The effect of alar cinch sutures and V-Y closure versus. simple closing sutures after Le Fort I osteotomies on. nasolabial esthetics and dynamics

Transcription

1 The effect of alar cinch sutures and V-Y closure versus simple closing sutures after Le Fort I osteotomies on nasolabial esthetics and dynamics Marvick SM Muradin

2 Cover design: ISBN: Layout and printed by: Gildeprint Drukkerijen - Enschede, the Netherlands

3 The effect of alar cinch sutures and V-Y closure versus simple closing sutures after Le Fort I osteotomies on nasolabial esthetics and dynamics (with a summary in English) Het effect van alar cinch sutures en V-Y sluiting versus doorlopende mucosale hechtingen na Le Fort I osteotomieen op de nasolabiale esthetiek en dynamiek (met een samenvatting in het Nederlands) Proefschrift ter verkrijging van de graad van doctor aan de Universiteit Utrecht op gezag van de rector magnificus, prof.dr. J.C. Stoof, ingevolge het besluit van het college voor promoties in het openbaar te verdedigen op dinsdag 22 juni 2010 des ochtends te uur door Marvick Sadied Moestaghesuzaman Muradin geboren op 28 november 1969 te Leiden

4 Promotoren: Prof. dr. R. Koole Prof. dr. P.J.W. Stoelinga Co-promotor: Dr. A.J.W.P. Rosenberg

5 Manuscriptcommissie: Prof. dr. M. Kon Mw prof. dr. Y. Ren Prof. dr. P.E. Haers Prof. dr. S.J. Bergé Prof. dr. D.B. Tuinzing

6 Paranimfen: S.P.E. Poelsma R.M.S. Polsbroek

7 Im Ganzen habe ich jedenfalls erreicht, was ich erreichen wollte. Man sage nicht, es waere der Muehe nicht wert gewesen. Im Uebrigen will ich keines Menschen Urteil, ich will nur Kentnisse verbreiten, ich berichte nur. Franz Kafka, Ein Bericht fuer eine Akademie. Whether you take the doughnut hole as a blank space or as an entity unto itself is a purely methaphysical question and does not affect the taste of the doughnut itself one bit. Haruki Murakami, A wild sheep chase. Ter nagedachtenis aan mijn grootouders, die zich ieder op hun wijze hebben ingezet voor de wetenschap. Voor Pauline, Frederik en Saskia

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9 Contents chapter 1: Introduction and aims of the study 11 chapter 2: Nasolabial esthetics after Le Fort I osteotomy and V-Y closure: 25 A statistical evaluation Int J Adult Orthod Orthognath Surg 2002; 17: chapter 3: A prospective study on the effect of modified alar cinch 45 sutures and V-Y closure versus simple closing sutures on nasolabial changes after Le Fort I intrusion and advancement osteotomies J Oral and Maxillofac Surg 2010, accepted for publication chapter 4: The reliability of frontal facial photographs to assess 59 changes in nasolabial soft tissues Int J Oral Maxillofac Surg 2007; 36: chapter 5: The effect of alar cinch sutures and V-Y closure on soft 81 tissue dynamics after Le Fort I intrusion osteotomies: a preliminary study on 22 patients J Cranio-Maxillofac Surg 2009; 37: chapter 6: The influence of a Le Fort I impaction and advancement 95 osteotomy on smile using a modified alar cinch suture and V-Y closure: a prospective study on 56 patients Int J Oral Maxillofac Surg 2010 submitted chapter 7: Summary, address to the aims, conclusion and 111 future perspectives

10 chapter 8: Samenvatting en evaluatie van de doelstellingen, 119 conclusie en toekomstperspectief. Dankwoord 129 Curriculum vitae 137 List of publications 140 Addendum 141

11 Chapter1 General introduction and aims of the study

12 Chapter 1 The movements of expression in the face and body, whatever their origin may have been, are in themselves of much importance to our welfare. Charles Darwin, The Expression of the Emotions in Man and Animals. 12

13 General introduction Till present, most research concerning orthognathic surgery was focused on items such as, improvement of occlusion 1-4, skeletal stability 3,5-19, facial harmony 4,20-37 and condylar resorption Facial harmony and dynamics are, however, important in human interaction. Particular smiling, as a facial expression, is thought to be socially very important. This is indicated by the fact that people tend to smile, when engaged in a social interaction, rather than when they are solitarily experiencing a pleasant emotion 47. Maxillofacial surgeons are able to change both, facial features and dynamics. We, therefore, should understand which interventions cause what specific effect on facial features and dynamics. The present study aims at describing the dynamics of the perioral musculature, that are often affected by orthognathic surgery and in particular by osteotomies of the maxilla. The dynamics of these muscles have a direct relationship with facial expression, which comes into play when expressing certain moods or feelings. The perioral muscles are also important for functions such as, laughing, smiling, sucking, swallowing, phonating and kissing. The above mentioned functions are important for the self esteem of a patient, but above all play an important role in our social interactions. According to Goldstein 48 and McKelvie 49 people tend to look at the eyes, mouth and nose, in that order, when they judge new acquaintances. It appears that our attention is mainly focused on the mouth and eyes when communicating with other persons 50,51. And in Western cultures, especially, the emphasis, when judging emotions, lies on the mouth 52. For this reason, orthognathic surgery should not only aim at facial harmony, but also on the possible changes in the dynamics of the relevant muscles, as a result of surgery. The mimic muscles of the mid- and lower face consist of three muscular rings including, the nasal, oral and mental ring. The muscular fibers of these rings (sphincters) are closely connected which each other (Fig. 1-1). The nasal sphincter mainly consists of the nasal muscles, which run from the middle of the nasal bones in a caudal direction lateral of the alar crus, where they intertwine with the fibers of the levator labii alaeque nasi, levator labii superioris and zygomatic 13

14 Chapter 1 minor muscles. From there the fibers run along the nasal aperture, inserting on the nasal septum, anterior nasal spine and philtral ridge. At this ridge they merge with the fibers of the orbicularis oris and depressor anguli oris muscles. The oral ring or sphincter consists of the orbicularis oris muscle, which has a superficial and a deep part. This is necessary for its complex function The upper part of the superficial fibers of the orbicularis oris muscle merges with those from the paranasal muscles, running along the philtral crests to insert at the anterior nasal spine and septum, mingling with the depressor septi fibers (Fig. 1-2A). Short fibers of the lower part of the superficial portion of the orbicularis oris muscle insert into the skin of the upper lip on the ipsilateral side, long fibers on the contralateral side, contributing to the formation of the philtral ridges as they mingle with the fibers of the paranasal and depressor anguli oris muscles (Fig. 1-2B). The deep part of the orbicularis oris muscle consists of a peripheral and a marginal portion (Fig. 1-2C). The fibers of the marginal portion run from one modiolus to the other. The fibers of the peripheral portion of the deep orbicularis muscle run from the modiulus to the contralateral incisive fossa. Contraction of the deep part of the orbicularis, seals the lips. The superficial part merges with the extrinsic facial muscles and, thus, assists in opening of the mouth. When the lips are pursed up, or pouting, the vermillion becomes thickened as the marginal portion of the deep orbicularis oris muscle contracts. Because the fibers of the peripheral portion are attached to the incisival fossa, the pouting effect becomes visible. Simultaneous relaxation of the superficial part of the orbicularis oris muscle produces perioral wrinkles, accentuates the philtral ridges and flattens the nasolabial folds. 14

15 General introduction Figure 1-1. Anatomy of the nasal and oral musculature: I upper ring, II middel ring, III lower ring. 1. Nasalis; 2. Levator labii superioris alaeque nasi; 3. Nasal septum; 4. Levator labii superioris; 5. Zygomaticus major; 6. Alar cartilage; 7. Zygomaticus minor; 8. Levator anguli oris; 9. Orbicularis oris, pars superficialis; 10. Orbicularis oris, pars profunda; 11. Buccinatorius; 12. Depressor anguli oris; 13. Depressor labii inferioris; 14. Mentalis. Not shown: Depressor septi, Risorius, Platysma. When the mouth is open, perioral wrinkles and philtral ridges are flattened, as contraction of the superficial orbicularis oris muscle stretches the perioral skin. During this action, however, the nasolabial folds become more accentuated. Simultaneous relaxation of the deep portion decreases the thickness of the vermillion. 15

16 Chapter 1 Fig 1-2. A. Frontal view of the fibers of the superficial (SOO) and deep (DOO) orbicularis muscle. B. Transversal section of the upper lip: Short and long fibers of the superficial orbicularis oris muscle forming the philtral ridges.c. Sagittal section of the upper lip: The orbicularis oris muscle has two components. A superficial part (SOO) and a deep part. The deep part of the orbicularis oris has two portions, a marginal (MDOO) and a peripheral one (PDOO). The lower facial sphincter consists of the mental muscle, originating from the juga alveolaria of the central incisors, the depressor anguli oris muscle, originating from the inferior border of the mandible, the depressor labii inferioris muscle, originating from the area around the mental foramina and the merging fibers of the platysm muscle, originating from the clavicle. The ring-form of this sphincter is accentuated in persons having a central dimple of the chin, because they have a mentalis muscle that is split in to two separate parts. The upper part of the mentalis muscle runs from the alveolar jugae, at the area of the central incisors and merges at its insertion with the orbicularis oris muscle. The lower part inserts at the skin of the chin. Two muscles, that also play a role in relation to oral function and contribute to the oral and lower sphicter, are the buccinator and risorius muscles. The buccinator originates from the pterygomandibular raphe and the alveolar process, in the molar area of both jaws and inserts at the corners of the mouth, hereby merging with the orbicularis oris muscle. The risorius muscle is thought to be part of the platysm muscle, a finding of Santorini in

17 General introduction The detrimental effect of the loss of the insertions of the above mentioned muscles on esthetics and function, is seen after alveolar bone loss, following loss of all teeth in both jaws In order to get access to the maxilla, to carry out an osteotomy, a vestibular incision has to be made, which also cuts through the attachments on the premaxilla of the orbicularis oris-, nasalis-, depressor septi and levator labii alaeque nasi muscles. In addition, degloving has to be done to free the paranasal area. This will sever the origins and insertions of parts of the nasal and oral sphincter. The detached muscles will have a tendency to contract. When, after the osteotomy, the incisions are closed by means of a simple running suture, i.e. through the mucosa only, the detached and contracted muscles are not in their original position and most likely will re-insert at a higher, more lateral, position 64,65. This may affect the functions as mentioned above. In previous studies 64,66,67 a muco-musculo-periosteal V-Y closure of the vestibular incision was recommended to counteract possible unwanted effects on the upper lip. To prevent excessive broadening of the nose a combination of the V-Y closure with an alar cinch suture was advised 67,68. A classic alar cinch suture rotates the alar crurae in a counterclockwise direction, which may lead to upwards nasal tip rotation. In order to prevent this and to restore the vector of the paranasal and labial muscles in a correct anatomical position, the alar cinch suture was modified. The modification includes a 2x0 Vicryl suture through the levator and nasal muscles, including the periosteum, and passed through the nasal septum, approximately 10 mm posterior to the anterior nasal spine. After passing the paranasal muscles and periosteum, the suture is run back through the nasal septum again to the original entrance side and tied (Fig. 1-3.) 17

18 Chapter 1 Figure 1-3. Transseptal alar cinch suture In this study, it is proposed that for a proper restoration of the labial functions, additional to the V-Y closure, an alar cinch suture is mandatory. For this reason the aims of this study are: What was the effect on the nasolabial profile of a simple V-Y closure after Le Fort I osteotomies? (chapter 2) Does a modified alar cinch suture, combined wih a V-Y closure, improve the nasolabial profile after Le Fort I osteotomies? (chapter 3) Does a modified alar cinch suture, combined with V-Y closure, prevent excessive nasal tip upwards rotation? (chapter 3) Is standardized photogrammetry a reliable method to analyze changes in the nasolabial dynamics? (chapter 4) Does a modified alar cinch suture, combined with a V-Y closure, have a different effect on nasolabial dynamics, as compared to simple closing sutures after Le Fort I osteotomies? (chapter 5) Are the nasolabial dynamics in patients with a vertical maxillary hyperplasia different from persons with a normal inter-maxillary relationship? (chapter 6) Does a modified alar cinch suture, combined with V-Y closure, improve the nasolabial dynamics after Le Fort I osteotomies? (chapter 6) 18

19 General introduction References 1. Tompach P, Wheeler J, Fridrich K: Orthodontic considerations in orthognathic surgery. Int J Adult Orthod Orthognath Surg 10:97, Hoppenreijs T, van der Linden F, Freihofer H, van t Hof A, Tuinzing D, Voorsmit R, Stoelinga P: Occlusional and functional conditions after surgical correction of anterior open bite deformities. Int J Oral Maxillofac Surg 25:29, Hoppenreijs T, Freihofer H, Stoelinga P, Tuinzing D, van t Hof A, van der Linden F, Nottet S: Skeletal and dento-alveolar stability of Le Fort I intrusion osteotomies and bimaxillary osteotomies in anterior open bite deformities: A retrospective threecentre study. Int J Oral Maxillofac Surg 26:161, Sarver D, Ackerman J: Orthodontics about face: The re-emergence of esthetic paradigm (editorial). Am J Orthod Dentofac Orthop 117:575, Schendel SA, Eisenfeld JH, Bell WH, Epker BN: Superior repositioning of the maxilla: stability and soft tissue osseous relations. Am J Orthod 70:663, Hedemark A, Freihofer H: The behavior of the maxilla in vertical movements after LeFort I osteotomy. J Maxillofac Surg 6:244, Brammer J, Finn R, Bell W, Sinn D, Reisch J, Dana K: Stability after bimaxillary surgery to correct vertical maxillary excess and mandibular deficiency. J Oral Surg 38:664, LaBanc J, Turvey T, Epker BN: Results following simultaneous mobilization of the maxilla and mandible for the correction of dentofacial deformities: analysis of 100 consecutive cases. Oral Surg 54:607, Greebe R, Tuinzing D: Superior repositioning of the maxilla by a Le Fort I osteotomy: A review of 26 patients. Oral Surg Med Oral Pathol 63:158, Proffit W, Phillips C, Turvey T: Stability following superior repositioning of the maxilla by Le Fort I osteotomy. Am J Orthod Dentofac Orthop 92:151, Krekmanov L, Lilja J, Ringqvist M: Simultaneous correction of maxillary and mandibular dentofacial deformities without the use of postoperative intermaxillary fixation. Int J Oral Maxillofac Surg 17:363, Welch T: Stability in the correction of dentofacial deformities: a comprehensive review. J Oral Maxillofac Surg 47:1142,

20 Chapter Haymond C, Stoelinga P, Blijdorp P, Leenen R, Merkens N: Surgical orthodontic treatment of anterior skeletal open bite using small plate internal fixation. Int J Oral Maxillofac Surg 20:223, Bishara S, Chu G: Comparisons of postsurgical stability of the Le Fort I maxillary impaction and maxillary advancement. Am J Orthod Dentofac Orthop 102:335, Bailey L, Phillips C, Proffit W, Turvey T: Stability following superior repositioning of the maxilla by Le Fort I osteotomy: five-year follow-up. Int J Adult Orthod Orthognath Surg 9:163, Proffit W, Turvey T, Phillips C: Orthognathic surgery: a hierarchy of stability. Int J Adult Orthod Orthognath Surg 11:191, Emshoff R, Scheiderbauer A, Gerhard S, Norer B: Stability after rigid fixation of simultaneous maxillary impaction and mandibular advancement osteotomies. Int J Oral Maxillofac Surg 32:137, Norholt S, Pedersen T, Jensen J: Le Fort I miniplate osteosynthesis: a randomized prospective study comparing resorbable PLLA/PGA with titanium. Int J Oral Maxillofac Surg 33:245, Ueki K, Marukawa K, Shimada M, Nakagawa K, Alam S, Yamamoto E: Maxillary stability following Le Fort I osteotomy in combination with sagittal split ramus osteotomy and intraoral vertical ramus osteotomy: a comparative study between titanium miniplate and poly-l-lactic acid plate. J Oral Maxillofac Surg 64:74, Burstone C: Lip posture and its significance in treatment planning. Am J Orthod 53:262, Burstone C, Legan H: Cephalometrics for orthognathic surgery. J Oral Surg 36:269, Legan H, Burstone C: Soft tissue cephalometric analysis for orthognathic surgery. J Oral Surg 38:744, Epker BN, Turvey T, Fish L: Indications for simultaneous mobilization of the maxilla and mandible for the correction of dentofacial deformities. Oral Surg Oral Med Oral Pathol 54:369, Rosen HM: Lip-Nasal Aesthetics Following Le Fort I Osteotomy. Plast Reconstr Surg 81:171, Sarver D, Weissman S: Long-term soft tissue response to Le Fort I maxillary superior repositioning. Angle Orthod 61:268,

21 General introduction 26. Jensen AC, Sinclair PM, Wolford LM: Soft tissue changes associated with double jaw surgery. Am J Orthod Dentofacial Orthop 101:275, McCance AM, Moss JP, Fright WR, James DR, Linney AD: A three dimensional soft tissue analysis of skeletal II patients following bimaxillary surgery. Br J Oral Maxillofac Surg 30:212, Betts NJ, Vig KWL, Vig P, Spalding P, Fonseca RJ: Changes in the nasal and labial soft tissues after surgical repositioning of the maxilla. Int J Adult Orthod Orthognath Surg 8:7, Lee D, Bailey L, Proffit W: Soft tissue changes after superior repositioning of the maxilla with LeFort I osteotomy: 5-year follow-up. Int J Adult Orthod Orthognath Surg 11:301, Lin S-S, Kerr W: Soft and hard tissue changes in Class III patients treated by bimaxillary surgery. Eur J Orthod 20:25, McCollum A, Reyneke J, Wolford L: An alternative for the correction of the Class II low angle mandibular plane angle. Oral Surg Med Oral Pathol 67:231, Proffit W, White J: Who needs surgical-orthodontic treatment? Int J Adult Orthod Orthognath Surg 5:81, Rosen HM: Occlusal plane rotation: aesthetic enhancement in mandibular microgenia. Plast Reconstr Surg 91:1231, Reyneke J: Surgical cephalometric prediction tracing for the alteration of the occlusal plane by means of the rotation of the maxillomandibular complex. Int J Adult Orthod Orthognath Surg 14:55, Mommaerts MY, Lippens F, Abeloos JVS, Neyt LF: Nasal Profile Changes After Maxillary Impaction and Advancement Surgery. J Oral Maxillofac Surg 58:470, McFarlane R, Frydman W, McCabe S, Mamandras A: Identification of nasal morphologic features that indicate susceptibility to nasal tip deflection with the Le Fort I osteotomy. Am J Orthod Dentofac Orthop 107:259, Hajeer MY, Ayoub AF, Millett DT: Three-dimensional assessment of facial soft-tissue asymmetry before and after orthognathic surgery. Br J Oral Maxillofac Surg 42:396, Sesanna E, Raffaini M: Bilateral condylar atrophy after combined osteotomy for correction of mandibular retrusion. J Maxillofac Surg 13:263,

22 Chapter Kerstens H, Tuinzing D, Golding R, van der Kwast W: Condylar atrophy and osteoarthrosis after bimaxillary surgery. Oral Surg Med Oral Pathol 69:274, Herbosa E, Rotskoff K, Ramos B: Condylar position in superior maxillary repositioning and its effect on the temporomandibular joint. J Oral Maxillofac Surg 48:690, Bouwman J, Kerstens H, Tuinzing D: Condylar resorption in orthodontic surgery: the role of intermaxillary fixation. Oral Surg Med Oral Pathol 78:138, Feinerman D, Piecuch J: Long-term effects of orthognathic surgery on temporomandibular joint: comparison of rigid and nonrigid fixation. Int J Oral Maxillofac Surg 24:268, De Clercq C, Abeloos JVS, Mommaerts MY: Temporomandibular joint symptoms in an orthognathic surgery population. J Craniomaxillofac Surg 23:195, Hoppenreijs T, Freihofer H, Stoelinga P, Tuinzing D, van t Hof A: Condylar remodelling and resorption after Le Fort I and bimaxillary osteotomies in patients with anterior open bite: A clinical and radiological study. Int J Oral Maxillofac Surg 27:81, Borstlap W, Stoelinga P, Hoppenreijs T, van t Hof A: Stabilisation of sagittal split advancement osteotomies with miniplates: a prospective, multicentre study with twoyear follow-up. Part III- Condylar remodelling and resorption. Int J Oral Maxillofac Surg 33:649, van Strijen P, Breuning K, Becking A, Tuinzing D: Condylar resorption following distraction osteogenesis: a case report. J Oral Maxillofac Surg 59:1104, Kraut R, Johnston R: Social and emotional messages of smiling: An ethological approach. J Pers and Soc Psychol 37:1539, Goldstein R: Study of need for esthetics in dentistry. J Prosthet Dent 21:589, McKelvie S: The role of eyes and mouth in memory of a face. Am J Psychol 89:311, Thompson L, Malmberg J, Goodell N, Boring R: The distribution of attention across a talker s face. Discourse Processes 38:145, Kano F, Tomonaga M: Face scanning in chimpanzees and humans: continuity and discontinuity. Animal Behaviour 79:227, Yuki M, Maddux W, Masuda T: Are the windows to the soul the same in the East and West? Cultural differences in using the eyes and mouth as cues to recognize emotions in Japan and the United States. J Exp Soc Psychol 43:303,

23 General introduction 53. Delaire J, Feve J, Chateau J, Courtay D, Tulasne J: Anatomie et physiologie des muscles et du frein median de la levre superieure. Revue de Stomalogie et de Chirurgie Maxillo-faciale 78:821, Delaire J: Theoretical Principles and Techniques of Functional Closure of the Lip and Nasal Aperture. J Max Fac Surg 6:109, Nicolau P: The orbicularis oris muscle: a functional approach to its repair in the cleft lip. Br J Plast Surg 36:141, Park C, Ha B: The Importance of Accurate Repair of the Orbicularis Oris Muscle in the Correction of Unilateral Cleft Lip. Plast Reconstr Surg 96:780, Breitsprecher L, Fanghaenel J, Metelmann H-R, Mlynski G, Wuerfel F, Freise K, Knape U: The influence of the muscles of facial expression on the development of the midface and the nose in cleft lip and palate patients. A reflection of functional anatomy, facial esthetics and physiology of the nose. Ann Anat 181:19, Breitsprecher L, Fanghaenel J, Noe A, Lockett E, Raab U: The functional anatomy of the muscles of facial expression in humans with and without Cleft Lip and Palate. A contribution to refine muscle reorientation in primary cheilo- and rhinoplasties in patients with uni- and bilateral CLP. Ann Anat 184:27, Brix M, Ricbourg B, Spitzer W: Phylogenetische Aspekte der Lippenfunktion. Mund Kiefer GesichtsChir 8:28, Cawood J, Howell R: Reconstructive preprosthetic surgery. I. Anatomical considerations. Int J Oral Maxillofac Surg 20:75, Bosker H: The transmandibular implant for mandibular reconstruction. J Oral Maxillofac Surg 49:21, Powers M, Bosker H: Functional cosmetic reconstruction of the facial lower third associated with placement of the transmandibular implant system. J Oral Maxillofac Surg 54:934, Sutton D, Lewis B, Patel M, Cawood J: Changes in facial form relative to progressive atrophy of the edentulous jaws. Int J Oral Maxillofac Surg 33:676, Schendel SA, Williamson LW: Muscle reorientation following superior repositioning of the maxilla. J Oral Maxillofac Surg 41:235, O Ryan FS, Schendel SA: Nasal anatomy and maxillary surgery. II. Unfavorable nasolabial esthetics following the Le Fort I osteotomy. Int J Adult Orthod Orthognath Surg 4:75,

24 Chapter Carlotti AE, Aschaffenberg PH, Schendel SA: Facial changes associated with surgical advancement of the lip and maxilla. J Oral Maxillofac Surg 44:593, O Ryan FS, Schendel SA, Carlotti AE: Nasal anatomy and maxillary surgery. III. Surgical techniques for correction of nasal deformities in patients undergoing maxillary surgery. Int J Adult Orthod Orthognath Surg 4:157, Collins D, Epker B: The alar base cinch: A technique for prevention of alar base flaring secondary to maxillary surgery. Oral Surg Med Oral Pathol 53:549,

25 Chapter2 Nasolabial esthetics after Le Fort I osteotomy and V-Y closure: A statistical evaluation AJWP Rosenberg, MSM Muradin, A vd Bilt Int J Adult Orthod Orthognath Surg 2002; 17: 29-39

26 Chapter 2 Six by nine. Forty two. That s it. That s all there is. I always thought something was fundamentally wrong with the Universe. Douglas Adams, The hitchhiker s guide through the galaxy. This study was presented in Edinburgh, United Kingdom, at the15th Congress of the European Association of Craniomaxillofacial Surgery in September

27 Nasolabial esthetics after Le Fort I osteotomy and V-Y Introduction The Le Fort I osteotomy results in less predictable soft tissue changes, which can be difficult to control because of considerable variation in their adaptation. Adverse changes of the lip and nose including alar flaring, upturning of the nasal tip, and flattening of the lip/nasolabial region may occur, resulting in accentuation of the nasolabial groove, reduced vermilion exposure, and thinning and lateral retraction of the lip, with downturning of the mouth angle. 1 The tip of the nose turns upward, the nasolabial angle might increase, 2 and the maximal alar width increases. 3 5 Some of these changes can also be found in the aging face and should therefore be prevented. Numerous previous reports have discussed the soft tissue changes after Le Fort I osteotomies, but there seems to be controversy over how to control nasolabial esthetics. 6 Several methods can be found in the literature and can be used in combination with each other: alar base cinch suture, 7 partial or total removal of the anterior nasal spine in combination with an alar base cinch suture, 8 V-Y closure of the wound in combination with a suture through the M nasalis, 9 vertical incisions with tunneling on the buccal side. 10 The aim of this descriptive statistical analysis is to correlate the different directions of movements of the maxilla with changes of the soft tissues in cases where only a V-Y plasty in the midline was performed, in order to find out the most efficient direction of movement for this simple procedure. These results will be compared with the results found in the literature. Material and methods Patient selection Of the 134 noncleft patients operated on between 1994 and 1997, 64 well-documented cases were eligible for selection from the files of the Maxillofacial Surgery Department at the University Hospital of Utrecht. Excluded were patients with congenital deformities and patients with prior or concomitant additional midfacial surgery. Also excluded were segmented Le Fort I osteotomies and cases with simultaneously performed mandibular surgery. The selected patients had either a maxillary horizontal deficiency, maxillary vertical deficiency, and/or maxillary vertical excess. Four groups of movements were distinguished: impaction of the maxilla, advancement of the 27

28 Chapter 2 maxilla, combined advancement with impaction of the maxilla, and dorsal impaction of the maxilla. Le Fort I surgery The technique performed was described by Obwegeser 11 and done in the conventional way: The horizontal incision was made high in the vestibule and extended from the second premolar on one side to the second premolar on the other side, subperiosteal degloving including the nasal spine, osteotomy of the lateral wall of the maxillary sinus, and rim of the piriform aperture, separation of the septum, osteotomy between tuber maxillae and the pterygoid plates. The maxilla was fixed with semirigid miniplate osteosynthesis, with or without additional wire osteosynthesis. A V-Y closure in the midline was performed in all cases. The incision was closed with a continuous suture (Vicryl 3.0, Johnson and Johnson, Amersfoort, The Netherlands). In none of these cases was an alar base cinch suture performed, 7 nor was an alar base cinch suture passed through the transverse nasalis muscle and periosteum. 9 The anterior nasal spine was neither remodeled nor removed. Acquisition of data and cephalometric analysis All patients had a full preoperative and postoperative examination, which included the measurement of overbite, overjet, and maximum alar width, an orthopantomogram (OPT), a standardized lateral cephalogram, full photographic documentation, and plaster of paris casts. All patients had received preoperative and postoperative orthodontic treatment. They were followed at regular time intervals: after finishing the preoperative orthodontic treatment, as well as at 3 months and 1 year postoperatively. At these appointments, the same investigations were done as in the preoperative examination. The lateral cephalograms were made at a focus-patient distance of 6 m, and a patient film distance of 0.40 m. The cephalograms were printed on Agfa curix films (Henry Schein bv, Utrecht, The Netherlands). All lateral cephalograms were digitized by one investigator (MSMM) using Dentofacial planner 5.1 (Dentofacial Software, Toronto, Ontario, Canada), using a Hipad digitizer (Houston Instruments, divi sion of Ametek, Belgium) and an ADI microscan computer (ADI computer, Taipei, Taiwan). A custom-made analysis was done for all relevant points that could be found 28

29 Nasolabial esthetics after Le Fort I osteotomy and V-Y through the use of an X-Y system centered in the sella. The x-axis runs from sella through nasion plus 7 degrees, which is a reliable landmark and a good alternative for the Frankfort horizontal line 2 (Fig 2-1). The y-axis runs down from the sella; therefore, the vertical measurements are in the negative part of the X-Y system. Negative values move in a cranial direction and positive values in a caudal direction. Baumrind and Frantz 12 evaluated the reliability of common cephalometric landmarks: Both sella and nasion were rated extremely high. The soft tissue points measured were pronasale (Pn), subnasale (Sn), labrale superior (Ls), and stomion superior (Sts). The bony points measured were A point (A), I point (I), and posterior nasal spine (PNS). The cephalometric points are depicted in Fig 2-1. From every point mentioned, the X direction as well as the Y direction could be determined. When measuring the X direction, the letter x is added; when measuring the Y direction, the letter y is added to the soft or hard tissue points. The differences between the points measured preoperatively and 1 year postoperatively were calculated. The 3-month data were not used because edema might have still been present at that time. Fig A custom-made analysis was created where all relevant points could be used using an X-Y system centered in the sella. The x-axis runs from sella through nasion plus 7 degrees, which is a reliable guide and a good substitute for the Frankfort horizontal line. The y-axis runs down from sella. The vertical measurements are thus in the negative part of the X-Y system. Negative values move in a cranial direction and positive values move in a caudal direction. 29

30 Chapter 2 Methodological error The error of the method was assessed by digitizing the randomly selected lateral cephalograms of 20 patients a second time after 4 months (Table 2-1).The difference between these 2 measurements was considered to be the error of method. X Y Mean error A-point I-point Post nasal spine Subnasale Labrale sup Stomion Table 2-1. Method of error for 20 randomly selected cephalograms digitized a second time (n=20) Final selection criteria Four subgroups were defined: 1. Impaction group. The movement at point Ax had to be less than 2 mm, whereas point Ay had to be greater than 2 mm. This group contained 11 patients. 2. Advancement. The movement at point Ax had to be greater than 2 mm, whereas the movement at point Ay had to be less than 2 mm. This group contained 9 patients. 3. Impaction and advancement. Point Ax had to move more than 2 mm, as did point Ay. This group contained 17 patients. 4. Dorsal impaction. The movement at the posterior nasal spine in the Y direction (PNSy) had to be 2 mm greater than the movement at point Ay. This group contained 14 patients. A total sample of 51 patients in 4 subgroups with similar vectors of movements were thus eligible for selection. Statistical analysis Descriptive statistics were calculated for each landmark covering the preoperative to 1-year postoperative time period. The equation for the regression analysis used was: A = bc + Intercept. 30

31 Nasolabial esthetics after Le Fort I osteotomy and V-Y In this equation, A = the soft tissue changes (dependent variable), C = the movement of the bony point (independent variable), b = the coefficient indicating the percentage of change of the soft tissues after 1 mm of bony movement, and Intercept demonstrates the change of the soft tissue after 0 mm movement of the bone.thus,the intercept demonstrates the changes of the soft tissues by the operation itself. A regression analysis was performed with the bony points A, I, and posterior nasal spine (PNS) as independent variables and the soft tissue points mentioned above as dependent variables. The relationships between the vector of the skeletal movements and changes at labrale in X and Y di rection (Lsx and Lsy), stomion in X and Y direction (Stx and Sty), subnasale in X and Y direction (Snx and Sny), pronasale in X and Y direction (Pnx and Pny), and the maximal alar width (MAW) were described with forward multiple linear regression analysis, and the calculated Pearson correlation coefficients (r). The r 2 value was calculated: an r 2 value of 1 indicates 100% correlation, whereas an r 2 square value of 0 indicates no correlation and thus maximal variation. P values <.05 were considered relevant for formulating a regression equation. In order to find out which were the most relevant bony points, a forward multiple linear regression analysis was performed on the equations with P values < The different bony points that defined 1 soft tissue point were selected. The equation with the bony point with the highest r 2 value was considered the most important independent variable and was therefore selected. This first selection was done on the whole group of 51 patients. Thereafter, the groups were divided in 4 groups with similar vectors of movement as described above. In these 4 subgroups, forward multiple regression analysis was used to select the equation with the highest r 2 value. The statistical package used was SPSS 9 for MS Windows (SPSS, Chicago, IL), using a Dell computer. Results Fifty-one patients were included in this study. The mean age was 24.6 years from a range of 18 to 42 years. There were 31 females and 20 males. The forward multiple regression analysis was used on the group of 51 patients. The different bony points defining each relevant soft tissue point are listed in Table 2-2. The bony point mentioned first for each soft tissue point is the most influential bony 31

32 Chapter 2 point with the highest r 2 and thus the most relevant point for that soft tissue point. All P values < The results of the 4 subgroups will be correlated with the independent bony points. Clinical relevant equations (P < 0.05) are mentioned in Table 2-3. Impaction (n = 11) Mean impaction at A-point was 5.5 mm, whereas point A moved forward only 0.2 mm (SD = 1.1). Thus, in this group near full impaction without advancement was achieved. Dependent Independent 1 r 2 Independent 2 Independent 3 Stsx Ix 0.52 Iy Ax Stsy Ay 0.41 Lsx Ix 0.58 Ax Ay Lsy Ay 0.35 Ix Snx Ax 0.33 Ay Sny Ix 0.19 Ay Pnx Ax 0.21 Ay Pny Ix 0.20 Ay Table 2-2. Forward multiple regression analysis. For each dependent variable, the most influential independent variable is selected first. The second best is selected thereafter. The third best is mentioned in the last column. r 2 value is mentioned only for the first undependent variable. For all equations: P < 0.01, n=51. Labial changes. A significant increase of stomion superior was observed (P = 0.04). The best fitting regression equation for stomion superior was: Stsy = 1.33Ay 1.49 PNSy 0.38 Stsx = 0.80 Ix By every mm upward movement of point A, stomion followed by 1.33 mm. The ratio of PNSy was Hence in impaction cases, the movement slightly lengthened the upper lip. Yet initially there was shortening of the lip, as indicated by the intercept of 0.38, due to the operation itself. Nasal changes. No statistically significant changes of the nose were found in impaction cases. 32

33 Nasolabial esthetics after Le Fort I osteotomy and V-Y r 2 P value Impaction (n= 11) Stsy = 1.33Ay 1.49PNSy Stsx = 0.80Ix Advancement (n= 9) Lsx = 0.65Ix Stsy = -0.33Ix Snx = 0.64Ax Sny = -0.38Ix Pnx =.034Ax Pny = -0.29Ix Impaction and advancement (n= 17) Lsx = 0.34Ix PNSx Lsy = -0.31Ay Iy Stsx = 0.54Ix PNSy Stsy = -0.27Ix Iy Sny = -0.30Ix Dorsal impaction (n= 14) Lsx = 0.47Ax Lsy = 1.23Ay Stsx = 0.47Ax Stsy = 1.12Ay Pnx = 0.46Ax Pny = 1.03Ay Snx = 0.38Ax Sny = 1.19Ay Table 2-3. Regression equations for P < 0.05 using forward multiple regression analysis. If two independent (bony) points define the same variable, the equation with the lowest P value is selected. Advancement (n=9) Mean advancement at A-point (Ax) was 2.6 mm (SD = 1.4). Mean impaction (Ay) was 0.4 mm (SD = 1.5). Labial changes. No significant correlation was found between stomion superior x and A-point. However, statistically significant correlations were found at the position of labrale superior: Lsx = 0.65Ix 0.06 Stsy = 0.33Ix

34 Chapter 2 Thus, for every mm forward movement of Ix, the Lsx moved forward 0.65 mm. There was almost no effect on Lsx of the operation itself as the intercept was nearly zero. Forward movement of I point gave an upward movement of stomion. Hence the decrement of vermilion exposure. Nasal changes. Horizontal movement of the maxilla had several statistically significant effects on the nose. The best fitting regression equations proved to be: Snx = 0.64Ax 0.05 Sny = 0.38Ix Pnx = 0.34Ax Pny = 0.29Ix 0.30 Vertical movements of the soft tissue points of the nose, i.e. Sn and Pn, had a negative coefficient and were influenced by horizontal movements of I-point and A-point. Therefore, the points Sn and Pn moved in a cranial direction. Sn and Pn were significantly influenced by the horizontal movement of A-point. When this independent point moved forward, Sn and Pn did the same to a lesser degree. As in all these equations, the intercept was small; there was no significant influence on the soft tissues by the operation itself. Impaction and advancement (n=l7) Labial changes. The best-fitting equations were: Lsx = 0.34Ix PNSx Lsy = 0.31Ix Iy Stsx = 0.54Ix + 0.3lPNSy Stsy = 0.27Ix Iy For horizontal movements of the maxilla as indicated by I-point and posterior nasal spine, stomion and labrale superior followed to a lesser degree. The intercept showed that the operation itself caused some minor forward movement. Vertical soft tissue movements were influenced by horizontal as well as vertical movements of I-point. 34

35 Nasolabial esthetics after Le Fort I osteotomy and V-Y There was some lip lengthening, as indicated by the intercepts of 0.45 and The vertical changes of labrale superior and stomion superior were almost equally influenced by the bony movements; therefore, vermilion exposure was not changed. The horizontal hard tissue movement influenced the soft tissue changes to a lesser degree than the vertical hard tissue movement, as the ratio coefficients of the former were smaller than those of the latter. Nasal changes. The significant equation that described the nose was: Sny = 0.30Ix 0.71 Dorsal impaction (n=14) Mean impaction at A-point (Ay) was 0.8 mm (SD = 2.1 mm); for the posterior nasal spine (PNSy), impaction was 4.4 mm (SD = 1.9 mm). Advancement at A-point (Ax) was 0.4 mm (SD = 3.0 mm). Labial changes. The best-fitting formulas for changes at the lip are given by: Lsx = 0.47Ax 1.55 Stsx = 0.47Ax 2.06 Lsy = 1.23Ay Stsy = 1.12Ay 0.13 The intercept of the first 2 formulas, describing horizontal changes of labrale superior and stomion superior, was negative; hence there was thinning of the upper lip and loss of lip projection, because the operation itself moved the lip structures in a dorsal direction. However, the ratio coefficient was nearly equal, so the forward movement of A-point had an identical effect on labrale and stomion. The vertical changes of the upper lip initially demonstrated that Ls moved in a caudal direction as the intercept was 1.08, whereas St moved 0.13 mm upward. When A-point moved upward, Ls moved upward more than St because the coefficient of Ls was greater than the ratio coefficient defining for St. Therefore, the potentially resulting loss of vermilion exposure from the operation was counteracted by the upward movement of A-point. 35

36 Chapter 2 Nasal changes. The nasal changes were best illustrated by the following formulas: Snx = 0.38Ax 0.23 Pnx = 0.46Ax 0.67 Pny = 1.03Ay Sny = 1.19Ay Significant nasal changes in cases of dorsal impaction were influenced by A-point. The vertical movement of A-point had a greater ratio coefficient than the horizontal movements. Pn and Sn moved forward and upward, although the operation itself caused some caudal movement, as the intercept was and However, this movement was counteracted by the upward movement of A-point. Maximal alar width In all 4 groups of movement, no statistically significant effects were found regarding the maximal alar width. Discussion General remarks Soft tissue management after maxillofacial osteotomies is important for the final esthetic result. Extensive additional soft tissue procedures are problematical because edema after the osteotomy makes proper judgment during handling of the soft tissues impossible. In addition, during extensive procedures on the nose, the nasal tube has to be changed in an oral intubation, compromising nasal surgery considerably. We therefore think that nose surgery is not possible simultaneously with a Le Fort I osteotomy. It is, however, possible with sagittal splitting procedures or genioplasties. Soft tissue procedures on the nose, which can be performed simultaneously with a Le Fort I osteotomy, are the alar cinch suture, resection of the anterior nasal spine, wedge excision of the alar base, grinding of the paranasal area, 8 and thinning of the columella. ln this sample of patients, only a V-Y plasty was performed in order to find out for which kind of maxillary movement a V-Y plasty suffices in creating a pleasing 36

37 Nasolabial esthetics after Le Fort I osteotomy and V-Y result. Therefore, 4 different groups were composed of patients who had only a Le Fort I osteotomy performed and had similar vectors of movement. Due to proper selection of the subgroups, only small numbers of patients could finally be included. Because there was considerable variation between patients, only the equations with P values < 0.05 were used here. The Pearson s correlation coefficient r was not used for further selection of equations, although a higher coefficient indicated a stronger correlation. The r 2 shown in Table 2-3 illustrates to what extent the equation explains the dependent variable and also, therefore, describes the variation. An r 2 of 1 means that there is no variation and every dependent point can be predicted by the equation. An r 2 of 0 means maximal variation; in these cases, no equation can be formulated. The method of error as described in Table 2-2 was also used by Van Butsele et al, 13 who found a mean error of all points in the X direction as 0.43 mm and for the Y direction as 0.42 mm. These results are comparable with ours. We found the mean error for the X direction to be 0.38 mm and for the Y direction to be 0.46 mm. Although a different software and digitizer were used here, the magnitude of the error seems to be in the same range. We therefore think that the method is reliable and can at least be used to compare these results with the results found in the literature. Betts et al 4 used the standard error of the mean and found for linear measurements 0.67 ± 0.09 mm. Radney and Jacobs 14 also used the standard error of the mean by measuring every landmark 3 separate times. After calculating the average deviation of the mean for each landmark, they estimated the overall mean error as 0.24 mm. In that study, however, every measurement was done by hand, without a computer. In this study it seemed that for the different kind of maxillary movements, different independent variables were selected by the computer for the same soft tissue point for formulating equations. Hence we looked at the independent points of all 51 patients with the highest r 2 value in order to find out for which bony point the highest correlation could be found for each soft tissue point. Using forward multiple regression analysis, the computer chose the independent point with the strongest r 2 value (Table 2-1). Posterior nasal spine did not seem to play a role of importance. It was interesting to note that the greatest influences on the soft tissue points of the nose were all bony movements of A-point and I-point in a horizontal direction. The greatest influences on the vertical movements of the soft 37

38 Chapter 2 tissue points of the nose were all horizontal bony movements of A-point. Horizontal soft tissue movements of the upper lip were influenced by horizontal movements of I-point with r 2 values of 0.52 and 0.58 (Table 2-2,first and third rows).the vertical movements of the upper lip were mainly influenced by vertical bony movements of A-point. For horizontal movements of the lip, I-point seemed to have had the greatest influence, whereas for vertical movements, A-point had the greatest influence on the upper lip. Discussion of the several directions of movement Impaction. Three equations could be formulated which met the criteria devised. Two equations defined structures of the upper lip. The vertical movement of stomion superior was defined by A-point and posterior nasal spine in the equation Stsy = 1.33Ay 1.49PNSy Two independent points defining for stomion superior were also found by Van Butsele et al 13 ; however, this pertained to their study for I-point and A-point and not for the posterior nasal spine. In our study, posterior nasal spine had a negative correlation coefficient, therefore dorsal impaction might have produced lip shortening. As the r 2 was 0.66, this equation might have indicated a strong relation between A-point and posterior nasal spine, on the one hand, and stomion superior on the other. In the literature, different ratio coefficients for stomion superior were found. Mansour et al 15 found a statistically significant ratio coefficient of 0.54 between stomion superior and the vertical movement of A-point. Rosen 6 found a ratio of 0.32 between I-point and stomion superior and an r 2 of Radney end Jacobs 14 found a statistically significant ratio of The r 2 value was They also found that the vertical reduction of the distance between labrale superior and stomion was contingent upon the vertical movement of the posterior nasal spine with ratio coefficient 0.39 and A-point with ratio coefficient This will result in vertical reduction of the upper lip in impaction cases. This effect of maxillary impaction was statistically ascertained here, although it was seen clinically in many patients. Probably the variation was such that formulating regression equations appeared impossible. As Schendel and Williamson 9 have pointed out, there is much variation between the 38

39 Nasolabial esthetics after Le Fort I osteotomy and V-Y independent and dependent points. A way to describe the relation between bony and soft tissue points more precisely would be to include more than 1 bony point in the equation. The r 2 would then probably have a greater value, as was the case in most of our com bined equations (Table 2-3). Horizontal movements of stomion were defined by the equation Stsx = 0.80Ix Despite a forward movement of 0.2 mm and a standard deviation of 1.1, this statistically significant equation could be formulated. The ratio coefficient was much higher than what other authors found. Stella et al 16 could not find a ratio between the amount of forward movement of the maxilla and the forward movement of stomion superior. Van Butsele et al 13 found that stomion superior moved upward 30% of the horizontal movement of I-point.The same ratio was found by Dann et al, 17 who found a ratio coefficient of 0.55 between I-point and labrale superior. Despite the high ratio coefficient of 0.80 found in this impaction group, it was evident that the upper lip would become thinner. The ratio coefficient was much higher compared to the results found in the literature, probably because of the very small forward movement of I-point. As the ratio coefficient for horizontal movements was 0.80, some lip shortening as described earlier along with thinning of the lip was predicted to be likely. A V-Y plasty seemed insufficient; therefore, forward movement of the soft tissues of the lip with a cinch suture in combination with a V-Y plasty as described by Schendel and Williamson 9 proved to be a better option in these cases. As there were no statistically significant effects on the nose, any conclusion concerning reduction of the anterior nasal spine cannot be made here. Advancement. Movements of the maxilla in different directions resulted in different equations with different bony points as independent variables. There were, however, some visible trends. Most statistically significant changes in a vertical or horizontal direction of the soft tissues of the nose were caused by horizontal movements of A-point and I-point. The equations for vertical soft tissue changes of the nose in advancement cases had negative ratio coefficients with horizontal movements of I-point (Table 2-3). This meant an increase of tip projection in advancement cases. The cinch suture prevented widening of the nose, but also increased tip projection. 7 With respect to the tip of the nose, a cinch suture would not be advantageous. For the increase of the 39