Immunology, Microbiology, and Virology Following Placement of NobelPerfect™ Scalloped Dental Implants: Analysis of a Case Series

Abstract

Cytokine-microbiology-virology monitoring after implant placement may help to develop profiles of variables that can help to explain interaction between the immune system and alveolar bone. Descriptive information at the molecular and cellular levels after implant placement is important in the emerging field of osteoimmunology and may help to formulate hypotheses and intervention strategies in periodontology and implantology. The purpose of this study was to determine the presence or absence of selected cytokines in association with periodontopathogens and human cytomegalovirus (HCMV) after placement of dental implants. Charts of seven consecutive patients with 19 NobelPerfect (Nobel Biocare, Yorba Linda, CA, USA) implants were reviewed for crevicular fluid sample outcomes. Anaerobic culture determined periodontopathogens 2 to 5 days, 3 and 6 months postimplant insertion. At 3, 6, and 12 months, real-time reverse transcriptase-polymerase chain reaction (RT-PCR) was performed to detect active HCMV, interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (INF-gamma). Four of five, and six of seven patients harbored no periodontopathogens at 3- or 6-month intervals, respectively. In spite of absence of a bacterial challenge, IL-1beta and TNF-alpha activity was significant. INF-gamma was not detected, and HCMV was present at one time interval only. TNF-alpha is produced mainly in the early stages of acute inflammation, and high levels of this cytokine at 3 and 6 months postimplant placement may be related to a repetitive acute-phase inflammatory response. Lack of INF-gamma and a high cytokine presence without significant corresponding periopathogens or viruses raise a concern that inflammation and, thus, inflammatory bone destruction, is possible outside of these variables. Inflammation and bone loss around this same group of scalloped implants, reported by our previous study, may have been initiated by local factors, such as particular implant design features.