[The influence of two implant materials on the growth of three subgingival predominant bacteria].

Objective: Commercially pure titanium and titanium alloy as dental implants have show impressive clinical results. Despite the high success rates, some implants do fail. Compared to those studies on osseointegration of implants, the information pertaining to their failure is little. Further studies on the relationship between implant material and micro-organism are needed. The purpose of this investigation is to study the effect of two commonly used implant materials Titanium (TA2) and Ti-6AI-4V alloy (TC4) on the growth behaviour of three subgingival predominant bacteria Streptococcus sanguis (S. s), Porphyromanus gingivalis (P. g), Fusobacterium nucleatum (F. n) and their mixture.

Methods: Under anaerobic condition, bacterial suspensions of S.s, P.g, F.n and their mixture were incubated together with the two implant materials respectively, setting the same bacterial suspensions as controls. After 2, 7 and 14 days, the bacterial growth amount was assayed by means of clone forming unit (CFU) method. The pH value of the bacterial suspension was determined by pH-Meter.

Results: The results showed that there was no difference in amount of bacterial growth or pH value between TA2 group and TC4 group (P > 0.05). There was also no statistically significant change as to the proportion of individual bacteria in bacterial mixture or the pH value of culture suspension.

Conclusion: Under the condition of this investigation, the two studies implant materials have no examined influences on the growth of the subgingival bacteria and the pH value of their culture environment.