Prevalence of Visible Third Molars in the United States Population: How Many Individuals Have Third Molars?

Abstract

Third molar prevalence did not appear to differ in the US population during the first decade of the 21st century. Numbers of visible third molars, prevalent in young adults, decreased progressively through each successive age cohort. Demographic differences exist for prevalence of third molars in the US population.

Prevalence of third molars determined by panoramic radiographs in a population‐based survey of adult Finns

“…We observed a similar prevalence for the presence of all four third molars per participant as found in the US study among 30‐ to 39‐year‐olds and 50‐ to 59‐year‐olds . This is surprising as our study was based on radiographs, and the US study used clinically visible numbers of third molars.…”

“…Furthermore, the prevalence of third molars is unique for each country and depends on factors such as ethnicity, health insurance system, access to health care and resources of healthcare personnel. For example, according to the US study, Caucasians have fewer visible third molars compared with African Americans …”

“…There are two detailed studies focused on the prevalence of third molars in the population . From these studies, the US survey is a nationally representative sample of the civilian and noninstitutionalized population in the 21st century covering ages from 20 to 80 years and over .…”

“…From these studies, the US survey is a nationally representative sample of the civilian and noninstitutionalized population in the 21st century covering ages from 20 to 80 years and over . The prevalence of clinically visible third molars is reported from a sample of approximately 4000 participants . The presence or absence of visible third molars is noted by dental hygienists in nonclinical settings.…”

Impacts of non‐impacted third molar removal on the periodontal condition of adjacent second molars

“…When age and M3s are considered together, there are several results that cannot be ignored. First, with increasing age, the risk and severity of diseases related to retained M3s increases (Kim, Jee, Song, Kim, & Kim, 2017), and most M3s, including N‐M3s, are removed during one's lifespan (Magraw, Moss, Fisher, Offenbacher, & White, 2016). Second, the prevalence of systemic diseases is higher in elderly individuals than in young individuals, leading to an increased risk of local and systemic complications in M3 extraction surgery (Baensch, Kriwalsky, Kleffmann, & Kunkel, 2017; Chuang, Perrott, Susarla, & Dodson, 2007).…”