2015 paper Flashcards
Why is non setting calcium hydroxide an ideal inter appoinment medicament
pH = 12.5 - contributes to antimicrobial activity
Effective in removing tissue debris
Adhere directly to dentine rather than restorative material
What is aim of obturation
Traps remaining microorganisms within the root canal
Blocks apical foramina and dentinal tubules and accessory canals#
Prevent passage of micro-organisms and fluid aling root canal
Components of GP
Radiopacifier = (15%)
Zinc Oxide (65%)
Plasticiser (5%)
Reasons for using sealers
Seals between detintal wall and core
Fills voids and irregularities in canals and between GP points
Lubricates during condensation
2 characterstics of biofilm ECM that enable resistance to antimicrobials?
Biofilm impairs diffusion of antimicrobials
Biofilm has adhesive properties which trap antimicrobials and can be destroyed by enzymes
Extracellular DNA and biofilm specific resistance gene
2 bacteria involved in Perio
P.gingivalis
Prevotella intermedia
2 bacteria involved in caries
Streptococcus mutans
Lactobacilli
2 key features that allow carious bacteria to adhere and survive in acidic environment
adhesins
binding proteins - glucan binding protein
sugar modifying factors - fructanase, dextranase
2 systemic diseases related to perio
Diabetes
CVS
Rhemuatoid arthritis
What are ideal thermal properties of acrylic denture base and why
High softening temp - must not distort during ingesitng of hot fluids or cleaning
Thermal expansion same as artifical tooth to avoid internal stresses on cooling during manufracture
Mould liner used in making acrylic denture
Reduces porosity
Easier to carry out de flasking
What is gasous porosity
Shows fine uniform bubbles/ voids in thicker regions
Occurs due to exothermic reaction of polymerisation
Need efficent polymerisation to give high molecular weight polymer
Fast curing leads to gasous porosity
Why do you keep denture in moist environment outside the mouth?
Prevent infection More comfortable in patients mouth For retention If over dried can go brittle Shape can change and no longer fit
What are 2 impression materials used for lower complete dentures?
Alginate
Polyether
Silicone
What is the defnitive name for master impressions
Secondary/definitive impressions
2 factors affecting physical retention
Border seal
Post dam
2 anatomical features used for position of upper posterior border
Hamular notches
Palatine fovea at vibrating line
Border of hard palate
3 anatomical features to include on lowers
Buccal shelf
Residual ridge
Retromolar pad
Maxiallry sinus border
Inferior border
Horizontal line for OPT parallel to floor
Frankfort plane
What happens if antrior are horizontally magnified
Patient too far back in machine
Canine behind the guidance mark
Posterior horizontally wider on one side
Patient rotated in machine
What type of radiograph would you do for pre XLA of 48 only
Right half panoramic
What type of radiograph do you do for a child that can’t tolerate BW’s
OPT - setting 4
What is a null hypotheisis
General statement suggesting no statistical significance in set of data
What is xerostomia
Reduced or absent saliva flow
When flow of saliva <0.3ml/min of unstimulated saliva flow
What are the oral impacts of xerostomia
Increased caries risk Increased perio risk Candidosis Dental erosion Sialadentitis - infection of salivery gland
Medications that cause xerostomia
Diuretics Beta blockers Anti covulsants Antidepressants Anti psychiotics
What are other causes of xerostomia
Radio and chemo Parkinsons Sjorens Syndrome Cystic fibrosis Rheumatoid Arhtritis
2 modifications to enable wheelchair patient to get to first floor surgery
ground floor access
Handrails for support
Wide doors and corridors for wheelchairs
Wheelchair turning circle within surgery
2 methods to communicate if cant write etc
Makaton
Picture boards
Talking mats
How to get patient into suitable position for exam
Stand aid
Hoist
Banana Board
Wheelchair recliner
Mouth access with cerebral palsy is difficult why?
Due to random and uncontrolled and muscle weakness/stiffness
2 non pharmocological management for mouth access problem
Bedi shield
Open wide mouth rests
Toothbrush
XLA 45 - what nerves are anaesthetised?
Inferior dental nerve
Lingual nerve/mental nerve
How do you test anaesthesia?
Numbness of tongue and lower lip
Gently probe around area of tooth and determine if any pain felt
3 possible nerve deficity
Anaesthesia (numbness)
Paraesthesia (tingling)
Dysaesthesia (unpleasant sensation/pain)
What are 3 causes of nerve damage?
Crushing on removal of tooth
Cutting/shredding due to LA
Damage to nerve in surgery
Damage due to LA
Upper 1 not erupting after decidious fell out due to trauma
What do you do on first interaction with patient
Take medical and dental history Radiographs and exams Palpate the buccal sulcus Maintain space Monitor for 1 1/2 years Refer for ortho Surgical exposure - bond with ortho gold chain
2 causes of failed eruption of permanent tooth
Trauma
Unerupted supernumary preventing eruption
Abnormal developmental position
4 principles of ortho management for non eruption of 11
Create space Bonded retainer Surgical exposure Remove supernumary Monitor 1 1/2years
When is a suitable XLA time for lower 6’s
Bifurcation of 7’s
Presence of 5’s and 8’s on xrays
Class 1 incisor relationship
TX plan for non carious upper 6’s
Compensating XLA
What are 2 advantages of XLA 6’s at right time?
Caries free dentition
Spontaneous eruption of 7’s and space closure
Reduction of ortho
2 disadvantages of XLA 6’s
Bad experience for child
Loss of a permanent tooth
GA risk
3 PPE for carrying out manual cleaning and why?
Marigold gloves - protect hands from detergent which is iriitant
Plastic disposable apron - protect clothes from splashes when washing
Plastic visor to protect against aerosol during washing contaminated instruments
When do you degas an ultrasonic and why?
Degas after filling from empty to remove air/oxygen from water
You degas oxygen asd can have affect cavitation and instrumentes may not be cleaned correctly
2 examples of manual cleaning
Immersion - non lumen devices, mirros, probes
Non immmersion - lumened devices, handpieces
Why use deionised water in sterilisers?
Prevents deposists of minerals on machine and instruments
4 reasons that make you suspect trauma is non accidental
Delay in seeking help Account not compatible with story Injuries to both sides of the body Injuries with a particular pattern Injuries to soft tissues
2 effects of trauma on decidous teeth
Discolouration
Discolouration and infection
Delayed exofoliation of tooth
4 effects of trauma on permanent successor
Hypoplasia Hypomineralisation delayed eruption Ectopic eruption Damage to crown development Damage to root development (dilaceration)
