307 - support for control of periodontal disease, caries & restoration of cavities. Flashcards
What is the main microorganism that causes caries?
Streptococcus Mutans
What does ANUG stand for?
Acute Necrotising Ulcerative Gingivitis
What is a consequence of advanced periodontal disease?
Mobility
Main advantage of Calcium Hydroxide lining?
Promotes secondary dentine formation
What is a push scaler used for?
Removal of interproximal calculus
What may indicate signs of bruxism?
Attrition
What is an additional advantage zinc oxide and eugenol cement has over other linings?
Chemically calms the tooth
What material requires the presence of undercuts to remain in place?
Amalgam
What instrument carefully removes carious tissue without exposing the pulp?
Spoon excavator
What is the main component of amalgam?
Silver
Which material chemically prepares tooth surface for a composite restoration?
Phosphoric acid (etch)
What lining should not be used under a composite restoration?
Zinc oxide and eugenol cement
What is used for a class II restoration?
Siqveland matrix band
What is the most likely classification for abrasion cavities?
Class V
What advantage does glass ionomer have over composite?
Releases fluoride
What are harmful sugars known as?
Non-milk extrinsic
What is the pH level of the mouth during demineralisation?
pH 5.5
Inflammation of the periodontum is periodontitis. What finding helps to diagnose it as not being gingivitis?
True pocket
Before periodontitis develops, chronic gingivits occurs. What is most likely to be present?
Gingival hyperplasia (inflamed/overgrowth of gums)
what are cavities caused by?
dental caries attacking hard structure of tooth
what is a treatment plan for a cavity based on?
cavity size
cavity position
tooth involved
extent of caries
who can carry out a filling in line with GDC scope of practice?
dentist or dental therapist
on what patients are temporary restorations placed on?
less co-operative patients
what materials are used as temporary restorations?
zinc oxide and eugenol cement
zinc phosphate cement
zinc polycarboxylate cement
where are amalgam restorations usually placed?
on posterior teeth
where are composite restorations placed?
anterior teeth for aesthetics and also in posterior teeth too
where are glass ionomer cement restorations placed?
in deciduous teeth and in cavities where retention is difficult
why is glass ionomer used in deciduous teeth?
releases fluoride
what are the aims of cavity preparation?
remove all caries without pulp exposure
avoid accidental pulp exposure
protect pulp by using linings/bases
how many classifications are there for cavities?
5
what are cavity classifications based on?
site of original caries attack
what is the name of cavity classifications?
Black’s classification
class I cavity
single surface
in pit/fissure
e.g. occlusal/buccal/lingual
class II cavity
at least 2 surfaces of posterior tooth
e.g. mesial/distal and occlusal
molar or premolar
class III cavity
mesial or distal surface of incisor or canine
class IV cavity
same as class III but extend to involve incisal edge of affected side
e.g. mesial incisal or distal incisal
class V cavity
cervical margin of any tooth
e.g. labial cervical filling in upper incisor
what does careful cavity prep ensure?
all plaque biofilm and soft carious dentine removed
conserve as much enamel as poss to maintain strength/structure of tooth
reduced chance of micro leakage
function of mouth mirror
aid dentist vision
reflect light onto tooth
retract and protect soft tissues
function of right angle probe
feel cavity margins
feel softened dentine within cavity
detect overhanging restorations
function of excavators
small/large spoon shaped to scoop out softened dentine
function of amalgam plugger
push plastic filling material into cavity and adapt them to cavity shape and leave no air space
force excess mercury out
function of burnisher
ball/pear shaped to press and adapt restoration margins against cavity for no leakages
function of flat plastic
remove excess filling material and create shaped surface
function of college tweezers
pick up. hold and carry items
function of gingival margin trimmer
trim margin of cavity to ensure no unsupported enamel or soft dentine remains
function of enamel chisel
remove unsupported enamel from cavity edges
what is a preconstructed restoration called?
inlay
what material can inlays be?
gold
porcelain
other ceramic material
how is retention for a filling made?
cutting tiny grooves in cavity walls
what is done if there can’t be an undercut in a restoration?
self tapping dentine pins
acid etching for composite
chemical bonding for glass ionomer
how are linings placed?
thin layer on floor of shallow cavity
what does a lining do?
protect underlying pulp against chemical irritation
name an example of a lining…
calcium hydroxide
how are bases placed?
in deeper cavities as thicker layer
what do bases do?
protect pulp against chemical irritation and insulate from thermal changes
name examples of bases…
zinc oxide and eugenol cements
zinc phosphate cements
zinc polycarboxylate cements
how does majority of post-restorative pulp damage occur?
microleakage
small amount of fluid/debris/bacteria leak through microscopic gaps
enter dentinal tubules
contaminate pulp tissue
properties of modern lining materials
chemically bond to dentine
physically seal dentine tubules
insoluble once set
radiopaque - can be seen on radiograph
why can some modern lining materials not be placed on cavity floor?
may cause pulp damage due to chemical composite
why is moisture control important?
protect patient airway from fluid inhalation
ensure patient is comfortable - mouth isn’t full of fluid
allow good visibility
allow restorative material to set correctly
methods used to control moisture?
high-speed suction with aspirator
low speed suction with saliva ejector
absorbent material e.g. cotton wool rolls
rubber dam
3 in 1 to air dry
what does high speed aspiration achieve?
fast removal of moisture during drilling
what does low speed aspiration achieve?
continual moisture control without sucking at soft tissues
what do absorbent materials do?
placed in buccal or lingual sulcus and absorb saliva
keep soft tissues away from teeth
what is a rubber dam?
thin vinyl sheet placed over tooth to isolate it from rest of mouth
what are the 2 main uses of rubber dams?
RCT to maintain sterile field and prevent inhalation
during insertion of fillings to avoid failure due to saliva contamination
at what speed can air turbine handpieces run?
500,000 revolutions per minute
what burs are used to cut through enamel and dentine?
friction grip diamond or tungsten carbide burs
advantage of air turbines?
ease and speed of cutting
disadvantage of air turbines?
little tactile sensation = excessive tooth removal
how fast do slow handpieces run?
40,000 revolutions per minute
what motors are slow handpieces driven by?
air or electric
what are burs for low speed procedures made of?
steel
what do steel burs do?
remove caries, cut dentine, trim dentures
what are burs for high speed procedures made of?
diamond or tungsten carbide cutting surface
what do the diamond/tungsten carbide burs do?
rapid removal of enamel, dentine and old fillings
use of round bur
gain access to cavities
use of pear bur
shaping and smoothing cavities
use of fissure bur
shaping and outlining cavities