Comparison Of Clinical Application Between The Preformed Metal Crown Space Maintainer And The Traditional Band-and-Loop Space Maintainer

Objective: To collect the children with the loss of the first primary molar in the clinical oral cavity,wear different space maintainers in groups,observe their clinical effects,and compare the change of the space,the rate of falling off of the space maintainer,the secondary caries of the abutment and adjacent teeth,the gingival index score,and the patient satisfaction,so as to provide theoretical reference for the future clinical selection of the space maintainer.Methods: 60 children aged 3-5 years were selected.Selection conditions:(1)The first deciduous molar is missing for half a month(2)The bilateral deciduous teeth in the gap are healthy or can be retained after treatment(3)The first molar is not erupted(4)X-ray shows that there is a tooth germ of the first premolar under the gap,and there is bone tissue above the tooth germ.60 children were randomly divided into ABC 3 group,group A was a blank control group,and 20 children did not have space maintainers;Group B was a group with Band-and-Loop space maintainer.20 children wore Band-and-Loop space maintainer after early loss of the first molar;Group C was a Preformed Metal Crown Space Maintainer group.20 children wore Preformed Metal Crown Space Maintainer after the early loss of the first molar.The three groups of children were revisited every 6 and 12 months.During each revisit,they were checked to see if there was any damage to the surrounding tissues in the children’s oral cavity,whether the retainer was loose or falling off,and the gap size was measured with a caliper.Results:(1)Space change: Single factor analysis of variance was used,and LSD(Least Significant Difference)method was used for comparison.Intra-group comparison: in the Band-and-Loop group,there was no significant difference in the gap before treatment,6months after treatment and 12 months after treatment(P>0.05),indicating that there was no change in the gap,and the effect of Band-and-Loop Space maintainer was significant;In the Preformed Metal Crown Maintainer group,there was no significant difference in the clearance before treatment,6 months after treatment and 12 months after treatment(P>0.05),indicating that there was no change in the clearance,and the effect of Preformed Metal Crown Space Maintainer was significant;In the blank group,there was a significant difference in the gap before treatment,6 months after treatment and 12 months after treatment(P<0.05),indicating that the space between the early loss of deciduous teeth and the early loss of deciduous teeth was significantly reduced in the children without space maintainer.Inter-group comparison: After 6 months and 12 months of treatment,there were significant differences(P<0.05)in the change of the space between the three groups,among which there was a significant difference between the blank group and the Band-and-Loop group(P<0.05),and there was a significant difference between the blank group and the Preformed Metal Crown Space Maintainer group(P<0.05).There was no significant difference between the Band-and-Loop group and the Preformed Metal Crown Space Maintainer group(P>0.05).It shows that after 6 and 12 months of treatment,there is no significant change in the gap size between the Band-and-Loop group and the Preformed Metal Crown Space Maintainer group,and the effect of the gap maintainer is significant;The gap in the blank group changed significantly and decreased significantly.(2)Chi-square test was used to compare the exfoliation rate between the Band-and-Loop group and the Preformed Metal Crown Space Maintainer group,P<0.05,the difference was statistically significant,indicating that the exfoliation rate of the Band-and-Loop group was higher than that of the Preformed Metal Crown Space Maintainer group.(3)Chi-square test was used to compare the secondary caries between the Band-and-Loop group and the Preformed Metal Crown Space Maintainer group,P<0.05,the difference was statistically significant,indicating that the incidence of secondary caries in the Band-and-Loop group was higher than that in the Preformed Metal Crown Space Maintainer group.(4)The scores of gingival index were compared by Chi-square test,P<0.05,and the difference was statistically significant,indicating that the score of gingival index in the Band-and-Loop group was higher than that in the Preformed Metal Crown Space Maintainer group.(5)Compared with the satisfaction of patients and their families,on the whole,the satisfaction of children and their families is relatively high.Compared with the Preformed Metal Crown Space Maintainer group,the children in the Band-and-Loop group had lower satisfaction than those in the Preformed Metal Crown Space Maintainer group due to different degrees of gap maintainer detachment and secondary caries.Conclusion: There is no significant difference between the Band-and-Loop group and the Preformed Metal Crown Space Maintainer group in space maintenance,and the treatment effect is better than that of the blank group.However,the Preformed Metal Crown Space Maintainer is better than the Band-and-Loop space maintainer in terms of the exfoliation rate,secondary caries,gingival index and patient satisfaction.