RESUMEN
60 curved root canals of permanent teeth with angles of curvature ranging from 15°to 40°(Schneider's methodology)were prepared using the instruments of Hyflex CM(HC) and ProTaper(PT) Universal respectively(n=30).Using standardized pre-and post-instrumentation paralleling periapical radiographs,canal curvature was determined by image analysis software and the clinical shaping effect of Hyflex CM and ProTaper rotary NiTi files were compared.The canal curvature in group HC and PT decreased by 4.54°±3.25° and 5.63°±3.84° respectively(between pre-and post-treatment in both groups,P0.05).Hyflex CM can meet the clinical necessity for the instrumentation of curved root canals.
RESUMEN
Objective To discuss the treatment action and mechanism of Wenjing Tongluo Formula on oxaliplatin-induced perpheral neurotoxicity in rats. Methods Intraperitoneal injection was used to inject oxaliplatin 4 mg/kg to establish oxaliplatin-induced peripheral neurotoxicity rat models. Female Wistar rats were randomly divided into normal group, model group, and TCM group. TCM group was given Wenjing Tongluo Formula to soak rats’ limbs and tails. Rats in the model group were soaked with deionized water for comparison. Rats in the normal group received intraperitoneal injection with 5%glucose. Algesia hypersensitivity and anaphylaxis were detected under the mechanical stimulation and temperature. Immunohistochemical method was used to detect the expression of GFAP in L4-L6 spinal dorsal horn of rats. Explore the level of GLT-1 in L4-L6 dorsal root ganglia by RT-PCR. Results Rats in model group showed obvious behavioral changes compared with normal group (P<0.05);Rats in the TCM group improved in behavioristics compared with model group (P<0.01);number of positive cells in GFAP of rats in the model group increased compared with normal group (P<0.05);the increase in the TCM group was not obvious. Compared with normal group, astrocytes in spinal dorsal horn of model group were enlarged, protuberances increased, became coarse, and GLT-1 mRNA is decreased (P<0.05, P<0.01). Compared with model group, active cells and protuberances in the TCM group decreased (P<0.01), GLT-1 mRNA is increased (P<0.01). Conclusion Wenjing Tongluo Formula can improve behavioral changes of model rats under temperature and mechanical stimulation, probably related to harmful signal transmission induced by inhibition of astrocyte in spinal dorsal horn.