Assessing the efficacy of citrus aurantifolia extract on smear layer removal with scanning electron microscope.

INTRODUCTION: The purpose of this study was to determine the effects of citrus aurantifolia (CA) extract on smear layer removal in different parts of root canals. MATERIALS AND METHODS: Thirty-nine single-rooted human teeth were randomly divided into three experimental (n=12) and one control (n=3) groups. Teeth were instrumented using MTwo rotary instruments. Root canals were irrigated with NaOCl during instrumentation. The canals in each group were irrigated with one of the following: completed mixture of citrus aurantifolia extracts, 17% EDTA, and alcoholic extract of CA. Distilled water was used for the control group. The irrigants were left within the canal for 20 minutes, and then rinsed with normal saline solution. Teeth were subsequently split longitudinally into 2 halves, and the canals were examined by a scanning electron-microscope. Cleanliness was evaluated using a five point scoring system. RESULTS: Statistical significant difference was found between groups (P<0.05). The smear layer was more effectively removed with 17% EDTA compared to alcoholic CA extract. However, they were both able to remove the smear layer in the coronal segment. Completed CA extract removed more smear layer in coronal and middle parts compared with the alcoholic extract (P=0.001); however, there was no significant difference in the apical part. CONCLUSION: Both of the alcoholic and completed mixtures of citrus aurantifolia extracts were not able to effectively remove smear layer compared with 17% EDTA during root canal therapy.

Antinociceptive effects of the essential oil of Dracocephalum kotschyi in the mouse writhing test.

PURPOSE: Dracocephalum kotschyi is a wild-growing flowering plant belonging to the family Labiatae and found abundantly in Iran. This plant has been used in Iran folk medicine as analgesic. METHODS: The Dracocephalum kotschyi essential oil was isolated and studied on writhing test a visceral pain model in mice. Different constituents of the essential oil were determined by gas chromatography mass spectrophotometry technique. RESULTS: Limonene, verbenone, alpha-terpineol, perillyl alcohol and caryophyllene were the major constituents of the essential oil. The essential oil in doses (mg kg-1) used 12.5 (13.9%, P<0.05), 25 (43.1%, P<0.01), 50 (68.7%, P<0.01), 75 (39.8%, P<0.01) induced significant reduction in pain response when compared to control. The ED50 was 61.61 mg kg(-1). Hyoscine (1 mg kg(-1)) and indomethacin (5 mg kg(-1)) induced significant (P<0.01) reductions (74.9% and 76.7% respectively) in pain response in comparison to control. CONCLUSION: This study confirms that antinociceptive properties of D. kotschyi are comparable to those of hyoscine and indomethacin used. Presence of limonene and alpha-terpineol might be responsible for antinociceptive properties of this essential oil. Further studies are necessary to find out a place for it in antispasmodic therapies in human

Antinociceptive effects of Teucrium polium L total extract and essential oil in mouse writhing test.

In this study, the effect of Teucrium polium L, a wild-growing flowering plant belonging to the family Labiatae and found abundantly in Iran was studied on writhing test, a visceral pain model in mice. The total extract and essential oil were administered intraperitoneally 30 min before acetic acid 0.6% injection. Total extract in doses (mg x kg(-1)) of 150 (39.13%, P<0.001), 225 (65.44%, P<0.001), 300 (21.41%, P<0.01) induced reduction in writhing response as compared to control with the ED(50) 67.92 mg x kg(-1). The essential oil in doses (mg x kg(-1)) of 9.37 (35.22%, P<0.001), 18.75 (59.63%, P<0.001), 37.5 (86.60%, P<0.001), 75 (90.22%, P<0.001) and 150 (78.58%, P<0.001) induced significant reduction in writhing response when compared to control with the ED(50) of 29.41 mg x kg(-1). In order to ensure the importance of essence in production of visceral antinociception, the extract free from essential oil was prepared and injected into mice at a dose of 225 mg x kg(-1) (the most effective dose of the extract) which in comparison to total extract, the antinociception, reduced from 65.44 to 49.85% (P<0.001). It is concluded that essential oil is responsible for analgesic properties of T. polium. This study confirms the antivisceral pain properties of T. polium comparable to those of hyoscine and indomethacin and suggests a good place for it in antispasmodic therapies in human. The presence of flavonoids and sterols might be responsible for the anti-inflammatory activity of this plant.