toothwear 1 Flashcards
1
Q
what are causes of tooth surface loss
A
- caries, trauma, developmental problems, tooth wear
2
Q
what is the physiological tooth wear
A
- normal
- happens to everyone
- around 20-38µm per annum
3
Q
what is pathological tooth wear
A
- occurs if the remaining tooth structure or the plural health is compromised or the rate of tooth wear is in excess of what would be expected for that age
- it can also be considered pathological if the pt experiences a masticatory or aesthetic deficit
- happens in excess of what is expected
4
Q
causes of tooth wear
A
- attrition
- abrasion
- erosion
- abfraction
5
Q
what is attiriton
A
- the physiological wearing away of tooth structure as a result of tooth to tooth contact
6
Q
where are attractive lesions found
A
- occlusal and incised contacting surfaces
7
Q
what is the early appearance of attrition
A
- polished facet on a cusp or a slight flattening of an incised edge
- progression leads to a reduction in cusp height and flattening of occlusal inclined planes
8
Q
what is attrition almost always associated with
A
- parafunctional habit - bruxism
9
Q
what is abrasion
A
- the physical wear of tooth substance through an abnormal mechanical process independent of occlusion
- it involved a foreign object or substance repeatedly contacting the tooth
10
Q
where is the most common area for abrasion and what is the cause
A
- commonest area if labial/buccal, cervical on canine and premolar teeth
- from toothbrush
11
Q
what shape are abrasive lesions
A
- v-shaped or round
- shape margin at enamel edge where dentine is worn away preferentially
12
Q
what are other causes of abrasion not toothbrush
A
- holdings pins/nails in mouth, electrical wire stripping, fishing line, thread, pipe smoking
13
Q
how can e-cigs cause abrasion
A
- heavier than pipes and getting bigger
- acidic liquid in them = so cause erosion too
14
Q
what is erosion
A
- the loss of tooth surface by a chemical process that does not involve bacterial action
15
Q
what is most common cause of tooth wear
A
- erosion
16
Q
what causes erosion
A
- chronic exposure of dental hard tissues to acidic substances which can be extrinsic or intrinsic
17
Q
what do erosive lesions look like
A
- early stages enamel surfaces are affected, there is loss of surface detail, surfaces become flat and smooth
- typically bilateral, concave lesions without chalky appearance of bacterial acid decalcification
- hollowed out lesions
18
Q
what is a common sign of erosin
A
- ‘cupping’
- preferential wear of dentine leads to cupping of occlusal surfaces of the molars and incase edges
- because enamel wears less than dentine so then get small indents on occlusal surface
19
Q
what do pts usually complain about first with erosion
A
- teeth appearing darker
- because get increased translucency of incised edges so can appear dark from mouth shining through
20
Q
how do restorations react with erosion
A
- tooth dissolves around the restoration and then restoration left standing proud
21
Q
why do you not see staining in erosive pts
A
- because any staining there would have been is washed away by the acid
22
Q
what is abfraction
A
- loss of hard tissue from eccentric occlusal forces leading to compressive and tensile stresses at the cervical fulcrum areas of the tooth
- pathological loss of tooth substance at the cervical margin caused by biomechanics loading forces
23
Q
what are the 2 theories of abfraction
A
- 1 = it is the basic cause of all non-carious cervical lesions
- 2= multifactorial aetiology, a combination of occlusal stress, abrasion and erosion
(more likely 2)
24
Q
what is the process of abfraction
A
- when force is applied to the tooth it bends very slightly and get forces at cervical area which causes micro-stresses on this area and if that happens a lot eventually the enamel and dentine start to fracture off
- disruption of the ordered crystalline structure of the enamel and dentine by cyclic fatigue
25
what do abfraction lesions look like typically
- v-shaped tooth loss where tooth is under tension
- classically shape rim at the ACJ
- could argue it is toothbrush abrasion as looks very similar
26
causes of cervical wear
- multifactorial
- overzealous tooth brushing
- lesions mainly in premolar and molars one buccal surface = never lingual
- good OH and this wear pattern go together
- restorations in this area wear at same rate as the tooth structure
- likely to be a combination of erosion, abrasion and +/- abfraction
27
what s the most common type of tooth wear in older pts
- physiological
28
which gender has more wear
- males
29
how much has moderate wear increased over last 10 years
- from 11% to 15%
30
what to get from pt main complaint about tooth wear
- aesthetic impairment
- functional difficulties = masticatory efficiency, biting of tongue or lips etc
- pain = not common unless rapidly progressing
31
why is pain unlikely in tooth wear cases
- because tooth wear happens slowly and because of that, get a build up of secondary dentine protecting the pulp
- so pulp doesn't come to surface as you wear away teeth, it tends to recede away down the tooth
32
what do you want to know about pts medical history fir wear
- medication causing dry mouth
- medication with low pH
- eating disorders
- alcoholism
- heart burn
- GORD
- hiatus hernia
- rumination
- pregnancy = transient problems, goes away after pregnancy when baby not pushing against stomach and cause reflux
33
what social factors are good to know from pts in wear cases
- lifestyle stresses
- parafuncitonal habits
- alcohol consumption
- dietary analysis
- habits = pipe smoking
- sports = gels for runners high in acid, grind teeth weightlifting etc
34
extra-oral exam for tooth wear
- must examine TMJ for restriction of movement, clicking, crepitus
- examine musculature for hypertrophy
- examine mouth opening for restriction and deviation during movement
- lip line
- smile line
- occlusion = record OVD and RFH
35
why do you need to record occlusion for tooth wear
- often it is normal because tooth wear happens so slowly so OVD/RFH moves with the tooth wear
- get alveolar compensation
- but if tooth wear has happened radpily, then will have a decrease in OVD as not able to keep up
36
what is alveolar compensation
- as teeth wear, the bone holding the teeth goes down and the incised level stays the same
- so teeth get shorter but distance from nose to incised level stays the same
37
what are the two most common wear indices
- Smith and Knight = not so much now
- BEWE
38
how many grades are there in Smith and Knight indice
- 0-4
39
what is grade 0 for smith and knight
- no loss of enamel surface characteristics
40
what is grade 1 smith and knight
- loss of surface enamel characteristics
41
what is grade 2 smith and knight
- buccal, lingual and occlusal loss of enamel, exposing dentine for less than one third of the surface
- incisal loss of enamel
- minimal dentine exposure
42
what is grade 3 smith and knight
- buccal, lingual and occlusal loss of enamel, exposing dentine for more than one third of the surface
- incisa loss of enamel
- substantial dentine exposure
43
what is grade 4 smith and knight
- buccal, lingual and occlusal complete loss of enamel, pulpal exposure or exposure of secondary dentine
- incised pulp exposure or exposure of secondary dentine
44
how does the BEWE indice work
- gives wear a score and a risk level
- was an attempt to simplify the wear measurement
- like a BPE for tooth wear
- easier to do and less open to being subjective
- give each sextant a score
45
how many BEWE scores are there
- 0-3
46
what is a BEWE score 0
- no erosive wear
47
what is a BEWE score 1
- initial loss of surface texture
48
what is a BEWE score 2
- distinct defect; hard tissue loss <50% of surface
49
what is a BEWE score 3
- hard tissue loss >50% of the surface area
50
what are the risk levels of BEWE
- none= cumulative score of all sextants ≤2
- low = cumulative score of all sextants 3-8
- medium = cumulative score of all sextants 9-13
- high = cumulative score of sextants ≥14
51
what special tests are needed for tooth wear
- sensibility testing
- radiographs
- articulated study models
- intra-oral photographs
- salivary analysis
- diagnostic wax-ups
- dietary analysis
