Effect of intracanal medications on the interfacial properties of reparative cements

OBJECTIVES: The purpose of the present study was to evaluate the effect of calcium hydroxide with 2% chlorhexidine gel (HCX) or distilled water (HCA) compared to triple antibiotic paste (TAP) on push-out bond strength and the cement/dentin interface in canals sealed with White MTA Angelus (WMTA) or Biodentine (BD). MATERIALS AND METHODS: A total of 70 extracted human lower premolars were endodontically prepared and randomly divided into 4 groups according to the intracanal medication, as follows: group 1, HCX; group 2, TAP; group 3, HCA; and group 4, control (without intracanal medication). After 7 days, the medications were removed and the cervical third of the specimens was sectioned into five 1-mm sections. The sections were then sealed with WMTA or BD as a reparative material. After 7 days in 100% humidity, a push-out bond strength test was performed. Elemental analysis was performed at the interface, using energy-dispersive spectroscopy. The data were statistically analyzed using analysis of variance and the Tukey test (p < 0.05). RESULTS: BD presented a higher bond strength than WMTA (p < 0.05). BD or WMTA in canals treated with calcium hydroxide intracanal medications had the highest bond strength values, with a statistically significant difference compared to TAP in the WMTA group (p < 0.05). There were small amounts of phosphorus in samples exposed to triple antibiotic paste, regardless of the coronal sealing. CONCLUSIONS: The use of intracanal medications did not affect the bond strength of WMTA and BD, except when TAP was used with WMTA.

Effect of ultrasonic agitation on push-out bond strength and adaptation of root-end filling materials

OBJECTIVES: This study evaluated the effect of ultrasonic agitation of mineral trioxide aggregate (MTA), calcium silicate-based cement (CSC), and Sealer 26 (S26) on adaptation at the cement/dentin interface and push-out bond strength. MATERIALS AND METHODS: Sixty maxillary canines were divided into 6 groups (n = 10): MTA, S26, and CSC, with or without ultrasonic activation (US). After obturation, the apical portions of the teeth were sectioned, and retrograde cavities were prepared and filled with cement by hand condensation. In the US groups, the cement was activated for 60 seconds: 30 seconds in the mesio-distal direction and 30 seconds in the buccal-lingual direction, using a mini Irrisonic insert coupled with the ultrasound transducer. After the materials set, 1.5-mm thick sections were obtained from the apexes. The presence of gaps and the bond between cement and dentin were analyzed using low-vacuum scanning electron microscopy. Push-out bond strength was measured using a universal testing machine. RESULTS: Ultrasonic agitation increased the interfacial adaptation of the cements. The S26 US group showed a higher adaptation value than MTA (p < 0.05). US improved the push-out bond strength for all the cements (p < 0.05). CONCLUSIONS: The US of retrograde filling cements enhanced the bond to the dentin wall of the root-end filling materials tested.

O uso das proteínas ósseas morfogenéticas na Implantodontia - revisão de literatura / The use of morphogenetic protein in Implantology - literature review

A descoberta de materiais de enxerto para auxiliar na regeneração óssea ampliou as perspectivas da reabilitação oral. As proteínas ósseas morfogenéticas (BMPs) têm sido amplamente estudadas para a regeneração de áreas com defeitos ósseos. As BMPs são fatores de crescimento derivados da matriz óssea e que induzem a diferenciação de células mesenquimais indiferenciadas em osteoblastos. Algumas aplicações das BMPs na Implantodontia incluem a correção de defeitos alveolares pós-extração, aumento de rebordo alveolar em pacientes edêntulos, levantamento de seio maxilar, entre outros. As BMPs apresentam vantagens como a ausência de um segundo sítio cirúrgico para obtenção de tecido ósseo, resultando em menor tempo de reparo e maior comodidade aos pacientes. Além disso, a utilização das BMPs não se limita pelo tamanho do defeito podendo ser utilizada em defeitos extensos. Uma limitação das BMPs está relacionada ao custo elevado, sendo por este motivo pouco utilizada pelos profissionais cotidianamente. Diversos estudos pré-clínicos e clínicos demonstram o sucesso da utilização das proteínas ósseas morfogenéticas na neoformação óssea. O objetivo da presente revisão foi analisar a literatura relacionada à utilização das BMPs nos diferentes procedimentos envolvidos na área da Implantodontia. Estudos em animais empregando as BMPs concomitantemente com implantes osseointegrados demonstram o sucesso da utilização das proteínas para a neoformação óssea. Inúmeros estudos clínicos comprovam a viabilidade e segurança da utilização das BMPs em procedimentos cirúrgicos. Dos resultados presentes na literatura, pode-se concluir que as proteínas ósseas morfogenéticas são uma alternativa viável e segura, com grande potencial para a regeneração óssea na Implantodontia.

Development of bone graft materials has improved the options of treatment in rehabilitation therapy. Bone morphogenetic proteins (BMPs) have been widely studied for regeneration of bone defects. Bone morphogenetic proteins are growth factors derived from bone matrix. These proteins induce mesenchymal cells to differentiate into osteoblast cells, producing new bone. Some applications of BMPs in Implantology include alveolar correction in extraction sites, alveolar ridge augmentation in edentulous patients, and sinus floor augmentation. The bone morphogenetic proteins present some advantages as the absence of a second surgical site. The procedure is less traumatic and result in lower time for repair, which is a desirable property for the patients. Furthermore, the use of BMPs is not limited by the size of the defect. The proteins can be used in large defects without any restriction. However, BMPs have a high cost, which limits its use by the professionals. Several laboratorial and clinical studies have shown the success of the use of BMPs on bone formation. The aim of the present review was to analyze the studies regarding the use of BMPs in different procedures in Implantolo¬gy. Studies in animals using BMPs with dental implants show the success of the therapy and further studies in humans demonstrate the possibility of bone formation in cases of defects.The BMPs are able to induce bone regeneration around dental implants. Furthermore, several clinical studies verified feasibility and safety when using BMPs in surgery procedures. Bone morphogenetic proteins can be considered a potential and safe alternative in bone regenera¬tion in Implantology.

Propriedades físico-químicas e biológicas de cimento experimental à base de Portland associado a diferentes radiopacificadores / Physical, chemical and biological properties of an experimental Portland-based cement with different radiopacifier agents

O objetivo do estudo foi avaliar as propriedades físicas, químicas e biológicas de um cimento experimental à base de Portland contendo diferentes agentes radiopacificadores. Os cimentos foram divididos em 6 grupos: 1. MTA-Angelus branco (controle), 2. cimento Portland branco (CP), 3. CP com 20% de óxido de zircônio (OZ), 4. CP/50% OZ, 5. CP com 20% de tungstato de cálcio (TC) e 6. CP/50% TC. As proporções foram determinadas em peso (80 e 50% de CP para 20 e 50% de radiopacificadores, respectivamente). Os cimentos experimentais foram manipulados utilizando 0,3 mL de líquido composto por 80% de água destilada e 20% de propilenoglicol, em volume. A caracterização dos materiais foi realizada em microscopia eletrônica de varredura (MEV), no modo EDS e em difratômetro de raios-X (XRD). Para os testes de radiopacidade, escoamento, espessura de filme e solubilidade foram seguidas as especificações no 57 da ANSI/ADA (2000). Na determinação do tempo de presa, foi empregada a norma ASTM C266/2008. Na análise do pH e liberação de íons cálcio foram analisados os períodos de 3, 24, 72 e 168 horas. Para análise da descoloração dentária, foram realizadas análises em espectrofotômetro, estereomicroscopia e MEV. Para análise da resposta inflamatória, foi utilizado o teste de implantação em subcutâneo de ratos. A utilização do óxido de zircônio e do tungstato de cálcio em combinação com o cimento Portland resultou no desenvolvimento de cimentos que exibiram uma radiopacidade próxima (20% de radiopacificadores) ou acima (50%) do recomendado pela norma no 57 da ANSI/ADA; tempo de presa mais prolongado, espessura de filme menor e escoamento mais elevado em comparação com o MTA-Angelus; solubilidade adequada e comparável ao MTA-Angelus, elevado pH e liberação de íons cálcio superior ao MTA-Angelus nos períodos iniciais e similar aos 7 dias, ausência de descoloração dentária e resposta inflamatória semelhante ao MTA-Angelus...

The aim of the study was to evaluate the physical, chemical and biological properties of an experimental calcium silicate-based cement with different concentrations of the radiopacifiers zirconium oxide and calcium tungstate. The materials were divided in 6 groups: 1. White MTA (control), 2. White Portland cement (PC), 3. PC with 20% zirconium oxide (ZO), 4. PC/50% ZO, 5. PC with 20% calcium tungstate (CT) and 6. PC/50% CT. The proportions were determined by weight. The cements were manipulated using 0.3 mL of liquid composed of 80% distilled water and 20% propylene glycol. The control was manipulated according to manufacturers instructions. The characterization of the materials was performed using scanning electron microscopy (SEM) in EDS mode and X-ray diffractometrer (XRD). For radiopacity, flowability, film thickness and solubility test, the specifications no 57 of ADA (2000) was followed. To determine the setting time, ASTM C266/2008 specifications was followed. For pH and calcium ion release assessment, the periods of 3, 24, 72 and 168 hours were evaluated. The analysis of dental discolouration was performed using spectrophotometer, stereomicroscopy and SEM. To evaluate the inflammatory response, the test of subcutaneous implantation in rats was used. The use of zirconium oxide and calcium tungstate in association with Portland cement resulted in development of cements with radiopacity nearly (20% radiopacifiers) or above (50%) the recommended by ANSI/ADA specifications n a 57, more prolonged setting time, lower film thickness and higher flowability in comparison with MTAAngelus, an adequate and comparable solubility with MTA-Angelus, high pH and calcium ion release higher than MTA-Angelus in the initial periods and similar at 7 days, absence of dental discolouration and inflammatory response similar to that presented by MTA-Angelus...