Department of Orthodontics, College of Dentistry, The Institute of Craniofacial Deformity, Yonsei University, 50-1 Yonsei-Ro, Seodaemun-Gu, Seoul, 03722, Korea.
Department of Prosthodontics, College of Dentistry, Yonsei University, 50-1 Yonsei-Ro, Seodaemun-Gu, Seoul, 03722, Korea.
Clin Oral Investig. 2023 Jun;27(6):2609-2619. doi: 10.1007/s00784-022-04817-y. Epub 2022 Dec 20.
To evaluate changes in masticatory performance (MP) during the retention period after extraction and non-extraction treatment and compare it with MP in individuals with normal occlusion.
Adult patients who had completed orthodontic fixed appliance treatment comprised the extraction and non-extraction treatment groups, and those with normal occlusion comprised the control group. Their mixing ability (MA), maximum bite force (MBF), and occlusal contact area (OCA) were recorded immediately after the fixed appliance was removed and at 1 month, 6 months, and 1 year post-treatment. The MA was measured via the two-color chewing gum MA test using ViewGum software, and the MBF and OCA were measured using Dental Prescale II system.
MA immediately after orthodontic treatment was lower than that in the normal group but showed a time-dependent gradual increase during a 1-year retention period (P < 0.01). The MA at 1 month post-treatment was not significantly different between the three groups (P > 0.05). The MA revealed a significant correlation with the MBF and OCA (P < 0.01).
The MP immediately after orthodontic treatment was lower than that in the normal group but increased gradually, with levels comparable to those of the normal occlusion group at 1 month post-treatment. Further, extraction did not affect the recovery of the MP after orthodontic treatment.
No other study has evaluated the changes in MP during the retention period after orthodontic treatment. The findings show that compared with MBF and OCA, the patients' MP improved faster to levels found in normal occlusion.
评估拔牙和非拔牙治疗后保持期咀嚼效能（MP）的变化，并与正常合患者的 MP 进行比较。
完成正畸固定矫治的成年患者分为拔牙组和非拔牙组，正常合患者为对照组。在矫治器拆除后即刻、1 个月、6 个月和 1 年，记录其混合能力（MA）、最大咬合力（MBF）和咬合接触面积（OCA）。MA 通过 ViewGum 软件的双色口香糖 MA 试验测量，MBF 和 OCA 通过 Dental Prescale II 系统测量。
正畸治疗后即刻的 MA 低于正常组，但在 1 年保持期内呈时间依赖性逐渐增加（P<0.01）。治疗后 1 个月三组间 MA 无显著差异（P>0.05）。MA 与 MBF 和 OCA 呈显著相关（P<0.01）。
正畸治疗后即刻的 MP 低于正常组，但逐渐增加，治疗后 1 个月时与正常合组水平相当。此外，拔牙对正畸治疗后 MP 的恢复无影响。
尚无其他研究评估正畸治疗后保持期 MP 的变化。本研究结果表明，与 MBF 和 OCA 相比，患者的 MP 恢复更快，达到正常合水平。
