Rafael Guerra Lund

A systematic review about antibacterial monomers used in dental adhesive systems: Current status and further prospects.

OBJECTIVES This study systematically review the literature to assess the effectiveness of antibacterial monomers incorporated into dental adhesive systems against major oral bacteria; as well as the research advances and the future prospects of this technology. METHODS The following seven databases were screened: MedLine (PubMed), Lilacs, Ibecs, Web of Science, Scopus, Scielo, and The Cochrane Library. Furthermore, the online system Questel Orbit (Paris, France) was accessed to obtain patent data. The inclusion criteria were articles and patents that investigated the antimicrobial activity of antibacterial monomers in dental adhesive systems. Only documents written in English, Spanish or Portuguese were included. RESULTS After screening, 33 studies and eight patents fulfilled all the criteria and were included. Antibacterial agents, such as QA, MDPB, DMAHM and DMADDM were found in patents, which claimed their incorporation into adhesive compositions, dental cements, composite resins. MDPB was the only antimicrobial monomer incorporated into a commercially available adhesive system, Clearfil Protect Bond™ (Kuraray Co. Ltd., Japan). All studies reported the inclusion of antimicrobial monomers in adhesive systems to be an effective dental treatment strategy. SIGNIFICANCE There are potential areas to be explored with antibacterial monomers for dentistry, and their use could have important implications for future more conservative dental treatments. Although there is evidence of antibacterial activity from in vitro studies, clinical studies must be conducted to confirm the effectiveness of these materials in the prevention of dental pathologies.

Dissolving efficacy of some organic solvents on gutta-percha

The aim of this study was to evaluate the solubility of gutta-percha in four organic solvents used in endodontics. The solubility of gutta-percha (Dentsply) was assessed in xylol, orange oil, eucalyptol, chloroform and distilled water. A hundred and fifty samples of gutta-percha were prepared using a standardized stainless steel mould and divided into five groups for immersion in the different solvents tested and in distilled water (control group) for 2, 5 and 10 minutes. The means of gutta-percha dissolution in the solvents were obtained by the difference between the pre-immersion original weight and the post-immersion weight in a digital analytical scale (Gehaka-AG2000). Data were statistically analyzed by Analysis of Variance (ANOVA) and multiple comparisons with Scheffes test (p<0.05). The best solvency capacity was obtained with xylol. Chloroform, orange oil and eucalyptol presented similar results, and distilled water did not promote alterations in the gutta-percha.

Three-Year Clinical Performance of Composite Restorations Placed by Undergraduate Dental Students

This retrospective study evaluated the clinical performance and the reasons for failure of anterior and posterior composite restorations placed by undergraduate dental students over a 3-year period. All cavities were restored using Prime & Bond 2.1 and TPH (Dentsply), according to the manufacturers indications. One hundred and two patients who had received composite restorations by third and forth year undergraduate students were recalled and examined to analyze the quality of the restorations. The restorations were evaluated using the modified USPHS system. Two hundred and fifty-six composite restorations, 170 in anterior teeth and 86 in posterior teeth, were evaluated. Eighty-five percent of the restorations were considered satisfactory after 3 years. Class II and class IV restorations presented the highest prevalence of failure. Loss of the restoration and deficient marginal adaptation were the main causes of failure. No restoration failed due to secondary caries. Most restorations placed by dental students were considered satisfactory after long-term evaluation. Failure was more prevalent in larger restorations and was not associated with secondary caries.

An ethnomedicinal survey on phytotherapy with professionals and patients from Basic Care Units in the Brazilian Unified Health System.

ETHNOPHARMACOLOGICAL RELEVANCE In this study, an ethnomedicinal survey was conducted in the city of Pelotas, Brazil, with professionals and patients in the Unified Health System (SUS). With the approval of the National Policy on Medicinal Plants and Herbal Medicines, and with the adoption of a National Policy on Integrative and Complementary Practices in the SUS in Brazil, there is growing concern regarding Brazilian medicinal plants and their proper use in medicine. The expansion of the therapeutic options offered to the users of the SUS includes access to medicinal plants and herbal drugs, as well as related services, such as phytotherapy. For improving health and for the social inclusion of phytotherapies, safety, efficacy, and quality are important strategies. MATERIALS AND METHODS Interviews of both professionals and patients were conducted at five Basic Care Units, and a sample size of 393 was obtained. RESULTS Of the patients attending the Basic Care Units, 91.6% had experienced the use of medicinal plants at least once to treat certain diseases. Of the professionals, 65% had used medicinal plants but only 10% prescribed phytotherapeutics to their patients. Generally, the users were homemakers (26%) of the female gender (71.5%) who were older than 60 years (26%) and had a family income between 1 and 2 Brazilian minimal salaries. The professionals were predominantly female (80%), and a high proportion (80%) believed in the positive effects of phytotherapy (80%), even though these professionals had not been taught phytotherapy as undergraduate students (75%) and had not discussed the topic with their teachers (85%). Patients (81.5%) and professionals (45%) reported that their knowledge of medicinal plants came from their parents or grandparents. From a total of 66 different herbs used by the subjects, mauve (24%) was the most commonly used, often to treat toothaches (24.2%). CONCLUSION It is concluded that a high proportion of users and professionals made use of medicinal plants, and of the large number of plants mentioned in the questionnaire, mauve was the most commonly used, mainly for the treatment of toothaches. The major source of the transmission of knowledge concerning herbal medicine was parents or grandparents.

Vinte e quatro meses de heterocontrole da fluoretação das águas de abastecimento público de Pelotas, Rio Grande do Sul, Brasil

O objetivo deste estudo foi monitorar, mensalmente, os niveis de fluor na agua de abastecimento publico de Pelotas, Rio Grande do Sul, Brasil, bem como verificar a validade da formacao de grupos de heterocontrole. Pelotas foi dividida em 16 pontos geograficos, incluindo as tres Estacoes de Tratamento da agua e a coleta foi feita de novembro de 1999 a outubro de 2001, em duplicata. Apos a coleta, as amostras foram enviadas ao Laboratorio de Vigilância Sanitaria de Fluor da Universidade do Vale do Itajai, onde a analise foi feita utilizando-se o metodo eletrometrico (Orion 920A/Eletrodo Orion 9609). Apos 24 meses, 764 unidades amostrais foram coletadas e verificou-se uma inconstância nos resultados, predominando niveis insuficientes de fluor ate o primeiro trimestre de 2001, quando houve um significativo aumento no numero de unidades amostrais com uma concentracao de fluor ideal (0,6-0,9ppmF), porem, ha o surgimento de pontos revelando um excesso de fluoretos (> 1ppmF). Os resultados permitiram concluir que o heterocontrole e fundamental para buscar a manutencao de um correto programa de FAAP.O objetivo deste estudo foi monitorar, mensalmente, os niveis de fluor na agua de abastecimento publico de Pelotas, Rio Grande do Sul, Brasil, bem como verificar a validade da formacao de grupos de heterocontrole. Pelotas foi dividida em 16 pontos geograficos, incluindo as tres Estacoes de Tratamento da agua e a coleta foi feita de novembro de 1999 a outubro de 2001, em duplicata. Apos a coleta, as amostras foram enviadas ao Laboratorio de Vigilância Sanitaria de Fluor da Universidade do Vale do Itajai, onde a analise foi feita utilizando-se o metodo eletrometrico (Orion 920A/Eletrodo Orion 9609). Apos 24 meses, 764 unidades amostrais foram coletadas e verificou-se uma inconstância nos resultados, predominando niveis insuficientes de fluor ate o primeiro trimestre de 2001, quando houve um significativo aumento no numero de unidades amostrais com uma concentracao de fluor ideal (0,6-0,9ppmF), porem, ha o surgimento de pontos revelando um excesso de fluoretos (> 1ppmF). Os resultados permitiram concluir que o heterocontrole e fundamental para buscar a manutencao de um correto programa de FAAP.The aim of the present study was monthly evaluation of fluoride levels in the public water supply in Pelotas, Rio Grande do Sul State, Brazil, and the validity of forming external control groups. Pelotas was divided into 16 geographic regions, including the three public water treatment stations. Water samples were collected from November 1999 to October 2001. Two samples were drawn from each region. Samples were sent to the Fluoride Health Surveillance Laboratory at Universidade do Vale do Itajaí. Fluoride analysis used an electrometric method (Orion 920 A/Electrometer Orion 9609). After 24 months, 764 samples were collected, demonstrating a discontinuity in the fluoride levels. There was an increase in the number of samples with an ideal concentration of fluoride. However, several points with excessive fluoride levels (> 0.9ppmF) also appeared. Based on these results it was concluded that external control is essential for monitoring fluoride levels in the public water supply.

Occurrence, isolation and differentiation of Candida spp. and prevalence of variables associated to chronic atrophic candidiasis.

The purpose of this study was to survey the frequency of Candida spp. in patients with chronic atrophic candidiasis (CAC), to differentiate Candida species and to assess the prevalence of certain infection‐associated variables to this disease. Patients with CAC and wearing partial or complete dentures were recruited. Data were obtained by means of a questionnaire with details involving identification of the subject, demographic characteristics, behaviour and medical history, clinical and mycological evaluation and identification of yeast. The sample collection was carried out in the palate or palate and tongue of the subjects using sterilised swabs. Data were submitted to statistical analyses using Fischer’s test. Forty‐three (53%) cases of CAC showed the presence of Candida albicans. Females (75.2%) wearing complete dentures (60.1%) for more than 10 years (58%) were risk factors to CAC development. It could be concluded that: (a) the results did not confirm a significant difference among patients with CAC concerning the presence or absence of Candida spp.; (b) the occurrence of Candida was negatively related to important factors associated to this opportunistic infection; and (c) mycological findings did not indicate that the variables investigated have a significant effect on oral infections by C. albicans or other Candida species.

The effectiveness of current dentin desensitizing agents used to treat dental hypersensitivity: a systematic review.

OBJECTIVE Dentin desensitizing agents are used in the treatment of dentin hypersensitivity, which is defined as a painful response in the exposed dentin to stimuli that are thermal, evaporative, tactile, osmotic, or chemical. A systematic review was conducted to analyze the clinical effectiveness of current desensitizer with at least 3 months of follow-up. METHOD AND MATERIALS Eight electronic databases were searched: MedLine (PubMed), Embase, Lilacs, Ibecs, Web of Science, Scopus, Scielo, and The Cochrane Library. Only those clinical trials published from 2000 to 2012 were included. RESULTS A total of 3,029 relevant records were identified. After title and abstract examination, 2,645 articles were excluded. A data extraction form was designed and completed by reviewers from the selected studies for a retrospective comparison. From the 99 studies retrieved for detailed review, only 17 had an evaluation time of at least 3-months follow-up and fulfilled the selection criteria. CONCLUSION Cervitec Plus, SE Bond & Protect Liner F, laser, and iontophoresis have shown satisfactory posttreatment results between 3 and 6 months. However, additional clinical trials are warranted to better compare the different types of treatments and their effectiveness in the longer term.

Self-etching dental adhesive containing a natural essential oil: anti-biofouling performance and mechanical properties

This study assessed the anti-biofouling performance of an experimental adhesive system containing a naturally occurring essential vegetable oil and examined the following physical and mechanical properties: water sorption (WS) and solubility (SL), microtensile bond strength to dentin (μTBS), and degree of conversion. The following six groups were tested: a self-etching experimental adhesive containing refined essential oil from the seeds of the Butia capitata tree (EAO); an oil-free version of the experimental adhesive (EANO); one group without adhesive as the control (C); and the three following commercial self-etching adhesives: Clearfil Protect Bond (CPB), Clearfil SE Bond, and Adper SE Plus. The antibacterial effect was estimated by microbiological culture on selective/non-selective media, and the results expressed as colony-forming units per unit weight of dry biofilm (CFU mg−1). The data were submitted to ANOVA and Tukey’s post hoc test (α = 0.05). After 24 h, pH changes were similar in the storage medium of all tested adhesive systems. EAO showed similar levels of antimicrobial activity in a model biofilm microcosm as the commercial self-etching adhesive CPB. Both were effective against total microorganisms, aciduric bacteria, lactobacilli, and Streptococcus mutans. WS and SL were not affected by the presence of the essential oil; the values of EAO were similar to or less than those of commercial equivalents. The incorporation of an essential oil into an experimental adhesive did not influence its monomer conversion result. Immediate μTBS values of EAO and EANO were similar and were greater than those of commercial equivalents. After storage for 6 months, the μTBS of the EAO decreased significantly and became similar to the values of commercial equivalents, while the strength of the EANO was not affected.

Antiproliferative activity of flower hexane extract obtained from Mentha spicata associated with Mentha rotundifolia against the MCF7, KB, and NIH/3T3 cell lines.

This study assessed the antiproliferative effect in vitro of the flower hexane extract obtained from Mentha spicata associated with Mentha rotundifolia against the human breast adenocarcinoma (MCF-7), human mouth epidermal carcinoma (KB), and mouse embryonic fibroblast (NIH 3T3) cell lines, using sulforhodamine B (SRB) assay. A cell density of 2×10(4)/well was seeded in 96-well plates, and samples at different concentrations ranging from 10 to 500 mg/mL were tested. The optical density was determined in an ELISA multiplate reader (Thermo Plate TP-Reader). Results demonstrated that the hexane extract presented antiproliferative activity against both the tumor cell lines KB and MCF-7, presenting a GI(50) (MCF-7=13.09 mg/mL), TGI (KB=37.76 mg/mL), and IL(50) (KB=291.07 mg/mL). Also, the hexane extract presented antiproliferative activity toward NIH 3T3 cells GI(50) (183.65 mg/mL), TGI (280.54 mg/mL), and IL(50) (384.59 mg/mL). The results indicate that the flower hexane extract obtained from M. spicata associated with M. rotundifolia presents an antineoplastic activity against KB and MCF-7, although an antiproliferative effect at a high concentration of the extract was observed toward NIH 3T3.

Clinical Performance and Wear Resistance of Two Compomers in Posterior Occlusal Restorations of Permanent Teeth: Six-Year Follow-up

This study evaluated the clinical performance and wear resistance of compomer restorations placed in the occlusal cavities of posterior permanent teeth after six years. In 1999, 72 Class I restorations were placed by a single operator in 33 patients. Eighty-two percent of these restorations were located in molars. Each patient received at least two restorations, one with F2000 (3M ESPE) and another with Dyract AP (Dentsply). The finished and polished restorations that were free of any failure were considered the baseline. The restorations were clinically evaluated at baseline and at one-, two- and six-year intervals using modified USPHS criteria for color mismatch, marginal discoloration, surface roughness, marginal adaptation, anatomic form and secondary caries. Polyvinylsiloxane impressions (Express, 3M ESPE) were also taken, and models were obtained for indirect wear assessment (Leinfelder scale) at the same intervals. After six years, 11 patients attended the recall. Twenty-seven compomer restorations (11 with Dyract and 16 with F2000) were reevaluated. Data were submitted to the Friedmans test, ANOVA with repetitive measures, Tukeys test (clinical data), Wilcoxon and Kruskal-Wallis tests and the Spearmans correlation test (wear evaluation), all at a significance level of p < 0.05. When comparing the materials, F2000 and Dyract presented similar clinical performance and occlusal wear at the end of the clinical trial. The two compomers showed a significant increase in wear at the six-year follow-up, and a positive correlation (r2 = 0.65) was detected between wear and evaluation time (p < 0.001). Despite the decrease in restoration quality and the increase in occlusal wear, nearly all restorations were considered acceptable after the six-year evaluation.