Heterogeneity of Orodental Features in a Family with Noonan Syndrome

Noonan syndrome is a relatively common genetic syndrome with clinical and genetic heterogeneity. Besides the characteristic features such as short stature, typical facial features, congenital heart defects, skeletal and ocular anomalies, various orodental manifestations occur with variable frequency. High-arched palate, malocclusions, micrognathism, giant cell lesions, and anomalous lateral incisors are frequently observed features, whereas supernumerary teeth, hypodontia, macrodontia, enamel hypoplasia, severe dental caries, impacted teeth, delayed eruption, taurodontism and odontoma have occasionally been reported. Here, we present a family with three affected members displaying variable dental manifestations carrying the same PTPN11 c.178G>A pathogenic variant. A 14-year-old and a 12-year-old, both female patients, presented high-arched palates, delayed dental eruption and caries. Moreover, the younger sibling exhibited frequently observed manifestations such as malocclusion and gingivitis, and further rare features like open-bite, micrognathia, and crowded teeth were present. The mother of the patients had periodontitis and enamel problems. Monitoring the oral health of the patients with NS is important, as they are prone to severe dental caries, gingival and other orodental problems. Therefore, initiating early orodental examination is highly recommended for patients with suspicion or diagnosis of NS.