Aim of the study: to investigate over the course of two time periods the biocompatibility through reaction of rats' subcutaneous tissue to three different intracanal medications (Neem oil, double antibiotic paste (DAP), and calcium hydroxide Ca (OH)2).
Methodology: Forty-eight Albino rats were distributed into four groups according to the type of intracanal medicament (n = 12): Ca(OH)2, Double antibiotic paste (DAP), Neem oil and a control group. Each group was further subdivided into two subgroups according to the time interval. Polyethylene tubes injected with one of the experimental medicaments were implanted into the dorsal subcutaneous tissues of the rats while empty tubes served as controls. After 7 and 21 days the implants with the surrounding tissue were excised. Qualitative and quantitative analysis were carried out for the stained histological sections. Statistical analysis was performed using Kruskal-Wallis test to compare between the groups and Wilcoxon signed-rank test to analyze the changes by time within each group.
Results: At 7 days: Ca(OH)2 group was associated with a severe significant inflammatory reaction followed by Neem oil which had a moderate inflammatory reaction, the difference was statistically significant. At 21 days, the severity of inflammation decreased significantly in all groups. DAP had the lowest inflammatory reaction with no significant difference between it and the control group at 7 and 21 days.
Conclusions The severity of the inflammatory reaction decreased over time in all groups. DAP could be considered the most biocompatible agent followed by Neem oil.