Locally delivered antimicrobials adjunctive to scaling and root planing provide additional PD reduction and CAL gain in the treatment of chronic periodontitis.
Explore the source record for details and available documents.
Comment↗
Biomedical subjects
Thomas F Flemmig
Publications and source records attributed to Thomas F Flemmig.
Local and systemic conditions potentially compromising osseointegration. Consensus report of Working Group 3.
Explore the source record for details and available documents.
Alveolar Ridge Augmentation↗
Molecular epidemiology of oral treponemes in patients with periodontitis and in periodontitis-resistant subjects.
The etiologic role of oral treponemes in human periodontitis is still under debate. Although seen by dark-field microscopy in large numbers, their possible role is still unclear since they comprise some 60 different phylotypes, most of which are still uncultured. To determine their status as mere commensals or opportunistic pathogens, molecular epidemiological studies are required that include both cultured and as-yet-uncultured organisms. Here we present such data, comparing treponemal populations from chronic periodontitis (CP) or generalized aggressive periodontitis (GAP) patients. As a periodontitis-resistant (PR) control group, we included elderly volunteers with more than 20 natural teeth and no history of periodontal treatment and no or minimal clinical signs of periodontitis. Almost every treponemal phylotype was present in all three groups. For most treponemes, the proportion of subjects positive for a certain species or phylotype was higher in both periodontitis groups than in the PR group. This difference was pronounced for treponemes of the phylogenetic groups II and IV and for Treponema socranskii and Treponema lecithinolyticum. Between the periodontitis groups the only significant differences were seen for T. socranskii and T. lecithinolyticum, which were found more often in periodontal pockets of GAP patients than of CP patients. In contrast, no difference was found for Treponema denticola. Our findings, however, strengthen the hypothesis of treponemes being opportunistic pathogens. It appears that T. socranskii, T. lecithinolyticum and group II and IV treponemes may represent good indicators for periodontitis and suggest the value of the respective probes for microbiological diagnosis in periodontitis subjects.
Adult↗
Sampling strategy for intraoral detection of periodontal pathogens before and following periodontal therapy.
BACKGROUND: The aim of this study was to identify a sampling strategy with high probability for detecting oral colonization by Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Eikenella corrodens, Tannerella forsythensis, Prevotella intermedia, Prevotella nigrescens, and Treponema denticola before and following mechanical periodontal therapy. METHODS: Samples were taken from the following intraoral sites in 35 patients with untreated chronic periodontitis before and 1.5, 3, and 6 months after non-surgical periodontal therapy: supra- and subgingival plaque from the deepest pockets in each sextant; pooled supra- and subgingival plaque from another six randomly selected, less affected teeth; mucosal swab samples from the tongue, tonsils, throat, and buccal mucosa; and stimulated and unstimulated saliva. Microbial species were identified by polymerase chain reaction (PCR). RESULTS: Of the sampling of all assessed sites, the highest probability for simultaneously detecting the tested pathogens was found in respect to the combination of supra- and subgingival plaque samples taken from the most affected tooth in each sextant in untreated patients (probability: 83% to 95% for the assessed bacteria). These results were consistently observed throughout the study period. CONCLUSIONS: For determining the intraoral carrier state of patients with periodontitis, a combined sample of supra- and subgingival plaque taken from the deepest periodontal pocket in each sextant may yield the most reliable result. This sampling strategy may be used in routine microbial testing and clinical research.
Bacteria, Anaerobic↗
Caspase activation is involved in chronic periodontitis.
Periodontitis, a common infectious disease, is initiated by various gram-negative bacteria and characterized by the destruction of the periodontal tissue. Here, we investigated the role of caspases, intracellular proteases that are the key mediators of apoptosis. We show that activation of caspase-3 and caspase-7 is considerably enhanced in gingival tissue from patients with periodontitis. We also demonstrate in in vitro experiments that various periodontopathic bacteria exert a direct growth-suppressing effect and, moreover, can trigger a host-mediated cytotoxic activity involving the CD95 death receptor. Our data suggest that caspase activation is a prominent feature in periodontitis-associated tissue injury.
Adult↗
Adjunctive antimicrobial therapy of periodontitis: long-term effects on disease progression and oral colonization.
BACKGROUND: This study assessed the long-term effects of adjunctive antimicrobial therapy on periodontal disease progression and oral colonization. METHODS: Patients with previously untreated chronic periodontitis and subgingival Actinobacillus actinomycetemcomitans and/or Porphyromonas gingivalis were randomly assigned to subgingival scaling without (control group) or with systemic amoxicillin plus metronidazole and CHX irrigation (test group). Relative attachment levels were determined and subgingival and mucosal plaque samples were taken at baseline, at 10 days (plaque only) and at 3, 6, 9, 12, 18, and 24 months following initial therapy. During maintenance therapy, patients received supragingival debridement only. RESULTS: After 24 months, the 18 test group patients showed at sites with initial probing depths (PD) > or =7 mm a significantly (P <0.05) higher frequency of 2 mm or more attachment gain (37.3% +/- 4.6%) and lower frequency of attachment loss (7.2% +/- 3.1%) compared to the 17 controls (8.2% +/- 3.9% and 19.1% +/- 13.1%, respectively). Compared to controls, the intraoral prevalence of A. actinomycetemcomitans (up to 18 months) and P. gingivalis (up to 3 months) decreased and that of Eikenella corrodens (at 10 days) increased in test patients (P <0.05). In both treatment groups, the detection frequency of Tannerella forsythensis decreased transiently, while an overall increase was recorded for Treponema ssp. CONCLUSIONS: Over the 24-month period, a single course of the administered adjunctive antimicrobial therapy led to a relative risk reduction of 62% for attachment loss at deep sites. However, with the exception of A. actinomycetemcomitans, it failed to induce long-term changes in the prevalence profiles of oral colonization.
Actinobacillus Infections↗
Microbiological shifts in intra- and extraoral habitats following mechanical periodontal therapy.
OBJECTIVES: The aim of the present study was to analyze the intra- and extraoral colonization dynamics of periodontal pathogens following supra- and subgingival debridement. MATERIAL AND METHODS: Thirty five patients with chronic periodontitis were enrolled in the study. Supra- and subgingival plaque samples, saliva, and swab samples from mucosa and extraoral sites were taken at baseline and 6 weeks, 3 months and 6 months after mechanical periodontal therapy. Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Eikenella corrodens (Ec), Tannerella forsythensis (Tf), Prevotella intermedia (Pi), Prevotella nigrescens (Pn), and Treponema denticola (Td) were identified by PCR. RESULTS: Supra- and subgingival debridement decreased the number of subgingival sites infected with the analyzed pathogens only transiently, if at all. However, the detection frequencies of Tf, Td, Ec, Pi, and Pn in the supragingival region, of Pg, Td, and Pn at the oral mucosa sites (mostly the tongue), and of all pathogens except Aa in saliva increased over the 6-month observation period. Td was the only pathogen recorded in notable quantities in the extraoral habitat (external ear canal). CONCLUSION: The results indicate that supra- and subgingival debridement results in a dissemination of periodontal pathogens within the oral cavity.
Bacteria, Anaerobic↗
Specific antibiotics in the treatment of periodontitis--a proposed strategy.
BACKGROUND: The purpose of the present study was to propose a strategy for the selection of antibiotics that specifically target complexes of periodontal pathogens present in patients with periodontitis. METHODS: Seven hundred seventy-four (774) patients with various forms of periodontitis were included in the study. Subgingival plaque samples were taken from the deepest periodontal pockets in each quadrant using a sterile curet, and pooled. Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Eikenella corrodens, Tannerella forsythensis, Prevotella intermedia, and Prevotella nigrescens were identified by polymerase chain reaction, and the prevalence of combinations of these pathogens was determined. To each pathogen complex (PC), i.e., combination of pathogens, those antibiotics were assigned that were most specific according to the published minimum inhibitory concentration (MIC90) values and the gingival crevicular fluid (GCF) concentrations achievable in vivo. Antibiotic GCF concentrations had to be at least 10 times the MIC90 values, and the narrowest spectrum was selected with respect to the assessed periodontal pathogens. RESULTS: Nine major PCs (each > or = 3% of all patients) were found in 73.4% of all patients, whereas 38 minor PCs (each < 3% of all patients) were distributed in 26.6% of all patients. Ten different antibiotic regimens were found to be specific for the total of 46 PCs; i.e., metronidazole and amoxicillin in 11 PCs (55.0% of all patients), metronidazole and amoxicillin/clavulanic acid or metronidazole and ciprofloxacin in 13 PCs (18.9%), amoxicillin in 4 PCs (8.3%), doxycycline in 2 PCs (6.1%), metronidazole in 8 PCs (4.1%), amoxicillin/clavulanic acid in 3 PCs (2.9%), clindamycin in 2 PCs (1.5%), ciprofloxacin in 2 PCs (0.4%), and tetracycline in 1 PC (0.3%). CONCLUSION: The results of the study indicate that there are at least 46 different combinations of the assessed periodontal pathogens in subjects with periodontitis, and at least 10 different antibiotic regimens might be required to specifically target the various pathogen complexes.
Anti-Bacterial Agents↗
Safety and efficiency of novel sonic scaler tips in vitro.
BACKGROUND: The aim of the study was to evaluate a novel sonic scaler tip for subgingival root surface instrumentation combining high efficiency in calculus removal with minimized risk of root damage through subgingival debridement. METHODS: A metal sonic scaler tip with a paddle-like working end covered with spheroid convexities of 0.8 mm diameter and 0.3 mm height was designed from the aspect of optimized adaptation to the root anatomy (tip-end dimension: 3.0 x 1.5 x 0.6 mm). Using a customary sonic scaler tip as control, instrument efficiency was quantified by measuring the time needed to completely remove calculus on extracted teeth (n=52) under standardized conditions. To quantify the amount of calculus removed, the mean calculus area per tooth was measured on photographs taken before instrumentation. The tips safety was evaluated instrumenting calculus-free root surfaces in vitro (n=18, lateral forces 0.5, 1, 2 N, 20 s instrumentation time, tip angulation 0 degrees ) with subsequent laser-optical determination of resulting root substance loss. RESULTS: Debridement efficiency was significantly higher for the novel tip (0.78+/-0.81 mm2/s completely debrided) than for the conventional tip (0.42+/-0.33 mm2) (Mann-Whitney test, p<0.05). Concerning instrument safety, the novel tip caused significantly less root substance loss than the conventional tip. CONCLUSION: The novel scaler tip appears to be significantly more efficient in calculus removal and less damaging to the root surface than the assessed conventional tip.
Dental Calculus↗
Multilocus sequence analysis of Porphyromonas gingivalis indicates frequent recombination.
In this study, the genetic relationship of 19 Porphyromonas gingivalis isolates from patients with periodontitis was investigated by multilocus sequence analysis. Internal 400-600 bp DNA fragments of the 10 chromosomal genes ef-tu, ftsQ, hagB, gpdxJ, pepO, mcmA, dnaK, recA, pga and nah were amplified by PCR and sequenced. No two isolates were identical at all 10 loci. Phylogenetic analyses indicated a panmictic population structure of P. gingivalis. Split decomposition analysis, calculation of homoplasy ratios and analyses of clustered polymorphisms all indicate that recombination plays a major role in creating the genetic heterogeneity of P. gingivalis. A standardized index of association of 0.0898 indicates that the P. gingivalis genes analysed are close to linkage equilibrium.
Chromosomes, Bacterial↗
Implants in the medically compromised patient.
Dental clinicians are confronted with an increasing number of medically compromised patients who require implant surgery for their oral rehabilitation. However, there are few guidelines on dental implant therapy in this patient category, so that numerous issues regarding pre- and post-operative management remain unclear to the dental clinician. Therefore, the aim of the present review is to offer a critical evaluation of the literature and to provide the clinician with scientifically based data for implant therapy in the medically compromised patient. This review presents the current knowledge regarding the influence of the most common systemic and local diseases on the outcome of dental implant therapy, e.g., abnormalities in bone metabolism, diabetes mellitus, xerostomia, and ectodermal dysplasias. Specific pathophysiologic aspects of the above-mentioned diseases as well as their potential implications for implant success are critically appraised. In line with these implications, guidelines for pre- and post-operative management that may assist in the successful implant-supported rehabilitation of this patient category are proposed.
Bone Diseases, Metabolic↗
Subgingival plaque removal at interdental sites using a low-abrasive air polishing powder.
BACKGROUND: The aim of the study was to test the efficacy of a novel low-abrasive air polishing powder in subgingival plaque removal at interdental sites during periodontal maintenance therapy (PMT). METHODS: Using a split mouth design, subgingival plaque was removed in 23 PMT patients using a low abrasive powder using a standard air polishing unit (test) or curets (positive control). Before and immediately after treatment, subgingival plaque samples were taken from interdental sites with 3 to 5 mm probing depth (PD) at 2 test teeth and 2 positive control teeth. To evaluate the influence of sampling on the microflora, plaque samples were also taken twice at 2 teeth without therapy with PD of 3 to 5 mm (negative control). PMT treatment and plaque sampling were repeated 3 times at quarterly intervals. Anaerobe cultivation was utilized to assess the mean reduction of total colony forming units (CFU) immediately after treatment. RESULTS: Test treatment resulted in a significantly greater reduction in subgingival bacterial counts (log 1.9 +/- 0.7) than positive control treatment (log 1.1 +/- 0.6) and subgingival plaque sampling alone (log 0.5 +/- 0.5; P < 0.05). Differences between positive and negative control were not significant (P < 0.05). CONCLUSION: The novel low-abrasive air polishing powder is superior to curets in removing subgingival plaque at interdental sites with up to 5 mm probing depth in PMT.
Adolescent↗
Powder emission rates of four air polishing devices.
OBJECTIVES: Although highly effective in plaque and stain removal, the use of air polishing devices (APDs) on denuded root surfaces may lead to clinically relevant loss of tooth substance. As the amount of powder emitted by an APD may have a significant impact on the safety and efficacy of the instruments, the purpose of the study was to quantify the amount of powder emitted by APDs depending on their powder filling status and powder setting. METHODS: Four different APDs were filled to maximum level and the cumulative amount of powder emitted, depending on instrument settings and filling status, was quantified during 15 subsequent 120-s periods of use. Differences in powder emission were analyzed using anova repeated measures. RESULTS: Exact powder dosage was possible in one APD only (Dentsply Prophyjet) where emission rates also remained constant over the first five periods assessed. In the three other APDs assessed (EMS Air-Flow, Satellec Air-Max, KaVo Prophyflex II powder emission depended on the amount of powder present in the powder chamber and declined with ongoing use. Changes in powder setting had a significant impact on powder emission in all APDs assessed, apart from the KaVo Prophyflex II unit. CONCLUSIONS: Powder emission of APDs may vary greatly depending on the amount of powder present in the powder bowl. Therefore, instrument powder setting may not be a reliable parameter for safety and efficacy adjustments. This should be considered in clinical applications as well as in future research.
Air Abrasion, Dental↗
Antimicrobial effects of mechanical debridement.
Self-performed plaque removal using manual or powered toothbrushes and interdental cleaning devices is improved in subjects that have received oral hygiene instructions. Personal oral hygiene coupled with regular professional supragingival debridement may further improve the level of plaque control but still fails to achieve a completely plaque-free dentition. Both patient-performed and professional supragingival plaque removal has an effect on subgingival microbiota that is limited to the marginal 3 mm of the periodontal pocket. At sites with 4 mm or more of probing depth, only subgingival scaling leads to a significant reduction of the bacterial load. The subgingival microflora can be further reduced by pocket elimination surgery. Due to the sequence of bacterial recolonization that occurs following mechanical debridement, the level of periodontal pathogens such as B. forsythus, P. gingivalis and T. denticola may be reduced for several months. Mechanical debridement also influences the patient's immune system response, resulting in antibody titers and avidity against periodontal pathogens. As a basis for the restoration and maintenance of periodontal health, repeated subgingival debridement, as performed in supportive periodontal therapy, can reduce the number and proportions of periodontopathogenic bacteria in subgingival plaque. However, intensive subgingival scaling and root planing should be avoided in sites that probe less than 3 mm, as this is likely to traumatize the periodontium and cause attachment loss.
Antibody Formation↗