Synodontism involving both primary and permanent teeth in a mixed dentition case

Abstract

Fusion is a sort of developmental alteration due to the union of 2 adjacent tooth buds. It can be either partial or complete fusion, depending on the stage of tooth development. It can occur in either deciduous or permanent dentition. Here, we report a rare case of fusion in both deciduous and permanent teeth that are in between deciduous maxillary central and lateral incisors and in between permanent mandibular central and lateral incisors in a 10-year-old boy.

The first archaeological case of permanent teeth fusion in Europe

“…Clinical cases of double teeth are often described in the modern literature (Castelino et al, 2015; Guimarães Cabral et al, 2008; Kavya et al, 2019; Neves et al, 2002; Sekerci et al, 2011; Tomizawa et al, 2002; Wu et al, 2019), but this anomaly was not recorded in the permanent dentition of past European populations until now. The only documented ancient case involving permanent dentition concerns a 4,000 years old Egyptian mummy with upper incisors fusion (Forshaw, 2019).…”

“…Each dental crown has its own pulp chamber, which seems to be separated and independent. This could mean that the fusion process occurred during the later stage of morph differentiation (Kavya et al, 2019; Mehta, 2019). Two unconnected roots depart near the cement enamel junction, and each root appears to have a single endodontic canal system.…”

“…The aetiology is usually searched in congenital, inherited, acquired or idiopathic factors (Kavya et al, 2019). However, other factors may give origin to the double teeth, such as thalidomide embryopathy, hypervitaminosis, fetal alcohol exposure or syndromes such as trisomy 21, orodigitofacial syndrome and Pierre–Robin syndrome (Kavya et al, 2019).…”

“…Nowadays, double teeth occur with a frequency ratio between 0.1% and 1% in permanent dentition and 0.5% and 2.5% in primary dentition (Castelino et al, 2015; Wu et al, 2019). This defect has an equal distribution between males and females, and it seems to highly spread among Asian and South American population compared to Caucasian one (Kavya et al, 2019). It is very rare for this defect to bilaterally occur (Tomizawa et al, 2002).…”

“…It is very rare for this defect to bilaterally occur (Tomizawa et al, 2002). Caries or calculus formation can be related due to the presence of deep grooves (Kavya et al, 2019).…”