Effect of additional surgical procedures on root development of transplanted immature third molars.

The aim of this investigation was to determine the influence of additional surgical procedures on the root development of transplanted teeth. The study sample consisted of 90 immature third molars transplanted in 88 patients. All transplanted teeth were at root development stages 3 to 4. Free bone autografts were used in 23 cases (bone autograft group), mainly because of vertical atrophy of the alveolar process. A splitting osteotomy of the alveolar process was performed in 25 cases with marked horizontal atrophy (osteotomy group). Forty-two teeth transplanted into a fresh extraction site immediately after extraction of the non-retainable tooth served as controls. At root development stage 3, significant differences were determined between the osteotomy and the control groups in final root length (P<0.001) and root length increment (P=0.004). Transplants in the osteotomy group revealed a significantly lower root length increment than transplants in the bone autograft group (P=0.008). No significant intergroup differences were observed at root development stage 4. These results indicate that a splitting osteotomy of the alveolar process has a negative effect on root development of transplanted teeth at earlier developmental stages.

Root development of immature third molars transplanted to surgically created sockets.

PURPOSE: The aim of this study was to compare root development after transplantation of teeth into surgically created sockets or into fresh extraction sites. PATIENTS AND METHODS: The sample consisted of 62 patients with a total of 64 transplanted immature third molars. All transplants were at root development stages 3 to 4. In 22 cases, a new socket was created by means of burs. Forty-two teeth transplanted into a fresh extraction site served as controls. Postoperative root development was determined on intraoral radiographs taken immediately after transplantation and at the final follow-up. For all transplants, extraoral storage time and number of trials were recorded during transplantation. RESULTS: No significant intergroup differences were observed at root development stage 3. In contrast, at root development stage 4 transplantations to surgically created sockets showed a significantly lower final root length (P = .025) and root length increment (P = .038) than transplants in the control group. In addition, a significant correlation was determined in the prepared socket group at developmental stage 4 between root length increment and extraoral storage time (r = -0.910, r(2) = 0.828, P < .001) or number of trials in the recipient socket (r = -0.775, r(2) = 0.601, P < .001). CONCLUSIONS: Teeth at advanced developmental stages transplanted to surgically created sockets show an impaired postoperative root development. A possible explanation might be damage of Hertwig's epithelial root sheath during the transplantation procedure.