Department of Orthodontics, Faculty of Dentistry, Bezmialem Vakif University, Istanbul, Turkey.
Department of Orthodontics, Faculty of Dentistry, Erciyes University, Kayseri, Turkey.
Eur J Orthod. 2019 Sep 21;41(5):544-550. doi: 10.1093/ejo/cjz010.
To assess dental root development in two groups of paediatric patients who received treatments with reverse headgear and rapid maxillary expansion and slow maxillary dental arch expansion.
The 20 subjects (13 girls, 7 boys; mean age: 8.9 ± 1.3 years) in the first group were treated with a Petit-type reverse headgear attached to a full-coverage bonded rapid maxillary expander via elastics (RME&RHg group). The 20 subjects included in the second group (9 girls, 11 boys; mean age: 9.1 ± 2.2 years) were selected among patients who were treated with Hawley appliances for slow maxillary expansion (SME group). Digitized panoramic radiographs were used. A total of 960 permanent teeth (maxillary-mandibular incisors, canines, premolars, and first molars) were measured quantitatively for pre-treatment and post-treatment.
No significant increase was found except for the right and left maxillary and mandibular second premolars and left mandibular and first premolar in the RME&RHg group (P < 0.05). Teeth length values increased significantly in all maxillary and mandibular teeth except maxillary first molars and mandibular incisors in the SME group (P < 0.05). Inter-group comparisons showed that statistically significant differences were observed in maxillary and mandibular incisors, left maxillary first premolar, and molar teeth (P > 0.05).
A limitation of this study is the use of two-dimensional radiographic images for root length measurement. However, ethical obligations limit the dental cone beam computed tomography imaging application for protection of paediatric patients from harm.
RME&RHg therapy inhibits root development of maxillary and mandibular teeth in the early period. However, further studies should be performed to determine whether this effect on root development is reversible or irreversible.
评估两组接受反向头帽和快速上颌扩张以及慢速上颌牙弓扩张治疗的儿科患者的牙根发育情况。
第一组 20 名患者(13 名女孩,7 名男孩;平均年龄:8.9 ± 1.3 岁)接受 Petit 型反向头帽通过弹性体连接全覆盖粘接快速上颌扩张器(RME&RHg 组)治疗。第二组包括 20 名患者(9 名女孩,11 名男孩;平均年龄:9.1 ± 2.2 岁),他们接受 Hawley 矫治器治疗上颌缓慢扩张(SME 组)。使用数字化全景片进行测量。对 960 颗恒齿(上颌-下颌切牙、尖牙、前磨牙和第一磨牙)进行定量测量,包括治疗前和治疗后的牙齿长度。
除了 RME&RHg 组的右侧和左侧上颌和下颌第二前磨牙以及左侧下颌和第一前磨牙外,其他牙齿长度没有明显增加(P < 0.05)。SME 组所有上颌和下颌牙齿的牙齿长度值均显著增加,除了上颌第一磨牙和下颌切牙(P < 0.05)。组间比较显示,上颌和下颌切牙、左侧上颌第一前磨牙和磨牙牙齿有统计学显著差异(P > 0.05)。
本研究的局限性在于使用二维射线影像来测量牙根长度。然而,伦理义务限制了牙科锥形束计算机断层扫描成像的应用,以保护儿科患者免受伤害。
RME&RHg 治疗早期抑制上颌和下颌牙齿的牙根发育。然而,应该进行进一步的研究,以确定这种对牙根发育的影响是可逆的还是不可逆的。