RESUMO
Objective @#To explore the "clinical normal reference range" of pulpal blood flow (PBF) in the physiological state in an effort to provide a reference for clinical diagnosis and treatment.@* Methods@# According to the working principle and operational considerations of laser Doppler flowmetry (LDF), the PBF blood flow value of the first molars of the upper and lower mandibles of normal adults was detected by LDF, and the clinical reference value range under physiological conditions was analyzed and calculated. The differences in PBF values by sex, dental position and location (left and right side, upper and lower jaw) were analyzed. @*Results @#A total of 200 normal adult participants with an average age of (22.76 ± 3.26) years were included. The cohort included 95 males and 105 females, with a total of 800 first molars. Neither the PBF values of the left and right first molars nor the PBF values of the upper and lower first molars in males or females significantly differed (P>0.05). The PBF value for females was higher than that of males. Specifically, the clinical reference PBF values for males and females were (8.56 ± 3.25) PU and (9.51 ± 3.47) PU, respectively.@*Conclusion @#The PBF values of normal adult first molars in healthy subjects were higher in females than in males, and in the PBF values of first molars of the same sex did not significantly differ between the left side and right side or upper and lower jaw; these values could be used as a reference for the selection of control teeth.
RESUMO
Objective@#To observe the root and root canal morphology of mandibular second molars in Western Guangxi by CBCT, to provide a reference for clinical diagnosis and treatment.@*Methods@#In total, 564 patients′ 1 128 mandibular second molars that satisfy the inclusion criteria were analyzed with a planmecaromexis CBCT machine and its own image analysis software. The patients′ gender, age and ethnic differences in the root and canal morphology and the symmetry of the bilateral root and canal were statistically analyzed. @*Results@# Among the 1 128 mandibular second molars, 662 were the Zhuang ethnic group and 384 were the Han ethnic group, and 82 were other ethnic groups; the double root type and C-shaped root type accounted for a relatively high proportion: 73.94% and 24.47%, respectively. The detection rates of the double root type were higher in males than in females (P < 0.05); the detection rates of the C-shaped root type were higher in females than in males (P <0.05); the root type of the teeth was mainly double-rooted in the Zhuang ethnic group (P<0.01). The incidence of type IV in the mesial root of the double root type mandibular second molar was the highest (P < 0.01), and the incidence of type I in the distal root was the highest (P < 0.01). The C-shaped root canal is more continuous at the mouth of the root canal, more downward corresponds to a worse continuity: in three different levels of root canal orifice, root middle and root apex, the root canal orifice is dominated by the C1 type, and both root middle and root apex are mainly C3-type (P < 0.01). The difference in symmetry of bilateral roots and root canals was statistically significant among different gender groups, age groups, and ethnic groups (P < 0.05): there were more males than females, the results in the 18-35-year-old group and the Zhuang ethnic group were higher.@*Conclusion@# The root and root canal morphology of mandibular second molars in western Guangxi people are complex and changeable. The roots are mainly double root type in the Han ethnic group and the Zhuang ethnic group. C-shaped roots are also common. The detection rate of C-shaped roots in the Zhuang ethnic group was higher, and the symmetry rate of bilateral roots and that of bilateral root canals was higher in the Zhuang ethnic group than in the Han ethnic group.