Radiological evaluation of marginal bone loss at tooth surfaces facing single Brånemark implants.

A radiologic evaluation of marginal bone loss around single implants ad modum Brånemark and their adjacent teeth was performed: 58 adults with 71 fixtures were followed up to 3 years after crown installation. The following factors were considered: age, cause of tooth loss, vertical relation between fixture and teeth, distance between adjacent teeth, distance between fixture and natural tooth, jaw region. Specified distance were measured as well as marginal bone levels around fixtures and tooth surfaces in magnified standardized intraoral radiographs. The results show a loss of marginal bone support at tooth surfaces adjacent to inserted implants during the interval between preoperative examination and crown installation that exceeds the loss during subsequent years. The largest bone loss was observed when implants were placed next to lateral upper incisors. A strong correlation was found between bone loss at adjacent teeth and the horizontal distance fixture-tooth. With decreasing distance the bone loss increased, especially in the upper incisor region. At present it seems difficult to predict which individual or individual condition may have a higher risk for bone loss, due to large intra- and interindividual variation.