Part III: Crystalline Fluorapatite-Coated Hydroxyapatite; Potential Use as a Bacteriostatic Agent for Both Pre-Implant Cases and Retreatment of Infected Implant Sites: A Report of 4 Cases

Abstract

Four cases of peri-implant bone loss associated with undiagnosed necrotic pulps of adjacent teeth are reported. In two cases, bone was obliterated along sinus tracts (fistulas) that coursed between the implant and adjacent tooth. Endodontic treatment was completed on the adjacent teeth concurrent with periapical surgery to seal the tooth apex. The sinus tract (fistula) was excised, and the implant plus tooth surfaces were treated with a combination of concentrated citric acid and 4.3% sodium fluoride solutions. The third case involved peri-implant surgery with endodontic treatment on the adjacent tooth. A fourth case represented an infected socket augmentation which was surgically treated, augmented with microcrystalline fluorapatite in the range of a 300 µm to 400 µm cluster, and allowed to heal for 4 months followed by a trephine bone biopsy and subsequent analysis for bone growth around the fluoridated nonceramic microcrystalline hydroxyapatite (HA). An augmentation procedure employing fluoridated of resorbable HA was then completed. Histologic analysis showed healthy bone regeneration suggesting that therapeutic fluoride treatment and resultant fluorapatite were helpful in inhibiting reinfection following surgical treatment. All 4 infected implant sites were successfully managed and retained using the aforementioned treatment schemes, and there was no evidence of posttreatment infection in any of the 4 cases. It is proposed that fluoride treatment, through the use of 4.3% sodium fluoride and/or fluoridated hydroxyapatite (fluorapatite), shows promise as an adjunctive treatment component in inhibiting peri-implant infection and reinfection when managing ailing or failing implants.