Causes of Deviated Asymmetrical Palate in Adults
A deviated asymmetrical palate in adults is most commonly caused by congenital factors, developmental asymmetries during growth, or acquired conditions, with craniofacial malformations being the most severe underlying cause. 1, 2
Classification of Palatal Asymmetry Causes
Congenital Causes
- Craniofacial malformations such as palatopharyngo schisis (cleft palate) 1
- Hemifacial microsomia 1, 3
- Unilateral clefts of the lip and palate 3
- Syndromes with facial asymmetry (Treacher Collins, Goldenhar, Klippel-Feil, PHACE, Parry-Romberg) 4
- Unilateral palate hypoplasia (extremely rare) 5
Developmental Causes
- Rotation displacement of upper jaw/piriform aperture 1, 2
- Left-right differences in facial width that develop during growth 1, 2
- Asymmetrical growth patterns during development 6
- Tilted occlusion plane signifying an off-horizontal upper jaw 1
- Natural developmental asymmetry (all skulls show some degree of right-left asymmetry in the hard palate) 6
Acquired Causes
- Trauma to facial structures 3
- Post-surgical complications 2
- Neuromuscular disorders affecting palatal function 5
- Tumor resection affecting palatal structure 5
- Viral infections (rare, typically causing palatal palsy rather than structural deviation) 7
Anatomical Considerations
The asymmetry can manifest in several ways:
- Isolated lateral placement of piriform aperture 1
- Non-horizontal alar base 1
- More pronounced facial asymmetry with cheek flattening and slanting of the midface 1
- Lower jaw asymmetry compounding the palatal deviation 1
- Posterior part of palate tends to be more asymmetric (4.6%) than the anterior part (2.8%) 6
Evaluation Framework
When evaluating palatal asymmetry, it's important to:
- Use the point of central facial reference (between the medial canthi) as the only constant reference 2
- Assess if the vertical midline properly intersects the glabella, nasal dorsum, nasal tip, columellar base, philtrum, upper incisors, and chin 2
- Evaluate the occlusal plane, which may be tilted in cases of upper jaw asymmetry 1
- Consider that head position can complicate determination of facial balance in about 10% of patients 2
Clinical Implications
Understanding the cause of palatal asymmetry is crucial because:
- Congenital cases may require early intervention if function is compromised 2
- Developmental asymmetries may benefit from orthodontic treatment or orthopedic correction during growth 3
- Acquired asymmetries need targeted treatment addressing the underlying cause 2
- Severe cases may require surgical correction 4
Palatal asymmetry is rarely an isolated finding and often exists as part of a broader pattern of facial asymmetry, which should be evaluated comprehensively to determine the most appropriate treatment approach.