RESUMO
PURPOSE: The objective of this review is to present an update and summary of clinical findings of cases with a patent nasopalatine duct (NPD) reported in the literature from 1881 to 2016. METHODS: Previous articles and reviews about patent NPDs were studied and copies of all original publications were obtained for data verification. Furthermore, a literature search was conducted. In addition, the study sample was complemented with four cases recently seen in our institution. RESULTS: Ten out of 67 published cases were to be excluded for this analysis due to misinterpretation or misreporting in previous articles. Overall, 57 cases with NPD patency could be analyzed. Males outnumbered females in a ratio of 2:1. The mean age (when this information was available) was 34.1 ± 17.6 years (range 6-69 years). NPDs were located bilaterally (60%), unilaterally (20%) or centrally (20%). Complete or partial patency was reported in 73.9 and 26.1%, respectively. 74.1% of patients presented a variety of clinical signs and symptoms. The ability of the patient to produce a squeaky or whistling sound was the most frequent clinical finding (23.8%). CONCLUSIONS: Caution must be exercised when reading review articles about NPD patency since wrong data have been copied in several subsequent publications. Since epidemiological data are missing with regard to patent NPDs, age and gender predilections are not warranted. Bilateral occurrence and full patency were prevailing features in the evaluated case reports of patent NPDs.