Effectiveness of Er:YAG laser in cavity preparation for retrograde filling--in vitro study.

The purpose of this study was to determine the sealing quality of Super EBA cement in laser prepared root-end cavities in comparison with root-end cavities classically prepared with steel burrs. Two groups of three millimeter root sections were prepared. The first group was prepared with the Er:YAG laser and the second group with a steel burr mounted on a surgical handpiece. The sections were filled with Super EBA cement and tested for leakage with fluid transport techniques. The sealing quality of Super EBA cement in the classically prepared root-end cavities was better, but there was no statistically significant difference between the two preparation techniques. The possible reason for greater leakage in the laser prepared root-end cavities was probably the irregular shape of the root-end cavity.

The prevalence of idiopathic osteosclerosis and condensing osteitis in Zagreb population.

The aim of this study was to determine the prevalence of idiopathic osteosclerosis (IO) and condensing osteitis (CO) in Zagreb patient population sample according to age and sex, localization in the jaw, as well as dental relationship between IO and CO lesions. A retrospective study was performed using orthopantomograms of 1200 patients who underwent dental treatment. Descriptive characteristics of radiopacities, including the size and information concerning the tooth involved, were recorded and processed using chi2-test. A total of 114 radiopacities were identified, 34 IO in 29 subjects (16 female and 13 male, mean age 35), and 80 CO in 69 subjects (38 female and 31 male, mean age 37). There were no significant sex differences. Both CO and IO showed greater predilection for occurrence in the premolar to molar region of the mandible. Our results indicated a low prevalence of IO and CO in the population of Zagreb. Our findings support the theory that IO lesions should be considered developmental variants of normal bone architecture unrelated to local stimuli, whereas CO lesions could be considered reactive formations related to teeth with deep caries, large restoration, or pulpitis.