Periodontal pathogens and associated factors in aggressive periodontitis: results 5-17 years after active periodontal therapy

OBJECTIVES To assess the association between presence of periodontal pathogens and recurrence of disease in patients with aggressive periodontitis (AgP) after active periodontal therapy (APT) and further influencing factors. MATERIAL & METHODS Microbiological samples were taken from 73 patients with AgP 5-17 years after APT at 292 sites (deepest site per quadrant). Real-time polymerase chain reactions were used to detect the periodontal pathogens Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola. Uni- and multivariate analyses evaluated the associations between pathogens and recurrence of disease, smoking and adjunctive antibiotic therapy. RESULTS At re-examination A. actinomycetemcomitans could be detected in six patients (8.2%), P. gingivalis in 24 (32.9%), T. forsythia in 31 (42.5%) and T. denticola in 35 (48.0%). Increased levels of T. forsythia and T. denticola at re-examination were significantly associated with recurrence of disease in multivariate analyses (OR: 12.72, p < 0.001; OR 5.55, p = 0.002 respectively). Furthermore, high counts of T. denticola were found in patients with increased percentage of sites with clinical attachment levels (CAL) ≥ 6 mm compared to those with low counts (13.8% versus 3.2%, p = 0.005). CONCLUSION In patients with recurrence of disease T. forsythia and T. denticola were detected more frequently and in higher counts. Furthermore, T. denticola was found more frequently in patients with increased CAL.

Microbiota at teeth and implants in partially edentulous patients. A 10-year retrospective study.

OBJECTIVE To determine the microbiota at implants and adjacent teeth 10 years after placement of implants with a sandblasted and acid-etched surface. MATERIAL AND METHODS Plaque samples obtained from the deepest sites of 504 implants and of 493 adjacent teeth were analyzed for certain bacterial species associated with periodontitis, for staphylococci, for aerobic gram-negative rods, and for yeasts using nucleic acid-based methods. RESULTS Species known to be associated with periodontitis were detectable at 6.2-78.4% of the implants. Significantly higher counts at implants in comparison with teeth were assessed for Tannerella forsythia, Parvimonas micra, Fusobacterium nucleatum/necrophorum, and Campylobacter rectus. Higher counts of periodontopathogenic species were detectable at implants of current smokers than at those of non-smokers. In addition, those species were found in higher quantities at implants of subjects with periodontitis. The prevalence of Prevotella intermedia, Treponema denticola, C. rectus, and moreover of Staphylococcus warneri might be associated with peri-implant inflammation. Selected staphylococcal species (not Staphylococcus aureus), aerobic gram-negative rods, and yeasts were frequently detected, but with the exception of S. warneri, they did not show any association with periodontal or peri-implant diseases. CONCLUSIONS Smoking and periodontal disease are risk factors for colonization of periodontopathic bacteria at implants. Those bacterial species may play a potential role in peri-implant inflammation. The role of S. warneri needs further validation.

Host-derived biomarkers at teeth and implants in partially edentulous patients. A 10-year retrospective study.

OBJECTIVES To assess a selection of host-derived biomarkers in peri-implant sulcus fluid (PISF) and gingival crevicular fluid (GCF) from adjacent teeth 10 years following implant placement. MATERIAL AND METHODS Peri-implant sulcus fluid and GCF samples obtained from the deepest sites of 504 implants and 493 adjacent teeth were analysed for levels of interleukin (IL)-1β, matrix metalloproteinase (MMP)-3, MMP-8, MMP-1, and MMP-1 bound to tissue inhibitor of MMP (TIMP)-1 (MMP-1/TIMP-1) by enzyme-linked immunosorbent assay (ELISA) technique. RESULTS Overall, MMP-8 was detected in 90% of the sites. In more than 50% of the sites, IL-1β was identified while in 30% of the sites MMP-1, MMP-1/TIMP-1 and MMP-3 were found over the detection level. Increased biomarkers levels from PISF and GCF were positively correlated (r = 0.375-0.702; P < 0.001). However, no qualitative and quantitative differences were found between PISF and GCF. The levels of MMP-1 were negatively correlated with those of MMP-1/TIMP-1 at implants (r = -0.644; P < 0.001). Median MMP-1 levels at implants were high (5.17 pg/site) in subjects with severe chronic periodontitis and low in patients with mild-to-moderate chronic periodontitis (0 pg/site; P = 0.026) or gingivitis (0 pg/site; P = 0.034). Levels of IL-1β were found to be different in GCF according to the periodontal conditions (P = 0.001) with the highest level found in mild-to-moderate periodontitis (6.2 pg/site). Clinical attachment levels at implants demonstrated an inverse correlation with MMP-1/TIMP-1 (r = -0.147; P = 0.001). CONCLUSIONS Increased levels of MMP-8 and IL-1β in PISF or GCF may be associated with inflammation around teeth and implants while lower levels of MMP-1/TIMP-1 may be an indicator of disease progression around implants.