Cleft Lip: Symptoms, Types, Causes and Treatment

Cleft lip is among the most prevalent congenital craniofacial anomalies worldwide, affecting not only the physical appearance but also the overall health and quality of life of those born with it. This article delves into the symptoms, classification, underlying causes, and modern treatment approaches for cleft lip, drawing on the latest research to provide a comprehensive and human-centered overview.

Symptoms of Cleft Lip

Cleft lip presents with a spectrum of symptoms that can vary in severity and impact. Early recognition and understanding of these symptoms are crucial for timely intervention and optimal outcomes for affected children and their families.

Symptom	Description	Impact/Consequences	Source(s)
Visible Split	Gap or notch in the upper lip	Cosmetic, feeding, speech issues	3, 11
Nasal Deformity	Distorted shape of the nose	Breathing, aesthetics	3
Feeding Issues	Difficulty sucking or swallowing	Poor nutrition, failure to thrive	1, 11
Dysphagia	Coughing, choking, nasal regurgitation	Risk of aspiration, discomfort	1, 11
Dental Anomalies	Missing or malformed teeth	Chewing, speech, dental health	4, 5, 11
Speech Difficulties	Hypernasality, articulation problems	Communication challenges	11
Psychosocial Impact	Emotional and social challenges	Self-esteem, social integration	6, 11

Table 1: Key Symptoms of Cleft Lip

Physical Signs and Feeding Challenges

The most immediate and visible sign of a cleft lip is a gap or notch in the upper lip, which can range from a subtle notch to a complete split extending up toward the nose. This separation can be incomplete (partial) or complete, sometimes distorting the shape of the nostril and affecting the nose’s appearance as well 3. In newborns, this can lead to significant feeding challenges, including difficulty creating the necessary suction for breastfeeding or bottle-feeding, resulting in poor weight gain or malnutrition if not addressed promptly 1 11.

Dysphagia and Nasal Escape

Children with cleft lip, especially when accompanied by cleft palate, may experience dysphagia—difficulty swallowing food or liquids. Parents often report symptoms such as coughing, choking, nasal regurgitation (food or liquid coming out through the nose), and sometimes vomiting during feeding. Encouragingly, studies show that timely surgical correction can significantly reduce or eliminate these symptoms 1.

Dental and Speech Development Issues

Cleft lip can also be associated with dental anomalies, such as missing, malformed, or extra teeth, particularly affecting the lateral incisors adjacent to the cleft. These dental issues can further complicate feeding and speech development 4 5. Speech difficulties, including hypernasality and articulation problems, may arise if the cleft extends into the palate or affects the surrounding oral structures 11.

Psychosocial Effects

Beyond physical health, children and adolescents with cleft lip may face emotional and social challenges. They may experience self-esteem issues, negative social interactions, or even bullying, making psychological support an important aspect of care 6 11. However, some studies suggest that the type of cleft may not significantly influence the overall health-related quality of life in adolescence, highlighting the importance of holistic, individualized care 6.

Types of Cleft Lip

Cleft lip is not a one-size-fits-all condition. Understanding its various forms is essential for diagnosis, treatment planning, and patient support. The classification is based on anatomical location, extent, and whether the palate is involved.

Type	Description	Prevalence/Key Features	Source(s)
Unilateral Cleft Lip	Split on one side of the lip (right/left)	Most common, often left-sided	2, 3, 11
Bilateral Cleft Lip	Splits on both sides of the lip	Less common, more severe	2, 3, 11
Complete Cleft Lip	Split extends into the nose	May distort nose, more dental impact	3, 4
Incomplete Cleft Lip	Notch/cleft does not reach the nose	Milder, less nasal involvement	3, 11
Cleft Lip with Palate	Cleft lip plus split in palate	Functional, speech, feeding impacted	2, 11
Isolated Cleft Palate	Only palate involved, lip intact	More common in females	2, 11
Median Cleft	Midline split (very rare)	Minimal prevalence, unique traits	2

Table 2: Types of Cleft Lip

Unilateral vs. Bilateral Cleft Lip

A cleft lip can affect one side (unilateral) or both sides (bilateral) of the upper lip. Unilateral clefts are significantly more common, with a higher incidence on the left side. Bilateral clefts, involving both sides of the lip, are less frequent but often more severe, sometimes leading to greater nasal deformation and feeding challenges 2 3 11.

Complete vs. Incomplete Cleft Lip

The extent of the cleft also varies:

• Complete cleft lip: The separation runs the full height of the lip and extends into the nostril, frequently affecting the nasal structure and adjacent teeth. This type often results in more pronounced dental anomalies, particularly missing lateral incisors on the affected side 3 4.
• Incomplete cleft lip: The split does not reach the nostril, presenting as a notch or partial separation. These cases typically have less impact on nasal shape and function 3 11.

Associated Clefts: Cleft Lip with/without Palate

Cleft lip may occur alone or together with a cleft palate (the roof of the mouth). When both are present—referred to as cleft lip and palate—the likelihood of feeding, speech, and dental problems increases. Isolated cleft palate (without lip involvement) is more common in females, whereas cleft lip (with or without palate involvement) is more common in males 2 11.

Rare Types: Median Cleft

Median cleft lip is a rare form where the split occurs in the center of the upper lip. It accounts for a minor fraction of all clefts and often presents unique anatomical and dental considerations 2.

Dental Characteristics by Type

Different types of cleft lip and palate are associated with varying dental anomalies. For example, bilateral cleft lip and palate show the highest frequency and severity of altered dental characteristics, such as missing lateral incisors, compared to unilateral cases or isolated cleft lip 4 5.

Causes of Cleft Lip

The origins of cleft lip are multifactorial, involving a complex interplay between genetic predispositions and environmental influences. This section unpacks the known and emerging factors behind cleft lip development.

Cause Type	Examples / Details	Relative Contribution	Source(s)
Genetic Factors	IRF6, MSX1, TBX22, PVRL1 gene variants	Major in syndromic forms	8, 9, 10
Environmental	Maternal smoking, alcohol, poor nutrition, drugs	Significant, modifiable	7, 9, 10
Gene-Environment	Interaction between genes and exposures	Complex, under study	7, 8, 10
Syndromic	Van der Woude, Ectodermal Dysplasia, others	Minority of cases	8, 9, 10
Nonsyndromic	Isolated cases, no other anomalies	Majority, multifactorial	7, 8, 9

Table 3: Causes of Cleft Lip

Genetic Factors

Genetics play a central role in the development of cleft lip, especially in cases associated with recognized syndromes. Mutations in genes such as IRF6 (linked to Van der Woude syndrome), PVRL1 (ectodermal dysplasia), MSX1, and TBX22 have been identified as causative in syndromic clefting. However, for most cases—especially nonsyndromic cleft lip—the precise genetic cause remains elusive, though several candidate genes and genetic loci have been implicated 8 9 10.

Environmental Exposures

Environmental factors are also important contributors to cleft risk, particularly in genetically susceptible individuals. Key environmental risks include:

• Maternal smoking during pregnancy: Strongly associated with increased risk, particularly when certain genetic variants are present (e.g., GSTT1-null) 10.
• Alcohol consumption: Maternal alcohol use during pregnancy increases cleft risk 9.
• Nutritional deficiencies: Lack of essential nutrients such as folic acid during pregnancy may raise the risk 9.
• Certain medications or illnesses: Some prescription drugs and maternal health conditions may interfere with normal craniofacial development 9.

Gene-Environment Interactions

Emerging research highlights that it’s not simply genes or environment alone, but their interaction that shapes cleft risk. For instance, a child with a genetic susceptibility may only develop a cleft lip if exposed to specific environmental triggers during critical windows of embryonic development 7 8 10.

Syndromic vs. Nonsyndromic Clefts

About 70% of cleft lip cases are nonsyndromic, meaning they occur in isolation without other congenital anomalies. The remaining cases are syndromic, occurring as part of broader genetic syndromes, each with its own inheritance patterns and additional health implications 8 9.

Current Research and Future Directions

The ongoing mapping of genetic variants and improved understanding of environmental risks are paving the way for better prevention, risk assessment, and genetic counseling. Future breakthroughs may enable more targeted interventions to reduce cleft incidence 9 10.

Treatment of Cleft Lip

Treating cleft lip is a complex, multi-phase process that requires coordinated care from a team of specialists. The primary goals are to restore normal appearance and function, ensure healthy development, and support the individual’s psychosocial well-being.

Treatment Stage	Description / Purpose	Timing / Features	Source(s)
Surgical Repair	Closure of the lip (and palate if present)	Typically within 3–6 months	11, 13, 15
Presurgical Orthopedics	Mold the gums, lip, and nose for better outcomes	Before surgery	11
Palate Repair	Close the roof of the mouth, improve speech	9–18 months	12, 15, 16
Speech Therapy	Address articulation and resonance issues	Ongoing, as needed	11, 15
Dental & Orthodontic	Correct dental anomalies, align teeth/jaws	Childhood through adolescence	4, 5, 14
Revision Surgeries	Nose/lip revisions, bone grafts, fistula repair	School age to adolescence	12, 14, 16
Psychosocial Support	Emotional and social counseling, support groups	Throughout care	6, 11, 15

Table 4: Treatment Stages for Cleft Lip

Surgical Treatment

Primary lip repair is the foundational step, typically performed when the baby is 3–6 months old. The timing and technique depend on the child's health and the specific anatomy of the cleft. The main objectives are to restore a natural-looking lip, achieve functional muscle continuity, and facilitate feeding and speech. There is no universal consensus on the best surgical method; the choice often relies on the surgeon’s experience and the cleft’s severity 11 13 15.

• Palate repair is usually scheduled between 9 and 18 months of age if the palate is also involved. This helps in the development of normal speech and prevents food and fluids from leaking into the nose 12 15 16.
• Pre-surgical orthopedics: Some centers use devices to mold the gums, lip, and nose before surgery for better results 11.

Multidisciplinary and Long-Term Care

Managing cleft lip goes far beyond initial surgery. Ongoing, coordinated care is essential and may include:

• Speech therapy: Many children require help with speech articulation and resonance, especially if the palate is involved 11 15.
• Dental and orthodontic treatment: Addressing missing, malformed, or misaligned teeth is crucial for both appearance and function. Orthodontic interventions often begin in early childhood and may continue into adolescence 4 5 14.
• Secondary surgeries: These may include revision of the lip or nose, bone grafting to repair the gum ridge, or closure of oronasal fistulas (openings between the mouth and nose) 12 14 16.
• Orthognathic (jaw) surgery: In severe cases with significant jaw misalignment, corrective jaw surgery may be needed in the teenage years 14.

Psychosocial and Supportive Care

The emotional and psychological impact of living with a cleft lip should not be underestimated. Support from psychologists, social workers, and peer groups can greatly enhance coping and quality of life for both the child and their family 6 11 15.

Variations and Advances in Care

Treatment protocols vary worldwide, and research continues to refine the optimal sequence and techniques for the best possible outcomes. For example, the Oslo protocol for unilateral cleft lip and palate has shown some advantages over delayed hard palate closure, particularly in reducing certain complications. However, the evidence is still evolving, and individualized care remains key 16.

Lifelong Follow-up

Cleft care is not a “one-and-done” process. Multiple surgeries and ongoing therapies are often required well into adolescence and sometimes adulthood. Long-term studies show that, despite the need for several interventions (an average of nearly five surgeries per patient), most individuals achieve good functional and cosmetic outcomes 12.

Conclusion

Cleft lip is a complex condition with far-reaching effects on health, development, and quality of life. Early detection, multidisciplinary care, and ongoing support are essential for optimal outcomes. Here’s what we covered:

• Symptoms: Range from visible lip splits and nasal deformities to feeding, dental, speech, and psychosocial challenges.
• Types: Include unilateral, bilateral, complete, incomplete, and rare median clefts, with or without involvement of the palate.
• Causes: Stem from a multifactorial interplay of genetics, environment, and their interactions; both syndromic and nonsyndromic forms exist.
• Treatment: Requires staged surgical repair, coordinated therapies, dental and orthodontic work, and psychosocial support—often spanning many years.

Advances in genetics, surgical techniques, and comprehensive care continue to improve the lives of those born with cleft lip. With early intervention and multidisciplinary support, most children can look forward to healthy, fulfilling lives.