Autotransplantation of human premolars. A clinical and radiographic study of 100 teeth

Autogenous free tooth transplantation in man by a 2-stage operation technique. A longitudinal intra-individual radiographic assessment

Insufficient nutrition to the root surface of autotransplanted mature human teeth after transplantation could be an explanation for the high rates of complications such as root resorption and loss of the tooth transplant. Insufficient nutrition is suggested as being due to the distance between the recipient site tissue and the root surface, and the presence of a blood-clot between the tissues. Improved nutrition could be achieved by transplanting into contact with the vascularised connective tissue of a healing wound. To test this hypothesis, a series of human teeth with fully developed roots were autotransplanted to recipient sites prepared and left to heal for 14 days before transplantation. This study is a follow-up of 57 transplants with a minimum observation time of 1 year. Periodic radiographic examinations of the teeth were performed up to 5 years after transplantation. The results presented, showed a lower incidence of root resorption and extractions than previously reported for teeth with fully developed roots.

Allotransplantation and autotransplantation of mature teeth in monkeys: the influence of endodontic treatment

This study investigated the effect of endodontic treatment on root resorption of autotransplanted and allotransplanted mature teeth in unmatched monkeys. The material comprised 40 mature maxillary central incisors in 20 green Vervet monkeys (Cercopithecus aethiops). Teeth were either allotransplanted or autotransplanted in pairs of monkeys matched only for the size of the root. Endodontic treatment was performed at random peroperatively with gutta percha and Kerr sealer in 10 of each of the 20 autografts and 20 allografts. The extra-alveolar period was 18 minutes in all groups. Histometric analysis, which included registration of surface and inflammatory and replacement resorption (ankylosis), was done on serial sections of the grafts 8 weeks after transplantation. Endodontic treatment almost completely reduced inflammatory resorption in both allotransplanted and autotransplanted mature teeth (p less than 0.01). Peroperative endodontics elicited a small increase in ankylosis in autografts. In allografts, it unmasked a high amount of ankylosis, presumably primarily due to alloimmune reactions against the donor periodontal ligament, leaving only a small portion of normal ligament almost exclusively located along the cervical region of the root surface. Downgrowth of periodontal pocket epithelium was limited in all groups.

Removal of third molar germs. Study of complications

Enucleation of the third molar germ has been discussed as an alternative to extractions of premolars in borderline cases of crowding in the mandibular arch. A total of 86 patients in the age group 8-17 years had their mandibular third molar germs removed bilaterally by the same procedure in local anaesthesia. Intramuscular injection of 6 mg Celeston-Chronodose R was given postoperatively. We experienced that the postoperative complications were few and the psychological reactions were acceptable.

Allotransplantation of human teeth. A retrospective study of 73 transplantations over a period of 28 years

An assessment was made of the postoperative fate of 73 allotransplanted human teeth carried out by 3 surgeons between 1956 and 1980 to determine the clinical and radiographical course of immunogenetically unmatched allotransplanted human teeth. The mean ages of recipients and donors were 34.1 and 15.2 years, respectively; 47 of the grafts had incomplete root-formation at time of transplantation. Mean observation period was 7.8 years with a maximum of 28 years. The study was terminated December 1985. The mean functional time of the grafts (function of graft without symptoms) was 6.8 years (max. 28.5 years). No signs of pulpal survival were found in any graft. Root resorption was found in 91.6% of grafts within a mean of 8.8 months after transplantation, causing a high frequency of graft loss within the first 2 years (34.1%). Recipients older than 45 years of age retained the grafts significantly longer than young patients. The major causes of graft loss were replacement (60.3%) and inflammatory resorption (24.4%). Graft loss due to marginal periodontitis was minor (2.7%). Inflammatory resorption, which was found more frequent in young recipients (P = 0.02), usually caused rapid rejection, whereas the survival time after ankylosis was significantly longer. In conclusion, no clinical or radiographical evidence of long-term survival of the pulpal or periodontal tissues of the unmatched allografts were found. However, despite a progressing replacement resorption frequently present, the allografts seem to function clinically sufficient, symptomless and often with clinically normal gingival condition for many years. Increasing age of the recipient at time of transplantation significantly increased the function time of the graft. Younger recipients showed more inflammatory resorption of the grafts.

Regional control by the dental follicle of alterations in alveolar bone metabolism during tooth eruption

Tooth eruption is a localized, bilaterally symmetrical series of events which involves resorption and formation of alveolar bone on opposite sides of the tooth and requires the presence of the dental follicle. We examined the effect on eruption of selective surgical removal of parts of the follicle. Removal of either the basal or coronal halves of the follicle prevented eruption. Bone resorption and formation of an eruption pathway did not occur after removal of the coronal part of the follicle and bone formation did not occur after removal of the basal part of the follicle. Exposure and incisions of the follicle had no effect on eruption. We interpret these data to mean that the polarized resorption and formation of alveolar bone that occur around a tooth during eruption are regulated by the adjacent parts of the dental follicle.

Transalveolar transplantation of maxillary canines. An alternative to orthodontic treatment in adult patients

Transalveolar transplantation of 31 maxillary canines in 26 patients was performed. Fixed orthodontic appliances were used for fixation for 6 to 8 weeks. All the transplanted teeth were firmly affixed in the new positions 3 to 6 months postoperatively. Complete bone regeneration and an attached gingiva with a stippled surface buccally and a normal pocket depth were observed 1 to 2 years postoperatively. These positive treatment results indicate that transalveolar transplantation is a useful alternative in the treatment of impacted maxillary canines in selected patients.

Influence of orthodontic treatment on root development of autotransplanted premolars

The aim of this study was to clarify whether orthodontic movement of autotransplanted premolars will affect the final root length of the transplants. A group of 29 autotransplanted premolars that had been orthodontically treated was compared with a group of 30 autotransplanted premolars that had not been orthodontically treated. Contralateral teeth in both groups served as controls. The root lengths of the transplants as well as the controls were measured on the radiographs immediately after transplantation and also after orthodontic treatment and complete root formation. The results demonstrated that there was no statistically significant difference between the original and final root lengths of the transplants in the two samples or between the contralateral teeth. The autotransplantation of the premolars resulted in an average shortening of 1 to 2 mm compared to the contralateral control teeth. Futhermore, orthodontic movement of the transplants appeared to have a tendency to shorten the final root length.