Evaluation of treatment outcome in cleft maxillary hypoplasia treated by rigid external distractor: a cephalometric study.

ORIGINAL ARTICLE

Evaluation of Treatment Outcome in Cleft Maxillary Hypoplasia Treated by Rigid External Distractor: A Cephalometric Study Nandakishore Sahoo, MDS, Ajay Premanand Desai, MDS, Balakrishnan Jayan, MDS, and Vishal Gupta, MDS Objective: The aim of the study was to cephalometrically evaluate hard and soft tissue changes in cases of cleft-induced maxillary hypoplasia treated by distraction osteogenesis using rigid external distractor (RED). Methods: Fifteen cases of cleft-induced maxillary hypoplasia were selected applying the inclusion and exclusion criteria. The cases were operated on under general anesthesia for distraction osteogenesis using RED. Cephalometric evaluation was done at the end of presurgical orthodontics (C1), 1 week after removal of RED (C2), and at the end 12 months postoperatively (C3). The hard tissue parameters considered were Sella Nasion point A angle, Point A-Nasion-point B angle, distance from condylion to point A, anterior nasal spine-menton to Nasion-menton ratio, and upper incisor distance to N vertical. The soft tissue parameters included facial contour angle, nasolabial angle, upper lip to E-line, and lower lip to E-line. Result: There were 8 males and 7 females with an average age of 13.07 years. The range of maxillary advancement was 8 to 24.5 mm with an average of 14.46 mm. The cephalometric data were compared using paired t test and 1-way analysis-of-variance test. All the hard tissue changes except SNB were statistically highly significant (P 9 0.0001). The percentage of relapse was 13.72% at SNA, 13.3% at ANB, 9.83% for maxillary depth, 8.99% for distance of the upper incisor to N perpendicular and 20.73% for facial contour angle, 2.16% for nasolabial angle, 25.69% for distance of UL to E-line, and 25.12% for distance of LL to E-line. Soft tissue relapse except nasolabial angle after 1 year was more as compared with hard tissue. Conclusions: All the cephalometric parameters except SNB angle showed significant improvement. However, the significant percentage of relapse should be considered in the preoperative planning. What Is This Box? A QR Code is a matrix barcode readable by QR scanners, mobile phones with cameras, and smartphones. The QR Code links to the online version of the article.

From the Department of Dental Surgery, Armed Forces Medical College, Pune, Maharashtra, India. Received February 3, 2013. Accepted for publication August 23, 2013. Address correspondence and reprint requests to Ajay Premanand Desai, MDS, Department of Dental Surgery, Armed Forces Medical College, Wanowrie, Pune, Maharashtra India, PIN 411040; E-mail: [email protected] The authors report no conflicts of interest. Copyright * 2014 by Mutaz B. Habal, MD ISSN: 1049-2275 DOI: 10.1097/SCS.0000000000000374

The Journal of Craniofacial Surgery

Key Words: Midfacial deficiency, RED, cephalometric analysis, relapse (J Craniofac Surg 2014;25: 143Y148)

Y

oung children and adolescents with operated cleft lip and palate (CLP) present with midface deficiency, which can be attributed to primary anomaly, surgical interventions leading to dysplastic, and deficient growth of maxilla.1,2 Growth deficiency is predominantly in transverse and sagittal plane leading to a concave facial profile, crossbite, reverses overjet. Functional problems include speech concerns due to velopharyngeal insufficiency (VPI), respiratory problems, and masticatory difficulties. They often present with psychological problems and social acceptance deficit due to facial aesthetics and speech. Traditionally, orthognathic surgery is prescribed to improve maxillomandibular relations and facial aesthetics. The orthognathic surgeries commonly used for cleft maxillary hypoplasia are surgical advancement of maxilla with Le Fort I osteotomy, mandibular setback by bilateral sagittal split ramus osteotomy, or a combination. The results were not quite stable as 25% to 40% relapse has been reported.3 Ever since the classic work on midface advancement on animal models by distraction osteogenesis (DO) by Rachmiel et al4 and the successful human application by Polley and Figueroa5 by rigid external distractor (RED), a lot of issues on stability and relapse have been overcome. Large advancement has been made possible with minimal deterioration of VPI. In view of the above, a prospective interventional cephalometric study was undertaken with the following aim.

AIM The aim of the study was to cephalometrically evaluate the hard and soft tissue changes in cases of cleft-induced maxillary hypoplasia treated by DO by RED.

MATERIALS AND METHODS Pretreatment and posttreatment cephalograms of 15 cases of cleft maxillary hypoplasia who required only midface advancement treated between January 2007 to December 2010 by DO with RED and fulfilling the following inclusion and exclusive criteria were included in the study (Table 1).

Inclusion Criteria a. Male and female cases of cleft maxillary hypoplasia older than 11 years b. Both operated unilateral CLP (UCLP) and bilateral CLP cases that had undergone secondary alveolar bone grafting c. Reverse overjet of minimum 4 mm d. Patients and parents willing to participate in the study

& Volume 25, Number 1, January 2014

Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.

143


Sahoo et al


TABLE 1. Patient Database Patient No.

Sex

Diagnosis

Age, y

Distraction, mm

F M M M M F F M F M F M M F F

CLP with maxillary hypoplasia CLP with maxillary hypoplasia CLP with maxillary hypoplasia Bilateral CLP with maxillary hypoplasia Goldenhar syndrome with CLP and maxillary hypoplasia CLP with maxillary hypoplasia CLP with maxillary hypoplasia CLP with maxillary hypoplasia Goldenhar syndrome with CLP and maxillary hypoplasia CLP with maxillary hypoplasia Bilateral CLP with maxillary hypoplasia CLP with maxillary hypoplasia Maxillary hypoplasia Bilateral CLP with maxillary hypoplasia CLP with maxillary hypoplasia Mean T SD

16 12 14 12 12 11 11 14 12 11 12 14 13 20 15 13.07 T 2.28

14 8 8 24.5 14 10 13 15 19.5 12 21.5 11.5 14.5 17 14 14.46 T 4.65

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

F indicates female; M, male.

Exclusion Criteria a. Syndromic cases b. Stained cephalograms that were not manually traceable All the included cases had undergone presurgical orthodontics that included arch expansion with HYREX appliance or Quadhelix and removal of compensation by fixed orthodontic mechanotherapy using 018 Roth preadjusted edgewise appliance. The arches were aligned and made compatible to their respective arches. Lateral cephalograms were recorded in natural head position using standardized technique at the end of presurgical orthodontics (C1) Figure 1. Flat occlusal coverage splints with transpalatal bar and hooks in the canine region were cemented on the maxillary arch to secure the maxilla as 1 piece and to facilitate unhindered advancement as a part of surgical preparation. All the cases underwent high-level Le Fort I osteotomy under general anesthesia and placement of RED (KLS Martin, Germany) as per established protocol. A 3-holed miniYbone plate bent at an angle of 45 degrees approximately was suitably adapted and secured with mini screws in the region of piriform aperture. Two twisted SS wires secured

to the free end of the plate and the wire drawn transnasally and attached to distraction cylinders (Figs. 2 and 3). A latency period of 5 days and 0.5-mm twice-a-day rhythm and rate of distraction were followed in all the cases. The maxilla was distracted sagittally until a 4-mm positive overjet was achieved. Consolidation period of 8 to 12 weeks was followed in all cases. At the end of consolidation phase, the RED device was removed under local anesthesia and sedation. Lateral cephalograms were recorded in natural head position, 1 week after the removal of RED (C2) (Fig. 4). An orthodontic face mask was used after consolidation period for 6 months. Elastic stretch of 200 to 250 g of force was applied with face mask using elastics. Postsurgical orthodontics involved fine tuning and settling of occlusion. Lateral cephalograms were recorded 12 months after the consolidation phase (C3) (Fig. 5). Single individual manually performed all the composite tracing. Ten cephalograms were traced after a gap of a week to ensure anatomic point placement reproducibility (J = 0.90). The various cephalometric landmarks, reference points, and linear and angular measurements used in the study are depicted in Figure 6. The database was created on MS Excel worksheet.

RESULTS The descriptive statistics for all the hard tissue and soft tissue cephalometric variables are depicted in Table 2 and Figures 7 and 8. The study sample was composed of 12 cases of operated UCLP. The

FIGURE 1. Preoperative photograph and C1.

144

FIGURE 2. Le Fort I osteotomy and RED in situ.

* 2014 Mutaz B. Habal, MD




Cleft Maxillary Hypoplasia Treated by RED

FIGURE 3. Intraoperative view showing miniplates with traction wires.

age profile of the study subjects was 12 to 20 years (mean, 13.07 T 2.28 years). Eight were males, and 7 were females. Comparison of hard tissue cephalometric variables (Table 3) recorded at the end of presurgical orthodontics (C1) and 1 week after consolidation stage (C2) showed statistically very highly significant (P G 0.0001) difference for SNA, ANB, Co-A, ANS-Me:Na-Me ratio, upper incisor to N vertical. As expected, SNB did not show any statistically significant difference (P = 0.164). The effective distraction executed and achieved in the study sample was 8 to 24.5 mm. Comparison of soft tissue parameters (Table 4) with respect to lateral cephalograms recorded at the C1 and C2 stage showed statistically very highly significant difference (P G 0.0001) for facial contour angle, nasolabial angle, upper lip to E-line, and lower lip to E-line. Comparative evaluation of lateral cephalograms recorded at the C1 and C3 stage showed very highly significant difference (P G 0.0001) for hard tissue variables SNA, ANB, Co-A, ANSMe:Na-Me %, upper incisor to N perpendicular, and all the soft tissue variables studied. There was no significant difference (P 9 0.0001) with respect to variable SNB. Comparative evaluation of lateral cephalograms recorded at the C2 and C3 stage showed very highly significant difference (P G 0.0001) for hard tissue variables except SNB (P = 0.096). Very highly significant (P G 0.0001) difference for soft tissue variables facial contour angle, ULYE-line, LLYE-line, and highly significant (P = 0.028) for nasolabial angle. The percentage difference of measurements for cephalometric variables (C2 vs C3) depicted relapse amounted to 13.72% at SNA, 13.3% at ANB, 9.83% for maxillary depth, 8.99% for the distance of the upper incisor to

FIGURE 4. Postconsolidation photograph and C2.

N perpendicular and 20.73% for facial contour angle, 2.16% for nasolabial angle, 25.69% for distance of UL to E-line, and 25.12% for distance of LL to E-line.

DISCUSSION Since the successful development of RED for cleft maxillary hypoplasia by Polley and Figueroa,5 numerous studies have been published in the literatures that are predominantly case series concluding aesthetic outcomes and clinical difficulties and modifications.6Y9 There are very few studies that have quantitatively analyzed hard and soft tissue changes and evaluated the amount of relapse. A landmark study has been reported by Suzuki et al10 on longitudinal dentoskeletal changes in UCLP cases following maxillary DO using RED system. In their study, 12 Japanese UCLP patients underwent maxillary distraction at the mean age of 16.4 years. They reported significant dentoskeletal relapse during the first 6 months’ follow-up period. In our study, we have observed significant changes in 4 of 5 variables, namely, SNA, SNB, ANB, effective maxillary length at the end of distraction, and 12 months following the removal of distractor. We have observed significant relapse at the end of 12 months’ period, which is in variance with the previously cited study wherein relapse has been observed only in the first 6 months. Gursoy et al11 in a 5-year follow-up study of maxillary DO in dentofacial structures in CLP cases observed a significant horizontal advancement and downward movement of the maxilla with changes seen in SNA and ANB (13 degrees), at maxillary points A, ANS, and PNS. Our study also shows an effective increase in the

FIGURE 5. Postoperative at 12 months and C3.



145


Sahoo et al


FIGURE 6. Cephalogram readings.

maxillary horizontal position approximately by 8 degrees in SNA and improvement of ANB by 3.7 degrees.11 Gursoy et al11 also observed during their 5-year follow-up study that achieved dentoskeletal changes

TABLE 2. Mean Values C1 Mean T SD

Cephalometric Variables Hard tissue SNA SNB ANB Maxillary depth LAFH:AFH (ANS-Me:Na-Me), * % Distance of maxillary incisor to N-A line, mm Soft tissue Facial contour angle Nasolabial angle UL to E-line LL to E-line

146

C2 Mean T SD

C3 Mean T SD

72 T 1.89 82.2 T 1.26 80.8 T 0.94 78.46 T 0.74 78.33 T 0.72 78 T 0 j6.2 T 1.78 3.86 T 1.06 2.53 T 0.83 78.2 T 3.17 87.66 T 1.84 86.73 T 1.75 52.33 T 1.72 63.26 T 1.53 63.26 T 1.53 j5.26 T 1.38 2.86 T 0.83 2.13 T 0.83

4.33 (1.23) j11.6 T 1.54 77.67 (1.45) 98.87 T 3.16 j7.93 (1.03) j4.7 T 0.7 1.2 (1.03) j2.9 T 0.52

j10.3 T 1.75 98.47 T 3.11 j3.87 T 0.74 j1.87 T 0.52

FIGURE 7. Bar chart: mean values of hard tissue variables.





Cleft Maxillary Hypoplasia Treated by RED

FIGURE 8. Bar chart: mean values of soft tissue variables.

partially diminished. The horizontal relapse observed in our study was, namely, SNA 13.72%, ANB 13.3%, effective maxillary length (Co-A) 9.83%, and distance upper incisor to N perpendicular 8.99%. Ko et al12 reported using the same distraction protocol as used in the present study also reported a significant horizontal relapse of 12.6% from 4 to 12 months after the surgery. When vertical relapse was analyzed indirectly using the lower anterior facial height to anterior facial height ratio, we observed no significant long-term changes. Mean vertical relapse to the tune of 53.7% has been reported by Suzuki et al.10 However, we did not observe any significant changes at the end of our observation period. The changes in the distance of the upper incisor to N-A line at C2 after the consolidation phase and C3 observation period were significant denoting relapse in the incisor position. This we feel cannot be attributed to any dental movement as the cause of relapse as the entire maxillary arch was secured as 1 unit with a customized full-coverage splint stabilized using cross-arch stabilization with rigid wires. Change in the readings can be attributed to more change

in point A due to horizontal relapse of maxilla per se. Effective mandibular length could be accounted for adding up to the inference of significant horizontal maxillary relapse. Our study is therefore in agreement with the above studies with respect to the horizontal relapse of maxilla in the short observation period.10Y12 In our study, we have considered lateral cephalograms recorded 1 year following consolidation phase. However, we have been monitoring cases treated in 2007 to 2008, that is, around 5 years, and we observed significant relapse of sagittal maxillary correction, which was compounded by residual mandibular growth. Sagittal maxillary growth ceases by 12 to 14 years; thus, addressing the deficient maxilla around or after this period is prudent, and literature also recommends the same. In cases showing gross maxillary deficiency (GOSLON IV, V),13 early intervention, that is, following secondary alveolar grafting, merits consideration in view of psychological well-being and aesthetic and functional concerns. Requirement of secondary surgical intervention would be there, but the rate expected is minimal. In our series, we felt the need for secondary surgical intervention

TABLE 3. Comparison of the Hard Tissue Parameters

SNA

SNB

ANB

Maxillary depth

LAFH:AFH (ANS-Me:Na-Me),* %

Distance of maxillary incisor to N-A line, mm

C1 C1 C2 C1 C1 C2 C1 C1 C2 C1 C1 C2 C1 C1 C2 C1 C1 C2

vs vs vs vs vs vs vs vs vs vs vs vs vs vs vs vs vs vs

C2 C3 C3 C2 C3 C3 C2 C3 C3 C2 C3 C3 C2 C3 C3 C2 C3 C3

t

P

Remarks

21.7 21.7 10.69 1.47 2.43 1.78 24.68 23.93 8.37 15.17 12.51 3.11 16.09 16.09 V 31.8 25.56 6.2

0.0001 0.0001 0.0001 0.164 0.029 0.096 0.0001 0.0001 0.0001 0.0001 0.0001 0.008 0.0001 0.0001 V 0.0001 0.0001 0.0001

Very highly significant Very highly significant Very highly significant Not significant Significant Not significant Very highly significant Very highly significant Very highly significant Very highly significant Very highly significant Highly significant Very highly significant Very highly significant C2 and C3 values identical Very highly significant Very highly significant Very highly significant

Because all values of SNB (C3) are equal to 78, C1 vs C2 and C2 vs C3 are equivalent to a single sample test K = K0 vs K m K0, where K0 = 78.



147


Sahoo et al


TABLE 4. Comparison of the Soft Tissue Parameters

Facial contour angle

Nasolabial angle

UL to E-line

LL to E-line

C1 C1 C2 C1 C1 C2 C1 C1 C2 C1 C1 C2

vs vs vs vs vs vs vs vs vs vs vs vs

C2 C3 C3 C2 C3 C3 C2 C3 C3 C2 C3 C3

t

P

Remarks

35.24 30.26 10.72 27.33 28.18 2.45 10.81 14.32 9.54 14.32 10.8 *

0.0001 0.0001 0.0001 0.0001 0.0001 0.028 0.0001 0.0001 0.0001 0.0001 0.0001 *

Very highly significant Very highly significant Very highly significant Very highly significant Very highly significant Highly significant Very highly significant Very highly significant Very highly significant Very highly significant Very highly significant

*For distance from LL to E-line, C2 vs C3 1-way analysis of variance is applied as paired t test is NA as all difference = j1. P = 0.0001 (very highly significant).

in 3 cases (20%) due to relapse and mandibular growth. Incidentally, we observed that the cases that underwent larger amount of DO were found to be susceptible to increased quantum of relapse. Mandibular growth continues much longer after maxillary growth due to cephalocaudal gradient. In all our cases, we have overcorrected the maxilla to cater for relapse and residual mandibular growth. This could be the reason for the need for minimal number of secondary surgical intervention. Krimmel et al14 reported the stability in the first year but a decrease in ANB angle during 2- to 5-year follow-up period. Figueroa et al15 also noted a decrease in SNA angle in their 3-year follow-up study. Thus, there is requirement to observe for the continuing relapse in the horizontal direction over a long period. Merits of DO over the orthognathic surgery had always been propagated in various published literature.16 We observed a mean enhancement in the soft tissue parameters at the end of distraction. Soft tissue relapse was also significant but was much more than the changes in the hard tissue parameters. Significant relapse in the soft tissue parameters compared with the hard issue parameters implies that there were more changes in the aesthetic outcome. Similar consensus has been drawn by Wen-Ching et al17 in a study sample of 16 cases treated by RED. Our study has predominantly evaluated relapse in the horizontal dimension. Therefore, we conclude that there is a need to study changes in vertical dimension as well as three-dimensional probably using better imaging modalities.18

CONCLUSIONS Considering the previously mentioned observations, we may conclude that DO by RED has overall improvement in the treatment outcome in the short term in the management of severe cleft maxillary hypoplasia. The challenges to overcome relapse remain. Factoring in the relapse percentage during treatment planning may be one of the options. However, factors such as scarring and its effects due to primary surgeries merit evaluation.

REFERENCES 1. Proffit W, Fields H, Sarver D. Late stages of development. In: Proffit W, Fields H, Sarver D, eds. Contemporary Orthodontics. 4th ed. St Louis, MO: Mosby Inc; 2007:107Y129 2. Spalding PM. Spalding. Craniofacial growth and development: current understanding and clinical considerations. In: Milero M, ed. Peterson’s Principles of Oral and Maxillofacial Surgery. 2nd ed. Hamilton, Ontario, Canada: BC Decker Inc, 2004:1051Y1086 3. Block MS, Brister GD. Use of distraction osteogenesis for maxillary advancement: preliminary results. J Oral Maxillofac Surg 1994;52:282Y286

148

4. Rachmiel A, Jackson IT, Potparic Z, et al. Midface advancement in sheep by gradual distraction: a 1-year follow-up study. J Oral Maxillofac Surg 1995;53:525 5. Polley JW, Figueroa AA. Management of severe maxillary deficiency in childhood and adolescence through distraction osteogenesis with an external adjustable rigid distraction device. J Craniofac Surg 1997;8:181Y185 6. Friedman CD, Constantino PD. Use of distraction osteogenesis for maxillary advancement: preliminary results [discussion]. J Oral Maxillofac Surg 1994;52:287 7. Drew SJ. Maxillary advancement with distraction osteogenesis by use of a rigid external distraction device: a 1-year follow-up [discussion]. J Oral Maxillofac Surg 2000;58:969 8. Swennen G, Colle F, de Mey A, et al. Maxillary distraction in cleft lip palate patients: review of six cases. J Craniofac Surg 1999;5:79Y98 9. Sennen G, Figueroa AA, Schierle H, et al. Maxillary distraction. J Craniofac Surg 2000;11:312Y317 10. Suzuki EY, Motohashi N, Ohyama K. Longitudinal dento-skeletal changes in UCLP patients following maxillary distraction osteogenesis using RED system. J Med Dent Sci 2004;51:27Y33 11. Gursoy S, Hukki J, Hurmerinta K. Five-year follow-up of maxillary distraction osteogenesis on the dentofacial structures of children with cleft lip and palate. J Oral Maxillofac Surg 2010;68:744Y750 12. Ko EW, Figueroa AA, Polley JW. Soft tissue profile changes after maxillary advancement with distraction osteogenesis by use of rigid external distraction device: a 1-year follow-up. J Oral Maxillofac Surg 2000;58:959Y969 13. Ozawa TO, Shaw WC, Katsaros C, et al. A new yardstick for rating dental arch relationship in patients with complete bilateral cleft lip and palate. Cleft Palate Craniofac J 2011;48:167Y172 14. Krimmel M, Cornelius CP, Roser M, et al. External distraction of maxilla in patients with craniofacial dysplasia. J Craniofacial Surg 2001;12:458Y463 15. Figueroa AA, Polley JW, Friede H, et al. Long-term skeletal stability after maxillary advancement with distraction osteogenesis using a rigid external distraction device in cleft maxillary deformities. Plast Reconstr Surg 2004;114:1382Y1392 16. Hierl T. Lengthening the maxilla by distraction osteogenesis. In: Bell WH, Guerrero CA, eds. Distraction Osteogenesis of the Facial Skeleton. 1st ed. Hamilton, Ontario, Canada: BC Decker Inc, 2007:273Y284 17. Wen-Ching Ko E, Figueroa AA, Polley JW. Soft tissue profile changes after maxillary advancement with distraction osteogenesis by use of a rigid external distraction device: a 1-year follow-up. J Oral Maxillofac Surg 2000;58:959Y969 18. Cevidanes LHS, Bailey LJ, Tucker GR Jr, et al. Superimposition of 3D cone-beam CT models of orthognathic surgery patients. Dentomaxillofac Radiol 2005;34:369Y375



Maxillary distraction osteogenesis in cleft lip and palate cases with midface hypoplasia using rigid external distractor: an alternative technique.

Evaluation of the hard and soft tissue changes after maxillary advancement with rigid external distractor in unilateral cleft lip and palate induced maxillary hypoplasia.

Maxillary Distraction Osteogenesis Using a Rigid External Distractor: Which Clinical Factors Are Related With Relapse?

Velopharyngeal changes after maxillary distraction in cleft patients using a rigid external distraction device: A retrospective study.

Maxillary movement in cleft patients treated with internal tooth borne distractor.

Anterior maxillary segmental distraction in the treatment of severe maxillary hypoplasia secondary to cleft lip and palate.

Maxillary hypoplasia in the cleft patient: contribution of orthodontic dental space closure to orthognathic surgery.

Treatment Approach for Maxillary Hypoplasia in Cleft Patients: Class III Elastics with Skeletal Anchorage (Report of Two Cases).

Lateral incisor agenesis predicts maxillary hypoplasia and Le Fort I advancement surgery in cleft patients.

Bilateral maxillary sinus hypoplasia.

Evaluation of functional and esthetic outcome after correction of mandibular hypoplasia secondary to temporomandibular ankylosis treated by distraction osteogenesis.

Rapid maxillary expansion in the primary and mixed dentitions: a cephalometric evaluation.

Cephalometric variables used to predict the success of interceptive treatment with rapid maxillary expansion and face mask. A longitudinal study.

Velopharyngeal Configuration Changes Following Le Fort I Osteotomy With Maxillary Advancement in Patients With Cleft Lip and Palate: A Cephalometric Study.

A long-term clinical and cephalometric study of cleft lip and palate patients following intraoral maxillary quadrangular le fort I osteotomy.

Cephalometric analysis of maxillofacial morphology in unoperated cleft palate patients.

Maxillary sinus hypoplasia masquerading as chronic sinusitis.

Nasal Profile Changes Following Anterior Maxillary Segmental Osteotomy: A Lateral Cephalometric Study.

Estimation of maxillary alveolar cleft volume by three-dimensional CT.

Erratum to: Nasal Profile Changes Following Anterior Maxillary Segmental Osteotomy: A Lateral Cephalometric Study.

Evaluation of transverse maxillary expansion after a segmental posterior subapical maxillary osteotomy in cleft lip and palate patients with severe collapse of the lateral maxillary segments.

A Novel Technique To Correct Multiplanar Maxillary Hypoplasia.

Radiographic evaluation of orthodontic treatment by means of four different cephalometric superimposition methods.

External septorhinoplasty in the cleft lip nose.