Shear Bond Strength of Orthodontic Brackets Fixed with Remineralizing Adhesive Systems after Simulating One Year of Orthodontic Treatment

The objective of this study is to assess, in vitro, the shear bond strength of orthodontic brackets fixed with remineralizing adhesive systems submitted to thermomechanical cycling, simulating one year of orthodontic treatment. Sixty-four bovine incisor teeth were randomly divided into 4 experimental groups (n=16): XT: Transbond XT, QC: Quick Cure, OL: Ortholite Color, and SEP: Transbond Plus Self-Etching Primer. The samples were submitted to thermomechanical cycling simulating one year of orthodontic treatment. Shear bond strength tests were carried out using a universal testing machine with a load cell of 50 KgF at 0.5 mm/minute. The samples were examined with a stereomicroscope and a scanning electron microscope (SEM) in order to analyze enamel surface and Adhesive Remnant Index (ARI). Kruskal-Wallis and Mann-Whitney (with Bonferroni correction) tests showed a significant difference between the studied groups (p<0.05). Groups XT, QC, and SEP presented the highest values of adhesive resistance and no statistical differences were found between them. The highest frequency of failures between enamel and adhesive was observed in groups XT, QC, and OL. Quick Cure (QC) remineralizing adhesive system presented average adhesive resistance values similar to conventional (XT) and self-etching (SEP) adhesives, while remineralizing system (OL) provided the lowest values of adhesive resistance

Assessment of the aesthetic impact and quality of life of home dental bleaching in adult patients

This study aimed to evaluate the impact of home bleaching with 10% carbamide peroxide on the quality of life and aesthetic perception of patients. A total of 107 patients between 18 and 38 years of age with good oral and general health and at least on

Repair of Iatrogenic Furcal Perforation with Mineral Trioxide Aggregate: A Seven-Year Follow-up

Teeth with furcal perforation present difficult resolution and dubious prognosis. Several materials have been proposed and calcium silicate-based cements such as mineral trioxide aggregate (MTA) are the most recommended. However, its long-term clinical behavior still remains poorly understood. The present study reports a clinical case of furcal perforation repair using Angelus MTA, with a 7-year follow-up. Patient sought treatment 2 months after iatrogenic accident. First lower right molar presented clinical signs such as fistula and bone loss between mesial and distal roots. Firstly, all root canals were treated and then furcal perforation was sealed with MTA Angelus and the dental crown was restored with composite resin. Radiographic evaluation was immediately performed to analyze the furcal perforation filling. After 7 years, a new clinical and imaging evaluation using periapical radiography and cone-beam computed tomography (CBCT) showed absence of clinical signs and symptoms, and alveolar bone reconstitution with periodontal space reduction. Angelus MTA presented good clinical behavior in the iatrogenic furcal perforation resolution based on long-term clinical evidence.Keywords: Endodontics; Furcation Perforation; Mineral Trioxide Aggregate; Root Canal Treatment; Root Perforation; Tooth Perforation

Bond strength and internal adaptation of customized glass fiber posts using different bulk-fill flow resins

This study aimed to evaluate the bond strength and internal adaptation of customized glass fiber posts using Bulk Fill flowable composite resins (BF) and conventional composite resin. Fifty bovine teeth were randomly divided (n=10) according to the fol

In-office dental bleaching in adolescents using 6% hydrogen peroxide with different application tips: randomized clinical trial

Despite the availability of in-office bleaching gels with a 6% concentration of hydrogen peroxide (HP), these gels have not been evaluated in younger patients. They are commercially available with a tip, associated or not with a brush, where the tip with a brush spreads the gel over the entire surface to have a smaller thickness (thin layer) since the manufacturers indicate the application of a thin layer of gel. Objective: This randomized, split-mouth, double-blind clinical trial evaluated the efficacy of in-office bleaching with 6% HP in adolescents using different application tips, as well tooth sensitivity (TS) and aesthetic self-perception. Methodology: Sixty participants were randomized for 6% HP self-mixing bleaching gel tip design: without brush and with brush. In-office bleaching was performed in 3 sessions of 50 minutes. Color change was evaluated using a digital spectrophotometer (ΔE ab , ΔE 00 , and ΔWI D ) and color guide (ΔSGU), the absolute risk and intensity of TS with a visual analogue scale and aesthetic self-perception with the oral aesthetic scale (a=0.05). Results: The groups achieved similar bleaching regardless of the application tip (p&gt;0.05). However, only for ΔWI D , a significant mean difference (MD) was observed in the third week (MD 2.3; 95% CI 1.2 to 3.3; p &lt; 0.001) and at one month (MD 1.6; 95% CI 0.6 to 2.6; p &lt; 0.03) favoring the tip without brush. Regarding TS, 45% in the tip-without-brush group and 33% in the tip-with-brush group reported TS (odds ratio 0.61; 95% CI 0.29 to 1.28; p&lt;0.02), with low TS intensity (MD 0.05; 95% CI -0.06 to 0.17; p&gt;0.36). All patients reported improved aesthetic self-perception after bleaching (MD -1.3; 95% -1.8 to -0.9; p&lt;0.001). Conclusions: Regardless of the tip used bleaching with 6% HP achieved a bleaching efficacy and improved the aesthetic self-perception. However, a lower risk of TS for application using the tip with brush was observed. &nbsp

Endodontic Management of Open Apex Teeth Using Lyophilized Collagen Sponge and MTA Cement: Report of Two Cases

Teeth with open apices, such as in immature teeth or those with apical root resorption are clinical cases with difficult immediate resolution. With the use of mineral trioxide aggregate (MTA) in dentistry, it was possible to optimize the treatment time of these cases by immediate placement of apical plug and the root canal filling. However, some negative effects can occur if MTA is extruded beyond the apex. To avoid this accident, it has been recommended to use of an apical matrix prior to placement of MTA. This study reports two clinical cases of apical plug placement in teeth with pulp necrosis and open apices. One case had an immature apex due to dental trauma and the other case had apical resorption due to the presence of endodontic infection in the root canal. MTA apical plug with approximately 4 mm thickness, was placed in the apical zone of the root and immediately the canal was obturated with gutta-percha and endodontic sealer. Follow-up evaluations showed clinical and radiographic evidence of success.Keywords: Apex; Collagen; Endodontics; Mineral Trioxide Aggregat

Análise da capacidade de vedamento bacteriano na interface entre implante e pilar em dois sistemas de junção / Analysis of bacterial sealing capacity at the interface between implants and abutments in two joining systems

Avaliar in vitro a contaminação bacteriana na interface implante-pilar em implantes dentários com conexões dos tipos hexágono interno e hexágono externo, por meio de análise microbiológica. Foram analisados 24 conjuntos (n = 12), os quais foram divididos nos seguintes grupos: conexão hexágono interno (HI); conexão hexágono externo (HE); controle positivo (CP) e controle negativo (CN). Todos os grupos foram contaminados no interior do implante com Escherichia coli, exceto o grupo CN. Em seguida, os pilares foram conectados, aplicado torque de 20 N e os conjuntos foram imersos em uma solução de caldo Brain Heart Infusion (BHI), onde foram mantidos durante 14 dias. Os conjuntos foram desconectados por contra torque e porções do caldo de cultura foram coletadas e plaqueadas em Ágar BHI por 24 horas, para observar a formação das unidades formadoras de colônias (CFUs). Depois, foi realizada a coleta de uma porção das CFUs para esfregaço e coloração de Gram. Após os 14 dias, houve turbidez do meio e presença de depósitos em 6/11 tubos de ensaio do hexágono interno e 5/11 para hexágono externo, não havendo diferença estatística (p &gt; 0,05) entre os grupos. Foi confirmado o crescimento dos bacilos Gram-negativos, onde foi possível visualizar a presença de Escherichia coli nas placas correspondentes aos tubos de ensaio que apresentaram turbidez anteriormente. Os resultados do presente estudo sugerem que o tipo de implante não beneficia a redução da contaminação bacteriana através da conexão implante-pilar

Enceramento diagnóstico: previsibilidade no tratamento estético indireto

O enceramento diagnóstico é uma ferramenta de grande importância dentro da filosofia atual de excelência estética no tratamento restaurador indireto. Trata-se da reprodução em cera realizada a partir de um modelo de estudo e tem como finalidade observar, em três dimensões, a futura forma final dos dentes, ajudar visualmente na realização do preparo dentário e demonstrar ao paciente o resultado final do tratamento antes mesmo de iniciá-lo, obtendo-se, assim, máxima previsibilidade. O objetivo desse artigo é mostrar, através de casos clínicos, a previsibilidade no tratamento restaurador indireto obtida por meio do enceramento diagnóstico

The Effect of Power Bleaching Actived by Several Light Sources on Enamel Microhardness

The purpose of this study was to evaluate the influence of different light sources for in-office bleaching on surface microhardness of human enamel. One hundred and five blocks of third molars were distributed among seven groups. The facial enamel surface of each block was polished and baseline Knoop microhardness of enamel was assessed with a load of 25 g for 5 s. Subsequently, the enamel was treated with 35% hydrogen peroxide bleaching agent and photo-activated with halogen light (group A) during 38 s, LED (group B) during 360 s, and high intensity diode laser (group C) during 4 s. The groups D (38 s), E (360 s), and F (4 s) were treated with the bleaching agent without photo-activated. The control (group G) was only kept in saliva without any treatment. Microhardness was reassessed after 1 day of the bleaching treatment, and after 7 and 21 days storage in artificial saliva. The mean percentage and standard deviation of microhardness in Knoop Hardness Number were: A 97.8 +/- 13.1 KHN; B 95.5 +/- 12.7 KHN; C 84.2 +/- 13.6 KHN; D 128.6 +/- 20.5 KHN; E 133.9 +/- 14.2 KHN; F 123.9 +/- 14.2 KHN; G 129.8 +/- 18.8 KHN. Statistical analysis (p < 0.05; Tukey test) showed that microhardness percentage values were significantly lower in the groups irradiated with light when compared with the non-irradiated groups. Furthermore, the non-irradiated groups showed that saliva was able to enhance the microhardness during the measurement times. The enamel microhardness was decreased when light sources were used during the bleaching process and the artificial saliva was able to increase microhardness when no light was used