No abstract

Abstract. This study was carried out to monitor the composition of the subgingival microflora in a group of chronic periodontitis‐susceptible subjects to determine whether microbial changes precede or follow detectable deterioration of their clinical status, and to determine if certain clinical or microbiological measurements can predict susceptibility to future periodontal breakdown. Twenty subjects previously treated for moderate to advanced chronic periodontitis were recruited from clinic patients receiving regular maintenance care. After obtaining their informed consent, a baseline examination was carried out of all vestibular, oral and mesial dental surfaces to record gingival index (GI), plaque index (PJI), probing depth (PD) and recession (RD). A pooled subgingival microbial sample was obtained with a curette from the surface with the greatest PD in each jaw sextant. After dispersion, the proportion of coccoid cells, motile rods and spirochetes was determined by dark field microscopy. All subjects then received a prophylaxis. All professional tooth cleaning was suspended for 1 year, but Che subjects returned to the clinic every 2 months for an examination, as described above‐Whenever the PD value of any surface exceeded by 3 mm or more the value recorded at baseline, the tooth was “exited” from the study for treatment by scaling and root planing. The results indicated that mean values for clinical and microbiological parameters changed little, if at all, between examinations for the 19 subjects who completed the study. However, significant differences were noted for clinical as well as microbiological measurements between individual subjects in the study. Positive correlations were established between % motile rods and GI and PII, between % spirochetes and PII and PD, and a negative correlation between % coccoid ceils and PII, when sampled surfaces only were considered. Significant positive correlations were shown between GI, PII and PD values, but not between RD values and GI, PII or PD. Six subjects without exited teeth exhibited no significant differences with respect to mean PII, GI, PD or RD values for seven examinations from subjects which had had two or more teeth exited from the study. However, subjects without exited teeth had significantly elevated proportions of coccoid cells and decreased proportions of motile rods and spirochetes as compared to subjects with two or more exited teeth. The proportions of spirochetes with or without motile rods in samples obtained at baseline were shown to be good predictors of periodontal deterioration as determined by the number of teeth which were exited for each subject during the course of this study. None of the clinical measurements could be used in this predictive capacity. Zusammenfassung Positive Korrelation zwischen dem Anteil subgingivaler Spirochaeten, motiler Bakterien und der Krankheitsbereitschaft für Parodontolysen Diese Studie wurde durchgeführt um die Zusammensetzung der subgingivaien Mikroflora in einer Gruppe Parodontitis‐anfaliiger Proban...