Congenitally missing second permanent molars in non‑syndromic patients (Review)

Farcașiu,Alexandru-Titus; Luca,Rodica; Didilescu,Andreea; Stanciu,Ioana-Andreea; Farcasiu,Catalina; Vinereanu,Arina; Munteanu,Aneta

doi:10.3892/etm.2021.11068

Congenitally missing second permanent molars in non‑syndromic patients (Review)

Authors:
- Alexandru-Titus Farcașiu
- Rodica Luca
- Andreea Didilescu
- Ioana-Andreea Stanciu
- Catalina Farcasiu
- Arina Vinereanu
- Aneta Munteanu
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Affiliations: Department of Removable Prosthodontics, Faculty of Dental Medicine, ‘Carol Davila’ University of Medicine and Pharmacy, Bucharest 032799, Romania, Department of Pedodontics, Faculty of Dental Medicine, ‘Carol Davila’ University of Medicine and Pharmacy, Bucharest 032799, Romania, Department of Embryology, Faculty of Dental Medicine, ‘Carol Davila’ University of Medicine and Pharmacy, Bucharest 032799, Romania
Published online on: December 15, 2021 https://doi.org/10.3892/etm.2021.11068
Article Number: 145
Copyright: © Farcașiu et al. This is an open access article distributed under the terms of Creative Commons Attribution License.

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Abstract

Hypodontia (tooth agenesis) is regarded as the most common congenital dental anomaly. The present review discusses the epidemiological characteristics of congenitally missing second permanent molars (CMSPMs) within a systematic review of the literature. The review was based on Pubmed library associated with the search of various scientific databases or academic resources, improved by hand search of reference lists. The terms ‘hypodontia’ or ‘anodontia’ in combination with ‘prevalence’ or ‘epidemiology’ were searched in the data sources for studies published between January 2001 and December 2020. Abstracts of non‑English papers were also analyzed. The inclusion criteria were as follows: i) Study provided precise data about CMSPMs, even if no second permanent molar was reportedly missing; ii) the number of CMSPMs distributed by jaw was provided and iii) studies on subjects >3 years were used. The exclusion criteria were as follows: i) Studies on patients with history of trauma of the maxilla or the mandible, any type of syndrome affecting bone metabolism, metabolic disorders, previous extraction or tooth loss due to dental caries, cleft lip and palate; ii) studies performed on cohorts of patients with hypodontia and iii) studies reporting data including third molars, except for those that presented sufficient data to perform correct calculations. A total of 79 studies were selected, accumulating a population of 281,968 people, with an average sample size of 3,524.60±11,255.25. The prevalence of CMSPMs (IpHSPM) was 2.79±3.16% among all missing teeth (1.03±1.59% for upper CMSPMs and 1.76±2.32% for lower CMSPMs; P=0.011). There were no significant differences (P=0.250) in IpHSPM between men (1.59±1.52%) and women (2.13±1.67%). However, significant differences were recorded between continents. Furthermore, lower CMSPMs were found more frequently in orthodontic samples (P=0.033). The prevalence of CMSPMs is low compared with the overall prevalence of CM teeth. Despite the rarity of these anomalies, early detection is important to enable practitioners to plan and start treatment at the best time for optimal results.

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