Tooth transplantation is a surgical process involving the transfer of a tooth from its dental socket to the socket of an extracted tooth or to a site in the jaw where there is no tooth. A tooth can be transplanted within the same jaw or from one jaw to another.
INDICATIONS FOR TOOTH TRANSPLANTATION
Tooth transplantation is carried out in the presence of the following tooth and jaw issues:
WHEN AND HOW IS TOOTH TRANSPLANTATION PERFORMED?
Tooth transplantation is most commonly done in cases of premature loss of first or second molars. This is done through the surgical extraction of unerupted wisdom teeth, which can then be used and processed for transplantation to the edentulous site. Donor teeth can also include premolars and supernumerary teeth.
In younger individuals, tooth transplantation usually involves the transplantation of the tooth bud, primarily the bud of a wisdom tooth to the site of an extracted permanent molar, or the bud of a lower premolar to the site of an extracted incisor in the upper jaw. This allows for the development of a vital tooth with normal circulation and a supporting structure.
Radiography showing tooth 16 with periapical changes (black arrow). Tooth 18 with unfinished root growth is indicated for transplantation instead of tooth 16.
SURGICAL TECHNIQUE
The surgical technique depends on the indications and timing of the transplantation. In principle, transplantation can be performed in one visit or in two visits with a gap of 14-21 days.
The first phase involves the extraction of the diseased tooth, the preparation of the alveolus to remove any septa, and the expansion of its capacity.
The second phase is carried out after 14–21 days. Once granulation tissue rich in blood vessels forms in the alveolus, the impacted wisdom tooth is pressed into it, following the creation of a bed in the granulation tissue through simple cutting or excision of the central part. The transplanted tooth is pressed into the granulation tissue, and the gingiva around it is fixed with two sutures.
Radiography shows tooth 18 transplanted to the location of tooth 16, where the root has fully formed, ensuring that the tooth remains vital (white arrow).
After transplantation, a stable connection forms between the tooth root and newly developed bone tissue. This allows the transplanted teeth to function like natural teeth, providing conditions for proprioception, development of the dentofacial skeleton, improved aesthetics, and preservation of the integrity of the dental arch.
POST-TRANSPLANTATION PROCEDURES
In individuals who have undergone transplantation with fully developed roots, endodontic therapy, including trepanation of the tooth, widening of the root canals, and filling with calcium hydroxide paste, is performed after about 14 days. This paste is removed after a few months and replaced with a definitive filling.
For children who have lost a central incisor in the upper jaw and where a premolar from the lower jaw has been transplanted at a 90-degree rotation, the crown is reshaped into the form of an incisor. If such transplantation is performed on adults with fully developed roots, the previously described endodontic procedure is first carried out, followed by reshaping of the crown
DIFFICULTIES AND COMPLICATIONS
Despite the best technique, experience, and knowledge, sometimes the impacted wisdom tooth is bulky, and the alveolus of the extracted tooth is not wide enough to accommodate the transplant. The shape and arrangement of the roots of the wisdom tooth, in a smaller number of cases, may make the tooth unsuitable for transplantation. Occasionally, it may not be possible to extract the wisdom tooth entirely, leading to discontinuation of the procedure. Infection and rejection of the transplant are also possible, although this occurs very rarely. International studies have shown a success rate of over 90% over a period of 17-41 years.