Comparison Of Periodontal Status And Subgingival Specific Plaque Composition In Experimental Peri-implant Mucositis And Experimental Gingivitis

Objective To monitor the dynamic changes of the clinical and subgingival specific plaque composition alterations occurring around the nature teeth and the titanium implants during the development of experimental gingivitis/peri-implant mucositis.This study is to explore the alterations and changes of subgingival specific plaque composition occurring around teeth and titanium implants during the development of experimental gingivitis/mucositis.And compare the differences between them.Material and methods A total of sixteen subjects with stable periodontal conditions(healthy or treated)and restored with dental implants were chosen.Implant and adjacent tooth form a experimental unit.All the subjects underwent a 3-week period of undisturbed plaque accumulation.Subsequently,a 3-week period with optimal plaque control was required.At days 0,7,14,21,28,35 and 42,clinical indexes including plaque index(PLI),gingival index(GI),modified bleeding index(m BI),and probing pocket depth(PPD)were evaluated.Meanwhile,subgingival/submucosal plaque samples were collected from each experimental unit.Several putative periodontal pathogens(Tannerella forsythia,Porphyromonas gingivalis,Fusobacterium nucleatum,Treponema denticola)in plaque samples were detected and analyzed using polymerase chain reaction(PCR).Results 1.Clinical indexesDuring 3 weeks of plaque accumulation,the median PLI,GI,m BI and PPD increased significantly at implants and teeth.Later the median PLI,GI,m BI and PPD decreasing gradually during 3 weeks of plaque control,which differed significantly compared with the level before plaque control(P<0.05).Over the 6-week experimental period,the median PLI were shown no statistically significant differences between teeth and implants(P>0.05).And the median PPD were statistically significantly higher at implants compared with teeth at any time points(P<0.05).Implant sites yielded a greater increase in the median GI and m BI compared with tooth sites during 3 weeks of plaque accumulation(P<0.05).Following reinstitution of oral hygiene practices,the median GI and m BI decreased at implants less than teeth(P<0.05).2.Content differences of subgingival specific plaqueNo differences in the 16 Sr DNA levels of T.f,P.g,F.n,T.d were found in both implant and tooth sites(P>0.05).No differences in the 16 Sr DNA levels of T.f,P.g,F.n,T.d between implant and tooth sites were found at any time points(P>0.05).Conclusion 1.In a short time,poor oral hygiene can lead to increasing plaque accumulation around implants.Peri-implant condition deteriorates,presented as aggravating gingival inflammation and increasing pocket depth.2.Under the conditions of experimental peri-implant mucositis and experimental gingivitis,there's no significant difference in plaque accumulation and subgingival specific plaque composition between implant and tooth sites,but peri-implant soft tissues developed a stronger inflammatory response compared with gingival counterparts.3.Traditionally mechanical self-plaque control can effectively improve the early stage inflammation around peri-implant,but the speed of improvement would be relatively slow compared with periodontitis.