Supportive periodontal care with or without subgingival instrumentation: Microbiological results of a 2-year randomized clinical trial.

AIM: To compare the subgingival microbiota of patients receiving supportive periodontal care (SPC) with and without subgingival instrumentation, over 2 years. MATERIALS AND METHODS: This study was a randomized clinical trial that included 62 participants (50.97 ± 9.26 years old; 40 females) who completed non-surgical periodontal therapy. Participants were randomly assigned to receive oral prophylaxis with oral hygiene instructions alone (test) or in combination with subgingival instrumentation (control) during SPC. Pooled subgingival biofilm samples were obtained from four sites per patient at SPC baseline and at 3, 6, 12, 18, and 24 months. Real-time polymerase chain reaction was used for absolute quantification of Eubacteria and the target bacteria Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola. Data were analysed using generalized estimating equations, taking into consideration the clustering of observations within individuals. RESULTS: No significant differences were found between the experimental groups regarding the mean counts of Eubacteria and target bacteria, as well as the periodontal parameters at the sampled sites. Although significant variability in bacterial counts was present during SPC, all counts after 2 years were not statistically different from those at baseline. Bacterial counts were associated with the presence of plaque, bleeding on probing, mean probing depth ≥3 mm, and follow-up period. CONCLUSIONS: SPC with or without subgingival instrumentation can result in comparable subgingival microbiological outcomes. CLINICAL TRIAL REGISTRATION: clinicaltrials.gov: NCT01598155 (https://clinicaltrials.gov/study/NCT01598155?intr=supragingival%20control&rank=4#study-record-dates).

Dental erosion among South Brazilian adolescents: A 2.5-year longitudinal study.

OBJECTIVES: This population-based longitudinal study investigated the incidence, progression and risk factors for dental erosion among South Brazilian adolescents. METHODS: Eight hundred and one schoolchildren attending 42 public and private schools were clinically examined at 12 years of age; clinical examinations were repeated after 2.5 years (SD=0.3). After tooth cleaning and drying, permanent incisors and first molars were classified using the Basic Erosive Wear Examination (BEWE) scoring criteria. Questionnaires were used to collect data on socio-demographic characteristics, dietary habits, toothbrushing frequency and general health. Poisson regression analysis was used to assess the association between dental erosion incidence and explanatory variables, with adjusted incidence risk ratios (IRR) and 95% CI estimated. RESULTS: Among those who did not have dental erosion at baseline, 49 of 680 schoolchildren (7.1%; 95% CI=5.2-9.1) developed erosive lesions over the follow-up period. Among schoolchildren who had dental erosion at baseline, 31 of 121 (25.4%; 95% CI=17.6-33.3) had new or more severe lesions. Boys were more likely to develop dental erosion than girls (IRR=1.88; 95% CI=1.06-3.32). CONCLUSIONS: A moderate incidence of dental erosion was observed among South Brazilian adolescents, with boys being at higher risk. The high progression rate of 25% observed here is very concerning, and it should be taken in consideration when designing preventive strategies for dental erosion.

Comparative effectiveness of water and salt community-based fluoridation methods in preventing dental caries among schoolchildren.

OBJECTIVE: To compare the effectiveness of water and salt community-based fluoridation methods on caries experience among schoolchildren. METHODS: Data derived from two population-based oral health surveys of 12-year-old schoolchildren exposed to different community-based fluoridation methods were compared: artificially fluoridated water in Porto Alegre, South Brazil and artificially fluoridated salt in Montevideo, Uruguay. Data on socio-demographic characteristics, maternal education and oral hygiene were collected. Dental caries was defined according to the WHO criteria (cavitated lesions) and to the modified WHO criteria (active noncavitated lesions and cavitated ones). The association between community-based fluoridation methods and dental caries was modelled using logistic (caries prevalence) and Poisson regression (DMFT). Odds ratios (OR), rate ratios (RR), and the 95% confidence intervals (CI) were estimated. RESULTS: A total of 1528 in Porto Alegre and 1154 in Montevideo were examined (response rates: 83.2% and 69.6%, respectively). Adjusted estimates for caries prevalence and DMFT showed that schoolchildren from Porto Alegre were less affected by dental caries than their counterparts from Montevideo, irrespective of the criteria used. After adjusting for important characteristics, schoolchildren exposed to fluoridated salt had significantly higher likelihood of having caries (WHO criteria) than those exposed to fluoridated water (OR for prevalence=1.61, 95% CI=1.26-2.07; RR for DMFT=1.32, 95% CI=1.16-1.51). Similar differences were observed using the modified WHO criteria. CONCLUSION: Fluoridated water appears to provide a better protective effect against dental caries than fluoridated household salt among schoolchildren from developing countries.

The association between alcohol consumption and periodontitis in southern Brazilian adults.

BACKGROUND AND OBJECTIVE: An association between alcohol consumption and periodontitis has been suggested in the literature, but the evidence is still unclear. The aim of the present study was to investigate the relationship between alcohol consumption and periodontitis in a probability sample of adults from south Brazil. MATERIAL AND METHODS: This analysis included 1115 subjects aged 18-65 years derived from a representative sample from south Brazil. Data were collected from participants from clinical examination and structured interviews. Alcohol consumption was assessed by asking participants about the usual number of drinks consumed in a week. Four categories of alcohol consumption were defined: non-drinker, ≤ 1 glass/wk, > 1 glass/wk, ≤ 1 glass/d and > 1 glass/d. Individuals with ≥ 30% teeth with periodontal attachment loss ≥ 5 mm were classified as having periodontitis. Logistic models adjusting for age, race, socioeconomic status, dental care, body mass index, self-reported diabetes and smoking were used to estimate odds ratios (OR) and confidence intervals (95% CI). RESULTS: After adjusting for co-factors, females who reported drinking > 1 glass/d were more likely to have periodontitis (OR = 3.8, 95% CI = 1.4-10.1), whereas females who reported drinking up to 1 glass/d were 50% less likely to have periodontitis (OR = 0.5, 95% CI = 0.3-0.8). No significant associations between overall alcohol intake and periodontitis were observed for males. In an exploratory analysis, wine consumption was associated with a lower likelihood of periodontitis among males (OR = 0.2, 95% CI = 0.1-0.5) but not females. CONCLUSION: The periodontal health of males and females appears to be affected differently by alcohol consumption. Moderate wine consumption may have a beneficial effect in males.

Eruption stage of permanent molars and occlusal caries activity/arrest.

This study assessed the association between the eruption stage of permanent second molars and occlusal caries activity among 12-year-old schoolchildren from South Brazil. A cross-sectional study was performed in Porto Alegre using a multistage probability sampling strategy to select a representative sample. Clinical examination was conducted to assess the eruption stage of permanent molars, Gingival Bleeding Index, and, after tooth cleaning and drying, caries experience (noncavitated and cavitated lesions, including caries activity assessment). Data were collected on sex, socioeconomic status, mother's education, brushing frequency, and consumption of soft drinks. Generalized estimating equations were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Overall, 983 schoolchildren with 3,071 second molars were available for analysis. Whereas active caries was observed in 6.6% of fully erupted permanent second molars, caries affected 26.2%, 29.6%, and 18.2% of erupting molars classified as stages 1, 2, and 3, respectively: stage 1, partially erupted occlusal surface; stage 2, fully erupted occlusal surface, <1/2 crown exposed; and stage 3, fully erupted occlusal surface, >1/2 crown exposed. After adjusting for socioeconomic and behavioral variables, partially erupted molars were significantly more likely to present active caries lesions than molars in full occlusion: stage 1, OR = 4.99 (95% CI = 3.38, 7.38); stage 2, OR = 5.18 (95% CI = 3.14, 8.53); stage 3, OR = 3.20 (95% CI = 2.21, 4.64). Similar results were found when clinical variables were included in the adjusted model. In conclusion, most occlusal caries lesions tend to arrest/revert when teeth reach the occlusal plan; however, an important proportion of these lesions remains active and in need of proper management. Children at risk should be targeted with preventive and minimally invasive strategies.

Tooth loss prevalence and risk indicators among 12-year-old schoolchildren from South Brazil.

This population-based cross-sectional study aimed to assess the prevalence and risk indicators for tooth loss due to dental caries among 12-year-old schoolchildren from South Brazil. 1,528 out of 1,837 (participation rate = 83.17%) schoolchildren were included. Tooth loss prevalence was 5.81% (95% CI = 3.71-8.98) and 0.08 (95% CI = 0.04-0.12) teeth were missing. Schoolchildren with low socioeconomic status (OR = 2.28, 95% CI = 1.23-4.21), who repeated years in school (OR = 1.56, 95% CI = 1.01-2.42), and with gingivitis (OR = 1.81, 95% CI = 1.33-2.45) were more likely to have missing teeth. Schoolchildren brushing 2 times/day (OR = 0.78, 95% CI = 0.64-0.96) or more (OR = 0.49, 95% CI = 0.33-0.74), and those with dental insurance or private dentists (OR = 0.60, 95% CI = 0.39-0.93) were less likely to present missing teeth. © 2014 S. Karger AG, Basel.

Glycogen synthase kinase-3 inhibitors as potent therapeutic agents for the treatment of Parkinson disease.

Parkinson's disease (PD) is a devastating neurodegenerative disorder characterized by degeneration of the nigrostriatal dopaminergic pathway. Because the current therapies only lead to temporary, limited improvement and have severe side effects, new approaches to treat PD need to be developed. To discover new targets for potential therapeutic intervention, a chemical genetic approach involving the use of small molecules as pharmacological tools has been implemented. First, a screening of an in-house chemical library on a well-established cellular model of PD was done followed by a detailed pharmacological analysis of the hits. Here, we report the results found for the small heterocyclic derivative called SC001, which after different enzymatic assays was revealed to be a new glycogen synthase kinase-3 (GSK-3) inhibitor with IC(50) = 3.38 ± 0.08 µM. To confirm that GSK-3 could be a good target for PD, the evaluation of a set of structurally diverse GSK-3 inhibitors as neuroprotective agents for PD was performed. Results show that inhibitors of GSK-3 have neuroprotective effects in vitro representing a new pharmacological option for the disease-modifying treatment of PD. Furthermore, we show that SC001 is able to cross the blood-brain barrier, protects dopaminergic neurons, and reduces microglia activation in in vivo models of Parkinson disease, being a good candidate for further drug development.

Effect of bone morphogenetic protein-2, demineralized bone matrix and systemic parathyroid hormone (1-34) on local bone formation in a rat calvaria critical-size defect model.

AIM: To determine the potential of recombinant human bone morphogenetic protein-2 (rhBMP-2) soak-loaded on to an absorbable collagen sponge (ACS) to induce local bone formation compared with the clinical reference demineralized bone matrix (DBM) and to investigate potential additive/synergistic effects of exogenous parathyroid hormone (PTH). METHODS: Critical-size (8 mm), through-through calvaria osteotomy defects in 160 adult male Sprague-Dawley rats were randomized to receive one of eight interventions: rhBMP-2/ACS, DBM, ACS, or serve as controls (empty defects) combined or not with systemic PTH. Ten animals from each group were followed for 4 and 8 wks for radiographic and histometric analysis. Multivariable analysis was used to assess the effect of experimental intervention and healing time on local bone formation. RESULTS: In the multivariable analysis, rhBMP-2/ACS exhibited significantly greater histologic bone formation than control (ß ± SE: 54.76 ± 5.85, p < 0.001) and ACS (ß ± SE: 9.14 ± 3.31, p = 0.007) whereas DBM showed significantly less bone formation than control (ß ± SE: -32.32 ± 8.23, p < 0.001). Overall, PTH did not show a significant effect on bone formation (ß ± SE: 2.72 ± 6.91, p = 0.70). No significant differences in histological defect closure were observed between 4 and 8 wks for all but the control group without PTH. CONCLUSION: rhBMP-2/ACS significantly stimulates local bone formation whereas bone formation appears significantly limited by DBM. Systemic application of PTH provided no discernible additive/synergistic effects on local bone formation.

Effect of nonsurgical periodontal therapy on serum and gingival crevicular fluid cytokine levels during pregnancy and postpartum.

BACKGROUND AND OBJECTIVE: A low-grade systemic inflammatory status originating from periodontal infection has been proposed to explain the association between periodontal disease and systemic conditions, including adverse obstetric outcomes. The aim of this study was to evaluate the effect of periodontal therapy during pregnancy on the gingival crevicular fluid and serum levels of six cytokines associated with periodontal disease and preterm birth. MATERIAL AND METHODS: A subsample of 60 women (18-35 years of age) up to 20 gestational weeks, previously enrolled in a larger randomized clinical trial, was recruited for the present study. Participants were randomly allocated to receive either comprehensive nonsurgical periodontal therapy before 24 gestational weeks (n = 30, test group) or only one appointment for supragingival calculus removal (n = 30, control group). Clinical data, and samples of blood and gingival crevicular fluid, were collected at baseline, at 26-28 gestational weeks and 30 d after delivery. The levels of interleukin (IL)-1ß, IL-6, IL-8, IL-10, IL-12p70 and tumor necrosis factor-α were analyzed by flow cytometry. RESULTS: After treatment, a major reduction in periodontal inflammation was observed in the test group, with bleeding on probing decreasing from 49.62% of sites to 11.66% of sites (p < 0.001). Periodontal therapy significantly reduced the levels of IL-1ß and IL-8 in gingival crevicular fluid (p < 0.001). However, no significant effect of therapy was observed on serum cytokine levels. After delivery, the levels of IL-1ß in the gingival crevicular fluid of the test group were significantly lower than were those in the control group (p < 0.001), but there were no significant differences between test and control groups regarding serum cytokine levels. CONCLUSION: Although periodontal therapy during pregnancy successfully reduced periodontal inflammation and gingival crevicular fluid cytokine levels, it did not have a significant impact on serum biomarkers.

Exploratory study on the effect of osteoactivin on bone formation in the rat critical-size calvarial defect model.

BACKGROUND AND OBJECTIVE: Osteoactivin is a novel glycoprotein shown to exhibit an important role in regulating osteoblast differentiation and function. The aim of the present study was to evaluate the potential of osteoactivin to support bone regeneration using an established defect model. MATERIAL AND METHODS: Critical-size, 8-mm-diameter through-and-through calvarial osteotomy defects were created in 60 adult male Sprague-Dawley rats. Test animals received 0.1 mL of osteoactivin in phosphate-buffered saline (50 µg/mL) soak-loaded onto an absorbable collagen sponge. Controls received 0.1 mL of phosphate-buffered saline soak-loaded onto the absorbable collagen sponge or no further intervention (sham-surgery). The animals were euthanized 2 and 4 wk after treatment and histometric analyses were performed. RESULTS: The absorbable collagen sponge control (mean ± standard deviation: 40.9 ± 26.9%) showed borderline significant greater bone fill compared with sham-surgery (22.9 ± 15.8%; p = 0.10) and osteoactivin (20.2 ± 11.8%; p = 0.07) treatments at 2 wk. In contrast, osteoactivin (84.7 ± 15.8%) showed significantly greater bone fill than sham-surgery (28.4 ± 9.6%; p < 0.001) and absorbable collagen sponge (41.8 ± 22.1%; p < 0.001) at 4 wk. No animals receiving sham-surgery or absorbable collagen sponge exhibited complete bone fill at 4 wk while 70% of the animals receiving osteoactivin showed complete bone fill. CONCLUSION: Osteoactivin demonstrates a significant potential to support bone regeneration/formation. Studies using discriminating large animal models are necessary to explore clinical application for periodontal and craniofacial indications.

Prevalence and risk indicators of oral mucosal lesions in an urban population from South Brazil.

OBJECTIVE: The objective of the study was to assess the prevalence of oral mucosal lesions (OML) and to perform a multivariable risk assessment of demographic, socioeconomic, behavioral, and oral risk indicators for its occurrence in an urban population in South Brazil. METHODS: This cross-sectional study selected 1586 subjects (719M/867F, age: 14-104 years) using a multistage probability sampling strategy (65.1% response rate). Prevalence, odds ratios (OR), and confidence intervals (95% CI) were calculated accounting for the survey design. RESULTS: Leukoplakia and lichen planus were observed in 1.01% and 1.02% of subjects, respectively. In the multivariable analysis, these lesions were significantly associated with moderate/heavy smoking (OR = 9.0, 95% CI = 2.1-39.1) and heavy drinking (OR = 2.0, 95% CI = 1.1-3.7). Candidiasis and proliferative lesions were observed in 14.09% and 3.80% of the subjects, respectively. These lesions were significantly associated with female gender (OR = 2.2, 95% CI = 1.5-3.2 and OR = 1.7, 95% CI = 1.0-2.8), older age (OR=22, 95% CI = 8.0-60.8 and OR = 8.9, 95% CI = 3.4-23.7), and low socioeconomic status (OR = 1.9, 95% CI = 1.0-3.5 and OR = 3.0, 95% CI = 1.2-7.2). CONCLUSIONS: This population is in need of OML prevention and treatment. Future studies should validate the findings that premalignant lesions are causally related to smoking and alcohol consumption, and that other OML are associated with socioeconomic-demographic disparities in this and similar populations.

Bone morphogenetic proteins for periodontal and alveolar indications; biological observations - clinical implications.

Surgical placement of endosseous oral implants is governed by the prosthetic design and by the morphology and quality of the alveolar bone. Nevertheless, often implant placement may be complexed, if at all possible, by alveolar ridge irregularities resulting from periodontal disease, and chronic and acute trauma. In consequence, implant positioning commonly necessitates bone augmentation procedures. One objective of our laboratory is to evaluate the biologic potential of bone morphogenetic proteins (BMP) and other candidate biologics, bone biomaterials, and devices for alveolar ridge augmentation and implant fixation using discriminating large animal models. This focused review illustrates the unique biologic potential, the clinical relevance and perspectives of recombinant human BMP-2 (rhBMP-2) using a variety of carrier technologies to induce local bone formation and implant osseointegration for inlay and onlay indications. Our studies demonstrate a clinically relevant potential of a purpose-designed titanium porous oxide implant surface as stand-alone technology to deliver rhBMP-2 for alveolar augmentation. In perspective, merits and shortcomings of current treatment protocol including bone biomaterials and guided bone regeneration are addressed and explained. We demonstrate that rhBMP-2 has unparalleled potential to augment alveolar bone, and support implant osseointegration and long-term functional loading. Inclusion of rhBMP-2 for alveolar augmentation and osseointegration will not only enhance predictability of existing clinical protocol but also radically change current treatment paradigms.

Effect of age on gingival crevicular fluid concentrations of MIF and PGE2.

We used an experimental gingivitis study design to compare crevicular fluid concentrations of Migration Inhibitory Factor (MIF) and Prostaglandin E(2) (PGE(2)) in younger (18 to 30 yrs) and older (46 to 77 yrs) healthy adults. PGE(2) increased after 1 wk in younger participants, whereas it decreased in older individuals after 1 wk of plaque accumulation. A significant interaction between age and time was observed for PGE(2) (p = 0.04). High concentrations of MIF were identified in both age groups at baseline. MIF increased in the younger participants, whereas in the older individuals a decrease over time was observed. MIF concentration was positively correlated with plaque index and gingival index in the older age group. Total counts of bacteria, Parvimonas micra and Prevotella intermedia, were significantly correlated with MIF concentration in older participants. In conclusion, MIF and PGE(2) production in response to bacterial accumulation seems to be modified by age.

Quantitative detection of Clostridium difficile in hospital environmental samples by real-time polymerase chain reaction.

C. difficile-associated diarrhoea occurs commonly in hospitals and is a significant cause of morbidity and mortality. Hospital surfaces are often contaminated with nosocomial pathogens and may be responsible for cross-transmission, especially if hardy Gram-positive and spore-forming organisms are involved. The aim of this study was to quantify C. difficile in the hospital environment near C. difficile-positive and -negative patients using a quantitative real-time polymerase chain reaction. A total of 531 samples was collected from the clinical environment and classified into three groups according to patient and ward status for C. difficile. As expected, there were significantly higher counts of C. difficile on the floor and in the near environment of C. difficile patients. However, a significant correlation was found between C. difficile counts on the floor and on the hands of patients and healthcare workers (HCWs) in wards without evidence of C. difficile. This suggests that asymptomatic carriage among patients and HCWs can also contribute towards C. difficile transmission in hospitals. In conclusion, C. difficile can be transmitted via personal contact or via contaminated areas of the hospital environment.

Microbiological risk of anaesthetic breathing circuits after extended use.

INTRODUCTION: Daily change of breathing circuits in the operating theatre requires a lot of resources and is time and labour consuming. The extended use of breathing circuits could reduce the workload of the staff and health care costs. The aim of the present study was to evaluate the contamination rate of anaesthesia breathing circuits changed after 24, 48 or 72 h of use. MATERIALS: The study was performed as an experimental observational study. Microbiological samples were taken from 112 breathing systems including both parts of the ventilator circuit (inspiration and expiration) and analysed using microbiological standard techniques. Breathing circuits were changed according to three different schedules. In the 24-h group, breathing circuits were changed every day, whereas in the 48-h group changing of the circuits took place on Mondays, Wednesdays and Fridays. A period of 72 h operating use was tested on weekends. RESULTS: A total of 112 breathing systems comprised of 224 samples from the ventilator circuit were tested for bacteria and yeast contamination. A non-significant increase in the contamination rate was observed with the extended use for breathing circuits (24 h: 3.33%, 48 h: 4.35% and 72 h: 5.56%; P for trend=0.66). Similarly, no significant increase in contamination rate could be observed at the sample level (24 h: 1.67%, 48 h: 3.26% and 72 h: 2.78%; P for trend=0.71). CONCLUSION: The extended use of breathing circuits for 48 and 72 h does not increase significantly the risk of contamination, provided that HME filters are changed separately for every patient.

Mandibular bone remodelling in adults: evaluation of panoramic radiographs.

OBJECTIVES: To evaluate the changes in the antegonial angle, antegonial depth and gonial angle in edentulous and dentate patients in different age groups and between genders. METHODS: We evaluated 312 panoramic radiographs selected from our files. The images were grouped into four 10-year age groups (by decades). The youngest age group was 40-49 years and the oldest 70-79 years. Gender, dentition status and age were recorded. Measurements were made by two observers. RESULTS: No significant differences were observed for the gonial angle regarding age, gender and edentulism. For antegonial angle, the males (160.86 degrees +/-0.78) had significantly smaller values than females (165.08 degrees +/-0.58) irrespective of the dental status (P<0.0001). Edentulous individuals (161.51 degrees +/-0.83) had a smaller antegonial angle than dentate (165.05 degrees +/-0.76) and partially dentate (163.81 degrees +/-0.81) individuals (P<0.05). The antegonial depth was significantly greater for males than females (2.12 mm+/-0.09 vs 1.46 mm+/-0.07, P<0.0001). Edentulous individuals (1.87 mm+/-0.1) had significantly greater antegonial depth than dentate and partially dentate individuals (1.60 mm+/-0.1 and 1.65 mm+/-0.1, respectively). CONCLUSION: The gonial angle did not show any change with gender, age and dental status whereas the antegonial region had a resorptive pattern in the edentulous mandible. The morphology of the antegonial region was influenced by gender and dental status.