2 Flashcards
Chipping of the incisal edge in maxillary anterior teeth is usually a sign of
Erosion
Cupping of the incisal edges/cusps is due to
Acid erosion- acid dissolves cusp tip, breaks though the enamel gets into the dentine, and dentine resolves more rapidly than enamel so then you get the cups
Management - not enormous need for restoration, maybe plaque control and fluoride
Definition of erosion
Progressive loss of tooth substance by chemical processes that do not involve bacterial action
What is perimolysis
Acidic erosion of the teeth as a result of chronic acid regurgation
Attrition
Due to physiological wearing of teeth
Lesions are on occlusal and incisal contacting surfaces
Early signs- polished facet on a cusp, slight flattering of an incisal edge
Advanced- reduction in cusp height, flattering of occlusal inclined planes and shortening of the incisors and canine teeth
Abrasion
Physical wear of teeth independent of occlusion- due to foreign objects repeatedly contacting the tooth
Most common teeth affected- labial/buccal aspect on canine, premolar teeth
V shaped or rounded lesions, sharp margin at enamel edge
Notching of incisal edges
Causes: tooth brushing, pipe smoking, nails…
Erosion
Early stages: enamel surface is affected and loss of surface detail: bilateral, concave lesions translucent incisal edges
Advanced: dentine expose causing cupping of the occlusal surfaces
Position and severity depends on the source, type and frequency of exposure
Base of the lesion not in contact with the opposing tooth
No tooth staining if rapidly progressing
Extrinsic erosion: drinks of less than 2.5 pH
Intrinsic erosion: stomach acid of less than 1 pH and it much more destructive than extrinsic
Inner enamel- rich in acid- soluble ions, and dissolves preferentially, high prismatic structure, easily attacked by acid
Outer enamel- rich in ions that resist acid attack , is more amorphous so more resistant to acid
Abfraction
Loss of hard tissue from eccentric occlusal forces leading to compressive and tensile stresses at the cervical fulcrum areas of the tooth
Pathological loss due to biomechanical loading forces that lead to flexure and failure of the enamel and dentine at the location away from the loading.
Causes disruption of ordered crystalline structure of the enamel and dentine
V shaped loss- sharp rim at the CEJ
PT with erosion due to vomiting
Advices:
Freshen up mouth using bicarbonate after vomiting
Rinse the mouth with water after brushing
Don’t brush your teeth after vomiting
Acid reflux causing intrinsic erosion
Prevention:
Elevation of soft palate
Sides of the tongue contacting posterior pharyngeal wall
Upper oesophageal sphincter (preventing reflux from oesophagus into pharynx)
Lower oesophageal sphincter (preventing reflux from stomach into oesophagus
Extrinsic erosion
Medications and OH products
-vitamin c (absorbic acid) chewable tablets can cause extensive destruction
- iron preparation (acidic) usually taken during pregnancy
- some mouthwashes and artificial saliva products can be acidic
Asthma inhalers can have low pH
Why is the enamel around the gingival margin less affected?
Due to buffering effect of the gingival crevicular fluid with pH between 7.5 and 8.7
Titrable acidity
It means the amount of hydrogen ions available for erosive attack rather than pH
It is more important than pH of the diet
Attrition
Mechanical wear resulting from chewing or parafunction limited to the contacting surfaces of teeth (usually on opposing tooth as well, seen as facets)
No chipping of incisal edges
Flat surfaces on worn tooth
Can be due to restoration causing wear as it is stronger material
Abrasiveness of dental material
Greatest to least abrasive
Unglazed porcelain, glazed porcelain, cast chrome cobalt, cast nickel chrome, cast gold, composite resin, GIC, acrylic resin
