Which type of cleft is visibly open and can be observed on intraoral inspection?

An overt cleft is visibly open and can be directly observed during an intraoral inspection. This type of cleft results in a physical separation in the lip, the hard palate, or both, allowing for clear visualization of the cleft in the oral cavity. The cleft can be classified based on its location and severity, and it manifests as a noticeable gap or split, which makes it identifiable during a standard examination.

In contrast, submucous cleft palate is not always visible because the mucous membrane remains intact, effectively hiding the underlying cleft in the muscle and bone. Similarly, an occult submucous cleft palate may also be present without external signs, as it involves clefting that is not apparent on the surface. Zona pellucida is a term that does not pertain to clefts in the context of speech-language pathology but refers to a structure related to egg cells in reproductive biology. This all highlights the distinct characteristics that make an overt cleft easily observable during an examination.