Orthodontic Principles in the Management of Orofacial Clefts
Ana M. Mercado, Katherine W.L. Vig
○ The interdisciplinary team approach was developed to provide efficient and effective integrated care for the timing and management of infants born with orofacial clefts and craniofacial anomalies.
○ The orthodontist’s role has traditionally included considerations of both skeletal and dental growth and development.
○ Management of the postnatal growth of the nasomaxillary and mandibular components has been conveniently divided and integrated into four developmental stages: neonatal maxillary orthopedics, the primary dentition, the mixed dentition, and the adolescent and adult permanent dentition.
○ The timing and sequencing of alveolar bone grafts during the mixed dentition stage and orthognathic surgery during the permanent dentition stage require close collaboration of the orthodontist with the surgeon.
○ If skeletal malocclusion is severe in the primary or early mixed dentition, skeletal correction should be delayed until the permanent dentition stage, when a combined approach of comprehensive orthodontics and orthognathic surgery may lead to a more predictable correction.
○ The maxillary incisors adjacent to the cleft site may be tipped, rotated, malformed, or hypoplastic with an absence of bone in the cleft site to support the eruption of the permanent lateral and canine teeth.
○ Orthodontic alignment of maxillary incisors before secondary bone grafting must be limited by the available bone into which the teeth can be moved.
○ In patients with a missing maxillary lateral incisor at the cleft site, the edentulous space can be closed by prosthetic replacement of the lateral tooth (with a fixed partial denture or an endosseus implant) or by orthodontic mesialization of the canine tooth (canine substitution).
Since the mid-1940s, the management of patients born with facial clefts and craniofacial anomalies has progressed from a discipline of specialists providing care independently to one of a team approach. Previously, the care of this special group of patients was delivered through independent evaluations and treatments by medical, dental, and paramedical specialists without a comprehensive, systematic, and collaborative approach. The team concept was fostered by the establishment of the American Cleft Palate-Craniofacial Association (ACPA) in 1943. The fundamental mission of the ACPA is to serve as an advocate for the team care of patients and families while promoting interdisciplinary professional education and research.
The document “Parameters for Evaluation and Treatment of Patients with Cleft Lip/Palate or Other Craniofacial Anomalies,” developed by the ACPA in 19921 and later revised in 2009,2 has provided clinicians and third-party payers with guidelines to the scope, timing, and sequencing of treatment for patients with cleft lip or palate. Within the document, the role of the orthodontist is well defined, noting that this role should be a collaborative effort with other dental, medical, and allied health professionals. Emphasis is given to the monitoring of craniofacial growth and development and to providing treatment when necessary to achieve optimal function and appearance. Delivery of orthodontic treatment is recommended in discrete stages of the skeletodental development of the craniofacial complex to prevent continuous treatment from the early mixed dentition to the permanent dentition. These concepts are further explained in texts outlining the role of the orthodontist in the management of cleft lip and palate.3,4
The purpose of this chapter is to discuss the orthodontic principles that govern the contemporary management of patients with an orofacial cleft, from diagnostic considerations to issues of timing and sequencing of treatment.
THE TEAM APPROACH
The team approach to the comprehensive care of children born with orofacial clefts requires collaboration among the orthodontist and the other members of the team (Fig. 65-1). The timing and sequencing of orthodontic care requires prioritizing each patient’s other health care needs in the context of an integrated treatment plan derived from a consensus of all team members. Orthodontic interventions may be conveniently divided into four distinct periods defined by age and dental development: neonatal period, primary dentition, mixed dentition, and permanent dentition.
NEONATAL MAXILLARY ORTHOPEDICS
Neonatal (or infant) orthopedics occurs during the early postnatal period, usually in the first few months after birth, unless contraindicated by other medical conditions. This intervention was introduced in the 1960s by Burston5 and McNeil6 with the intention that early alignment of the maxillary segments would subsequently allow the dentition to erupt into a more normal occlusion and eliminate the need for orthodontic correction. As this intervention gained popularity, the complexity of the appliances used increased, with both intraoral and extraoral components. The least invasive technique was simple extraoral lip taping (Fig. 65-2).
Fig. 65-1 The team approach for patients with craniofacial anomalies requires collaboration among many members of the team.
Fig. 65-2 An infant with a complete unilateral left cleft lip and palate. A, Defect before orthopedic intervention. B, Presurgical orthopedics with lip taping to approximate the segments. C, Postsurgical result of definitive lip repair
The benefit of this early intervention was challenged in the 1970s, but the literature also included reports of infants who also had primary bone grafts at the time of lip repair. The outcome of the presurgical neonatal orthopedics was therefore unclear, as the cephalometric measures also included those patients with primary bone grafts. By the 1980s neonatal maxillary orthopedics had fallen into disrepute as an intervention for orthodontic alignment of the segments but was espoused by surgeons as an adjunctive method of reducing cleft width and hence providing the benefits of a more facile repair, reduced operating time, and a lower risk of dehiscence in the postoperative period. The 1990s was a time of increased enthusiasm for neonatal maxillary orthopedics with the advent of presurgical nasoalveolar molding (NAM). These treatment interventions have been well described in preceding chapters.
NAM involves an intraoral molding plate, nasal stents, and extraoral taping.7,8 Intraorally, the alveolar ridges are molded to reduce the width of the cleft, achieving approximation of the segments to within 1 to 2 mm of each other. Extraorally, the simultaneous use of nasal stents and taping allows for lengthening of the columella and reshaping of the lower lateral alar cartilages in both bilateral and unilateral clefts. This orthopedic treatment prepares the infant for a one-stage primary lip-nose repair in combination with a gingivoperiosteoplasty to close the alveolar defect. The lengthening of the columella that is achieved from NAM may eliminate or reduce future surgical procedures for columellar lengthening. Because these clinical interventions are performed early in the neonatal period, longitudinal follow-up into adolescence is necessary to evaluate the long-term effects of these early interventions on subsequent nasomaxillary growth.
Inspired by the Eurocleft retrospective intercenter project of the 1990s and with advances in clinical outcomes trial methodology, the Dutch intercenter prospective two-arm randomized clinical trial (RCT), also known as Dutchcleft, was designed to study the outcome of neonatal maxillary orthopedics in subjects with unilateral cleft lip and palate (UCLP).9,10 Infant orthopedics in this trial consisted of the use of passive intraoral plates that were adjusted every 3 weeks to guide the maxillary segments and that were replaced with new plates as primary teeth emerged. In a 2005 study by Prahl et al,11 no significant difference could be found between the two randomized groups of infants up to 2 years of age with respect to feeding, nutritional status, or somatic growth. When assessing speech development at age 2.5 years, Konst et al12 found a significant improvement in children treated with infant orthopedics compared with children who did not receive infant orthopedics, with acceptable cost-effectiveness of the orthopedic treatment in regards to speech development. Further reports from the RCT indicated that infant orthopedics had no significant effect on various measures of maxillary arch dimension at ages 4 and 6 years when compared with similarly aged children who had not been treated with infant orthopedics.13 Similar findings were reported with respect to dental arch relationships at ages 4 and 6 years, including overjet, overbite, and sagittal occlusion.14 Cephalometric analyses of soft tissue, skeletal, and dental structures revealed only minor differences at age 6 years between the group treated with infant orthopedics and the untreated group.15 Facial appearance was also evaluated longitudinally in the two groups. Any group differences in facial appearance observed at age 4 years were no longer observed at age 6 years, at which time the better ratings in the infant orthopedic group could only be detected by professional raters.16 The Dutchcleft trial continues to monitor the patients longitudinally into their adolescence. In their conclusions, the investigators warned that clinicians who promote different methods of infant orthopedics, including NAM, should evaluate the long-term effects of their interventions using the rigorous methodology of an RCT.15 In their systematic review of the long-term effects of presurgical infant orthopedics, Uzel and Alparslan17 analyzed eight RCTs and four controlled clinical trials (CCTs), with follow-up periods of up to 6 years. Their results indicate that infant orthopedics has no positive effect on the treatment outcomes evaluated until the age of 6 years, including maternal satisfaction, feeding, speech, facial growth, maxillary arch dimension, occlusion, and nasolabial appearance.
If neonatal orthopedics is recommended and feasible, it should be completed in the first few months of life so that definitive surgical lip repair can be achieved within the first 6 months. Palate repair is usually delayed until later in the first year of life. An ongoing controversy relates to the balance between the advantages of restoring the anatomy of the palate in the prelinguistic period and the effects of surgical scar tissue constraining the growth and development of the nasomaxillary complex. Ross18 evaluated the outcomes of both active and passive appliances in children with UCLP at age 10 years after neonatal presurgical infant orthopedics. The results in these groups were compared with those of untreated subjects at matched ages. This cephalometric study of facial growth in treated and untreated children with UCLP reported no beneficial long-term effect of neonatal orthopedics, although some negative effects were observed in those children who had received extraoral taping. As part of the Americleft intercenter study, Daskalogiannakis et al19 found that children with UCLP who were cared for at the only treatment center among the four participating North American treatment centers that did not employ any kind of infant presurgical orthopedics as part of their primary management protocol had the largest mean maxillary prominence (SNA angle) and maxillomandibular convexity (ANB angle) during the mixed dentition stage. None of the centers that provided infant orthopedics used NAM as their presurgical approach, but rather relied on extraoral taping with or without intraoral plates. Clearly, case-controlled studies are needed to establish the long-term effect of infant presurgical orthopedics on various outcomes including growth, dentoskeletal relationships, aesthetics, and socioemotional measures, among others.
The primary dentition has usually fully erupted by the time the child is 2.5 to 3 years of age. At this age, the facial soft tissues may mask an underlying skeletal deficiency (Figs. 65-3 and Figs. 65-4). As the toddler grows into a young child, growth of the nasomaxillary complex lags behind that of the mandible, resulting in increasing midfacial deficiency. This may be reflected in the dentition as anterior or posterior crossbites. Patients with bilateral cleft lip and palate (BCLP) may have severe constriction of the posterior segments and protrusion or extrusion of the premaxillary segment (Fig. 65-5). The unilateral or bilateral crossbite may be associated with a functional mandibular shift, which is an early indicator for orthodontic treatment in the primary dentition. However, because the crossbite is likely to recur with the eruption of the permanent successors, a decision may be made to postpone orthodontic intervention until the mixed dentition.
Fig. 65-3 A, A 6-year-old girl with repaired complete bilateral cleft lip and palate. B, Her mildly prominent maxilla. C, The primary dentition. D, The bilateral crossbite. E, A palatal fistula and primary laterals that erupted ectopically behind the premaxilla.
Fig. 65-4 A, A 7-year-old boy with repaired complete unilateral left cleft lip and palate. B, His mild bimaxillary retrusion. C, The early mixed dentition period.
Fig. 65-5 A 5-year-old boy with repaired complete bilateral cleft lip and palate. A, The severe extrusion of his premaxillary segment. B, The premaxillary segment out of the vertical plane of occlusion. C, The severe constriction of the posterior segments and extrusion of the premaxillary segment. Labial and palatal oronasal fistulas are present.
Constriction of the dental arch is manifested in both the transverse and sagittal dimensions of the maxilla. Early skeletal midfacial deficiency has been addressed with some success if treated in the primary or early mixed dentition by a protraction face mask (Fig. 65-6). More recently, several studies have reported on the use of miniscrews, or temporary anchorage devices, to support the mandibular dentition while intermaxillary elastics are used to orthopedically protract the maxilla.20,21 Although the occlusal correction includes dentoalveolar proclination of the incisors, the modification and redirection of the skeletal mid-facial deficiency may be transitory. Continued growth restriction of the nasomaxillary complex results in failure to keep pace with normal mandibular growth. Consequently, malocclusion is often reestablished during the late mixed dentition and into the adolescent permanent dentition. Long-term follow up reveals biologic variability in response to the protraction facemask.22 The most logical time for the intervention is when the patient is younger than 10 years of age, during which time the circummaxillary sutures are more responsive. However, a severe malocclusion in the primary or early mixed dentition is unlikely to be corrected with growth modification, which may be a costly and unnecessary burden to the patient and result in questionable and often transient benefit. In such severe malocclusions, skeletal correction should be delayed until the permanent dentition stage, at which time comprehensive orthodontics in combination with orthognathic surgery or maxillary distraction may be more predictably reliable options.
Fig. 65-6 An 8-year-old boy with repaired complete unilateral right cleft lip and palate with sagittal and transverse maxillary deficiency. A, The lateral radiograph showed 7 mm reverse overjet. B, Protraction facemask with elastics attached to palatal hooks on expander. C, Palatal expander with bands cemented on the maxillary second primary molars and canines, with palatal hooks to attach elastics. D, Lateral and anterior crossbites improved with palatal expansion and maxillary and dental protraction. E, Facial profile after 9 months of protraction facemask therapy and palatal expansion. F, Correction of anterior and posterior crossbite; the maxillary retainer is in place. G, Superimposition of initial and postprotraction lateral cephalogram tracings shows correction of reverse overjet by incisor proclination and mild maxillary advancement. (Black lines, initial profile at age 8 years; red lines, after 9 months of protraction facemask therapy.)
Transition in the child’s dental development occurs between 6 and 12 years of age, as the primary dentition exfoliates and the permanent teeth erupt. Midfacial deficiency at this phase makes the mandible appear prognathic, thus resulting in a concave facial profile (Fig. 65-7). Eruption of the permanent teeth coincides with a period of psychosocial transition during preadolescence when the degree of friendship intimacy intensifies and independence from parents increases.23 Ward et al24 reported that the presence of an orofacial cleft decreases the oral health–related quality of life (OHRQoL) in children and adolescents. In preadolescents with craniofacial anomalies, dissatisfaction with appearance is related to social withdrawal, social anxiety, and self-consciousness.25 This is also the period during which the greatest advances have been made in restoring the bone in the cleft site through the use of secondary alveolar bone grafts, which improve the periodontal support of teeth adjacent to the cleft site and thus reduce or eliminate the need for extraction and prosthetic replacement of compromised teeth.
The orofacial cleft disrupts the dental lamina in the cleft site so that the developing permanent teeth may be missing, malformed, or supernumerary. The incisors adjacent to the cleft site may be misplaced, rotated, malformed, or hypoplastic with an absence of necessary bone in the cleft site to support eruption of the permanent lateral incisor and canine (Fig. 65-8). Alveolar bone grafting restores the continuity of the alveolar ridge and allows for closure of oronasal fistulas. Transverse maxillary constriction may be the consequence of scar tissue formation after surgical repair of the secondary palate, resulting in a characteristic omega- or V-shaped arch form, reflected in anterior and posterior dental crossbites (Fig. 65-9). A maxillary expansion appliance is often recommended when the first permanent molars and incisors erupt. Collaboration between the surgeon and the orthodontist in the mixed dentition stage to coordinate the treatment sequence assists in achieving a successful alveolar bone graft with healthy adjacent teeth.
Fig. 65-7 A, Same patient as in Fig. 65-4 at 9 years of age. B, The patient had a mild midface deficiency. C, An anterior crossbite was evident during this mixed dentition period.
Fig. 65-8 A, Repaired complete bilateral cleft lip and palate of a 7-year-old boy, before alveolar bone grafting. Partial anterior crossbite, bilateral posterior crossbites, and rotated incisors are evident. B, The patient had constricted posterior segments, oronasal fistula, prominent premaxilla, supernumerary lateral incisors located palatally, and decayed primary incisors. He required maxillary expansion before bone grafting to improve the alignment of the posterior segments with the premaxilla, selected extractions, restorative care, and a bite plane to relieve traumatic occlusion on the premaxilla. C, Maxillary and mandibular right second premolars are missing. D, A right oblique occlusal radiograph angled through the cleft shows the bony defect and a permanent lateral incisor developing in the premaxilla. E, Left side bony defect and absence of left permanent lateral incisor.
Fig. 65-9 A, The same patient as in Figs. 65-4 and 65-7, shown at age 9 years, with bilateral posterior and anterior crossbites. Note the severely rotated maxillary central incisor next to the cleft. B, The V-shaped arch form and palatal scarring.
ALVEOLAR BONE GRAFTING
Primary Bone Grafting
Primary alveolar bone grafting typically involves the placement of a bone graft in the neonatal cleft site at the time of primary surgical lip repair and hence before eruption of the primary incisors. Data suggests that this method may be deleterious to maxillary growth, so most cleft palate teams prefer to defer bone grafting until further maxillary growth and development has occurred.26
Secondary Bone Grafting
Secondary, or delayed, alveolar bone grafting is performed after primary lip repair and is classified according to the age at which the bone graft is placed: early secondary bone grafting (2 to 5 years), intermediate secondary bone grafting (6 to 15 years), or late secondary bone grafting (adolescence to adulthood).
The principles of secondary bone grafting were first introduced by Boyne and Sands.27,28 In 1986, Bergland et al29 studied 378 consecutive patients who had undergone secondary alveolar bone grafting, showing that the best outcomes were achieved in patients in whom the bone graft was performed before the eruption of the maxillary canine. This report was followed by a cephalometric study that compared maxillary growth in children who received secondary alveolar bone grafting between the ages of 8 and 12 years with the maxillary growth in children who did not have a bone graft.30 There was no adverse effect of bone grafting on anteroposterior or vertical maxillary growth, a finding attributed to the postponement of grafting until most of the growth of the anterior maxilla had occurred and to the ability of the grafted bone to develop vertically with the alveolus.30 Since the publication of these landmark articles, current opinion supports the intermediate period as the most appropriate time for grafting. This practice has the greatest benefits and least risk for interfering with midfacial and skeletodental growth and development. Levitt et al31 demonstrated that there were no significant differences in maxillary sagittal or vertical growth after secondary bone grafting in patients with complete UCLP when compared with that in patients with similar clefts who did not receive a bone graft. The multicenter Eurocleft study of treatment outcomes in patients with complete cleft lip and palate compared craniofacial form in individuals treated at five European centers.32 The only center performing primary bone grafting obtained less favorable results in vertical maxillary growth, soft tissue sagittal relationships, and soft tissue facial proportions than the centers that performed secondary bone grafting between the ages of 8 and 11 years. Moreover, the center that used primary bone grafting obtained the least favorable dental arch relationships, with almost 50% of the patients needing surgical correction of maxillary retrusion at 17 years of age.33 In Americleft, the North American intercenter study of treatment outcomes in patients with complete UCLP, the only center performing primary bone grafting obtained the least favorable dental arch relationships, lowest maxillary prominence, and least favorable maxillomandibular relationships.19,34 Further justification for performing alveolar bone graft surgery during the mixed dentition period is that patients at this age are usually cooperative with the orthodontic procedures, such as maxillary expansion, that may be indicated before grafting.35 The donor site for graft harvest, typically the anterior iliac crest, has an acceptable volume of bone for successful grafting at this age.35 A survey of alveolar bone grafting practices among ACPA teams across North America revealed a consensus for the type of alveolar bone grafting performed: most of the centers perform intermediate secondary alveolar bone grafting.26 Therefore the following discussion focuses on alveolar bone grafting during this time period.
Benefits of Secondary Alveolar Bone Grafting
Provision of Bone for Eruption of Teeth in the Line of the Cleft
A bone graft placed before eruption of the teeth adjacent to the cleft (especially the lateral incisor or canine when located on the posterior segment) provides a bony matrix to enable the eruption of these teeth into a continuous alveolar ridge, generating additional alveolar bone in the area29 (Fig. 65-10). Generally, grafting is done before the eruption of the permanent maxillary canine on the cleft side, which is usually located in the alveolar segment posterior to the cleft.
Provision of Bone for Teeth Adjacent to the Cleft
Teeth directly adjacent to the cleft, particularly maxillary central or lateral incisors located on the proximal (mesial) segment, often erupt into unfavorable positions and may be ectopic, be rotated, or have an unfavorable axial inclination. This malposition is usually a reflection of the anatomy of the alveolar cleft, which is usually narrower at the alveolar margin and wider at the piriform aperture, thus limiting the amount of bony support for the teeth, especially along the root surface directly facing the cleft. Radiographs of these teeth often demonstrate a thin layer of cortical bone along their distal surface (see Fig. 65-10), bone that may be at risk for resorption if nonjudicious presurgical orthodontic uprighting is carried out. If a bone graft is placed before extensive orthodontic alignment of erupted teeth adjacent to the cleft, crestal bone heights are preserved, and postsurgical orthodontic alignment can be accomplished with minimal risk of bone resorption while ensuring adequate bony coverage of the roots.
Closure of Oronasal Fistulas
Oronasal fistulas can allow for nasal air escape with speech and may contribute to velopharyngeal dysfunction in patients with cleft lip and palate.36 A three-layered closure technique, with the graft interposed between the two soft tissue layers, yields a high success rate of fistula closure. Surgical closure of oronasal fistulas with secondary alveolar bone grafting often results in a significant improvement in speech, manifested as decreased nasality and nasal emission.37 Occasionally, large palatal fistulas cannot be closed at the time of alveolar bone grafting without compromising the integrity of the graft. On a case-by-case basis, surgeons may elect to close the palatal fistula in a separate surgical procedure, usually before alveolar bone grafting.
Fig. 65-10 A, A bone defect at the cleft site in a 10-year-old patient before alveolar bone grafting. More than two thirds of the roots of the transposed lateral incisor and canine have developed (close to eruption). Note the thin layer of bone covering the adjacent central incisor. No orthodontic incisor alignment is planned. B, Periapical radiograph taken 4 months after alveolar bone grafting, showing excellent fill of the cleft defect with cancellous bone. The canine is erupting through the grafted bone.
Alveolar bone grafting contributes to improved nasal and lip symmetry and provides a stable platform on which the nasal structures are supported.38 If performed alone or in combination with tip rhinoplasty (often as a separate procedure) alveolar bone grafting often yields aesthetic benefits.
Reestablishment of Continuity to the Maxillary Alveolar Ridge
After a successful bone graft, the orthodontist can move the teeth bodily and upright roots into the cleft site without risk of compromising their periodontal support.29,39 The prosthodontist also can achieve a more aesthetic and hygienic prosthesis to replace missing teeth in the cleft area.39 Insertion of endosseous implants into the grafted cleft is possible and provides functional stimulation to the transplanted bone.40
Stabilization of Maxillary Segments
Patients with bilateral clefts present with varying degrees of mobility of the premaxilla, which usually remains unstable throughout life.29 In such cases, secondary alveolar bone grafting stabilizes the premaxilla, allowing patients to have functional incisors with adequate stability to serve as abutments for fixed prostheses.29,39
Dental and Orthodontic Considerations Associated With Secondary Bone Grafting
The optimal time for performing secondary alveolar bone grafting can be established according to the age of the patient or, alternatively, according to dental development as defined by stage of root development.
Chronologic Age By definition, secondary bone grafting is done during the mixed dentition stage, before the eruption of the maxillary canine (or lateral incisor, if located in the alveolar segment posterior to the cleft). Once teeth have erupted into the cleft site, their limited periodontal support will not improve with a graft, because the transplanted bone will not adhere to the tooth surface.35 The height of the crest of alveolar bone eventually resorbs to its original level. It is therefore essential to perform the graft before the eruption of the permanent teeth adjacent to the cleft. This period may encompass a range of several years, from age 6 to 15 years, when grafting has a high success rate. However, evidence shows that the older the patient is at the time of surgery, the poorer the outcomes of secondary bone grafting.41 Therefore the available evidence supports an optimum age at which patients should receive bone grafts. Using chronologic age alone for defining the optimal age for grafting may not be clinically valid, because patients with cleft lip or palate have delayed development of the teeth compared with individuals without clefts.42 Moreover, teeth adjacent to the cleft side demonstrate more developmental delay than the contralateral teeth.42 Dental development, based on assessment of the number of permanent teeth erupted and the extent of root formation, represents a more accurate indicator of the optimal timing for the bone grafting procedure than does chronologic age alone.
Maxillary Canine Development One developmental indicator that has been proposed for establishing the optimal timing for grafting is the root formation of the permanent maxillary canine on the cleft side. It has been recommended that the optimal timing for secondary grafting is when the maxillary canine has developed one half to two thirds of its final length, which generally occurs between the ages of 8 and 11 years39,43 (see Fig. 65-10). This is advocated because when the root has developed two thirds of its expected full length, accelerated eruption of the canine occurs, and it can then erupt spontaneously through the graft, bringing additional alveolar bone into the area. In a retrospective study of patients with non-syndromic UCLP, Mercado et al44 demonstrated a significant positive correlation between stage of canine root development at the time of surgery and the outcome of bone grafting.
Maxillary Lateral Incisor Development A study of patients with UCLP demonstrated that the cleft-side permanent lateral incisor was present in 50.2% of patients.45 Of these patients, 76.5% had the permanent lateral incisor located on the posterior segment, distal to the cleft. When the maxillary lateral incisor is located in the posterior segment, alveolar bone adjacent to the cleft is generally insufficient to support the lateral incisor as it drifts anteriorly and occlusally along its eruptive path into the arch. In such cases, grafting before the eruption of the lateral incisor may be advisable to improve the prognosis of this tooth.46,47 The developmental indicator of one half to two thirds of canine root formation for timing of an alveolar bone graft may be too late when the aim is to preserve an existing lateral incisor. Lilja et al48 discourage the use of root formation as an indicator for graft placement, proposing the assessment of the thickness of bone covering the crown (of the lateral incisor or canine) to determine timing of bone grafting. They advocate that bone grafting be performed when there is a thin layer of bone covering the tooth distal to the cleft. Other studies have reported no significant relationship between the degree of radiographic canine eruption through the alveolar cleft and the outcome of secondary bone grafting.49,50
The sequencing of procedures associated with placement of an alveolar bone graft requires interdisciplinary communication and cooperation for a successful outcome. Orthodontists, general or pediatric dentists, oral surgeons, and plastic surgeons intervene in a coordinated fashion to ensure that one discipline’s efforts do not interfere, delay, or jeopardize those of the other disciplines.
Parents and caregivers may be concerned about teeth (often supernumerary) that have erupted near the cleft, either palatally or high in the labial vestibule. Ectopic teeth present a challenge for the parents and patient to maintain good hygiene because of their location and limited accessibility. The role of the general or pediatric dentist is to ensure that the patient and parents are aware of the ectopic teeth and that they are instructed on good oral hygiene practices to maintain the teeth free of decay, out of traumatic occlusion, and not contributing to traumatic ulcerations of the surrounding mucosa. The preservation of these teeth before surgery maintains the supporting alveolus. The general or pediatric dentist should restore any decayed teeth adjacent to the cleft before the grafting procedure. On the other hand, erupted teeth adjacent to the cleft that have poor periodontal or restorative prognosis should be extracted at least 2 months before surgery to allow the soft tissues to heal (see Fig. 65-8). This will allow healthy mucosal flaps to be reflected, positioned, and sutured over the grafted bone at the time of surgery.
Healthy ectopic primary or supernumerary teeth that have erupted along the line of the cleft should also be removed at least 2 months before surgery to allow access to the surgical site. Orthodontic treatment may be required presurgically to reposition maxillary teeth that are in traumatic occlusion or to expand a severely constricted maxilla, thus providing the surgeon better access to the cleft defect.
In bilateral cases, a mobile premaxilla with anterior traumatic occlusion may need to be addressed with a posterior bite plane to minimize mobility, which may compromise the success of the grafts during the healing period.35 A severely extruded premaxilla may need to be intruded to level it with the posterior segments (Fig. 65-11). This can be done with an active intrusion arch ligated over a passive segmental wire to the maxillary incisors. Alternatively, miniscrews placed directly on the premaxilla may serve as a point of attachment during intrusion, repositioning, and stabilization of the premaxilla.20 Other surgical procedures such as minor aesthetic revisions of the nose and lip, as well as the insertion of tympanostomy tubes, may be undertaken during the same general anesthesia setting of the alveolar bone graft. Dental prophylaxis and restorative work are generally not performed in conjunction with the bone grafting procedure to minimize the release of bacteria and debris into the surgical site. Unerupted teeth with poor prognosis adjacent to the cleft can be removed by the surgeon intraoperatively once the mucosal flaps have been reflected.
Fig. 65-11 A, The same patient as in Fig. 65-5 at 9 years of age, after orthodontic treatment to expand the maxillary arch and intrude the premaxilla. Note the improved facial aesthetics. B, The patient had improved vertical alignment of the premaxilla with the posterior segments. Permanent lateral incisors are congenitally missing. C, Adequate expansion of the posterior segments in alignment with the premaxilla. Palatal oronasal fistulas are more obvious after expansion.