Department of Pediatric Dentistry, Faculty of Dentistry, Eskisehir Osmangazi Universitesi, Eskisehir, Turkey.
Int J Clin Pract. 2021 Mar;75(3):e13880. doi: 10.1111/ijcp.13880. Epub 2020 Dec 18.
The aim of this study was to describe the occurrence, angulation and mesialisation ratio of the ectopic eruption of the maxillary permanent first molar (PFM) and its correlation with the pathological resorption of maxillary primary second molar (PSM).
This retrospective study was performed using the subsequent panoramic radiographs of 11.924 child patients aged 6-10 years. Ectopic eruption status is categorised as self-corrected and impacted types. To evaluate the differences between the two groups (self-corrected and impacted), the angulation of PFM, mesialisation ratio of PFM, and degree of adjacent PSM root resorption were also assessed. The data were statistically analysed using ANOVA and chi-square tests. Pearson correlation was used to analyse whether a quantitative relationship exists between PFM mesialisation ratio and PSM root resorption.
Ectopic eruption frequency was determined as 0.83%. The distribution of ectopic eruption according to gender shows a higher prevalence in males than females. In most cases of ectopic eruption, the eruption status was impacted. The impacted PFMs showed more negative vertical and positive horizontal angle between the PSM and PFM. There was no significant difference between eruption status and angles. Mesialisation ratio of impacted PFMs was significantly higher than self-corrected PFMs. There was significant difference between the PFM mesialisation ratio and the degree of PSM root resorption.
Even if eruption disturbances do not occur frequently, making an early diagnosis is important to begin treatment at an optimal time. Although the relationship between horizontal and vertical angles and the ectopic eruption pattern is controversial, it is one of the clinical determinants. The mesialisation ratio of the impacted type was significantly higher than the self-corrected type. Self-correction of PFM was reduced in PSM with grade III and IV root resorption.
本研究旨在描述上颌恒磨牙（PFM）异位萌出的发生、倾斜角度和近中倾斜比率，以及其与上颌乳磨牙（PSM）病理性吸收的相关性。
本回顾性研究使用了 11924 名 6-10 岁儿童的后续全景片。异位萌出状态分为自行矫正和阻生两种类型。为了评估两组（自行矫正和阻生）之间的差异，还评估了 PFM 的倾斜角度、PFM 的近中倾斜比率以及相邻 PSM 牙根吸收的程度。使用方差分析和卡方检验对数据进行统计学分析。使用皮尔逊相关分析来分析 PFM 近中倾斜比率与 PSM 牙根吸收之间是否存在定量关系。
异位萌出的频率为 0.83%。根据性别分布，异位萌出在男性中比女性更常见。在大多数异位萌出的情况下，萌出状态为阻生。阻生的 PFM 与 PSM 之间的垂直角度更负，水平角度更正。萌出状态与角度之间没有显著差异。阻生 PFM 的近中倾斜比率明显高于自行矫正的 PFM。阻生 PFM 的近中倾斜比率与 PSM 牙根吸收的程度之间存在显著差异。
即使萌出干扰不常发生，早期诊断也很重要，以便在最佳时间开始治疗。虽然水平和垂直角度与异位萌出模式之间的关系存在争议，但它是临床决定因素之一。阻生型的近中倾斜比率明显高于自行矫正型。PSM 牙根吸收程度为 III 级和 IV 级时，PFM 的自行矫正减少。
