Bacterial markers vs. clinical markers to predict progression of chronic periodontitis: a 2-yr prospective observational study.

The aim of this study was to identify sites at risk for future progression, during 2 yr of maintenance, in patients with chronic periodontitis (CP), based on longitudinal clinical and microbiological monitoring. At baseline (2003), clinical and microbiological features were recorded in 50 patients with CP. Two microbial samples were obtained from each patient (one from a clinically healthy site and one from a periodontitis site) and these were analyzed using DNA-DNA hybridization involving 25 bacterial species. After non-surgical periodontal therapy, clinical and microbiological re-examinations were performed at the same or similar sites at 2 yr (2006) and 4 yr (2008) of maintenance. Plaque, bleeding on probing (BoP), and the number of sites with periodontitis (≥4 mm) and severe periodontitis (≥6 mm) all showed a significant decrease at 2 and 4 yr of maintenance after non-surgical intervention. Checkerboard analysis revealed that various bacteria with a high colonization score (≥3) corroborated the clinical findings of pathology at 2003, 2006, and 2008. Different clusters of bacteria, not just the 'red complex', were able to predict progression of chronic periodontitis during 2 yr of maintenance (2006-2008). Therefore, quantified bacterial markers (reflecting bacterial load) and the clinical markers BoP and periodontal probing depth show comparable prediction of future disease condition.

A follow-up study of peri-implantitis cases after treatment.

AIM: The aim of this retrospective study was to follow patient cases in a longitudinal manner after peri-implantitis treatment. MATERIALS AND METHODS: Two hundred and eighty-one patient cases were selected consecutively from the archives of the Oral Microbiological Diagnostic Laboratory, Gothenburg, Sweden based on microbial analysis of bacterial samples taken from diseased implants. It was feasible to follow-up 245 patients after treatment for a period ranging from 9 months to 13 years. RESULTS: In 54.7% of the patients it was not feasible to arrest progression of peri-implantitis. Smoking and smoking dose were found to be significantly correlated to failure of peri-implantitis treatment (p<0.05). Early disease development was also significantly associated with failure (p<0.05). Bone plasty in conjunction to antibiotics during surgery was significantly associated with arrested lesions (p<0.05). In a multiple regression model disease development was the only independent variable to significantly predict the likelihood of treatment success. CONCLUSIONS: Peri-implant health may not be easy to establish, especially in cases that develop disease early. Homogenous treatment protocols rather than empirical treatment attempts should be adopted.

The secretion of cytokines by peripheral blood mononuclear cells of patients with periodontitis and healthy controls when exposed to H2S.

Background: Hydrogen sulfide(H2S) is a bacterial metabolite produced as a result of bacterial growth in subgingival pockets, suggested to partake in the pathogenesis of periodontitis. H2S has previously been shown to induce the secretion of the pro-inflammatory cytokines IL-1ß and IL-18 via the NLRP3 inflammasome in monocytes. Objective: To investigate the non-NLRP3 inflammasome-dependent immunological response of human peripheral blood mononuclear cells (PBMCs) of periodontitis patients and healthy controls exposed to H2S in vitro. Methods: PBMCs of periodontitis patients(N = 31) and healthy controls(N = 32) were exposed to 1 mM sodium hydrosulfide (NaHS) at 37°C for 24 h and the secretion of cytokines was compared to resting cells. TNF-α, IFN-γ, IL-6, IL-8, IL-12p40, IL-12p70, IL-17, MCP-1, and IL-1Ra secretions were measured with Bio-Plex Pro™ Human Cytokine Assay. Results: H2S triggered the secretion of the pro-inflammatory IFN-γ, IL-6, IL-17, TNF-α, IL-12p40, and IL-12p70, while the reverse was seen for IL-1Ra. In addition, a higher basal secretion of IFN-γ, IL-6, IL-12p70, IL-17 and MCP-1 was seen from PBMCs of periodontitis patients compared to healthy controls. Conclusion: The bacterial metabolite H2S triggers the secretion of pro-inflammatory cytokines from PBMCs and may thus have a prominent role in the host-bacteria interplay in periodontitis.

H2S mediates increased interleukin (IL)-1ß and IL-18 production in leukocytes from patients with periodontitis.

Background: The mechanisms involved in the interplay between the bacteria and the host cells in periodontitis are not fully understood. Aim: To investigate the effect of the bacterial metabolite H2S on the pro-inflammatory cytokines interleukin (IL)-1ß and IL-18 from periodontitis patients and healthy controls, and to evaluate the composition of the subgingival microbiota with its capacity to produce H2S. Methods: Subgingival bacterial samples from patients with periodontitis (N=32) and healthy controls (N=32) were investigated for H2S production and bacterial composition. Peripheral blood mononuclear cells (PBMCs) were cultured in the presence/absence of 1mM H2S for 24h and cytokine concentrations were measured. Results: Subgingival plaque from periodontitis patients had more H2S producing bacteria and produced more H2S, than healthy controls. PBMCs exposed to H2S secreted significantly more IL-1ß and IL-18 (p<0.0001) than untreated control PBMCs from both groups. PBMCs from the periodontitis patients secreted higher levels of the cytokines, both spontaneously (IL-1ß p=0.0001; IL-18 p=0.09) and after exposure to H2S (IL-1ß p=0.03; IL-18 p=0.04), which is a new finding not previously reported. Conclusions: H2S, from the subgingival microbiota, can contribute to a host inflammatory response through secretion of the pro-inflammatory cytokines IL-1ß and IL-18. Since this response differs between individuals, it may also reflect the susceptibility of the host to develop periodontitis.

Phenotype, genotype, and antibiotic susceptibility of Swedish and Thai oral isolates of Staphylococcus aureus.

OBJECTIVE: The present study investigated phenotypes, virulence genotypes, and antibiotic susceptibility of oral Staphylococcus aureus strains in order to get more information on whether oral infections with this bacterium are associated with certain subtypes or related to an over-growth of the S. aureus variants normally found in the oral cavity of healthy carriers. MATERIALS AND METHODS: A total number of 157 S. aureus strains were investigated. Sixty-two strains were isolated from Swedish adults with oral infections, 25 strains were from saliva of healthy Swedish dental students, and 45 strains were from tongue scrapings of HIV-positive subjects in Thailand, and 25 Thai strains from non-HIV controls. The isolates were tested for coagulase, nitrate, arginine, and hemolysin, and for the presence of the virulence genes: hlg, clfA, can, sdrC, sdrD, sdrE, map/eap (adhesins) and sea, seb, sec, tst, eta, etb, pvl (toxins). MIC90 and MIC50 were determined by E-test against penicillin V, oxacillin, amoxicillin, clindamycin, vancomycin, fusidic acid, and cefoxitin. RESULTS: While the hemolytic phenotype was significantly (p<0.001) more common among the Thai strains compared to Swedish strains, the virulence genes were found in a similar frequency in the S. aureus strains isolated from all four subject groups. The Panton-Valentine leukocidin (PVL) genotype was found in 73-100% of the strains. More than 10% of the strains from Swedish oral infections and from Thai HIV-positives showed low antibiotic susceptibility, most commonly for clindamycin. Only three methicillin-resistant S. aureus (MRSA) strains were identified, two from oral infections and one from a Thai HIV patient. CONCLUSIONS: S. aureus is occasionally occurring in the oral cavity in both health and disease in Sweden and Thailand. It is therefore most likely that S. aureus in opportunistic oral infections originate from the oral microbiota. S. aureus should be considered in case of oral infections and complaints and the antibiotic susceptibility (including MRSA) should regularly be checked. The frequent presence of S. aureus, although in low numbers among students and staff, emphasizes the importance of standard infection control precautions and of using diagnostic test in the dental clinic.

Five-year clinical, microbiological, and radiological outcome following treatment of peri-implantitis in man.

BACKGROUND: The aim of this study was to evaluate the long-term outcome of a combined surgical and antimicrobial treatment of peri-implantitis lesions in humans. METHODS: Nine partially dentate individuals with titanium implants demonstrating a marginal bone loss of > or = three threads as compared to baseline measurements made from 1-year intra-oral radiographs, bleeding on probing, and/or suppuration from the peri-implant sulci were included in the study. In each individual, subgingival bacterial samples were obtained and subjected to microbiological analysis by culture. Surgical exposure of the lesions and cleaning of the implants using hydrogen peroxide were performed. The patients were given systemic antibiotics according to a susceptibility test of target bacteria. The treatment was evaluated clinically, microbiologically, and radiograpically at 6 months, 1 year, and 5 years. RESULTS: Seven out of 26 implants with peri-implantitis at baseline were lost during the 5-year follow-up period despite a significant reduction in the presence of plaque and gingival bleeding. Four implants continued to lose bone, 9 had an unchanged bone level, and 6 gained bone. Five of the patients were treated with antibiotics directed against putative periodontopathogens, i.e., A. actinomycetemcomitans, P. intermedia, or P. gingivalis; three patients were treated for presence of enterics (E. coli and E. cloace); and, in one patient, treatment was directed against S. aureus. CONCLUSIONS: Despite treatment and retreatment, seven implants were lost. However, the applied surgical and antimicrobial treatment strategy for advanced peri-implantitis lesions was successful in 58% of the implants treated during the 5-year follow-up period. Smoking seemed to be a negative risk factor for treatment success.

Enamel matrix proteins in the treatment of deep intrabony defects.

BACKGROUND: The present study evaluated the healing of enamel matrix derivative (EMD) proteins in the treatment of periodontal lesions with deep intrabony defects. METHODS: Ten deep intrabony defects in 7 periodontal patients were treated and followed for 1 year. The sites had a probing depth (PD) > or = 8 mm; clinical attachment level (CAL) > or = 9 mm, and intrabony component depth > or = 5 mm. All subjects received therapy prior to surgery and had a plaque score (PI) < or = 10%. Full thickness flaps were elevated buccally and lingually, granulation tissue was removed from the defects, and the root surfaces were planed. A 24% EDTA gel was applied followed by the enamel matrix protein preparation. The flaps were closed with interrupted sutures. The patients rinsed with a chlorhexidine solution twice a day for 6 weeks. They were recalled every 2 weeks for 6 months for professional tooth cleaning and then every 4 weeks for an additional 6 months. The experimental sites were re-examined 6 and 12 months after regenerative surgery. RESULTS: At the 1-year examination, the mean CAL gain was 6.5 mm, the mean PD was 3.2 mm, and mean radiographic bone fill was 4.7 mm. CONCLUSIONS: The application of enamel matrix proteins in combination with open flap curettage and root planing resulted in a gain of CAL and bone fill in deep intrabony defects.

Microbiologic diagnostics at titanium implants.

BACKGROUND: The microbiota found at periimplant lesions have been shown to contain putative periodontal pathogens as well as opportunistic species such as Staphylococcus spp, enterics, and Candida spp. Therefore, a microbiologic diagnosis may be of value as guidance before treatment of such lesions. PURPOSE: The aim of this study was to evaluate the prevalence of some putative pathogens associated with long-term followed-up cases using two different microbiologic procedures. MATERIALS AND METHODS: Fifteen subjects contributed with plaque samples from teeth and implants; these were analyzed with respect to 18 putative periimplant pathogens using cultural methods and a deoxyribonucleic acid DNA-DNA hybridization technique. RESULTS: The number of individuals positive for the analyzed pathogens was similar in samples taken from teeth and implants when analyzed with the DNA-DNA hybridization technique. When comparing detection frequency by culture procedure and by "checkerboard" technique at implants, the number of individuals positive for these species was lower with the traditional culture technique than with the checkerboard analyses. Using a higher cutoff point (> or = 4) with the checkerboard technique, the number of positive individuals was generally lower than that found with the culture technique. When comparing the techniques on an implant site level, the prevalence obtained by culture was lower for all analyzed species. If the specific species were present in the samples analyzed by the checkerboard technique, they were present only in every second sample analyzed with the culture technique. The high specificity values showed that if the checkerboard technique did not detect any Porphyromonas gingivalis, Prevotella intermedia, Actinobacillus actinomycetemcomitans, or Fusobacterium nucleatum, the bacteria were also undetectable by the culture technique. The two methods therefore did not overlap but did supplement each other. CONCLUSIONS: Based on the current results it is recommended that the technique used when analyzing microbiota around titanium implants should be a combination of the two protocols mentioned as they seem to give the most comprehensive outcome when used together.

Detection of periodontal markers in chronic periodontitis.

The aim was to compare the detection frequency of periodontopathogens by using the Pado Test 4.5 and checkerboard DNA-DNA hybridization technique in chronic periodontitis patients.Thirty patients with chronic periodontitis were tested cross-sectionally with DNA/RNA oligogenomic probe method (IAI Pado Test 4.5) and DNA/DNA whole genomic probe (checkerboard) method. Samples were taken by two paper points at the deepest site in each of the four quadrants and pooled into one sample for each of the two methods. The samples were sent to the two laboratories (IAI, Zuchwil, Switzerland, and Oral Microbiology Laboratory, University of Gothenburg, Sweden) and were analyzed in a routine setting for the presence and amount of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola.While Pado Test 4.5 detected the four periodontal pathogens in 11 (36.7%) of the patients, the checkerboard method showed presence in all patients (100%) using the lower score (Score 1 corresponding to 10(4) bacterial cells) and 16 (53.3%) using a higher treshold (score 3 corresponding to between >10(5) and 10(6) cells).The results of the present study showed low agreement for a positive microbiological outcome using the two diagnostic methods. It was also concluded that microbiological analysis in practice should include a larger number of bacterial species to better serve as markers for a diseased associated flora in chronic periodontitis cases.

Microbiological effect of the use of an ultrasonic device and iodine irrigation in patients with severe chronic periodontal disease: a randomized controlled clinical study.

OBJECTIVE: Instrumentation of the subgingival area is aimed at removing as much as possible of the bacterial biofilm and subgingival calculus. Since mechanical root debridement is a technically demanding procedure, antiseptics and antibiotics delivered either locally or systemically have been used as adjunct to scaling and root-planning procedures in order to control the subgingival biofilm and thereby enhance the treatment outcome. Our aim was to study the microbiological effect of ultrasonic debridement with or without povidone-iodine (PVP-iodine) in the treatment of severe chronic periodontitis. MATERIAL AND METHODS: Twenty patients were recruited to the study. Each test site and the related quadrant were randomly assigned to one of four different treatment modalities: ultrasonic scaling+subgingival irrigation with 0.5% PVP-iodine for 5 min/tooth, ultrasonic scaling+subgingival irrigation with sterile saline solution for 5 min/tooth, subgingival irrigation with sterile saline solution for 5 min/tooth and subgingival irrigation with 0.5% PVP-iodine for 5 min/tooth. The individuals were followed longitudinally for 6 months. RESULTS: The present study showed that non-surgical periodontal therapy with the use of an ultrasonic device was effective in reducing the analyzed putative periodontal bacteria. No statistically significant difference between ultrasonic+saline and ultrasonic+PVP-iodine was found. CONCLUSIONS: Ultrasonic debridement reduced the periodontal markers in patients with severe chronic periodontitis. The reduction was selective. A concentration of 0.5% PVP-iodine did not add any anti-microbiological effect compared to ultrasonic debridement alone.

Healing following ultrasonic debridement and PVP-iodine in individuals with severe chronic periodontal disease: a randomized, controlled clinical study.

OBJECTIVE: Antiseptics and antibiotics delivered either locally or systemically have been used as an adjunct to scaling and root planing procedures in order to control the subgingival biofilm and thereby enhancing the treatment outcome. The results presented in the literature are, however, inconclusive. Povidone-iodine (PVP-iodine) has a bactericidal effect and is effective against most bacteria, including putative periodontal pathogens. The aim of the present study was to evaluate the clinical effect of PVP-iodine as an adjunct to ultrasonic scaling in the treatment of severe chronic periodontitis. MATERIAL AND METHODS: Twenty patients were recruited to the study. Each test site and the related quadrant were randomly assigned to one of four different treatment modalities: ultrasonic scaling + subgingival irrigation with 0.5% PVP-iodine for 5 min/tooth, ultrasonic scaling + subgingival irrigation with sterile saline solution for 5 min/tooth, subgingival irrigation with sterile saline solution for 5 min/tooth, and subgingival irrigation with 0.5% PVP-iodine for 5 min/tooth. The individuals were followed longitudinally for 6 months. RESULTS: The present study showed that non-surgical periodontal therapy by means of an ultrasonic device was effective in attaining a healthy periodontal status in patients with severe periodontal lesions. No additive effect was found when PVP-iodine was included. CONCLUSIONS: Ultrasonic debridement using Odontogain is effective in controlling infection in patients with severe chronic periodontitis. PVP-iodine does not add any clinical benefit to the ultrasonic debridement alone under these circumstances.

IL-1RN gene polymorphism is associated with peri-implantitis.

OBJECTIVES: Interleukin (IL)-1alpha, IL-1beta and their natural specific inhibitor IL-1 receptor antagonist (IL-1ra) play a key role in the regulation of the inflammatory response in periodontal tissues. Polymorphisms in the IL-1 gene cluster have been associated with severe adult periodontitis. We aimed to investigate the IL-1 gene cluster polymorphisms in patients with peri-implantitis. MATERIAL AND METHODS: The study included 120 North Caucasian individuals. A total of 71 patients (mean age 68 years, 76% smokers) demonstrating peri-implantitis at one or more implants as evidenced by bleeding and/or pus on probing and bone loss amounting to >3 threads on Brånemark implants and 49 controls (mean age 66 years, 45% smokers) with clinical healthy mucosa and no bone loss around the implants were recruited for the study. The titanium implants, ad modum Brånemark, had been in function for at least 2 years. Mouthwash samples were collected and used for genotyping of the bi-allelic polymorphisms IL-1A(-889), IL-1B(+3953), IL-1B(-511) and a variable number of tandem repeat IL-1RN gene polymorphisms using PCR technique. RESULTS: Significant differences were found in the carriage rate of allele 2 in the IL-1RN gene between peri-implantitis patients and controls (56.5% vs. 33.3%, respectively; odds ratios (OR) 2.6; 95% confidence interval (CI) 1.2-5.6; P=0.015). Logistic regression analysis taking smoking, gender and age into account confirmed the association between the IL-1RN allele 2 carriers and peri-implantitis (OR 3; 95% CI 1.2-7.6; P=0.02). CONCLUSIONS: Our results provide evidence that IL-1RN gene polymorphism is associated with peri-implantitis and may represent a risk factor for this disease.

Long-term follow-up of osseointegrated titanium implants using clinical, radiographic and microbiological parameters.

The aim of this study was to longitudinally follow up osseointegrated titanium implants in partially dentate patients by clinical, radiographic and microbiological parameters in order to evaluate possible changes in the peri-implant health over time. Fifteen individuals treated with titanium implants, ad modum Brånemark, and followed for ten years were included in the study. Before implant placement ten years previously, the individuals had been treated for advanced periodontal disease and thereafter been included in a maintenance care program. The survival rate of the implants after ten years was 94.7%. The bone loss was 1.7 mm when using the abutment-fixture junction as a reference point. Of the individuals, 50% were positive for plaque at the implants. Bleeding on sulcus probing was present at 61% of the implant surfaces. Ten years previously, the individuals had been carriers of putative periodontal pathogens, such as Porphyromonas gingivalis, Prevotella intermedia, Actinobacillus actinomycetemcomitans, Capnocytophaga spp. and Campylobacter rectus, and were also carriers of these species at the current examination. The results of the present study suggest that the presence of these putative periodontal pathogens at implants may not be associated with an impaired implant treatment. These species are most likely part of the normal resident microbiota of most individuals and may therefore be found at random at both stable and progressing peri-implant sites.