Optimization for Bone Samples Embedded in Methyl Methacrylate

Abstract

Our aim was to update a standard technique for embedding bone samples, with or without implants, using methyl methacrylate (MMA) to obtain reliable optical microscopy images from mineralized bone tissues and bone-implant interfaces. In addition, comparative studies were carried out using different temperatures throughout the polymerization process. Twenty-two New Zealand rabbit calvaria and femur bone samples with or without implants were used. The samples were fixed in 10% buffered formalin, dehydrated in an ascending alcohol series, and infiltrated in methyl methacrylate solutions (I, II and III). The specimens were divided into three groups. Groups 1 and 2 were polymerized at 24°C ± 5°C, while Group 3 was polymerized at 60°C. Group 1 and 2 obtained homogeneous, transparent, crystalline polymerization. Group 3 presented multiple bubbles (ø 2 – 3 mm), depressions, folds and even rupture of the vial container. The MMA bone samples polymerized at room temperature, showed good embedded, low hardness index, thin cuts, and effective staining.