Influence of concentration, irrigation method, and root canal third on intratubular penetration of sodium hypochlorite - a broad statistical analysis.

Background: The permanence of microorganisms in the root canal system represents the main cause of endodontic failure. Considering the impossibility of effective action of the endodontic files in ramifications of the main canal and mainly inside the dentinal tubules, a better understanding of the irrigation dynamics to enhance endodontic prognosis is essential. Objective: To evaluate the depth of intratubular penetration values of sodium hypochlorite (NaOCl) (dependent variable) by comparing different concentrations, methods of irrigation, and root canal thirds (independent variables) and to investigate the existence of interactions among them, capable of influencing the dependent variable. Material and Methods: 40 roots from extracted human maxillary central incisors were stained and instrumented according to four irrigation protocols (n. 10): conventional irrigation (CI) at each use or change of instrument, and final irrigation with 5ml of 2.5% or 5.25% NaOCl, with or without passive ultrasonic irrigation (PUI), respectivelly. Measurements based on stereomicroscopic images were obtained, and the data were subjected to statistical analysis (p< 0.05). Results: The highest depth values of intratubular penetration of NaOCl were observed in the cervical third, at 5.25%, and by PUI. When only two independent variables were analyzed in association, the highest penetration depth values of NaOCl were obtained at 5.25%, regardless of irrigation method, at 5,25%, in the cervical third, and; in the cervical third, despite of irrigation method. Considering the three independent variables simultaneously, the highest depth values of intratubular penetration of NaOCl were observed in the cervical third, at 5.25%, no matter the irrigation method. The interaction between the independent variables on the penetration depth values of NaOCl was only confirmed considering the irrigation method and root canal third. Conclusions: Intratubular penetration of NaOCl was influenced by the three independent variables individually and when the irrigation method and root canal third were considered simultaneously. Key words:Dentinal tubules, Depth, Disinfection, Irrigation, Root canal system, Sodium hypochlorite.

Clinical determination of anatomical diameter in different dental groups correlating them with gender, age, tooth/canal and pulpoperiradicular diagnosis: an observational clinical study.

The aim of this observational clinical study (OCS) was to determine the clinical anatomical diameter (CAD) in several dental groups, thus correlating them with gender, age, tooth/canal and pulpoperiradicular diagnosis. Three-hundred fifty-nine teeth/584 vital or necrotic root canals from patients of both genders and different ages composed the sample. After performing the necessary previous procedures, K-Flexofiles were used to determine the CAD. Then, the gender and age of the patients, as well as the pulpoperiradicular diagnosis of the teeth were tabulated to conduct the statistical analysis (p < 0.05). Of the 359 teeth/584 root canals evaluated, 208/342 were from women (mean age 38.85 ± 13.42 years) and 151/242 were from men (mean age 45.41 ± 14.90 years). Statistically significant differences between the CAD means of root canals from women and men were not identified (p = 0.411). The analysis of the correlation between the CAD and age also showed a total independence (p = 0.271). Teeth with pulp necrosis and asymptomatic apical periodontitis diagnosed radiographically (TPNAAPDR) had a significantly larger CAD mean than teeth with pulp necrosis and no asymptomatic apical periodontitis diagnosed radiographically (TPNNAAPDR) and teeth with vital pulp and normal apical tissues (TVPNAT) (p = 0.0297); and the last two did not differ statistically (p > 0.05). The largest CAD mean was observed in single canals of maxillary central incisors. The lowest values of this variable were identified in the mesiobuccal and mesial canals of maxillary and mandibular first molars, respectively. The CAD of the root canals was influenced only by the root canal/tooth and pulpoperiradicular diagnosis.

Avaliação dos selantes de fossas e fissuras aplicados por estudantes de Odontologia / Evaluation of pit and fissure sealants applied by dental students

Introdução: Selantes de fossas e fissuras são indicados para prevenir lesão de cárie em superfícies oclusais. Objetivo: O objetivo deste estudo foi avaliar os selantes de fossas e fissuras aplicados por estudantes do Curso de Graduação em Odontologia da Universidade Regional de Blumenau (FURB), Santa Catarina. Material e Método: O estudo descritivo retrospectivo desenvolveu-se em três etapas: na primeira, procedeu-se à análise dos prontuários do Setor de Triagem, tendo como critério de inclusão a existência de radiografias dos dentes selados. Na segunda etapa, analisaram-se as radiografias dos prontuários selecionados e a história clínica da criança. A terceira etapa foi realizada por meio de exames clínicos e radiográficos, pelos quais eram verificadas as condições dos selantes de fossas e fissuras. Resultado: Foram analisados 800 prontuários, sendo selecionados 131 (16,37%) para a segunda etapa, quando se observou que 321 selantes de fossas e fissuras foram aplicados. Compareceram à consulta de controle 119 (90,84%) crianças, ocasião em que se confirmou a aplicação de 160 (49,85%) selantes resinosos, 126 (39,25%) com cimento de ionômero de vidro e 35 (10,90%) com resina flow. Foram observados 296 (92,21%) selantes em dentes permanentes. Ao exame clínico, verificou-se que 114 (35,51%) selantes haviam sido perdidos totalmente em diferentes períodos de tempo. Nenhuma lesão de cárie foi observada em 294 (91,59%) dentes selados. Conclusão: Verificou-se que os selantes de fossas e fissuras, aplicados por estudantes do Curso de Odontologia da FURB, foram eficazes na manutenção da maioria das superfícies dentárias livres de lesão de cárie, mesmo quando foram perdidos parcial ou totalmente.

Introduction: Pit and fissure sealants are indicated to prevent caries in occlusal surfaces. Objective: The aim of this study was to evaluate pit and fissure sealants applied by Dentistry undergraduate students of the Regional University of Blumenau (FURB), Santa Catarina. Material and Method: The retrospective descriptive study was developed in three stages: the analysis of the records of the Department of Screening, being used as an inclusion criterion the existence of X-rays of the sealed teeth. In the second step we analyzed the radiographs of selected records and medical history of the child. The third step was performed by clinical and radiographic examinations, when conditions of pit and fissure sealants were verified. Result: We analyzed 800 medical records, and selected 131 (16.37%) for the second step, where it was observed that 321 pit and fissure sealants were applied. 119 (90.84%) children attended the control dental appointment, when confirmed the application of 160 (49.85%) resin, 126 (39.25%) glass ionomer cement and 35 (10.90%) flowable composite. We observed 296 (92.21%) sealants in permanent teeth. The clinical examination revealed that 114 (35.51%) of the sealants were completely lost at different periods of time. No caries lesion was observed in 294 (91.59%) teeth sealed. Conclusion: It was found that the pit and fissure sealants applied by students of the FURB School of Dentistry were effective in maintaining the majority of tooth surfaces free of caries, even when they were partially or totally lost.

Degradation of the resin-dentin bonds after simulated and inhibited cariogenic challenge in an in situ model.

The aim of this study was to evaluate the resin-dentin bonds of two simplified etch-and-rinse adhesive after simulated cariogenic and inhibited cariogenic challenge in situ. Dental cavities (4 mm wide, 4 mm long, and 1.5 mm deep) were prepared in 60 bovine teeth with enamel margins. Restorations were bonded with either adhesive Adper Single Bond 2 (3MESPE) or Optibond Solo Plus (Kerr). Forty restorations were included in an intra-oral palatal appliance that was used for 10 adult volunteers while the remaining 20 dental blocks were not submitted to any cariogenic challenge [NC group] and tested immediately. For the simulated cariogenic challenge [C+DA], each volunteer dropped 20% sucrose solution onto all blocks four times a day during 14 days and distilled water twice a day. In the inhibited cariogenic challenge group [C + FA], the same procedure was done, but slurry of fluoride dentifrice (1.100 ppm) was applied instead of water. The restored bovine blocks were sectioned to obtain a slice for cross-sectional Vickers microhardness evaluation and resin-dentin bonded sticks (0.8 mm(2)) for resin-dentin microtensile evaluation. Data were evaluated by two-way ANOVA and Tukey's tests (α = 0.05). Statistically lower microhardness values and degradation of the resin-dentin bonds were only found in the C + DW group for both adhesives. The in situ model seems to be a suitable short-term methodology to investigate the degradation of the resin-dentin bonds under a more realistic condition.

Avaliação das alterações em cimentos de ionômero de vidro após escovação simulada com dentifrícios de diferentes abrasividades / Evaluation of changes on glass ionomer cements after simulate toothbrushingwith dentifrices of different abrasiveness

Introdução: O objetivo deste estudo foi avaliar alterações de massa e de rugosidade superficial em cimentos de ionômero de vidro (CIVs) submetidos à escovação simulada com dentifrícios contendo diferentes abrasivos. Material e método: Foram testados dois cimentos e dois dentifrícios. O CIV de alta viscosidade (Ketac Molar EasymixTM-3M ESPE) e o CIV modificado por resina (VitremerTM-3M ESPE) foram submetidos à escovação com dentifrícios contendo sílica associada ao dióxido de titânio (Oral B Pró-Saúde®-Procter & Gamble do Brasil) ou ao carbonato de cálcio (Condor 100% Branco®-Condor) e água destilada (controle). De cada material, foram preparadas 30 amostras (diâmetro = 6 mm e espessura = 5 mm) de acordo com as instruções do fabricante. Os espécimes foram mantidos em água destilada, a 37 °C por 24 horas, antes de mensurar a massa e a rugosidade de superfície iniciais. Depois, foram submetidos à escovação simulada (20.000 ciclos de escovação) com os dentifrícios e a água. A alteração de massa (diferença entre massa inicial e final) foi obtida em balança analítica (0,0002 g de precisão). As médias iniciais e finais de rugosidade de superfície foram verificadas em cada espécime após cinco leituras consecutivas em um rugosímetro antes e após escovação. Os dados foram analisados pelo teste ANOVA dois critérios. Resultado: A perda de massa para ambos os materiais foi significantemente maior com a associação sílica-dióxido de titânio (p < 0,05). O CIV modificado por resina apresentou maior rugosidade inicial quando comparado ao de alta viscosidade (p < 0,05). Conclusão: Dentifrícios abrasivos determinam acentuada perda de massa e aumento na rugosidade em cimentos ionoméricos, sendo o potencial de desgaste diferente entre os materiais.

Introduction:The aim of this study was to assess changes in weight and surface roughness of glass ionomer cements (GICs) submitted to simulated toothbrushing with dentifrices containing different abrasives. Material and method: Two glass ionomer cements (GIC) and two dentifrices were tested: a high viscosity GIC (Easymix Ketac MolarTM-3M Espe); a resin modified GIC (VitremerTM-3M ESPE); dentifrices with silica associated to titanium dioxide (Oral B Pro Health-Procter & Gamble-Brazil) or to calcium carbonate (Condor 100% White) and distilled water (control). Of each material, 30 samples were prepared (diameter = 6 mm and thickness = 5 mm) according to manufacturers` instructions. The specimens were kept in distilled water, at 37 °C, for 24 hours, before taking the measurements of the initial weight and surface roughness. After this, they were submitted to simulated toothbrushing (20,000 cycles of brushing) with the dentifrices or water. The mass loss assessment (difference between initial and final mass) was obtained by analytical scale (0.0002 g accuracy). Initial and final mean surface roughness were obtained from each specimen after 5 consecutive readings using a surface profilometer before and after brushing. Data were analyzed by two-way ANOVA. Result: The mass loss for both materials was significantly higher when using titanium dioxide abrasive agent (p < 0.05). The resin modified GIC showed higher initial roughness compared to high viscosity GIC (p < 0.05). Conclusion: Abrasive toothpastes established pronounced mass loss and increased roughness in glass ionomer cements, and the potential of wear differed between materials.

Influência dos ciclos de escovação sobre a perda de massa e a rugosidade superficial de cimentos de ionômero de vidro / Influence of brushing cycles on weight loss and roughness of the glass ionomer cements

O objetivo deste estudo foi avaliar a perda de massa e a rugosidade superficial em cimentos de ionômero de vidro pela escovação simulada com 20.000 e 50.000 ciclos de escovação. Material e método: Dois cimentos de ionômero de vidro foram testados: um de alta viscosidade (Ketac™ Molar Easymix-3M ESPE) e um modificado por resina (Vitremer™- 3M ESPE). Dez amostras (diâmetro = 6 mm e espessura = 5 mm) de cada material foram preparadas de acordo com as instruções dos fabricantes. Os espécimes foram armazenados em água destilada, a 37 °C, até obtenção de uma massa constante, sendo submetidos à escovação simulada. A avaliação da perda de massa (diferença entre inicial e final) foi obtida por balança analítica (0,0002 g de precisão). Os valores de rugosidade superficial inicial e final foram obtidos para cada amostra após cinco leituras, usando um rugosímetro antes e após a escovação. Os dados foram analisados pelo teste ANOVA a dois critérios. Resultado: Os valores de massa inicial foram similares para ambos os materiais, sem perda significativa de massa após a escovação simulada com 20.000 e 50.000 ciclos (p > 0,05). O cimento de ionômero de vidro modificado por resina apresentou maior rugosidade superficial, sendo que o valor inicial (1,37 ± 0,24 µm) aumentou significativamente (p < 0,001) após 20.000 (2,98 ± 1,38 µm) e 50.000 ciclos (3,43 ± 2,29 µm), mas não houve diferença estatística entre os ciclos. Conclusão: Os diferentes ciclos de escovação não resultaram em perda de massa dos materiais, mas houve aumento na rugosidade superficial do cimento de ionômero de vidro modificado por resina.

The aim of this study was to assess the influence of brushing cycles on weight loss and roughness of the glass ionomer cements by simulated toothbrushing using 20,000 and 50,000 cycles of brushing. Material and method: Two GICs were tested: a high viscosity (Easymix Ketac™ Molar- 3M Espe) and a resin modified (Vitremer™- 3M ESPE). Ten samples (diameter = 6 mm and thick = 5 mm) of each material were prepared according to manufacturers' instructions. The specimens were kept in distilled water, at 37 °C, until the mass was stabilized. After that, they were submitted to simulated toothbrushing. The weight loss assessment (difference between initial and final) was obtained by analytical scale (0.0002 g accuracy). Initial and final mean surface roughnesses were obtained from each specimen after 5 consecutive readings using a surface profilometer before and after brushing. Data were analyzed by two-way ANOVA. Result: The initial mass values were similar for both materials with no significant differences in weight loss after simulate toothbrushing with 20,000 and 50,000 cycles (p > 0.05). The resin modified glass ionomer cement showed more surface roughness. The initial value (1.37 ± 0.24 µm) has increased significantly (p < 0.001) after 20,000 (2.98 ± 1.38 µm) and 50,000 cycles of brushing (3.43 ± 2.29 µm), but no statistical differences were noticed between the cycles. Conclusion: The different cycles of brushing did not result on material weight loss, but there was increased surface roughness on modified resin glass ionomer cements.

Ação de Escovas Dentais de Diferentes Texturas em Cimentos de ionômero de Vidro Indicados para o Tratamento Restaurador Atraumático / Action of Toothbrushes of Different Textures on Glass Ionomer Cements Indicated for Atraumatic Restorative Treatment

Objetivo: Avaliar a ação de escovas dentais macias e médias em cimentos de ionômero de vidro, analisando os parâmetros alteração de massa e rugosidade superficial. Método: Foram testados dois cimentos de ionômero de vidro de alta viscosidade (Ketac tm Molar Easymix/3M Espe e Vitro Molar/DFL), um convencional (Bioglass R/Biodinâmica) e uma resina composta microhíbrida (Z100 tm/3M Espe). Vinte corpos-de-prova de cada material foram submetidos à escovação simulada com creme dental diluído em água destilada (1:2), divididos em grupos de 10 para cada tipo de escova. Os valores de massa foram obtidos após pesagens consecutivas e estabilização do peso. A rugosidade superficial (Ra) foi determinada pela média aritmética de cinco leituras nas superfícies dos corpos-de-prova. Após registro dos valores iniciais de massa e rugosidade, os corpos-de-prova foram submetidos a 20.000 ciclos de escovação simulada e os valores finais de massa e rugosidade foram verificados. Os dados foram avaliados estatisticamente pelos testes t de Student e Anova com pós-teste de Tukey (p<0,05). Resultados: A escovação determinou desgaste em todos os materiais, sendo o menor valor verificado na resina composta Z100 tm, seguido pelos cimentos de ionômero de vidro Ketactm Molar Easymix, Vitro Molar e Bioglass R. O cimento de ionômero de vidro de alta viscosidade com menor valor de rugosidade superficial inicial e final foi o Ketac tm Molar Easymix, com valor médio de 0,50 μ m, sendo estatisticamente diferente dos outros cimentos de ionômero de vidro. Conclusão: As escovas dentais macias e médias causaram desgastes semelhantes.

Objective: To evaluate the action of soft- and middle-bristle toothbrushes on glass ionomer cements indicated for atraumatic restorative treatment by analyzing the parameters mass change and surface roughness. Method: One conventional (Bioglass R/Biodinâmica) and two high-viscosity (Ketac tm Molar Easymix/3M ESPE and Vitro Molar/DFL) glass ionomer cements and a microhybrid composite resin (Z100 tm/3M ESPE) were tested. Twenty specimens of each material were subjected to simulated toothbrushing with dentifrice diluted with distilled water (1:2), divided in groups of 10 specimens for each type of toothbrush. The mass values were obtained after consecutive recordings and weigh stabilization. Surface roughness (Ra) was determined by the arithmetic mean of five readings on specimen surface. After recording the initial mass and surface roughness values, the specimens were subjected to 20,000 cycles of simulated toothbrushing, and the final mass and surface roughness values were recorded. Data were analyzed statistically by the Student’s t-test and ANOVA with Tukey’s post-test (p<0.05). Results: Toothbrushing produced wear of all materials; Z100 tm composite resin exhibited the highest value, followed by Ketac tm Molar Easymix, Vitro Molar® and Bioglass R glass ionomer cements. Ketac™ Molar Easymix was the high-viscosity glass ionomer cement with lower initial and final surface roughness (Ra= 0.50 μm) and differed significantly from the other glass ionomer cements. Conclusion: Soft- and medium-bristle toothbrushes caused similar wear on the materials.

Efeito da própolis no crescimento in vitro de microrganismos associados à periodontite em pacientes HIV-positivo / Effect of propolis on in vitro growth of microrganisms associated with periodontitis in HIV positive patients

A própolis tem demonstrado ser um bom antimicrobiano frente a diferentes microrganismos. O objetivo deste estudo foi avaliar in vitro a eficácia da própolis no controle de microrganismos que podem estar associados à periodontite em pacientes HIV-positivo. Para isto, foram utilizadas soluções de própolis marrom aquosa e alcoólica a 12%, própolis verde alcoólica a 12% e controle positivo com clorexidina 0,12%. Avaliaram-se o halo de inibição e as unidades formadoras de colônia eliminadas na presença da própolis que demonstrou resultados estatisticamente semelhantes à clorexidina sobre os microrganismos testados, sendo que a própolis verde apresentou ação antimicrobianas maior que a própolis marrom. A própolis apresentou poder antimicrobiano sobre P. aeruginosa e S.aureus semelhantes à clorexidina (p>0,05). Em relação a C. albicans, o poder antifúngico da própolis, apesar de inferior ao da clorexidina, não deve ser desconsiderado. Os dados obtidos indicam que a própolis pode ser usada como coadjuvante no controle do biofilme dental em pacientes HIV-positivo, evitando os efeitos adversos da clorexidina.

It has been demonstrated that propolis is a good antibiotic against different microorganisms. The purpose of this study was to evaluate in vitro the efficiency of propolis against microorganisms that can be related to periodontitis in HIV-positive patients. 12% alcoholic and aqueous brown propolis solutions, 12% alcoholic green propolis solution and 0.12% chlorhexidine were used. The halos of microbial growth inhibition and CFU eliminated in contact with propolis were determined. The results demonstrated differences not statistically significant between propolis and the clorhexidine on the microorganisms tested. Green propolis was more effective than brown propolis. Propolis, showed an antimicrobial effect against P. aeruginosa and S. aureus similar to clorhexidine (p>0,05). In relation to C. albicans, the antifungal effect, although inferior to clorhexidine, should not disregarded. The data obtained suggest that propolis may be used as a good substitute for chlorhexidine without its adverse effects in controlling microorganisms from HIV positive patients.