Treatment of Class II deep bite by orthodontic and surgical means

American

Journal

Founded in 1915

of ORTHODONTICS Volume 85 Copyright

Number I

January, 1984

0 1984 by The C. V. Mosby Cornpun?

ORIGINAL

ARTICLES

Treatment oj’class II deep bite by orthodontic and surgical means William H. Bell, D.D.S.,* Joe D. Jacobs, D.D.S.,** and Harry L. Legan, D.D.S.*** Dullus,

Texus

Conventional orthodontic correction of the Class II deep-bite deformity with a decreased lower anterior facial height tendency can be mechanically difficult, inefficient and, in many instances, impossible. Orthodontic treatment alone of either adults or adolescents with such deformities frequently can neither increase lower anterior facial height sufficiently to achieve ideal facial proportions nor achieve long-term occlusal stability. Despite the need for surgical intervention to achieve satisfactory occlusal and esthetic results, many patients with such deformities are still being treated in clinical practice by traditional orthodontic procedures, with less than ideal esthetic and/or occlusal results. The challenge to achieve efficient and stable treatment of this deformity has been met by the use of various surgical techniques in combination with orthodontic treatment. This combined surgical-orthodontic approach can provide increased treatment efficiency, long-term stability, and optimal esthetic results. The proper sequencing and correct selection of orthodontic mechanotherapy are essential to ensure the desired results. This article purposes to detail basic problems involved in diagnosis and treatment planning for the combined surgical-orthodontic approach to patients exhibiting Class II deep bite and decreased lower facial height. Orthodontic and surgical treatment objectives are explained, and representative case reports are presented and discussed to illustrate this method of treatment. Extraction patterns, control of the transverse dimension, arch wire selection, auxiliary wires, elastics, and extraoral appliance use are described. Surgically, the dentofacial disharmony associated with this deformity may defy treatment by surgical advancement of the mandible only. Genioplasty, Le Fort I osteotomy, symphyseal osteotomy, anterior or total mandibular subapical osteotomy, body osteotomy, submental lipectomy, and rhinoplasty are adjunctive procedures that are described and may be used in concert with mandibular advancement surgery.

Key words: Surgical orthodontics, mandibular treatment efficiency, mandibular advancement

deficiency.

T

he adult skeletal Class II deep bite remains one of the most challenging and yet common types of malocclusion treated today. Despite the fact that these *Professor, Department of Surgery, Division of Oral Surgery, University of Texas Health Science Center at Dallas, Center for Correction of Dentofacial Deformities. **Assistant Professor and Director of Orthodontics, Department of Surgery. Division of Oral Surgery, University of Texas Health Science Center af Dallas, Center for Correction of Dentofacial Deformities. +** Visiting Associate Professor, Department of Orthodontics, Baylor College of Dentistry.

Class II deep bite, decreased lower facial height.

patients may manifest a constellation of dental, facial, and skeletal problems, many of them are still treated by traditional orthodontic procedures, with less than ideal esthetic and/or occlusal results. Recognition of the complex and variable dentalskeletal-facial featuresIP (Figs. 4, 7, and 10) manifest by the adult patient with a Class II deep bite is essential for comprehensive treatment planning. Full-face examination typically discloses that the patient has a broad, square face and an edentulous appearance. When the mandible is at rest with the lips in repose, or when the 1

2

Bell,

Legutt,

and

.luc~h.s

patient is speaking or smiling, the maxillary incisors are minimally exposed or totally hidden behind the upper lip. Examination of the lower third of the face in frontal view typically reveals thin and curled competent lips. Analysis of the lower third of the face in profile reveals that the nasolabial angle is essentially normal or obtuse, so that the lower face appears short. The lower lip is positioned behind the upper lip; the chin is either deficient or normally positioned but is made more apparent by a deep labiomental fold. Cephalometrically, the lower face is short relative to the upper face (N-ANSIANS-Me 0.8 and GSniSn-Me 1).5s 6 Supramentale (point B) is posteriorly positioned, supporting the belief that in the majority of cases the Class II skeletal relationship is a result of anteroposterior mandibular deficiency, not anteroposterior maxillary hyperplasia. Frequently the palatal, occlusal, and mandibular planes tend to parallel the horizontal plane (Fig. 7, E). Excessive overjet and overbite and a Class II relation are the principal features of the occlusion. The lower arch shows an exaggerated curve of Spee, anterior crowding, and constriction of the canines. The maxillary dental arch form is wider and more ovoid than the mandibular arch. The palatal vault is typically flat. Maxillary buccal crossbites are not uncommonly associated with interdental spacing. Significant arch length deficiencies are relatively rare. Transverse maxillary excess is often accentuated by additional buccal tipping of the maxillary posterior teeth and concurrent lingual tipping of the mandibular posterior teeth due to function. These patients also typically exhibit a reverse curvature of the maxillary occlusal plane (Fig. 7, I and J). In nongrowing persons the malocclusion is correctable by orthodontic therapy, such as cervical headgear, extraction of premolars, Class II elastics, and other extrusive mechanics. These treatment modalities usually correct the deep bite by extrusion of posterior teeth, intrusion of lower incisors, and clockwise rotation of the mandible. The Class II relationship is corrected by exertion of a posterior force on the maxillary teeth. With such treatment, however, the skeletal and soft-tissue relations are improved only minimally, if at all. Indeed, midfacial esthetics may be significantly compromised. On the positive side, extrusive mechanics increases the lower facial height and often reduces the depth of the labiomental sulcus. However, as the mandible rotates clockwise secondary to orthodontic eruption of teeth, the Class II skeletal relationship tends to worsen and the chin becomes more retrusive. Increasing lower facial height and decreasing the large overbite in pa-

tients with decreased lower facial height and deep bite not only has distinct therapeutic limitations but is fraught with the possibility of relapse.’ Orthodontic extrusion of posterior teeth in persons who manifest a skeletal type of deep bite associated with heavy, strong jaw muscles may be difficult and time consuming because the extrusive mechanics must work against large occlusal forces. In addition, extraction of premolar teeth to facilitate correction of a Class II malocclusion adds to the complexity of the treatment and increases treatment time as opposed to nonextraction therapy. Mandibular advancement to correct the Class II relationship and open the bite posteriorly may obviate the need for extractions, facilitate extrusion of posterior teeth postsurgically, and increase treatment efficiency. (Compare Case 3 with Case 4.) There are numerous inherent treatment limitations when surgical options are not considered. This article will describe various surgical-orthodontic treatment options and their benefits. The desire to treat these patients orthodontically in concert with surgical intervention is based on three main goals: (1) to increase the efficiency of orthodontic mechanics; (2) to improve the facial esthetics; and (3) to enhance long-term stability (Figs. 7 to IO). ORTHODONTIC

CONSIDERATIONS

Orthodontic goals for treatment of patients exhibiting deep bite, Class II skeletal malocclusions, and decreased facial height have been previously described.x, u Ultimately, treatment of these patients should be finished with maxillary and mandibular incisors over basal bone, Class I canine occlusion, and good dental relationships both statically and functionally, normal overjet and overbite, coordinated arches in the transverse dimension, arch length discrepancies alleviated, and level occlusal planes. A primary clinical question is which of these orthodontic objectives should be accomplished prior to surgery and which should be deferred to postoperative therapy to provide optimum stability, function, esthetics, and efficiency of treatment. Anteroposterior

dimension

Prior to surgical intervention, arch length discrepancies should be determined and alleviated, with or without extractions. The judgment concerning extractions should be based on anteroposterior incisor position, the amount of crowding exhibited, soft-tissue relationship, etc. Nonextraction therapy is preferred whenever possible. When extractions are necessary, however, maxillary second premolars and mandibular first premolars are most often removed. This particular

Treatment of Class II deep bite

Volume 85 1

3

Number

extraction therapy facilitates maximum anchorage mechanics in the mandibular arch to alleviate excessive crowding (usually more than in the maxillary arch) and maximally retract the mandibular incisors to a stable position over basal bone. It also minimizes anchorage in the maxillary arch, where arch deficiencies are usually less pronounced and nasolabial relationships are within acceptable limits. Also, minimal sagittal changes in the position of the maxillary incisors result. The usual situation of maximum anchorage in the mandibular arch and minimum to moderate anchorage in the maxillary arch lends itself to the use of Class III elastics in some cases. Certainly, if the patient requires moderate to maximal retraction of maxillary incisors to correct an acute nasolabial angle, then maxillary first premolar extractions are indicated. In most instances, properly executed preoperative orthodontic treatment will result in increased horizontal overjet (Fig. 8, Case 2). Transverse

dimension

The interarch transverse relationship that is exhibited in most cases may be described as relative maxillary excess. Clinically, the patient will exhibit a tendency toward bilateral buccal crossbite in centric relation. This discrepancy, however, is minimized when the mandible is postured into a Class I canine relationship. In such cases, therefore, routine arch coordination in anticipation of the mandibular advancement should be accomplished prior to surgical intervention. If, however, an absolute transverse maxillary excess is exhibited even after simulation of the sagittal correction, then a definitive surgical procedure to narrow the maxilla or widen the mandible may be indicated concurrent with the mandibular advancement. In such cases, the preoperative orthodontic treatment in the maxillary arch should be accomplished sectionaliy in anticipated surgical segments. Conversely, if an absolute transverse maxillary deficiency is exhibited in the simulated Class I interarch relationship, consideration should be given to (1) rapid palatal expansion following lateral maxillary osteotomies as part of the preoperative orthodontic therapy for arch coordination,“. ‘I (2) segmental maxillary surgery (following sectional orthodontic therapy) concomitantly with the mandibular advancement to achieve such coordination, or (3) narrowing of the mandible with a symphyseal split in conjunction with the advancement.‘z Vertical

dimension

To ensure the optimum in esthetic improvement, stability, and function following treatment, all of the aforementioned orthodontic objectives should be ac-

complished prior to the definitive surgical advancement of the mandible. Accomplishing these objectives may take a few weeks or several months, depending upon the particular case. Therefore, decisions concerning the sagittal and transverse dimensions are not major considerations relative to length of treatment. The vertical dimension, however, may offer the orthodontist an opportunity to maximize the efficiency with which he accomplishes the ultimate objectives of his therapy, perhaps reducing treatment time and minimizing the patient’s inconvenience and/or discomfort. The difficulty of leveling the mandibular arch in the adult patient who has a severely accentuated curve of Spee, a Class II malocclusion, a low mandibular plane angle, and insufficient lower anterior facial height is well known. Many months of reverse-curve arch and anterior bite plane therapy are commonly required in these cases. Therefore, it is only logical to postpone leveling of the mandibular arch in such cases until after surgical advancement of the mandible has been carried out. Such sequencing of treatment decreases ultimate treatment time for the patient by many months and eliminates the use of the anterior bite plane. The leveling of the mandibular arch is accomplished postoperatively with premolar/molar up-and-down elastic therapy in a relatively short period of time because of the lack of occlusal interferences and functional muscle pressures associated preoperatively with such cases. Advancement of the mandible prior to leveling of the mandibular accentuated curve of Spee will result, following fixation and splint removal. in an occlusion that is tripoded on the anterior teeth and second molars bilaterally. Typically, there will be a substantial open bite distal to the canines in the canine/premolar/molar region. Although the mandibular arch should be leveled postsurgically. the maxillary arch should be leveled prior to surgery, for several reasons. The maxillary arch typically is much easier to level, and doing so requires a minimal amount of treatment time. Also, proper torque of the maxillary incisors must be accomplished prior to surgery to ensure the attainment of a Class I sagittal canine relationship at the time of surgical mandibular advancement. If the maxillary arch is not level prior to surgery, the maxillary incisors will be too upright in most instances to facilitate a Class I canine relationship without the necessity of an anterior crossbite (or overcorrection), which is not advisable. It is also ideal for the maxillary arch to act as a stabilizing arch equipped with a rigid full-bracket-width rectangular stainless steel arch wire, against which a resilient mandibular arch wire and elastics may be pitted to facilitate mandibular arch leveling with little reciprocat-

4 Bell, Legan, und Jucobs

Am. J. Orthod. January 1984

Fig. 1. Treatment of Class II deep-bite deformity by orthodontic means (nonextraction), mandibular advancement, and advancement genioplasty. A, Presurgical orthodontic treatment of Class II, Division 2 deep-bite malocclusion with reverse curve in maxillary arch and excessive mandibular curve of Spee. Small arrows indicate planned positional movements of maxillary teeth to level and align maxillary arch. Solid lines indicate planned sagittal split ramus osteotomies and advancement genioplasty. Larger arrows indicate planned positional movements of mandible by sagittal split ramus osteotomies and of chin by advancement genioplasty. B, After mandibular advancement, the residual curve in the mandibular arch is leveled primarily by extrusion of the mandibular premolar and first molar teeth. C, Mandible and chin fixed in planned relationship after mandibular advancement and advancement genioplasty. Mandibular arch leveled; Class I canine and molar relationships have been achieved.

ing movement of the maxillary dentition. In most cases the mandibular surgical wire will act also as the leveling arch after fixation and splint removal. Therefore, a light round stainless steel wire or a large but resilient rectangular wire, such as TMA or nitinol, should be placed immediately prior to surgery (Fig. 1, Fig. 7, and Fig. 9). Following surgery, the patient should wear continuous light elastics in a triangular or box formation with a slight Class III vector in the premolar/molar region. It has been observed clinically that, with the rapid leveling of the mandibular arch via such elastic therapy, the mandible itself remains stable and the mandibular incisors do not flare significantly (Fig. 7, F, bottom). Given excellent surgical technique and attainment of the proper overjet-overbite relationship at the time of surgery, the arch length required to facilitate leveling appears to be obtained mostly through distal crown movement of the mandibular posterior teeth (Fig. 7, F, bottom). Such distal movement is ideal, for in most cases a slight Class III molar relationship will exist upon removal of fixation when the incisal and canine relationships are ideal, the maxillary arch is

level, and an accentuated mandibular curve of Spee still exists. SURGICAL

OPTIONS

Careful attention to the many details of esthetic, functional, and cephalometric planning studies will usually evolve a plan of treatment that will allow simultaneous correction of both the occlusal and esthetic disharmony associated with the Class II deep-bite deformity. The clinical manifestations in such patients frequently defy treatment by surgical advancement of the mandible only. Genioplasty , Le Fort I osteotomy, symphyseal osteotomy, anterior mandibular subapical osteotomy, body osteotomy, total mandibular subapical osteotomy. submental lipectomy, and rhinoplasty are the surgical procedures that may be used most frequently in concert with mandibular advancement surgery to achieve anteroposterior, vertical, and transverse facial proportionality. Anteroposterior

dimension

The common denominator of successful treatment of absolute mandibular deficiency involves surgical ad-

Treutment of Class II deep bite

Volume 85 Number 1

Fig. 2. Mandibular advancement by extraoral inverted ‘I” osteotomies and interpositional to increase vertical ramus height and length and by advancement genioplasty. Planned are illustrated by bold lines; arrows indicate directional movements.

vancement of the mandible into a stable relationship with the maxilla (Fig. 1). With careful treatment planning,“. x. !‘. “j meticulous execution of surgical techniques ,!’ good preoperative and postoperative care ,“’ and coordination of surgery with efficient postsurgical orthodontic therapy and rehabilitation,‘” the mandible can be advanced surgically with relatively few adverse sequelae and complications. Suprahyoid myotomies, the use of cervical collars, and opening of the bite in the posterior region to compensate for relapse are not required. Limited accessibility of the oral cavity, restricted jaw opening, and excessively small mandibular rami may be indications for extraoral ramus surgery. The extraoral inverted “L” osteotomy is a dependable procedure for treating severe mandibular hypoplasia, typically manifest in patients with juvenile rheumatoid arthritis, mandibular ankylosis, and certain syndromes (Fig. 2). Such persons frequently manifest mandibular deficiency in the vertical and anteroposterior planes of space in addition to posterior vertical maxillary deficienc y Vertical

dimension

Although the mandibular deficiency deep-bite deformity generally involves the anteroposterior dimension, the vertical and transverse dimensions are also frequently abnormal. Vertical abnormalities may be manifest in the mandible or maxilla. Decreased lower anterior facial height may be corrected by Le Fort I

5

bone grafts osteotomies

osteotomy and interpositional bone grafting, genioplasty with interpositional bone grafting, or total mandibular subapical osteotomy and interpositional bone grafting. These procedures are all designed to increase facial height and/or the amount of tooth exposure. Correction of the deep bite by mandibular advancement to achieve a satisfactory overbite and overjet relationship also increases the lower anterior facial height.“. K-‘~ Class 11mandibular-deficiency deep bite with vertical maxillary deficiency requires analysis and correction in all three planes of space. Multiple surgical procedures involving the maxilla, mandible, and chin are usually performed during a single operation. There may be a vertical abnormality consisting of deep bite, decreased lower anterior facial height, vertical maxillary deficiency manifest as a lack of tooth exposure in repose and a relative lack of tooth exposure when the patient is smiling, and lack of chin and mandibular body height .” The hallmarks of vertical maxillary deficiency are decreased maxillary height and a relative or complete lack of tooth exposure when the patient is smiling. The relationship of the upper lip to the incisors with the lips relaxed and the teeth disoccluded is the keystone for planning treatment that will achieve an attractive smile. “’ The anatomy of the person’s smile, the length of the incisor clinical crowns, the lip-to-nose relationship, the angulation of the maxillary incisors, and the height of the upper lip in relation to the gingival margin of the upper incisors are additional important parame-

6 Bell, Legarz, und Jucoh.~

Am. J. Orhod. Junwry 1984

Fig. 3. A and B, Correction of Class II malocclusion by Le Fort I osteotomy and interpositional bone graft to reposition the maxilla inferiorly and slightly posteriorly to improve the smile line, reduce the upper lip prominence, and correct the Class II malocclusion. As the maxilla was repositioned inferiorly, the mandible rotated clockwise inferiorly and posteriorly to correct the anterior crossbite and reduce the chin prominence. Reduction of chin prominence was treated by advancement genioplasty.

Fig. 4. Surgical techniques for correction of Class II deep-bite malocclusion associated with vertical maxillary deficiency, decreased chin height, and absolute mandibular deficiency. A, Surgical plan: Le Fort I osteotomy to increase vertical dimension of maxilla, sagittal split ramus osteotomies to advance mandible, and interpositional genioplasty to increase chin height. B, Postoperative result; Increased facial height and Class I occlusion; interpositional bone grafts in place; maxilla stabilized by suspension wires and metallic bone plates.

ters which may support the need for Le Fort I osteotomy in concert with interpositional bone grafting to increase maxillary height and the amount of tooth exposure. The objective of such treatment is to increase maxillary height and the amount of tooth exposure so as

to produce an attractive smile in which the upper lip is near or a little below the height of the gingival margin of the maxillary incisors. The upper lip curvature is most esthetic when the corners of the mouth are above the midline of the upper lip. The maxilla is repositioned

Volume 85 Number 1

Trecttment of Cluss II deep bite

Fig. 4 (Cont’d). C to F, Facial appearance of 19-year-old before (C and D) and after (E and F) surgical procedures

inferiorly the amount necessary to achieve 2 to 4 mm of maxillary incisor exposure with the upper lip at rest. If the upper lip is relatively prominent and the nasolabial angle is acute, the maxilla is repositioned inferiorly and posteriorly to reduce the upper lip prominence (Fig. 3). Inferior repositioning of the maxilla rotates the mandible downward and backward, reduces the prominence of the chin, and increases the lower anterior facial height. If cephalometric planning studies indicate that the upper lip will become too retrusive with the planned backward and inferior movement of the maxilla, the maxilla is repositioned directly inferior or anterior and inferior; this repositioning is predicated on simultaneous mandibular advancement surgery to achieve a Class I canine occlusion (Fig. 4).

male patient with Class II deep-bite illustrated in A and B.

7

deformity

The reverse curve in the maxillary arch is usually amenable to leveling by efficient orthodontic mechanics. In selected patients, however, excessive residual curvature may be corrected by transverse segmentalization of the maxilla in an appropriate interdental space. Vertical and transverse maxillary dysplasias are corrected concomitantly. When there is clinically significant vertical maxillary excess associated with Class II deep-bite deformities, correction may be accomplished by superior and posterior repositioning of the maxilla to achieve a Class I occlusion. Esthetic consideration will, of course, determine whether or not other mandibular advancement or chin surgical procedures are indicated. Extreme

c‘nre and discretion

must he used in planning

Fig. 5. Surgical

technique for correction of Class II deep-bite malocclusion by total subapical osteotomy of the mandible and interpositional autogenous bone graft. A, Typical dental, skeletal, and facial features of Class II deep-bite deformity with mandible in centric relation. Solid lines indicate planned sagittal, interdental, and subapical bone incisions; arrows indicate directronal movement of dentoalveolar segments. 6, Deep bite leveled, lower anterior facial height increased, and labiomental fold decreased by total subapical osteotomy and concomitant autogenous interpositional bone graft. C and D, Facial appearance of 18year-old boy before and after correction of Class II deep bite by total subapical osteotomy of the mandible. After surgery, facial height remains disproportionate and there is an unesthetic submental-cervtcal area. E and F, Occlusion before and 4 years after surgery. Although occlusal stability has been maintained after surgery, patients with similar deformities are today routinely treated by surgical techniques illustrated in Fig. 4 and concomitant submental lipectomy. (Orthodontic treatment by Dan C. Peavy, San Antonio, Texas.)

the amount oj’ superior repositioning oj’ the muillu so us to ur\wid e.wessivc shortening of the jtice cd concwrlment of’ marillut? inr~isor teeth. Superior movements of only 3 or 4 mm are occasionally indicated to reduce the amount of tooth and gingiva exposure. The type of mandibular surgery chosen will depend on the amount of overjet, the anteroposterior position of pogonion, and the lower anterior facial height. When there is a deep labiomental fold associated with adequate chin prominence, the entire dentoalveolar portion of the mandible may be advanced by means of a total

sagittal-subapical osteotomy of the mandible. In addition, a bone graft may be placed between the dentoalveolar and inferior portions of the mandible to achieve an increase in the lower anterior facial height (Fig. 5). I’ More frequently. however, the mandible is advanced and the chin prominence is simultaneously reduced by reduction genioplasty. and submental fat is removed by submental lipectomy (Fig. 6).‘. I7 I!’ Horizontal osteotomy of the inferior border of the mandible and concomitant interpositional genioplasty provide a very predictable means of increasing the lower anterior fa-

Fig. 6. A and 6, Facial appearance vancement, reduction genioplasty,

of 24-year-old and submental

cial height still further when mandibular chin height is disproportionately small (Fig. 4). Great versatility is likewise possible with this genioplasty technique to increase or decrease the chin prominence or width.“’ Subapical osteotomy may be used to partially level the mandibular occlusal plane and/or increase the arch length when extractions are contraindicated. Occasionally subapical osteotomy is a substitute for orthodontic leveling of the mandibular arch when significant intrusion of mandibular incisors is necessary in patients who manifest normal or excessive lower anterior facial height. This surgical procedure can be performed either at the same time as surgical advancement of the mandible or independently. When there is minimal to moderate crowding in the lower anterior arch, the segment may be advanced to increase the arch length as much as 6 mm (3 mm on either side).” The increased arch length will facilitate postsurgical orthodontic treatment of the crowded and malaligned incisors without premolar or incisor extraction.“’ This procedure is most frequently done independently of mandibular advancement surgery, with the aid of local anesthesia or general anesthesia, in the canine-premolar or canine-lateral incisor interspaces. In addition, the technique permits simultaneous leveling of the mandibular arch and improvement of the

woman lipectomy.

before

and

4 years

after

mandibular

ad-

relationship of the incisors to their supporting bone.” When intrusion of the mandibular anterior teeth is indicated in a person with decreased lower anterior facial height, mandibular body osteotomies may be performed in lieu of anterior subapical osteotomies to simultaneously level the mandibular occlusal plane and proportionally increase the lower anterior facial height. In terms of altering the mandibular anterior tooth-tobone relationship, there is considerably less versatility with the body osteotomy than with the subapical osteotomy The submental-cervical region is frequently unesthetic in patients with Class 11deep bite who manifest a retropositioned mandible, an abnormally large submental fat pad, an inferiorly positioned hyoid bone, and decreased lower anterior facial height. Because restoration of a normal chin-neck contour is essential for optimal facial esthetics, advancement or interpositional genioplasty, submental lipectomy, and mandibular advancement may all have a very positive effect on the submental-cervical esthetics. When submental liposis is present, it can be removed easily through a submental incision at the time of mandibular advancement and genioplasty (Fig. 6). If, however, the chin-neck contour deformity is caused by aging cutaneous tissues, face-lifting surgical procedures are indicated.

10

Bell, Legan, and Jacobs

Fig. 7. Case 1. A and 6, Facial appearance of 25-year-old man before treatment. C and D, Facial appearance after treatment. E, Cephalometric tracing before treatment (at age 25). F, Top. Composite cephalometric tracings before treatment and before surgery showing positional changes of teeth achieved by presurgical orthodontics. Bottom, Composite cephalometric tracings (superimposed on mandibular symphysis) immediately after mandibular advancement and at the end of orthodontic treatment. After mandibular advancement, the mandibular arch was leveled by continuous elastic therapy. The mandible remained stable, and the mandibular incisors did not flare. The arch length required to facilitate leveling was obtained primarily through distal crown movement of the mandibular molar teeth.

Am. J. Orthod. January 1984

Volume 85 Number I

Fig. 7 (Cont’d).

G, Composite cephalometric tracings showing Division 2 deep-bite malocclusion

CASE CASE

cephalometric tracings before and after treatment. skeletal stability during postoperative follow-up period. before treatment.

REPORTS 1

A 25-year-old man was referred for treatment of a Class II. Division 2. deep-bite malocclusion (Fig. 7). The patient exhibited a symmetrical square face with good balance in the upper and middle thirds. He displayed a symmetrical smile with adequate tooth exposure. In profile, the nasolabial angle was slightly obtuse and the lower lip was everted. The upper lip and the lower third of the face were in satisfactory proportion. The patient’s retropositioned mandible and deep labiomental fold were his dominant esthetic problems (Fig. 7. A and B). skeletal Cephalometric analysis revealed an absolute mandibular deficiency with deep bite, parallel facial planes. and the mandible rotated closed (Go-GnlS-N = 20”) (Fig. 7.

H, Composite I and J, Class II,

E). The maxillary incisors were upright and inclined lingually. The mandibular incisors were positioned normally over their supporting bone. There was an excessive curve of Spee. The patient had a full-cusp Class II. Division 2 malocclusion with an 8 mm overjet and a 12 mm overbite (Fig. 7. I and J). With the mandible positioned into a simulated Class I occlusal relationship. there was a horizontal maxillary deficiency. 3 mm in the canine and 4 mm in the molar regions. The overerupted lower incisors were biting into the palatal tissue. There was a severe reverse curve in the maxillary arch and an excessive curve of Spee in the mandibular ar-ch. The maxillary and mandibular arches were square and symmetrical. There was mild crowding in the anterior maxilla and mandible; the posterior teeth were well aligned. with Presurgical orthodontic treatment was achieved

12

Bell, Legan, and Jacobs

Flg. 7 (Cont’d). lar arch has

Am. J. Orthod. JanuaT 1984

K, Occlusion

after

presurgical

orthodontics.

Maxillary

arch has been

leveled;

mandibu-

been partially leveled. L and M, Occlusion after treatment.

0.022 X 0.025 inch edgewise brackets. Complete leveling and alignment of the maxillary arch, without extractions, were accomplished by extruding the premolars and first molars and proclining the maxillary incisors. The mandibular arch was aligned and partially leveled without extractions. After these objectives were accomplished within 9 months, there was a 9 mm overjet and the maxillary and mandibular incisors were in good relationship to their respective bony bases (Fig. 7, F top and K). At this point in the treatment process, the mandible was advanced surgically into the planned relationship by bilateral sagittal split ramus osteotomies. An interdental osteotomy was made in the mandibular left canine-lateral incisor interspace to facilitate narrowing in the intercanine and intermolar areas. This surgery was designed to compensate for the horizontal deficiency in the maxillary arch. Intermaxillary fixation was removed 7 weeks later. Final leveling, alignment, and detailing of the occlusion were accomplished in another 4 months. With the use of 0.021 X 0.025 inch rectangular nitinol arch wire, the open bite in the premolarfirst molar region was closed within 2 months by continuous vertical elastic traction in the premolar region (Fig. 7, L and M). The mandible remained stable, and the mandibular incisors did not flare. The arch length required to facilitate leveling was obtained primarily through distal crown movement of the mandibular molar teeth (Fig. 7, F bottom). A total of 15 months of active orthodontic treatment was required to achieve the final occlusal result (Fig. 7, L and M). An upper Hawley type of removable retainer was worn full

time for 6 months postoperatively. A fixed retainer was worn throughout Occlusal and skeletal stability have a 30-month postoperative follow-up and M). CASE

lower canine-to-canine the retention period. been maintained over period (Fig. 7, H. L.

2

A 3 1 -year-old woman was seen initially for treatment of a dentofacial deformity. All study parameters showed the facial esthetics commonly associated with an absolute mandibular deficiency. The patient habitually postured her mandible forward to compensate for the Class II malocclusion. The patient exhibited a slightly reduced amount of tooth structure during smiling and facial animation and in repose. In profile, she manifested a moderately acute nasolabial angle, a prominent upper lip. an everted lower lip, and a retropositioned mandible. There was a proportionate relationship between the chin. the nose. and the lips with the mandible postured forward into a simulated Class I occlusion (Fig. 8, A and B). Cephalometric analysis revealed that the maxillary and mandibular incisors were excessively flared (Fig. 8, E). There was an absolute mandibular deficiency; the chin was positioned 15 mm posterior to the subnasale vertical reference line. Occlusal analysis showed that the maxilla and mandible were tapered and symmetrical. The maxillary incisors were slightly crowded and inclined labially. The mandibular incisors were moderately crowded and also inclined labially.

Treatment of Class II deep bite

Volume 85 Number I

13

Fig. 8. Case 2. A and B, Facial appearance of 31-year-old woman before treatment. C and D, Facial appearance after treatment. E, Cephalometric tracing before treatment. F, Composite cephalometric tracings before and after treatment

The patient had a Class II. Division I malocclusion with a 13 mm overjet; the lower incisors were biting into the palatal mucosa (Fig. 8. H and I). Four first premolars were extracted to facilitate leveling and alignment of the teeth and moderate retraction of both maxillary and mandibular incisors. Presurpical orthodontic treatment involved partial leveling and alignment of the maxillary arch. partial leveling and alignment of the mandibular arch, coordination of maxillary and mandibular arches. and complete closure of all extraction spaces. These objectives were accomplished in a period of 8 months. The mandible was advanced 12 mm into an end-to-end anterior occlusion and Class I molar relationship by means of bilateral sapittal split ramus osteotomies. After release of intermaxillary fixation 8 weeks after surgery, light nighttime training elastics were worn in combination with a functional wafer splint for another 2 weeks. Vertical elastic traction with a Class II vector of force applied to the incompletely leveled maxillary arch caused an asymmetrical functional shift of the

mandible to the right. The short-term use of vertical elastics rapidly compensated for this shift. Continuous vertical elastic traction and arch wire therapy completed leveling of the mandibular arch by extrusion of premolars within another 2 months. Final interdigitation and detailing of the occlusion were achieved within 4 months after surgery with the use of a positioner and occlusal equilibration. Occlusal and skeletal stability have been maintained over a 3-year postoperative follow-up period. A total of 16 months of active orthodontic treatment was required. This treatment time was reduced sipnificantly by partial leveling of the mandibular arch after surgical advancement of the mandible (Fig. 8. J and K). CASE 3 A 24-year-old man was referred for treatment of a severe malocclusion and a retrusive mandible. Clinical examination disclosed facial symmetry with good balance in the upper and middle thirds. The patient’s symmetrical, esthetic smile revealed normal exposure of gingiva. The upper and middle

Atn J. Orrhod. .Jmuur~ 1984

Fig. 8 (Cont’d). G, Composite cephalometric tracings demonstrating skeletal stability during postoperative follow-up period. H and I, Class II, Division 1 deep-bite malocclusion before treatment. J and K, Occlusion after treatment. facial thirds were in good proportion. with 3 mm of upper incisor exposure in repose. The nasolabial angle was slightly obtuse; the lower lip was rolled beneath the maxillary and mandibular incisal edges and everted. The patient’s retropositioned chin and mandible contributed to the convex profile and unesthetic submental-cervical region (Fig. 9, A and B). Cephalometric analysis revealed a convex facial profile (angle of facial convexity = 28”) due primarily to an absolute mandibular deficiency (GV-Sn = ~ I3 mm).” There was also a nearly normal anteroposterior projection of the maxilla. The vertical facial proportion (G-SniSn-Me’) was nearly normal. as was the position of the maxillary and mandibular anterior teeth relative to their supporting bone (Fip. 9. E). The arch forms did not correspond. in that the buccal segments of the lower arch diverged more than those of the maxillary arch. This produced a posterior crossbite when the

teeth were occluded in a Class I relation (absolute transverse maxillary deficiency. 3 mm in the canine and 4 mm in the molar regions), An exaggerated curve of Spee was present in the mandibular arch, and there was a moderate reverse curve in the maxillary arch. A Class 11. Division I malocclusion with an 8 mm overjet and a 9 mm overbite was present; the lower incisors contacted the palatal mucosa (Fig. 9. I and./). There was minimal crowding and malalignment of the mandibular teeth. Spaces were present between the maxillary incisors, which were slightly inclined to the labial. There was an ankylosed mandibular left deciduous second molar. and the lower left second premolar was missing. The deciduous molar was extracted. and the arches were then banded/bonded with a “xepmented arch” edgewise appliance. Since the patient’s vertical facial proportions were within normal limits and since he desired rapid completion of

Treutment

Volume 85 Number 1

Fig. 9. Case 3. A and B, Facial appearance after treatment.

appearance

of 24-year-old

treatment. early surgical intervention was proposed. The leveling would be accomplished much more efficiently by extrusion of posterior teeth after surgical treatment since a posterior open bite would be created and there would be no occlusal forces hindering eruption of the teeth. Surgical alleviation of the transverse discrepancy was planned. Minimal alignment and leveling with rapid progression to a rectangular arch wire of sufficient dimension were the prime objectives of the presurgical orthodontic phase of treatment. Bilateral sagittal split osteotomies of the vertical rami were performed to reposition the mandible downward and forward into a Class I canine-and-molar relationship. A genioplasty was performed concomitantly to advance the chin 8 mm in order to increase the chin prominence and improve the submental-cervical esthetics. An interdental osteotomy was made in the mandibular left central incisor-lateral incisor interspace to facilitate narrowing in the intercanine and inter-

man

before

treatment.

of Class

C and

II deep

bite

15

:acial

molar areas. This surgery was designed to compensate for horizontal deficiency in the maxillary arch. The postoperative occlusion, which was associated with an open bite in the premolar-first molar region, was stabilized with an interocclusal wafer splint and maxillomandibular ligatures fixed to orthodontic stabilizing arch wires. After 8 weeks of maxillomandibular fixation, the interocclusal splint was removed and ligated to the lower arch wire. For 2 subsequent weeks it was used as a functional splint to maintain the planned anteroposterior relationship. Nighttime vertical elastics were worn simultaneously in the canine regions. Two weeks after release from maxillomandibular fixation, there was no discernible clinical or cephalometric evidence of relapse. Upon removal of the occlusal splint (approximately 10 weeks after surgery), active orthodontic mechanics were resumed to readily close the posterior open bite (Fig. 9, K).

76

Bell, Legan, and Jacobs

Am. J. Orrhod. January 1984

M.H.

24-l I ____ 25-f /fi

M. H.

- 24-7 ---- 26-l e-

Fig. 9 (Cont’d). E, Cephalometric tracings before and after surgery. Composite cephalometric tracings

tracing before treatment (age 24 years). F, Composite cephalometric G, Composite cephalometric tracings before and after treatment. showing skeletal stability during postoperative follow-up period.

Initially, a light 0.016 inch lower arch wire was inserted. maintaining the 0.018 by 0.025 inch rectangular maxillary arch wire in place. In addition. a high-pull headgear with the outer bow anterior to the maxillary center of resistance and activated to 450 gm was worn 14 hours per day. This allowed for more eruption of mandibular posterior teeth than of maxillary teeth, as was needed. Also, a mandibular intrusive base arch was inserted at this time. When activated to heavierthan-normal forces, the base arch is an efficient means of extruding posterior teeth while maintaining sufficient intrusive force on the anterior teeth to obviate deepening of the overbite. Light Class II trapezoidal elastics were used at night. The patient was seen by his orthodontist at 2-week intervals, and within 3 months the teeth were intercuspating well.

H,

Bands were then removed, and the patient was instructed to wear a positioner 4 hours per day and all night. After 3 months of positioner wear. an upper Hawley retainer and a lower spring retainer were placed. To reiterate, the mandible was advanced surgically 8 mm and maintained in its new position during the postsurgical orthodontic treatment phase (Fig. 9, F and G). At debanding, approximately 8 months after the commencement of therapy, the patient was deemed to have an excellent functional and esthetic treatment result (Fig. 9. C and D, G, L, and M). When assessed both statically and functionally, the occlusion was considered to be very good. The anteroposterior mandibular position and Class 1 occlusion have remained quite stable over a 45-month period (Fig. 9, H, L, and M).

Fig. 9 (Cont’d). surgery

CASE

4 A 30.year-old

II.

Division The

man

tooth

smiling.

In profile. patient’s

fold.

and relatively

mandibular

patient and

short

lower

angle

and mandibular

anterior

deep

deep

the were

and

the labial

and associated

and

dible

was

obtuse.

labiomental

height

were

parallel = 18”). 10. E). II.

square

facial

lary

and

his

planes. proclined

Division

overbite

palatal

There

(IO

mucosa.

I malocmm). The

and symmetrical.

The

treatment

by Dr

Harry

C. K&r.

Dallas.

Texas.

markedly

regions

a simulated

Class

reverse

curve

of

deficiency when

the

man-

I occlusal

curve Spee

to

in the anterior

maxillary

molar

a severe

inclined

spacing

Horirontal and

an excessive

with maxilThe

objective

to

align.

without sure

were

ing

the

of

deep

in Food

overbite

would

in

in the

rela-

the

maxil-

mandibular

x 0.025

increase

the

of

the

mandibular inch

The

edpewise

while to

mandible. by

mandibular were

multiple

expofirst

maintaining

the

arch

of incisor and facilitate

primarily

arches

treatment maxillary

mandibular

crowding

Spee

be corrected

in the amount

incisors.

relationship

of

orthodontic

spaces

to relieve

curve

extraction and

presur$cal close

of upper

extracted

incisors cisors. Aifcr-

the and

and

by extrusion

molars

0.01X

of

level.

extractions

maxillary *Orthodonttc

was

were

moderate

.I).

into

after

arch

skeletal

and

IO. I and

positioned

arch

incisors with

in the canine

tionship.

was

absolute

mandibular

(Fig.

manifest

during

sliphtly

deep

an

Class

anterior

contactinp arches

was facial

bite.

a full

maxillary

was

smile and

before treatment. K, Occlusion M, Occlusion after treatment

pro-

10. A and B).

(Go-Gn/S-N teeth (Fif.

manifested

vertically

in repose

revjealed

with

a severely

lips

(Fig.

analysis

incisors

of a Class

maxilla and

mandible.

problems

deficiency

the lower

the

naaolabial

rotated closed and mandibular

The clusion

with

the

Cephalometric

treatment

as a symmetrical

retropositioned

esthetic

mandible maxillary

as well

exposure

The

for

a symmetrical

face.

adequate

referred

malocclusion.~~

exhibited

square

dominant

was

I deep-bite patient

portionate

lary

I and J, Class II, Division 1 deep-bite malocclusion of release from maxillomandibular fixation. L and

at time

the The

depression

first fully brackets.

premolars. banded The

prelevellower

10 mm of

inthe with

arches

18

Am. J. Orthod. January 1984

Bell, Legan, and Jacobs

Fig. 10. ( Zase 4. A and B, Facial appearance after treatment

appearance

of 30-year-old

were leveled and aligned with this appliance. The objective in the upper arch was to extrude the premolar teeth, close the anterior interdental spaces, and upright the incisors. This was accomplished by means of light arch wires with vertical loops and elastic forces from molar to molar. Similar mechanics were used in the lower arch after extraction of first premolars. Heavy vertical posterior elastics were used to aid in bite opening. After the lower arch was fairly well leveled. the lower spaces were closed. Following lower-space closure. various arch wires with reverse curves were used to complete leveling in the lower arch. After the overbite had been almost completely opened orthodontically. there was a minimal amount of overbite. a 12 mm overjet. and a good relationship of the upper and lower incisors to their respective bony bases (Fig. 10, F andK). The desired occlusal relationship was maintained by observing the

man

before

treatment.

C and

D, Fa cial

occlusal relationship when the patient postured his mandible forward. Progress models were also used for the same purpose and for construction of an interocclusal splint. At this point in the treatment process, the mandible was advanced 12 mm into a Class I canine and Class III molar relationship be means of bilateral sagittal split osteotomies of the vertical rami (Fig. 10, G). A vertical osteotomy was performed in the mandibular right lateral incisor-canine interdental space to facilitate leveling of the arch, closure of residual space, and narrowing of the lower arch. Intermaxillary fixation was removed 7 weeks postoperatively. Final leveling. alignment, and detailing of the occlusion were accomplished in another 4 months (Fig. 10, L and M). The Class II. Division 1 deep bite was corrected by surgical and orthodontic procedures to achieve a balanced softtissue profile and functional occlusion (Fig. 10. C. L. and&f).

Twrrtmnt

----

cf Cl~tss

M.D. 30-2 33-3 P.-f-

Fig. 10 (Cont’d). E, Cephalometric tracing before treatment. F, Composite cephaiometric tracings before treatment and before surgery showing positional changes of teeth achieved by presurgical orthodontics. G, Composite cephalometric tracings showing skeletal stability over 40-month postoperative follow-up period.

Fig. 10 (Cont’d). after presurgical after treatment.

I and J, Class II, Division 1 deep-bite orthodontics; maxillary and mandibular

malocclusion arches have

before treatment. been leveled. Land

K, Occlusion M, Occlusion

II deep

bite

19

20

Bell,

Legan,

Am. .I. Orthod. Jnnua~ 1984

and Jacobs

The upper molar position remained constant, and upper incisors were in good relationship to the maxilla. The lower teeth were also well related to the mandible. The deep anterior bite was corrected primarily by depressing the lower anterior teeth. There was relatively little vertical change in the posterior molars. After the mandible was surgically advanced 12 mm. the overbite and overjet were fully corrected (Fig. 10, F, G, L, andM). An upper Hawley type of removable retainer was worn full time for 24 months postoperatively. A lower canineto-canine fixed retainer was worn throughout the retention period. Despite the long-term orthodontic treatment, no significant root resorption was discernible during or after treatment. The postoperative progress of this patient has been followed for 3% years. Despite the long period of presurgical orthodontic therapy (30 months). he continues to exhibit excellent skeletal and dental stability (Fig. 10. H. L, and M).

In selected adult patients who manifest relatively normal or long lower anterior facial height, most of the leveling can be accomplished before surgical intervention. This is demonstrated by the patient in Case 4 (Fig. IO), who progressed to his final stable postoperative status despite the fact that treatment entailed protracted orthodontic care over a 3-year period. Occlusal and skeletal stability has been maintained over a 40-month postoperative follow-up period. In retrospect, treatment time could have been shortened by an anterior mandibular subapical osteotomy to level the mandibular arch after retraction of mandibular first premolars, alignment of the mandibular teeth, and partial orthodontic leveling of the mandibular arch after mandibular advancement. Clearly, the question is not necessarily “Can the deep bite be leveled orthodontically before or after surgery?” Indeed, with the use of sound orthodontic mechanics, the mandibular arch can be treated either way, or by a combination of both, and the mandible advanced into a stable relationship with the maxilla. The important question to be answered by the clinician relates to which method can be accomplished most efficiently to facilitate the overall goal of achieving vertical facial proportionality and occlusal stability.

illary deficiency: A preliminary report. J Oral Surg 35: 110.120 1977. 4. Opdebeeck H. Bell WH: The short face syndrome. AM J ORTHOD 73: 499-511,

1978.

5. Burstone C. James R, Legan H, Murphy G, Norton L: Cephalometrics for orthognathic surgery. J Oral Surg 36: 369377. 1978. 6. Legan H. Burstone C: Soft tissue cephalometric analysis for otthognathic surgery. J Oral Sug 38: 744-75 1. 1980. 7. Engel Cl, Comforth G. Damerell J, Gordon J, Levy P, McAlpine J, Otto R. Walters R. Chaconas S: Treatment of deep-bite cases. AM J ORTHOD

77:

1-13.

1980.

8. Bell WH, Jacobs JD: Surgical orthodontic correction of moderate mandibular deficiency. AM J ORTHOD 75: 481.506, 1979. 9. Proffit WB: Mandibular deficiency. In Bell WH, Proffit WB, White RP: Correction of dentofacial deformities, Philadelphia, 1980, W. B. Saunders Company, chap. 10, p. 801. 10. Bell WH, Epker BN: Surgical-orthodontic expansion of the maxilla. AM J ORTHOD 70: 517-528. 1976. 11. Jacobs J, Bell WH, Williams C. Kennedy J: Control of the transverse dimension with surgery and orthodontics. AM J ORTHOD 77: 284-306,

1980.

The authors are indebted to Ms. Carole Gardner and Mr. Kent Boughton for technical help in preparing this manuscript and photographs and also to Mr. Scott Barrows and Mr. Tom Sims for illustrations of the surgical techniques.

12. Bell WH: Augmentation of the nasomaxillary and nasolabial regions. Oral Surg 41: 691.697. 1976. 13. Bell WH, Proffit WR, White RP: Surgical correction of dentofacial deformities, Philadelphia, 1980, W. B. Saunders Company, pp. 556-581. 14. Bell WH, Scheideman GB: Correction of vertical maxillary deficiency: Stability and soft tissue changes. J Oral Surg 39: 666. 670. 1981. 15. Hogemen, KE: Cited in Willmar K: On Le Fort 1 osteotomy. Stand J Plast Reconstr Surg lZ(Supp1.): l-68, 1974. 16. Booth DF, Dietz V. Gianelly AA: Correction of Class II malocclusion by combined sagittal ramus and subapical body ostectomy. .I Oral Surg 34: 630, 1976. KL. Bell WH: Chin surgery. In Bell WH, Proffit WR. 17. McBride White RP: Surgical correction of dentofacial anaomalies. Philadelphia, 1980, W. B. Saunders Company. p. 1210. 18. Turvey A. Fonseca R: Management of soft tissues. In Bell WH, Proffit WB, White RP: Correction of dentofacial deformities, Philadelphia, 1980, W. B. Saunders Company, chap. 16, p. 1320. 19 Turvey TA. Epker BN: Soft tissue procedures adjunctive to orthognathic surgery for improvement of facial balance. J Oral Surg 32: 572. 1974. 20. Bell WH, Gallagher DM: Versatility of genioplasty with a broad pedicle. J Oral Maxillofac Surg, December, 1983. 21. Bell WH: Increasing mandibular arch length by subapical osteotomy. AM J ORTHOD 74: 276. 1978. 22. McBride KL, Sinn DP: In Bell WH, Proffit WB. White RP: Surgical correction of dentofacial deformities, Philadelphia, 1980. W. B. Saunders Company, chap. 7, pp. 200-232. 23 Bell WH, Gonyea W. Finn RA. Storum KA, Johnston C. Throckmorton G: Muscular rehabilitation after orthognathic surgery. Oral Surg 56: 229.235. 1983.

REFERENCES 1. Schudy FF: The rotation of the mandible resulting from growth: Its implications in orthodontic treatment. Angle Orthod 35: 36. 1965. 2. Sassouni V, Nanda S: Analysis of dentofacial vertical proportions. AM J ORTHOD 59: 801, 1964. 3. Bell WH: Correction of the short-face syndrome-vertical max-

Reprint reyursts: Dr. W’iliium H. Bell Universi@ of Texas Heulth Division c$ Oral Surgery 5323 Harry Hines Blvd. Dallas, Texas 75235

Science

Crnter

at Dallas