5.4. Dento-alveolar reconstruction with coral-derived granules

In study V the 48 augmentation sites of coral granules in alveolar sockets healed well with few significant complications. In Group One, where tooth-loss was secondary to trauma in the anterior maxilla, the coral granules restored the dimensions of the alveolar ridges temporarily. However, over the course of follow-up only 3 of 17 sites (17.6%) grafted with coral granules yielded sufficient bony support for the placement of an osseointegrated dental implant without using a revisional bone graft. In the 14 sites where the coral had failed to maintain the volume of the alveolar process, a revisional bone graft provided enough osseous support for the successful future placement of an osseointegrated dental implant in all the failed cases. In Group Two, in the posterior maxilla and mandible, where tooth-loss was due to the elective removal of ankylosed primary molars, 29 of 31 (93.5%) of sites were able to support the successful placement of an osseointegrated dental implant without the use of a bone graft (Table 11). This difference between Groups One and Two was found to be statistically significant using a Chi-square test (p < 0.001).

One case of infection with abscess and fistula formation, and radiographic signs of resorption of coral granules was observed in the anterior maxilla. The infection originated from a fractured root tip, and necessitated removal of the coral granules. No other complications as seen in previous studies, such as wound dehiscence due to inflammation from coral granules inadvertently left in the superficial layers of the wound were observed during the 3 to 8 year follow-up period in this study.

A total of 32 dental implants were placed into coral granule-derived bone, which appeared to be of sufficient quantity to support an osseointegrated implant. Two implant fixtures failed to osseointegrate, one in the anterior maxilla and one in the posterior mandible. The 2 failed sites (6.3%) were subsequently grafted with autologous bone, which in both cases, resulted in successful osseointegration. All the other 30 dental implants (93.7%), placed in coral granule-generated bone are still currently in function from 3 to 7 years after their placement. They are followed annually on an ongoing basis. In those alveoli where the coral granules failed to provide sufficient bone to place an osseointegrated dental implant, a secondary or revisional bone graft was placed which resulted in later successful placement of dental implants at all the grafted sites.