DETECTION OF MOGIBACTERIUM TIMIDUM IN SUBGINGIVAL BIOFILM OF AGGRESSIVE AND NONDIABETIC AND DIABETIC CHRONIC PERIODONTITIS PATIENTS

The aim of the present study was to evaluate the frequency of detection of Mogibacterium timidum in subgingival samples of subjects with generalized aggressive periodontitis (GAgP) and uncontrolled diabetic and non-diabetic subjects with generalized chronic periodontitis (GChP). 48 patients with GAgP, 50 nondiabetic and 39 uncontrolled (glycated hemoglobin >7%) type 2 diabetic subjects with GChP were enrolled in this study. Subgingival biofilm were collected from deep pockets (probing depth > 7 mm). After DNA extraction, M. timidum was detected by Nested Polymerase Chain Reaction and chi-square test was used to data analysis (p>0.05). There were no differences in the frequency of detection of M. timidum between subjects with GAgP (35%) and non-diabetic subjects with GChP (40%) (p>0.05). The frequency of detection of M. timidum was significantly higher in deep pockets of diabetic subjects with GChP (56%) when compared to GAgP (p0.05). The frequency of detection of M. timidum was higher in subjects GChP presenting uncontrolled type 2 diabetes mellitus, when compared to GAgP subjects.43393193

Protective effect of topical Cordia verbenacea in a rat periodontitis model: immune-inflammatory, antibacterial and morphometric assays

Background: This study evaluated the effects of C. verbenacea essential oil topically administered in a rat periodontitis model. Methods: Periodontitis was induced on rats in one of the mandibular first molars assigned to receive a ligature. Animals were randomly divided into two groups: a) non-treatment group (NT) (n = 18): animals received 1mL of vehicle; b) C. verbenacea group (C. v.) (n = 18): animals received 5mg/Kg of essential oils isolated from C. verbenacea. The therapies were administered topically 3 times daily for 11 days. Then, the specimens were processed for morphometric analysis of bone loss. The ligatures were used for microbiological assessment of the presence of Aggregatibacter actinomycetemcomitans, Tannerella forsythia and Porphyromonas gingivalis using PCR. The gingival tissue was collected to Elisa assay of interleukin (IL)-1 alpha and IL-10 levels. Results: Bone loss was inhibited by C. verbenacea when compared to the NT group (p < 0.05). A decrease in the levels of IL-1 alpha and increase in the IL-10 amounts was observed in the C. v. group as compared to NT group (p < 0.05). A lower frequency of P. gingivalis was found in C. v. group (p < 0.05). Conclusion: C. verbenacea essential oil topically administered diminished alveolar bone resorption, promoting a positive local imbalance in the pro/anti-inflammatory system and reducing the frequency of detection of P. gingivalis.1

Development of an in vitro periodontal biofilm model for assessing antimicrobial and host modulatory effects of bioactive molecules

Background: Inflammation within the oral cavity occurs due to dysregulation between microbial biofilms and the host response. Understanding how different oral hygiene products influence inflammatory properties is important for the development of new products. Therefore, creation of a robust host-pathogen biofilm platform capable of evaluating novel oral healthcare compounds is an attractive option. We therefore devised a multi-species biofilm co-culture model to evaluate the naturally derived polyphenol resveratrol (RSV) and gold standard chlorhexidine (CHX) with respect to anti-biofilm and anti-inflammatory properties.&lt;p&gt;&lt;/p&gt; Methods: An in vitro multi-species biofilm containing &lt;i&gt;S. mitis, F. nucleatum, P. Gingivalis&lt;/i&gt; and &lt;i&gt;A. Actinomycetemcomitans&lt;/i&gt; was created to represent a disease-associated biofilm and the oral epithelial cell in OKF6-TERT2. Cytotoxicity studies were performed using RSV and CHX. Multi-species biofilms were either treated with either molecule, or alternatively epithelial cells were treated with these prior to biofilm co-culture. Biofilm composition was evaluated and inflammatory responses quantified at a transcriptional and protein level.&lt;p&gt;&lt;/p&gt; Results: CHX was toxic to epithelial cells and multi-species biofilms at concentrations ranging from 0.01-0.2%. RSV did not effect multi-species biofilm composition, but was toxic to epithelial cells at concentrations greater than 0.01%. In co-culture, CHX-treated biofilms resulted in down regulation of the inflammatory chemokine IL-8 at both mRNA and protein level. RSV-treated epithelial cells in co-culture were down-regulated in the release of IL-8 protein, but not mRNA.&lt;p&gt;&lt;/p&gt; Conclusions: CHX possesses potent bactericidal properties, which may impact downstream inflammatory mediators. RSV does not appear to have bactericidal properties against multi-species biofilms, however it did appear to supress epithelial cells from releasing inflammatory mediators. This study demonstrates the potential to understand the mechanisms by which different oral hygiene products may influence gingival inflammation, thereby validating the use of a biofilm co-culture model.&lt;p&gt;&lt;/p&gt

Experimental Animal Models in Periodontology: A Review

In periodontal research, animal studies are complementary to in vitro experiments prior to testing new treatments. Animal models should make possible the validation of hypotheses and prove the safety and efficacy of new regenerating approaches using biomaterials, growth factors or stem cells. A review of the literature was carried out by using electronic databases (PubMed, ISI Web of Science). Numerous animal models in different species such as rats, hamsters, rabbits, ferrets, canines and primates have been used for modeling human periodontal diseases and treatments. However, both the anatomy and physiopathology of animals are different from those of humans, making difficult the evaluation of new therapies. Experimental models have been developed in order to reproduce major periodontal diseases (gingivitis, periodontitis), their pathogenesis and to investigate new surgical techniques. The aim of this review is to define the most pertinent animal models for periodontal research depending on the hypothesis and expected results

Effect of Aluminum Oxide-Blasted Implant Surface on the Bone Healing Around Implants in Rats Submitted to Continuous Administration of Selective Cyclooxygenase-2 Inhibitors

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Purpose: The continual use of selective cyclooxygenase-2 (COX-2) inhibitors may have a negative impact on bone repair around titanium implants. Because modified implant surfaces could be considered an important strategy to increase success rates in some conditions that interfere in bone healing, the aim of this study was to investigate whether an aluminum oxide (Al(2)O(3))-blasted implant surface could reduce the negative action promoted by the continuous administration of selective COX-2 inhibitors on bone healing around implants. Materials and Methods: Thirty Wistar rats received one titanium implant (machined or Al(2)O(3)-blasted surface) in each tibia and were randomly assigned to one of the following groups: saline (n = 14) or meloxicam (n = 16); each was administered daily for 60 days. Bone-to-implant contact (BIC), bone area (BA) within the limits of threads, and bone density (BD) in a zone lateral to the implant were examined in undecalcified sections. Results: The Al(2)O(3)-blasted surface resulted in significantly increased BIC in both groups, and meloxicam significantly reduced bone healing around implants (P < .05). For the machined surface, significant differences were observed for BIC (39.48 +/- 10.18; 25.23 +/- 9.29), BA (60.62 +/- 4.09; 42.94 +/- 8.12), and BD (56.31 +/- 3.64; 49.30 +/- 3.15) in the saline and meloxicam groups, respectively. For the Al(2)O(3)-blasted surface, data analysis also demonstrated significant differences for BIC (45.92 +/- 11.34; 33.30 +/- 7.56), BA (61.04 +/- 4.39; 44.89 +/- 7.11), and BD (58.77 +/- 2.93; 50.04 +/- 3.94) for the saline and meloxicam groups, respectively. Conclusions: The Al(2)O(3)-blasted surface may increase BIC, however, it does not reverse the negative effects promoted by a selective COX-2 inhibitor on bone healing around implants. Int J Oral Maxillofac Implants 2009; 24:226-233242226233Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP [04/15825-6, 04/12430-(0)

A randomized clinical evaluation of triclosan-containing dentifrice and mouthwash association in the control of plaque and gingivitis

Objective: The aim of this double-blind study was to evaluate the clinical efficacy of the association of triclosan-containing mouthrinse and dentifrice on biofilm and gingivitis reduction. Method and Materials: Forty patients with a diagnosis of gingivitis were selected and randomly divided into four groups (n = 10): group TT-triclosan-containing mouthrinse and triclosan-containing dentifrice; group CT-control mouthrinse and triclosan-containing dentifrice; group TC-triclosan-containing mouthrinse and control dentifrice; group CC-control mouthrinse and control dentifrice. Patients were evaluated by a calibrated examiner using a quantitative Plaque Index and Gingivitis Index at 0, 15, and 30 days. Intragroup analysis was performed by Friedman test and intergroup analysis by Kruskal-Wallis. Results: Intragroup evaluation revealed a statistically significant reduction in Plaque Index for groups that used triclosan, independently of the group (TT, CT, and TC) (P < .05). Intergroup analysis suggested that only the group that used the association of triclosan dentifrice and mouthrinse (group TT) demonstrated statistically reduced Plaque Index at 30 days, when compared to the control group (CC) (P < .05). With regard to gingivitis reduction, no difference was observed between groups, although the association presented a faster reduction in bleeding levels. Conclusion: Only the association of triclosan dentifrice and triclosan mouthrinse statistically reduced Plaque Index, when compared to the control group; however, regarding the additional benefits to gingivitis control, more studies should be done to confirm the results. (Quintessence Int 2010; 41: 855-861)411085586

Inflammatory and bone-related genes are modulated by aging in human periodontal ligament cells

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Periodontal ligament cells (PDLC) play a major role in periodontal tissues homeostasis and destruction. Most age-associated diseases seem to be closely related to an underlying chronic inflammatory state. Thus, the present study aimed at evaluating in PDLC the effect of aging on the basal levels of inflammatory and bone-related genes. Primary PDLC cultures were obtained from subjects aged 15-20 years (control- n = 5), and subjects aged more than 60 years (test- n = 5). Proliferation, cell viability and total secreted protein assays were performed, and mRNA levels were quantitatively assessed for interleukin (IL)-I beta, IL-4, IL-6 and IL-8, and for receptor activator of nuclear factor-kappa B ligand (RANKL) and osteoprotegerin (OPG) by real time PCR. Data analysis demonstrated that aging negatively influenced cell proliferation, whereas cell viability and total secreted protein were not affected (p > 0.05). Gene expression analysis showed that mRNA levels for RANKL and IL-8 were not affected by aging (p > 0.05) whereas, mRNA levels for IL-4 was significantly lower in aged cells (p < 0.05) and OPG, IL-1 beta and IL-6 mRNA levels were higher (p < 0.05). Data analysis suggests that aging decreased the ability of PDLC to proliferate and modulated the expression of important inflammatory and bone-related genes in periodontal ligament cells, favoring a proinflammatory and an antiresorptive profile. (C) 2009 Elsevier Ltd. All rights reserved.462176181Sao Paulo State FoundationConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Surgical Microscope May Enhance Root Coverage With Subepithelial Connective Tissue Graft: A Randomized-Controlled Clinical Trial

Background: Minimally invasive techniques have broadened the horizons of periodontal plastic surgery to improve treatment outcomes. Thus, the purpose of this clinical trial was to compare root coverage, postoperative morbidity, and esthetic outcomes of subepithelial connective tissue graft (SCTG) technique with or without the use of a surgical microscope in the treatment of gingival recessions. Methods: In this split-mouth study, twenty-four patients with bilateral Miller's Class I or II buccal gingival recessions >= 2.0 mm in canines or premolars were selected. Gingival recessions were randomly designated to receive treatment with SCTG with or without the assistance of the surgical microscope (test and control groups, respectively). Clinical parameters evaluated included the following: depth (RH) and width (RW) of the gingival defect, width (WKT) and thickness (TKT) of keratinized tissue, probing depth (PD), and clinical attachment level (CAL). Postoperative morbidity was evaluated by means of an analog visual scale and questionnaire. Patient satisfaction was also evaluated with a questionnaire. Descriptive statistics were expressed as mean +/- SD. Repeated-measures analysis of variance was used for examination of differences regarding PD, CAL, and TKT. The Wilcoxon test was used to detect differences between groups and the Friedman test to detect differences within group regarding WKT, RH, and RW. Results: The average percentages of root coverage for test and control treatments, after 12 months, were 98.0% and 88.3%, respectively (P<0.05). Complete root coverage was achieved in 87.5% and 58.3% of teeth treated in test and control groups, respectively. For all parameters except recession height, there was an improvement in the final examination but without difference between treatments. For the RH, a lower value was found in the test group compared to the control group (P<0.05). In the test group, all patients were satisfied with the esthetics obtained, and 19 patients (79.1%) were satisfied in the control group. For postoperative morbidity, 14 patients in each of the two treatment groups did not use analgesics for pain control. Conclusion: Both approaches were capable of producing root coverage; however, use of the surgical microscope was associated with additional clinical benefits in the treatment of teeth with gingival recessions. J Periodontol 2012;83:721-730.836721730Research Funding Agency of Bahia State, Brazil [2409/2005]Research Funding Agency of Bahia State, Brazil [2409/2005

Smoking may affect the alveolar process dimensions and radiographic bone density in maxillary extraction sites: A prospective study in humans

Purpose: Loss of ridge width and height typically occur after tooth extraction. This study aimed to investigate whether smoking would effect alveolar ridge remodeling after tooth extraction. Materials and Methods: Twenty-one individuals (11 nonsmokers, 10 smokers) requiring a nonmolar extraction in the tipper jaw were selected. Radiographs were taken 7 and 180 days after surgery, and the following parameters obtained: alveolar process height (AH), alveolar process width (AW), radiographic bone density in the postextraction socket (BDS), and in the pre-existing bone apically (BDPB). Results: Six months after surgery, intragroup, analysis showed that both groups presented a significant reduction in AH, while only smokers had a significant reduction in AW, BDS, and BDPB (P < .05). Furthermore, intergroup analysis showed that smokers presented lower BDS (91.45 pixels +/- 26.62 and 59.53 pixels +/- 19.99, for nonsmokers and smokers, respectively; P = .006) and continued to present lower BDPB (129-34 pixels +/- 42.10 and 89.29 pixels +/- 29.96, for nonsmokers and smokers, respectively; P = .023). Additionally, smokers presented a tendency for lower AH and AW than nonsmokers, but this was not statistically significant. Conclusion: Within the limits of the present study, smoking may lead to a more significant dimensional reduction of the residual alveolar ridge and postpone postextraction socket heating. (c) 2006 American Association of Oral and Maxillofacial Surgeons.6491359136

Enamel matrix derivative and bone healing after guided bone regeneration in dehiscence-type defects around implants. A histomorphometric study in dogs

Background: The goal of this investigation was to histometrically evaluate the effect of enamel matrix derivative (EMD) on bone healing after guided bone regeneration (GBR) in dehiscence-type osseous defects around dental implants; i.e., in the absence of periodontal ligament cells. Methods: Six mongrel dogs were used. The second, third, and fourth mandibular premolars (p2, p3, and p4) and first molars (ml) were extracted. After 3 months, 2 implant osteotomies were prepared in each side of the mandible, dehiscence-type defects were created on the buccal aspect of each implant osteotomy (3.5 mm x 5.0 mm), and titanium implants were placed (3.75 mm x 8.5 mm). The surgically-created defects were randomly assigned to one of the treatments: EMD, GBR, EMD+GBR, or control. After 2 months, 4 additional defects were created and treated. The animals were sacrificed 3 months after the placement of the first implants, thus allowing the healing periods of 1 and 3 months. Undecalcified sections were obtained for the histometric evaluation including the percentage of bone-to-implant contact and new bone area on the implant threads related to the defect. Results: No statistically significant differences were observed among the groups in the evaluated parameters after 1 month of healing. After 3 months, no statistically significant differences were observed among the groups for the percentage of bone-to-implant contact. The values for the new bone area were: 55.5 +/- 11.8, 53.8 +/- 16.3, 62.1 +/- 18.4, and 36.9 +/- 25.1 for EMD, GBR, EMD+GBR, and control, respectively. The difference between EMD+GBR and control was statistically significant (P <0.05). Conclusions: Within the limits of this study, it can be concluded that EMD may positively influence bone healing after GBR around titanium implants. EMD alone, however, had no statistically significant effect.73778979