Congenital facial cleft except cleft lip and palate is relatively rare. The incidence rate is only 0.0 12%, accounting for 9.5% ~ 34% of all facial fissures (including cleft lip and palate). The incidence rate of male is higher than that of female, the incidence rate of left fissure is higher than that of right fissure, the incidence rate of Caucasians is higher than that of other races, and 75% of facial fissures are complicated with other complications.
Symptoms and signs
1. The midfacial fissure belongs to craniofacial fissure No.0 in Tisser classification. Among them, the most common facial soft tissue fissures are median cleft of upper lip and nasal deformity, and median cleft of lower lip.
The median cleft of the upper lip refers to the cleft of the midline of the upper lip or the secret cleft that only connects the skin and mucosal tissue. There are many clinical manifestations of the median cleft of the upper lip, which is only a cleft on the red edge of the lip, mostly caused by the ligament connected with the nasal columella. When the upper lip is completely cleft, labial frenum is located on both sides of the cleft, the gap between central incisors is too wide, there may be cracks between premolars, and the two anterior nasal ridges and incisors are inclined to the midline. The nose is forked, the columella is wide, sometimes the nostril atresia is asymmetric, and the alar cartilage and lateral cartilage are not developed laterally, which indicates that the forked nose is accompanied by a central groove. Some scholars have found that this is because there is a thick fibrous muscle band under the skin between the frontal bone and the alar bone, which pulls the nasal columella upward. The nasal bone is widened, flattened and thickened, the nasal septum is thickened, or it becomes two, or it is missing, and the maxillary development is acceptable.
Median cleft of the lower lip can be limited to soft tissue cleft, and mild cases only show all traces of the lower lip. In severe cases, not only the lower lip is cracked, but also the mandibular joint is cracked, and even the hyoid bone, thyroid cartilage and sternum are deformed, and the front part of the tongue is forked.
2. The facial oblique fissure belongs to the cheek deformities of craniofacial deformities No.3, No.4 and No.5 in Tisser classification, which are introduced respectively below.
The facial oblique fissure in craniofacial malformation No.3 is caused by the fracture or non-fusion of middle nasal process, lateral nasal process and maxillary process. Facial oblique fissure can be unilateral or bilateral, complete or incomplete. It is located near the inner canthus and alar, so the alar is defective, and the alar moves up to the affected inner canthus, and the nasolacrimal duct is abnormal, which is easy to be complicated with infection. The eye deformity is obvious, the inner canthus moves down and the lower eyelid is missing, which affects its protective effect on the eyeball. The medial canthus ligament is underdeveloped and dislocated. Fracture usually occurs between maxillary lateral incisors, canine teeth and pyriform foramen. There is no bone separation between nasal cavity and maxillary sinus, and there is no frontal process of maxilla.
Transverse facial fissure belongs to craniofacial malformation No.7 in Tisser classification, also known as the first mental arch syndrome, unilateral facial hypoplasia, lateral facial fissure and so on. , is a common type of facial deformity. The incidence was 1/3000 ~ 1/5000. There are mild facial asymmetry, abnormal external ear, abnormal mandibular morphology, and sometimes inconspicuous ear warts. Facial fissure can extend from the mouth to the external ear, but generally it does not exceed the front edge of the masseter muscle. During palpation, it can be found that there is a horizontal groove depression from the cheek skin down to the upper front of the external ear. It may be accompanied by malformations of middle ear and inner ear, and morphological abnormalities of mandible, maxilla, cheekbone and temporal bone. At the same time, parotid gland or duct can be missing, the fifth and seventh cranial nerves can also be involved, the soft palate and tongue are underdeveloped, and the mandibular branch, condyle and zygomatic arch are even missing. Due to the hypoplasia of maxilla, the vertical height of mandibular ramus is insufficient, and the occlusal surface is inclined to the head side.