Tooth Wear

Question 1

Examples/causes of non-carious tooth surface loss

Answer 1

trauma
developmental problems
tooth wear

Question 2

types of tooth wear

Answer 2

physiological tooth wear
- normal physiological process, increases with age and associated with normal function
- estimates vary from 20-38um per year

pathological tooth wear
- occurs if remaining tooth structure or pulapal health is compromised
- OR rate of tooth wear is in excess of what would be expected at that age
- also considered pathological if patient experiences a masticatory or aesthetic deficit

Question 3

causes of tooth wear

Answer 3

attrition
abrasion
erosion
abfraction

Question 4

attrition - define

Answer 4

the physiological wearing away of tooth structure as a result of tooth to tooth contact

Question 5

features of attrition

Answer 5

• attritive lesions found in occlusal and incisal contacting surfaces
• early appearance is polished facet on cusp or slight flattening of an incisal edge
• progression leads to reduction in cusp height and flattening of occlusal planes
• can be a shortening of the clinical crown of the incisor and canine teeth

Question 6

pathological attrition - cause

Answer 6

almost always related to parafunctional habit (bruxism)
restorations show same wear as tooth structure

Question 7

abrasion - define

Answer 7

physical wear of tooth structure through an abnormal mechanical process independent of occlusion
- involved a foreign object or substance repeatedly contacting the tooth

Question 8

abrasion - common clinical features and signs

Answer 8

site and pattern of tooth loss related to abrasive element
most common is labial/buccal, cervical on canine and premolar teeth
v shaped or rounded lesions
Sharp margin at enamel edge where dentine is worn away preferential

Question 9

causes of abrasion

Answer 9

most common = tooth brushing
others = pins, nails, electric wire stripping, fishing line, pipe smoking, thread

Question 10

erosion - define

Answer 10

loss of tooth surface by chemical process that does not involve bacterial action
- most common cause of pathological tooth wear

Question 11

erosion - causes

Answer 11

chronic exposure of dental hard tissues to acidic substances
- can be extrinsic or intrinsic

Question 12

tooth erosion - early stage

Answer 12

early stages:
- enamel surface affected
- loss of surface detail
- surfaces becomes flat and smooth
- typically bilateral, concave lesions without chalky appearance of bacterial acid decalcification

Question 13

tooth erosion - later stages signs

Answer 13

late stages
- dentine becomes exposed
- wear of dentine leads to ‘cupping’ of incisal edges of anteriors and occlusal surfaces of molars

Question 14

severity and position of tooth erosion depends on….

Answer 14

source, type and frequency of acid exposure

Question 15

erosion - signs

Answer 15

increased translucency of incisal edges - can appear dark
base of lesion not in contact with opposing tooth
amalgam and composite restorations sit proud of tooth
no tooth staining present

Question 16

abfraction - define

Answer 16

loss of hard tissue from eccentric occlusal forces leading to compressive and tensile stresses at the cervical fulcrum of the tooth

Question 17

abfraction - features

Answer 17

v shaped tooth loss where tooth is under tension
classically sharp rim at ACJ

Question 18

cevical wear features

Answer 18

probably multifactorial
lesions mainly on buccal surfaces in premolar and molars
linked to overzealous tooth brushing
- patients with this wear pattern often have good OH
likely to be combination of erosion, abrasion and abfraction

Question 19

tooth wear epidemiology

Answer 19

increases with age
most common type of tooth wear in older patients is physiological
increase in prevalence in all age groups over the past decade
- greater relative increase amongst young adults and children
- can be considered pathological

Question 20

tooth wear prevalence in adults (2009)

Answer 20

77% adult patients had some wear in anteriors involving dentine
more prevalent in males (70% vs 60%)
15% had moderate wear
- increase from 11% over previous 10 years
2% severe wear
- also increased over 10 years

Question 21

tooth wear prevalence in children (2013)

Answer 21

increasing
>50% 5 year olds exhibit some wear on primary incisors
- increase in wear in primary incisors

Question 22

tooth wear - assessment

Answer 22

• recognise problem is present
• grade its severity
• diagnose likely cause or causes
• monitor progression of the disease

Question 23

grade 0 tooth wear

Answer 23

no loss of enamel surface characteristics

Question 24

grade 1 tooth wear

Answer 24

loss of surface enamel characteristics

Question 25

grade 2 tooth wear

Answer 25

buccal, lingual and occlusal loss of enamel, exposing less than 1/3rd of dentine surface incisal loss of enamel minimal dentine exposure

Question 26

grade 3 tooth wear

Answer 26

buccal, lingual and occlusal loss of enamel, exposing more than a third of the surface incisal loss of enamel substantial dentine exposure

Question 27

grade 4 tooth wear

Answer 27

complete buccal, lingual or occlusal loss of enamel. pulpal exposure or exposure of secondary dentine incisal pulp exposure or exposure of secondary dentine

Question 28

Basic erosive wear examination (BEWE) grades

Answer 28

0 - no erosive wear 1 - initial loss of surface texture 2 - distinct defect; <50% hard tissue loss 3 >50% hard tissue surface area loss

Question 29

BEWE risk levels

Answer 29

none - cumulative score of all sextants no risk = less than or equal to 2 low - 3-8 medium - 9-13 high >14

Question 30

tooth wear - special tests

Answer 30

sensibility testing radiographs articulated study models intra oral photographs salivary analysis diagnostic wax up dietary analysis