Tooth survival and clinical outcomes up to 26 years after guided tissue regeneration therapy in deep intra-bony defects: Follow-up investigation of three randomized clinical trials.

AIM: To investigate tooth survival and clinical long-term outcomes up to 26 years following guided tissue regeneration (GTR) therapy in deep intra-bony defects. METHODS: Patients from three prospective clinical split-mouth studies, which investigated the outcomes of GTR therapy, were re-evaluated 21-26 years after surgery independent of the membrane type used, and tooth survival was assessed according to several site-specific and patient-related factors. RESULTS: About 50 patients contributing 102 defects were available for this long-term follow-up. After up to 26 years (median 23.3 years), 52.9% of the teeth were still in situ. The median survival of the extracted teeth was 13.8 years. Patients with diabetes mellitus and/or smoking history lost significantly more teeth in the long term. Compared to the 1-year situation, there was no new median CAL loss after up to 26 years in the teeth which were still in situ. CONCLUSIONS: Within the limitations of this study, our data show that more than 50% of the initially seriously diseased teeth were still in situ up to 26 years following GTR therapy despite an overall limited adherence to SPT. In the majority of these teeth, the CAL gain 1 year after GTR could be maintained over this long period.

Influence of autogenous platelet concentrate on combined GTR/graft therapy in intra-bony defects: A 13-year follow-up of a randomized controlled clinical split-mouth study.

AIM: To investigate the clinical long-term outcomes 13 years following guided tissue regeneration (GTR) in deep intra-bony defects with and without additional application of autogenous platelet concentrate (APC). METHODS: In 25 patients, two deep contra-lateral intra-bony defects were treated according to GTR using ß-TCP and bio-resorbable membranes. In test defects, APC was applied additionally. After 13 years, clinical healing results were assessed and compared to results at baseline and after 1 year. Furthermore, a tooth survival analysis was carried out. RESULTS: After 13 years, 22 patients were available for tooth survival analysis showing 81.8% of test and 86.4% of control teeth still in situ. Based on the 15 patients still available for split-mouth analysis, median CAL was 10.0 mm in test and 12.0 mm in control sites at baseline. After 1 year, both groups revealed significant CAL gains of 5.0 mm, followed by a new CAL loss of 1.0 mm in the following 12 years. There were no significant differences between test and control sites. CONCLUSION: Within the limits of this study, the data show that most of the CAL gain following GTR can be maintained over 13 years. The additional use of APC had no positive influence on the long-term stability.

Antimicrobial photodynamic therapy vs. local minocycline in addition to non-surgical therapy of deep periodontal pockets: a controlled randomized clinical trial.

OBJECTIVES: To investigate the additional influence of either antimicrobial photodynamic therapy (aPDT; Helbo® Photodynamic Systems) or local application of minocycline microspheres (MC; Arestin, OraPharma) on clinical and microbiological healing results in deep periodontal pockets (PPD ≥6 mm) following non-surgical periodontal therapy (SRP). MATERIALS AND METHODS: Forty-five patients with chronic periodontitis were evaluated: test group aPDT + SRP (n = 15), positive control group MC + SRP (n = 15), and negative control group SRP-alone (n = 15). Clinical and microbiological healing parameters were recorded in every patient for four experimental teeth at baseline, 6 weeks, and 3, 6, and 12 months. Wilcoxon signed-rank test and Mann-Whitney U test were used for statistical analysis (α = 0.05). RESULTS: Significant improvements in clinical and microbiological parameters were found for all groups after 6 weeks and 3, 6, and 12 months. Differences between groups were not statistically significant. Changes after 12 months [median (25/75%)] are as follows: reduction in PPD [mm]: aPDT + SRP 2 (1/3), MC + SRP 3 (1/4), SRP-alone 2 (1/3); percentage of residual BOP positive teeth [%]: aPDT + SRP 75 (25/100), MC + SRP 33.3 (0/50), SRP-alone 66.7 (25/75). CONCLUSIONS: Within the limitations of this study, neither the applied aPDT system nor MC showed a significant additional influence on clinical and microbiological healing outcomes in deep periodontal pockets compared to SRP alone. CLINICAL RELEVANCE: In deep periodontal defects, the efficacy of non-surgical periodontal treatment seems not to be improved by adjunctive use of antimicrobial photodynamic therapy or minocycline microspheres.

Influence of autogenous platelet concentrate on combined GTR/graft therapy in intrabony defects: a 7-year follow-up of a randomized prospective clinical split-mouth study.

OBJECTIVES: To investigate the influence of autogenous platelet concentrate (APC) on the long-term regeneration outcome 7 years after guided tissue regeneration (GTR) in deep intrabony periodontal defects. MATERIAL AND METHODS: In 25 patients, two deep contra-lateral intrabony defects were treated according to GTR (randomized split-mouth-design). In the test defects, APC was additionally applied. After 7 years, healing results were assessed clinically by a blinded examiner and compared to baseline and 12-months results. Furthermore, a tooth survival analysis was performed. RESULTS: After 7 years, 23 patients were available for survival analysis and 16 patients for split-mouth analysis; 84% of the test and control teeth were still in situ. In both groups, the median attachment level of 10.5 mm [(25/75%): test 9.0/13.0, control 10.0/12.0] at baseline was significantly (p ≤ 0.05) reduced to 6.0 mm [test 4.0/6.8, control 5.0/7.0] after 1 year. Six years later, it had increased again to 7.0 mm in test sites [5.3/10.0] (p ≤ 0.05) and had remained stable in control sites [5.0/7.8] (p > 0.05). Bleeding on Probing (BOP) had increased in both groups. During the last 6 years, only 26% of the patients received a structured supportive periodontal therapy in the clinic. CONCLUSION: Within its limitations, the present study indicates that the clinical outcome of GTR therapy can be maintained over 7 years. However, the additional use of APC may even have a possibly negative influence on the long-term stability.

Prevalence of OPG and IL-1 gene polymorphisms in chronic periodontitis.

AIM: To investigate the association of polymorphisms in the osteoprotegerin (OPG) and interleukin 1 (IL-1) genes with chronic periodontitis (CP). MATERIAL AND METHODS: One hundred and ninety-four individuals (97 CP patients, 97 controls) were genotyped for the OPG polymorphisms Lys3Asn and Met256Val and for the IL-1 polymorphisms IL-1A (-889C/T) and IL-1B (+3953C/T). RESULTS: The homozygous variants coding for Lys3 were present at a higher frequency, whereas Asn3 and Met256 were present at a lower frequency in CP patients/controls (Lys3: 31%/25%, Asn3: 23%/32% and Met256: 66%/73%). Heterozygosity for Lys3Asn was observed at a higher frequency in CP patients/controls (46%/43%). Homozygosity for the Val256 genotype was observed in two CP patients (one in controls). Met256Val heterozygosity was more prevalent in CP patients/controls (32%/20%). All differences were statistically not significant between CP patients and controls. In contrast, both IL-1 polymorphisms were statistically significant. The heterozygous variant for IL-1A was present in 32% of the CP patients and in 20% of the controls (homozygosity (patients/controls) CC: 10%/21% and TT: 55%/33%). Heterozygosity for IL-1B was observed in 37% of the CP patients versus 34% in the controls (homozygosity (patients/controls) CC: 26%/57% and TT: 37%/9%). CONCLUSION: While the association between the IL-1 polymorphisms and CP was confirmed, no association between the OPG polymorphisms and CP could be found.

Extracellular matrix expression and periodontal wound-healing dynamics following guided tissue regeneration therapy in canine furcation defects.

AIM: Temporal and spatial expression pattern of extracellular matrix (ECM) components in furcation defects following guided tissue regeneration (GTR) compared with open-flap debridement (OFD). MATERIAL AND METHODS: In 21 dogs, mandibular second and fourth pre-molars were treated with one non-resorbable and three different resorbable membranes. Third pre-molars were treated by OFD. After 2, 4, 8 weeks and 3, 6, and 12 months, tissues were analysed by immunohistochemistry for collagen I (Col-I) and III (Col-III), fibronectin (FN), bone sialoprotein (BSP), and osteopontin (OPN). RESULTS: At 2 weeks, the defect was mainly occupied by FN+ granulation tissue (GT), which was sequentially replaced by new connective tissue expressing FN, Col-I, and increasingly Col-III. Following superficial resorptions by OPN+ osteoclasts and odontoclasts, cementum and bone formation ensued with strong expression of BSP and OPN along bone and tooth surfaces. Deposition of Col-I, FN, BSP and OPN+ cementoid and osteoid became evident after 4 weeks. Extrinsic fibres of cementum and bone stained intensely for Col-III. The newly formed periodontal ligament expressed FN, Col-I, and Col-III, but no BSP or OPN. CONCLUSIONS: The spatial ECM expression was similar for OFD and the different GTR methods, although the timing and quantity of ECM expression were influenced by wound stabilization and inflammatory reactions.