Residual antibacterial effect of calcium hydroxide combined with chlorhexidine gel as an intracanal medicament.

INTRODUCTION: Bacterial elimination from the root canal system is considered as an essential factor for a successful endodontic treatment. AIMS: To investigate both in vitro and in vivo efficacy of calcium hydroxide paste (CH) combined with 2% chlorhexidine gel (CHX) at various time intervals on Enterococcus faecalis (E.f) when used as an intracanal medicament (ICM). MATERIALS AND METHODS: For the in vitro study, 45 single-rooted teeth were used. After instrumentation, roots were infected with E.f and then divided into three groups (gps) (15 n/gp) according to the time interval for the medicament to be left inside the canal (1 week, 2 weeks and 3 weeks). ICM used was 2% CHX combined with CH (CH + CHX). At the end of each time interval, the antibacterial effect was evaluated using the agar diffusion test. For the in vivo study, 45 single-rooted teeth were selected. After sterilisation and access opening, the first pre-treatment sample was taken, then after instrumentation second post-instrumentation sample was obtained. Later, teeth were divided into 3 gps (15 n/gp) (1 week, 2 weeks and 3 weeks) according to the time interval for the medicament to be left inside the canal. ICM used was 2% CH + CHX. After each period, the third post-medication sample was taken. ANOVA and Tukey post hoc tests were used for statistical analysis. RESULTS: Both in vitro and in vivo studies have found that 2% of CH + CHX had a significant antibacterial effect for 1 week and 2 weeks. However, the antibacterial effect was significantly decreased after 3 weeks. CONCLUSIONS: CH + CHX can be used successfully for the reduction of E.f for 14 days when used as ICM.

Salvage of fractured abutment screw by transfer cap screw replacement (original study).

Salvage of fractured abutment screw is one of the critical complications, which can be solved in different ways. In this study, an innovative approach is introduced to solve this problem. It is a relatively simple, non-invasive technique, which would provide an excellent result when executed with ultimate care and precision.