Clinical and microbiological features of refractory periodontitis subjects

Abstract

The purpose of this investigation was to compare the clinical parameters and the site prevalence and levels of 40 subgingival species in successfully treated and refractory periodontitis subjects. 94 subjects received scaling and root planing and if needed, periodontal surgery and systemically administered tetracycline. 28 refractory subjects showed mean full mouth attachment loss and/or > 3 sites showing attachment loss > 2.5 mm within 1 year post-therapy. 66 successfully treated subjects showed mean attachment level gain and no sites with attachment loss > 2.5 mm. Baseline subgingival plaque samples were taken from the mesial aspect of each tooth and the presence and levels of 40 subgingival taxa were determined using whole genomic DNA probes and checkerboard DNA-DNA hybridization. The mean levels and % of sites colonized by each species (prevalence) was computed for each subject and differences between groups sought using the Mann-Whitney test. Most of the 40 species tested, including Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola and Bacteroides forsythus, were equally or less prevalent in the refractory group. Prevotella nigrescens was significantly more prevalent in successfully treated subjects, while refractory subjects harbored a larger proportion of Streptococcus species, particularly Streptococcus constellatus. The odds of a subject being refractory was 8.6 (p < 0.001) if S. constellatus constituted > or = 3.5% of the total DNA probe count. Since few microbiological differences existed between treatment outcome groups using DNA probes to known species, the predominant cultivable microbiota of 33 subgingival samples from 14 refractory subjects was examined. 85% of the 1649 isolates were identified using probes to 69 recognized subgingival species. The remaining unidentified strains were classified by analyzing 16S rRNA gene sequences. Many sequenced isolates were of taxa not considered a common part of the oral microbiota such as Acinetobacter baumanni, Gemella haemolysans, Enterococcus faecalis, Staphylococcus warneri, Pseudomonas aeruginosa and novel species in the genera Bartonella, Ralstonia, Neisseria, Eubacterium, Rothia, Gordona, Gemella, Corynebacterium, Leptotrichia, and Actinomyces. Refractory subjects constituted a heterogeneous group based on their subgingival microbiota. As a group, they did not harbor more of the "classic" periodontopathogens, although elevated proportions of S. constellatus were found.

Prevalence of "non-oral" pathogenic bacteria in subgingival biofilm of subjects with chronic periodontitis

“…in the subgingival microbiota of periodontitis patients in the Dominican Republic, whereas Ali and co-workers (2) observed a frequency of 61.1% of enterics in the subgingival microbiota of periodontitis subjects from Romania. The species P. aeruginosa and A. baumannii, important etiologic agents of nosocomial infections, have been associated with refractory periodontitis, probably due to their elevated resistance to mechanical and antimicrobial therapies (4,29,34). Another pathogen related to antimicrobial resistance is E. faecalis.…”

Evaluation of Enterococcus faecalis, Staphylococcus warneri and Staphylococcus aureus species in adults with generalized chronic periodontitis

“…Previous studies have also observed some association of the bacterial species E. faecalis 19 , S. warneri 14,[19][20][21][22] , and S. aureus [23][24] with periodontal diseases. Furthermore, a recent systematic review by our research group 10 that evaluated the weight of evidence of the existence of new periodontal pathogens suggested that 32 new strains might be associated with the etiology of periodontal diseases.…”

“…Whereas, S. warneri was identified by means of genetic sequencing in individuals who did not respond well to periodontal therapy (previously called "refractory periodontitis") 21 . Contrary to other types of staphylococcus, S. warneri has been found in elevated quantities in implants in function for 10 years and showed positive correlation with peri-implant inflammation 14 .…”

Effects Of Scaling And Root Planing And 0.2 % Chlorhexidine Rinse On Clinical And Microbiological Parameters In Generalised Chronic Periodontitis– A Clinico - Microbiological Study

“…The better clinical and microbiological effects observed with the combination of SRP and CHX in this study might be attributed to a beneficial effect of CHX rinsing on subgingival microbial recolonization. Maintaining low levels of supragingival plaque and disturbing periodontal pathogen reservoirs that are not reached by SRP, such as tonsils, tongue, saliva and oral mucous membranes, [29,30] could have a positive influence on recolonization of the recently scaled pockets. It can be concluded from the results of the present study that the treatment with SRP and CHX improved clinical and microbiological parameters compared to the SRP alone as a monotherapy.…”