•David S. Precious, DDS, M.Sc., FRCD(C)•

Surgery should reconstruct both the form and the function of the divided face such that balanced growth of the facial skeleton can take place. A sound knowledge of the initial faults and their post-operative sequelae enables the clinician to adapt techniques according to the needs of each case. The primary surgical procedure, performed when a child is 3 to 5 months old, is designed to systematically correct the abnormal anatomy. To correct the nasal deformity, the surgeon must obtain an ascension of the lower lateral cartilage with projection of the dome and an axial rotation of the lateral crus. In primary surgery, mucosal incisions must be short to prevent nostril constriction secondary to scar contraction, and for this reason the blind subcutaneous dissection must be both delicate and accurate. Muscle suturing is done in two planes: deep and superficial. Once these fundamental relationships have been surgically created, their maintenance can be assured with the use of a silastic intranasal retainer, stabilized by stay sutures for the first week after surgery. After that week, the retainer can be removed, cleaned and replaced in the nose on a regular schedule for 10 to 12 months. The nasal retainer has proven to be very useful in maintaining anatomical corrections achieved through functional cheilorhinoplasty (Figs. 2a and 2b). In our experience, both nasal airway patency and nostril symmetry are improved through the use of the nasal retainer (Figs. 3a and 3b).

Fig. 2a: Primary lip-nose surgery, before operation.	Fig. 2b: Primary lip-nose surgery, after operation. Note nasal retainer in place.
Fig. 3a: Distorted anatomy before operation.	Fig. 3b: Normal anatomy restored and retained by accurate lip-nose muscle surgery.

Primary Cleft Palate

There are three distinct regions of the mucoperiosteum covering the palate: (1) the palatine region — the thin, smooth lining covering the middle and posterior parts of the vault, corresponding roughly to the dimensions of the overlying nasal floor; (2) the maxillary region — the thick lining that covers the palate between the palatine and gingival regions, has rugae and is rich in blood vessels, nerves and connective tissue; and (3) the gingival region — the region that is intimately related to the maxillary dentoalveolus. It is the thick, maxillary mucoperiosteum, so important in the transverse and vertical growth of the palate, with which the surgeon must take special care in surgery of the hard palate.

In total bilateral cleft palate, the palatine part is missing but, usually, the gingival and maxillary regions are essentially normal. This explains why, in unoperated bilateral cleft palate, the development of the palatal vault is almost normal, the exceptions being the vomer and the palatine shelves themselves.

In classical palatorrhaphy techniques, large, widely undermined flaps of the maxillary region are swung medially to cover the defect of the palatine part. The resulting bilateral donor areas of exposed bone eventually undergo wound contraction and scarring. From its new position, the displaced maxillary mucoperiosteum cannot play its important role in transverse and vertical growth of the palatal vault. Furthermore, because this tissue is thick (unlike the thin palatine mucoperiosteum that is normally situated here), there is a "filling in" effect, which further compromises the depth of the palatal vault. The nasal fossae, normally under the influence of the palatine region of mucoperiosteum, do not fully develop their transverse dimension, which in turn can affect nasal airway patency.

It is also common in classic palatorrhaphy to obtain the nasal layer of the two-layer closure through the use of flaps of vomerine mucosa. This technique establishes an insufficient vertical dimension of the maxilla and therefore also of the nasal fossae, the net result of which favours a vertically deficient, retrodisplaced maxilla and overclosure of the mandible.²

In total unilateral cleft palate, the same problems exist with classic palatorrhaphy as in the bilateral case, except that because the vomer is bent to the non-cleft side, the transverse and vertical growth distortions are compounded by dysymmetry.

Staging of the surgical procedures based on variations of the individual case should be planned such that it is possible to respect the principles of anatomy and physiology of the three regions of mucoperiosteum that cover the palate. In complete cleft lip and palate, the soft palate is closed at the same time as the cleft lip at about 3 to 5 months of age ^{(Fig. 4)}. The surgical goal is to establish both the continuity and the function of the muscles of the soft palate.

Fig. 4: Soft palate muscular repair at the same time as primary lip surgery at 5 months of age.

Adequate length of the soft palate can be achieved without either complex multiple Z-plasties or micro-surgical techniques. Incisions are made on the margins of the cleft of the soft palate, slightly favouring the nasal side. To obtain the best exposure of the levator muscle, which is retracted toward the nasal side, a small triangle of mucosa is excised from the nasal surface of the divided velum on both sides. Reconstitution of the levator veli palati as well as the palatopharyngeus and palatoglossus muscles is prerequisite to obtaining adequate soft palate length. Adequate soft tissue mobilization can easily be realized by meticulous muscle dissection. The tensor palati and superficial portion of the palatopharyngeus muscles are freed from the posterior border of the palate so that their orientation from longitudinal to transverse can be accomplished. Muscle reconstruction, including the palatoglossus, establishes a functional sphincter of the soft palate. No vomer flap is employed.

Primary, early (within the first 18 months of life), autogenous bone grafting in reconstruction of clefts of the palate and alveolus has been demonstrated in most treatment centres to fall short of desired therapeutic results. Even when the technique used avoids disruption of vomerine mucosa, the quantity of bone present at the times of eruption of the maxillary permanent incisor and canine teeth is simply insufficient. It is generally agreed that these bone grafts do not preclude the need for early secondary alveolar bone grafts.

After conventional primary closure of a cleft lip there is inevitable scar tissue, oral nasal fistula, inadequate support for the ala of the nose and absence of bone in the region of the future permanent lateral incisor and canine teeth. The goals of secondary alveolar bone grafting (performed at about 5 to 6 years of age) are:

• closure of vestibular and palatal oral nasal fistulae

• provision of bone of sufficient quantity and appropriate quality to allow eruption of the permanent lateral incisor (if present) and canine teeth

• provision of support for the lateral ala of the nose and the skeletal nasal base

• provision of suitable bony architecture of the premaxilla and the anterior face of the maxilla on the cleft side to support accurate nasolabial muscle reconstruction

• establishment of a functional nasal airway on the cleft side.

The success of secondary alveolar bone grafts is, to some extent, time dependent. If the bone graft is performed before eruption of the permanent canine tooth, the result is almost always successful.

References

1. Precious DS, Delaire J. Surgical considerations in patients with cleft deformities. In: Bell WH, editor. Modern practice in orthognathic and reconstructive surgery. Philadelphia, PA: Saunders; 1992. Vol. 1, Ch. 14.

2. Delaire J, Precious DS. Avoidance of the use of vomerine mucosa in primary surgical management of velopalatine clefts. Oral Surg Oral Med Oral Pathol 1985; 60:589-97.

3. Delaire J, Precious DD. Influence of the nasal septum on maxillonasal growth in patients with congenital labiomaxillary cleft. Cleft Palate J 1986; 23:270-7.

4. Precious DS, Delaire J. Clinical observations of cleft lip and palate. Oral Surg Oral Med Oral Pathol 1993; 75:141-51.

5. Precious DS. Craniofacial growth and development. In: Peterson L, editor. Principles of oral and maxillofacial surgery. Toronto: Lippincot; 1992.