Comparison of two full-mouth approaches in the treatment of peri-implant mucositis: a pilot study.

OBJECTIVES: The aim of the present study was to test the hypothesis that an additional full-mouth disinfection results in a greater clinical and microbiological improvement compared with sole mechanical debridement within one session in patients with peri-implant mucositis and treated chronic periodontitis. MATERIAL AND METHODS: The study included 13 partially edentulous patients (mean age 51.5 years) with treated chronic periodontitis and 36 dental implants with mucositis (bleeding on probing and/or a gingival index > or =1 at least at one site at baseline, absence of peri-implant bone loss during the last 2 years before baseline). After randomized assignment to a test and a control group, patients received a one-stage full-mouth scaling with or without chlorhexidine. Clinical and microbiological examination was performed at baseline, after 1, 2, 4 and 8 months. Additional microbial samples were taken 24 h after treatment. Microbiological analysis was performed by real-time polymerase chain reaction. RESULTS: Both treatment modalities resulted in significant reductions of probing depth at implant sites after 8 months, with no significant group differences. The bacteria at implants and teeth could be reduced in every group 24 h after treatment; however, this reduction was not significant after 8 months. CONCLUSIONS: Both treatment modalities led to an improvement of the clinical parameters and a temporary reduction of the microflora at implants with mucositis, but without significant inter-group differences after 8 months.

One-stage full-mouth disinfection versus quadrant and full-mouth root planing.

OBJECTIVE: The aim of this study was to test the hypothesis that the one-stage full-mouth disinfection (FMD) provides greater clinical and microbiological improvement compared with full-mouth scaling and root planing (FM-SRP) within 24 h and quadrant scaling and root planing (Q-SRP) in patients with generalized chronic periodontitis. MATERIAL & METHODS: Twenty-eight patients were randomized into three groups. 25 patients completed the study and were the basis for analysis. The Q-SRP group was scaled quadrant-wise at 1-week intervals. The other groups received a one-stage full-mouth scaling with (FMD) and without (FM-SRP) chlorhexidine. At baseline, after 1, 2, 4 and 8 months clinical parameters were recorded and microbiological analysis was performed. RESULTS: All three treatment modalities resulted in significant clinical improvement at any time. There were only group differences after 1 and 2 months: in the FM-SRP group was a significantly higher reduction of probing depth and bleeding on probing compared with the other two groups. The bacteria could be reduced in every group although this reduction was only significant for Prevotella intermedia in the FMD group 8 months after treatment. CONCLUSION: All three treatment modalities lead to an improvement of the clinical and microbiological parameters, however, without significant group differences after 8 months.

Osseointegrated implants in subjects treated for generalized aggressive periodontitis: 10-year results of a prospective, long-term cohort study.

BACKGROUND: The aim of this prospective 10-year study of partially edentulous subjects treated for generalized aggressive periodontitis and periodontally healthy subjects was a clinical, microbiologic, and radiographic comparison of teeth and implants and assessment of the implants' success rate. METHODS: Five subjects treated for generalized aggressive periodontitis (GAgP) and five periodontally healthy subjects who were orally rehabilitated with osseointegrated implants participated in the study. First, they were examined 2 to 4 weeks before extraction of the non-retainable teeth (baseline) and 3 weeks after insertion of the final abutments. All further examinations were performed during a 3-month recall schedule over a 10-year period. At every session, clinical parameters were recorded, and the composition of the subgingival microflora was determined. Radiographs were taken at baseline after insertion of the superstructure and 1, 3, 5, 8, and 10 years later. RESULTS: Throughout the follow-up period, the peri-implant gingival index of GAgP subjects was significantly higher than in periodontally healthy subjects. There was no difference in plaque index between teeth and implants or between the two groups. The peri-implant probing depths were comparable in the two groups and remained < or =4 mm throughout the follow-up. The probing depth was significantly higher around the teeth of the GAgP subjects compared to periodontally healthy subjects. Implants of GAgP subjects showed a significantly higher attachment loss (Ø 2.4 mm). The attachment level at teeth and implants of the periodontally healthy subjects and at teeth of the GAgP subjects was almost unchanged. Microbiologically, GAgP subjects had fewer cocci and more motile rods and filaments at teeth and implants than periodontally healthy subjects. GAgP subjects showed significantly more peri-implant bone loss in the first year (Ø 2.07 mm) and in the subsequent 9 years (total 1.3 mm). Bone loss at teeth also was significantly higher at baseline (Ø 26.39%) and in the following years (total 9.3%). Implant survival rates were 100% in periodontally healthy subjects versus 83.33% in GAgP subjects. CONCLUSIONS: This 10-year study showed that partially edentulous subjects treated for GAgP can be rehabilitated successfully with osseointegrated implants. However, the bone and attachment loss at the implants were higher than in periodontally healthy subjects.

Periodontal microbiota in patients with coronary artery disease measured by real-time polymerase chain reaction: a case-control study.

BACKGROUND: Recent data have shown that periodontal disease may increase the risk of occurrence of coronary heart disease in which inflammation initiated by bacteria and their compounds might be a common causal factor. This case-control study aimed at studying the relationship between periodontal disease and coronary artery disease (CAD) based on clinical and periodontal microbiologic parameters. METHODS: A total of 90 male subjects, 48 to 80 years of age, were included in this study. Forty-five men had CAD (CAD+), which was confirmed by coronary angiography. Forty-five age-matched controls showed no history or symptoms of CAD (CAD-). All subjects underwent a clinical periodontal examination including assessment of tooth loss, probing depth, clinical attachment level, and bleeding on probing. In the CAD+ group, this examination took place 1 day before coronary angiography. Subgingival microbial samples were taken and evaluated by means of real-time polymerase chain reaction (RT-PCR) for the total amount of bacteria and the following periodontopathogens: Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Parvimonas micra (formerly Micromonas micros), Dialister pneumosintes, and Campylobacter rectus. RESULTS: Compared to control subjects, CAD+ subjects had significantly deeper pockets (2.28 mm versus 2.96 mm; P <0.001) and greater attachment loss (2.85 mm versus 3.65 mm; P <0.001), and this difference remained statistically significant after adjusting for smoking. No significant differences were observed between cases and controls with regard to the number of teeth present. P. intermedia was the only periodontal pathogen that showed significantly higher mean counts in CAD+ subjects compared to CAD- subjects. Higher counts of total bacteria, P. micra, D. pneumosintes, and C. rectus were found in the CAD- group. CONCLUSION: The results suggest that a relationship between periodontal disease and coronary heart disease exists, although P. intermedia was the only periodontopathogen related to CAD.

A telescopic crown concept for the restoration of partially edentulous patients with aggressive generalized periodontitis: a 3-year prospective longitudinal study.

This prospective longitudinal 3-year study compared clinical parameters and implant success rates of removable superstructures supported by both teeth and implants in patients with treated generalized aggressive periodontitis (GAP) and of cemented, implant-retained fixed superstructures in periodontally healthy patients. A total of 17 partially edentulous patients with 54 implants took part in the study. Nine patients with treated GAP received removable superstructures according to the Marburg double crown system, and eight periodontally healthy patients received fixed superstructures. Teeth were examined 2 to 4 weeks before extraction of the nonretainable teeth (baseline) and 3 weeks after insertion of the definitive abutments. Every 3 months over a 3-year period, clinical parameters were recorded and the composition of the subgingival microflora was determined. Intraoral radiographs were obtained at baseline, just after insertion of the superstructure, and 1 and 3 years later. Both groups showed mean plaque and gingival indices below 0.43 at implants and teeth. Mean probing depths around implants increased by approximately 0.7 mm and remained virtually constant for the teeth. Mean attachment loss at implants was 0.9 mm in GAP patients and 0.5 mm in healthy patients. The morphologic distribution of microorganisms in both groups showed healthy conditions. Moderate bone loss at teeth and implants was registered. Implant success rates were 100% in the healthy patients and 97.6% in the GAP patients. No significant differences were seen in the results between the groups.

Digital volume tomography in the diagnosis of peri-implant defects: an in vitro study on native pig mandibles.

BACKGROUND: The aim of this study of native pig mandibles was to investigate the accuracy and quality of the representation of peri-implant defects by intraoral radiography (IR), panoramic radiography (PR), computer tomography (CT), and digital volume tomography (DVT). METHODS: The examination was carried out on 19 native pig mandibles. In the toothless sections of the mandibles, one or two implants were inserted. Following the standardized preparation of peri-implant defects (11 each of dehiscences, fenestrations, and 2- to 3-walled intrabony defects), IR, PR, CT, and DVT were performed. The peri-implant defects were measured using appropriate software on the digitized IR and PR image programs. As a control method, the peri-implant bone defects were measured directly using a reflecting stereomicroscope with measuring ocular. The statistical comparison between the measurements of the radiographic scans and those of the direct readings of the peri-implant defects was performed with Pearson's correlation coefficient. The quality of the radiographic scans was determined through the subjective perception and detectability of the peri-implant defects by five independent observers. RESULTS: In the DVT and CT scans, it was possible to measure all the bone defects in three planes. Comparison with the direct peri-implant defect measurements yielded a mean deviation of 0.17+/-0.11 mm for the DVT scans and 0.18+/-0.12 mm for the CT scans. On the IR and PR images, the defects could be detected only in the mesio-distal and cranio-caudal planes. In comparison with the direct measurements of the peri-implant defects, the IR images revealed a mean deviation of 0.34+/-0.30 mm, and the PR images revealed a mean deviation of 0.41+/-0.35 mm. The quality rating of the radiographic images was highest for the DVT scans. CONCLUSIONS: Overall, the CT and DVT scans displayed only a slight deviation in the extent of the peri-implant defects. Both radiographic imaging techniques permitted imaging of peri-implant defects in three planes, true to scale, and without overlay or distortion. The DVT scans showed the best imaging quality.

Bioabsorbable membrane and bioactive glass in the treatment of intrabony defects in patients with generalized aggressive periodontitis: results of a 5-year clinical and radiological study.

BACKGROUND: The aim of this clinical and radiological prospective 5-year study was to compare the long-term effectiveness of a bioabsorbable membrane and a bioactive glass in the treatment of intrabony defects in patients with generalized aggressive periodontitis. METHODS: Sixteen patients (11 women and five men) with generalized aggressive periodontitis were enrolled in the study. The investigations were confined to 1- to 3-walled intrabony defects with a depth >/=4 mm and with preoperative probing depths (PDs) >/=7 mm. Teeth with furcation involvement were excluded. Twenty-two of the defects were treated with the membrane (RXT group) and 20 with the bioactive glass (PG group). Allocation to the two groups was randomized. The clinical parameters plaque index (PI), gingival index (GI), PD, bleeding on probing (BOP), gingival recession (GR), clinical attachment level (CAL), and tooth mobility were recorded before surgery and at 6 months and every year for 5 years after surgery. Intraoral radiographs were taken using a standardized paralleling technique at baseline and every year for 5 years. Statistical analysis was based on Kolmogorov-Smirnov and Wilcoxon signed-rank tests, analysis of covariance, and Spearman's bivariate correlation analysis. RESULTS: After 5 years, a reduction in PD of 3.6 +/- 0.8 mm (P = 0.016) and a gain in CAL of 3.0 +/- 2.0 mm (P = 0.01) were registered in the RXT group. There was a slight increase in GR by 0.6 +/- 1.4 mm (P = 0.334). In the PG group, a reduction in PD of 3.5 +/- 1.4 mm (P = 0.01) and a gain in CAL of 3.3 +/- 2.1 mm (P = 0.01) were recorded, whereas GR increased by 0.2 +/- 1.7 mm (P = 0.525). The 1-, 2-, 3-, and 4-year results did not differ significantly from the 5-year results. Radiographically, the defects (the point on the proximal surface of the defective tooth at which the projected alveolar crest intersected the root surface [xCA] to the most coronally located point at the proximal surface of the tooth on the defect side up to which the periodontal ligament space still displayed a uniform width [xBD]) were found to be filled by 47.5% +/- 38.3% (P = 0.001) in the RXT group and by 65.0% +/- 50.5% (P = 0.001) in the PG group. Crestal resorption (the most apical point of the enamel at the proximal surface of the tooth on the defect side [xCEJ] to the xCA) was 19.0% +/- 30.2% (P = 0.374) in the RXT group and 12.3% +/- 38.6% (P = 0.647) in the PG group. The xCEJ to the xBD was significantly more in the PG group (28.4 +/- 24.6 versus 7.3 +/- 21.8, P = 0.048). A good standard of oral hygiene and inflammation-free periodontal tissue in the postoperative phase improved the treatment outcome. No dependence of attachment gain was found on the tooth type, number of walls involved in the defects (r = 0.075; P = 0.319), or intraoperative depth (r = 0.114; P = 0.307). CONCLUSIONS: Highly significant improvements in the parameters PD and CAL were recorded after 5 years with both regenerative materials. Radiographically, the defects (the xCED to the xBD) were found to be filled significantly more in the bioactive glass group. A good standard of oral hygiene and inflammation-free periodontal tissue in the postoperative phase improved the treatment outcome.

Implants in patients treated for generalized aggressive and chronic periodontitis: a 3-year prospective longitudinal study.

BACKGROUND: The aim of the present prospective longitudinal study of periodontally diseased and periodontally healthy patients was a clinical, microbiological, and radiographic comparison of teeth and implants and an assessment of the implant success rate. METHODS: Thirty-nine partially edentulous patients provided with a total of 150 implants were enrolled in the study. Oral rehabilitation was undertaken in 15 patients treated for generalized aggressive periodontitis (GAgP), 12 patients treated for generalized chronic periodontitis (GCP), and 12 periodontally healthy patients. The examinations of the teeth and implants were carried out within the framework of a 3-month recall schedule over a 3-year period. At each session, clinical parameters for probing depth (PD), gingival recession (GR), attachment level (AL), gingival index (GI), and plaque index (PI) were recorded, and the composition of the subgingival microflora determined by dark-field microscopy. In the periodontally diseased patients, Actinobacillus actinomycetemcomitans (A.a.), Porphyromonas gingivalis (P.g.), and Prevotella intermedia (P.i.) were detected at teeth and implants by DNA analysis in the first and third years after insertion of the superstructure. Intraoral radiographs of the teeth and implants were taken at baseline, immediately after insertion of the superstructure, and then 1 and 3 years later. RESULTS: The GI and PI at implants and teeth remained below 0.25 and 0.6, respectively, in all patient groups throughout the study period. At the implants and teeth, a slight increase in PD and a continuous attachment loss was recorded in the GAgP patients. The attachment loss was greater at the implants than at the teeth in all groups. The morphological distribution of the microorganisms revealed virtually healthy conditions in all groups. A.a. was detected in two GAgP patients, whereas P.g. and P.i. were found more frequently both in the GAgP and in the GCP patients. Radiographically detected bone loss was higher after 3 years at implants and teeth in the GAgP patients than in the other two groups. The implant success rates recorded were 100% in the periodontally healthy and GCP patients, and 95.7% in the maxilla and 100% in the mandible of the GAgP patients. CONCLUSIONS: The results show that oral rehabilitation can be performed with implants in patients treated for generalized aggressive and chronic periodontitis. However, slight attachment loss and bone loss were registered at the implants and teeth in the patients with aggressive periodontitis.

Digital volume tomography in the diagnosis of periodontal defects: an in vitro study on native pig and human mandibles.

BACKGROUND: The aim of this study of native pig and human mandibles was to investigate the accuracy and quality of the representation of periodontal defects by intraoral radiography (IR), panoramic radiography (PR), computed tomography (CT), and digital volume tomography (DVT) in comparison with histologic specimens. METHODS: Following the standardized preparation of periodontal defects (14 dehiscences, fenestrations, 2- to 3-walled intrabony defects, respectively; Class I, II, and III furcation involvement) in six pig and seven human mandibles, IR, PR, CT, and DVT were performed. The histologic specimens were produced by cutting blocks with the individual defects out of the mandibles, embedding them in acrylic, and producing sagittal and axial microsections. The intrabony defects were measured using appropriate software on the digitized IR and PR images programs. The histologic sections were measured by reflecting stereomicroscopy. The statistical comparison between the measurements of the radiographic images and those of the histologic specimens was performed with Pearson's correlation coefficient. The quality of the radiographic images was determined through the subjective perception and detectability of the intrabony defects by five independent observers. RESULTS: All intrabony defects could be measured in three planes in the CT and DVT scans. Comparison with the histologic specimens yielded a mean deviation of 0.16 +/- 0.10 mm for the CT scans and 0.19 +/- 0.11 mm for the DVT scans. On the IR and PR images, the defects could be detected only in the mesio-distal and craniocaudal planes. In comparison with the histologic specimens, the IR images revealed a mean deviation of 0.33 +/- 0.18 mm and the PR images a mean deviation of 1.07 +/- 0.62 mm. The quality rating of the radiographic images was highest for the DVT scans. CONCLUSIONS: Overall, the CT and DVT scans displayed only a slight deviation in the extent of the periodontal defects in comparison with the histologic specimens. Both radiographic imaging techniques permitted imaging of anatomic osseous structures in three planes, true to scale, and without overlay or distortion. The DVT scans showed the best imaging quality.

Real-time polymerase chain reaction for detection and quantification of bacteria in periodontal patients.

BACKGROUND: Accurate laboratory tests for the detection and quantification of periodontopathogens in subgingival plaque samples of periodontal disease patients are becoming essential to study the pathogenesis of this polymicrobial condition. We used a real-time polymerase chain reaction (PCR) assay for the quantification of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Dialister pneumosintes, Campylobacter rectus, and Micromonas micros as well as total eubacteria in subgingival plaque samples from individuals with periodontitis. METHODS: Eighty-three subgingival samples from periodontally diseased patients and 43 samples from periodontally healthy subjects were tested and the results of bacterial quantification were correlated to clinical parameters. Quantification was performed with specific 16S rRNA target sequences with double fluorescence labeled probes and serial dilutions of plasmid standards by real-time PCR. RESULTS: Results showed that patients as well as healthy subjects were positive for the presence of target periodontopathogens; however, median values were higher in samples from periodontitis subjects. In addition, a positive association was observed between colonization at high levels by P. gingivalis and M. micros and the presence of deep periodontal pockets. CONCLUSION: Real-time PCR provides a reliable high-throughput method for quantification of periodontopathogens and may be useful for understanding the complex etiology observed in periodontal diseases.

Implants in regenerated bone in patients treated for generalized aggressive periodontitis: a prospective longitudinal study.

The aim of this prospective longitudinal study of patients treated for generalized aggressive periodontitis (GAP) was the clinical, microbiologic, and radiologic longitudinal evaluation of implants placed into bone regenerated by the guided bone regeneration (GBR) technique. Ten patients with GAP who had lost either one or two maxillary incisors or premolars through periodontal disease and whose alveolar bone was neither high nor wide enough for implant placement were enrolled in the study. GBR was carried out in a two-stage procedure using titanium-reinforced extended polytetrafluoroethylene membranes and titanium screws. No bone graft or bone substitute materials were used. After 6 to 8 months, the membranes and supporting screws were removed, and a total of 15 implants (Nobel Biocare) were placed. The control group comprised 10 periodontally healthy patients who had a total of II implants (Nobel Biocare) placed in the maxilla (incisor and premolar region) without GBR because of aplasia, trauma, or endodontic lesions. All patients were examined 2 to 4 weeks before extraction of the nonretainable teeth (baseline) and again immediately after placement of the superstructure. Further examinations were performed within the framework of a 3-month recall schedule over a 3-year period. At each session, clinical parameters (probing pocket depths, bleeding on probing, gingival recession, clinical attachment level, Gingival Index, and Plaque Index) were recorded at teeth and implants, and the composition of the subgingival microflora was determined by dark-field microscopy and DNA probe. Intraoral radiographs were taken for control purposes at baseline, immediately after insertion of the superstructure, and 1 and 3 years later. The GBR technique yielded a horizontal and vertical bone gain of 4.5 to 7.0 mm in the GAP patients. The clinical, microbiologic, and radiologic findings indicated healthy periodontal and periimplant conditions in both patient groups throughout the study. However, a slightly increased attachment loss (0.65 mm) and bone loss (1.78 mm) were recorded at the implants in the regenerated bone after 3 years of loading. The 3-year implant survival rate was 100% in both groups. The possibility of continuous attachment loss and bone loss occurring at teeth and implants in regenerated bone cannot be ruled out in patients treated for aggressive periodontitis. The prognosis for the retention of the teeth and implants is thus open to question.

Bioabsorbable membrane and bioactive glass in the treatment of intrabony defects in patients with generalized aggressive periodontitis: results of a 12-month clinical and radiological study.

BACKGROUND: Guided tissue regeneration can be achieved using membranes. In recent years, some evidence has been provided that bioactive glass is also capable of supporting the regenerative healing of periodontal lesions. The aim of this clinical and radiological prospective study was to compare the effectiveness of a bioabsorbable membrane and a bioactive glass in the treatment of intrabony defects in patients with generalized aggressive periodontitis. METHODS: Twelve patients (9 females, 3 males) with generalized aggressive periodontitis were enrolled in the study. The investigations were confined to 1- to 3-walled intrabony defects with a depth > or = 4 mm and with preoperative probing depths > or = 7 mm. Teeth with furcation involvement were excluded. Fifteen of the total 30 defects were treated with the membrane (RXT group) and 15 with the bioactive glass (PG group). Allocation to the groups was randomized. The clinical parameters plaque index (PI), gingival index (GI), probing depth (PD), bleeding on probing (BOP), gingival recession (GR), clinical attachment level (CAL), and mobility were recorded prior to surgery as well as 6 and 12 months after surgery. Intraoral radiographs were taken in standardized paralleling technique at baseline and 12 months after the surgery. Following digitization, changes in the distances from the alveolar crest (xCA) to the defect base (xBD) and from the CEJ (xCEJ) to the xCA were determined. Statistical analysis was based on Kolmogorov-Smirnov test, Wilcoxon signed-ranks test, analysis of covariance, and Spearman's bivariate correlation analysis. RESULTS: After 12 months, a reduction in PD of 4.0 +/- 2.1 mm (P < 0.001) and a gain in CAL of 3.4 +/- 2.3 mm (P < 0.001) was registered in the RXT group. There was a slight increase in GR by 0.6 +/- 1.5 mm (P = 0.074). In the PG group, a reduction in PD of 3.8 +/- 1.9 mm (P < 0.001) and a gain in CAL of 2.8 +/- 1.9 mm (P < 0.001) was recorded, whereas GR increased by 1.0 +/- 1.4 mm (P = 0.007). The 6-month results did not differ significantly from the stated values. Radiographically, the defects (xCA to xBD) were found to be filled by 57.2 +/- 33.5% (P = 0.001) in the RXT group and by 50.5 +/- 22.8% (P = 0.001) in the PG group. Crestal resorption (xCEJ to xCA) was 6.1 +/- 34.5% (P = 0.910) in the RXT group and 15.1 +/- 39.7% (P = 0.433) in the PG group. Only the change in gingival recession after 12 months was significantly greater (P = 0.031) in the PG group, with -1.0 +/- 1.4 mm, compared to the RXT group, with -0.6 +/- 1.5 mm. Changes in the other clinical and radiological parameters showed no significant differences. The attachment gain correlated negatively with the preoperative PI (r = -0.574; P = 0.004) and with BOP after 6 months (r = -0.315; P = 0.021). CONCLUSIONS: Highly significant improvements in the parameters PD, CAL, and xCA-xBD were recorded after 6 and 12 months, respectively, with both regenerative materials. A good standard of oral hygiene and inflammation-free periodontal tissue in the postoperative phase improved the treatment outcome.

Detection of Porphyromonas gingivalis DNA in aortic tissue by PCR.

BACKGROUND: Periodontopathogens may play a role in the etiology of cardiovascular disease. The aim of the present study was to investigate biopsies of aortic tissue for the presence of periodontopathogens. METHODS: Samples taken from the aortas of 26 patients connected to a heart-lung machine during open-heart surgery were analyzed in a gene-diagnostics laboratory by polymerase chain reaction. Immediately after biopsy, the samples were transferred into liquid nitrogen and stored at -80 degrees C. 16S rRNA gene-directed primers were used for general detection of bacterial cells, and specific primers for detection of Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans. Questionable amplificons were verified by Southern hybridization using DNA probes. RESULTS: Bacterial DNA was found in 23 of 26 (88.5%) samples, in most cases only in concentrations around the detection limit. Four samples were clearly positive for P. gingivalis; A. actinomycetemcomitans was not detected. CONCLUSION: These results might indicate a link between periodontopathogens entering the cardiovascular system and cardiovascular disease.

The treatment of uncoated and titanium nitride-coated abutments with different instruments.

PURPOSE: The aim of this in vitro study of titanium abutments was to investigate the extent of treatment traces, the roughness depth, and the quantity of titanium or, in the case of coated abutments, titanium nitride (TiN) removed from the surface after treatment with various instruments. MATERIALS AND METHODS: Eleven uncoated, mechanically smoothed abutments and 11 TiN-coated abutments were used. The abutments were treated with titanium, steel, and plastic curettes; a rubber cup; an ultrasonic scaler with a steel tip; and an air scaler and cleaning powder. There were two 2 x 2-mm test fields on each abutment; each was subjected to standardized treatment with an instrument. The untreated surfaces of each abutment served as controls. The roughness depth (Rz) and profile height of treated and untreated surfaces were measured with a profilometer; profile height served as a basis for determining the amount of substance removed by treatment. The treatment traces were analyzed by scanning electron microscopy and light microscopy. RESULTS: Both the ultrasonic scaler and the steel and titanium curettes left pronounced traces on the uncoated abutments and increased Rz. Substantial substance removal was recorded following the use of the ultrasonic scaler (17.57 +/- 2.87 microm) and the steel curettes (8.48 +/- 2.81 microm) on the uncoated abutments. In tests of the coated abutments, measurable substance removal (4.80 +/- 0.99 microm) and increased roughness depth were noted only with use of the steel curettes. The treatment traces left by the other instruments were distinctly less pronounced than on the uncoated abutments. Light microscopy revealed detachment of the TiN coating after use of the ultrasonic scaler, titanium curettes, and steel curettes. Slight to moderate treatment traces were recorded after use of the rubber cup; no substance removal was observed. On the TiN-coated abutments, only slight treatment traces, if any, were recorded, and there was no substance removal. A planing effect (ie, an Rz decrease of 66.4%) was observed. The plastic curette and the air scaler caused no damage to the titanium or TiN surfaces. DISCUSSION AND CONCLUSION: The TiN-coated abutments displayed fewer treatment traces, less roughness depth, and less substance removal after being treated with various instruments. Two concerns, however, are the detachment of the coating after only few actions with steel and titanium curettes or with an ultrasonic scaler with steel tip, and the greater initial roughness depth of coated implants.

A telescopic crown concept for the restoration of partially edentulous patients with aggressive generalized periodontitis: two case reports.

Osseointegrated implants have been used with outstanding success in periodontally healthy patients in recent years and have thus become an established part of prosthetic treatment. Whereas initial reports were confined to their use in edentulous patients, in particular in the mandibular area, first results on their application in the oral rehabilitation of partially edentulous patients were published in the mid-1980s. Whether the positive results reported in periodontally healthy patients are also applicable to patients with progressive periodontal disease has yet to be clarified. As only a few controlled longitudinal studies dealing with the success of implants in periodontally involved patients have been published to date, detailed case reports are of great importance.

Mucositis, peri-implantitis, implant success, and survival of implants in patients with treated generalized aggressive periodontitis: 3- to 16-year results of a prospective long-term cohort study.

BACKGROUND: The aim of this prospective study is to evaluate the prevalence of mucositis, peri-implantitis, implant success, and survival in partially edentulous patients treated for generalized aggressive periodontitis (GAgP) and in periodontally healthy individuals. METHODS: Thirty-five patients treated for GAgP and 18 periodontally healthy patients orally rehabilitated with osseointegrated implants participated in the study. They were first examined 2 to 4 weeks before extraction of the non-retainable teeth (baseline) and 3 weeks after insertion of the final abutments. Additional examinations were performed during a 3-month recall schedule over a 5- to 16-year period (mean, 8.25 years). At every session, clinical parameters were recorded. At 1, 3, 5, 10, and 15 years after insertion of the superstructure, a microbiological and radiographic examination was performed. RESULTS: The results show implant survival rates of 100% in periodontally healthy individuals versus 96% in GAgP patients. The implant success rate was 33% in GAgP patients and 50% in periodontally healthy individuals. In GAgP patients, mucositis was present in 56% and peri-implantitis in 26% of the implants. In periodontally healthy individuals, 40% of the implants showed mucositis and 10% peri-implantitis. GAgP patients had a five times greater risk of implant failure, a three times greater risk of mucositis, and a 14 times greater risk of peri-implantitis. CONCLUSION: These results suggest that patients with treated GAgP are more susceptible to mucositis and peri-implantitis, with lower implant survival and success rates.

Interactions between stress, interleukin-1beta, interleukin-6 and cortisol in periodontally diseased patients.

BACKGROUND/AIMS: The aim of the present study was to measure interleukin-1beta, interleukin-6 and cortisol levels in the peripheral blood of periodontally diseased patients in order to record any interactions with psychosocial stress. MATERIAL AND METHODS: The test group comprised 16 patients with untreated and 14 with treated aggressive generalized periodontitis (AGP), five patients with untreated aggressive localized periodontitis (ALP) and five with chronic generalized periodontitis (CGP). The control group comprised 40 periodontally healthy probands. Blood was taken from the cephalic vein of all patients and controls at the same time (8 a.m.) each day. IL-1beta, IL-6 and cortisol levels were then measured with a sensitive ELISA, the 'Quantikine HS Immunoassay Kit' (Biermann Diagnostica, Bad Nauheim, FRG). The clinical examination covered probing depth, gingival recession, gingival index, plaque index and clinical attachment level. A questionnaire was used to ask the patients and controls about their attitude to life and the stress induced by their jobs and their families. Previous and current levels of tobacco consumption were also recorded. Statistical evaluation was based on the Mann-Whitney U-Wilcoxon test for comparison of blood serum values and clinical parameters between patients and controls, and the Kruskal-Wallis test for intergroup comparison. All data were correlated by means of Spearman's rank correlation coefficient, and significance levels relating to stress and smoking were determined with the chi-square test. RESULTS: With respect to cortisol, the results showed no significant differences either between the patient groups or in comparison with the controls. IL-1beta was detected only in the AGP patients and their controls, but with no significant differences. IL-6 was detected in virtually all patients and controls, but with no significant differences. Only in the untreated AGP patients was IL-6 significantly elevated (P < 0.05) and a slight correlation with attachment loss recorded. In all AGP patients a slight correlation between IL-1beta and IL-6 was recorded. Evaluation of the questionnaire revealed a higher proportion of untreated AGP patients than of controls with a pessimistic attitude to life. In all AGP patients, family-induced stress and smoking were found to correlate with attachment loss. In the untreated AGP patients, smoking correlated with IL-1beta protein content, and in the controls there was a moderate correlation between smoking and IL-6 levels. CONCLUSIONS: The present study found no correlation between the immunological mediators (IL-1beta, IL-6), glucocorticoids (cortisol) and the registered stress values. However, the patients with untreated AGP showed signs of a pessimistic attitude to life, and an elevated IL-6 level was recorded in the peripheral blood. As a restrictive factor it should be borne in mind that the number of patients investigated was too small for adequate conclusions to be drawn.

DNA from periodontopathogenic bacteria is immunostimulatory for mouse and human immune cells.

Although bacterial DNA (bDNA) containing unmethylated CpG motifs stimulates innate immune cells through Toll-like receptor 9 (TLR-9), its precise role in the pathophysiology of diseases is still equivocal. Here we examined the immunostimulatory effects of DNA extracted from periodontopathogenic bacteria. A major role in the etiology of periodontal diseases has been attributed to Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Peptostreptococcus micros. We therefore isolated DNA from these bacteria and stimulated murine macrophages and human gingival fibroblasts (HGF) in vitro. Furthermore, HEK 293 cells transfected with human TLR-9 were also stimulated with these DNA preparations. We observed that DNA from these pathogens stimulates macrophages and gingival fibroblasts to produce tumor necrosis factor alpha and interleukin-6 in a dose-dependent manner. Methylation of the CpG motifs abolished the observed effects. Activation of HEK 293 cells expressing TLR-9 which were responsive to bDNA but not to lipopolysaccharide confirmed that immunostimulation was achieved by bDNA. In addition, the examined bDNA differed in the ability to stimulate murine macrophages, HGF, and TLR-9-transfected cells. DNA from A. actinomycetemcomitans elicited a potent cytokine response, while DNA from P. gingivalis and P. micros showed lower immunostimulatory activity. Taken together, the results strongly suggest that DNA from A. actinomycetemcomitans, P. gingivalis, and P. micros possesses immunostimulatory properties in regard to cytokine secretion by macrophages and fibroblasts. These stimulatory effects are due to unmethylated CpG motifs within bDNA and differ between distinct periodontopathogenic bacteria strains. Hence, immunostimulation by DNA from A. actinomycetemcomitans, P. gingivalis, and P. micros could contribute to the pathogenesis of periodontal diseases.