ETIOLOGY
What causes exaggerated incisal wear? Usually the pattern is multi-factorial, involving one or more of the factors to be described. Restoration of the teeth remains the same, regardless of etiology, but clinical management and follow-up must attempt to control etiological factors.
Age itself is the first factor: in the typical attrition- related lesion, the patient is in the 4th to 5th decade of life. Normal wear breaks through the enamel into dentin on one or more teeth in the upper or lower incisors.
OCCLUSAL FACTORS
Opposing porcelain both in crowns and dentures often accelerate wear on individual teeth.
Loss of posterior teeth, shifts excess function onto anterior teeth. Tilted molars often create inclined planes which may contribute an anterior thrust to occlusion.
Parafunction: Bruxism, clenching
Occlusal disharmony plunger cusps forcing excursive paths into narrow functional envelopes, accelerating wear in specific anterior zones
Tooth malposition– rotations or crowding which incur excessive the contact time of incisors.
Deep overbite
Excessive Curve of Spee as in the model below
Canted maxilla
Worn cuspids which no longer disclude the anteriors
ACIDITY
- Sleep apnea
- gastro-oesophageal reflux or GERD
- Bulimia
- Excessive use of low-pH bottled drinks
- acidic fruit juices
- Vinegar exposure as in salad dressings
- acidic wine
- Street drug use such as crack cocaine and methedrine
FAMILIAL GENETICS
- Some families have a trend towards anterior destruction for no obvious reason. Working in a small community, as I do, I see extended families spanning three generations. In some family lines, occlusions are all flattened and worn into the dentin by early middle age. Unfortunate dental genes!
UNTREATED INCISOR FRACTURE
If a fractured incisor in early life is untreated, the tooth passively erupts and wear is accelerated relative to the adjacent teeth because no enamel is present on the fractured tooth.
INCISAL ATTRITION IN YOUNG PATIENTS
While Incisal attrition is most commonly seen in older patients, young patients may demonstrate premature wear, due to
- Parafunction
- Poor posterior occlusion
- Exaggerated Curve of Spee as seen in photo above
- Acid dissolution from low pH beverages such as sports drinks containing citric acid, and caffeine bombs high in phosphoric acid.
- Abrasion from opposing porcelain in ceramic-metal crowns placed early in life.