Bruxism--a rationale of therapy.

During the past 20 years the prevalence of bruxism and its damaging effects on the periodontium, alveolar bone and teeth have become increasingly apparent. Brux­ ism is defined as “ the inaudible gnashing or audible grinding of teeth or cuspal interferences during unsuspected move­ ments of the mandible.” 1 This pernicious habit affects the dental mechanism in two basic ways. It causes abnormal attrition of the teeth, its most commonly recog­ nized symptom (Fig. 1 ), and it may cause periodontal difficulties with subsequent loosening and migration of teeth (Fig. 2 ). Leof2 maintains that pressure habits are the initial or contributing cause of the majority of periodontal disturbances. In fact, many reconstructions and rehabilita­ tions are damaged by this excessive and abusive habit. Nadler3 classified the causes of bruxism in four groups: 1. Local causes: occlusal traumas, missing teeth, anatomical defects and oc­ clusal disharmonies.