What is an OAC?
Oro-antral communication. It is an unnatural communication between the oral cavity and the maxillary sinus that is not yet epithelial lined. IMMEDIATE
Management of an OAC
Buccal advancement flap - with vertical mattress suture
Buccal fat pad
Palatal rotation flap
Give antibiotics (tetracyclines), analgesics and decongestants (ephedrine, xylometazoline)
What is ANUG?
acute necrotising ulcerative ginigivitis. Loss of interdental papillae and halitosis, painful and bleeding gums
Causes of ANUG
Mixed bacterial infection that includes anaerobes. Spirochetes, Fusobacterium nucleatum, Prevotella intermia, Treponema, Borellia vincentii
Predisposing factors - Smoking, stress, poor OH, immunodeficiency, viral respiratory conditions
Treatment for ANUG
OHI, debridement,Short course of systemic antiobiotics - Metronidazole
How does Metronidazole work?
Bacteriacidal against protozoa and anaerobic bacteria. Inhibits DNA synthesis by causing strand breakage of bacterial DNA.
200mg TDS
Disulphuriam like reaction with alcohol
Principles of flap design
Broad base incision on sound bone avoid vital structures full thickness flap include the interdental papillae
What is desquamative gingivitis?
erythematous, shedding, ulcerated appearance of gums. Associated with pemphigus, pemphigoid, lichen planus, dermatitis hepetiformis
NOT PLAQUE INDUCED
What is muscous membrance pemphigoid?
autoimmune Primary vesiculo-bullous disorder. Sub-epithelial. Auto antibodies against the epithelial basement membrane. (IgG and c3 along the basement membrane) Conjunctiva involvement
What is pemphigus
Most common vulgaris. Autoimmune primary vesiculo bullous disorder. Intra-epithelial. IgG mediated against desmoglein 1 + 3
What is an OAF
Or-antral fistula - epithelium lined tract which forms within 48 hours of extraction
What is dysplasia?
Abnormaltiy of development. expansion of immature cells and reduction in mature cells. Moderate and severe dysplastic changes should be excised due to the risk of malignant change
Pathological, microscopic changes in dysplasia?
- Anisocytosis - cells of unequal size
- Poikilocytosis - cells of abnormal shape
- Hyperchromatism
- Increase in mitotic figures
- Drop shaped rete ridges
- lack of cell polarity
- increase in nucleus to cytoplasmic ratio
- loss of intercellular adhesion
When do you extract 8’s?
Evidence of pathology (caries, periapical pathology, abcess, internal/external resporption of adjacent teeth.
Impeding jaw surgery
greater than 2 episodes of pericoronitis
Types of lichen planus
Reticular, erosive, atrophic, plaque-like, papular, bullous
Which types of lichen planus have the worst prognosis
erosive and plaque-like (atrophic)
Points of note when looking at a radiograph showing wisdom teeth
1/ Angluation of tooth
- proximity to the ID neve
- shape of the root
- position of the second molar
- texture of surrounding bone
Differentials of a non-healing socket
SCC, BRONJ, osteoradionecrosis, dry socket
What is chronic erythematous candidosis
Chronic form of candidosis, most commonly seen in denture wearers. Mucosa is erythematous and the mucosa may become nodular –> papillary hyperpalasia
Diagnois - seperate smear/swab of denture and mucosa,
Where do you give an ID block
in the pterygomandibular space. You palpate for the external oblique ridge and advance the needle into the raphe. Usually approach from the opposite premolar area
What is the nerve pathway for the trigeminal nerve
Opthalmic - Superior orbital fissure (sensory)
Maxillary - Foramen Rotundum (sensory)
Mandibular - foramen ovale (Sensory and motor)
Differentials for a unilocular radiolucency in the angle of the mandible
- Radicular cyst - unilocular, well defined at the apex of a non-vital tooth. can displace teeth
- Residual cyst - a remaining radicular cyst after tooth removal
- Dentigerous cyst - remenants of the reduced enamel epithelium after tooth formation, the crown is unerrupted.
- Odontogenic keratocyst - usually associated with an unerupted tooth. Tooth displacement and extensive expansion with cancellous bone
are lesions above the ID canal odontogenic or non-odontogenic
odontogenic
What is a mucocele
an accumulation of mucous either in the connective tissues (extravastation) or in the salivary duct (retention)
What is a ranula
a mucocele inthe floor of the mouth
Herpes labilais
Herpes infection caused by HHV 1 AND 2. Very infectious - symptoms usually begin as a burning/tingling sensation in a localized region
Factors which predispose you to herpes labialis
immunosuppression sunlight hormonal changes stress trauma fever menstruation
What is median rhomboid glossitis
It is an erythematous rhomboid area of depapillation on the dorsum of the tongue in the midline, anterior to the circumvallate papilla, Treatment is by the use of antifunglas
Predispositions to candida
immunosupression systemic steriods diabetes anaemia poor intra-oral appliance hygiene extremes of age malnutrition smoking
What is angular chelitis?
erythema +/- yellow crusting at one or both corners of the mouth, Associated with candidal or staph aureaus infection.
Side effects of systemic steriods
Cushingoid features buffalo hump moon face diabetes hypertension thin skin central obestity fragile hair immunosuppression glaucoma huirsutism gastric ulceration -- DONT GIVE NSAIDS osteoperosis
Geographic tongue
mucosal condition resembles psoriasis histpathologically
irregular depapillated erythematous areas surrounded by pale well-demarcated margins on the dorsal surface and lateral borders of the tongue
unknown aetiology
Herpes zoster
childhood- chicken pox
adulthood - shingles
VZV progresses along the sensory nerves to the nerve ganglia where tit resides in the latent form.
Reactivation characteristically follows suppression due to malignancy, drug administration or HIV infection
ZOSTER DOES NOT CROSS THE MIDLINE
Sialadentis
Viral - Mumps (paramyxovirus)
Bacterial - usually caused by reduced salivary flow - staph aureas, strep viridans and strep pneumoniae. Strictly anaerobes
Dermatitis herpetiformis
primary vesiculo-bullous disease. RELATIONSHIP WITH COELIACS disease. Development of blisters on the skin and oral mucosa, Granular deposition of IgA along the basement membrane
Treatment - dapsone
What is HIV
human immunodeficiency virus that causes AIDS. Transmission through blood semen and breast milk.
Lentivirus/ retrovirus
Attaches to gp120 on cells
Lowers CD4 t-cell numbers
Haemophilia A
Factor viii deficiency
Haemophilia B
Factor IX deficiency
What is Sjogrens
chronic autoimmune disease in which the bodies white cells destroy the exocrine glands
Primary - dry eyes and dry mouth
Secondary - CT disorder in addition to suffering from dry eyes/dry mouth (rhematoid arthritis, SLE, systemic sclerosis, primary biliary cirrhosis)
Histology of lichen planus
Linear deposition of fibrinogen along the basement membrane but no deposition of Igs or complement (with direct immunofluoresence)
Hyperkeratinized epithelium, basal cell destruction and band-like infiltration of t lymphocytes
What is eccymosis
subcutaneous purpura greater than 1cm. ie a bruise not caused by trauma
What is azathioprine
Purine analogue and is an immunosupressive drug. Inhibits DNA synthesis of rapidly diving cells and so strongly affects cells such as B and T cells.
Main adverse effect is bone marrow supression.
What blood test do you do before giving dapsone
Glucose 6 phosphate dehydrogenase
What blood test do you do before giving azothioprine
TPMT - Thiopurine methyl transferase
What is the relevance of TPMT
Patients are tested for it prior to the use of thioprine drugs. Low TPMT increases the risk of drug-induced bone marrow toxicity due to the accumulation of unmetabolised drug
What can you do to test for Candida
- Swab to culture
- take a smear and histologically stain with a PAS stain - stain the carbohydrate in the fungal cell wall magenta
- You can also do a rinse of phosphate-buffered saline
- Mucosal biopsy for chronic hyperplastic candidiosis
What are the indications for prescribing antibiotics
Systemic involvement such as fever, lymphadenopathy, pyrexia.
Pus and trismus
Where can the spread of infection go?
Direct spread – through facial planes/ muscles. ie the path of least resistance
Lymphatics
Veins – cavernous sinus thrombosis
What is a cavernous sinus thrombosis
Formation of a blood clot in the cavernous sinus, which is a cavity that drains deoxygenated blood from the brain back into the heart
Staph aureas and streptococcus are usually the causative agents
Signs and symptoms of a cavernous sinus thrombosis
Decrease loss of vision, drooping or bulging eyes, headaches, paralysis of the cranial nerves (II,IV, V1, V2, VI)
Why do you get a chin point/sub metal swelling when there is pathology associated with the mandibular incisors
There is a thin labial cortical plate and the mentalis attaches above the apices
What is Ludwigs angina
Spreading of infection of the sublingual and submental spaces bilaterally. Occurs bilaterally due to the lack of posterior border of the mylohyoid. The swelling forces the tongue up against the palate which causes airway obstruction
Spread of infection of pericoronitis
- Buccal space
- Cheek space
- Pterygomandibular space
- Tonsilla space
- Retropharyngeal
- lateral pharyngeal
- Sub masseteric
What is pericoronitis
Infection of the operculum or the soft tissues overlying a partially erupted tooth
What is in LA
LA base HCL Salt vasoconstrictor buffering agent preservatives
in which direction should you suture
from free to fixed
Indications for surgical endodontics in the presence of periradicular disease
(with or without symptoms)
1, non-surgical root treatment has failed
2. trauma
3. perforations
4. re-root treatment cannot be undertaken due to obliterated canals, very curved canals, fractured instrument.
5. where a biopsy of the periradicular tissue is needed
What do bisohosphonates do?
They have an affinity for hydroxyapetite crystals and are absorbed by the bone. They inhibit osteoclast mediated bone resorption
What radiographic features show an intimate relationship of the IDN with a wisdom tooth?
- Loss of tramlines
- Narrowing of tramlines
- sudden change in the direction of tramlines
- Radiolucent band across the root
Why does LA work less well in patients with acute infection
- inflammed tissues are acidic and therefore LA is ionised in tissues before it can cross the neural cell.
- Increased vascualrity of tissues - solution is removed more quickly
- Prostaglandins increase the threshold of nerves thus a higher concentration of LA is needed to anaesthetise
Frey’s syndrome
occurs due to surgeries in the parotid gland or due to injury of the auriculotemporal nerve (V3) which passes through the parotid gland
Severence of the nerve can cause inappropriate regeneration of parasympathetic nerve fibres –gustatory sweating
Bacteriocidal antibiotics
Penicillins, metronidazole, cephalosporins
Bacteriostatic drugs
erythromycin, tetracyclines, clindmycin
Allodonyia
Pain caused by a stimulus that doesn’t normally cause pain
Paraethesia
Spontaneous and subjective altered sensation that a patient doesn’t find painful
Dysaethesia
Spontaneous and subjective altered sensation that a patient finds painful
Where are you most likely to come across FNAC
Ultrasound guided in a neck lump clinic enables you to examine cell structure and morphology. NOT TISSUE
Stages of tooth development
bud, cap bell
Potentially malignant lesions in the oral cavity
Oral lichen planus, erythroplakia, leukoplakia, dyskeratosis congentia, submucous fibrosis, acitinic chelitis
What would increase the risk profile of leukoplakia?
Location - FOM, retromolar pad, tongue Colour - mixed red and white Texture - raised and non-homogenous Induration Presence of ulceration
What is leukoplakia
A white patch that cannot be identified clinically or pathologically. It cannot be rubbed off
What is erthyroplakia
A red patch that cannot be identified clinically or pathologically. It has a high risk of malignant transformation.
Causes of SCC
Smoking, genetic, alcohol, betel quid, HPV
Histological features of SCC
Dysplasia, invasion through the basement membrane, perineural and vascular invasion
What is an odontogenic tumour?
A group of heretogenous diseases (benign or malignant) derived form elements of the tooth forming apparatus that contain odontogenic epithelium and/ or odontogenic connective tissue
Odontogenic cysts
Radicular cyst, residual cyst, dentigerous cyst and lateral periodontal cyst
Non-odontogenic cysts
Nasopalatine
Nasolabial
Bone cysts - aneurysmal or solitary bone cyst
Where is the most common place to have a radicular cysts?
Upper laterals. A radicular cyst is in continuity with the lateral periodontal ligament of the affected tooth
What is a residual cyst
A radicular cyst that remains once the causative tooth has been removed
What is a dentigerous cyst?
Remnants of the reduced enamel epithelium after tooth formation. From the crown of and unerupted and displaced tooth
Where does the nasolabial cyst originate
remnants from the embryonic nasolacrimal duct
Multilocular radiolucencies
Odontogenic tumours and giant cell lesions
Giant cell radiolucencies
Aneurysmal bone cyst
Browns tumour of hyperparathyroidism
Cherubism
Central giant cell granuloma
Multilocular odontogenic tumours
Odontogenic keratocyst Ameloblastoma odontogenic myxoma ameloblastic fibroma odontogenic fibroma sialo-odontogenic tumour
Where do odontogenic keratacysts usually occur
Posterior/body of the mandible
anterior maxilla in the canine region
Smooth, scalloped, well defined and corticated
Present commonly in patients with Gorlin-goltz syndrome.
Ameloblastoma
Multilocular. Soap bubble effect. Benign but very aggressive. disfiguring
cysts vs tumour
cysts displace teeth and tumours resorb teeth/roots project into the tumour
Central giant cell granuloma
Occur in the mandible and the main feature is that it crosses the midline. It is multilocular and has a honeycomb appearance
Cherubism
multilocular, bilateral giant cell lesion
Odontomes
odontogenic tumour
Compound odomtome
organised mass of dental tissue. More common in the anterior maxilla. Superficial resemblance to teeth
Complex odontome
unrecongizable as dental tissues, Usually appears in the posterior mandible
Osteomyelitis
Bone infection and inflammation usually caused by bacteria, It can be chronic or acute and the bone has a moth eaten appearance.
What conditions can cause opactities of the antrum
Thalassemia Sickle cell anaemia Fibrous dysplasia Pagets disease of the bone osteopetrosis