CLEFT LIP AND CLEFT PALATE
Cleft lip and cleft palate (CLP) are two distinct but closely related developmental malformations of oral cavity with impaired development or fusion of facial processes.
Embryology: Normally, the lip and alveolus develop by fusion of maxillary and medial nasal processes, while palate develops by fusion of two palatal halves in midline.
Thus, Cleft lip represents absence of fusion between medial nasal process with maxillary process, while cleft palate indicates failure of two palatal shelves to approximate or fuse.Incidence of cleft lip with/without palate and cleft palate alone is ~ 1:1000 and ~1:2000 children respectively, former being more common in males. Isolated cleft palate is more common than isolated cleft lip (40% vs 15%), while ~45% cases have combined defect.
Fig. 14.3: Cleft lip (A) and cleft palate (B).
Cleft lip is usually an isolated defect, while cleft palate may be either alone or with other congenital malformations, e.g. first branchial arch defects or chromosomal abnormalities.
Etiology of CLP is multifactorial with a genetic basis and environmental factors, e.g. maternal smoking or alcohol/ drug consumption. Familial tendencies are known, with recurrence risk of ~3-4% and ~10-15% in siblings and offsprings of the index case, respectively. Many genetic mutations have been identified associated with CLP, e.g. TGFA, TGF-133, etc.
Clinically, cleft lip may be unilateral or bilateral, varying from being a small notch in vermillion border to complete separation extending up to nasal floor. Cleft palate may involve uvula, soft and hard palate or even combine with cleft lip to expose one or both nasal cavities (Fig. 14.3).
Functionally, cleft lip alone is a cosmetic abnormality, while cleft palate can adversely affect various facial functions e.g,
• Feeding difficulties, due to inability to create sufficient negative pressure for sucking.
• Recurrent aspiration and respiratory infections
• Deafness, due to eustachian tube dysfunction and recurrent otitis media.
• Dental malocclusion and caries.
• Speech defects, due to misarticulation, hyper/ hyponasality and nasal escape.
Management of CLP is a team-work involving surgeon, dentist, pediatrician and speech therapist. Treatment of cleft lip is mainly surgical, while cleft palate requires special medical care till repaired.
Medical management of cleft palate includes:
• Feeding: While many babies with cleft palate can suck effectively, it is preferable to feed them expressed breast milk via a bondla or spoon to obviate the need of sucking and in propped-up position to prevent aspiration. Obturators may be useful to allow direct breastfeeding in smaller clefts.
• Speech often remains impaired till surgery, but subsequently normal speech may be attained after surgery by speech therapy.
• Dental malocclusion requires post-operative orthodontic correction. Normal jaw growth and dental occlusion may remain subnormal even after surgery, due to abnormal compression of the repaired lip, inherent bony deficiency and scar contracture.
• Hearing is commonly impaired due to recurrent otitis media and hence, early treatment of these cases is critical to retain hearing and later speech.
Surgical management aims to aesthetically reconstruct the defect, to obtain adequate speech and feeding functions, and to encourage adequate growth of facial skeleton. Just after birth, pre-surgical orthodontics/ nasoalveolar molding may be given to reduce the width of the cleft, correct the depression of the alar base and improve alveolar alignment.
• Cleft lip is usually operated at 3-6 months (Rule of 10- age: 10 weeks; Weight: 10 lb; Hb: 10 gm) with Z-plasty, though revision surgery may be needed at 5-6 years and rhinoplasty during adolescence.
• Cleft palate is usually operated at 9-12 months to allow normal speech development, though timing has to be individualized according to the size of defect.
Good post-operative care is critical for surgical success, as wound infection with re-opening of defect and aspiration are common post-operative complications.Some other important orofacial malformations are as follows:
Pierre-Robin syndrome is an important orofacial malformation with mandibular hypoplasia, characterized by a triad of—(a) micrognathia/retrognathia, (b) macroglossia, and (c) glossoptosis. These cases must be managed in prone position to prevent posterior displacement of the tongue that may obstruct airways. Severe cases may require suturing of the tongue with alveolar margins and/or tracheostomy, till mandibular growth is adequate.
Treacher Collins syndrome (Mandibulo-facial dysostosis) is a rare facial dysmorphism, with triangular face, receding chin, blind fistulas between ears and angle of mouth, downward slant of eyes, coloboma of eyelids and ear abnormalities with/without deafness.
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