Methacrylic monomer derived from cardanol incorporated in dental adhesive as a polymerizable collagen crosslinker.

OBJECTIVES: The aim of this study was to evaluate the influence on MMP inhibition, dentin adhesion and physicochemical properties of an adhesive system incorporated with polymerizable collagen crosslinker monomer derived from cardanol. METHODS: The intermediary cardanol epoxy (CNE) was synthesized through cardanol epoxidation, followed by synthesis of cardanol methacrylate through methacrylic acid solvent-free esterification. Zymographic analysis was performed to evaluate the substances' ability to inhibit gelatinolytic enzymes. Collagen crosslinkers were added into adhesives systems according to the following groups: Ybond Universal® (Control), Ybond® + 2 % proanthocyanidin (PAC), Ybond® + 2 % unsaturated cardanol (Cardanol) and Ybond® + 2 % cardanol methacrylate (CNMA). Degree of conversion (DC) of the adhesives was assessed by FT-IR. Disk-shaped specimens were prepared for water sorption (WS) and solubility (SL) tests. Human third molars were sectioned to expose medium dentin and restored according to the different adhesives used (n = 5). Then, the specimens were cut into 1 mm2 sticks to evaluate, after 24 h and 6-month aging, microtensile bond strength (µTBS) and nanoleakage by scanning electron microscopy. Data were analysed with ANOVA and Tukey's post-test (α = 0.05). RESULTS: CNMA and PAC completely inhibited all forms of gelatinolytic enzymes. Cardanol achieved a significantly lowest DC, while the other groups did not differ from each other (p > 0.05). PAC achieved significantly higher water sorption, while CNMA solubility was significantly lower when compared to the other adhesives (p < 0.05). PAC provided a statistically higher 24 h and 6-month aging bond strength. Intermediary similar µTBS were presented by control and CNMA (p = 0.108). All adhesives applied attained significantly reduced bond strength after aging (p < 0.05). Interfaces created using CNMA were almost devoid of silver deposits initially, however all groups showed large amounts of silver deposits on resin-dentin interface subjected to water aging. SIGNIFICANCE: Although CNMA was effective in inhibiting gelatinolytic enzymes, when incorporated into a universal adhesive it could not promote less degradation of the adhesive interface after water aging. Since it is a hydrophobic monomer, CNMA did not interact well with dentin collagen, however it reduced the solubility of the adhesive system besides not interfering in its polymerization.

Association of solvents improves selected properties of experimental dental adhesives.

The aim of the study was to evaluate how the association of solvents (tetrahydrofuran [THF], dimethyl sulfoxide [DMSO], ethanol [ET] or acetone [ACT]) with experimental dental adhesives affects selected properties of experimental dental adhesives and dentin bond durability. Six adhesive combinations were prepared containing: 30 % ET, 30 % ACT, 30 % THF, 28 % ET + 2 % DMSO (ET+DMSO), 15 % ethanol + 15 % THF (ET+THF), or 28 % THF + 2 % DMSO (THF+DMSO). Thirty-six molars (n = 6) were cut to expose the coronary dentin, and were randomly divided according to the adhesives. They were restored, and then cut into resindentin sticks (1 mm²), and stored in distilled water for 24 h or 6 months, until conducting the microtensile bond strength and nanoleakage tests. Other experiments performed with adhesives included viscosity assessment using a rheometer, and degree of conversion using Fourier-transform infrared spectroscopy (FTIR). The data were analyzed statistically using two-way ANOVA and Tukey's test (p < 0.05). The adhesive formulated exclusively with THF showed the highest viscosity, followed by ET+THF, which obtained the highest degree of conversion compared to ET, and THF alone. ET+DMSO obtained the highest 24-h and aged bond strengths (p < 0.05). ET+THF increased the nanoleakage slightly after 6 months, but attained the only gap-free adhesive interface among all the groups. The combination of alternative solvents, particularly THF, with conventional ones (ET) has improved chemical properties, and the dentin bonding of experimental simplified adhesives.

Association of solvents improves selected properties of experimental dental adhesives

Abstract: The aim of the study was to evaluate how the association of solvents (tetrahydrofuran [THF], dimethyl sulfoxide [DMSO], ethanol [ET] or acetone [ACT]) with experimental dental adhesives affects selected properties of experimental dental adhesives and dentin bond durability. Six adhesive combinations were prepared containing: 30 % ET, 30 % ACT, 30 % THF, 28 % ET + 2 % DMSO (ET+DMSO), 15 % ethanol + 15 % THF (ET+THF), or 28 % THF + 2 % DMSO (THF+DMSO). Thirty-six molars (n = 6) were cut to expose the coronary dentin, and were randomly divided according to the adhesives. They were restored, and then cut into resindentin sticks (1 mm²), and stored in distilled water for 24 h or 6 months, until conducting the microtensile bond strength and nanoleakage tests. Other experiments performed with adhesives included viscosity assessment using a rheometer, and degree of conversion using Fourier-transform infrared spectroscopy (FTIR). The data were analyzed statistically using two-way ANOVA and Tukey's test (p < 0.05). The adhesive formulated exclusively with THF showed the highest viscosity, followed by ET+THF, which obtained the highest degree of conversion compared to ET, and THF alone. ET+DMSO obtained the highest 24-h and aged bond strengths (p < 0.05). ET+THF increased the nanoleakage slightly after 6 months, but attained the only gap-free adhesive interface among all the groups. The combination of alternative solvents, particularly THF, with conventional ones (ET) has improved chemical properties, and the dentin bonding of experimental simplified adhesives.

Oral tranexamic acid associated with platelet transfusion to prevent hemorrhage in a patient with Glanzmann thrombasthenia.

Glanzmann thrombasthenia (GT) is a rare genetic disorder that alters platelet function. The clinical manifestations include purpura, epistaxis, gingival bleeding, and menorrhagia. For patients with GT, conventional surgical dental treatment may result in hemorrhagic complications. There are many reported ways to prevent hemorrhage in patients with GT during surgical procedures but no standardized recommendations. In this case study, a woman diagnosed with GT required 2 types of surgery (periodontal surgery and third molar extractions), which were performed on separate days. Preoperative evaluation and planning with a hematology service led to the transfusion of 1 pack of platelet concentrate immediately before each surgery. Additionally, the patient was prescribed oral tranexamic acid, which was started 1 day before each surgery and continued for 3 additional days. A distal wedge procedure was performed for the mandibular right third molar, and later the maxillary and mandibular left third molars were extracted. The use of oral tranexamic acid associated with a single platelet bag was effective in the present case, and no bleeding or thrombotic events were observed after either surgery. Although this coagulopathy is rare, dentists must be aware of its implications, which necessitate specific precautions for oral surgical procedures. Multidisciplinary integration and surgical planning can reduce the risk of complications for the patient.

Synthesis and characterization of a new methacrylate monomer derived from the cashew nut shell liquid (CNSL) and its effect on dentinal tubular occlusion.

OBJECTIVE: The aim of this study was to synthesize, to characterize and to evaluate the effects on tubular occlusion of new monomer derived from cashew nut shell liquid (CNSL), also studying the effects of acid challenge (AC) on dentin surfaces treated with desensitizers. METHODS: The intermediary cardanol-epoxy (CNE) was synthesized through epoxidation of CNSL, followed by synthesis of cardanol-methacrylate-epoxy (CNME) through methacryloyl chloride esterification. Products were purified through chromatography column and characterized by Fourier transform infrared spectrometry and nuclear magnetic resonance. Resinous dentin desensitizers were formulated containing either unsaturated cardanol (CNU), CNE or CNME. Dentin disks were divided into seven groups: SL - Smear-layer, EDTA - EDTA-treated only, GLUMA - Gluma Desensitizer, OCB - One Coat Bond, CNU - CNU desensitizer, CNE - CNE desensitizer and CNME - CNME desensitizer. Dentinal fluid rate (DFF) was obtained using a Flodec equipment and tubular occlusion employing a scanning electron microscope (SEM), before and after AC. Data of DFF were submitted to two-way ANOVA and Tukey's test (p<0.05). RESULTS: GLUMA showed the lower reduction in DFF when compared to the other products, which were statistically similar. Even after AC, CNME presented the most homogenous and occluded surface, while CNE and CNU were partially removed, GLUMA was completely removed and OCB keep an occluded, but irregular surface. SIGNIFICANCE: CNME showed a great reduction of DFF and a homogenous occluded surface, suggesting that it may be a suitable and acid-resistant treatment option for dentine hypersensitivity.

Lesões cervicais em área estética com exposição dos canais radiculares: o papel de uma abordagem multidisciplinar / Cervical lesions in the aesthetic zone with exposure of radicular canals: the role of a multidisciplinary approach

Introdução: algumas situações clínicas não se apresentam como ideais para o tratamento restaurador adequado e o profissional deve encontrar formas alternativas de acesso adequado à margem gengival. Objetivo: apresentar um caso de lesões cervicais com exposição vestibular de canais radiculares no qual a interação entre Endodontia, Odontologia Restauradora e Periodontia foi fundamental para seu sucesso. Relato de caso: o paciente apresentou lesões de cárie cervical subgengivais, com exposição dos canais radiculares dos dentes anteriores. O tratamento inicial foi realizado por meio de uma adaptação do isolamento com lençol de borracha. Após instrumentação, foi introduzida nos canais guta-percha recoberta com vaselina, para auxiliar na restauração temporária da superfície vestibular. O tratamento endodôntico e periodontal foi concluído posteriormente e os dentes foram restaurados durante a cirurgia periodontal, com resina composta. Conclusões: deve-se sempre considerar o planejamento multidisciplinar no tratamento de casos atípicos, bem como adaptar procedimentos convencionais para a abordagem de casos complexos, visando o restabelecimento da saúde, estética e função do paciente.

Reconstrução de dente anterior fraturado com restauração direta associada a pino de fibra de vidro ­ relato de caso / Fractured anterior tooth reconstruction with direct restoration associated with glass fiber pin ­ case report

O relato de caso tem por objetivo descrever as etapas de planejamento e o protocolo restaurador para um caso de reconstrução de dente anterior fraturado por meio de restauração direta com resina composta associada a pino de fibra de vidro, além de discutir os procedimentos necessários para a obtenção de restaurações satisfatórias nessa região. Paciente GLA, leucoderma, 14 anos de idade, vítima de acidente doméstico, com fratura coronária nos dentes 11 e 21. Após anamnese, exame clínico e radiográfico, constatou-se fratura coronária do tipo VI no dente 11, com tratamento endodôntico já realizado, e do tipo III no dente 21. Em virtude da idade do paciente, para o plano de tratamento optou-se pela utilização de um retentor intrarradicular estético, pino de fibra de vidro, associado à restauração direta em resina composta, dada às condições clínicas do remanescente dentário, e para o dente 21, optou-se pela restauração direta em resina composta. Dentes fraturados e submetidos ao tratamento endodôntico devem ser reconstruídos tendo por base um planejamento criterioso. Com a evolução das resinas compostas e dos sistemas adesivos, associados à técnica de condicionamento ácido de esmalte e dentina, tornou-se possível a execução de tratamentos restauradores estéticos mais conservadores (AU).

The objective of this case report was to describe the planning stages and the restorative protocol for a fractured anterior tooth reconstruction by means of direct restoration with composite resin associated with fiberglass pin, in addition to discussing the procedures necessary for obtaining satisfactory restorations in this region. The patient, GLA, leucoderma, 14 years old, was victim of a domestic accident, resulting on a coronary fracture in teeth 11 and 21. After anamnesis, clinical and radiographic examination, a type VI coronary fracture was found in tooth 11 with endodontic treatment and type III in tooth 21. Due to the age of the patient, the treatment plan included the use of an aesthetic intra-radicular retainer, fiberglass pin, associated to direct restoration in composite resin given the clinical conditions of the dental remnant, while the direct restoration in composite resin was chosen for element 21. Fractured teeth as those submitted to endodontic treatment should be reconstructed based on careful planning. With the evolution of composite resins and adhesive systems, associated with the acid etching technique of enamel and dentin, it became possible to perform more conservative esthetic restorative treatments (AU).

Prevalência de fissuras labiopalatinas em um hospital de referência do nordeste do Brasil / Prevalence of cleft palate in a hospital of reference in northeastern of Brazil

O propósito deste trabalho foi verificar a ocorrência de fissuras labiopalatais em pacientes atendidos no Hospital Infantil Albert Sabin (HIAS) em 15 anos. Foram analisados dados quanto ao sexo e tipo de fissura verificando-se que 50,38% dos pacientes eram do sexo masculino e que 80% dos casos apresentaram fissura transforame. Relacionando as variáveis, é notória a prevalência do sexo feminino nas fissuras pós-forame (62%) e fissuras pré-forame unilateral direita (87,5%). Confirmando relatos da literatura, houve uma leve predileção pelo sexo masculino, a fissura transforame foi a mais prevalente e o lado esquerdo foi o mais acometido. Os pacientes fissurados necessitam de um uma equipe multi e interdisciplinar no diagnóstico, planejamento e proservação do caso.

The purpose of this study was to verify the occurrence rates in patients with cleft lip/palate treated at the Hospital Infantil Albert Sabin (HIAS) in 15 years. Data regarding sex and type of cleft were surveyed and was found that 50.38% of patients were male and 80% of cases had tranforamen cleft. Relating the variables, there is a notorious prevalence of females in the post- foramen fissures (62%) and right unilateral clefts pre-foramen (87.5%). Confirming reports in the literature, there was a slight predominance of males, the transforamen fissure is the most prevalent fissure in general and the left side was more affected. The cleft patients require a multidisciplinary team for diagnosis, treatment and following.