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Updated: Jul 24, 2025

Author Spotlight: 3D Movement Assessment of Maxillary Posterior Teeth in Clear Aligner Treatment
Published on: February 23, 2024
Prevalence and local causes for retention of primary teeth and the associated delayed permanent tooth eruption
Suelyn Danielle Henklein1, Erika Calvano Küchler2,3, Peter Proff2
1Department of Biomaterials, University of Uberaba, Uberaba, Minas Gerais, Brazil.
Background:
This study aimed to evaluate the prevalence of retained primary teeth (RPT) associated with delayed permanent tooth eruption and the factors associated with this condition in German children.
Methods:
This is a cross-sectional retrospective study that evaluated panoramic radiographs from orthodontic patients. The diagnosis of RPT was established according to Nolla developmental stage. The primary tooth was considered retained when its successor permanent tooth was in Nolla stage 8, 9, or 10. Statistical analysis was performed with an α of 5% (p < 0.05).
Results:
A total of 102 children (48 girls and 54 boys), and 574 primary teeth and their respective permanent successor teeth were evaluated. We classified 192 teeth as RPT. Sixty-one (59.8%) children presented one or more RPT. Gender was not significantly different between RPT and control teeth (p = 0.838; odds ratio 0.95, confidence interval 95% 0.44-2.16). In the majority of the RPT cases (68.7%), no clear cause to explain the prolonged retention was identified. The pathological problems most commonly observed with RPT were dental fillings (19.3%), followed by dental caries (4.6%), and ectopic tooth eruption (2.1%).
Conclusions:
The incidence of RPT associated with delayed permanent tooth eruption in German children was high and the most common pathological condition associated with RPT was dental caries.
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