The design and development of surgical templates for premolar transplants in adolescents

The aim of designing and fabricating the surgical templates was to assist the surgical component of premolar transplantation, by establishing and replicating the root dimensions of the donor premolar tooth. The correct template could be used to assess the socket preparation (width and depth) prior to placement of the transplant in the recipient site, obviating the need to repeatedly try the donor tooth for fit at the recipient site, thereby minimising trauma to the periodontal ligament of the donor tooth. Seventy-five mandibular premolars and 50 maxillary second premolars were selected with varying stages of root development. All teeth had been extracted for orthodontic reasons. The root was measured for its length (maxL) and maximum (maxW) and minimum width (minW) with digital callipers from standardised reference points. These measurements were then used in the design of premolar transplant templates. The mean measurements for second maxillary premolars were maxL 14.6 mm (± 1.7), maxW 8.3 mm (± 0.5) and minW 4.9 (± 0.3). The mean measurements for mandibular premolars were maxL 14.8 (± 1.6), maxW 7.4 (± 0.6) and minW 5.3 (± 0.5). From these measurements, a range of maxillary second premolar and mandibular premolar templates have been fabricated. These figures also inform the multidisciplinary planning process for the space requirements at the donor site prior to transplantation.