Private Practice in Orthodontics, Saskatoon, SK, Canada.
Department of Orthodontics, Hebrew University of Jerusalem, Hadassah Medical Center, Jerusalem, Israel.
Eur J Orthod. 2024 Jan 1;46(1). doi: 10.1093/ejo/cjad071.
To assess if the dental follicle volume of palatally impacted canines (PICs) affects the relative root position of the adjacent lateral incisors (LIs) and first premolars (FPs).
A retrospective cross-sectional study of 49 patients with unilaterally PICs with dental follicles who had CBCT imaging previously taken. Four orthodontic centers in different countries provided the sample. A mean difference of 5° between the angular measurements (mesiodistal tip, buccolingual inclination, or mesiodistal rotation) of the LI and FP adjacent to the PIC and the controls was considered clinically relevant. A value of 0.05 was set for significance level and a power of 80%. The minimum sample size was determined to be 26 patients. These patients were further assigned to an LI sample (n = 49) and an FP sample (n = 23), dependent on the direct contact of the dental follicle to that adjacent tooth. A manual segmentation technique was used to obtain the volumetric measurements of the dental follicle. Angular measurements of adjacent teeth were then compared to the contralateral nonimpacted side, which acted as the control. A multivariant regression analysis was performed using IBM SPSS software, and statistical significance was set at α = 0.05.
Adequate intra-rater reliability was accomplished. The multivariant regression analysis implied that there is no difference in the mean change in the tip, torque, and rotation of the LI and FP between the impacted and control sides when dental follicle volumes are considered (P = .509 for the LI sample and P = .804 for the FP sample).
CBCT imaging of dental follicle border delimitations, partial volume effect, and scattering are limitations. This is a convenience sample where the FP subsample is small.
The dental follicle volume of the PICs does not seem to influence the relative position of the adjacent LI and FP mesiodistal tip, buccolingual inclination, and mesiodistal rotation. Early intervention could have been suggested to avoid certain malocclusion traits if significant displacements were demonstrated.
评估腭侧埋伏尖牙(PICs)的牙囊体积是否会影响相邻侧切牙(LIs)和第一前磨牙(FPs)的相对根位置。
对 49 名单侧 PICs 伴牙囊的患者进行回顾性横断面研究,这些患者均有 CBCT 成像资料。4 个来自不同国家的正畸中心提供了样本。如果 LI 和 FP 与 PIC 相邻的角度测量值(近远中切端、颊舌倾斜或近远中旋转)之间存在 5°的平均差异,被认为具有临床意义。显著性水平设定为 0.05,功率为 80%。确定最小样本量为 26 例。这些患者进一步分为 LI 样本(n=49)和 FP 样本(n=23),取决于牙囊与相邻牙齿的直接接触。使用手动分割技术获得牙囊的容积测量值。然后将相邻牙齿的角度测量值与对侧未受影响的一侧进行比较,作为对照。使用 IBM SPSS 软件进行多变量回归分析,统计学显著性设置为 α=0.05。
实现了足够的内部评估者可靠性。多变量回归分析表明,当考虑牙囊体积时,LI 和 FP 的切端、转矩和旋转的平均变化在受影响侧和对照侧之间没有差异(LI 样本的 P=0.509,FP 样本的 P=0.804)。
CBCT 成像对牙囊边界的限制、部分体积效应和散射是局限性。这是一个方便的样本,FP 子样本较小。
PICs 的牙囊体积似乎不会影响相邻 LI 和 FP 的近远中切端、颊舌倾斜和近远中旋转的相对位置。如果显示出明显的移位,早期干预可能会被建议以避免某些错颌畸形特征。