Endodontic Treatment of Teeth Induces Retrograde Peri-Implantitis
A study was performed in China and published recently in The Clinical Oral Implants Research, Vol.20 No.12 pp1326-1332.This study aimed to determine the incidence of retrograde peri-implantitis in implants placed adjacent to teeth that have undergone successful endodontic treatment.
Material and Methods:
128 patients each had a single Straumann SLA implant placed, 65 of which were in the mandible, with 63 in the maxilla. Smokers, bruxers, or patients with type IV bone or those who needed augmentation were excluded. The reason for tooth loss, as well as the healing period before implant placement were recorded. Endodontic treatment or re-treatment of adjacent teeth had been completed at the study center using conventional techniques. Implant stability quotients (ISQ) were measured using resonance frequency analysis at placement, 1 and 3 months, using the Ostell device (Integration Diagnostics). Standardized radiographs were analyzed by a single examiner to measure the distance between the implant and adjacent root apex. All data was subject to statistical analysis to determine the significance of time from endodontic treatment to implantation, as well as physical distance from implant to tooth apex.
Results:
123 of the 128 implants were surviving at the end of the study period, however, 10 implants developed retrograde peri-implantitis, equating to a 92.2% success rate. Six of these affected implants were in the maxilla compared with four in the mandible (NS). In all the retrograde peri-implantitis cases bar one, the adjacent teeth were non-vital. Multiple logistic regression analysis showed that although the mean time from adjacent endodontic therapy to implant placement was 12±10 weeks, this was highly statistically significant at the 95% confidence interval for retrograde peri-implantitis if placement was within 4 weeks. Distances of less than 2mm between root apex and implant, also yielded a higher incidence of retrograde peri-implantitis. ISQ values of affected implants at 3 months compared to those without retrograde peri-implantitis decreased, but this was not statistically significant. Five of the 10 affected implants resulted in removal due to mobility, 4 having been subject to endodontic re-treatment of adjacent teeth and 1 which had undergone surgical treatment to decontaminate and repair the apical damage.
In conclusion, this study clearly demonstrates that increasing the distance between the implant and the adjacent tooth, and increasing the time between endodontic treatment and implant placement, may eliminate the risk of retrograde peri-implantitis.
Reference:
Wei Zhou et al. The Clinical Oral Implants Research, Vol.20 No.12 pp1326-1332
