Accuracy of progress assessment with clear aligners

doi:10.7518/hxkq.2022.06.011

Abstract

Abstract:

Objective This study aimed to investigate the accuracy of model superimposition and automatic analysis for upper and lower dentition widths in iTero Progress Assessment during the clear aligner process. Methods Nineteen cases were included in this retrospective case control study. Pretreatment dental cast (T0) and post treatment dental cast after staged treatment (T1) were available for three-dimensional (3D) model superimposition. The movements of maxillary teeth in the horizontal plane (cross section) after staged treatment and the widths of upper and lower dentitions were measured by 3D model superimposition in real world and iTero Progress Assessment. The data collected from the two methods were compared. Results The movements [Median (upper and lower quartiles)] of maxillary teeth in the horizontal plane after staged treatment were 2.31 (1.59, 3.22) and 1.79 (1.21, 3.03) mm in iTero Progress Assessment and 3D model analysis, respectively. Significant difference was observed between the two groups (P<0.05). In the measurement of upper and lower dentition width, four indicators were measured, including intercanine width upper, intermolar width upper, intercanine width lower, and intermolar width lower. Before treatment, the measurement of iTero Progress Assessment were (35.78±2.49), (56.21±2.51), (27.43±1.38), (52.26±2.91) mm, respectively, and actual measurement were (35.77±2.53), (56.17±2.47), (27.40±1.41), (52.30±2.86) mm, respectively, without significant difference (P>0.05). After stage treatment, the measurement of iTero Progress Assessment were (37.37±2.86), (57.76±2.56), (28.89±2.00), (54.16±2.19) mm, respectively, and actual measurement were (37.29±2.94), (57.71±2.63), (28.88±2.05), (54.01±2.15) mm, respectively, and there was no significant difference (P>0.05). Conclusion The data from iTero Progress Assessment did not coincide with the model superimposition results with palate as reference. The accuracy of model superimposition in iTero Progress Assessment needs further investigation, whereas the arch width analysis is accurate. Therefore, iTero Progress Assessment results should be interpreted with caution by orthodontists in clinical applications.

Key words: clear aligner, three-dimensional model superimposition, progress assessment, model analysis

CLC Number:

R 783.5

Li Bo, Xu Yimeng, Shi Ruiying, Hu Yirong, Liu Siying, Gu Zexu.. Accuracy of progress assessment with clear aligners[J]. West China Journal of Stomatology, 2022, 40(6): 698-703.

Figures/Tables 5

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牙列分析指标	初诊					阶段治疗后
牙列分析指标	样本量	iTero组	AM组	t值	P值	样本量	iTero组	AM组	t值	P值
上颌尖牙间宽度/mm	17	35.78±2.49	35.77±2.53	0.28	0.79	18	37.37±2.86	37.29±2.94	1.14	0.27
上颌磨牙间宽度/mm	19	56.21±2.51	56.17±2.47	1.00	0.33	19	57.76±2.56	57.71±2.63	0.64	0.53
下颌尖牙间宽度/mm	19	27.43±1.38	27.40±1.41	0.55	0.59	19	28.89±2.00	28.88±2.05	0.33	0.74
下颌磨牙间宽度/mm	19	52.26±2.91	52.30±2.86	-1.15	0.27	19	54.16±2.19	54.01±2.15	1.76	0.09

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