International Journal of Clinical Pediatric Dentistry

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VOLUME 10 , ISSUE 4 ( October-December, 2017 ) > List of Articles


Impacted Lower Second Permanent Molars at the Ramus and Coronoid Process: A New Clinical Symptom of the WNT10A Mutation in Ectodermal Dysplasia

Samia Aboujaoude

Citation Information : Aboujaoude S. Impacted Lower Second Permanent Molars at the Ramus and Coronoid Process: A New Clinical Symptom of the WNT10A Mutation in Ectodermal Dysplasia. Int J Clin Pediatr Dent 2017; 10 (4):363-368.

DOI: 10.5005/jp-journals-10005-1466

License: CC BY-NC 4.0

Published Online: 01-04-2016

Copyright Statement:  Copyright © 2017; The Author(s).



Hidrotic ectodermal dysplasia (ED) with the WNT10A mutation produces variable dentofacial symptoms. The aim of this study was to describe a new clinical symptom, i.e., specific to the WNT10A mutation in hidrotic ED. The study investigated the migratory trend of the lower second permanent molars to the ramus or coronoid process. To the best of authors' knowledge, no data in the literature describe this trend in cases of hidrotic ED.

Materials and methods

A three-generation family pedigree was established for seven families after the diagnosis of hidrotic ED in a 10-year-old boy. Thereafter, a genetic and clinical study was conducted on three families with at least one individual affected by hidrotic ED (20 individuals). We selected the children with molar germs 37 and 47. The eruption axes of these germs were then traced on the panoramic images at the initial time (T0) and 1 year later (T0 + 1 year), and the deviations between these axes were measured.


A significant familial consanguinity was shown. Eight subjects presented with the hidrotic ED phenotype. Among them, three individuals carried germs 37 and 47. Over time, the measured deviations between the eruption axes of the latter displayed, in the majority of the cases, a distal inclination toward the ramus.


A larger sample size is mandatory to assess the frequencies and treatment modalities.


The presence of germs in the lower second permanent molars in patients with hidrotic ED is an important clinical symptom that should be monitored to detect and prevent ectopic migration of these teeth.

Clinical significance

In hidrotic ED cases, the study of the presence of the second lower permanent germs must include clinical and radiological examinations. Establishing an interceptive treatment is necessary to prevent the migration of the molars in question.

How to cite this article

Sfeir E, Aboujaoude S. Impacted Lower Second Permanent Molars at the Ramus and Coronoid Process: A New Clinical Symptom of the WNT10A Mutation in Ectodermal Dysplasia. Int J Clin Pediatr Dent 2017;10(4):363-368.

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