hard tooth tissue reduction

hard tooth tissues

the mineralized, structural components that protect the tooth’s inner soft tissue

attrition

the physiologic wearing away of a tooth as a result of tooth-to-tooth contact, as in mastication, occurring only on the occlusal, incisal, and proximal surfaces

attrition

is a process in which tooth tissue is removed as a result of opposing tooth surfaces contacting during function or parafunction

proximal areas, supporitng cusps, guiding surfaces

attrition direct contact occurs at —, on —, and on — during empty grinding movements

mastication, fibrous diet, tobacco and betelnut chewing, bruxism or night grinding

etiology of attrition

58 psi

bite force studies

• force during chewing

68 psi

bite force studies

• during swallowing

85 psi

bite force studies

• biting on the anteriors

150-175 psi

bite force studies

• biting on the posteriors

70-900 psi

bite force studies

• during sleep

anatomical involvement, degree of anatomical involvement

classification of attrition

incisal attrition

anatomical involvement in attrition

• due to lack of supporting occlusion as in the absence of posterior teeth, so that the surface of lower anterior teeth is worn obliquely

occlusal attrition

anatomical involvement in attrition

• due to functional mastication (occurs on posteriors)

proximal attrition

anatomical involvement in attrition

• due to friction caused by tooth movement during mastication

• on tooth with very tight proximal contacts

malocclusion, rotated teeth, parafunctional habits, loss of posterior support

there is an abnormal contact and excessive friction at specific points between teeth

1st degree

degree of anatomical involvement in attrition

• cusp are worn out flat, only the enamel without exposing the dentin

• asymptomatic

2nd degree

degree of anatomical involvement in attrition

• tooth is worn out

• enamel and primary dentin are exposed

3rd degree

degree of anatomical involvement in attrition

• ring of secondary dentin is visible

• enamel, primary+secondary dentin are exposed

3rd degree

degree of anatomical involvement in attrition

• dangerous as secondary dentin is thin, so this means it is very close to 4th degree

3rd degree

degree of anatomical involvement in attrition

• already symptomatic or sensitive due to thin protection of pulp left

• dark yellow appearance

4th degree

degree of anatomical involvement in attrition

• pulpal involvement

• enamel, primary + secondary dentin + pulp are exposed

abrasion

this is used to indicate the wear that occurs on any part of the tooth due to friction of a foreign body with tooth tissues or due to mechanical factor

brushing

abrasion is the pathologic wearing away of the tooth substance by —, and other mechanical causes

brushing of teeth horizontally

etiology of abrasion

• cervical wear with gingival recession caused by gritty substances or abrasive paste and hard bristles of toothbrush

dental floss silk

etiology of abrasion

• habitually and vigorously used produces narrow grooves on proximal surfaces

pipe smoking

etiology of abrasion

• when stem is habitually held in position causes a deep groove to be worn on the incisal and occlusal surfaces of the teeth concerned

obvious occupational habits

etiology of abrasion

• could be a tailor who cuts thread with their teeth or hair stylist who open hair pin with their teeth

habitual and improper use of toothpicks

etiology of abrasion

• produce proximal abrasions on exposed root surfaces

mutilation of teeth with grinding stone

etiology of abrasion

• dentist / clinical fault

brushing of teeth horizontally, dental floss silk, pipe smoking, obvious occupational habits, habitual and improper use of toothpicks, mutilation of teeth with grinding stone, nail biting

etiology of abrasion

abraded, notched

signs of abrasion

• tooth biting surfaces — and —

c-shaped groove

feature of abrasion

• — is formed on cervical margins of the teeth in horizontal tooth brushing technique

hard, highly polished

feature of abrasion

• exposed dentin is — and —

discolored yellowish-brown

feature of abrasion

• when caused by pipe smoking, the worn surface is — due to tobacco stain

formation of sclerosed dentin, dead tracts in dentin, reparative dentin

histopathology of abrasion

prevention, restoration, fluoride applications, tooth-colored bonding, correct the faulty habits

treatment of abrasion

once the gums begin to recede, root surfaces become exposed and sensitivity to hot and cold temperatures soon follow

prognosis of abrasion

abfraction

notches on teeth that develop along the gum line as a result of mechanical stress due to excessive pressure when teeth bite together

flexure

abfraction create a repeated tooth — with failure of enamel and dentin at a location away from the point of loading

tooth bending forces at cervical, tensile stress, flexure

etiology of abfraction

deep, narrow, v-shaped, lesions are subgingival affects facial surfaces of premolars and molars

clinical features of abfraction

eliminate the defective occlusal contacts, restoration of the cervical defect with mechanical retention or by a periodontal reattachment procedure

management of abfraction

this term is used to indicate the wear occurring on tooth surfaces due to chemicals

acid

erosion is usually associated with — leading to dissolution of inorganic substances aided by mechanical factor

chemical or acid disintegration of the tooth surface

etiology of erosion

extrinsic, intrinsic

erosion-producing acids can be either — or — in origin

intrinsic causes

type of erosion-producing acids

• acid source inside the body

gastric acid, psychologic disorders

acid sources inside the body for erosion are —

extrinsic acids

type of erosion-producing acids

• source is outside of the body

acidic beverages, foods, medications, dietary acids

acid source outside the body for erosion are —

occupational, recreational exposure

less common sources of extrinsic erosive acids are related to — and —

dead tracts in dentin, reparative dentin, degenerative changes in pulp

histopathology of erosion

wedge-shape or disc-shape groove on cervical area, loss of enamel, dentin exposed is sensitive

clinical features of erosion