ABSTRACT
Objective:To evaluate the effect of semiconductor lasers irradiation after routine root canal preparation on root cannal seal.Methods:60 Single-rooted freshly extracted human teeth were randomly divided into 6 groups(n=10).The crowns were removed at the cementoenamel junction and the roots were endodontically prepared with conventional methods.The roots in groups A and B were irradiated with 1 W semiconductor laser for 20 s,in group C and D were ultrasonically washed for 1 min,in group E and F without any treatment were used as the controls.Then all the roots were filled by vertical condensation of warm gutta-percha.The root cannal seal was evaluated with microleakage measurement.The data was analyzed by ANOVA.The teeth of group B,D and F were sectioned and examined under scanning electron microscope(SEM).Results:The microleakage(mm) of group A,C and E was 1.70±0.82,2.02±0.40 and 4.56±2.72 respectively(A vs E,P0.05).SEM observation showed the melting,narrowness or closure of most dentinal tubules in group B,past and/or gutta-percha in the most dentinal tubules of group D.Conclusion:Semiconductor laser irradiation prior to root cannal filling can promote the effects of cannal seal.
ABSTRACT
BACKGROUND: It can to a certain extent prevent complications during root canal preparation and improve the success rate of root canal therapy by understanding root canal anatomical configuration and bending degree.OBJECTIVE: To investigate the root canal curvature of permanent anterior teeth from Han Chinese people in Shandong province.METHODS: A total of 208 anterior teeth were collected and examined by indirect digital X-ray radiography both from labiolingual and mesiodistal directions,according to Schneider method,the data obtained were analyzed.RESULTS AND CONCLUSION: Most root canals of anterior teeth from Shandong province were typeⅠ,and more than half were curved. The most curvature happened in the apical third. The highest rate of canal curvature occurred in maxillary canines. Except the central incisors,the S-shaped canal was observed on the rest teeth. The radius of mandibular anteriors was obvious longer in labiolingual directions than that in mesiodistal directions. Root canal curvatures of anterior teeth from Shandong province are complex and have a higher bending rate.
ABSTRACT
Objective To explore the effect of antidepressant intervention on mood state of at or around the time of radiation therapy. Methods 62 hospitalized patients with cancer receiving radiotherapy were divided into two groups by the order of the time when they accept the radiotherapy which called intervention group ( antidepressant fluoxetine group) and control group. And the two groups patients filled out Hamilton Anxiety Scale( HAMA )and Hamilton Depression Scale (HAMD) at or around the time of radiation therapy to investigate the effects of fluoxetine on anxiety and depression. Results The scores of HAMA and HAMD showed that there was no differences between the intervention group and the control group before the radiotherapy. There was significant difference during the radiotherapy ( 6.41 ± 2.30 ) vs ( 9.29 ± 5.62 ); ( 8.80 ± 3. 048 ) vs ( 12.22 ± 8.32 ) and two weeks after the end of the radiotherapy ( 4.90 ± 1.71 ) vs ( 12.32 ± 7.24 ); ( 6.83 ± 2.47 ) vs ( 16.09 ± 8.61 ) between antidepressant fluoxetine group and control group(P ＜ 0.05 ). Conclusion More attention should be paid to mental health and antidepressant can alleviate anxiety and depression of the cancer patients'at or around the time of radiotherapy.