Prevalence, distribution, and condition of persistent primary teeth in children and adolescents

Assessment of permanent teeth development in children with multiple persistent primary teeth

“…Considering the association between chronological age and dental age would be inconsistent in case of delayed eruption [9] and disturbances in dental development could lead to PPT and delayed tooth eruption, we found that there was a need to determine whether delayed eruption in children was due to PPT The local or systemic etiological factors of PPT may vary. The most common cause for PPT was reported to be agenesis of a permanent successor, while other factors might include the existence of a pathology (cysts, tumors and odontoma), impaction, transposition, and delayed eruption of successor teeth [4,15,21]. In addition, some systemic disturbances, syndromes and metabolic and hormonal disorders have also been reported to be associated with PPT [9,25].…”

“…Although the persistence of a single tooth may often occur, the occurrence of multiple PPT is rare. Only a limited number of publications on the PPT were found in the literature [4,15,16,26]. In a study conducted on a Turkish subpopulation of 9632 children aged 9-15 years, the prevalence of PPT was found to be 4.5%, in whom 92.6% of the patients had 1-3 PPT, 6.7% had 4-6 PPT, and 0.7% had >6 PPT [15].…”

“…Only a limited number of publications on the PPT were found in the literature [4,15,16,26]. In a study conducted on a Turkish subpopulation of 9632 children aged 9-15 years, the prevalence of PPT was found to be 4.5%, in whom 92.6% of the patients had 1-3 PPT, 6.7% had 4-6 PPT, and 0.7% had >6 PPT [15]. Multiple PPT and unerupted permanent teeth are usually associated with syndromes (Cleidocranial dysplasia, Gardner syndrome, Zimmerman Laband syndrome, Noonan's syndrome, Hyper-IgE syndrome) and conditions such as hemifacial atrophy, hypopituitarism, hypothyroidism, cherubism, gingival fibromatosis and cleft palate [27,28].…”

“…Willems modified the Demirjian method's scoring system by creating new tables [11], which was then used in studies comprising various populations and was reported to provide more accurate estimations than the original Demirjian method [13]. Willems method was also found appropriate for estimating the dental age of children from Eastern, Northwestern and Central Anatolia regions of Turkey [13][14][15]. Therefore, in this study, the Willems method was used for dental age estimation of children from the Aegean region of Turkey.…”

“…For estimating the required population size, based on the desired confidence interval of 95%, a margin of error of 5% and a 4.5% expected frequency of PPT, it was calculated that at least 67 children were needed to reach the study endpoint, as previously described [15]. Thus, by increasing the sample size by 20%, we included 80 children in each group.…”