The reaction of rat connective tissue to polyethylene tube implants filled with Hydron or gutta-percha.

A subcutaneous tube implant study was conducted on adult Sprague-Dawley rats. Polyethylene tubes sealed at one end were filled flush to the open end with Hydron or gutta-percha and sealer. These implants were immediately placed into dorsal subcutaneous connective tissue for periods ranging from three weeks to 6 months.

A comparison of the marginal leakage of retrograde techniques.

An investigation of the apical seal of the most popular retrograde techniques was attempted. Ninety extracted maxillary central incisors were instrumented and obturated, and various apical procedures were performed. The depth of penetration of 2 percent methylene blue dye was used to evaluate the apical seal.

A comparison of the marginal adaptation of retrograde techniques: a scanning electron microscopic study.

An investigation of the most popular retrograde technique for their marginal adaptation to dentin was attempted. Forty extracted maxillary central incisors were instrumented and obturated, and various apical procedures were performed. The scanning electron microscope was used to record the results.