Non-syndromic orofacial clefts, including isolated cleft lip (CL), encompass a range of disorders involving the lips and oral cavity that negatively impact speech, hearing, appearance, and cognition, often requiring multidisciplinary care from birth until adulthood [1]. Based on pooled data from 57 registries worldwide, the prevalence of CL with or without cleft palate (CL/P) at birth ranged from 3.4 to 22.9 per 10,000 births, with an overall rate of 7.9 per 10,000 births [2]. This rate was not homogenous among registries (p < 0.001), with higher rates found in Asian (China, Japan) and South American (Bolivia, Paraguay) countries [2]. Others have estimated the overall global prevalence of orofacial clefting is 1 in 700 livebirths [1].

A separate, but related entity is the submucous cleft palate (SMCP). A classic SMCP is typically diagnosed by the presence of a (1) bifid uvula; (2) midline diastasis of the palatal muscles (zona pellucida); and (3) notching of the posterior border of the hard palate. An occult SMCP is diagnosed when there is diastasis of the palatal musculature without the remaining classical physical exam findings [3]. Although the prevalence rates of all forms of SMCP in the general population are reported between 0.02 and 0.08 %, the true prevalence of occult SMCP in the general population is unknown [3].

While multiple studies have demonstrated an association between an isolated CL and SMCP, the literature is less clear regarding a relationship between an isolated CL and chronic otitis media, or whether this combination of findings suggests the presence of an occult SMCP [[3], [4], [5],14]. Vallino et al. reported 28 % of children with isolated CL developed speech and/or language problems similar to that seen in children with a cleft-palate [6]. Smarius et al. concurred that isolated CL was associated with a greater need for speech therapy, but concluded that this did not increase the potential for acute otitis media or otitis media with effusion compared to the general population [7]. Others have suggested that alveolar involvement may increase the risk for palate related concerns, including the need for ventilation tubes [3,6,7]. Reviews by Deelder et al. and Rivelli et al. found 18–20 % of children with an isolated CL and/or alveolus (CL ± A) required ventilation tube insertion, which is higher than the rate typically reported in children without orofacial clefting (6.8 %) [6,[8], [9], [10]].

It has been hypothesized that middle ear dysfunction and associated speech deficiencies in this population may be related to an abnormal development of the soft palate musculature or an undiagnosed SMCP [8]. This study explored the prevalence of SMCP as well as timing of this diagnosis in children with an isolated CL and middle ear dysfunction.