Vertical alveolar ridge distraction with prosthetic treatable distractors: a clinical investigation

Alveolar ridge distraction is a recent and promising technique for ridge augmentation. Since 1997, a new distraction system incorporating a distraction implant has been in use. It can be used for alveolar ridge distraction and is not removed from the alveolar ridge. Upon completion of the distraction, it remains in the alveolar process for later prosthetic treatment. Thirty-five patients were treated with distraction implants for the correction of alveolar ridge deficiency. In 10 patients with atrophy of the mandible or maxilla, 16 patients with severe defects of the alveolar process after trauma, and 9 patients with localized alveolar ridge defects after single tooth loss, alveolar ridge distraction was carried out with the aid of 62 distraction implants. The distraction implants were loaded by prosthetic superstructures 4 to 6 months after distraction. A clinical and radiologic follow-up was carried out. Periotest values were examined, and peri-implant bleeding and probing depth were registered prior to prosthetic treatment and 3, 6, and 9 months after implant loading. In 29 patients, distraction was carried out without complications or problems. Two distraction implants were lost. In 2 patients distraction was discontinued because of ankylosis of the distraction segment. In 1 patient the alveolar ridge was overcorrected, and another patient experienced a persisting hypoesthesia of the lip. For 5% of the implants, pathologic probing depth of more than 3 mm and sulcus bleeding were registered prior to prosthetic treatment. These observations decreased during the next 9 months. Periotest values were normal before the start of prosthetic treatment. There was a decrease in the Periotest values, thus an increase in implant stability, during the following 9 months. It was concluded that alveolar ridge distraction using distraction implants can be a successful technique for alveolar ridge augmentation with a low rate of complication. Acceptable esthetic and functional results can be achieved by this atraumatic technique of surgery and distraction.