Bone Response to Submerged Implants in Organ Transplant Patients: A Prospective Controlled Study

Purpose: To evaluate the short-term outcome of dental implant therapy in a group of organ transplanted patients as compared with a control group. Materials and methods: The study population included 10 consecutive organ transplanted (8 hearts, 2 livers) patients and 10 consecutive normal (healthy) subjects as controls, who received 20 and 12 submerged dental implants (NobelReplace Tapered Groovy, NR; Nobel Biocare AB) respectively. Two films were taken of all patients at both baseline and after a healing period of 3 months. All radiographs were twice (15 days apart) blindly analyzed by two independent trained radiologists. Crestal bone level (CBL) is defined as the perpendicular distance from the reference point on the implant to the first visible apical bone-to-implant contact. Results. At the 3-month follow up visit no implant showed even a minimal self-exposure of the cover screw. CBL increased in both groups without any significant difference between the groups (CBL increased from 0.08 mm ± 0.09 to 0.28 mm ± 0.20 in organ transplants and from 0.11 mm ± 0.16 to 0.42 mm ± 0.32 in controls). Multiple ANOVA showed that the mean bone loss of 0.21 mm ± 0.18 observed in the group of transplants was not statistically different from that (0.32 mm ± 0.25) found in the control group, and was not influenced by any of all variables considered. Conclusions: The present pilot study seems to indicate that bone response around submerged dental implants in immunocompromised organ-transplants patients does not differ from that observed in control patients and that this peculiar population of patients may be successfully rehabilitated with dental implants.