone m/w (0.5mg tab dissolved in 5ml water)
Triamcinalone cream 0.1%
Avoid abrasive food
How would you treat angular cheilitis?
Miconazole gel
What is Patterson-Kelly syndrome also known as?
Plummer-Vinson syndrome or sideropenic dysphagia
What are the characteristic of Plummer-Vinson syndrome?
Glossitis, dysphagia, oesophageal webbing
Hypochromic anaemia
Occurs in postmenopausal women of northern European descent
Anaemia and sedation
Caution
Give supplemental O2
NO contraindicated for B12 deficiency
Postpone GA till Hb normal
In emergency give whole blood
What is the function of the liver?
CHO - glycogenesis, glycogenlysis, gluconeogenesi,
Protein - clotting factors I (fibrinogen), II (prothrombin), V, VII, IX, X, XI. Also albumin, complement and transporter proteins.
Fat - lipoprotein, cholesterol and phospholipid synthesis, oxidation of t
What do the presence of anti-HBsAg, anti-HBsAb and HBcAg indicate?
anti-HBsAg: acute exposure
anti- HBsAb: infected or vaccinated and immune
anti- HBcAg: current or recent infection taken from liver biopsy
How effective is the hep B vaccine?
90%
What are the clinical signs of alcoholicliver disease?
Jaundice, ascites, spider naevi, distended abdominal veins, clubbing of fingers, dupuytren contracture, gynocaomastia and testicular atrophy, scant body hair
What are the dental implications of liver disease?
Bleeding tendency (check FBC, APTT, PT, INR, bleeding time and liver function test)
If PT reduced give vitamin K for 7 days preop or FFP infusion preop.
Consider AB prophylaxis to prevent bacterial peritonitis
What drugs are contraindicated in the presence of liver disease?
NSAIDs and aspirin (bleeding)
Codeine and some opiods
Many ABs (excluding amoxicillin, cephalexin)
Antifungals (excluding nystatin, fluconazole)
Caution with LA (Citanest safer option due to lung and kidney metabolism)
What is the protocol to follow following needle stick injury?
Bleed, wash, report it
Obtain bloods from patient and healthcare worker
Followup bloods at 6 weeks and 6 months to check for seroconversion
Double gloving for blood born disease?
Mandatory in NSW if performing surgery
What are the consequences of having end stage renal disease?
Na+ retention, weight gain and hypertension
Acidosis and hyperkalaemia
Vitamin D deficiency and calcium loss through the urine with secondary hyperparathyroidism
Pulmonary oedema
Uremic encephalopathy
Anaemia (no EPO)
Immune suppression (toxic pancytopaen
What are the effects of secondary hyperparathyroidism?
Osteoporosis and Brown's tumours, osteomalacia and rickets (in children)
What are the oral manifestations of end stage renal disease?
xerostomia (diuretic use)
Increased calculus (hypercalcaemia)
Uremic stomatitis
Loss of lamina dura
Brown's tumours
When should surgery be performed in relation to timing of renal dialysis?
Within 12-24 hours of dialysis
What pharmacological measures can be taken to assist haemostasis?
Vitamin K
Demopressin (synthetic ADH causes release of vWF and subsequent increased survival of factor VIII)
Why is AB prophylaxis indicated for dialysis patients?
At risk of IE due to chemical trauma to the endocardium during long periods of uremia.
List some factors affecting prognosis for SCC
Stage
Site
Thickness
Degree of differentiation
Nodal and extracapsular spread
Socioeconomic status
Age
Lifestyle (smoking, drinking)
Treatment success
Comorbidities
How deep does an oral SCC have to be to warrant neck LN dissection?
4mm
What are some high risk lesions (red flags) for oral SCC?
Non-healing ulcers
Red patch
Mixed red/white patches
Sensory changes
Progressive swellings
Loose teeth
Describe the management of oral SCC following diagnosis by biopsy.
Multidisciplinary meeting
Primary treatment (resection)
Histological findings (margins, depth of invasion, extracapsular spread, neural invasion etc)
Adjuvant therapy as required (chemo, radio, further resection, LN removal)
Life long follow-up
What fails to fuse with cleft lip?
Maxillary and median nasal processes. Occurs during week 5-7 of embryonic development. Maxilla and mandible develop from 1st pharyngeal arch.
What fails to fuse in cleft palate?
Failure of fusion of the lateral palatine processes and nasal septum, and/or median palatine processes (aka primary palate)
Describe the pathogenesis of ketoacidosis
Lack of insulin
No glucose in cells (high blood glocose)
Counter regulatory hormones rise (glucagon, cortisol, catecholamines)
Gluconeogenesis strongly switched on
Fatty acids broken down to provide acetyl CoA for CAC.
CAC stall due to consumption of oxal
What is a compound fracture?
Fracture that communicates with the exterior
What is a comminuted fracture?
Multiple fragments
What is a simple fracture?
Fracture not in communication with the exterior
What is a greenstick fracture?
Distortion without discontinuity (often in kids)
What are some broad diagnostic categories for neck swellings?
Congenital
Infectious
Traumatic
Neoplastic
Vascular
What are some causes of a pulsatile lump in the anterior triangle of the neck?
Carotid aneurysm
Tortuous carotid
Carotid body tumour
What are some causes of a non-pulsatile lump in the anterior triangle of the neck?
Lymphadenopathy
Thyroglossal cysts
Dermoid cyst
Branchial cyst
Pharyngeal pouch
What are some causes of lumps in the posterior triangle of the neck?
Lymphadenopathy
Cervical rib
Subclavian aneurysm
Lipoma
Neurofibroma
Sebaceous cyst
What are three causes of lymphadenopathy?
Localised infection
Generalised infection (Infectious mononucleosis, TB/HIV)
Neoplasia (lymphoma, leukaemia, mets)
What are some causes of midline neck swellings?
Thyroglossal cysts
Goitre
Lymphadenopathy
Plunging ranula
Pharyngeal pouch
What are some causes of salivary gland swellings?
Infection (mumps, bacterial secondary to dehydration/diabetes/alcoholism)
Autoimmune (Sjogrens)
Calculi
Benign mass (Pleomorphic adenoma)
Malignancy
What is the first line diagnostic test for a neck swelling?
FNA
Then MRI, CT, US
Any adult with a lump in the lateral neck.....
has cancer until proven otherwise
What cellular checkpoint does p53 act at?
G1-S
Ameloblastoma is a.......
benign but locally invasive neoplasm
Surgical Endodontics
...
viva question: What is your treatment plan for this endo treated tooth, including procedures, materials, indications for apicectomy.
...
What are the options for failed RCT?
Retreat
Apicectomy
Combination of both
Implant
Why may an apicetomy with an RCT that looks perfect on radiographs fail?
Failure to disinfect lateral canals properly
What are some situations where orthograde treatment is contraindicated?
Crown covered tooth
Access may jeopardise the remaining core or root
Calcified canals, broken file in canal, apical 1/3 fracture
In these situations surgical endo may be indicated
Which teeth does surgical endo work best on?
Anterior teeth
Low success rate on molar teeth
What must be present prior to performing apicectomy?
A high quality RCT
What condition should be rued out prior to performing apicectomy?
Vertical root fracture
What is the success rate of RCT vs apicectomy?
RCT ~ 85%
Apicectomy ~ 70%
What are the indications for surgical endo?
Persistent periapical disease in RCT teeth where orthograde treatment has failed or cannot be undertaken
When biopsy is required
When direct visualisation is required (perforation, root #)
When root amputation/hemisection required
What are the contraindications for surgical endo?
Mecially compromised
Local anatomical factors (proximity to IAN/sinus, poor perio prognosis, unusual root or bone morphology)
Inexperience of the operator
When implants may be performed for less
What are the options in mucoperiosteal flap designs for apicectomy?
Intrasulcular or submarginal
What are the advantages and disadvantages of intrasulcular vs submarginal flap designs?
Intrasulcular - fibrous contraction leads to gingival recession
Submarginal - requires 5mm of gingival tissue coronal to the incision but offers better aesthetics if high smile line.
What is the procedure for apicectomy?
LA
Flap (submarginal vs intrasulcular)
4-5mm bone removal apical to estimated length
Amputate 3mm of apex at 90 degrees
Remove 3mm of GP retrograde
Fill with MTA (gold standard), amalgam, IRM, fuji IX
Primary closure with prolene 5/0 with removal 2-4 days
What makes MTA superior to other filling materials for apicectomy?
Provides better seal and biocompatibility
May allow for regeneration rather than repair
Releases OH ions -> bacteriocidal
Reconstructive Surgery
...
What are 4 general ways to reconstruct a surgical defect?*
Primary closure
Grafting
Flap techniques
Non-biological materials
What is an autograft?
Autogenous tissue harvested from individual and inserted into the same indivdual
What is an allograft?
A graft transferred between genetically dissimilar individuals of the same species
What is a xenograft?
Graft from animal
What is the difference between osteogenesis, osteoinduction, osteoconduction and osteoprotection?
Osteogenesis - provides a bridge or scaffold
Osteoinduction - active stimulation of osteogenesis (allogenic bone)
Osteoconduction - passive invasion of vascular and cellular components of living bone
Osteoprotection - allows newly formed woven bone to mat
What is a free graft?
autogenous devoid of original blood supply
Orthognathic Surgery
...
What surgical technique is used to move the mandible?
Bilateral sagittal spilt osteotomy (BSSO)
*74 year old man with pain in left maxillary sinus 4 weeks after exo of 27. Discuss investigations, pathophysiology and management.
History (pain hx, salty taste, foul smell, reflux of fluid or food into the nose, air into the mouth during nose blowing)
Exam (blow nose whilst pinching nostrils)
Occipitomental (Water's) view, OPG, CT
Possibly due to OAC following exo (pneumatised antru
42 year old woman with acute pain in maxilla following endo treatment for 14.
Apical extrusion of bacteria or GP into antrum. Analgesia, abs, and monitor.
What are the dental implications for the patient with leukaemia?
May be deficient in RBCs, leukocytes, and/or platelets. Therefore at risk of infection and bleeding.
Oral manifestations include "boggy" severe gingivitis, enlarged LNs due to malignancy, mucosal petechiae and ecchymoses, ulceration.
May have recurrent vi
What is in Gelatamp and what is it used for?
Gelatin sponge and colloidal silver to assist in haemostasis post exo
What are the characteristics of cleidocranial dysplasia?
Delayed loss of primary teeth and eruption of permanent dentition
Peg-like teeth, malocclusion, supernumery teeth
Skeletal deformities (missing clavicles, delayed fontanelle closure, short, wide set eyes, frontal bossing, maxillary retrognathism)
What genes are involved in cleidocranial dysplasia?
Autosomal dominant RUNX2 gene mutation. RUXN2 is a transcription factor. Bone and cartilage affected.
What is the half life of amoxicillin?
1 hour
What disorders may bisphosphonates be prescribed for?
Osteoporosis, Paget's disease of bone and metastatic bone disease
Describe the stages of BRONJ
Stage 0 - no evidence of necrotic bone but non-specific findings such as pain and change in trabecular pattern of the jaws
Stage 1 - exposed necrotic bone for >8 weeks but aysmptomatic and no sign of infection
Stage 2 - exposed necrotic bone with pain and
What serum marker can be used to determine BRONJ risk?
CTX (c-terminal peptide) and estimates bone turnover
CTX < 70 pg/ml = high risk
CTX 70-150 = medium risk
CTX >150 negligible risk
What are some ways of reducing the chance of BRONJ is exo is unavoidable in a bisphosphonate patient?
Minimal trauma technique
Primary closure with sutures
AB prophylaxis if medically compromised (DM or corticosteroids)
What is the window period of Fosomax (alendronate)? What does this mean?
60 months. This means you have to be taking Fosomax for >60 months before the risk developing BRONJ following invasive treatment is increased.
Which radiolucent lesions cause resorption of roots?
Ameloblastoma, CGCG, radicular, dentigerous
What cysts dont cause root resorption?
KOT, aneurysmal bone cyst, simple bone cyst
What are some absolute contraindications of local anaesthetics?
LA allergy
Sulfur allergy (Articaine contraindicated)
Bisulfite allergy (Vasoconstrictor containing LA contraindicated)
What are some relative contraindications for LA?
Methemoglobinaemia (avoid prilocaine and articaine)
Liver and renal failure
Significant cardiovascular disease or hyperthyroidism (avoid high concentrations of vasoconstrictors)
What is haemoglobin?
Iron containing compound in RBCs that transports oxygen around the body
What are some causes of anaemia?
Too few RBCs
Inadequate iron
Low folate or B12
Microscopic blood loss
RBC destruction
Chronic illness
Haemoglobin defect
What are some causes of high haemoglobin?
Chronic lung disease
Adaptation to altitude
What is the hamoglobin concentration cut off for GA?
100g/L in males
What are some oral manifestations of low haemoglobin?
Buring tongue
Atrophic glossitis
Candidiasis
Angular chelitis (Fe deficiency)
Apthae (folate deficiency)
What are some causes of low RBCs?
Anaemia as a result of blood loss
Bone marrow failure
Malnutrition (Fe)
Over hydration
What are some causes of high RBCs?
Congenital heart disease
Lung disease
Dehydration
Kidney disease
Polycythaemia vera (blood cancer)
What is the normal range for WBCs in adults?
4-10x10^9/L
What are soem causes of low WBCs?
Liver or spleen disorders
Bone marrow disorders
Radiation or toxins
Severe infection
What are some causes of high WBCs?
Infection
Leukaemia
Inflammatory disease
Tissue trauma
What are neutrophils and monocytes responsible for?
Protect the body against bacteria and destroy foreign matter
What are lymphocytes responisible for?
Production of antibodies
Protect against viruses and cancer
What are eosinophils responsible for?
Destroying parasites
Allergic response
What are some roal manifestations of leukaemias?
Oral bleeding
Petechiae
Mucosal pallor
Gingival hypertrophy
Mucosal or gingival ulceration
What is the normal range for platelets?
150-400x10^9/L
What are some causes of thrombocytopaenia?
Decreased production (Vit B12/ folate deficiency, leukaemia, liver failure)
Increased destruction (ideopathic thrombocytopaenia purpura)
Medication induced (Clopidogrel, heparin)
What are some causes of high platelets?
Primary - polycythaemia vera
Secondary - inflammation
What may cause a reduction in platelet function?
Aspirin
What are the platelet number cut offs for block injections, minor oral surg and major oral surg?
Block injection - 30x10^9/L
Minor oral surg - 50
Major oral surg - 75
What are some haemostatic measures that may be taken if platelets are low?
Systemic - FFP or platelet transfusion, stop meds
Local - surgicel, suturing, primary wound closure
What does high ALT, AST indicate?
ALT - hepatocellular damage (hepatitis, paracetamol OD)
AST - hepatocelluar damage but also present in cardiac and skeletal muscle and RBCs
What does a high ALP indicate?
Biliary obstruction
Growing children or those with Paget's disease (bone)
What may cause a rise in bilirubin?
Prehepatic: haemolysis, internal haemorrhage
Hepatic: cirrhosis, viral hepatitis
Post-hepatic: Obstructed bile ducts
What does a high GGT reflect?
Minor or sub-clinical liver damage
Alcohol toxicity (acute or chronic)
What are the "coag" test?
aPTT
PT (INR)
Fibrinogen
Platelets
Platelet function test
What does aPTT measure?
Intrinsic and common pathway
Used to monitor heparin
May be prolonged with heparin, haemophilia, antiphospholipid antibody
What does PT measure?
The extrinsic pathway
Used to monitor warfarin (factors II, VII, IX and X)
May be prolonged with with warfarin, liver damage, vitamin K status.
What is INR?
(Patient's PT/lab PT)^x
Normal INR = 0.8-1.2
What blood tests may reveal an autoimmune disease (eg Sjogren's, RA, SLE)?
Antinuclear antibody
Anti SS-A
Anti SS-B
RF
What are some manifestations of vit B12 deficiency?
Anaemia, pallor, breathlessness, listlessness
Atrophic sore tongue
What are some manifestations of folate deficiency?
Anaemia, diarrhoea, weight loss, sore tongue, headache
What is the normal BSL range?
4-8mmol/L
What is a normal HbA1C?
4-6%
Diabetics aim for <7%
What is a Berger flap?
A three sided buccal advancement flap used to close OACs. It includes vestibular epithelium and periosteum and should be closed without tension on the palatal side of the OAC.
What type of flaps are available for correcting an OAC?
Berger flap
Palatal flap
Tongue flap
Buccal fat pad flap
What develops from the 1st pharyngeal arch?
maxilla, mandible, zygomer, temporal bone.
V2 and V3
Muscles of mastication
What develops from the 2nd pharyngeal arch?
Temporal bone, stapes, styloid process.
VII
Muscles of facial expression
What develops from the 3rd pharyngeal arch?
Hyoid bone
IX
Stylopharyngeus
What develops from the 4/6th pharyngeal arch?
The larynx
X
Laryngeal muscles, intrinsic muscles of the soft palate
What measures can be taken to reduce the risk of cleft lip/palate?
Maternal folic acid and multivitamins (~20% reduced risk)
What are the complications of cleft lip and palate?
Feeding difficulties
Dental problems (orthodontic and oral hygiene)
Speech defects
Ear infections and hearing loss
Psychosocial challenges
What are the management steps for a cleft lip/palate patient?
As soon as possible - repair cleft lip to provide 'moulding' to the alveolus and to assist feeding
Within 18 months - repair palatal defect surgically
During childhood - may require pharyngoplasty, ortho or bone grafting
Teenage years - complete comprehen
What other cleft defects may be present with cleft lip and palate?
Clefting of the heart, spine, genitals, brain etc.
What is cleidocranial dysplasia?
Hereditary congenital disorder where there is delayed ossification of midline structures especially membranous bones.
Clavicles partly missing
Maxillary hypoplasia
Supernumery teeth
Occasional cleft palate
Frontal bossing
What other syndromes may present with cleft lip/palate?
Down syndrome, Treacher Collins (lateral drooping of palpebral fissure, deficiency of malar and auricles)
What causes cleft lip and palate?
Unknown
Associated with over 300 syndromes
In non-syndrome cleft cases genetics only plays 20-30% role.
Vitamin deficiencies, radiation, viruses have also been implicated.
What are the chances of a parent having a second or third child with a cleft?
2-5% for a second.
10-15% if there are multiple cleft children already.
For syndromic clefts, the chances can be as high as 50%.
What are the implications for feeding a baby with cleft palate?
Can't produce the normal sucking pressure required for regular breast feeding. Require an elongate nipple to deliver milk deeper into the baby's mouth.