Changes in soft tissue thickness after Le Fort I osteotomy in different cleft types

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1 Arja Heliövaara, DDS, PhD Orthodontist Jyri Hukki, MD, PhD Senior Consultant in Plastic Surgery Reijo Ranta, DDS, PhD Docent and Senior Orthodontist Aarne Rintala, MD, PhD Assistant Professor of Plastic Surgery Emeritus Head Cleft Center Department of Plastic Surgery Helsinki University Central Hospital Helsinki, Finland Reprint requests: Dr Arja Heliövaara Cleft Center Department of Plastic Surgery Helsinki University Central Hospital P. O. Box 266 FIN HUS Finland Fax: Int J Adult Orthod Orthognath Surg Vol. 16, No. 3, 2001 Changes in soft tissue thickness after Le Fort I osteotomy in different cleft types The soft tissue thickness before and after Le Fort I osteotomy was evaluated in 46 cleft patients. The sample consisted of 10 patients with isolated cleft palate (CP, mean age 25.5 years); 10 patients with bilateral cleft lip and palate (BCLP, mean age 21.7 years); and 26 patients with unilateral cleft lip and palate (UCLP, mean age 22.9 years). Patients with bimaxillary surgery, simultaneous rhinoplasty, or V-Y plasty of the upper lip were excluded. Soft tissue changes were analyzed by cephalograms taken shortly before surgery and at 6 months postoperatively. Horizontal advancement varied from 4.1 mm in the UCLP group to 5 mm in the BCLP group. The vertical lengthening varied from 3.7 mm in the CP group to 7.2 mm in the BCLP group. In all cleft types, thinning of the subnasal area, superior labial sulcus, and upper lip (anterior nasal spine subnasale, point A soft tissue point A, and prosthion labrale superius) took place. Significant thinning of the upper lip occurred in the UCLP and BCLP patients. Surgical changes of the lower lip and mandibular area were small and insignificant. There were significant differences in soft tissue thicknesses between different types of clefts. The subnasal area and superior labial sulcus were significantly thicker in the CP group than in the BCLP or UCLP groups, both pre- and postoperatively. The upper lip was thickest in the BCLP group preoperatively but thickest in the CP group postoperatively. The upper lip was thinnest in the UCLP group both before and after the operation. (Int J Adult Orthod Orthognath Surg 2001;16: ) Improved facial harmony and a balanced profile are major goals of orthognathic surgery for both the cleft patient and the surgical/orthodontic team. However, treatment planning and prediction of facial esthetic changes are difficult, especially in cleft patients. Predictions based on cephalometric standards alone are not appropriate. Most of the previous studies of soft tissue changes after Le Fort I osteotomy deal with patients with unilateral cleft lip and palate (UCLP). 1 6 However, differences in skeletal and soft tissue profiles exist between different cleft types. When compared to patients with isolated cleft palate (CP), the adolescent with unilateral or bilateral cleft lip and palate (BCLP) undergoing 207 orthognathic surgery is usually characterized by more severe maxillary growth deficiency and more severe retrusion of the facial profile. In addition, in patients with CLP, multiple residual clefting problems may exist. These include bony defects, soft tissue scarring from previous surgeries, absence of lateral incisors, alveolar bone defects, asymmetry, muscle pull, various dental malocclusions, different internal and external nasal form and function, and differences in upper lip morphology. 7 The purpose of this study was to compare changes in the soft tissue thickness after Le Fort I osteotomy in patients with isolated CP, BCLP, and UCLP without bimaxillary surgery, simultanous rhinoplasty, or V-Y plasty of the upper lip.

2 208 Heliövaara et al Table 1 Comparability of the cleft groups, mean horizontal and vertical surgical change, and relapse (calculated from point A) according to type of cleft Mean Horizontal Vertical age at Age surgical surgical Type of surgery range change Range change Range Mean relapse after 6 months cleft n Male Female (y) (y) (mm) (mm) (mm) (mm) Horizontal (%) Vertical (%) CP BCLP UCLP Patients and methods Patients, surgical technique, and orthodontics The series consisted of 46 Caucasian cleft patients who had undergone a Le Fort I osteotomy at the Cleft Center, Department of Plastic Surgery, Helsinki University Central Hospital, between 1987 and The initial consecutive series consisted of 92 cleft patients, but 46 patients were excluded because of bimaxillary surgery (n = 5), simultaneous rhinoplasty (n = 8), simultaneous V-Y plasty (n = 15), syndromes or combined clefts (n = 8), or missing or poor quality radiographs (n = 10). The comparability of the cleft groups, the immediate postoperative skeletal surgical change, and relapse after 6 months (calculated from point A) are given in Table 1. The method of primary lip closure at the age of 3 to 6 months varied from modifications of Veau, Le Mesurier, and Skoog to Millard I and II. The method of palatal closure at the age of 1.5 to 2 years was either Veau-Wardill-Kilner or modified Cronin pushback. Secondary operations before Le Fort I osteotomy were done to 35 of the 46 patients. In the CP group, 1 patient had undergone a secondary operation, velopharyngeoplasty. All 10 BCLP patients had undergone secondary operations. Bone grafting of the alveolar cleft had been performed on 7 BCLP patients at the age of 12 to 19 years. Rhinoplasty and lip correction had been done to all patients. In addition, 7 BCLP patients had had closure of fistulae (frequently in connection with bone grafting), and 3 received velopharyngeoplasty. Twenty-four patients of the UCLP group (n = 26) had undergone secondary operations. Bone grafting of the alveolar cleft had been done to 19 patients at the age of 10 to 17 years. Other secondary procedures included rhinoplasty (n = 20), closure of fistulae (n = 18, frequently in connection with bone grafting), lip correction (n = 15), and velopharyngeoplasty (n = 6). Le Fort I osteotomies were begun in our Cleft Center in The operations included in this study were performed by 4 surgeons and 1 senior orthodontist. The osteotomies were grafted using bone from the iliac crest and fixed with titanium plates. Prefabricated interocclusal splints were used during the operation to determine the occlusion. The splint was removed immediately after surgery. No postoperative maxillomandibular fixation was applied. Patients were given orthodontic treatment before and/or after the osteotomy. During postoperative orthodontics, maxillomandibular elastics were used individually for minor corrections of intercuspation. Cephalometric measurements Standardized lateral cephalometric radiographs, taken with the head positioned according to the Frankfort horizontal plane, with molar teeth occluded and lips in repose, were used. The radiographs were taken shortly before surgery, immediately after surgery, and at 6 months postoperatively (CP group mean 5.5 months, range 3 to 8 months; BCLP group mean 5.8 months,

3 Landmarks used A = point A A = soft tissue point A ANS = anterior nasal spine B = point B B = soft tissue point B Cm = columella Gn = soft tissue gnathion Go = gonion Id = infradentale Li = labrale inferius Ls = labrale superius Me = menton MP = mandibular plane (tangent to lower border of mandible through Me) N = nasion N = soft tissue nasion Pog = pogonion Pog = soft tissue pogonion Pr = prosthion Pn = pronasale S = sella Sn = subnasale SN = sella-nasion line Sts = stomion superius x-axis = horizontal line through N rotated 7 degrees upward from the SN line y-axis = vertical line perpendicular to the horizontal line through S Fig 1 Cephalometric landmarks and lines used in the study (see Landmarks used list for definitions). range 4.3 to 8 months; and UCLP group mean 6.1 months, range 4.8 to 7.9 months). When soft tissue changes were analyzed, the preoperative and 6-month postoperative radiographs were used to avoid the period of postoperative edema and to ensure that soft tissue stability was established. The cephalograms were traced twice by a computerized digitizer. The computer was programmed to calculate the mean of the 2 digitalizations, which were to be accurate to within 1 mm. The subsequent cephalometric tracings were superimposed on the structures of the anterior cranial base. The change in maxillary position was established by superimposing a template of the preoperative outline of the maxilla on subsequent radiographs using anatomic best fit. To differentiate horizontal and vertical changes, an x-y coordinate system was used. The x-axis was determined as a line through N rotated 7 degrees upward from the SN line. The y-axis was determined as a vertical line perpendicular to the horizontal line, through S. The reference points and landmarks are shown in Fig 1. All measurements were corrected for cephalometric enlargement. Int J Adult Orthod Orthognath Surg Vol. 16, No. 3, x-axis y-axis The Student t test was used in the statistical analysis. Results S Go 7 degrees Me Cephalometric surgical changes and significance according to type of cleft are given in Table 2. Six months postoperatively, there was a significant change in maxillary position (S-N-A) and facial convexity (N -Pn-Pog ) in all but the BCLP group. Anterior facial height (N-ANS) and upper lip length (Sn-Sts) increased significantly in all cleft groups. In addition, a significant improvement in the nasolabial angle (Cm-Sn-Ls) was noticed in the UCLP group. Thinning of the subnasal area, superior labial sulcus, and upper lip (ANS-Sn, A-A, and Pr-Ls) was noticed in all cleft groups from before surgery to 6 months after surgery (Tables 2 and 3). Significant thinning of the subnasal area (by 2.1 mm) and upper lip (by 1.6 mm) was noticed in the UCLP group, and significant thinning of the upper lip (by 3.4 mm) was seen in the BCLP group. The subnasal area and the upper labial sulcus were significantly thicker in N N' ANS A Sn A' Id B Pr Pog B' Gn' Ls Sts Li Pog' Pn Cm MP

4 210 Heliövaara et al Table 2 Cephalometric surgical changes and significance CP (n = 10) BCLP (n = 10) UCLP (n = 26) T1 T2 T1/T2 T1 T2 T1/T2 T1 T2 T1/T2 Mean SD Mean SD P value Mean SD Mean SD P value Mean SD Mean SD P value S-N-A (deg) * * S-N-B (deg) S-N-Pog (deg) SN/MP (deg) N-ANS (mm) * * * ANS-Me (mm) S-Go (mm) S-N -A (deg) * S-N -B (deg) S-N-Pog (deg) S-N -Pog (deg) * N -Pn-Pog (deg) * * Cm-Sn-Ls (deg) * N -Sn (mm) Sn-Gn (mm) Sn-Sts (mm) * * * ANS-Sn (mm) * A-A (mm) Pr-Ls (mm) * * Id-Li (mm) B-B (mm) Pog-Pog (mm) T1 = Immediately preoperative; T2 = 6 months postoperative. *Statistically significant (P <.05). Table 3 Difference in mean (in mm) and P values of pre- and postoperative soft tissue profile thicknesses by type of cleft Preoperative Postoperative CP-BCLP CP-UCLP UCLP-BCLP CP-BCLP CP-UCLP UCLP-BCLP Difference Difference Difference Difference Difference Difference (mm) P value (mm) P value (mm) P value (mm) P value (mm) P value (mm) P value ANS-Sn 4.9 0* 2.6 0* * 5.8 0* * * A-A * 2.9 0* * * Pr-Ls * * * Id-Li * * B-B Pog-Pog * * *Statistically significant (P <.05).

5 the CP group than in the UCLP or BCLP groups, both preoperatively (by 2.6 to 4.9 mm) and postoperatively (by 2.6 to 5.8 mm). The upper lip was thickest in the BCLP group preoperatively, but because of the significant thinning that occurred in the BCLP group, the upper lip was thickest in the CP group postoperatively. The upper lip was thinnest in the UCLP group both pre- and postoperatively. The surgical changes in the thickness of the lower lip (Id-Li), mentolabial sulcus (B- B ), and soft tissue chin (Pog-Pog ) were small and insignificant. However, there were significant differences between the cleft types. The lower lip and the soft tissue chin were significantly thicker in the BCLP group than in the CP group, both pre- and postoperatively (Tables 2 and 3). Discussion The present study showed significant soft tissue improvement in facial profiles after Le Fort I osteotomy in cleft patients. There was great individual variation, as shown also in previous studies. 1 6 In clinical practice, cephalometrics is indispensable and widely used in diagnosis and treatment planning. When soft tissue profiles are evaluated, the limitations of radiographic cephalometry, such as reliability of landmark identification or discrepancy in lip posture, have to be considered. The soft tissue thickness in the superior labial sulcus and lip areas can be affected by lip posture. Although the radiographs were taken with the lips in repose, discrepancies may appear between measurements taken with relaxed lips, closed lips, and lips with several degrees of contraction in the circumoral muscles. 8 In addition, the difficulty in comparing serial cephalometric radiographs should be considered. Caution is needed when discussing the clinical importance of surgical changes less than 1 mm. When soft and hard tissue changes are within 1 or 2 mm, the method error becomes more critical, 9 especially when the sample size is small. Repositioning of the maxilla changes the appearance and function of the nose and lip. Typically there is widening of the base of the nose and associate flattening Int J Adult Orthod Orthognath Surg Vol. 16, No. 3, of the upper lip. 10 Thinning of the subnasal area, superior labial sulcus, and upper lip was noticed in all cleft groups as a result of surgery. Significant thinning of the upper lip was noticed in UCLP and BCLP groups. Both horizontal advancement and vertical lengthening were greatest in the BCLP group. The greater surgical advancement can be associated with more muscle pull and greater tension on the soft tissue and residual scar tissue. Tendency to relapse may also affect the tension of the soft tissue. The skeletal relapses in the BCLP and UCLP groups were larger than in the CP group, both horizontally and vertically. The vertical relapse was larger than the horizontal relapse in all cleft groups. Downward movement of the maxilla stretches both the muscular sling and associated soft tissues. 11 It has been shown that V-Y plasty can be used to control the unfavorable changes in the upper lip. 12 A V-Y plasty minimizes vertical shortening and maintains greater anteroposterior thickness of the upper lip as compared to not using the technique. A V- Y plasty also improves upper lip esthetics. 12 It has been previously shown that in patients with UCLP, the V-Y plasty significantly increased both the anteroposterior thickness of the upper lip and the vertical lip profile. 6 In that study, the 1-year postoperative horizontal change in the upper lip profile (A ) was 80% of the skeletal change (A). Vertically, the soft tissue change was less (40%), but it increased to 58% if V-Y plasty was used. 6 Patients who received simultanous V-Y plasty were excluded from the present study. Significant differences were noticed in soft tissue thickness between different types of clefts both pre- and postoperatively. The subnasal area and superior labial sulcus were significantly thicker in the CP group than in the UCLP or BCLP groups, both preand postoperatively. On the other hand, the upper lip was thickest in the BCLP group preoperatively, but because of the significant thinning after surgery in the BCLP group, the upper lip was thickest in the CP group postoperatively. The upper lip was thinnest in the UCLP group both pre- and postoperatively. According to Smahel, 13 the flattening of the skeletal profile in complete

6 212 Heliövaara et al and incomplete isolated CP was masked by an increased thickness of the upper lip (at the level of Pr).Thus, in isolated CP, soft tissue compensation may help to lessen the effect of the underlying skeletal discrepancy preoperatively, in contrast to the cleft lip and palate, where, because of the reduced thickness (of the upper lip), the soft tissue profile is even flatter than the skeletal profile of the face. 14 It has been reported that adult patients with BCLP exhibit a shorter upper lip and increased vertical length of the lower lip-chin complex than patients with UCLP. 15 When compared to patients with isolated CP, patients with UCLP or BCLP can display residual esthetic, anatomic, and functional deformities of the upper lip. The repaired cleft lip of the UCLP patients is thinner and less flexible. 3 Lip scars, asymmetries, vertical excess or deficiency, horizontal deficiency (tight lip), muscle malalignment, and functional and cosmetic defects in the vermilion and/or lip area are commonly seen in repaired unilateral clefts. 16 Bilateral cases include the above but also have unique residual defects, including philtrum abnormalities, vermilion deficiency, and buccal sulcus deficiency. 16 In addition to the differences in initial dysmorphology, surgery, growth, and function between different cleft types, secondary procedures entail the possibilty of additional scar tissue and further deviation in growth and function. Most of the patients in the UCLP group and all patients in the BCLP group had had 1 or more secondary operations, whereas only 1 patient in the CP group had had a secondary operation. The residual clefting problems, such as deviant nasal structures, alveolar bone defects, and missing upper lateral incisors, in patients with cleft lip and palate may further affect the muscle pull, morphology, and function of the upper lip. Surgical technique and skill, individual tissue reaction to surgery, and healing capacity are important factors in this respect but difficult parameters to measure. The surgical changes in the thickness of the lower lip, mentolabial sulcus and soft tissue chin were small and insignificant. This is in agreement with Ewing and Ross, 3 who noticed that horizontal changes in mandibular soft tissue thickness were minimal after orthognathic surgery in UCLP patients. In the present study, however, there were significant differences between the cleft groups. The lower lip was thicker in the UCLP group and significantly thicker in the BCLP group than in the CP group, both pre- and postoperatively. In UCLP patients, the lower lip is often everted and hypertrophied in appearance, which may be a result of reduced intercommissural width secondary to upper lip surgery or of chronic mentalis muscle hypertrophy, which develops to compensate for the loss of upper lip flexibility. 17 It seems that in persons with UCLP, the lower lip is habitually elevated, possibly compensating for the deficient maxilla and upper lip. 3 Establishment of a more normal jaw relationship after advancement of the maxilla would permit an improved lower lip configuration, even without mandibular surgery. 3 Lip thickness and fullness and a balanced lip profile are essential components of facial attractiveness. Gross facial imbalance is discernible, but it is difficult to quantitate imbalance for clinical use. According to Holdaway, 18 in an individual with balanced facial musculature, the upper lip thickness between the upper portion of the maxillary alveolar process and the outer lip surface approximates lip thickness in the region of the crown of the incisor. Although the dimensions used in this study were not identical, the patients with BCLP showed greatest lip imbalance both pre- and postoperatively, whereas the patients with isolated CP showed the greatest balance. In patients with UCLP, asymmetries may complicate the situation. Three-dimensional analyses of UCLP patients have shown that there is a greater degree of soft tissue movement on the cleft side than the noncleft side. 19 These results underscore the difference in soft tissue thickness in patients with isolated CP, BCLP, and UCLP. Moreover, the importance of secondary soft tissue corrections either simultanously or after the maxillary osteotomy is stressed. In most patients with CP, a Le Fort osteotomy alone may correct the maxillary deficiency both skeletally and esthetically, whereas in most patients with UCLP and BCLP, reconstruction of the skeletal deficiency and occlusion

7 by orthognathic surgery provides a favorable foundation on which final soft tissue revisions can be carried out. References 1. Freihofer HP Jr. The lip profile after correction of retro-maxillism in cleft and non-cleft patients. J Maxillofac Surg 1976;4: Araujo A, Schendel SA, Wolford LM, Epker BN. Total maxillary advancement with and without bone grafting. J Oral Surg 1978;36: Ewing M, Ross RB. Soft tissue response to orthognathic surgery in persons with unilateral cleft lip and palate. Cleft Palate Craniofac Surg 1993;30: Hui E, Hägg EU, Tideman H. Soft tissue changes following maxillary osteotomies in cleft lip and palate and non-cleft patients. J Craniomaxillofac Surg 1994;22: Al-Waheidi EMH, Harradine NWT, Orth M. Soft tissue profile changes in patients with cleft lip and palate following maxillary osteotomies. Cleft Palate Craniofac J 1998;3: Heliövaara A, Hukki J, Ranta R, Rintala A. Soft tissue profile changes after Le Fort I osteotomy in UCLP patients. J Craniomaxillofac Surg 2000;28: Posnick JC, Thompson B. Modification of the maxillary Le Fort I osteotomy in cleft-orthognathic surgery: The bilateral cleft lip and palate deformity. J Oral Maxillofac Surg 1993;51: Burstone CJ. Lip posture and its significance in treatment planning. Am J Orthod 1967;53: Mansour S, Burstone C, Legan H. An evaluation of soft tissue changes resulting from Le Fort I maxillary surgery. Am J Orthod 1983;84: Int J Adult Orthod Orthognath Surg Vol. 16, No. 3, Schendel SA, Carlotti AE. Nasal considerations in orthognathic surgery. Am J Orthod Dentofac Orthop 1991;100: Proffit WR, Turvey TA, Phillips C. Orthognathic surgery: A hierarchy of stability. Int J Adult Orthod Orthognath Surg 1996;11: Wolford LM. Effects of orthognathic surgery on nasal form and function in cleft patient. Cleft Palate Craniofac J 1992:29; Smahel Z. Variations in craniofacial morphology with severity of isolated cleft palate. Cleft Palate J 1984;21: Smahel Z, Brejcha M. Differences in craniofacial morphology between complete and incomplete unilateral cleft lip and palate in adults. Cleft Palate J 1983;20: Chaisrisookumporn N, Stella JP, Epker BN. Cephalometric profile evaluations in patients with cleft lip and palate. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1995;80: Turvey TA, Vig WL, Fonseca RJ. Maxillary advancement and contouring in the presence of cleft lip and palate. In: Turvey TA, Vig WL, Fonseca RJ (eds). Facial Clefts and Craniosynostosis. Principles and Management. Philadelphia: Saunders, 1996: Ross RB, Johnston MC. Cleft Lip and Palate. Baltimore: Williams and Wilkins, Holdaway RA. Soft tissue cephalometric analysis and its use in orthodontic treatment planning. Part II. Am J Orthod 1984;85: McCance AM, Orth M, Moss JP, et al. Three-dimensional analysis techniques Part 4: Three-dimensional analysis of bone and soft tissue to bone ratio of movements in 24 cleft patients following Le Fort I osteotomy: A preliminary report. Cleft Palate Craniofac J 1997;43:58 62.