The Effect Of Different Thickness Of Relieves Of Custom Tray On The Restoration Of Edentulous Mandibular Denture

Objective:Aiming at the problem of highly readmission rate of clinical patients with complete denture,the influence of the thickness of relief space of custom trays on the accuracy of edentulous mandibular impression was studied,and the restoration effect was evaluated to provide guidance for the reduction of clinical readmission rate.Methods:Patients who were diagnosed in the Department of Stomatology of Shanxi Medical University due to missing mandibular dentition were selected.For 45 patients with Defective dentition,after signing of the informed consent,randomly divided into A,B,C three groups,making custom trays according to no relief,thickness of the relief of 1.5 mm,and 2 mm respectively,then the final impression mold is prepared.through 3 shape digital impression scanning to obtain the final impression in patients with three-dimensional model and standard impression finally evaluate,which is the impression of grinding pressure point,and with the application of reverse engineering software geomagic(studio2013),two impression image datas will be to carry on the registration,Then the 3D deviation of the registration image was analyzed.The data were processed by SPSS software,and P<0.05 was considered statistically significant.Results:1.The three custom trays from the final impression compared with standard impression,the deviation value between groups was statistically difference(P = 0.000), shows that deviation between ABC three groups of averages are not all equal,continue to do between two groups to compare(as shown in table 2),according to the results in group A and group B(P = 0.000),group A and group C(P = 0.000),group C and group B(P = 0.016),were statistically significant,deviation in the three groups show from low to high group B(smallest),group C(largest).2.Appointment times compare with Kruskal Wallis H-testing,the results as shown in table 3: P = 0.01 < 0.05,suggesting that three groups was statistically difference between appointment times,on the appointment times > group A group B,group C mucosa tenderness parts compared with chi-square test,pressure parts of the comparison between three groups was statistically difference(P(27)0.05),the edge sealing area tenderness rate is highest,tenderness rate from high to low for A(61.7%)> C(48.5%)>B(48%).Conclusion:1.When the final impression is made of silicone rubber,the tissue surface and mucosal morphology of the final denture are more suitable for the reserved space of individual trays(1.5mm).2.The reserved space of individual trays(1.5mm)produced the less number of denture reexamination and pain site.