Pentaerythritol Tetrasalicylate in the Chemical Composition of Root Canal Sealers

Abstract The aim of this study was to synthesize and evaluate physicochemical properties of a new salicylate derivative in experimental calcium-based root canal sealers. Two salicylate derivatives were synthesized for the transesterification reaction of methyl salicylate with two different alcohols (1,3-butylenoglicol disalicylate-BD and pentaerythritol tetrasalicylate -PT) in molar ratio 1:3 and 1:6, respectively. The products (BD and PT), were characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Nuclear Magnetic Resonance spectroscopy (RMN). Calcium-based experimental sealers were prepared with the same catalyst paste (60% of MTA, 39% of n-ethyl-o-toluenesulfonamide, and 1% titanium dioxide) and four different concentrations of BD and PT in the base pastes (40/0 - control, 35/5, 30/10 and 20/20) with 60% of bismuth oxide. The experimental sealers were evaluated for setting time, solubility (24 h, 7, 14 and 30 days), diametral tensile strength and Young's Modulus. Data were analyzed by one- or two-way ANOVA with Tukey's test (p<0.05). The addition of PT reduced the materials setting time. After 24 h the sealer 40/0 and 35/5 had higher solubility, and after 14 and 28 days the sealer 20/20 showed the lowest solubility (p<0.05). After 7 days the sealer 20/20 stabilized its solubility. The sealer 40/0 presented the highest values and the 20/20 presented the lowest values of diametral tensile strength and Young's modulus (p<0.05). The addition of PT to calcium-based root canal sealers provides benefits to the setting time and solubility.

Resumo O objetivo neste estudo foi sintetizar e avaliar as propriedades físico-químicas de um novo derivado do salicilato em cimentos endodônticos experimentais à base de cálcio. Dois derivados de salicilato foram sintetizados por meio de uma reação de trans esterificação do salicilato de metila com dois diferentes alcoóis (1,3-butilenoglicol dissalicilato-BD e pentaeritritol tetrassalicilato-PT) na proporção molar de 1: 3 e 1:6, respectivamente. Os produtos (BD e PT), foram caracterizados por espectroscopia infravermelho transformada de Fourier (FTIR) e espectroscopia de ressonância magnética nuclear (RMN). Os cimentos experimentais à base de cálcio foram preparados com a mesma pasta catalisadora (60% de MTA, 39% de N-etil o/p toluenosulfonamida e 1% de dióxido de titânio) e quatro concentrações diferentes de BD e PT nas pastas base (40/0 - controle, 35/5, 30/10 e 20/20) com 60% de óxido de bismuto. Os cimentos foram avaliados quanto ao tempo de endurecimento, à solubilidade (24 h, 7, 14 e 28 dias), resistência à tração diametral e ao módulo de elasticidade. Os dados foram analisados por ANOVA um ou dois fatores e as médias comparadas pelo teste de Tukey (p<0,05). A adição de PT reduziu o tempo de endurecimento dos materiais testados. Após 24 horas os cimentos 40/0 e 35/5 apresentaram maior solubilidade que os demais e após 14 e 28 dias o cimento 20/20 foi o que apresentou menor solubilidade (p<0,05). Após 7 dias o grupo 20/20 estabilizou a sua solubilidade. O cimento 40/0 apresentou os maiores valores e o cimento 20/20 apresentou os menores valores de resistência à tração diametral e módulo de elasticidade (p<0,05). A adição de PT a cimentos à base de cálcio possibilita benefícios ao tempo de presa e solubilidade.

Pentaerythritol Tetrasalicylate in the Chemical Composition of Root Canal Sealers.

The aim of this study was to synthesize and evaluate physicochemical properties of a new salicylate derivative in experimental calcium-based root canal sealers. Two salicylate derivatives were synthesized for the transesterification reaction of methyl salicylate with two different alcohols (1,3-butylenoglicol disalicylate-BD and pentaerythritol tetrasalicylate -PT) in molar ratio 1:3 and 1:6, respectively. The products (BD and PT), were characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Nuclear Magnetic Resonance spectroscopy (RMN). Calcium-based experimental sealers were prepared with the same catalyst paste (60% of MTA, 39% of n-ethyl-o-toluenesulfonamide, and 1% titanium dioxide) and four different concentrations of BD and PT in the base pastes (40/0 - control, 35/5, 30/10 and 20/20) with 60% of bismuth oxide. The experimental sealers were evaluated for setting time, solubility (24 h, 7, 14 and 30 days), diametral tensile strength and Young's Modulus. Data were analyzed by one- or two-way ANOVA with Tukey's test (p<0.05). The addition of PT reduced the materials setting time. After 24 h the sealer 40/0 and 35/5 had higher solubility, and after 14 and 28 days the sealer 20/20 showed the lowest solubility (p<0.05). After 7 days the sealer 20/20 stabilized its solubility. The sealer 40/0 presented the highest values and the 20/20 presented the lowest values of diametral tensile strength and Young's modulus (p<0.05). The addition of PT to calcium-based root canal sealers provides benefits to the setting time and solubility.

Replacing HEMA with alternative dimethacrylates in dental adhesive systems: evaluation of polymerization kinetics and physicochemical properties.

PURPOSE: To evaluate the mechanical and physical properties of experimental HEMA-containing and HEMA-free resin adhesives. MATERIALS AND METHODS: Experimental HEMA-free adhesives containing alternative dimethacrylates (bis-EMA 10 [B10], bis-EMA 30 [B30], PEG 400 [P400], PEG 1000 [P1000], PEG 400 UDMA [UP400]) were formulated and compared with a HEMA-containing adhesive (control). The adhesives were characterized by rheological analysis, polymerization kinetics (PK), water sorption (WS), and solubility (SL) tests. Flexural strength (FS) and flexural modulus (E) tests were performed under dry or wet conditions (distilled water or 70% ethanol solution). One-way and two-way ANOVA as well as Tukey's test were used to evaluate differences between groups (p < 0.05). RESULTS: The control group showed the lowest viscosity and was the only one with a degree of conversion lower than 50%. The control and the P1000 adhesive showed the statistically significantly highest WS (p < 0.05). The control and the UP400 adhesive showed the highest FS and E, and the dry-stored specimens showed more improved mechanical strength than did the wet-stored specimens (p < 0.05). CONCLUSION: The physicomechanical properties of some of the HEMA-free adhesives were substantially improved when compared with those of the control, indicating that they could be potential monomers for the development of HEMA-free adhesive systems.

Physical properties of MTA Fillapex sealer.

INTRODUCTION: The aim of this study was to evaluate and compare several physicochemical properties including working and setting times, flow, solubility, and water absorption of a recent calcium silicate-based sealer (MTA Fillapex; Angelus, Londrina, Brazil) and an epoxy resin-based sealer (AH Plus; Dentsply, Konstanz, Germany). METHODS: The materials were handled following the manufacturer's instructions. The working time and flow were tested according to ISO 6876:2001 and the setting time according to American Society for Testing and Materials C266. For solubility and water absorption tests, the materials were placed into polyvinyl chloride molds (8 × 1.6 mm). The samples (n = 10 for each material and test) were placed in a cylindrical polystyrene-sealed container with 20 mL deionized water at 37°C. At 1, 7, 14, and 28 days, the samples were removed from the solutions and blotted dry for solubility and water absorption tests. The data were analyzed using 1-way analysis of variance with the Tukey test (P < .05). RESULTS: MTA Fillapex showed the lowest values of flow, working and setting times, solubility, and water absorption (P < .05). The solubility and water absorption increased significantly over time for both materials in a 1- to 28-day period (P < .05). CONCLUSIONS: MTA Fillapex showed suitable physical properties to be used as an endodontic sealer.

Reabilitação estética em dentes anteriores com lesões de cárie proximais: relato de caso / Esthetic rehabilitation in anterior teeth with proximal carious lesions: case report

O objetivo do presente trabalho é o de descrever um caso de reabilitação estética na região dentária anterior. Paciente queixando-se das manchas escuras nos dentes anteriores superiores apresentava lesões de cárie nos dentes ântero-superiores, causando uma desarmonia estética no seu sorriso. Dentro do plano de tratamento reabilitador da paciente, realizaram-se restaurações classe III dos elementos dentários 11 e 12, classe IV do 21 e classe V do 13 e do 14. Frente ao caso clínico exposto, conclui-se que a reabilitação restauradora, além de promover saúde, pode proporcionar uma aparência estética mais favorável do sorriso, elevando a autoestima do paciente.

The aim of this study is to describe a case of esthetic rehabilitation in the maxillary incisive. Patient complaining of black stain on the maxillary teeth had carious lesions in teeth that cause great disharmony of your smile. Within the rehabilitation plan of patient, took place Class III restorations of the teeth 11 and 12, class IV of 21 and class V of the 13 and 14. It was concluded that, the present approach, allowed the anterior restorative rehabilitation, promote health and provide a more favorable aesthetic appearance of the smile, raising self-esteem of the patient.