Permanent mandibular protostylid: A rare developmental anomaly and its overview

Developmental malformations of the teeth might result in alterations of their size, shape, and structure. An accessory cusp is a developmental alteration to the shape of the teeth and is more commonly found in anterior teeth, and its occurrence in permanent molars is quite rare. Accessory cusps occurring in permanent mandibular molars are termed as protostylids. Although they do not pose any significant problem with respect to the function and occlusion, it is of tremendous importance in forensic odontology. This case report presents a rare finding of protostylid on the permanent mandibular molar, and its clinical implications are illustrated.

Implant crest module: A review of biomechanical considerations.

The success of dental implants has long been established through various studies with a particular emphasis laid on an implant design. Crest module is that portion of a two-piece metal dental implant, designed to hold the prosthetic components in place and to create a transition zone to the load bearing implant body. Its design, position in relation to the alveolar crest, and an abutment implant interface makes us believe that, it has a major role in integration to both hard and soft tissues. Unfortunately, in most clinical conditions, early tissue breakdown leading to soft tissue and hard tissue loss begins at this region. Early crestal bone loss is usually highest during the first year after placement ranging from 0.9 to 1.6mm and averaged 0.05-0.13mm in the subsequent years . Various hypotheses have been stated to reason it however, none has been proved convincingly. In light of this, various attempts have been made to overcome this undesirable bone loss, by varying an implant design, the position, surgical protocol, and the prosthetic options. Irrespective of an implant system and designs that are used, crestal bone loss of up to the first thread is often observed. The purpose of this review is to look into the various designs and treatment modalities, which have been introduced into the crest module of an implant body to achieve the best biomechanical and esthetic result.