Attrition

0 = cuspal 1 = no cusps 2 =

= Attrition Attrition may be defined as the physiological wearing away of a tooth surface as a result of tooth-to-tooth contact as in mastication. This occurs only on the occlusal/incisal and proximal surfaces of teeth, not on other surfaces.

The first clinical manifestation of attrition may be the appearance of a small polished facet on a cusp tip or ridge or a slight flattening of the incisal edge.

Because of the slight mobility of the teeth in their sockets, a manifestation of the resiliency of the periodontal ligament, similar facets occur at the contact points on the proximal surfaces of the teeth. As the person becomes older and the wear continues, there is a gradual reduction in cusp height and consequent flattening of the occlusal inclined planes. There is also shortening of the length of the dental arch due to reduction in the mesiodistal diameters of the teeth through proximal attrition

Advanced attrition, in which the enamel has been completely worn away in one or more areas, sometimes results in an extrinsic yellow or brown staining of the exposed dentin from food or tobacco (Figures 21.1 A and B). Provided there is no premature loss of the teeth, attrition may progress to the point of complete loss of cuspal interdigitation. In some cases, the teeth may be worn down nearly to the gingiva, but this extreme degree is unusual even in elderly persons

The exposure of dentinal tubules and the subsequent irritation of odontoblastic processes result in formation of secondary dentin pulpal to the primary dentin and this serves as an aid to protect the pulp from further injury. The rate of secondary dentin deposition is usually sufficient to preclude the possibility of pulp exposure through attrition alone. Sometimes, as the teeth wear down by attrition, little tendrils of pulp horn remain and are exposed to the oral cavity. These can be seen only when the tooth is examined carefully under a magnifying lens.

Definition. Attrition is the mechanical wear of the incisal or occlusal surface as a result of functional or parafunctional movements of the mandible (tooth-to-tooth contacts) (Fig. 20.1E). Attrition also includes proximal surface wear at the contact area because of physiologic tooth movement. Etiology If significant abnormal attrition is present, the patient’s functional movements should be evaluated, and inquiry needs to be made about any habits creating this problem, such as tooth grinding, or bruxism, usually resulting from: I. Stress II. Airway issues III. Sleep apnoea

Clinical Features I. In some older patients, the enamel of the cusp tips (or incisal edges) is worn off, resulting in cupped-out areas because the exposed, softer dentin wears faster than the surrounding enamel. II. Sometimes, these areas are an annoyance because of food retention or the presence of peripheral, ragged and sharp enamel edges (Fig. 20.3). III. Heavy occlusal loading from clenching may result in the presence of ‘craze lines’ which are limited to enamel (i.e. do not progress through the DEJ into dentin; Fig. 20.1F). Craze lines are not sensitive and do not require treatment but may be evidence of excessive masticatory muscle activity. IV. Slowing such wear by appropriate restorative treatment is indicated. The sharp edges can result in tongue or cheek biting; rounding these edges does not completely resolve the problem but does improve comfort.

== differential diagnosis fracture