Radical correction of secondary nasal deformity in unilateral cleft lip patients presenting late

It is universally acknowledged that correction of a cleft lip nasal deformity continues to be a difficult problem. In developing countries, it is common for patients with cleft lip deformities to present in their early or late teens for correction of severe secondary lip and nasal deformities retained after the initial repairs were carried out in infancy or early childhood. Such patients have never had the benefit of primary nasal correction, orthodontic management, or alveolar bone grafting at an appropriate age. Along with a severe nasal deformity, they present with alveolar arch malalignments and anterior fistulae. In the study presented here, a strategy involving a complete single-stage correction of the nasal and secondary lip deformity was used.In this study, 26 patients (nine male and 17 female) ranging in age from 13 to 24 years presented for the first time between June of 1996 and December of 1999 with unilateral cleft lip nasal deformity. Eight patients had an anterior fistula (diameter, 2 to 4 mm) and 12 patients had a secondary lip deformity. An external rhinoplasty approach was used for all patients. The corrective procedures carried out in a single stage in these patients included lip revision; columellar lengthening; repair of anterior fistula; augmentation along the pyriform margin, nasal floor, and alveolus by bone grafts; submucous resection of the nasal septum; repositioning of lower lateral cartilages; fixation of the alar cartilage complex to the septum and the upper lateral cartilages; augmentation of nasal dorsum by bone graft; and alar base wedge resections. Medial and lateral nasal osteotomies were performed only if absolutely indicated. The median follow-up period was 11 months, although it ranged from 5 to 25 months. Overall results have been extremely pleasing, satisfactory, and stable.In this age group (13 years of age or older), it is not fruitful to use a technique for nasal correction that corrects only one facet of the deformity, because no result of nasal correction can be satisfactory until septal deviations and maxillary deficiencies are addressed along with any alar repositioning. The results of complete remodeling of the nasal pyramid are also stable in these patients because the patients' growth was nearly complete, and all the deformities could be corrected at the same time, leaving no active deforming vector. These results would indicate that aesthetically good results are achievable even if no primary nasal correction or orthodontic management had been previously attempted.     

Primary correction of the unilateral cleft nasal deformity

An 18-year experience with the management of the unilateral cleft nasal deformity in 1200 patients is presented. A primary cleft nasal correction was performed at the time of lip repair in infancy; a secondary rhinoplasty was done in adolescence after nasal growth was complete. The technical details of the authors' primary cleft nasal correction are described. Exposure was obtained through the incisions of the rotation-advancement design. The cartilaginous framework was widely undermined from the skin envelope. The nasal lining was released from the piriform aperture, and a new maxillary platform was created on the cleft side by rotating a "muscular roll" underneath the cleft nasal ala. The alar web was then managed by using a mattress suture running from the web cartilage to the facial musculature. In 60 percent of cases, these maneuvers were sufficient to produce symmetrical dome projection and nostril symmetry. In the other 40 percent, characterized by more severe hypoplasia of the cleft lower lateral cartilage, an inverted U infracartilaginous incision and an alar dome supporting suture (Tajima) to the contralateral upper cartilage were used. Residual dorsal hooding of the lower lateral cartilage was most effectively managed with this suture. This primary approach to the cleft nasal deformity permits more balanced growth and development of the ala and domal complex. Some of the psychological trauma of the early school years may be avoided. Also, because of the early repositioning of the cleft nasal cartilages, the deformity addressed at the time of the adult rhinoplasty is less severe and more amenable to an optimal final result.     

Primary correction of unilateral cleft lip nasal deformity: a 10-year review

A 10-year follow-up of patients who underwent primary correction of their cleft lip nasal deformity is presented. These are the first 10 consecutive patients who were treated following a change in treatment plan in 1973. Primary correction of the cleft lip nasal deformity essentially consists in elevating the displaced alar cartilage at the time of lip repair. There has been no interference with nasal growth, and the position of the alar cartilages and nasal tip has been maintained.     

Resorbable internal splint: an adjunct to primary correction of unilateral cleft lip-nasal deformity

There is usually some relapse in position of the alar cartilage after primary repair of unilateral cleft lip. Therefore, preoperative or postoperative external splinting has been recommended to supplement either closed or open suspension of the alar cartilage. The authors present a method using a resorbable internal nostril splint to shield the positioned alar cartilage from deformational forces caused by scar, and thus avoiding the problems associated with external splinting. An internal nasal splint was placed in 15 infants during repair of unilateral complete cleft lip and nasal deformity. The nasal morphology was compared with that of 15 control patients who had the same nasolabial procedure without internal splinting. Average follow-up time was 20.4 months (range, 4 to 30 months). Photogrammetric analysis showed that asymmetry of the alar contours averaged 8.6 percent in the splinted patients, as compared with 23 percent for controls (p <0.01). Thus, alar asymmetry was decreased two-thirds in the splinted group. An internal resorbable nasal splint is an adjunct to open alar suspension in primary repair of the unilateral cleft lip nasal deformity. An internal nasal splint protects the corrected alar cartilage longer than an external splint and eliminates drawbacks, such as necrosis, cutaneous depression of the nostril sill, and patient noncompliance. This strategy of temporary internal support of healing cartilage has other applications.     

The use of nasal splints in the primary management of unilateral cleft nasal deformity

Primary surgical correction of the cleft lip nasal deformity is routinely performed at the Craniofacial Center at Chang Gung Memorial Hospital. Over time, however, there is a tendency for the lower lateral cartilage to retain its memory and, subsequently, recreate the preoperative nasal deformity. Therefore, it is current practice to use a nostril retainer for a period of at least 6 months to maintain the corrected position of the nose. The aim of this study was to qualitatively assess the benefit of postoperative nasal splinting in the primary management of unilateral cleft nasal deformity. Data from two groups of 30 patients with complete unilateral cleft lips each were retrospectively collected and analyzed. The first group served as a control (no nasal splints), and the second group used the nasal retainer compliantly for at least 6 months postoperatively. All patients had their primary lip repair at 3 months of age. A photographic evaluation of the results when the patients were between 5 and 8 years of age was conducted. The parameters used to assess the nasal outcome were nostril symmetry, alar cartilage slump, alar base level, and columella tilt. The first scores were based on residual nasal deformity, and the second set were based on overall appearance. It was found that the mean scores of residual nasal deformity for all four parameters in patients who used the nasal stent were statistically better than the scores of patients who did not (p values ranged from 0.0001 to 0.005). The overall appearance scores for the four parameters in the patients who used the nasal stent after surgery were also statistically better than the scores for those who did not (p values ranged from 0.0001 to 0.01). The results show that postoperative nasal splinting in the primary management of the unilateral cleft nasal deformity serves to preserve and maintain the corrected position of the nose after primary lip and nasal correction, resulting in a significantly improved aesthetic result. Therefore, it is recommended that all patients undergoing primary correction of complete unilateral cleft deformity use the nasal retainer postoperatively for a period of at least 6 months.     

Primary correction of the unilateral cleft lip nose: a 15-year experience

This paper reviews a 15-year personal experience based on 400 unilateral cleft nasal deformities that were reconstructed using a method that repositions the alar cartilage by freeing it from the skin and lining and shifts it to a new position. The rotation-advancement lip procedure facilitates the exposure and approach to the nasal reconstruction. The nasal soft tissues are transected from the skeletal base, reshaped, repositioned, and secured by using temporary stent sutures that readapt the alar cartilage, skin, and lining. The nasal floor is closed and the ala base is positioned to match the normal side. Good subsequent growth with maintenance of the reconstruction has been noted in this series. The repair does not directly expose or suture the alar cartilage. Improvement in the cleft nasal deformity is noted in 80 percent of the cases. Twenty percent require additional techniques to achieve the desired symmetry. This method has been used by the author as his primary unilateral cleft nasal repair and has been taught to residents and fellows under his direction with good results. This technique eliminates the severe cleft nasal deformity seen in many secondary cases.     

Primary definitive nasal correction in patients presenting for late unilateral cleft lip repair

Almost 25 percent of unilateral cleft lip and palate patients present with their deformity in their teens or later years in the developing world. Because more than 80 percent of the world population lives in the developing world, the established protocol for repair of these deformities is not applicable to these patients. Despite the magnitude, there are no significant reports in the literature that deal with this problem. Several issues need to be addressed, but the author limits himself here to the correction of the nasal deformity. The patients at this age are very much concerned with the aesthetic outcome. Procedures described hitherto for primary nasal correction in infants are not successful in restoring nasal shape and symmetry at this late age of presentation. Our experience with radical correction of secondary nasal deformity in unilateral cleft lip patients presenting late prompted us to extend the concept by undertaking a definitive primary correction of the nasal deformity in cleft patients presenting late. Twenty-two patients with unilateral cleft lip deformity (nine male patients and 13 female patients) with ages ranging from 13 to 22 years, presenting between August of 1997 and December of 2000, are included in this study. Of these, 11 patients had a cleft of the lip alone, eight also had a cleft of the alveolus, and three had a cleft of the palate continuous with the cleft lip. All patients showed some maxillary hypoplasia. An external rhinoplasty with lip repair was carried out in all patients. The corrective procedures on the nose included columellar lengthening; augmentation along the pyriform margin, nasal floor, and alveolus using bone grafts; submucous resection of the nasal septum; repositioning of lower lateral cartilages; and augmentation of nasal dorsum by bone graft. Clinical follow-up ranged from 4 to 24 months, and the median follow-up period was 13 months. Results have been very good, and much better than results seen earlier with other primary rhinoplasty techniques. While repairing unilateral cleft lip in adolescents, the author thinks it would be most appropriate to address the entire gamut of the deformity in a single stage, provide complete vector reorientation, and augment the hypoplastic elements by autologous tissue. It is not just the fear of poor follow-up, but that merely correcting the lip deformity in these patients without attempting definitive rhinoplasty, in the author's opinion, would be insufficient surgical intervention.     

Cleft lip nose correction with onlay calvarial bone graft and suture suspension in Oriental patients

To correct the secondary cleft lip nose deformity in Oriental patients, many alar cartilage mobilization and suspension techniques have been developed. However, these techniques have critical limitations. One of the limitations is the suspension vector, and another is suspension power. The suspension vector is from inferior to superior and from the deformed alar cartilage to the normal alar cartilage. Thus, the vector is not suitable for normal nasal tip projection. The suspension power is not satisfactory because Oriental people have underdeveloped, thin alar cartilages and thick skin. So, the suspended, deformed alar cartilage may relapse and pull the normal alar cartilage to the deformed side. To overcome these limitations, the authors use the cantilever calvarial bone graft for tip projection; it also serves as a strong, rigid framework for cartilage and soft-tissue suspension. Using these techniques, the authors can create normal nasal tip projection and a normal looking nasal aperture.     

Supratip deformity: a closer look

Supratip deformity, a hallmark of a poorly executed rhinoplasty or an inauspicious healing, continues to plague the novice often and the experts on occasion. A clinical and histopathologic study was conducted to search for the surgical causes of this deformity and its histologic presentation. An organized, logical management program was then developed. Clinically, supratip fullness was observed in both primary (26 of 298 patients; 9 percent) and secondary (40 of 112 patients; 36 percent) rhinoplasty candidates. In primary patients, the deformity was the result of inadequate tip projection (pseudodeformity), an overprojected caudal dorsum, a combination of both, or cephalically oriented lower lateral cartilages. In secondary patients, the deformity was caused by an underresected or overresected caudal dorsum, overresected midvault, underprojected tip (pseudodeformity), or a combination of some of these factors. The histopathologic evaluation demonstrated significant fibrosis in the supratip soft tissue of 14 of 16 patients undergoing secondary rhinoplasty without the injection of triamcinolone acetonide and in only 13 of 23 patients who underwent primary rhinoplasty (p<0.05). A supratip deformity can be eschewed by proper resection of the caudal dorsum, avoidance of dead space, restoration of adequate projection to the nasal tip, and an approximation of the supratip subcutaneous tissue to the underlying cartilage using a supratip suture, hence eliminating the dead space. If the problem is noted shortly after surgery, in the presence of collapsible consistency of the supratip tissue and adequate projection, the treatment is taping the supratip tissue as often as it is practical. If no favorable response is elicited in 6 to 8 weeks, thejudicious injection of a small amount of triamcinolone acetonide (0.2 to 0.4 cc of 20 mg/cc) in the deep subcutaneous tissue (not in the dermis) is done. The injection is repeated in 4-week intervals until the desired effect is achieved. If supratip fullness is the consequence of inadequate cartilage resection or inadequate tip projection, surgical correction is needed. The recalcitrant soft-tissue excess in the supratip area is resected, and the subcutaneous soft tissue is approximated to the underlying cartilage. If the dorsum was previously overresected, a cartilage graft to the caudal dorsum or midvault will create an optimal dorsal frame and reduce the potential for a recurrent supratip deformity.     

Repair of cleft lip with nonsurgical correction of nasal deformity in the early neonatal period

Auricular cartilage is soft and plastic at birth, so that congenital auricular deformities can easily be corrected nonsurgically in the early neonatal period. However, as the infant grows older, the flexibility of the auricle decreases. Alar cartilage exhibits the same elasticity as auricular cartilage in the early neonate. When a cleft lip is repaired, typically when the infant is about 3 months of age, it becomes difficult to correct the nasal deformity without surgical intervention. However, based on our experience, there is a fair possibility of correcting the cleft lip nasal deformity with a nonsurgical procedure in the early neonatal period. We performed cleft lip repair accompanied by nonsurgical correction of the nasal deformity in 44 neonates aged 2 to 7 days. A special retainer was placed in the affected nostril for 3 months. Following observation of 31 infants for 12 months or longer, their nasal shapes and symmetry were considered superior to those conventionally operated on at about 3 months of age. Except for one nasal infection, there were no complications.     

Secondary correction of the unilateral cleft lip nose using a conchal composite graft

The secondary deformity of the unilateral cleft lip nose has many components. One is the dorsal dislocation of the lateral crus of the alar cartilage. We used a conchal composite graft positioned between the piriform aperture and the lateral crus and the upper lateral cartilage to correct this dislocation in nine patients. We believe that this graft is effective because it elevates the lateral crus of the alar cartilage off the depressed piriform aperture. This technique is very simple to perform, and it is easy to achieve nasal symmetry. Our results have been quite satisfactory, with no recurrence of dorsal dislocation. The donor site was covered by a subcutaneous pedicled flap from the cephaloauricular sulcus, leaving an inconspicuous deformity.     

The Turkish delight: a pliable graft for rhinoplasty

In nose surgery, carved or crushed cartilage used as a graft has some disadvantages, chiefly that it may be perceptible through the nasal skin after tissue resolution is complete. To overcome these problems and to obtain a smoother surface, the authors initiated the use of Surgicel-wrapped diced cartilage. This innovative technique has been used by the authors on 2365 patients over the past 10 years: in 165 patients with traumatic nasal deformity, in 350 patients with postrhinoplasty deformity, and in 1850 patients during primary rhinoplasty. The highlights of the surgical procedure include harvested cartilage (septal, alar, conchal, and sometimes costal) cut in pieces of 0.5 to 1 mm using a no. 11 blade. The fine-textured cartilage mass is then wrapped in one layer of Surgicel and moistened with an antibiotic (rifamycin). The graft is then molded into a cylindrical form and inserted under the dorsal nasal skin. In the lateral wall and tip of the nose, some overcorrection is performed depending on the type of deformity. When the mucosal stitching is complete, this graft can be externally molded, like plasticine, under the dorsal skin. In cases of mild-to-moderate nasal depression, septal and conchal cartilages are used in the same manner to augment the nasal dorsum with consistently effective and durable results. In cases with more severe defects of the nose, costal cartilage is necessary to correct both the length of the nose and the projection of the columella. In patients with recurrent deviation of the nasal bridge, this technique provided a simple solution to the problem. After overexcision of the dorsal part of deviated septal cartilage and insertion of Surgicel-wrapped diced cartilage, a straight nose was obtained in all patients with no recurrence (follow-up of 1 to 10 years). The technique also proved to be highly effective in primary rhinoplasties to camouflage bone irregularities after hump removal in patients with thin nasal skin and/or in cases when excessive hump removal was performed. As a complication, in six patients early postoperative swelling was more than usual. In 16 patients, overcorrection was persistent owing to fibrosis, and in 11 patients resorption was excessive beyond the expected amount. A histologic evaluation was possible in 16 patients, 3, 6, and 12 months postoperatively, by removing thin slices of excess cartilage from the dorsum of the nose during touch-up surgery. This graft showed a mosaic-type alignment of graft cartilage with fibrous tissue connection among the fragments. In conclusion, this type of graft is very easy to apply, because a plasticine-like material is obtained that can be molded with the fingers, giving a smooth surface with desirable form and long-lasting results in all cases. The favorable results obtained by this technique have led the authors to use Surgicel-wrapped diced cartilage routinely in all types of rhinoplasty.     

Indications and use of composite grafts in 100 consecutive secondary and tertiary rhinoplasty patients: introduction of the axial orientation

The fragile alar rims are complex structures whose specialized and supportive skin ensures the competence of the external valves and the patency of the inlets to the nasal airways. A chart review was performed of 100 consecutive secondary or tertiary rhinoplasty patients in whom the author had placed composite grafts before February 1999. Follow-up continued for at least 12 months. In 94 percent of the patients, composite grafts were harvested from the cymba conchae by removing the cartilage with its adherent anterior skin. In 6 percent of the patients, independently indicated alar wedges supplied the grafts. Six patients required secondary procedures to thin the alar rims, but such revisions have not been necessary since primary contouring of the cartilaginous graft component was instituted. Three auricular donor-site complications (one keloid, two thickened graft contours) were successfully revised through office procedures. Prior cosmetic rhinoplasty in a patient with normal alar cartilage anatomy exceeded all other etiologies as the cause of the deformity for which composite grafts were indicated (50 percent). The second most common etiology was deformity from prior rhinoplasty in a patient with alar cartilage malposition (33 percent of patients). Congenital deformities (7 percent of patients), trauma (6 percent), and prior tumor ablation (4 percent) comprised the remaining etiologies. Composite grafts were used most frequently to correct alar notching or asymmetry in rim height (43 percent of patients) or to provide an increase in apparent or real nasal length (28 percent). External valvular incompetence (14 percent of patients), nostril or vestibular stenosis (11 percent), or combined vestibular stenosis and lateral alar wall collapse (4 percent) were less common indications. Most composite grafts were oriented in the coronal plane (parallel to the alar rims). However, nostril or vestibular stenosis was corrected by sagittally placed composite grafts, and a third orientation (axial plane), to the author's knowledge not described previously, was used in patients with combined nostril stenoses and flattening of the alar walls. In this secondary rhinoplasty series, iatrogenic alar rim deformities or stenoses following cosmetic rhinoplasty dominated other causes requiring composite graft reconstruction (83 percent of patients). Of these 83 patients, 39.7 percent had preexisting alar cartilage malpositions, further supporting the importance of making accurate anatomical diagnosis part of every preoperative rhinoplasty plan.     

The alar contour graft: correction and prevention of alar rim deformities in rhinoplasty

One of the most common problems affecting both the primary and secondary rhinoplasty patient is deformity of the alar rim. Typically, this deformity is caused by congenital malpositioning, hypoplasia, or surgical weakening of the lateral crura, with the potential for both functional and aesthetic ramifications. Successful correction and prevention of alar rim deformities requires precise preoperative diagnosis and planning. Multiple techniques of varying complexity have been described to treat this common and challenging problem.Over the past 6 years (1994 through 2000), the authors have employed a simple technique in 123 patients for alar retraction that involves the nonanatomic insertion of an autogenous cartilage buttress into an alar-vestibular pocket. Among the 53 patients who underwent primary rhinoplasty in this study, 91 percent experienced correction or prevention of alar notching or collapse. However, correction was achieved for only 73 percent of the patients who underwent secondary rhinoplasty; many of whom had alar retraction secondary to scarring or lining loss. In patients with moderate or significant lining loss or scarring, a lateral crural strut graft is recommended. The alar contour graft provides the foundation in the patient undergoing primary or secondary rhinoplasty for the reestablishment of a normally functioning external nasal valve and an aesthetically pleasing alar contour. This article discusses the anatomic and aesthetic considerations of alar rim deformities and the indications and the surgical technique for the alar contour graft.     

Primary correction of unilateral cleft lip nasal deformity in Asian patients: anthropometric evaluation

Previously it was thought that primary correction of nasal deformity in cleft lip patients would cause developmental impairment of the nose. It is now widely accepted that simultaneous correction of the cleft lip nasal deformity has no adverse effect on nasal growth. Thus, the authors tried to evaluate the results of primary correction of cleft lip in Asian patients. Of 412 cases of cleft lip, 195 cases were corrected by means of the conventional method from June of 1992 to June of 1997, and 217 cases were corrected by simultaneous rhinoplasty from July of 1997 to October of 2001. The average patient age was 3 months. Photographs and anthropometric evaluation were used to evaluate the results. Nasal tip projection, columellar length, and nasal width were measured in 60 randomized normal children, 30 randomized children treated with the conventional method, and 30 randomized children with primary nasal repair. Data were analyzed using t tests, and the level of significance was 5 percent (p < 0.05). In cases of simultaneous repair, nasal tip projection and columellar length were increased 24.8 percent and 28.8 percent, respectively. Nasal width was increased 12.3 percent in the cases of simultaneous repair and 12.6 percent in the cases without primary rhinoplasty. Simultaneous repair of cleft lip and nasal deformity in Asian patients showed that more symmetry of nostril and nasal dome projection and better correction of buckling and alar flaring were achieved. More balanced growth and development of the alar complex was achieved, and no interference with nasal growth was encountered.     

A comparative study of the skin envelope of the unilateral cleft lip nose subsequent to rotation-advancement and triangular flap lip repairs

The secondary nasal skin envelope asymmetries were studied after unilateral cleft lip repair using the original (obsolete) rotation-advancement (Millard I) and the triangular flap techniques (Bardach's modification). Secondary correction of the nasal deformity was not performed in either group. Our findings indicated that in both groups, vertical asymmetries of the nasal skin envelope were similar. The alar dome on the cleft side was depressed, the columella was shorter on the cleft side, and there was hooding at the nostril apex. The principal difference between the two lip repairs was observed in the horizontal dimension of the nasal skin envelope. The position of the alar base was more normal following the Millard I repair, while the triangular flap repair left the alar base laterally displaced. When considered together with flattening of the cleft alar dome, a horizontal skin-envelope deficiency from middome to lateral alar crease was produced in the Millard I group. More lateral positioning of the alar base after the triangular flap technique minimized this horizontal skin deficiency. The triangular flap technique produced a secondary nasal deformity that looked worse but was easier to correct. The clinical implications of these findings are discussed.     

Onlay cartilage graft of the alar lateral crus for cleft lip nasal deformities

The onlay cartilage grafting technique is described for treatment of unilateral or bilateral cleft lip nasal deformities. The alar cartilage is exposed through rim and intercartilagenous incisions. The cephalic half of the alar cartilage is excised, similar to the technique of traditional tip rhinoplasty. The harvested cartilage is applied to the intact caudal cartilage in layered fashion and secured with absorbable sutures. If necessary, successive layers may be added. These grafts provide a sturdy, yet delicate framework for a more normal appearing alar rim. We have performed this procedure on 16 patients, ages 10 to 41. Follow-up intervals range from 13 to 40 months, with a mean of 19 months. Results have been rated good-to-excellent by patients and surgeons. There has been no recurrence of the deformity. The only complication has been one nasal vestibule synechia.     

Oronasal fistula repair with three layers

We present an innovative method for closure of oronasal fistulas involving a three-layer repair, consisting of septal mucosa flap, bone or cartilage graft, and palatal mucosa flap. The septal mucosa flap closes the nasal side of the defect. This is an inferiorly based flap along the nasal floor and consists of septal mucosa from the side opposite the oronasal fistula. A slit is created in the remaining layers of the nasal septum, allowing the flap to be delivered into the defect. When the septal flap is folded down in this fashion, it exposes nasal septal bone and cartilage. The bone and cartilage are harvested and are used to create the middle layer of the three-layer fistula repair. The oral layer of the repair is provided by a palatal mucosa transposition flap. This method allows the bone/cartilage graft to be sandwiched between two vascular layers. We have successfully used the three-layer repair on three patients. All of the oronasal defects were 2 cm in size. All patients are at least 1 year after repair with 100 percent closure; thus, no oronasal leakage. The flaps both septal and palatal resulted in no morbidity once healed. Specifically, the surgically created slit in the nasal septum is well mucosalized and barely discernible. Also, no nasal obstruction occurs from the septal flap on the floor of the nose. We perform the procedure on an outpatient basis. The three-layer repair can be used in adult patients with oronasal fistulas of the middle and posterior hard palate up to 3 cm in size. This technique is not recommended for children.     

A comparison of the immunohistochemical localization of type I and type II collagens in craniofacial cartilages of the rat.

The immunohistochemical localization of types I and II collagen was examined in the following 4 cartilaginous tissues of the rat craniofacial region: the nasal septal cartilage and the spheno-occipital synchondrosis (primary cartilages), and the mandibular condylar cartilage and the cartilage at the intermaxillary suture (secondary cartilages). In both primary cartilages, type II collagen was present in the extracellular matrix (ECM) of the whole cartilaginous area, but type I collagen was completely absent from the ECM. In the secondary cartilages, type I collagen was present throughout the cartilaginous cell layers, and type II collagen was restricted to the ECM of the mature and hypertrophic cell layers. These observations indicate differences in the ECM components between primary and secondary craniofacial cartilages, and that these differences may contribute to their modes of chondrogenesis.