Influence of size and insertion depth of irrigation needle on debris extrusion and sealer penetration

OBJECTIVES: To determine the effect of size and insertion depth of irrigation needle on the amount of apical extruded debris and the amount of penetration depth of sealer using a confocal laser scanning microscope (CLSM). MATERIALS AND METHODS: Twenty maxillary premolars were assigned to 2 groups (n = 10), according to the size of needle tip, 28 G or 30 G. Buccal roots of samples were irrigated with respective needle type inserted 1 mm short of the working length (WL), while palatal roots were irrigated with respective needle type inserted 3 mm short of the WL. Prepared teeth were removed from the pre-weighed Eppendorf tubes. Canals were filled with F3 gutta-percha cone and rhodamine B dye-labeled AH 26 sealer. Teeth were transversally sectioned at 1 and 3 mm levels from the apex and observed under a CLSM. Eppendorf tubes were incubated to evaporate the irrigant and were weighed again. The difference between pre- and post-weights was calculated, and statistical evaluation was performed. RESULTS: Inserting needles closer to the apex and using needles with wider diameters were associated with significantly more debris extrusion (p < 0.05). The position of needles and level of sections had statistically significant effects on sealer penetration depth (p < 0.05 for both). CONCLUSIONS: Following preparation, inserting narrower needles compatible with the final apical diameter of the prepared root canal at 3 mm short of WL during final irrigation might prevent debris extrusion and improve sealer penetration in the apical third.

Effects of biomass smoke on pulmonary functions: a case control study.

BACKGROUND: Biomass smoke is the leading cause of COPD in developing countries such as Turkey. In rural areas of Turkey, females are more exposed to biomass smoke because of traditional lifestyles. AIM: The aim of this study was to determine the adverse effects of biomass smoke on pulmonary functions and define the relationship between duration in years and an index (cumulative exposure index) with altered pulmonary function test results. PARTICIPANTS AND METHODS: A total of 115 females who lived in the village of Kagizman (a borough of Kars located in the eastern part of Turkey) and were exposed to biomass smoke were included in the study. The control group was generated with 73 individuals living in the same area who were never exposed to biomass smoke. RESULTS: Twenty-seven (23.8%) females in the study group and four (5.5%) in the control group had small airway disease (P=0.038). Twenty-two (19.1%) females in the study group and ten (13.7%) in the control group had obstruction (P=0.223). Twenty (17.3%) females in the study group who were exposed to biomass smoke had restriction compared with ten (13%) in the control group (P=0.189). The duration needed for the existence of small airway disease was 16 years, for obstructive airway disease was 17 years, and for restrictive airway disease was 17 years. The intensity of biomass smoke was defined in terms of cumulative exposure index; it was calculated by multiplying hours per day, weeks per month, and total years of smoke exposure and dividing the result by three. CONCLUSION: Exposure to biomass smoke is a serious public health problem, especially in rural areas of developing countries, because of its negative effects on pulmonary functions. As the duration and the intensity of exposure increase, the probability of having altered pulmonary function test results is higher.