Carrillo Jorge J Pavani, Rubial Maria C, Albornoz Cristina, Villalba Silvina, Damiani Patricia, de Cravero Marta Rugani
Faculty of Dentistry, National University of Córdoba, Cordoba, Argentina.
Open Dent J. 2017 Apr 26;11:213-220. doi: 10.2174/1874210601711010213. eCollection 2017.
The Moyers' probability tables are used in mixed dentition analysis to estimate the extent of space required for the alignment of canines and premolars, by correlating the mesiodistal size of lower incisors with the size of permanent canines and premolars.
This study intended to evaluate the applicability of the Moyer's probability tables for predicting the mesiodistal space needed for the correct location of premolars and permanent canines non-erupted, in adolescents of the city of Cordoba, Argentina, who show different facial biotypes.
Models and tele-radiographies of 478 adolescents of both genders from 10 to 15 years of age were analyzed. The tele-radiographies were measured manually in order to determine the facial biotype. The models were scanned with a gauged scanner (HP 3670) and measured by using Image Pro Plus 4.5 software.
According to this study, the comparison between the Moyer´s probability table, and the table created at the National University of Córdoba (UNC) (at 95%, 75%, and 50%) shows that, in both tables, a higher value of mesiodistal width of lower incisors corresponds to a bigger difference in the space needed for permanent canines and premolars; being the need for space for permanents canines and premolars bigger in the UNC´s table. On the other hand, when contrasting the values of mesiodistal space for permanent canines and premolars associated with each facial biotype, the discrepancies between groups were not statistically significant ( >0.05). However, we found differences in the size of the space required according to the mesiodistal width range of the lower incisors for each biotype: a) The comparison of lower-range values, with a mesialdistal width of lower incisors less than 22 mm, the space required for permanent canines and premolars resulted smaller in patients with dolichofacial biotype than in patients with mesofacial and braquifacial biotypes. The latter biotypes have meager differences between them. b) The comparison of mid-range values, with a mesialdistal width of lower incisors from 22 to 25 millimeters, shows that the values of required alignment space are similar in the three facial biotypes. c) Finally, the comparison of upper range values, with a mesialdistal width of lower incisors greater than 25 millimeters, indicates that the space required for dolichofacial biotypes tends to be higher than in mesofacial and brachyfacial biotypes.
The Moyer´s probability tables should be created to meet the needs of the population under study, with no consideration of patients' facial biotypes.
莫耶斯概率表用于混合牙列分析，通过将下切牙的近远中尺寸与恒牙尖牙和前磨牙的尺寸相关联，来估计尖牙和前磨牙排齐所需的间隙大小。
本研究旨在评估莫耶斯概率表在预测阿根廷科尔多瓦市不同面部生物型的青少年未萌出的前磨牙和恒牙尖牙正确定位所需的近远中间隙方面的适用性。
分析了478名10至15岁青少年的模型和远中曲面断层片。手动测量远中曲面断层片以确定面部生物型。使用校准扫描仪（惠普3670）对模型进行扫描，并使用Image Pro Plus 4.5软件进行测量。
根据本研究，将莫耶斯概率表与科尔多瓦国立大学（UNC）创建的表格（95%、75%和50%）进行比较，结果显示，在两个表格中，下切牙近远中宽度值越高，恒牙尖牙和前磨牙所需间隙的差异越大；UNC表格中恒牙尖牙和前磨牙所需的间隙更大。另一方面，当对比与每种面部生物型相关的恒牙尖牙和前磨牙近远中间隙值时，组间差异无统计学意义（>0.05）。然而，我们发现根据每种生物型下切牙近远中宽度范围所需间隙大小存在差异：a）比较下限值，下切牙近远中宽度小于22毫米时，长面型生物型患者的恒牙尖牙和前磨牙所需间隙小于中面型和短面型生物型患者。后两种生物型之间差异不大。b）比较中间值，下切牙近远中宽度为22至25毫米时，三种面部生物型的所需排齐间隙值相似。c）最后，比较上限值，下切牙近远中宽度大于25毫米时，长面型生物型所需间隙往往高于中面型和短面型生物型。
应创建符合所研究人群需求的莫耶斯概率表，而不考虑患者的面部生物型。
