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.