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The purpose of this review is to provide the readers with current information and state-of-the-art of digital scanning systems within the orthodontics. Introducing the commercially available intraoral and facial scanning systems, as well as bringing future perspectives to these systems. The emergence of digital scanners associated with computer-aided design is one of today’s key diagnostic tool enhancements in orthodontics. Among the main applications in orthodontics, it is the analysis for diagnosis, treatment planning, and prediction of the final result. There is a range of possibilities for the application of digital scanners in orthodontics, both facial and intraoral, bringing benefits to the correct choice of a treatment technique and a shorter time period to acquire the patient documentation and case planning. The intraoral scanning allowed for a broader diagnosis, more precise, and efficient planning with esthetic treatments. However, there are still some drawbacks such as the tip size of the scanners, which makes difficult to read the maxillary tuberosity region. Other drawbacks are related to the limit of patient’s mouth opening, humidity control (i.e., saliva), and light reflection during scanning by mini-implants and bars. Facial digital scanning has also an important applicability in cases of orthodontic treatment associated with orthognathic surgery, when the acquired files are combined with cone-beam computed tomography information. Although facial scanners are of great interest for facial analysis studies, they are still costly or, in the case of the new more affordable and portable devices, they still have accuracy limitations.

Made available in DSpace on 2019-10-06T15:43:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01 This study aimed to investigate the olfactory fossa according to the Keros classification using cone beam computed tomography. This cross-sectional study analysed cone beam computed tomography images selected from a database belonging to a radiology centre. The scans of 174 healthy patients were analysed by using the Xoran software. Gender, age, and side were correlated with the Keros classification. The mean age of the 174 patients was 45.3 years. The most prevalent Keros classification was type II (65.52%), followed by type III (20.69%) and type I (13.79%). No significant differences were found between Keros classification and the variables age, right side (p value = 0.4620), and left side (p value = 0.5709). There were also no significant differences between gender and the variables right side (p value = 0.1421) and left side (p value = 0.2136). Based on these results, we suggest that cone beam computed tomography can be recommended for analysis of the anterior skull base. Keros type II was the most prevalent type in our sample. Postgraduate Program in Dentistry Cruzeiro do Sul University (UNICSUL) Department of Diagnosis and Surgery São José dos Campos Dental School São Paulo State University (UNESP) Department of Orthodontics and Radiology University of São Paulo City (UNICID) Department of Diagnosis and Surgery São José dos Campos Dental School São Paulo State University (UNESP)

Purpose This study evaluated dentoalveolar skeletal changes promoted by the Forsus appliance, associated to fixed orthodontic appliance, in the correction of Class II, division 1 malocclusion, from Computed Tomography (CT). Methods sample consisted of 10 youngsters (7 males and 3 females), with a mean age of 13.86 years. Two Forsus® models were installed after the alignment and leveling phase of the teeth. Two tomographic images of each patient, T1 and T2 (initial and immediately after removal of Forsus® appliance) were done to perform the anatomical tracings and obtain the variables of interest. The data were described by means and standard deviations. For the comparison between the initial and final phases, the paired “t” test was used and a significance level of 5% was considered (p Results small skeletal changes were observed, such as posterior maxillary displacement and a slight mandibular growth. Larger dentoalveolar changes occurred as extrusion, retrusion and lingualization of upper incisors; Intrusion, protrusion and vestibularization of the lower incisors; Mesialization and extrusion of lower molars. Conclusion Considering the patients evaluated in this study, Forsus® presented similar results to other mandibular propulsion appliances, with dentoalveolar effects that favored Class II correction, however, with very slight skeletal modifications.

This study was undertaken to assess in vivo the corrosion in two commercial nickel-titanium (NiTi) orthodontic archwires removed from the oral cavity of patients using fluoride mouthwashes. Five volunteers took part in this study on the corrosion behavior of two brands of NiTi archwires (3M and AO (brand of archwire)) during use of two mouthwashes with neutral sodium fluoride 1.1%, one with acidulated fluoride 1.1%, and one with placebo and a control group. Each patient used one mouthwash in three different periods of time for 1 min a day for 30 days. The archwires were assessed with scanning electron microscopy and atomic force microscopy for qualitative and quantitative analysis. The values obtained with atomic force microscopy (AFM) were submitted to normality test, two-way analysis of variance, and Tukey's test at a significance level of 5%. The AFM images showed a gradual qualitative increase in the roughness of both types of wire between the treatments: control

Background The more accurate the adjustments built into the brackets, the less the need of additional bends in orthodontic archwires during treatment. Methods The aim of this study was to investigate the torque value accuracy of Roth prescription brackets from several commercially available brands. A total of 360 upper and lower incisor brackets from six different commercial brands (i.e. 3M Abzil, KiriumLine; Dentsply GAC, Ovation; Morelli, Roth Light; Ormco, Synthesis; Rocky Mountain Orthodontics, Integra; and 3M Unitek, Miniature Twin) were selected and divided into 18 experimental groups (N.=20). Results The brackets were submitted to SEM examination to acquire clear photomicrographs of all edges. The angles formed by the slot's walls and bracket's base were measured to calculate the torque values. The measured torque values were submitted to Student's t-test or Mann-Whitney test (global α=0.05) for comparing the experimental groups to Roth prescription values, depending on the bracket indication: +12°, +8° or -1°. A tolerance of ±1° (ISO 27020:2010) was considered. Only experimental groups using upper central incisor brackets from Rocky Mountain Orthodontics (P=0.037) and 3M Unitek (P=0.001) were statistically different compared to the Roth prescription ones (+12°). However, all the groups presented great variability (standard deviation) regarding the same brand and indication, showing that there is no accuracy in the fabrication process. Conclusions It is evident that the manufacturing methods of orthodontic brackets need to reach higher degrees of precision and homogeneity.

In order to improve the adhesion between cement and zirconia, aluminum oxide sandblasting (JAT) and Rocatec, sandblasting with silica coated aluminum oxide (ROC), also the primer Signum Zirconia Bond (SZB) were used. The objective of the study was to verify the influence of the surface treatment and the presence of SZB primer in relation to the bond strength between cement and zirconia, using 60 zirconia specimens measuring 7 mm in length, 7 mm in width and 3 mm in length. thickness. Three surface treatments were evaluated: sandblasting with pre-sintering aluminum oxide (OPre), Rocatec Soft before (RPre) and zirconia final sintering (RPos), and also, regarding the presence or not of SZB. All specimens were cemented with Panavia F. The bond strength (RU) was evaluated through a shear test with a standardization device from SDI (Southern Dental Industrie) on a universal testing machine (Kratos), with a speed of 0 , 5 mm / min. The data were evaluated using Kruskal-Wallis / Mann-Whitney (α = 0.05). Average (SD) of UK without the use of SZB: OPre: 5.5 (0.9) Ba; RPre: 4.0 (1.4) Bb; RPos: 5.0 (0.5) Bab. Average (SD) of UK using SZB: OPre: 7.9 (1.5) Aab; RPre: 6.7 (2.3) Ab; RPos: 9.0 (1.2) Aa. The use of primer increased the cement / zirconia bond strength regardless of the surface treatment performed, in addition, the Rocatec group after sintering with primer, obtained higher bond strength values ​​compared to the other study groups. Para mejorar la adhesión entre el cemento y el zirconio, fue utilizado el chorro con oxido de aluminio (JAT) y el Rocatec, chorro con oxido de aluminio revestido por sílica (ROC).también el primer Signum Zirconia Bond (SZB). El objetivo de este estudio fue verificar la influencia del tratamiento de superficie y de la presencia del primer SZB en relación a la resistencia de unión entre el cemento y el zirconio, utilizando 60 cuerpos de prueba en zirconio midiendo 7mm de altura,7mm de ancho y 3 mm de espesor. Fueron evaluados tres tratamientos de superficie : chorro con oxido de aluminio pre-sinterizado (OPre),Rocatec Soft antes (RPre)y después de la sinterización final del zirconio (RPos) y también cuando hay presencia o no del SZB. Todos los cuerpos de prueba fueron cementados con Panavia F. La resistencia de unión (RU) fue evaluada por el teste de cizallamiento con el dispositivo de padronización de la SDI (Southern Dental Industrie) en una maquina de ensayo universal (Kratos), a una velocidad de 0,5 mm/min. Los datos fueron evaluados utilizando Kruskal-Wallis/Mann-Whitney (α=0,05). Medias (DP) de RU sin utilización del SZB: OPre: 5,5 (0,9) Ba; RPre: 4,0 (1,4) Bb; RPos: 5,0 (0,5) Bab. Medias (DP) de RU con la utilización de SZB: OPre: 7,9 (1,5) Aab; RPre: 6,7 (2,3) Ab; RPos:9,0 (1,2) Aa. El uso del primer aumento la resistencia de unión cemento/zirconio independientemente del tratamiento de superficie realizado, además, el grupo tratado con Rocatec pos-sinterización con primer obtuvo mayores valores de resistencia de unión comparados a los demás grupos de estudio. Para melhorar a adesão entre cimento e zircônia, foram utilizados jateamento com óxido de alumínio (JAT) e o Rocatec, jateamento com óxido de alumínio revestido por sílica (ROC), também o primer Signum Zircônia Bond (SZB). O objetivo do estudo foi verificar a influência do tratamento de superfície e da presença de primer SZB em relação a resistência de união entre cimento e zircônia, utilizando 60 corpos de prova de zircônia medindo 7 mm de comprimento, 7 mm de largura e 3 mm de espessura. Foram avaliados três tratamentos de superfície: jateamento com óxido de alumínio pré-sinterização (OPre), Rocatec Soft antes (RPre) e após-sinterização final da zircônia (RPos), e também, quanto a presença ou não de SZB. Todos os corpos de prova foram cimentados com Panavia F. A resitência de união (RU) foi avaliada através de teste de cisalhamento com dispositivo de padronização da SDI (Southern Dental Industrie) em uma máquina de ensaios universal (Kratos), com velocidade de 0,5 mm/min. Os dados foram avaliados utilizando Kruskal-Wallis/Mann-Whitney (α=0,05). Médias (DP) de RU sem a utilização de SZB: OPre: 5,5 (0,9) Ba; RPre: 4,0 (1,4) Bb; RPos: 5,0 (0,5) Bab. Médias (DP) de RU com a utilização de SZB: OPre: 7,9 (1,5) Aab; RPre: 6,7 (2,3) Ab; RPos:9,0 (1,2) Aa. A utilização do primer aumentou a resistência de união cimento/zircônia independentemente do tratamento de superfície realizado, além disso, o grupo Rocatec pós-sinterização com primer, obteve maiores valores de resistência de união comparados aos demais grupos do estudo.

Objective The present study aimed to evaluate the precision of the torque applied by 0.022" self-ligating brackets of different brands, the precision of parallelism between the inner walls of their slots, and precision of their slot height. Eighty brackets for upper central incisors of eight trademarked models were selected: Abzil, GAC, American Orthodontics, Morelli, Orthometric, Ormco, Forestadent, and Ortho Organizers. Images of the brackets were obtained using a scanning electron microscope (SEM) and these were measured using the AutoCAD 2011 software. The tolerance parameters stated in the ISO 27020 standard were used as references. The results showed that only the Orthometric, Morelli, and Ormco groups showed results inconsistent with the ISO standard. Regarding the parallelism of the internal walls of the slots, most of the models studied had results in line with the ISO prescription, except the Morelli group. In assessing bracket slot height, only the Forestadent, GAC, American Orthodontics, and Ormco groups presented results in accordance with the ISO standard. The GAC, Forestadent, and American Orthodontics groups did not differ in relation to the three factors of the ISO 27020 standard. Great variability of results is observed in relation to all the variables.

Purpose To evaluate the effect of Nd:YAG laser irradiation and erosive challenge on bond strength of two adhesive systems to dentin. Methods Twenty bovine incisors were cut and grounded to obtain eighty slabs of flat dentin. Specimens were allocated into eight groups, based on: adhesive system—a two-step etch-and-rinse and a two-step self-etch; laser irradiation—Nd:YAG (1 W/10 Hz) or control (no laser irradiation); and erosive challenge after restorative procedure—presence or absence of erosive challenge. Nd:YAG laser groups were submitted to laser irradiation before the restorative procedure. Blocks of composite resin were built up on the bonded surfaces with a Southern Dental Industries device to perform shear bond strength (SBS) test. After, each specimen of erosive challenge, groups were subjected to immersion in Sprite Zero® (20 ml/2 h/24 °C/under agitation). The SBS test (0.5 mm/min) was performed after 24 h of water storage at 37 °C. Failure mode was evaluated with a stereomicroscope (X400). Data were analyzed with three-way ANOVA and Tukey’s post hoc tests (α=0.05). Results The etch-and-rinse adhesive system presented higher bond strength values than self-etch adhesive. Laser irradiation increased the bond strengths values when erosive challenge was present. The predominant failure mode observed was adhesive. Conclusions The irradiation of Nd:YAG laser positively influences the bond strength values when erosive challenges are present. Moreover, the etch-and-rinse adhesive system is a better option to be used in dentin in this clinical condition.

Corrosão é um processo natural que ocorre quando um metal entra em contato com soluções ácidas. Esse fenômeno provoca danos estruturais aos fios ortodônticos de ligas de NiTi e Aço inoxidável.Trinta amostras com 10mm de comprimento, obtidas de arcos superiores de NiTi superelástico e de arcos de Aço, embebidos em ácido cítrico industrializado, solução de sprite e à base de cola. Cada grupo de solução foram embebidas, por 90 minutos, 05 unidades de segmentos de fio de cada liga, por 21 dias consecutivos, compondo 6 grupos experimentais. Após esse procedimento, analisou as amostras por microscopia eletrônica de varredura (MEV).

This pediatric study aimed to assess the masticatory function of patients with anterior open bite through a method that utilizes colorimetric capsules. The sample consisted of 106 patients aged 7-11 years, of whom 51 presented with anterior open bite (experimental group) and 55 presented with normal overbite (control group). The colorimetric capsules used in this evaluation contained basic fuchsin granules, which were used to produce a solution after they were ground during chewing. Each patient was asked to chew 1 capsule for 20 seconds. The absorbance of the obtained solutions was analyzed with a spectrophotometer. Greater masticatory efficiency is directly related to the greater light absorbance of a solution, since light absorbance increases with solution concentration. A nonparametric Wilcoxon test indicated that the solutions obtained from the control group presented significantly greater light absorbance than did those from the experimental group (P0.05). Therefore, children with an anterior open bite exhibited less masticatory efficiency than those with a normal overbite.

Made available in DSpace on 2019-10-06T15:28:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-06-01 Objective: The aim of this study was to investigate the effect of enhancement filters on magnetic resonance imaging (MRI) of the temporomandibular joint (TMJ). Study Design: In total, 66 MRI scans of the TMJ were analyzed without filtration and with the application of 2 filters: Sharpen 1 and Sharpen 2 (OnDemand software). Two dentomaxillofacial radiologists examined the original and filtered images individually. Intra- and interobserver concordance was measured by using generalized estimating equations. The observers evaluated the subjective image quality and the visibility of 3 components of the TMJ: disk, condyle, and articular eminence. The images were ranked on a 4-point scale, from poor to excellent. The image quality of all filtered images was compared by using the χ 2 test and Bonferroni correction for multiple comparisons. Results: Intra- and interobserver concordance was good. The images filtered with Sharpen 1 and Sharpen 2 provided better definition of the structures compared with nonfiltered images, providing the highest scores for subjective image quality for all structures (P < .0001). Conclusions: The use of enhancement filters led to improved subjective quality and may improve the diagnostic efficacy of MRI in TMJ evaluation. Department of Orthodontics and Radiology University of São Paulo City (UNICID) Department of Diagnosis and Surgery São José dos Campos Dental School São Paulo State University (UNESP) School of Medicine University of Cuenca Department of Diagnosis and Surgery São José dos Campos Dental School São Paulo State University (UNESP)

Background Clinical cases involving agenesis of all four maxillary incisors are rare, with no previous reports in the literature. Case report The present case report describes an orthodontic treatment combined with esthetic dentistry in a 10-year-old girl with agenesis of all four permanent maxillary incisors, anterior crossbite, permanence of deciduous maxillary canines and transmigration of permanent maxillary canines into the region of the maxillary central incisors. For this case, it was decided on space closure using a fixed orthodontic apparatus and reshaping of the first premolars transforming them into canines. Porcelain veneers were used on the permanent and deciduous canines, substituting the maxillary central and lateral incisors, respectively. Regarding outcome, there was an improvement in facial profile, correction of the anterior crossbite, satisfactory intercuspidation of the teeth and significant esthetic improvement in smile. Maintaining the patient´s natural dentition also kept the bone plate intact for future placement of implants to substitute maxillary deciduous canines at the appropriate age. Conclusions Interdisciplinary planning combining orthodontics and esthetic dentistry was key in resolving this case. Key words:Tooth agenesis, upper incisors, orthodontic treatment.

The present study aimed to evaluate the precision of the torque applied by 0.022" self-ligating brackets of different brands, the precision of parallelism between the inner walls of their slots, and precision of their slot height. Eighty brackets for upper central incisors of eight trademarked models were selected: Abzil, GAC, American Orthodontics, Morelli, Orthometric, Ormco, Forestadent, and Ortho Organizers. Images of the brackets were obtained using a scanning electron microscope (SEM) and these were measured using the AutoCAD 2011 software. The tolerance parameters stated in the ISO 27020 standard were used as references. The results showed that only the Orthometric, Morelli, and Ormco groups showed results inconsistent with the ISO standard. Regarding the parallelism of the internal walls of the slots, most of the models studied had results in line with the ISO prescription, except the Morelli group. In assessing bracket slot height, only the Forestadent, GAC, American Orthodontics, and Ormco groups presented results in accordance with the ISO standard. The GAC, Forestadent, and American Orthodontics groups did not differ in relation to the three factors of the ISO 27020 standard. Great variability of results is observed in relation to all the variables.

Objetivo: Determinar o pH crítico para ocorrer a corrosão de arcos NiTi em soluções de flúor a 1,1%, variando o pH de 3,5 a 7,0. Materiais e Métodos: Doze amostras com 10mm de comprimento de fio superelástico NiTi 0017 x 0025 (Abzil), obtidas do segmento distal dos arcos. As amostras foram aleatoriamente separadas e imersas dentro de recipientes contendo 40ml de seis soluções (água, soluções fluoretadas com pH: 3,5; 4,0; 4,5; 5,0; 5,5; 6,0; 6,5 e 7,0), sob uma mesa agitadora durante 90 minutos. Todas as amostras foram, então, levadas ao MEV. As imagens das amostras imersas em água e soluções fluoretadas com pH 7,0, 6,5 e 6,0 não se apresentaram diferentes, no entanto a partir da solução fluoretada com pH 5,5, as imagens superficiais apresentaram características diferentes dos grupos anteriores. Conclusão: Com base nos resultados obtidos neste estudo, o pH crítico para corrosão de arcos NiTi em soluções de flúor a 1,1% parece estar entre 6,0 e 5,5.

Objectives To assess whether pastes containing casein phosphopeptide–amorphous calcium phosphate (CPP–ACP) and calcium sodium phosphosilicate (CSP) control artificial caries lesion progression. Methods Enamel slabs of bovine teeth were embedded in polyester resin and had their enamel surfaces serially polished, and tested for surface microhardness (SMH, 25 g, 5 s). Incipient caries-like lesions were pre-formed and specimens were evaluated by microhardness test (SMH post-lesion ) and randomly assigned to five treatment groups ( n = 15): (1) regular dentifrice (RE, 1,100 ppm F); (2) dentifrice with calcium sodium phosphosilicate (CSP); (3) amorphous calcium phosphate stabilized by casein phosphopeptide (CPP–ACP); (4) CPP–ACP with 900 ppm F (CPP–ACP + F) and (5) control group—unexposed to any remineralizing agent. Treatments were applied five times, after the de-remineralization period in the cariogenic challenges. Post-treatments SMH measurements were conducted (SMH post-treatment ). Results ANOVA was applied for data evaluation and revealed a significant difference among the treatments ( p = 0.0161). Tukey's test was conducted and the percentage of mineral loss was calculated. Specimens exposed to CSP (7.1%), RE (6.7%) and CPP–ACP + F (3.8%) showed lower mineral loss than those that in the control group (−11.0%). CPP–ACP group (3.2%) differed from the control, CSP and RE groups. Conclusions Depending on the agent used, a remineralizing effect may be expected, which reflects in caries lesions progression.

OBJETIVOS:1a etapa: validar teste de cisalhamento utilizando um novo dispositivo de padronização através da comparação dos valores de resistência de união (RU) entre a zircônia com dois tratamentos de superfície e um cimento resinoso, aos resultados obtidos com testes de cisalhamento convencional e microcisalhamento; 2a etapa: avaliar o efeito dos primers metálicos à base de MDP por meio da RU entre zircônia Y-TZP e diferentes tipos de cimentos resinosos (de ativação química, duais e auto-adesivo); 3a etapa: avaliar o efeito de dois lasers Nd:YAG e Er:YAG e do jateamento com óxido de alumínio (JAT) na superfície da zircônia Y-TZP antes da sua sinterização final e da abrasão triboquímica mais silano (controle positivo) após a sinterização final, por meio da resistência à flexão (RF), rugosidade superficial (RS) e RU; 4a etapa: avaliar a estabilidade da união entre a zircônia e um cimento resinoso com um primer à base de MDP e de um laser de alta potência após a termociclagem. Os tratamentos superficiais utilizados nesta etapa foram escolhidos com base nos resultados da 2a e 3a etapas. MATERIAL E MÉTODOS: para os testes de RU foram confeccionados corpos de prova de Y-TZP com dimensões 6x6x3mm, e para o teste de RF 2,5x4,5x20 mm. Para 1a etapa os tratamentos de superfície foram JAT+Signum Ziconia Bond (SZB Heraeus), abrasão triboquímica foi realizada Rocatec (ROC 3M Espe), o silano utilizado foi RelyX Ceramic Primer (3M Espe) e os cimentos resinosos: Panavia F (Kuraray), NX3 (Kerr), seT (SDI), Multilink (Ivoclair). Durante a 3a etapa a abrasão triboquímica foi realizada ROC, o laser Nd:YAG (Power Laser ST6, Lares Research - 1,2W, 10 Hz) e Er:YAG (Kavo Key II, KaVo Co. - 120 mJ, 6 Hz). O teste de cisalhamento com dispositivo de padronização foi o método de avaliação da RU utilizado para as 2a, 3a e 4a etapas. Os dados dos testes de RU, RG foram analisados pela ANOVA e Tukey (=0,05) e RF por Kruskall-Wallis (=0,05). RESULTADOS: 1a etapa: pelo teste de microcisalhamento os materiais se comportaram da seguinte forma: JAT+SZB>ROC>CO, sendo que para os outros dois testes de cisalhamento o seguinte ranqueamente foi obtido: JAT+SZB=ROC>CO. 2a etapa: o SZB apresentou maiores valores de RU para todos os cimentos quando comparados aos grupos controle. O ZP aumento os valores para o cimento Panavia F e NX3. Já o AP aumentou os valores para o cimento seT. 3a etapa: para o teste de RU o JAT e Er:YAG resultaram em valores similares ao ROC, sendo que Nd:YAG resultou em maiores valores comparado ao ROC. Quando avaliados por RS: Nd:YAG>Er:YAG>JAT>ROC; já para RF: ROC>JAT=Nd:YAG= Er:YAG. 4a etapa: Após o teste de cisalhamento os seguinte ranqueamento foi obtido: Nd:YAG 24h>Nd:YAG termociclado=SZB 24h>SZB termociclado. CONCLUSÕES: Uma vez que o teste de cisalhamento com dispositivo de padronização mostrou resultados similares ao teste de cisalhamento convencional pode ser um método viável para avaliação da RU. O tratamento com Nd:YAG antes da sinterização final se mostrou efetivo nos valores de RU. OBJECTIVES: first stage: validate shear test using a new device for standardized by comparing the values of bond strength (BS) with conventional shear test and microshear test, between zirconia and a resin cement with two surface treatments. Second stage: evaluate the effect of metal primers based on MDP by BS between YTZP and different types of resin cements. Third stage: evaluate Y-TZP surface treatments effect of two lasers (Nd:YAG and Er:YAG) and two sandblasting procedures, with Al2O3 (JAT) before final sintering and tribochemical slicatization after the final sintering, through the flexural resistance (FR) surface roughness (SR) and BS. Fourth stage: evaluate the bonding stability between zirconia and resin cement using a MDP-based primer or a high power laser, after thermal cycling. MATERIAL AND METHODS: BS Y-TZP specimens were prepared with dimensions of 6x6x3mm, and for FS test with 2,5x4,5x20 mm. In the first stage the surface treatments of the specimens were JAT+ Signum Ziconia Bond (SZB - Heraeus), tibochemical silicatization using Rocatec (ROC - 3MEspe) and control (CO - without treatment). In the second stage the primers used were Alloy-Primer (AP - Kuraray), SZB, Z-Prime Plus (ZP - Bisco), and the resin cements: Panavia F (Kuraray), NX3 (Kerr), set (SDI), Multilink (Ivoclair). During the third stage the tribochemical silicatization was perfomed using ROC. The shear bond strength device standardized was used to evaluate the BS of second, third and fourth stage. Test data for BS, SR were analyzed by ANOVA and Tukey test ( = 0.05) and FS by Kruskall-Wallis test ( = 0.05). RESULTS: first Stage: the microshear test groups behave as follow: JAT+SZB> ROC>CO, and for the other two shear tests following the ranking were obtained: JAT+SZB=ROC>CO. Second stage: the SZB showed higher BS for all cements when compared to control groups. The ZP values increased for Panavia F and NX3. AP values increased only for the seT cement. Third stage: BS values for JAT and Er:YAG were similar to ROC, and Nd:YAG was higher compared to the ROC. When evaluated by SR: Nd:YAG> Er:YAG>JAT> ROC, while for FS: ROC> JAT = Nd:YAG = Er:YAG. Fourth stage: after the shear test the following ranking was obtained: Nd:YAG 24h> Nd:YAG thermocycled = SZB 24h> SZB thermocycled. CONCLUSIONS: shear bond strength test with standardized device showed similar result to the conventional shear bond strength, and it can be considered a viable method for evaluating the BS. Treatment with Nd:YAG before the final sintering was effective in BS.

This in vitro investigation assessed whether different dentifrices would be capable of controlling the enamel erosion progression caused by HCl.Sixty bovine enamel slabs were covered with acid-resistant varnish, except for a 2.5-mm2 circular area on the labial surface. According to a complete block design, the experimental units were immersed in HCl solution (pH 1.2; 0.1M). After storage in artificial saliva for 1 h, specimens (n = 15) were exposed to different dentifrices: Sensodyne Cool Gel (1100 ppm F), Sensodyne ProNamel (1450 ppm F), and PrevDent 5000 (5000 ppm F). The control group was immersed in deionised water. Following five cycles of erosive challenge, the slabs were prepared for porosity evaluation using solutions of copper sulfate and rubeanic acid.ANOVA demonstrated no difference in the enamel porosity as a function of the dentifrice employed (P = 0.5494).The damage caused by a simulated intrinsic erosive challenge seems unable to be controlled by fluoridated dentifrices, even when this ion is found in elevated concentrations.

Quando os túbulos dentinários ficam expostos ao meio bucal, sendo a erosão o principal fator etiológico, estímulos aplicados na dentina provocam movimentação rápida do fluido desencadeando a hipersensibilidade dentinária. O objetivo desse estudo foi avaliar, através modelo crossover 2x2 in situ, se o efeito da irradiação a laser seria capaz de controlar a permeabilidade da dentina radicular erodida submetida a subseqüentes desafios erosivos. Fragmentos de dentina (3x3 mm) foram ciclado por desafio erosivo (ácido cítrico 0.3%, 2h) para induzir lesões erosivas, seguido por um período de remineralização em saliva artificial (24 h). Os espécimes foram irradiados com laser de Nd:YAG (1W/15Hz) ou Er:YAG (100mJ/3Hz) ou não irradiado. Doze voluntários participaram utilizando dispositivos intra-oral, em duas fases de 5 dias cada. No primeiro período, metade dos voluntários expôs os espécimes a episódios erosivos, enquanto a outra metade não expôs a nenhum tipo de desafio. Seguido de um período de 2 dias de washout, os voluntários submeteram os espécimes ao procedimento alternado. No final de cada fase, os espécimes foram removidos e preparados para avaliação da permeabilidade. Após a coloração com soluções de sulfato de cobre e ácido rubêanico, os espécimes foram seccionados e digitalizados sob microscopia óptica A permeabilidade relativa foi quantificada através da relação entre a profundidade de penetração de íons cobre e a espessura da dentina. ANOVA e o teste de Tukey demonstraram que o grupo não irradiado exposto a desafios subseqüentes produziu os maiores valores de permeabilidade (Er:YAG: 4,2%a; Nd:YAG: 4,6%a; Ct: 14,6%b). Os resultados obtidos mostraram que os lasers podem controlar a progressão da erosão na dentina radicular. When the dentinal tubules are exposed to the oral environment, the erosion the main etiological factor, stimuli applied to the dentin causing rapid movement of the fluid causing the hypersensitive dentin. The aim of this investigation was to evaluate, through a crossover 2x2 in situ trial, whether the effect of laser irradiation would be capable to control the permeability of eroded root dentin subjected to further acid challenges. Dentin slabs (3x3 mm) were cycled through erosive challenges (0.3% citric acid 2h) to induce erosion-like lesions, followed by a remineralizing period in artificial saliva (24 h). Specimens were laser-irradiated with Nd:YAG (1W/15Hz) or Er:YAG (100mJ/3Hz) or nonirradiated. Twelve volunteers participated using intraoral devices, in two phases of 5 days each. In the first period, half of participants exposed the specimens to erosive episode, while the other half did not perform any erosive challenge. Followed a 2-day washout period, volunteers submitted the slabs to the alternative procedure. In the end of each phase, specimens were prepared for permeability evaluation. After staining with solutions of copper sulfate and rubianic acid, the specimens were sectioned and scanned under light microscopy. Relative permeability was quantified by the relationship between the depth of penetration of copper ions and the thickness of dentin. ANOVA and Tukey´s test demonstrated that the nonirradiated group exposed to further erosion episodes produced the highest permeability (Er:YAG: 4,2%a; Nd:YAG: 4,6%a; Ct: 14,6%b). The obtained results showed that lasers can control the erosion progression in root dentin.