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Updated: Oct 4, 2026

Ultrasonographic Evaluation of Salivary Glands for Sjogren's Syndrome: Diagnostic and Monitoring Insights
Published on: October 13, 2023
Oligodontia is associated with extra-oral ectodermal symptoms and low whole salivary flow rates
H Nordgarden1, J L Jensen, K Storhaug
1Department of Oral Surgery and Oral Medicine, Faculty of Dentistry, University of Oslo, Norway. hildeno@odont.uio.no
Introduction:
Ectodermal dysplasias (EDs) involve abnormal development of hair, teeth, nails, and sweat glands.
Objectives:
(1) To investigate the frequency of extraoral ectodermal symptoms in persons with oligodontia (>6 congenitally missing teeth). (2) To examine whole salivary flow rates in oligodontia patients, with special emphasis on persons with EDs. SURVEY GROUP AND METHODS: Sixty-eight persons with oligodontia and 39 healthy control persons were included. All participants underwent an interview, general and oral examinations, and whole salivary secretory tests.
Results:
Thirty-nine (57%) of the oligodontia patients had disturbances in either hair, nails and/or sweat production in addition to teeth and were classified as the ED group. The remaining 29 oligodontia patients had no obvious signs of EDs (non-ED group). The prevalences of dry skin, asthma and eczema were higher, and whole salivary secretory rates lower, in the ED group as compared to the control group. Intermediate values were observed in the non-ED group. Incisors, canines and molars were more frequently missing in the ED group than in the non-ED group, whereas no differences were observed in the frequency of missing premolars. Negative correlations between the number of missing teeth and unstimulated and chewing stimulated whole salivary secretory rates were found.
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