Análise de lesões orofaciais registradas no Instituto Médico-Legal de São Luís (MA), no período de 2011-2013 / Analysis of orofacial injuries recorded in the Forensic Medicine Institute of São Luís (MA), from 2011 to 2013

Introdução: Os traumas são causas comuns de morbidades e mortalidade da população mundial. Um dos mais prevalentes é o bucomaxilofacial, pois a face é uma região muito exposta e pouco protegida.Traumas faciais podem resultar em lesões de tecidos moles e fraturas ósseas, causando graves complicações e até danos irreversíveis, e seu autor deve ser enquadrado corretamente segundo a legislação brasileira. Objetivo: Analisar o perfil das vítimas, as causas, as características das lesões orofaciais, bem como o profissional responsável pela perícia e a classificação da lesão de acordo com o artigo 129 do Código Penal Brasileiro. Método: Foram analisados laudos emitidos por médicos e odontolegistas do Instituto Médico Legal da cidade de São Luís (MA), no ano de 2011 à 2013 de vítimas acometidas por lesões orofaciais. Resultados: Os resultados demonstraram que o sexo masculino foi omais atingido (55,4%), a faixa etária mais envolvida foi 20-29 anos (40,3%), a etiologia principal foi agressão física (73,4%), a lesão mais frequente foi escoriação (25,3%) e a região mais acometida da facefoi a orbitária (26%). O profissional que mais emitiu laudos foi o médico-legista (90,8%). Das lesõesorofaciais qualificadas (39,8%), 23,0% resultaram em debilidade da função mastigatória, 4,5% emdebilidade da função mastigatória e estética e 22,3% em deformidade permanente. Conclusão: Conclui-seque é grande o número de lesões orofaciais registradas no IML de São Luís e que essas lesões foram avaliadas mais criteriosamente pelo odontolegista, ressaltando-se, com isso, a fundamental atuação desse profissional nas perícias dessa natureza.

Introduction: Traumas are common causes of morbidities and mortality in world's population. Maxillofacialtrauma is one of the most prevalent, because face is very exposed and unprotected. Facial trauma canresult in soft tissue injuries and bone fractures, causing serious complications and even permanen tdamages, making necessary the appropriate legal framework of attackers. Objective: To analyze theprofile of the victims, reason and the characteristics of orofacial lesions recorded in Forensic MedicineInstitute data, São Luís (MA), Brazil, between years of 2011 to 2013, as well as the professional responsible for expertise (doctors and dentists) and classifications in accordance with Article 129 of theBrazilian Penal Code. Methods: It were analyzed reports issued by doctors and dentistry in the period of2011 to 2013, for affected patients with orofacial injuries. Results: Results showed that male sex was themost affected (55,4%), age most involved was 20-29 years (40,3%), the main etiology was physicalaggression (73,4%), the most common injury was abrasion (25,3%) and the region most affected was theorbital (24,9%). The professional that issued more reports was the coroner (90,8%). Between the qualifiedorofacial lesions (39,8%), 23,0% resulted in weakness of masticatory function, 4,5% in weakness ofmasticatory function and aesthetics and 22,3% in permanent deformity. Conclusion: It was concluded that the number of orofacial injuries registered in the IML of São Luís data was great and these lesions wereevaluated more critically by forensics dentists, requiring their presence of this professional.

Association between early childhood caries and maternal caries status: A cross-section study in São Luís, Maranhão, Brazil.

OBJECTIVE: This study aims to evaluate the association between early childhood caries (ECC) and maternal caries status, and the maternal perception of ECC risk factors. MATERIALS AND METHODS: A cross-sectional study was carried out with 77 mother-child pairs, the children ranging from 12 to 36 months of age and their mothers, who were seeking dental care at a health center in São Luís, Maranhão, Brazil. Data collection was conducted using a specific questionnaire for mothers. Oral clinical examination of the mother-child binomial to assess caries incidence, gingival bleeding (GB) and visible plaque was done. Home visits were performed in 10% of the sample in order to observe the environmental conditions, dietary habits and dental hygiene practices. RESULTS: The findings showed that the caries prevalence in children was 22.5 times higher in the mother who had decayed tooth (prevalence ratio [PR] = 22.5, confidence interval [CI] 95% = 3.2-156.6, P < 0.001). GB also was observed in 14 mothers and children, the PR in pair was 12.2 (CI95% = 1.6-88.9, P < 0.001). The variables are related for the mother-child binomial in regression linear analysis. CONCLUSION: The maternal caries status was associated with ECC.

Socioeconomic, nutritional and behavioral factors associated with severe childhood caries in children aged 18-36 months

Objective:To relate the occurrence of severe childhood caries with nutritional, socioeconomic and behavioral factors among preschool children. Material and Methods:This cross-sectional study included 111 children aged 18-36 months who sought dental care in basic health units of São Luis, Brazil. The oral health status was measured by the DMFT index (number of decayed, missing and filled teeth), IPV/ISG. Socioeconomic, nutritional and behavioral data were collected through a questionnaire applied to parents. Caries Group was defined as DMFT ≥ 1. Data were analyzed using the Chi-square test and Fisher exact test. Poisson regression models and incidence rate ratio (IRR)were used for multivariate analysis, adopting significance level of 5% and confidence interval (CI) of 95%. Results:It was observed that 61 children (55%) were free from caries and 50 (45%) had the disease. In the Caries Group, 38 (76%) had white spot lesions, 70% had the habit of consuming sweets between meals (p=0.04) and the sucrose intake frequency was considered high (3x daily). After multivariate analysis, age (IRR=1.05, 95%CI=1.03 to 1.07, p <0.001) and consumption of sweets (IRR=1.46, 95%CI=1.11 to 1.92 p=0.006) were associated with increased incidence of caries. Conclusion:The findings of this study suggest that frequent exposure to sugars in the form of sweets between meals, lack of guidance of mothers on oral hygiene and increased age were determining factors for the occurrence of severe childhood caries

Effect of substrate and adhesive system type on composite resin restorations

Introduction: Although it is possible to obtain a reliable bond between enamel and composite resin, the ideal bonding method of composite resin to dentin still needs to be developed. Variables such as the type of adhesive system used and type of dentin substrate can influence on the adhesion. Objective: The purpose of this study was to compare the shear bond strength of composite resin restorations to human and bovine dentin using three adhesive systems. Material and methods: Fifteen human third molars sectioned into two halves and 30 bovine incisors were cut into blocks (4x4mm), embedded in acrylic resin and ground flat to expose the dentin. The specimens were randomly divided into six groups (n = 10): group 1 - human dentin using Scotchbond Multi-Purpose; group 2 - human dentin using Adper Single Bond 2; group 3 - human dentin using Adper Prompt L-Pop; group 4 - bovine dentin using Scotchbond Multi-Purpose; group 5 - bovine dentin using Adper Single Bond 2; group 6 - bovine dentin using Adper Prompt L-Pop. After composite resin restoration procedure, the specimens were stored into distilled water for 24h at 37ºC and then submitted to the shear test using a universal testing machine. The failure patterns were examined microscopically and classified as adhesive, cohesive in resin, cohesive in dentin or both, and mixed. The ANOVA (two-way) and Tukey's post hoc were used. Chi-square test for independence was used for analysis of failure mode. The significance level was set at 5%. Results: A significant difference in shear bond strength was observed among adhesive systems (p = 0.031), with higher values for one-bottle adhesive (8.87±2.72) and lower for self-etching (6.38±3.15), and between the two types of substrate (p = 0.018), with higher values for human dentin. However, there was no significant difference for the adhesive system/substrate interaction (p = 0.11). Adhesive failure was the predominant failure mode for all adhesive systems and for the two substrates. Conclusion: Shear bond strength was different between human and bovine substrates and for the adhesive system used.

Influence of alloy microstructure on the microshear bond strength of basic alloys to a resin luting cement

The aim of this study was to evaluate the influence of microstructure and composition of basic alloys on their microshear bond strength (µSBS) to resin luting cement. The alloys used were: Supreme Cast-V (SC), Tilite Star (TS), Wiron 99 (W9), VeraBond II (VBII), VeraBond (VB), Remanium (RM) and IPS d.SIGN 30 (IPS). Five wax patterns (13mm in diameter and 4mm height) were invested, and cast in a centrifugal casting machine for each basic alloy. The specimens were embedded in resin, polished with a SiC paper and sandblasted. After cleaning the metal surfaces, six tygon tubes (0.5 mm height and 0.75 mm in diameter) were placed on each alloy surface, the resin cement (Panavia F) was inserted, and the excess was removed before light-curing. After storage (24 h/37°C), the specimens were subjected to µSBS testing (0.5 mm/min). The data were subjected to a one-way repeated measures analysis of variance and Turkey's test (α=0.05). After polishing, their microstructures were revealed with specific conditioners. The highest µSBS (mean/standard deviation in MPa) were observed in the alloys with dendritic structure, eutectic formation or precipitation: VB (30.6/1.7), TS (29.8/0.9), SC (30.6/1.7), with the exception of IPS (31.1/0.9) which showed high µSBS but no eutectic formation. The W9 (28.1/1.5), VBII (25.9/2.0) and RM (25.9/0.9) showed the lowest µSBS and no eutectic formation. It seems that alloys with eutectic formation provide the highest µSBS values when bonded to a light-cured resin luting cement.

O objetivo deste estudo foi avaliar a influência da microestrutura e da composição de ligas básicas quanto à resistência de união (RU) a um agente cimentante resinoso. Foram usadas as seguintes ligas: Supreme Cast-V (SC), Tilite Star (TS), Wiron 99 (W9), VeraBond II (VBII), VeraBond (VB), Remanium (RM) and IPS d.SIGN 30 (IPS). Cinco padrões em cera (13 mm de diâmetro e 4 mm de altura) para cada uma das ligas básicas foram incluídos e fundidos em uma máquina de fundição. As amostras foram então embutidas em resina, polidas com lixas e jateadas. Após a limpeza das superfícies, seis cilindros de tygon tube (0,5 mm de altura e 0,75 mm de diâmetro) foram colocados sobre a superficie da liga e preenchida com cimento resinoso (Panavia F), o excesso foi removido antes da fotoativação. Após armazenagem (24 h/37ºC), cada amostra foi ensaiada por microcisalhamento a 0,5 mm/min. Os dados foram tratados por análise de variância para e medidas repetidas e teste Tukey (α=0,05). Para avaliar a microesturutura, as mesmas amostras foram polidas e condicionadas com solução específica. Os valores mais altos da RU (média/desvio padrão em MPa) foram encontrados para as ligas com estrutura dendrítica, formação eutética e precipitados: VB (30,6/1,7), TS (29,8/0,9), SC (30,6/1,7), com exceção da IPS (31,1/0,9) que apresentou alto valor de RU, mas sem formação eutética. As ligas W9 (28,1/1,5), VBII (25,9/2,0) and RM (25,9/0,9) apresentaram os menores valores de RU e ausência de formação eutética. Pode-se inferir que os valores mais elevados de resistência de união ao cimento resinoso fotoativado ocorre com as ligas que apresentam formação de eutético.

Avaliação da resistência à remoção de mini-implantes para ancoragem ortodôntica / Evaluation of resistance to the removal of mini-implants for orthodontic anchorage

Introdução: A movimentação ortodôntica é limitada por forças recíprocas de ação e reação. Tendo em vista esses aspectos, a utilização dos mini-implantes surge como um novo conceito de ancoragem em Ortodontia. Objetivo: Avaliar a resistência à remoção de mini-implantes para ancoragem ortodôntica. Metodologia: Usou-se costela de porco onde foram fixados 20 mini-implantes de titânio da marca SIN de 1,6mm de diâmetro e 8mm de comprimento e seccionados em 20 blocos (osso/mini-implante) de 6X10 mm e inseridos em tubos de PVC de 10X16 mm e divididos em dois grupos (n=10), grupo I: autoperfurantes; grupo II: autorrosqueantes. Foi avaliada a força de remoção (Tira Test 2420). Resultado: Os resultados em Newton (N) foram analisados estatisticamente pelo teste de Fisher, com significância de 5%. A força média para remoção de todos os mini-implantes foi de 87,0 N ± 26,6, sendo para os autoperfurantes de 92,4 N ± 33,0 e 82,2 N ± 19,6 para os autorrosqueantes. O teste de Fischer mostrou não haver diferença estatisticamente significante entre os grupos (p=0.575). Conclusão: Os mini-implantes analisados apresentam resistência à tração suficientemente superior àquela necessária para as aplicações clínicas; Não houve diferença significante entre os dois tipos de mini-implantes analisados.

Introduction: Orthodontic movement is limited by reciprocal forces of action and reaction. In view of this, the use of mini-implants has emerged as a new concept in orthodontic anchorge. Objective: To evaluate resistance to the removal of mini-implants for orthodontic anchorage. Methods: We used pork ribs onto which 20 titanium mini-implants titanium of the SIN brand, 1.6 mm in diameter and 8 mm in length, were fixed, sectioned into 20 blocks (bone/mini-implant), 6x10 mm, and inserted into PVC tubes, 10x16 mm, and divided into two groups (n= 10) as follows: group I: self-perforating screws; group II: self-threaded screws. An evaluation was made of the removal force (Strip Test 2420) Result: The results obtained in Newton (N) were statistically analyzed by Fisher's test with a significance of 5%. The mean force found for removal of all the mini-implants evaluated was 87.0 N ± 26.6, being 92.4 N ± 33.0 for the self-perforating screws and 82.2 N ± 19.6 for the self-threaded ones. Fischer's test showed no statistically significant differences between the groups (p=0.575). Conclusion: The mini-implants analyzed exhibit a resistance to traction higher than that required for clinical applications; there were no significant differences between the two types of mini-implants analyzed.

Efeito da clorexidina a 2% no mecanismo de adesão do cimento de ionômero de vidro: resistência ao cisalhamento / Chlorhexidine's effect at 2% in the mechanism of adhesion of glass ionomer: shear bond strength

Objetivo: O objetivo deste estudo foi verificar a influência da clorexidina gel a 2% na resistência de união ao cisalhamento do cimento de ionômero de vidro (CIV). Material e Métodos: Foram confeccionados 45 blocos de 10x10mm de dentes bovinos, incluídos em resina acrílica, lixados até obter uma superfície plana em dentina e divididos em 3 grupos (n=15): I - Controle: superfície limpa com spray, seca e restaurada com CIV-Vitro Molar; II - superfície limpa com spray, seca, seguida de aplicação de clorexidina gel a 2%, deixada em repouso por 2 minutos, limpa com "bola" de algodão e restaurada; III - lavagem, aplicação de clorexidina gel a 2%, deixada em repouso por 2 minutos, limpeza com spray, seca e restaurada. Os corpos de prova foram submetidos ao teste de cisalhamento em uma máquina TIRATest 2420. Resultados: Os resultados foram avaliados pelo teste Kruskal-Wallis (p<0,05). Verificou-se diferença significante em função do tratamento aplicado p=0,049. Conclusão: A aplicação da clorexidina por 2 minutos e lavagem posterior comportou-se semelhante ao grupo-controle.

Objective: The goal of this study was to investigate the interference of chlorhexidine gel at 2% by shear tests the adhesion of Glass Ionomer Cement. Material and Methods: The 45 bovine teeth were used and made of blocks of 10x10 mm, including acrylic resin and polished until a flat dentin surface. Then randomly divided into 3 groups (n = 15): I - Control: the surface was cleaned with spray (water/air), dried and restored with glass ionomer Vitro Molar (DFL) II - the surface washed with spray (water/air), dried, followed by the application of chlorhexidine gel at 2%, left to stand for 2 minutes, cleaned with a "ball" of cotton and restored; III - the washing was done with an application of chlorhexidine gel at 2%, left rest to for 2 minutes, then cleaned with spray (water/air), dried and restored. The specimens were subjected to shear stress by the machine TIRATest 2420. Results: The results were analyzed by Kruskal-Wallis (p < 0,05). From the graphical analysis, we found the shear stresses with p = 0,049. It showed a significant difference between the tensions according the treatment applied. Conclusion: The application of chlorhexidine for 2 minutes and posterior rinsing behaved similar to the control group.

Evaluation of shear bond strength of orthodontic resin and resin modified glass ionomer cement on bonding of metal and ceramic brackets

Objective:The aim of this study was to evaluate the shear bond strength of orthodontic resin and resin-modified glass ionomer cement on bonding of metal and ceramic brackets. Material and methods: Forty bovine teeth were sectioned and embedded into PVC with chemically-cured acrylic resin. The labial surfaces were flattened and received prophylaxis with pumice and water. Then they were divided into four groups, according to the bonding material and the type of bracket. Group 1: metallic bracket + Transbond XT; Group 2: metallic bracket + Vitremer; Group 3: ceramic bracket + Transbond XT; Group 4: ceramic bracket + Vitremer. The bonding was performed according to the manufacturers’ recommendations. The shear bond strength test was conducted in a universal testing machine (TIRAtest 2420) at a crosshead speed of 0.5 mm/min. Then, the fractured surfaces were evaluated using a stereomicroscope (x15 magnification) to check the adhesive remnant index. Data was subjected to two-way ANOVA and Tukey’s test for pairwise comparisons (a = 0.05).Results: The results suggested a non-significant effect of the interaction (p > 0.97), and only main factors were significant (p = 0.0001). The bond strength of Transbond XT was statistically higher than Vitremer. Ceramic brackets obtained the highest values of resistance when compared with metal brackets. Conclusion: The ceramic brackets bonded with Transbond XT orthodontic resin have excellent bond strength results.

Characterization of two Ni-Cr dental alloys and the influence of casting mode on mechanical properties.

PURPOSE: The aim of this study was to evaluate the tensile strength, elongation, microhardness (MHV), composition and microstructure of two Ni-Cr based alloy, cast under different casting conditions. METHODS: Before casting, the alloy ingots were evaluated as regards composition (EDX) and microstructure (Optical microscopy, SEM and EDX). The casting conditions were as follows: electromagnetic induction in an environment controlled with argon (EWA), electromagnetic induction in an environment under vacuum (EWV), electromagnetic induction without atmosphere control (EWNC) and blowtorch (BT). For each condition, 16 specimens were obtained, each measuring 25 mm high and 2.5mm in diameter. The ultimate tensile strength (UTS) and elongation (EL) tests were performed in a Kratos machine (1.0mm/min). Fractured specimens were embedded in bakelite resin and polished for Vickers Microhardness analysis (1000 g/10s) with 4 penetrations in each specimen. The UTS, EL and MHV results were evaluated for two-way ANOVA and Tukey's test (α=0.05). RESULTS: The cross-product interaction was statistically significant for all properties evaluated (p<0.0001), lower UTS, VHN and high elongation means were observed for the Ni-Cr-Mo-Be alloy tested when cast under the induction/argon (p<0.05). Higher UTS means were found for Ni-Cr-Mo-Ti alloy tested when cast under the induction/vacuum, and induction/air and flame/air condition (p<0.05). The two alloys show a microstructure with a dendritic formation with the presence of eutectic presence. CONCLUSION: The Ni-Cr-Mo-Ti alloy showed high UTS, MHV and lowest EL comparaded with the tradicional Ni-Cr-Mo-Be, that show lowest UTS, MHV and higher EL when cast on induction/argon.

Influence of alloy microstructure on the microshear bond strength of basic alloys to a resin luting cement.

The aim of this study was to evaluate the influence of microstructure and composition of basic alloys on their microshear bond strength (µSBS) to resin luting cement. The alloys used were: Supreme Cast-V (SC), Tilite Star (TS), Wiron 99 (W9), VeraBond II (VBII), VeraBond (VB), Remanium (RM) and IPS d.SIGN 30 (IPS). Five wax patterns (13 mm in diameter and 4mm height) were invested, and cast in a centrifugal casting machine for each basic alloy. The specimens were embedded in resin, polished with a SiC paper and sandblasted. After cleaning the metal surfaces, six tygon tubes (0.5 mm height and 0.75 mm in diameter) were placed on each alloy surface, the resin cement (Panavia F) was inserted, and the excess was removed before light-curing. After storage (24 h/37°C), the specimens were subjected to µSBS testing (0.5 mm/min). The data were subjected to a one-way repeated measures analysis of variance and Turkey's test (α=0.05). After polishing, their microstructures were revealed with specific conditioners. The highest µSBS (mean/standard deviation in MPa) were observed in the alloys with dendritic structure, eutectic formation or precipitation: VB (30.6/1.7), TS (29.8/0.9), SC (30.6/1.7), with the exception of IPS (31.1/0.9) which showed high µSBS but no eutectic formation. The W9 (28.1/1.5), VBII (25.9/2.0) and RM (25.9/0.9) showed the lowest µSBS and no eutectic formation. It seems that alloys with eutectic formation provide the highest µSBS values when bonded to a light-cured resin luting cement.

Microinfiltração em restaurações classe V: análise da forma geométrica da cavidade e do tipo de adesivo / Microleakage of class V restorations: analyses of the cavity's geometric shape and type of adhesive

Introdução: o desenvolvimento de materiais e técnicas na Odontologia Restauradora tem como finalidade a obtenção de um confiável vedamento marginal, pois a microinfiltração ainda é um dos principais motivos de insucesso das restaurações. Objetivo: analisar "in vitro" o efeito da configuração cavitária e do tipo de sistema adesivo na microinfiltração em restaurações classe V, em esmalte, com resina composta. Material e método: foram selecionados 60 dentes bovinos, confeccionadas 30 cavidades na face vestibular de forma retangular e 30 de forma circular, sendo então divididos aleatoriamente em seis grupos, conforme a forma geométrica e o sistema adesivo utilizado: Magic Bond, Adper Single Bond 2 e Clearfil SE BOND. Os dentes foram restaurados com resina composta Z-350, utilizando um incremento, fotopolimerizado por 40 segundos, e feito o acabamento/polimento com disco Sof-Lex. Posteriormente, os dentes foram armazenados em água destilada à temperatura ambiente por sete dias e impermeabilizados com esmalte cosmético, deixando uma margem de 1 mm ao redor da restauração. Foram imersos, então, em solução aquosa de nitrato de prata a 50% por um período de duas horas no escuro, lavados com água corrente, colocados em solução reveladora por seis horas, lavados, seccionados no centro da restauração e as fatias foram analisadas na lupa estereoscópica de 25× de aumento. Os dados foram submetidos à análise estatística não paramétrica de Kruskal-Wallis (p < 0,05). Resultado: não houve diferença estatisticamente significante para ambos os fatores analisados (p = 0,233 e p = 0,158). Conclusão: a forma da cavidade não influenciou na microinfiltração; todos os adesivos comportaram-se de maneiras semelhantes quanto à microinfiltração.

Introduction: the development of materials and techniques in restorative dentistry aims to achieve a good marginal sealing because microleakage is still one of the main reasons for failure of restorations. Objective: To analyze "in vitro" the effect of cavity configuration and the type of adhesive system on microleakage of class V resin composite, in enamel. Material and method: 60 bovine teeth were selected, and 60 cavities were prepared on the buccal surface, 30 rectangular and 30 rounded shaped. They were randomly divided in 6 groups according to the geometric form and the bonding system used: Magic Bond, Adper Single Bond 2 and Clearfil SE BOND. The teeth were restored with Z-350 composite resin, using one increment, lightcured for 40 seconds and polished with a Sof-Lex disc. After that the teeth were stored in distilled water at room temperature for seven days and further sealed with nail varnish, leaving a 1 mm window around the restoration margin. They were then immersed in 50% aqueous silver nitrate solution for 2 hours in the dark, rinsed under tap water, placed in revealing solution for 6 hours under fluorescent light, washed, sectioned in the center of the restoration and the slices were viewed under stereoscopic glasses at 25× magnification. The data were submitted to Kruskal-Wallis non-parametric test (p < 0.05). Result: no statistically significant difference for either factor analyzed (p = 0.233 and p = 0.158) was observed. Conclusion: the cavity shape did not influence in microleakage; all the adhesives behaved in similar manners as to microleakage.

Characterization of aqueous silver nitrate solutions for leakage tests.

OBJECTIVES: To determine the pH over a period of 168 h and the ionic silver content in various concentrations and post-preparation times of aqueous silver nitrate solutions. Also, the possible effects of these factors on microleakage test in adhesive/resin restorations in primary and permanent teeth were evaluated. MATERIAL AND METHODS: A digital pHmeter was used for measuring the pH of the solutions prepared with three types of water (purified, deionized or distilled) and three brands of silver nitrate salt (Merck, Synth or Cennabras) at 0, 1, 2, 24, 48, 72, 96 and 168 h after preparation, and storage in transparent or dark bottles. Ionic silver was assayed according to the post-preparation times (2, 24, 48, 72, 96, 168 h) and concentrations (1, 5, 25, 50%) of solutions by atomic emission spectrometry. For each sample of each condition, three readings were obtained for calculating the mean value. Class V cavities were prepared with enamel margins on primary and permanent teeth and restored with the adhesive systems OptiBond FL or OptiBond SOLO Plus SE and the composite resin Filtek Z-250. After nail polish coverage, the permanent teeth were immersed in 25% or 50% AgNO3 solution and the primary teeth in 5% or 50% AgNO3 solutions for microleakage evaluation. ANOVA and the Tukey's test were used for data analyses (α=5%). RESULTS: The mean pH of the solutions ranged from neutral to alkaline (7.9±2.2 to 11.8±0.9). Mean ionic silver content differed depending on the concentration of the solution (4.75±0.5 to 293±15.3 ppm). In the microleakage test, significant difference was only observed for the adhesive system factor (p=0.000). CONCLUSIONS: Under the tested experimental conditions and based on the obtained results, it may be concluded that the aqueous AgNO3 solutions: have neutral/alkaline pH and service life of up to 168 h; the level of ionic silver is proportional to the concentration of the solution; even at 5% concentration, the solutions were capable of indicating loss of marginal seal in the composite restorations; the 3-step conventional adhesive system had better performance regarding microleakage in enamel on primary and permanent teeth.

Characterization of aqueous silver nitrate solutions for leakage tests

OBJECTIVE: To determine the pH over a period of 168 h and the ionic silver content in various concentrations and post-preparation times of aqueous silver nitrate solutions. Also, the possible effects of these factors on microleakage test in adhesive/resin restorations in primary and permanent teeth were evaluated. MATERIAL AND METHODS: A digital pHmeter was used for measuring the pH of the solutions prepared with three types of water (purified, deionized or distilled) and three brands of silver nitrate salt (Merck, Synth or Cennabras) at 0, 1, 2, 24, 48, 72, 96 and 168 h after preparation, and storage in transparent or dark bottles. Ionic silver was assayed according to the post-preparation times (2, 24, 48, 72, 96, 168 h) and concentrations (1, 5, 25, 50 percent) of solutions by atomic emission spectrometry. For each sample of each condition, three readings were obtained for calculating the mean value. Class V cavities were prepared with enamel margins on primary and permanent teeth and restored with the adhesive systems OptiBond FL or OptiBond SOLO Plus SE and the composite resin Filtek Z-250. After nail polish coverage, the permanent teeth were immersed in 25 percent or 50 percent AgNO3 solution and the primary teeth in 5 percent or 50 percent AgNO3 solutions for microleakage evaluation. ANOVA and the Tukey's test were used for data analyses (α=5 percent). RESULTS: The mean pH of the solutions ranged from neutral to alkaline (7.9±2.2 to 11.8±0.9). Mean ionic silver content differed depending on the concentration of the solution (4.75±0.5 to 293±15.3 ppm). In the microleakage test, significant difference was only observed for the adhesive system factor (p=0.000). CONCLUSIONS: Under the tested experimental conditions and based on the obtained results, it may be concluded that the aqueous AgNO3 solutions: have neutral/alkaline pH and service life of up to 168 h; the level of ionic silver is proportional to the concentration of the solution; even at 5 percent concentration, the solutions were capable of indicating loss of marginal seal in the composite restorations; the 3-step conventional adhesive system had better performance regarding microleakage in enamel on primary and permanent teeth.

Efeito do substrato e do tipo de adesivo dental na microinfiltração em restaurações de resina composta / Effect of substrate and types of dental adhesive on microleakage in composite resin restoration

Foi avaliada in vitro a influência do substrato (bovino e humano) e do sistema adesivo (condicionamentototal e primer autocondidionante) na microinfiltração, em restauração classe II. Em 16 terceiros molares humanos e 16 incisivos bovinos, foram confeccionadas duas cavidades proximais ?Slot? vertical(OM-OD), com margem gengival em dentina. Em seguida, as cavidades foram divididas em 4 grupos(n=16), conforme o adesivo e o substrato: grupo I ? substrato humano/adesivo de condicionamentototal; grupo II ? substrato humano/adesivo de primer autocondicionante; grupo III ? substrato bovino/adesivo de condicionamento total; grupo IV ? substrato bovino/adesivo de primer autocondicionante.As cavidades foram restauradas com composito Tetric Ceram com 3 incrementos. Em seguida, osdentes foram estocados a 37º C por 30 dias. Após, impermeabilizados com esmalte cosmético, foramimersos em solução de nitrato de prata a 50%, por 2 horas, lavados e imersos em solução reveladorapor 6 horas. Depois foram seccionados, e as amostras, analisadas em lupa de 25X. Os dados foram submetidosà análise estatística não paramétrica de Kruscal-Wallis (p<0,05) que revelou existência de diferença significativa entre os adesivos (p=0.000). Quanto ao substrato, não houve diferença significativa(p>0.05). Concluiu-se que os substratos humano e bovino comportaram-se estatisticamente, de forma semelhante; o adesivo de condicionamento total comportou-se estatisticamente de forma significante.

It was evaluated in vitro the substrate influence (bovine and human) and the adhesive system (totaletching and self-etching primer) on microleakage, in class II restoration. In 16 human third molarsand 16 bovine incisors were prepared two proximal cavities vertical "Slot" (OM-DO), with the gingivalmargin in dentin. Then, the cavities were divided into four groups (n = 16) according to the adhesiveand the substrate: group I - human substrate / total etching adhesive, group II - human substrate /self-etching primer adhesive, group III - bovine substrate / total etching adhesive, group IV - bovinesubstrate / self-etching primer adhesive. The cavities were restored with Tetric Ceram composite withthree increments. Then the teeth were stored at 37 º C for 30 days. After that, sealed with cosmetic nailvarnish, immersed in a 50% solution of silver nitrate, for 2 hours, washed and immersed in revealingsolution for 6 hours. After the samples were sectioned and analyzed in a 25X loupe. Data were subjectedto nonparametric statistical analysis of Kruscal-Wallis (p<0.05) revealed the existence of significantdifferences between the adhesives (p=0.000). Regarding to the substrate, there was no significant difference(p>0.05). It was concluded that: the human and bovine substrates behaved statistically in a similar way, the total etching adhesive behaved statistically significant.

Efeito da forma geométrica da cavidade e do tipo de adesivo na microinfiltração em restaurações classe V / Effect of the geometric way of the cavity and the sticker type in the microleakage in restorations classe V

Foi avaliada "in vitro" a influência da forma da cavidade e do tipo de adesivo (frasco único e primer autocondicionante) na microinfiltração, em restaurações classe V. Em 40 incisivos bovinos, foram confeccionadas 40 cavidades com margens em esmalte, sendo 20 retangulares e 20 circulares. Em seguida, foram divididas em 4 grupos (n=10), de acordo com o adesivo e a forma geométrica: grupo 1 - circular/adesivo de frasco único; grupo 2 - retangular/adesivo de frasco único; grupo 3 - retangular/adesivo de primer autocondicionante; grupo 4 - circular/adesivo de primer autocondicionante. As cavidades foram restauradas com resina composta Tetric Ceram®, com incremento único. Em seguida, os dentes foram estocados a 37ºC, por 30 dias, e, em seguida, impermeabilizados com esmalte cosmético e imersos em solução de nitrato de prata a 50% por 2 horas, lavados e imersos em solução reveladora por 6 horas. Após isto, foram seccionados, e as amostras, analisadas em lupa estereoscópica de 25X. Os dados foram submetidos à análise estatística não paramétrica de Kruskal?Wallis (p<0,05) em que se constatou diferença estatisticamente significante entre os grupos estudados. Concluiu-se que o adesivo de frasco único associado à cavidade circular comportou-se estatisticamente significante frente às outras combinações; as cavidades circulares comportaram-se significantes em relação às retangulares.

It was evaluated ?in vitro? the shape of the cavity influence and the type of adhesive (single bottle and self-etching primer) on microleakage, in class V restorations. In 40 bovine incisors were prepared 40 cavities with margins in enamel, 20 rectangular and 20 circular. Then, were divided into four groups (n = 10) according to the adhesive and geometrical form: group 1 - circular / single bottle adhesive, Group 2 - rectangular / single bottle adhesive, Group 3 - rectangular / self-etching primer adhesive, group 4 - circular / self-etching primer adhesive. The cavities were restored with composite resin Tetric Ceram? with only one increment. Then the teeth were stored at 37?C, for 30 days, and then sealed with cosmetic nail varnish and immersed in a 50% solution of silver nitrate for 2 hours, washed and immersed in revealing solution for 6 hours. After that, the samples were sectioned and examined under stereoscopic loupe of 25X. Data were subjected to non-parametric Kruskal-Wallis statistical analysis (p <0.05) which showed statistically significant difference among the groups. It was concluded that: The single-bottle adhesive associated with circular cavity behaved statistically significant according to the other combinations, the circular cavities behaved significant in relation to the rectangular.

Incidência das Posições Anatômicas e Agenesia dos Terceiros Molares em Estudantes de São Luís, Maranhão / Incidence of the Anatomic Positions and Agenesis of Third Molars in Students from São Luís, MA, Brazil

Objeti vo: Investi gar os aspectos clínicos e radiográfi cos dosterceiros molares com relação à incidência das posiçõesanatômicas e agenesia em estudantes de uma escola públicade São Luís, Maranhão.Método: Trata-se de um estudo transversal descriti vo dascaracterísti cas clínicas e radiográfi cas dos terceiros molaresnuma população de estudantes de 18 a 21 anos de ambos osgêneros. Avaliou-se 155 pacientes por meio de exame clínicoe radiográfi co (radiografi a panorâmica dos maxilares) noperíodo de maio a novembro de 2006. Dos 155 estudantes,obti vemos 531 dentes presentes e 89 ausentes. Dos presentes,somente 462 foram avaliados segundo as posições de Wintere Pell e Gregory, visto que apresentavam rizogênese completa.Registraram-se ainda a ausência congênita destes dentes. Todosos dados foram registrados em fi chas apropriadas, tabuladosno EPI-INFO 2000 e submeti dos ao teste Qui-Quadrado paraverifi car a existência de associações entre as variáveis deestudo, com nível de signifi cância de 5%.Resultados: Os resultados mostraram diferenças signifi cantespara as posições mesial (p=0.0001), distal (p=0.0278) e horizontal(p=0.0179) em relação aos diferentes terceiros molares. Já paraa posição verti cal não houve diferenças. (p=0.1354), entretantofoi mais freqüente na amostra. Com relação à classifi cação dePell e Gregory não foram observadas diferenças signifi cantes(p>0.05). A agenesia foi consideravelmente freqüente nestapopulação com 14,4%.Conclusão: As posições mais freqüentes segundo Winter forama verti cal seguida pela mesial, distal e horizontal; e segundo Pelle Gregory foram Classe I, II e III e Posições A, B e C . A agenesiaesteve freqüente na amostra...

Objecti ve: To investi gate the clinical and radiographic aspectsof third molars with respect to the incidence of the anatomicpositi ons and agenesis in students from a public school of SãoLuís, MA, BrazilMethod: This was a descripti ve cross-secti onal study ofthe clinical and radiographic characteristi cs of third molarsin a populati on of students of both genders aged 18 to 21years. A total of 155 pati ents were examined clinically andradiographically (panoramic radiograph of the jaws) betweenMay and November 2006. The 155 students had 531 teethpresent and 89 absent. From the teeth that were present, only462 had complete root formati on and were evaluated accordingto the Winter and Pell & Gregory positi ons. Congenital absenceof teeth was also noted. The data were recorded in appropriatecharts, tabulated in the EPI-INFO 2000 soft ware and analyzedusing the Chi-square test to verify the existence of associati onsbetween the study variables, with level of signifi cance set at5%.Results: The results showed signifi cant diff erences for themesial (p=0.0001), distal (p=0.0278) and horizontal (p=0.0179)positi ons for the diff erent third molars. No signifi cant diff erenceswere found for the verti cal positi on (p=0.1354), but it was themost frequent positi on in the sample. Regarding the Pell &Gregory classifi cati on, no signifi cant diff erences were observed(p>0.05). Agenesis was considerably frequent in this populati on(14.4%).Conclusion: According to Winter, the most frequent positi onswere verti cal followed by mesial, distal and horizontal, whileaccording to Pell & Gregory were Class I, II and III and Positi onsA, B and C. Agenesis was a frequent occurrence in the sample...

Disfunção temporomandibular em indivíduos atendidos no setor de otorrinolaringologia / Temporomandibular disorders in otolaryngology patients

Objetivo: Avaliar a prevalência de disfunção temporomandibular em indivíduos que procuraram o serviço de otorrinolaringologia do Hospital da Universidade Federal do Maranhão. Métodos: Foram avaliados 303 indivíduos do serviço de otorrinolaringologia do Hospital Universitário da Universidade Federal do Maranhão em São Luís durante um período de três meses. Para captação e interpretação dos dados, bem como verificação da disfunção temporomandibular, foi utilizado um questionário auto-aplicado previamente validado. Resultados: Após coleta e interpretação dos dados de 303 indivíduos, os resultados obtidos foram: 61,7% (187 indivíduos) foram considerados como necessitando de tratamento ou avaliação odontológica, dos quais 67,7% eram do sexo feminino. Já 9,9% dos indivíduos não apresentaram sintomas de disfunção temporomandibular. Outros resultados mostraram que 48,51% dos indivíduos apresentaram dor de cabeça; 52,14% dor no pescoço e ombro; 50,49% dor na região do ouvido e 46,20% ruídos articulares. Conclusão: A prevalência de disfunção temporomandibular foi de 61,72%, sendo significativamente maior no gênero feminino (p=0,006); e as prevalências em relação aos índices, foram: disfunção temporomandibular ausente de 9,9%; disfunção temporomandibular leve de 28,4%; disfunção temporomandibular moderada de 36,6% e disfunção temporomandibular severa de 25,1%.

Objective: The objective of this study was to assess the prevalence of temporomandibular disorders in individuals who visit the otolaryngology service of the Federal University of Maranhão hospital. Methods: A total of 303 patients of the otolaryngology service of the abovementioned university hospital located in São Luiz were assessed over three months. A previously validated self-administered questionnaire was used to collect and interpret data and to verify temporomandibular disorders. Results: The results of the data collected from 303 individuals and the respective interpretation were: 61.7% (187 individuals) were in need of an otolaryngological assessment or treatment. Of these, 67.7% were females. Only 9.9% of the individuals did not present symptoms of temporomandibular disorders. Other results show that 48.51% of the individuals had headaches, 52.14% had neck and shoulder pain, 50.49% had pain in the ear area and 46.20% had joint noise. Conclusion: The prevalence of temporomandibular disorders was 61.72% and significantly higher among females (p=0.006). Temporomandibular disorders were absent in 9.9%; mild in 28.4%; moderate in 36.6% and severe in 25.1% of the sample.

Efeito da clorexidina na adesão do cimento de ionômero de vidro utilizado em restaurações atraumáticas através de teste de microinfiltração / Effect of chlorhexidine on the adhesion of glass ionomer cement used in atraumatic restorative treatments through microleakage test

Objetivo: Avaliar por meio de teste de microinfiltração in vitro, a interferência do "tratamento" da cavidade com clorexidina gel a 2% na adesão do ionômero de vidro indicado para tratamento restaurador atraumático. Métodos: Foram utilizados 60 dentes bovinos, nos quais foram confeccionadas cavidades classe V na face vestibular. Os dentes foram divididos em três grupos (n=20), aleatoriamente e restaurados conforme a distribuição dos grupos: Grupo 1, controle; Grupo 2, aplicação da clorexidina seguida de lavagem e restauração com o ionômero; Grupo 3, aplicação da clorexidina seguida de secagem com algodão e restauração com o ionômero. Confeccionadas as restaurações, os dentes foram estocados em uma estufa umidificadora a 37ºC por 30 dias. Em seguida, impermeabilizados com esmalte cosmético, imersos em solução de nitrato de prata a 50% por 2 horas, lavados e, por fim, imersos em solução reveladora por 6 horas. Logo após, foram lavados e submetidos a 1 corte no sentido mésio-distal no meio da restauração, obtendo-se 120 amostras, que foram analisadas em Lupa Estereoscópica (25X) por três examinadores, segundo os escores de 0 a 4. Resultados: Os resultados obtidos foram tabulados e submetidos à análise estatística não-paramétrica de Kruskal-Wallis, constatando-se que houve diferença significativa entre os grupos estudados (p<0,05). Conclusão: O uso da clorexidina aplicada sob o ionômero de vidro, sem lavagem da cavidade, apresentou infiltração significativa; a aplicação da clorexidina por 2 minutos com lavagem posterior da cavidade comportou-se semelhante ao grupo controle; independente do grupo estudado, nenhum conseguiu evitar a microinfiltração.

Objective: The objective of this study was to assess in vitro how 2% chlorhexidine gel affects the adhesion of the glass ionomer indicated for atraumatic restorative treatments. The assessment was based on the microleakage test. Methods: A total of 60 bovine incisive teeth were used, where sixty Class V cavities were prepared in the middle of the buccal surface. These teeth were randomly divided into 3 groups (n=20 each), and restored as follows: Group 1: control; Group 2: chlorhexidine administration followed by rinsing and restoration with the ionomer; Group 3: chlorhexidine administration followed by drying with cotton and restoration with the ionomer. Once the restorative procedures were done, the teeth were stored in a humidified holding cabinet at 37ºC for 30 days. After that, the teeth were waterproofed with nail polish and immersed in a 50% silver nitrate solution for 2 hours, rinsed, and finally immersed in a developing solution for 6 hours. They were then rinsed, cut horizontally in the middle of the restoration and the resulting 120 samples were analyzed with a stereo microscope with a magnification of 25X by three examiners, who gave the specimens scores from 0 to 4. Results: The data were statistically analyzed by the non-parametric Kruskal-Wallis test. Significant differences were found among the studied groups (p<0.05). Conclusion: When chlorhexidine is administered under the ionomer glass and the cavity is not rinsed, significant infiltration occurs. When chlorhexidine is administered for 2 minutes with subsequent rinsing of the cavity, the result is similar to that to the control group. Nevertheless, microleakage occurred in all groups.

Influence of human and bovine substrate on the microleakage of two adhesive systems

The aim of this study was to evaluate in vitro the marginal sealing of two adhesive systems and to analyze the influence of human and bovine substrates on marginal microleakage in enamel. Rectangular-shaped class V cavities (4 mm wide x 2 mm high x 2 mm deep) were made as follows: 8 cavities were prepared on the buccal and lingual surfaces of the human teeth with margins located on enamel and 16 cavities were prepared on the buccal surfaces of the bovine teeth. The cavities were randomly assigned to 4 groups of 8 cavities according to the adhesive system and substrate: G1 - Prime & Bond 2.1 (Dentsply)/human substrate; G2 - Adhese (Ivoclar/Vivadent)/human substrate; G3 - Prime & Bond 2.1 (Dentsply)/bovine substrate; G4 - Adhese (Ivoclar/Vivadent)/bovine substrate. The cavities were filled with microhybrid composite resin (Fillmagic) and after polishing/finishing procedures, the teeth were subjected to a thermocycling regimen of 500 cycles with 1-min immersions in water at 55° ±2°C and 5° ± 2°C. Next, the teeth were coated with two layers of nail polish to within 1 mm of the margin, submerged in a 50 percent silver nitrate solution for 2 h, rinsed thoroughly in running tap and immersed in developing solution for 8 h. The restorations were bisected resulting in 16 specimens. Microleakage was observed under a stereomicroscope at x25 and recorded using four-point (0-3) scoring system. The data were analyzed statistically by the Mann Whitney U-test at 5 percent significance level. Leakage was present in all specimens and there was statistically significant difference between the adhesive systems. Adhese self-etching system showed significantly more leakage in both substrates (human - p= 0.0001 and bovine - p= 0.0031). There was no statistically significant difference between human and bovine substrates for either of the adhesive systems based on different bonding mechanisms (Prime & Bond 2.1 - p= 0.6923 and Adhese - p= 0.6109). Neither of the...

Influence of human and bovine substrate on the microleakage of two adhesive systems.

The aim of this study was to evaluate in vitro the marginal sealing of two adhesive systems and to analyze the influence of human and bovine substrates on marginal microleakage in enamel. Rectangular-shaped class V cavities (4 mm wide x 2 mm high x 2 mm deep) were made as follows: 8 cavities were prepared on the buccal and lingual surfaces of the human teeth with margins located on enamel and 16 cavities were prepared on the buccal surfaces of the bovine teeth. The cavities were randomly assigned to 4 groups of 8 cavities according to the adhesive system and substrate: G1--Prime & Bond 2.1 (Dentsply)/human substrate; G2--Adhese (Ivoclar/Vivadent)/human substrate; G3--Prime & Bond 2.1 (Dentsply)/bovine substrate; G4--Adhese (Ivoclar/Vivadent)/bovine substrate. The cavities were filled with microhybrid composite resin (Fillmagic) and after polishing/finishing procedures, the teeth were subjected to a thermocycling regimen of 500 cycles with 1-min immersions in water at 55 degrees+/-2 degrees C and 5 degrees+/-2 degrees C. Next, the teeth were coated with two layers of nail polish to within 1 mm of the margin, submerged in a 50% silver nitrate solution for 2 h, rinsed thoroughly in running tap and immersed in developing solution for 8 h. The restorations were bisected resulting in 16 specimens. Microleakage was observed under a stereomicroscope at x25 and recorded using four-point (0-3) scoring system. The data were analyzed statistically by the Mann Whitney U-test at 5% significance level. Leakage was present in all specimens and there was statistically significant difference between the adhesive systems. Adhese self-etching system showed significantly more leakage in both substrates (human--p= 0.0001 and bovine--p=0.0031). There was no statistically significant difference between human and bovine substrates for either of the adhesive systems based on different bonding mechanisms (Prime & Bond 2.1--p= 0.6923 and Adhese--p= 0.6109). Neither of the adhesive systems was capable to completely prevent microleakage and the self-etching system was more susceptible to microleakage.