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Posterior restorations--a clinical view.

This paper examines the state-of-the-art in the direct restoration of posterior teeth. The existing paradigms for the management of caries are questioned and some existing methods of cavity preparation are reviewed. Dental restorations need to be durable but able to adapt to a changing environment brought about by wear of the adjacent tooth substance and by fatigue processes within the tooth itself. The wear of restorative materials needs to be matched to that of the tooth, otherwise differential loss of either the restorative material or the enamel may destabilize the occlusion. Esthetic instability due to natural darkening of the tooth with age, punctuated by clinical intervention with bleaching procedures, adds a further dimension to the concept of a permanent restoration. Clinical methods that minimize the disruptive effects of dental restorations upon the remaining tooth structure are a continuing challenge.