Comparison of bacterial colonization of implant abutment internal recess in internal hex and conical connection implants: An in vivo prospective study.

AIM

Microbial assessment of internal recess of two different internal implant connections in an in vivo study.

STUDY SETTINGS AND DESIGN

This randomized, in vivo study included 40 patients requiring mandibular single-tooth implant-supported prostheses, allocated into two equal groups based on implant connection design.

MATERIALS AND METHODS

Group Internal Hex (IH) and group Conical Connection (CC) received implants with IH and CC, respectively. On the day of prosthetic loading, peri-implant sulcular fluid (PISF) sample was collected and stored. PISF samples were recollected after 3 months. Subsequently, the screw access hole was exposed, and the abutment screw was removed. Implant-abutment recess was washed with saline, lavage was sent for microbiological assay. The abutment screw and crown were restored. PISF was analyzed for interleukin-6 (IL-6).

STATISTICAL ANALYSIS USED

For nonparametric values Chi square test and for parametric values t-test was used to analyse the data.

RESULTS

No implant failure or patient fallout was observed. In Group IH, 17 out of 20 samples were positive for aerobic viz-a-viz 7 samples from Group CC; P = 0.001. For anaerobic bacteria, similar results were obtained with a number of positive samples 19 as compared to 6 in respective groups; P = 0.00002. IL-6 values did not differ significantly from baseline to 3 months in either group.

CONCLUSION

Within the limitations of the study, results show higher bacterial contamination of implant recess in IH than CC. However, the bacterial load had an insignificant contribution to IL-6 levels in PISF of the patients of either group in this time period.