The adjunctive use of antimicrobial photodynamic therapy, light-emitting-diode photobiomodulation and ozone therapy in regenerative treatment of stage III/IV grade C periodontitis: a randomized controlled clinical trial.

OBJECTIVES: To assess the short-term efficacy of multiple sessions of antimicrobial photodynamic therapy (aPDT), light-emitting-diode (LED) photobiomodulation, and topical ozone therapy applications following surgical regenerative treatments on clinical parameters, patient-centered outcomes, and mRNA expression levels of VEGF, IL-6, RunX2, Nell-1, and osterix in gingival crevicular fluid samples in patients with stage III/IV, grade C periodontitis. MATERIALS AND METHODS: Forty-eight systemically healthy patients were assigned into four groups to receive adjunctive modalities with regenerative periodontal surgical treatment. A 970 ± 15 nm diode laser plus indocyanine-green for aPDT group, a 626 nm LED for photobiomodulation group, and topical gaseous ozone were applied at 0, 1, 3, and 7 postoperative days and compared to control group. The clinical periodontal parameters, early wound healing index (EHI), and postoperative patients' morbidity were evaluated. The mRNA levels of biomarkers were assessed by real-time polymerase chain reaction. RESULTS: No significant difference in the clinical parameters except gingival recession (GR) was identified among the groups. For group-by-time interactions, plaque index (PI) and probing pocket depths (PD) showed significant differences (p = 0.034; p = 0.022). In sites with initial PD > 7 mm, significant differences were observed between control and photobiomodulation groups in PD (p = 0.011), between control and aPDT, and control and photobiomodulation groups in CAL at 6-month follow-up (p = 0.007; p = 0.022). The relative osterix mRNA levels showed a statistically significant difference among the treatment groups (p = 0.014). CONCLUSIONS: The additional applications of aPDT and LED after regenerative treatment of stage III/IV grade C periodontitis exhibited a more pronounced beneficial effect on clinical outcomes in deep periodontal pockets.

Oral and dental alterations and growth disruption following chemotherapy in long-term survivors of childhood malignancies.

PURPOSE: More attention has been focused on the long-term side effects of treatment protocols since impressive advances in childhood cancer treatment have resulted in a growing population of patients. The purpose of this study was to investigate the disturbances of dento-facial development in children who were long-term survivors of childhood malignancies. METHODS: Fifty-three children (mean age, 10 years + 4 months) in long-term remission underwent oral/dental and radiographic examinations after completion of therapy. Crown and root malformations, gingival/periodontal status, enamel defects, discolorations, decayed and unerupted teeth, premature apexifications, agenesis, maximal interincisal opening and lateral movement of jaws, and soft tissue abnormalities were noted. Caries were evaluated by the decayed-missing-filled teeth (DMFT) index. Forty healthy children (mean age, 12 years + 4 months) belonging to the same age group and socioeconomic community were served as controls. All participants in the study were evaluated in terms of craniofacial development. RESULTS: The data of the study showed that higher prevalence of root malformation, unerupted teeth, and enamel hypoplasia were detected as a consequence of childhood cancer and/or antineoplastic therapy. Although no differences of craniofacial growth and development were observed between groups (P > 0.05), plaque and gingival index scores were statistically higher in the study group (P < 0.05). CONCLUSION: A range of variations in dental structures is recognized as a side effect of childhood cancer therapy in long-term survivors of pediatric malignancies that may affect their quality of life.

Identification of a Predictive Decision Model Using Different Data Mining Algorithms for Diagnosing Peri-implant Health and Disease: A Cross-Sectional Study.

PURPOSE: The aim of this study was to determine a predictive decision model for peri-implant health and disease and to reveal the highest accuracy of prediction using three different data mining methods. MATERIALS AND METHODS: This cross-sectional study included a total of 216 patients with 542 dental implants from the Periodontology Department of Gazi University. The implants were classified into peri-implant health, peri-implant mucositis, and peri-implantitis groups based on established clinical and radiographic assessments. Prediction models were created using clinical variables in combination with possible risk factors for peri-implant diseases. Different data mining methods (decision-tree [DT]; J48), logistic regression, and artificial neural network (multilayer perceptron [MLP]) were compared to yield a better predictive decision model based on predictor variables with the highest potential of effect. RESULTS: The prevalence of peri-implant mucositis and peri-implantitis among the participants of the specialist referral periodontal practice of the university was 36.1% (95% CI: 29.7 to 42.5) and 34.7% (95% CI: 28.4 to 41.0) at the patient level, respectively. The J48 method revealed a higher prediction of peri-implant health and disease with an accuracy of 0.871 compared with the logistic regression and MLP methods (0.832 and 0.852, respectively) for the present data set. In this specific patient population, the J48 model revealed the top-level node as "bleeding on probing (BOP)." "Maintenance therapy" and "medication use" were noted as powerful predictors in the next split-levels. CONCLUSION: The J48 model presented an acceptable predictive accuracy of peri-implant health and disease. The model revealed BOP as a major predictive clinical parameter when evaluated with possible risk factors for this patient population.

Platform-switched implants vs platform-matched implants placed in different implant-abutment interface positions: A prospective randomized clinical and microbiological study.

BACKGROUND: Placement of the implant-abutment interface (IAI) away from the bone crest has been suggested to have positive impacts on maintenance of peri-implant tissues. PURPOSE: To assess the effects of platform-switched and platform-matched implants, taking into consideration the IAI at different positions relative to the bone crest, on clinical, radiographic, and microbiological outcomes during 12 months following functional loading. MATERIALS AND METHODS: The present prospective randomized study was performed upon 70 patients. Group I (n = 23) implants presenting a platform-switched implant-abutment connection design was inserted 1 mm subcrestally. Group II (n = 22) implants with similar properties were inserted crestally. Group III (n = 25) implants presenting a platform-matched approach with an internal hexagon connection design was inserted crestally. The periodontal parameters were assessed at baseline, and 3, 6, and 12 months postloading. Radiographic marginal bone level (MBL) changes were analyzed at the 12-month follow-up. The amount of DNA copies of Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Provetalla intermedia and total bacterial mean load in peri-implant sulcus fluid (PISF) were assessed at the same periods. RESULTS: There were no significant differences among the groups with respect to the periodontal parameters for all time periods. At 12-month follow-up, the MBL changes were 0.16 ± 0.29 mm and 0.17 ± 0.23 mm for group I, 0.15 ± 0.25 mm and 0.17 ± 0.26 mm for group II, 0.17 ± 0.26 mm and for group III in mesial and distal sites, respectively. The mean total bacterial load was found significantly higher for group III compared to the other groups in the three interval times (P < .05). CONCLUSION: Implants restored with platform-switching and platform-matching performed equally regarding clinical and radiographic outcomes. Platform-matched implants inserted at the crestal level presented higher the mean bacterial total load in PISF.

Effects of decontamination and implant surface characteristics on re-osseointegration following treatment of peri-implantitis.

BACKGROUND: Although considerable bone fill may occur following treatment of peri-implantitis, re-osseointegration appears to be limited and unpredictable. OBJECTIVES: To evaluate the effects of various decontamination techniques and implant surface configurations on re-osseointegration of contaminated dental implants. MATERIAL AND METHODS: Three months after tooth extraction, implants consisting of a basal part and an exchangeable intraosseous implant cylinder (EIIC) were placed in the mandibles of dogs. The EIIC was machined (M), sandblasted and acid-etched (SLA), or titanium plasma sprayed (TPS). Ligature-induced peri-implantitis was initiated 8 weeks post-implantation and lasted until bone loss reached the junction of the two implant parts. Three treatment modalities were applied: (T1) the EIIC was exchanged for a pristine EIIC; (T2) the EIIC was sprayed in situ with saline; and (T3) the EIIC was removed, cleansed outside the mouth by spraying with saline, steam-sterilized, and remounted. A collagen barrier was placed over each fixture, and 3 months later, samples were processed for histology and histomorphometry. RESULTS: T2 revealed the highest bone-to-implant contact (BIC) level (significantly better than T1 and T3). T2 also yielded the highest bone crest level (significantly better than T1), followed by T3 (significantly better than T1). SLA showed the highest BIC level (significantly better than M), followed by TPS. There were no statistically significant differences in bone crest height between implant types. CONCLUSIONS: Both SLA implants and in situ cleansing resulted in the best re-osseointegration and bone fill of previously contaminated implants.

The chemical surface evaluation of black and white porous titanium granules and different commercial dental implants with energy-dispersive x-ray spectroscopy analysis.

BACKGROUND: The chemical surface structure of the porous titanium grafts has not been found to study in the literature on the similarity of chemical surfaces of different commercial dental implants. PURPOSE: The purpose of this study is to investigate the chemical composition and surface energies of white (WPTG) and black porous titanium granules (PTG) by energy dispersive x-ray spectrometry (EDX) analysis to compare with different commercial dental implant surface. MATERIALS AND METHODS: The surface chemical compositions of six commercially available dental implants with different surface structures, PTG and WPTG were examined by EDX analysis. Surface analyzes were performed on the apical, middle, and coronal parts of each implant and on the top, flank, and valley regions on each side. Surface analyzes of dental implants were evaluated at ×200 and ×2000 magnifications. The EDX evaluation of PTG grafts were evaluated at ×250, ×2000, ×5000, and ×50 000 magnifications. RESULTS: PTG grafts showed elements of Na (8.88 ± 9.98%), Cl (2.44 ± 1.96%), and Al (0.99 ± 0.37%) as well as Ti (90.06 ± 11.34%) molecule at ×5000 magnification. In WPTG, Ti (%34.55 ± 6.41%) and O (%65.44 ± 6.42%) molecules were detected. CONCLUSIONS: It has been found that PTG surface was not made of pure titanium, it has different chemical molecules at larger magnifications. Cell culture and experimental studies are needed to establish a relationship between the different commercial implants and the surface structure of the titanium granules.

The role of visfatin levels in gingival crevicular fluid as a potential biomarker in the relationship between obesity and periodontal disease.

OBJECTIVES: Visfatin is an adipokine that plays an important role in immune functions as a growth factor, enzyme, and pro-inflammatory mediator. We aimed to determine the levels of visfatin, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) in gingival crevicular fluid (GCF) in both obese/non-obese patients, with/without generalized chronic periodontitis (GCP). METHODOLOGY: Patients were categorized as obese (O) (n=31) or non-obese (nO) (n=19). Groups were divided into four subgroups according to periodontal conditions: (1) periodontally healthy without obesity (nO-Ctrl); (2) GCP without obesity (nO-CP); (3) periodontally healthy with obesity (O-Ctrl); and (4) GCP with obesity (O-CP). Demographic variables, anthropometric and laboratory data were recorded. Periodontal parameters were measured at baseline and 3rd months after either non-surgical periodontal treatment or calorie -restricted diet therapy. At the same time, GCF samples were taken from patients to analyze TNF-alpha, IL-6,and visfatin levels. RESULTS: Periodontal parameters were significantly higher in the O group than in the nO group (P<0.05). IL-6 levels were higher in the O group than in the nO group (P<0.001). The visfatin levels of the obese patients were reduceddecreased following the treatments (P<0.05). Cholesterol levels were higher in the O group than in the nO groups (P<0.05). IL-6 levels were higher in O-CP and O-Ctrl groups than in the nO-Ctrl group (P<0.05). Compared to the other groups, visfatin levels were significantly higher in the O-CP group but decreased following treatment (P<0.05). CONCLUSIONS: Our findings suggest that visfatin and IL-6 levels in GCF are associated with the pathogenesis of obesity and periodontitis. Within the limits of this study, we considered that there might be an association between the lipid profile and periodontitis on systemically healthy individuals.

An Evaluation of the Relationship Between Peri-implant Soft Tissue Biotype and the Severity of Peri-implantitis: A Cross-Sectional Study.

PURPOSE: This cross-sectional study aimed to analyze the relation between peri-implant soft tissue biotype (STB) and different levels of peri-implantitis severity, and to identify the possible risk indicators that affect the severity of peri-implantitis with regard to STB around dental implants. MATERIALS AND METHODS: Eighty-seven patients with 229 implants were diagnosed with peri-implantitis and recruited to the study. Clinical and radiographic parameters including Plaque Index (PI), probing depth (PD), bleeding on probing (BOP), gingival/mucosal recession (GR/MR), clinical attachment level (CAL), and marginal bone loss (BL) were analyzed. The periodontal status was assessed, and the levels of peri-implantitis severity were defined. These parameters were compared among the peri-implant STB groups (thick and thin biotype). To evaluate the effect of possible risk indicators on the levels of severity of peri-implantitis, univariate and multivariate logistic regression analyses were conducted for thick and thin biotype groups. RESULTS: The mean values of BOP, MR, CAL, and marginal BL were significantly lower for the thick group compared with the thin group (P < .05). For PI and PD values, no significant differences were found between the groups (P > .05). Moreover, multivariate analysis revealed statistically significant associations between peri-implantitis severity and the risk indicators maintenance therapy compliance and current periodontitis for the thin group (P < .05). CONCLUSION: The thin biotype could be more prone to increase in the severity of peri-implantitis. Maintenance therapy compliance and current periodontitis could be important risk indicators that affect the progression of the severity of peri-implantitis for implants where keratinized mucosa is thin or absent.

Ozone application as adjunctive therapy in chronic periodontitis: Clinical, microbiological and biochemical aspects.

BACKGROUND/PURPOSE: The application of ozone as an adjunctive treatment represents a new approach in the management of chronic periodontitis. The purpose of this study was to evaluate the clinical, biochemical and microbiological efficacy of ozone treatment as an adjunct to scaling and root planing (SRP) in generalized chronic periodontitis (GCP) patients. MATERIALS AND METHODS: Eighteen patients (9 males and 9 females; aged from 28 to 47 years, mean age of 40 ± 6.51 years) with GCP were recruited in the study. In a split mouth design, two quadrants in each patient were randomly allocated to SRP-alone or SRP-ozone therapy (SRP + OT) groups by coin toss method. Subgingival plaque and gingival crevicular fluid (GCF) samples were collected at baseline, following 1st and 3rd months. The clinical parameters were monitored at baseline and after 3 months. Microbiological parameters were analyzed by quantitative-PCR and GCF biomarkers were determined by ELISA. Results were analyzed statistically. RESULTS: Statistically significant improvements in all clinical parameters were accompanied by a reduction in microbiological and biochemical parameters in both treatment groups. SRP treatment resulted in a significant reduction of Porphyromonas gingivalis (Pg) at 1st month and Tannerella forsythia (Tf) and Prevotella intermedia (Pi) at 3 months. Following SRP treatment the interleukin (IL)-8 levels were significantly reduced at month 1. There were no significant differences between two treatments for any of the parameters. CONCLUSION: Within the limitations of this study, adjunctive ozone therapy did not provide additional benefits to clinical, microbiological and biochemical parameters over SRP in chronic periodontitis patients.

Copper deficiency with increased hematogones mimicking refractory anemia with excess blasts.

We describe a 19-year-old male patient with a previous diagnosis of familial Mediterranean fever (FMF), nephrotic syndrome and secondary amyloidosis, who presented with anemia and leukopenia. The bone marrow assessments showed dysplastic precursors including vacuolated myeloid and erythroid precursors and increased proportion of immature cells up to 19%. The patient received erythropoietin and G-CSF for myelodysplastic syndrome (MDS). No response was observed. During his evaluations copper deficiency was detected. One month after oral copper replacement, the peripheral blood counts and bone marrow findings became completely normalized. An evaluation to identify the cause of copper deficiency, revealed intestinal amyloidosis. Based on our experience we recommend serum copper determination in the diagnostic workup of MDS in patients with comorbidities.

Soluble platelet glycoprotein V in distinct disease states of pathological thrombopoiesis.

Quantitative platelet disorders (i.e., thrombocytosis or thrombocytopenia) may also be associated with qualitative platelet alterations. Clonal thrombocythemia (CT), reactive thrombocytosis (RT), immune thrombocytopenic purpura (ITP), and thrombocytopenia of aplastic pancytopenia (AA) or infiltrative bone marrow disorders represent the major classes of pathological thrombopoiesis. Glycoprotein V may serve as an in vivo marker of platelet activation in thrombotic and hemorrhagic states. The aim of this study was to assess circulating plasma soluble platelet glycoprotein V (sGPV) concentrations in distinct disease states of pathological thrombopoiesis. The whole study group comprised 20 patients with thrombocytopenia, 32 patients with thrombocytosis and 14 healthy adults as the control group. sGPV was significantly increased in the group of thrombocytosis patients in comparison to the thrombocytopenic group and the healthy control groups. When sGPV levels were corrected according to platelet number (sGPV/tr), this ratio was very high in patients with thrombocytopenia compared to patients with thrombocytosis and the control group. Our results suggest that there is an ongoing platelet activation associated with thrombocytosis regardless of its origin is either CT or RT. Therefore, glycoprotein V system may serve to activate residual platelets in thrombocytopenia regardless of its origin is either ITP or AA.

Efficiency of platelet-rich plasma on acellular dermal matrix application with coronally advanced flap in the treatment of multiple adjacent gingival recessions: A randomized controlled clinical trial.

BACKGROUND/PURPOSE: The aim of this study was to evaluate the effectiveness of platelet rich plasma (PRP) combined with coronally advanced flap plus acellular dermal matrix application (CAF + ADM) in the treatment of multiple adjacent gingival recessions (MAGRs). MATERIALS AND METHODS: 12 patients with 84 Miller Class I or II recession defects were participated. Sites were randomly assigned into CAF + ADM + PRP or CAF + ADM groups. Gingival recession depth (GRD), recession width (GRW), width of keratinized tissue (WKT), creeping attachment (CRA), root coverage (RC) as well as plaque index (PI), gingival index (GI), probing depth (PD), and clinical attachment level (CAL) were recorded at baseline and 3rd,6th and 12th months postoperatively. The data were analyzed statistically. RESULTS: GRD and GRW values were statistically higher in group CAF + ADM compared to the CAF + ADM + PRP group at 6th and 12th month (P < 0.05). CRA showed statistically significant increases in 3rd, 6th and 12th months with regard to the baseline in CAF + ADM + PRP group (P < 0.05), however CRA remained stable in CAF + ADM group at 6th and 12th month. The mean RC% was 77.9% and 69.4% for the CAF + ADM + PRP and CAF + ADM groups, respectively, at 12th month (P < 0.05). GRD reduction was statistically greater in the maxillary teeth treated with CAF + ADM + PRP compared to mandibular teeth treated with CAF + ADM at 12 months. CONCLUSION: Our data suggested that addition of PRP to CAF + ADM in the treatment of MAGRs significantly improved the clinical outcomes, according to 1-year follow-up results.(Clinicaltrials.gov identification NCT03043638).

Effects of Laser Photobiomodulation and Ozone Therapy on Palatal Epithelial Wound Healing and Patient Morbidity.

OBJECTIVE: The aim of this study was to compare the effects of laser photobiomodulation (PBM) and topical ozone therapy on the reepithelialization of palatal donor site wounds through clinical assessment and computer-aided image analysis and to assess the patient morbidity following free gingival graft (FGG) surgeries. MATERIAL AND METHODS: Thirty-six patients requiring FGG were randomly allocated into three groups: laser group (n = 12), ozone group (n = 12), and control group (n = 12). Epithelialization was evaluated by applying 3% hydrogen peroxide (H2O2) to the wound area and also measured by using digital image analysis (ImageJ). Bland-Altman plots were used for assessing agreement between H2O2 and ImageJ measurements. Parameters in relation to patient morbidity were assessed by using visual analog scale (VAS) on the first 3, 7, 14, and 30 days postoperatively. RESULTS: At day 14, statistically significant smaller wounds were observed with digital image analysis in the ozone group as compared with the control group (p = 0.034). However, intergroup comparison of the remaining wound area evaluated by the clinician using the H2O2 method did not reveal any significant differences (p > 0.05). Nonetheless, according to Bland-Altman analysis, the lower and upper limits showed a moderate agreement between the two measurement methods. The mean VAS sores exhibiting postoperative discomfort was observed to be significantly higher in the control group compared with the laser group (p = 0.002) and ozone group (p < 0.001) at day 7. CONCLUSIONS: Adjunctive ozone therapy could have a significantly beneficial effect on the acceleration of palatal wound healing following FGG procedures. Both PBM and ozone treatment modalities reduced postoperative discomfort as compared with spontaneous healing.

Unchanged global fibrinolytic capacity during the course of hematopoietic stem cell transplantation.

Hemostatic changes due to vascular endothelial damage are seen during the course of hematopoietic stem cell transplantation (HSCT). The fibrinolytic response to ongoing hemostatic activation in HSCT remains to be elucidated. Global fibrinolytic capacity (GFC) is a novel method, which reflects the amount of generated D-dimer when fibrinolysis of a freeze-dried fibrin clot is stopped by introducing aprotinin. GFC is sensitive to all the factors involved in the process of fibrinolysis. The aim of this study was to serially assess GFC at certain critical time points (days -1, +7, +14, +21 prior to and following stem cell infusion) during the course of HSCT. The study group comprised 16 patients with hematological malignancies (11 women, five men; median age 32+/-9 years) in whom HSCT had been performed. Thirty healthy adults (21 women, nine men; median age 31+/-7 years) served as controls. In this study, global fibrinolytic response, as reflected by GFC, was unchanged despite ongoing hemostatic activation, as indicated by D-dimer, moreover GFC remained stable, despite the development of thrombocytopenia associated with HSCT prior to platelet engraftment. Our results indicate that a global fibrinolytic response was impaired as a compensatory response to endothelial activation and to other hemostatic changes seen in HSCT. Further studies in larger HSCT populations are warranted to better understand the implications of these findings.

Expanded mesh connective tissue graft for the treatment of multiple gingival recessions.

BACKGROUND: The connective tissue graft procedure is an effective method to achieve root coverage. Although multiple sites often need grafting, the palatal mucosa supplies only a limited area of grafting material. The expanded mesh graft provides a method whereby a graft can be stretched to cover a larger area. The aim of this study was to determine the effectiveness and the predictability of expanded mesh connective tissue graft (e-MCTG) in the treatment of multiple gingival recessions. METHODS: Fifty-two buccal gingival recessions were treated in 10 systemically healthy patients. Fifteen recession treated operation sites with at least three adjacent Miller Class I and/or II recessions were performed. The connective tissue graft obtained from the palatal mucosa was expanded to cover the recipient bed, which was 1.5 times larger than the graft. Clinical measurements recorded at baseline and 12 months postoperatively included gingival recession depth (RD), gingival recession width (RW), percentage root coverage (RC), probing depth (PD), width of keratinized tissue (KT), and clinical attachment level (CAL). RESULTS: Twelve months after surgery, a statistically significant gain in CAL (3.2 +/- 0.8 mm, P < 0.001) and increase in KT (1.2 +/- 0.4, P < 0.001) were assessed. In 80% of the treated sites, 100% RC was achieved (mean 96%). CONCLUSIONS: The results of this study demonstrated that the use of e-MCTG technique allowed the treatment of multiple adjacent recessions with adequate wound healing and highly predictable root coverage. This procedure can be applied favorably in treating multiple gingival recessions in one surgery.

Comparative clinical study of connective tissue graft and two types of bioabsorbable barriers in the treatment of localized gingival recessions.

BACKGROUND: Localized buccal recessions occur in more than 60% of individuals; therefore, there is a need for predictable root coverage techniques. The objective of the present study was to evaluate the clinical effectiveness of the guided tissue regeneration (GTR) procedure versus connective tissue graft (CTG) in the treatment of localized gingival recessions over a 12-month postoperative period. METHODS: Thirty bilateral matched pairs of localized buccal recessions in 22 patients were treated with CTG and GTR in this study. For the GTR procedure, two types of bioabsorbable barriers, polylactide/polyglycolide acid (PLGA) and solvent dehydrated duramater allograft (SDDA) membranes, were used and CTG was obtained from the palatal mucosa. The selected pairs of teeth were randomly assigned to one of three groups (10 pairs per group): group 1, PLGA (10 recessions) or CTG (10 recessions); group 2, SDDA (10 recessions) or CTG (10 recessions); or group 3, PLGA (10 recessions) or SDDA (10 recessions). Statistical analysis evaluated both intra- and intergroup measurements. The height of gingival recession (GR), width of keratinized tissue (KT), clinical attachment level (CAL), and probing depth (PD) were assessed at baseline and at 6, 9, and 12 months following surgery. RESULTS: The amount of root coverage was 74.3%, 69.6%, and 86.3% with PLGA, SDDA, and CTG, respectively. The gain in KT was significant in the CTG group (P<0.05). No significant differences were observed among the three groups with respect to PD and CAL. CONCLUSIONS: Results of this study indicate that all techniques led to an improvement of all clinical parameters except PD from baseline. However, CTG increased KT considerably compared to GTR. The final esthetic results were similar for the two membranes and connective tissue graft.

Effect of polylactide/glycolide (PLGA) membranes loaded with metronidazole on periodontal regeneration following guided tissue regeneration in dogs.

BACKGROUND: Bioabsorbable membranes have been successfully used for guided tissue regeneration (GTR) and local delivery systems because they are biocompatible and do not require second surgery for removal. Several studies have demonstrated that metronidazole, when applied topically, produced immediate effects on microbiological and clinical parameters, most notably a reduction in probing depth and loss of attachment. The purpose of this study was to evaluate the regenerative potential of a metronidazole-loaded biodegradable (polylactide/glycolide) (PLGA) GTR membrane in dogs. METHODS: Six male adult dogs with 36 created osseous defects were enrolled. Bilateral dehiscence type defects in 5 mm diameter were created at buccal aspect of the alveolar bone in maxillary premolar teeth. After full thickness flap elevation, exposed root surfaces were thoroughly planed. In the experimental sites, PLGA membranes with or without metronidazole were fitted and placed over the defects. On the control defects only root planing was performed. Gingival flaps were replaced slightly coronal to the cemento-enamel junction. Animals were sacrificed at 60 days. The histometric analysis was evaluated with the following parameters: defect height (DH), apical extension of junctional epithelium (AEJE), new cementum height (NCH), new bone height (NBH), and new gingival connective tissue height (NCTH). RESULTS: Postoperative clinical healing was similar in the 3 groups. There were no statistically significant differences between the 2 experimental groups in any parameters. Statistically significant differences were observed for AEJE, NCH, NBH, and NCTH in experimental groups when compared with the controls. Statistically significantly greater NCH, NBH, and NCTH were seen in the experimental groups than the controls and control defects showed longer AEJE than the experimental defects. CONCLUSIONS: These results suggest that PLGA membranes with and without metronidazole may have a beneficial effect on periodontal regeneration.

Subgingival microflora in Turkish patients with periodontitis.

BACKGROUND: No information exists on periodontitis-associated subgingival microbiota from Turkey. We determined the occurrence, interspecies relationships, and clonal characteristics for a group of periodontal bacteria in a Turkish study population. METHODS: Subgingival microbial samples were obtained from patients with localized (LAgP, N = 18) or generalized (GAgP, N = 17) types of aggressive periodontitis, generalized chronic periodontitis (GCP, N = 14), and non-periodontitis subjects (N = 20). Culture methods were used to recover 6 periodontal bacterial species and yeasts, and a polymerase chain reaction technique was used to detect Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis. Intraspecies characterization of A. actinomycetemcomitans was carried out by serotyping and genotyping. RESULTS: All species, except for Micromonas micros (formerly Peptostreptococcus micros) occurred more frequently (P < 0.05) in periodontitis than non-periodontitis subjects. Detection frequencies for Tannerella forsythensis (formerly Bacteroides forsythus) and Campylobacter rectus differed among the periodontitis subgroups; the lowest frequency occurred in LAgP. The mean proportions of A. actinomycetemcomitans, P. gingivalis, and C. rectus were higher (P < 0.008) in GAgP than in non-periodontitis subjects. Significant positive associations were seen between 7 of the 22 possible combinations (P < 0.05). A. actinomycetemcomitans serotype c (34%) and non-serotypeable isolates (34%) were the most common antigenic types among the 305 strains analyzed. Eleven arbitrarily primed (AP)-PCR genotypes were distinguished among 273 isolates from 29 subjects. Yeasts were found in 23% of the 69 subjects. CONCLUSIONS: The results on the Turkish study population were generally in line with earlier reports on the occurrence and interspecies relationships of certain bacteria in periodontitis. However, A. actinomycetemcomitans was not overrepresented in LAgP, and the serotype distribution resembled that reported from the East. The high frequency of non-serotypeable isolates suggests local characteristics of the species.

Evaluation of periodontal healing in class II furcation defects following guided tissue regeneration with two different types of polylactic acid membranes.

BACKGROUND: Guided tissue regeneration procedures provide predictable reconstruction of periodontal tissues in the treatment of furcation involvements in animals and humans. This study was to compare long-term effectiveness of two different types of polylactic acid (PLA) membranes on periodontal regeneration in surgically created class II furcation defects in dogs. METHODS: Full thickness mucoperiosteal flap was raised on the buccal aspects of the experimental teeth and class II furcation defects having 5 mm vertical dimensions were created on mandibular premolar III and IV on each quadrant. The exposed root surfaces were thoroughly planed and PLA membranes were placed over the experimental defects on both sites. One site received liquid polymer membrane (LPM), and resorbable periodontal mesh (RPM) membranes were applied to the other site. The animals were sacrificed at 7 months after surgery and the specimens were processed for histological evaluation. RESULTS: The average length of new attachment formed on the treated roots in both groups ranged from 3.02 mm to 4.5 mm. Complete bone filling was observed at the furcation sites. No statistically significant differences were found between two membranes in any of the parameters (P > 0.05). CONCLUSION: This study demonstrates favorable regenerative outcomes by the use of two different types of PLA membranes that could be used as alternatives for guided tissue regeneration (GTR).