A long-term, controlled-outcome analysis of in utero versus neonatal cleft lip repair using an ovine model.

Successful open repair of a cleft lip in utero has the advantage of scarless wound healing in the fetus. Unfortunately, no long-term outcome studies have been performed to evaluate the efficacy of these repairs. Moreover, no study to date has compared the long-term results of an in utero cleft lip repair to a similar, control-matched, newborn cleft repair. This study was performed to evaluate the 9-month outcome of in utero cleft lip surgery compared with an identical cleft lip repair performed on infant lambs. In utero epithelialized cleft lips were created through an open hysterotomy in sixteen 65-day-old fetal lambs (term = 140 days) using methods described by Longaker et al. Eight of 16 animals underwent subsequent in utero repair of these clefts at 90 days gestational age. The repair of the remaining eight animals was delayed until 1 week postpartum. At 9 months, the animals were analyzed for changes in lip contour and for the degree of scarring by hematoxylin and eosin and Masson's trichrome collagen staining. Two animals in each group died from preterm labor. Of the animals that survived to term, all repaired lips had some degree of abnormality postoperatively. One of six lips repaired in utero dehisced before delivery. Three of six neonatal repairs dehisced in the first postoperative month. In the remaining animals with intact lip repairs, the vertical lip height on the repaired side was an average of 9 to 12 mm shorter than the normal lip in both the in utero and neonatally repaired animals. Phenotypically, the postnatally repaired animals had more lip distortion and visible notching. Histologically, the in utero repair was scarless and the neonatal repairs had scar throughout the entire vertical height of the lip with an associated loss of hair in this region. Maxillary growth was also evaluated. There was no inhibition of maxillary growth in the animals that underwent in utero cleft lip repair. However, in the neonatal repair group, significant maxillary retrusion was evident. Compared with the cleft side of the maxilla, horizontal growth was decreased by 11 percent (p = 0.01). Compared with the intrauterine repair group, there was a 17-percent decrease in horizontal maxillary width (p = 0.01). Straight-line in utero repair of a cleft lip produces a better long-term result in terms of maxillary growth than a similar repair performed postnatally in the ovine model. There was no diminution in maxillary growth in the animals treated in utero. Histologically, in utero repair of clefts was indeed scarless. However, both lip repairs produced lips that were significantly shorter than their contralateral noncleft sides. This degree of lip shortening would require a secondary lip revision, thereby defeating the purpose of performing an intrauterine repair. Comparisons now need to be made between in utero and neonatal repairs using a Millard-type rotation advancement technique before intrauterine treatment can be considered to be more beneficial than our current treatment modalities.     

Bilateral cleft lip and nasal repair

SUMMARY: The bilateral cleft lip and nasal repair has remained a challenging endeavor. Techniques have evolved to address concerns over unsatisfactory features and stigmata of the surgery. The authors present an approach to this complex clinical problem that modifies traditional repairs described by Millard and Manchester. The senior author (H.S.B.) has developed this technique with over 25 years of surgical experience dealing with the bilateral cleft lip. This staged lip and nasal repair provides excellent nasal projection, lip function, and aesthetic outcomes. Lip repair is performed at 3 months of age. Columellar lengthening is performed at approximately 18 months of age. A key component of this repair focuses on reconstruction of the central tubercle. A triangular prolabial dry vermilion flap is augmented by lateral lip vermilion flaps that include the profundus muscle of the orbicularis oris. This minimizes lateral lip segment sacrifice and provides improved central vermilion fullness, which is often deficient in traditional repairs. The authors present the surgical technique and examples of their clinical results.     

Experience with the functional cleft lip repair

The first 12 functional cleft lip repairs performed on unselected consecutive patients immediately following the completion of training by the author are presented. Previous reports on this cleft lip repair have shown excellent results but have always been based on patients operated on by the originator of the procedure. This report gives credence to the ease with which a cleft lip repair that gives reproducible good results can be taught and learned even by plastic surgeons with limited experience. It reviews the technical steps of the procedure, which emphasizes wide undermining and release of the orbicularis oris muscle on the lateral side of the cleft to allow redraping and lengthening of the lip skin, step-by-step layered closure of the mucosa, muscle, and skin, and further vertical lengthening of the lip with a Z-plasty skin closure. Three elements that are difficult to achieve or restore with cleft lip revision are evaluated: (1) achievement of a good skin scar, (2) maintenance of the alar-facial groove, and (3) achievement of adequate lip height without sacrificing horizontal lip length. Ten of the 12 patients had a satisfactory scar, 9 patients had a good alar-facial groove, and all patients had a normal-appearing horizontal lip length. Nine patients required secondary surgery; however, in six patients, this included correction of the nasal deformity that was not corrected at the time of cleft lip repair.     

Outpatient cleft lip repair

The emphasis on cost reduction and increased efficiency in health care delivery has prompted an increase in outpatient (ambulatory) surgical procedures. A retrospective review of the perioperative management of patients undergoing cleft lip repair at two urban tertiary pediatric hospitals was performed to assess the safety of outpatient cleft lip repair. The hospital database at Childrens Hospital Los Angeles was searched to find all patients who had been operated on for cleft lip repair during calendar years 1999 and 2000. Two groups were identified from Childrens Hospital Los Angeles: the outpatient cleft lip repair group (patients discharged the same day as the operation; n = 91) and the inpatient cleft lip repair group (n = 14). A data set was acquired from the Royal Children's Hospital in Melbourne, Australia, using the same criteria, for fiscal years 1998 to 2000 (n = 50). All patients from Royal Children's Hospital had operations as inpatients. Parameters considered for each group were age, sex, race, ethnicity, length of hospital stay, preexisting medical conditions or diagnoses, complications, and readmissions or presentation to the emergency department within 4 weeks of operation. The Childrens Hospital Los Angeles outpatient group had three readmissions that were considered to be complications of the operation. The Childrens Hospital Los Angeles inpatient group had one readmission attributable to a complication. The Royal Children's Hospital group also had one readmission for a complication. There was no significant difference in the complication rate of the Childrens Hospital Los Angeles outpatient group and the Royal Children's Hospital group (p > 0.05). There was also no significant difference in the complication rate of both of the Childrens Hospital Los Angeles groups compared with the Royal Children's Hospital group (p > 0.05). This study indicates that cleft lip repair performed in an outpatient setting may be a safe alternative to the inpatient operation. Certain preexisting medical conditions, however, may dictate the need for inpatient hospitalization after repair.     

Reconstruction of the superior labial sulcus in secondary bilateral cleft lip deformities: an inverted U-shaped flap.

A shallow buccal sulcus deformity following bilateral cleft lip repair is not rare. A variety of techniques are described for the secondary reconstruction of a deficient sulcus. Most of these are associated with a variable amount of contraction with subsequent obliteration of the sulcus. In this article, an inverted U-shaped flap is described for the secondary reconstruction of the deficient sublabial sulcus. In these patients, mobility of the upper lip was severely restricted, so orthodontic treatment was not possible. This technique was used in nine patients whose primary cleft lip repairs were performed in different institutions. The amount of re-adhesion or contraction was negligible, because a bare surface was not left behind and skin or mucosal grafts were not used. By advancing the lateral segments of the lip medially, projection of the upper lip was increased. The procedure resulted in adequate upper lip mobility for all patients, and sufficient sulcus was maintained during 1 to 6 years of follow-up. The patients experienced no difficulty with orthodontic appliances after this reconstruction.     

Early repair and breast-feeding for infants with cleft lip

This study attempts to define the effect of early repair and breast-feeding on the outcome of cleft lip surgery. The first part deals with 100 consecutive cleft lip repairs categorized retrospectively by age at operation. Forty-nine patients were operated on during the first 3 weeks of life; 51 at an older age. There were no statistically significant differences in complication rate between the groups (14 and 18 percent, respectively). A subgroup of 26 infants was operated on at a week or less of age; these sustained significantly fewer complications (8 percent). There was no apparent difference in the operative results as defined by whether or not the child needed a subsequent revision. A second group of 60 mothers was offered the choice of breast-feeding their babies immediately following operation. Sixteen breast-fed for a minimum of 6 weeks, 22 were fed by means of a cup or syringe, and 22 started breast-feeding but converted to a bottle within 6 weeks. No complications attributable to breastfeeding were observed, and the rate of weight gain was definitely enhanced in the breast-feeding group. Hospital stay was shortened by an average of over a day (33 percent) as compared with those fed by cup. This effect was related to the easier transition from IV administration to oral intake when breast-fed. We are currently encouraging early repair and breast-feeding in the full-term baby as the optimum method of management of newborns with cleft lip.     

The Tennison Lip repair revisited

Tennison presented his method for the repair of the single cleft. He was the first to recognize and to preserve the cupid's bow by lowering the peak in the margin of the cleft. He incised the medial side of the cleft and filled the space with a triangular flap from the lateral side. We have modified the Tennison repair based on the vertical height of the normal side, as did Randall and Hagerty. We make the lip 1 mm shorter in the vertical height than the normal side because some of our repairs were too long. Other modifications include a 1-mm offset at the vermilion, and in certain lips that are too long in the newborn, a triangle is excised beneath the alar base to shorten the vertical height. The details for planning the incisions and accomplishing the surgery are given. Certain patients required a V-to-Y procedure to augment a vermilion deficiency, but none of these patients required a secondary procedure. This emphasizes the need for careful planning to get it right at the primary repair. The operation is indicated for the incomplete cleft to the very wide cleft, and in no patient was a lip adhesion required. We no longer operate on the nose at the primary repair.     

A model for fetal cleft lip repair in lambs.

Fetal wounds heal without inflammation and scar formation. This phenomenon may, in the future, be applicable to human cleft lip and palate repair. However, extensive experimental work must first be done to document the benefits of in utero repair. We developed a large animal model for creation and repair of a complete cleft lip and alveolus using fetal lambs. The cleft lip and alveolus deformity was created in eight 75-day-gestation fetuses (term = 145 days) and either repaired in three layers or left unrepaired. There were four sham-operated fetuses, and all animals were alive at harvest. Repaired, unrepaired, and control fetuses were harvested at 7, 14, 21, and 70 days following surgery. The unrepaired fetuses demonstrated a complete cleft lip and alveolus with an oronasal fistula. The maxilla was asymmetrical, with the greater segment deviated toward the cleft and with decreased anterior maxillary width. In contrast, repaired cleft lip and alveolus animals showed no scar, normal thickness of the lip, and a symmetrical maxilla. Histologic analysis of the repaired wounds showed evidence of tissue regeneration without scar formation. The results of this preliminary study indicate that the fetal lamb cleft lip and alveolus model is technically feasible with an excellent survival rate. Healing occurs without scar formation. In the repaired animals, the maxilla was symmetrical. This model will be used to document facial growth following in utero repair of a cleft lip and alveolus.     

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.     

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.     

The influence of lip repair with and without soft-tissue undermining on facial growth in beagles

The present study was designed to test the hypothesis that undermining of the soft tissues on the surface of the maxilla at the time of lip repair in unilateral cleft lip, alveolus, and palate results in more severe craniofacial growth aberrations than lip repair alone. Sixty-seven purebred beagles were used in this experiment. The animals were divided into four groups: two control groups (unoperated and unrepaired) and two experimental groups (lip repair without undermining and lip repair with undermining). Lip pressures were monitored in all groups. Significantly higher lip pressures were observed in animals with soft-tissue undermining. Cephalometric measurements were analyzed using univariate and multivariate techniques. The results of this study indicate that lip repair performed with soft-tissue undermining results in more severe craniofacial growth aberrations than lip repair performed alone.     

Functional cleft lip repair: a sequential, layered closure with orbicularis muscle realignment

A lip repair based on anatomic and electric stimulation studies of the orbicularis muscle in unilateral cleft lip has previously been reported by one of the authors. Following some early modifications, this technique has been used on 125 primary lip repairs. The details of the present technique are described here. The advantages of the procedure, in addition to its functional reconstruction of the orbicularis muscle, are in its applicability to clefts of all widths and superior scar formation. The sequential nature of the procedure and freedom from commitment to a fixed, measured pattern at the outset makes the teaching of the method easier and the achievement of a pleasing result more predictable.     

Lip pressure changes following lip repair in infants with unilateral clefts of the lip and palate

The present study was designed to quantitatively assess lip pressure changes following cleft lip repair in infants with unilateral cleft lip, alveolus, and palate. Lip pressure measurements were taken using an electronic transducer system developed especially for this study. Lip pressure was monitored from 3 months (preoperatively) through 2 years of age in cleft and normal control children. Findings from the present study confirm the hypothesis that lip repair in infants with unilateral cleft lip and palate significantly increases lip pressure and that increased lip pressure remains significantly higher than in normal control children for the 2-year duration of the study. Thus increased lip pressure when the palate is unrepaired has to be considered as a factor modulating subsequent craniofacial growth.     

A prospective evaluation of the prevalence of submucous cleft palate in patients with isolated cleft lip versus controls.

Although there is an established relationship between cleft lip and overt cleft palate, the relationship between isolated cleft lip and submucous cleft palate has not been investigated. To test the hypothesis that patients with isolated cleft lip have a greater association with submucous cleft palate, a double-armed prospective trial was designed. A study group of 25 consecutive children presenting with an isolated cleft lip, with or without extension through the alveolus but not involving the secondary palate, was compared with a control group of 25 children with no known facial clefts. Eligible patients were examined for the presence of physical criteria associated with classic submucous cleft palate, namely, (1) bifid uvula, (2) absence of the posterior nasal spine, and (3) zona pellucida. Nasoendoscopy was subsequently performed just after induction of general anesthesia, and the findings were correlated with digital palpation of the palatal muscles. Patients who did not satisfy all three physical criteria and in whom nasoendoscopy was distinctly abnormal relative to the control group were classified as having occult submucous cleft palate. Classic submucous cleft palate was found in three study group patients (12 percent), all of whom had flattening or a midline depression of the posterior palate and musculus uvulae on nasoendoscopy and palpable diastasis of the palatal muscles under general anesthesia. An additional six study group patients (24 percent) had similar nasoendoscopic criteria and palpable diastasis of the palatal muscles; they were classified as having occult submucous cleft palate. No submucous cleft palate was identified in the control group. Seventeen patients in the study group had an alveolar cleft with a 53 percent (9 of 17) prevalence of submucous cleft palate. In the present study, classic submucous cleft palate in association with isolated cleft lip was 150 to 600 times the reported prevalence in the general population. All children with an isolated cleft lip should undergo peroral examination and speech/resonance assessment no later than the age of 3 years. Any child with an isolated cleft lip with velopharyngeal inadequacy or before an adenoidectomy should be assessed by flexible nasal endoscopy to avoid missing an occult submucous cleft palate.     

Upper lip measurements at the time of surgery and follow-up after modified rotation-advancement flap repair in unilateral cleft lip patients

The purpose of this prospective study was to determine whether unilateral cleft lip repaired by the rotation-advancement flap will grow short on the repaired side. This study involved 56 patients with nonsyndromic unilateral cleft lip (31 with complete and 25 with incomplete cleft lip) who underwent a rotation-advancement flap repair by a single surgeon between 1989 and 1997. Eleven patients were lost to follow-up. Forty-five patients have been followed for a varying period of between 8 and 84 months (mean = 37 months). The upper lip was measured immediately after the lip repair and follow-up using calipers. The growth ratios of vertical, horizontal, and nostril sill dimensions were compared between the cleft side and the noncleft side of the same face. Statistical analysis was performed to compare the growths between the cleft and noncleft sides. There was not a significant difference in the growth ratios of vertical (Wilcoxon signed rank test, p = 0.85) and horizontal dimensions (Student's t test, p = 0.18) between the cleft and noncleft sides. There was, however, a statistically significant difference in the growth ratios of nostril sill width between the cleft and noncleft sides (Student's t test, p = 0.02). Our findings indicated that a repaired unilateral cleft retained the vertical and horizontal dimensions determined at the time of the initial repair.     

A comparative analysis of healing of surgical cleft lip corrected in utero and neonates.

We studied the healing process in surgically created cleft lips in fetal mice and compared it with that in newborn mice with cleft lips. Our purpose was to determine the time for optimal healing, defined as minimal scarring, for a repaired cleft lip. Full-thickness paramedian lip incisions were made in NMRI mice in utero, in 2- and 4-day-old neonates, and in adults (n = 10 in each experimental and control group). The healing process was studied by biochemical analysis of hyaluronic acid and hydroxyproline content in the repaired cleft tissue. We found that the production of hyaluronic acid remained stable during the healing period and was similar in all experimental groups. However, there was an unexplained but consistent depression in the hyaluronic acid content of fetal tissue 2 days after repair. Hydroxyproline was present in the fetal healing tissue, but in a low concentration, starting 4 days after surgical incision of the lip. The production of hydroxyproline in 2-day-old neonates was similar to that in the fetuses throughout the healing period (p less than 0.0005). However, the production of hydroxyproline increased in 4-day-old neonatal and adult tissues. In conclusion, we found an optimal healing period for mice with minimal collagen production in the late fetal stage, and this lasted 2 days after birth.     

New technique for correction of the microform cleft lip using vertical interdigitation of the orbicularis oris muscle through the intraoral incision

A microform cleft lip has three major components: (1) a minor defect of the upper vermilion border with loss of the mucocutaneous ridge; (2) a narrow ridge of tissue, resembling an exaggerated philtral column extending to the nostril sill; and (3) a deformity of the nostril. To attain the muscle continuity without an external scar on the upper lip, the author introduced a new method for the correction of a microform cleft lip deformity using vertical interdigitation of the orbicularis oris muscle through the intraoral incision to create the philtrum. Through the intraoral incision, a full-thickness incision is made down to the mucosa and the posterior portion of the muscle. Then, the remaining portion of the muscle is dissected. The medial and lateral muscle flaps are also detached from the oral mucosa and completely exposed and split into two leaves. The upper leaf of the lateral muscle flap is sutured to the dermis on the philtral dimple and base of the upper leaf of the medial muscle flap. Two leaves of each muscle flap are sutured together to create a vertical interdigitation to increase the thickness of the philtral column and to provide continuity of the muscle. A total of 12 patients with microform cleft lip were treated between August of 2001 and October of 2002. Seven of the patients were male and five were female, with an age range of 1 to 43 years. The follow-up period ranged from 6 months to 15 months, with an average follow-up of 9 months. The results of vertical interdigitation of the muscle were examined. All patients were satisfied with their results. The orbicularis oris muscle provided continuity and preserved good function. In all cases, the operation scar was not visible on the depressed philtral groove on the cleft side. Correction of cleft lip nasal deformity was performed in four patients and alar base advancement was performed in two patients. The advantages of the proposed procedure include the creation of an anatomically natural philtrum without an external visible scar through the intraoral incision, preservation of the continuity and function of the muscle, and sufficient augmentation of the philtral column by the vertical interdigitation of the muscle.     

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.     

Histologic, histochemical, and ultrastructural analysis of soft tissues from cleft and normal lips.

The cause of cleft lip remains speculative. The nature and extent of pathophysiologic changes in cleft lip muscle are controversial. This study was undertaken to better understand the developmental processes at work. There were two groups of patients. In group 1, 40 fresh tissue specimens were taken from 22 patients who were 2 to 5 months old-their age at the time of their primary cleft lip repair. In group 2, eight control specimens were collected from six children who were seen in the emergency department with lip lacerations. Fresh specimens fixed in neutral buffered formalin were evaluated by the use of hematoxylin and eosin with Luxol fast blue, Bielschowsky, and Masson trichrome stains. Fresh frozen tissue was histochemically assessed by the use of hematoxylin and eosin, modified Gomori trichrome, and adenosine triphosphatase. Ultrastructural analysis was performed on fine sections of glutaraldehyde-fixed tissue. Histologic examination revealed increased endomysial and perimysial collagen in cleft specimens with evidence of muscle-bundle size variation and nonneurogenic atrophy. Insignificant differences were observed between cleft-side and noncleft-side specimens when the means of 200 counts of neural-tissue bundles in the subdermis were compared (p = 0.093). Histochemical examination revealed no typical checkerboard pattern, but a preponderance of type 2 fiber was seen. By means of electron microscopy, increased numbers of subsarcolemmal mitochondria were found in cleft, noncleft, and control specimens. Increased absolute numbers of mitochondria and variations in size, shape, and crystal arrangement were identified. In conclusion, there is no evidence of deficient neural supply in the cleft lip. There is also no evidence of neurogenic muscle atrophy or a metabolic abnormality. There are characteristic myopathic changes. These, in concert with the observed interstitial fibrosis, may have far-reaching implications for growth and function.     

Accelerated Wound Closure In Vitro by Fibroblasts from a Subgroup of Cleft Lip/Palate Patients: Role of Transforming Growth Factor-α

In a fraction of patients surgically treated for cleft lip/palate, excessive scarring disturbs maxillary growth and dento-alveolar development. Since certain genes are involved in craniofacial morphogenesis as well as tissue repair, a primary defect causing cleft lip/palate could lead to altered wound healing. We performed in vitro wound healing assays with primary lip fibroblasts from 16 cleft lip/palate patients. Nine foreskin fibroblast strains were included for comparison. Cells were grown to confluency and scratch wounds were applied; wound closure was monitored morphometrically over time. Wound closure rate showed highly significant differences between fibroblast strains. Statistically, fibroblast strains from the 25 individuals could be divided into three migratory groups, namely “fast”, “intermediate”, and “slow”. Most cleft lip/palate fibroblasts were distributed between the “fast” (5 strains) and the “intermediate” group (10 strains). These phenotypes were stable over different cell passages from the same individual. Expression of genes involved in cleft lip/palate and wound repair was determined by quantitative PCR. Transforming growth factor-α mRNA was significantly up-regulated in the “fast” group. 5 ng/ml transforming growth factor-α added to the culture medium increased the wound closure rate of cleft lip/palate strains from the “intermediate” migratory group to the level of the “fast”, but had no effect on the latter group. Conversely, antibody to transforming growth factor-α or a specific inhibitor of its receptor most effectively reduced the wound closure rate of “fast” cleft lip/palate strains. Thus, fibroblasts from a distinct subgroup of cleft lip/palate patients exhibit an increased migration rate into wounds in vitro, which is linked to higher transforming growth factor-α expression and attenuated by interfering with its signaling.