Cleft lip (CL) and cleft palate (CP) are the most common congenital orofacial deformities. A combination of genetic predisposition and in-utero exposure to teratogens (nicotine, alcohol, antiepileptic drugs) can arrest the fusion of the facial processes required for normal facial development. Failure of fusion of the maxillary prominence with the medial nasal prominence causes cleft lip (CL). Failure of fusion of the palatine prominences causes cleft palate (CP). Cleft lip and/or palate may be unilateral or bilateral and complete or incomplete. In addition to facial deformity, infants with CL and CP have feeding, hearing, speech difficulties, and defects in the dentition. Infants with cleft lips and/or palate require special feeding techniques (feeding in upright position, special feeding bottles) since they cannot effectively create negative sucking pressure. Treatment should be initiated as early as possible and may involve an interdisciplinary team of plastic surgeons, oral maxillofacial surgeons, otolaryngologists, pediatricians, and speech therapists. Nasoalveolar molding and lip taping are non-surgical techniques used to decrease the size of the lip/palatal defects and should be initiated early (at 2 weeks of age). Repair of the cleft lip is done at 3 months of age and of the cleft palate at 6 months of age with the aim of optimizing feeding and speech development without interrupting normal maxillofacial growth.
- Unilateral CL/CP is more common than bilateral CL/CP
- Majority of cases are non-syndromic.
Epidemiological data refers to the US, unless otherwise specified.
The development of CL/CP is dependent on the interaction of environmental factors and genetic predisposition. 
- Genetic predisposition
- Environmental factors: exposure to teratogenic substances in utero
Cleft lip and palate involves a disrupted fusion of the 5 embryonic facial prominences (the midline frontonasal prominence, the bilateral maxillary prominences, and the bilateral mandibular prominences) and results in congenital orofacial deformities. 
- Cleft lip
- Cleft palate
Facial features 
CL/CP may be unilateral or bilateral, complete or incomplete.
- Microform cleft lip: slight, incomplete cleft characterized by a notch on the vermillion border of the upper lip (unilateral)
- Incomplete cleft lip: cleft on the upper lip that does not extend into the nostril (unilateral/bilateral)
- Complete cleft lip
- Unilateral cleft lip: the orbicularis oris inserts into the nasal ala on the cleft side and the columella on the unaffected side
- Bilateral cleft lip: the orbicularis oris inserts into the nasal alae bilaterally
- Incomplete cleft palate: clefting only of the secondary palate (anterior or posterior to the incisive foramen)
- Complete cleft palate
- Bifid uvula
- Submucosal cleft palate (occult cleft palate): muscular and/or bony palatal defect that is masked by intact palatine mucosa
Other features 
- Feeding difficulties: depends on the type and severity of the cleft
- Speech difficulties: hypernasal, unintelligible speech due to velopharyngeal insufficiency (a structural disorder that causes the inability to form a seal between the nasopharynx and oropharynx and that is characterized by hypernasal speech, which may impair intelligibility)
- Dentition defects (in CP): due to clefts creating gaps in the maxilla
- Hearing loss: due to recurrent/persistent otitis media with effusion (OME)
- Postnatal: clinical diagnosis; children with a submucosal cleft palate may present in later life with abnormal speech and/or OME
- Interdisciplinary management is required (oral maxillofacial surgeons. plastic surgeons otolaryngologists, pediatricians, and speech therapists)
- All cleft lips and palates should be surgically repaired.
- Speech assessment at 12–14 months and therapy of velopharyngeal insufficiency
Conservative measures before surgery 
- Proper feeding techniques: feeding in upright position to prevent nasal regurgitation; use of specialized feeding bottles ; frequent burping
- Nasoalveolar molding: Use of a custom made orthodontic prosthesis to bridge and reduce the palatal gap and passively mold the maxillary, palatal, and nasal structures into a normal shape
- Nasal stent: to lift the drooping nostril and shape the nose
- Lip taping: use of adhesive tape to reduce the defect; makes definitive surgery easier
- Lip adhesion: suturing the edges of the cleft lip, in conjunction with NAM can be done in infants with complete CL/CP who are not responding well to lip taping
Surgical repair 
Cleft lip repair (cheiloplasty)
- Goals: achieving normal lip contour and nose, improve oral competence
- Timing: at age 3 months, surgery is usually staged with cleft lip being the first surgery and cleft palate done at a later time due to risk of surgery to infant
- Tympanostomy tubes are placed at the same sitting: in children with OME causing hearing loss/recurrent infections
Cleft palate repair (palatoplasty) 
- Goals: closure of the defect, optimal speech development, and normal maxillofacial growth
- Timing: at age 6–9 months
- Further surgery is often required as the child grows older.