Peri-Implant Response and Microflora in Organ Transplant Patients 1 Year after Prosthetic Loading: A Prospective Controlled Study

A recent study conducted in humans demonstrated for the first time that bone loss in the immediate period after implant insertion before loading did not significantly differ in organ transplant recipients with respect to normal subjects.The purpose of this study is to evaluate bone and periodontal response and peri-implant microflora in a group of organ-transplanted patients 1 year after prosthetic loading.The study population included 13 consecutive organ-transplanted (11 hearts, two livers) patients and 13 normal (healthy) control subjects who received 29 and 28 submerged dental implants, respectively. Crestal bone level, peri-implant probing depth (PIPD), and bleeding on probing were evaluated at prosthetic loading and after 1 year. Samples for microbiological testing were taken from the subgingival microbiota of each implant 1 year after loading and analyzed with polymerase chain reaction. All samples were examined for the presence of five microorganisms: Treponema denticola, Porphyromonas gingivalis, Prevotella intermedia, Tannarella forsythensis, and Actinobacillus actinomycetemcomitans.A mean bone loss of 0.17 ± 0.10 and 0.20 ± 0.10 mm at 1 year was observed in the group of transplant recipients and in controls, respectively (N.S.). Similar results were obtained considering PIPD changes at 1 year (respectively 0.06 ± 0.71 mm in transplants vs 0.11 ± 0.74 mm in controls). Detection frequencies of pathogens were not statistically different between normal and transplanted patients.The present pilot study seems to indicate that bone and periodontal response and microbiological status around submerged dental implants in immunocompromised organ-transplanted patients do not differ 1 year after loading from those observed in control patients and that this particular population of patients may be successfully rehabilitated with dental implants.