Influence of gender on periodontal outcomes: A retrospective analysis of eight randomized clinical trials.

AIMS: To explore the influence of gender on periodontal treatment outcomes in a dataset of eight RCTs conducted in Brazil, United States, and Germany. METHODS: Clinical parameters were compared between men and women with stages III/IV grades B/C generalized periodontitis at baseline and 1-year post-therapy, including scaling and root planing with or without antibiotics. RESULTS: Data from 1042 patients were analyzed. Men presented a tendency towards higher probing depth (p = .07, effect size = 0.11) and clinical attachment level (CAL) than women at baseline (p = .01, effect size = 0.16). Males also presented statistically significantly lower CAL gain at sites with CAL of 4-6 mm at 1-year post-therapy (p = .001, effect size = 0.20). Among patients with Grade B periodontitis who took antibiotics, a higher frequency of women achieved the endpoint for treatment (i.e., ≤4 sites PD ≥5 mm) at 1 year than men (p < .05, effect size = 0.12). CONCLUSION: Men enrolled in RCTs showed a slightly inferior clinical response to periodontal therapy in a limited number of sub-analyses when compared to women. These small differences did not appear to be clinically relevant. Although gender did not dictate the clinical response to periodontal treatment in this population, our findings suggest that future research should continue to explore this topic.

Antibacterial Activity of a Bioactive Tooth-Coating Material Containing Surface Pre-Reacted Glass in a Complex Multispecies Subgingival Biofilm.

Bioactive materials were developed with the ability to release fluoride and provide some antimicrobial potential, to be widely used in dentistry today. However, few scientific studies have evaluated the antimicrobial activity of bioactive surface pre-reacted glass (S-PRG) coatings (PRG Barrier Coat, Shofu, Kyoto, Japan) on periodontopathogenic biofilms. This study evaluated the antibacterial activity of S-PRG fillers on the microbial profile of multispecies subgingival biofilms. A Calgary Biofilm Device (CBD) was used to grow a 33-species biofilm related to periodontitis for 7 days. The S-PRG coating was applied on CBD pins from the test group and photo-activated (PRG Barrier Coat, Shofu), while the control group received no coating. Seven days after treatment, the total bacterial counts, metabolic activity, and microbial profile of the biofilms were observed using a colorimetric assay and DNA-DNA hybridization. Statistical analyses were applied; namely, the Mann-Whitney, Kruskal-Wallis, and Dunn's post hoc tests. The bacterial activity of the test group was reduced by 25.7% compared with that of the control group. A statistically significant reduction was observed for the counts of 15 species: A. naeslundii, A. odontolyticus, V. parvula, C. ochracea, C. sputigena, E. corrodens, C. gracilis, F. nucleatum polymorphum, F. nucleatum vincentii, F. periodonticum, P. intermedia, P. gingivalis, G. morbillorum, S. anginosus, and S. noxia (p ≤ 0.05). The bioactive coating containing S-PRG modified the composition of the subgingival biofilm in vitro, thereby decreasing colonization by pathogens.

Whole Tooth Regeneration: Can Animal Studies be Translated into Clinical Application?

Tooth loss leads to several oral problems and although a large number of treatments have been proposed to rehabilitate partially or totally edentulous patients, none of them is based on replacement of a missing tooth by a new natural whole tooth. In the field of tissue engineering, some animal models have been developed to regenerate a natural tooth in the oral cavity. This review shows the state of the art in whole tooth regeneration based on data from in vivo studies. A systematic scoping review was conducted to evaluate studies that described whole-tooth regeneration and eruption in the oral cavity. The data demonstrated that over 100 animals were used in experimental studies and all of them received implants of tooth germs constructed by bioengineering processes. Mini pigs and pigs were used in four studies followed by mice (n = 1) and dog (n = 1). Over 58 (44%) animals showed whole tooth eruption around 3.5 months after tooth germ implantation (1 to 13.5 months). Most of specimens revealed the presence of odontoblasts, dentin, dentinal tubules, dental pulp, root analogue, cementum, blood vessels, and alveolar bone. It could be concluded that in vivo whole tooth regeneration was proved to be possible, but the challenge to overcome translational barriers and test these approaches in humans still remains. Impact Statement Advances in tissue engineering have led to the development of new methods to regenerate and replace tissues and organs, including teeth. Tooth regeneration is the main goal for the replacement of tooth loss and therefore current evidence showed that tissue engineering might provide this treatment in future.

Análise da microdureza de diferentes materiais restauradores

Objetivo: realizar um ensaio in vitro de microdureza em diferentes materiais restauradores. Métodos: Para cada material restaurador (FUJI IX - Cimento de Ionômero de Vidro; Tetric - resina composta convencional; Beautifil II; resina composta bioativa) foram confeccionadas 10 restaurações em dentes incisivos bovinos, cavitados por uma ponta diamantada 2092 KG Sonrensen, seguindo as recomendações de cada fabricante. O ensaio de microdureza foi realizado em diferentes profundidades (superfície, 0.4mm, 1.0mm, 2.0mm, 3.0mm e 4.0mm) e em dois momentos, imediatamente e 24h após a fotoativação. Os dados foram analisados pelo teste de análise de variância (ANOVA) e teste Tukey. Resultados: As médias de microdureza diminuíram significativamente com o aumento da profundidade, com valores mais baixos no primeiro momento avaliado. A resina composta bioativa apresentou as maiores médias de microdureza. Conclusão: os materiais testados apresentaram diminuição gradual da microdureza com o aumento da profundidade, sendo mais acentuada em profundidades acima de 2.0mm. Em todos os materiais restauradores, as médias de microdureza mais altas foram registradas 24 horas após a fotoativação. A resina composta bioativa apresentou os melhores resultados nas diferentes profundidades avaliadas.

Influência da polimerização na estabilidade de cor de resinas compostas

Objetivo: Avaliar a influência da polimerização na estabilidade de cor de resinas compostas. Métodos: Avaliou-se o efeito da polimerização na cor de 14 resinas compostas: Empress Direct - A2E; Empress Direct - A2D; Empress Direct - Trans Opal; Vittra - EA2; Vittra - DA2; Vittra - Trans OPL; Essentia ­ LE; Essentia ­ LD; Essentia - OM; Filtek ­ AE2; Filtek - A2D; Filtek ­AT; Grandioso - A2; FillMagic - B2 Dentin. As resinas compostas foram inseridas em incremento único (n=5) em matrizes de 5X2mm (diâmetro x altura). Foi realizada a avaliação de cor pelos parâmetros CIE L*a*B* (AC) em triplicata com um espectrofotômetro (Easy Shade, Vita). As resinas compostas foram ativadas de acordo com as recomendações dos fabricantes e avaliadas imediatamente e após 24h em estufa a 37oC. Foi calculado o ΔE, analisado por 2-way ANOVA e teste de Bonferroni (p<0,05). Resultados: Observou-se interação significativa entre resina*tempo, todas resinas compostas apresentaram mudança de cor após a polimerização. Conclusão: Pode-se concluir que há mudança de cor após a ativação das resinas compostas e essa cor pode mudar após 24h em umidade.

In vitro evaluation of enamel surface roughness and morphology after orthodontic debonding: Traditional cleanup systems versus polymer bur.

INTRODUCTION: The primary aim of this randomized in vitro study was to compare the effectiveness of carbide, fibreglass and polymer burs on resinous remnant removal after bracket debonding, by the evaluation of enamel surface roughness and morphology. The secondary objective was to compare the time dispended on the procedures. METHODS: The buccal surfaces of 28 bovine incisors were analysed by a profilometer to initial roughness measurement (Ra-T1). Brackets were bonded with a light-cured resin and debonded with a debonding plier. The samples were randomly divided into four groups, according to the bur used (n=7): A-Tungsten carbide; B-Fibreglass; C-Polymer; D-Polymer with 75% ethanol pre-treatment. The second roughness measurements were made after resin removal (Ra-T2). Time for removal procedures was also recorded. The third measurements were made after polishing (Ra-T3). Scanning Electronic Microscopy was performed in two samples of each group: after resin removal and after polishing. Results of roughness and time measurements were statically analysed by analysis of variance with post-hoc Bonferroni. RESULTS: After polishing, tungsten carbide (P=0.1555) and fibreglass burs provided final surface roughness statistically similar to the baseline condition (P=1.0000). Yet, polymer burs, associated (P<0.0001) or not to alcohol (P<0.0001), provided surface roughness significantly higher when compared to baseline values. Polymer burs were more time-consuming on resinous remnant removal than tungsten carbide and fibreglass burs (P<0.05). CONCLUSION: Polymer burs were less effective and more time-consuming to remove the remaining resin than tungsten carbide and fibreglass burs. The polishing step created smoother surfaces regardless of the burs used for resin removal.

Biogenic synthesis and antimicrobial activity of silica-coated silver nanoparticles for esthetic dental applications.

OBJECTIVES: this study aimed to synthesize AgNPs from green tea (GT) extract, forming GT-AgNPs, and to coat their surfaces with silica, resulting in light-colored Ag@SiO2 nanoparticles. MATERIALS AND METHODS: particles were characterized and tested for minimal inhibitory concentration (MIC), biofilm formation against Streptococcus mutans and cytotoxicity evaluation on dental pulp fibroblasts. RESULTS: X-ray diffraction (XRD) confirmed the formation of pure AgNPs, whereas energy dispersive X-ray spectroscopy (EDS) mapped their elemental atoms. Dynamic light scattering (DLS) demonstrated formation of particles at nanoscale, with moderate polydispersity and negative zeta potential, in agreement with nanoparticle tracking analysis (NTA) size measurements. Fourier-transformed infrared (FTIR) spectroscopy confirmed the successful condensation of silica, which significantly increased surface area by 50%, as assayed by surface area analysis (BET). Thermogravimetric analysis showed a 18%-mass of silica on the surface of Ag@SiO2NPs. Transmission electron microscopy (TEM) displayed the spherical shape of nanoparticles and average size of 11 nm for GT-AgNPs and Ag@SiO2NPs. Ag@SiO2NPs demonstrated potent antimicrobial action against S. mutans, with MIC determined as 600 µg/mL, and inhibition of approximately 44% (p < 0.05) of biofilm formation. At the MIC concentrations, both NPs did not exhibit cytotoxicity. CONCLUSION: Ag@SiO2NPs might have a useful application in dental materials. CLINICAL SIGNIFICANCE: The possibility of incorporating antimicrobial properties in restorative materials without compromising esthetics makes the AgNPs@SiO2 NPs promising agents against S. mutans biofilm formation, hence the prevention of dental caries. This represents a great step towards the development of more interactive biomaterials in dentistry to overcome clinical problems.

Subgingival microbial profile of women with breast cancer: a cross-sectional study

Background: Some prospective studies have observed associations between periodontal disease and breast cancer. Therefore, the aim of the present study was to investigate the composition of the subgingival biofilm of women diagnosed with breast cancer, who also presented with chronic periodontitis. Methods: All subjects underwent clinical and microbiological assessment. Subgingival biofilm samples were taken from at least three sites of 44 women who had breast cancer. The mean levels and proportions of 40 bacterial species were determined by checkerboard DNA-DNA hybridization. Spearman correlation was used to assess possible associations between the mean levels of bacterial species and clinical conditions. Results: The five species found at the highest levels were Prevotella nigrescens, Actinomyces gerencseriae, Neisseria mucosa, Porphyromonas gingivalis and Tannerella forsythia. The species detected in the lowest counts were Propionibacterium acnes, Streptococcus constellatus, Streptococcus intermedius, Eubacterium saburreum and Streptococcus anginosus. No significant association between levels and proportion of bacterial species and clinical parameters were found. Conclusion: In conclusion, the results of the present study found no direct association between the subgingival microbiota and breast cancer and an indirect pathway should be addressed in further studies.