Nasoalveolar Molding and Columella Elongation in Preparation for the Primary Repair of Unilateral and Bilateral Cleft Lip and Palate

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Nasoalveolar Molding and Columella Elongation in Preparation for the Primary Repair of Unilateral and Bilateral Cleft Lip and Palate

Judah S. Garfinkle, Barry H. Grayson

KEY POINTS

Early treatment, initiated within 2 to 4 weeks after birth, is key to take advantage of cartilage plasticity. Starting nasoalveolar molding (NAM) after 8 weeks of age results in less predictable outcomes.

NAM should be evaluated as a unique treatment intervention with unique outcome measures rather than grouped with the other forms of presurgical infant orthopedics.

NAM is indicated for all cleft nasal deformities, even incomplete cleft lip and palate with well-aligned alveolar ridges.

The goals of NAM for patients with unilateral clefting are to make the nose more symmetric and improve nasal tip projection.

The goals of NAM in patients with bilateral clefting are to improve nasal symmetry and nasal tip projection, reduce the width of the nasal tip, and achieve nonsurgical columella elongation.

By presurgically reducing the severity of the cleft deformity, the surgeon will be able to achieve the best functional and aesthetic outcome.

The focus of this chapter is primarily on the role of the orthodontist (or other dental professional) during the presurgical management of an infant born with clefts of the lip, alveolus, and palate. The first section provides a general description of clefting and its early clinical management to provide a foundation for the presurgical orthopedic treatment intervention. A historic perspective on presurgical infant orthopedics (PSIO) introduces the rationale for nasoalveolar molding (NAM). The remainder of the chapter focuses on the specific clinical procedures, complications, and benefits of NAM. An evidence-based approach is offered whenever possible.

Although every member of the interdisciplinary cleft palate team has a specialized role, the team functions best when each clinician becomes an informed novice in the other team members’ specialties. We aim to provide sufficient explanation of the theory and technique of NAM that each team member is able to better integrate this component into their overall understanding of the management of patients with clefts.

BACKGROUND

Demographics

Clefts of the lip, alveolus, and palate represent a group of the most common congenital anomalies of the craniofacial skeleton. The incidence ranges from approximately 1 in 500 to 1 in 1000 births, depending on the specific condition as well as on racial and ethnic circumstances. Although the physical impact of a cleft appears well localized, many seemingly different (but ultimately connected) anatomic systems are affected. To satisfactorily address the constellation of treatment issues, the expertise and care of an interdisciplinary cleft palate team is required so the most favorable treatment sequence can be developed and implemented for each individual patient based both on their specific physical and psychosocial needs and their respective stage of growth and development. The treatment for a patient with an orofacial cleft often spans the first two decades of life and involves intervention by every member of the cleft team.

Etiologic Factors

Although the phenotypic aberration resulting in cleft lip and palate has been well characterized, the ultimate cause is still being investigated. Currently, both genetic and environmental factors have been implicated in the etiology of clefting disorder. In regard to the physical disturbance to normal growth and development, cleft lip results when the medial nasal and maxillary processes fail to fuse during the fifth week of embryonic development. Between the eighth and twelfth week of fetal development, failure of the right and left palatal processes to assume the proper horizontal orientation and fuse results in the palatal defect. Although all cleft anomalies are a product of similar alterations to normal fetal development, great variability in clinical presentation exists.

Presentation of the Cleft Deformity

A cleft lip can range from a slight soft tissue notch to a profound absence of both hard and soft tissue involving the lip, alveolus, and anterior maxilla. Clefting of the palate can include the hard palate, the soft palate, and the uvula. The further anterior the palatal clefting begins, the more structures will be involved. Both lip and palatal clefts will occur to a variable extent on one (unilateral) or both (bilateral) sides.

The clinical hallmark of unilateral cleft lip and palate (UCLP) includes not only clefting of the upper lip and alveolus, but a distorted nasal form as well. Absence of the tissue at the base of the nose that normally tethers the medial and lateral aspects of the nostril aperture together results in a widened and flattened nostril. The tip of the nose loses its sagittal projection, and the columella deviates to the noncleft side with the greater lip and alveolar segments. The medial aspect of the greater alveolar segment is often displaced slightly superiorly. The nasal septum deviates to the noncleft side (Fig. 64-1).

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Fig. 64-1 A, Initial presentation of a patient with complete unilateral cleft lip and palate. B, Complete unilateral cleft lip and palate. Note the absence of the tissue at the base of the nose that normally tethers the medial and lateral aspects of the nostril aperture together results in a widened and flattened nostril. The tip of the nose loses its sagittal projection and the columella deviates to the noncleft side with the greater lip and alveolar segments. The lower lateral alar cartilage on the cleft side drops down at the nostril apex and often takes on a concave form. The medial aspect of the greater alveolar segment is often displaced slightly superiorly. The nasal septum deviates to the noncleft side. C, The patient after nasoalveolar molding. Note the increase in nasal tip projection and columella length on the cleft side. Improved nasal symmetry and approximation of the lip segments at rest has been achieved. In addition, the alveolar cleft gap has been closed with the alveolar segments in passive contact. The increased surface area (after nasoalveolar molding) of the nasal mucosal lining facilitates surgical repositioning and retention of the nasal tip cartilage.

Complete bilateral cleft lip and palate (BCLP) is characterized by some amount of dorsiflexion or rotation of the premaxillary segment, which is tethered to the tip of the nose, absent of any distinguishable columella. The nose is deficient in sagittal projection and widened because of the connection of the lateral aspects of the nasal cartilages to the remaining lateral lip segments. The prolabial tissue patch, attached to the tip of the nose, often appears reduced in overall volume (Fig. 64-2).

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Fig. 64-2 A, The extraoral initial presentation of a patient with bilateral cleft lip and palate (BCLP). Note the absence of the columella and displacement of the premaxilla and prolabium. B, Bilateral anatomic deformity, specifically the displacement of the lower lateral alar cartilage and subsequent deposition of fibrofatty tissue between the nasal tip cartilage and deficiency of the columella and displacement of the premaxilla. C, The intraoral initial presentation of a patient with BCLP. Note the extraoral position of the rotated premaxilla and prolabium, discontinuity of the lip and alveolar segments, and complete bilateral palatal clefts. D, A patient with BCLP after nasoalveolar molding and nonsurgical columella elongation. Note the change in columella length, repositioning of the premaxilla, and approximation of the lip segments at rest. E, A patient with BCLP after nasoalveolar molding. Note the increased length of the columella, reduction in the width of the nasal tip, and the increased nasal tip projection.

OBJECTIVES OF PRESURGICAL INFANT ORTHOPEDICS

Lip, Nose, and Alveolus

The ultimate treatment goal in the management of clefting disorders is to restore both normal function and aesthetics. A challenging component in the aesthetic repair of UCLP is in re-creating normal lip and nasal anatomy. Proper approximation of the vermilion border and reconstruction of the philtral column, without causing excessive scar tissue, is the primary objective for lip reconstruction. Obtaining greater sagittal projection and symmetric nasal anatomy, both in size and shape of the nasal apertures, are the primary objectives for the nose. Because of the symmetry inherent in the BCLP anomaly, attainment of a symmetric lip and nose repair is relatively simple. The challenge in BCLP is obtaining normal nasal anatomic relationships, specifically an aesthetic columella, adequate nasal tip projection, and appropriate narrowing of the nasal tip and base. An additional objective of NAM is presurgical alignment of the alveolar segments, including the premaxilla in BLCP. This often enables closer approximation of the overlying soft tissues, reducing tension across the lip repair, and affords the opportunity to perform a gingivoperiosteoplasty (GPP) with minimal tissue undermining.

Reducing the Severity of the Deformity Before Surgery

The desired outcomes for the lip and nose are more attainable from a surgical perspective when the initial deformity is mild rather than severe. In a mild deformity, the wounds heal under less tension, tissue deficiency is reduced, and the anatomic foundation underlying the cleft more closely resembles the structures in normal configuration. Clinicians have been grappling with cleft severity for hundreds of years and have attempted various methods to reduce the severity of deformity before the primary surgical repair.

HISTORIC PERSPECTIVE ON PRESURGICAL INFANT ORTHOPEDICS

Inherent in the term presurgical infant orthopedics is the concept of altering the position or the shape of the cleft maxillary alveolar ridges before surgery. Although the alveolar segments were the primary target of such treatment, the overlying soft tissues were affected by treatment as well, resulting in closer proximity of the lip segments and, to a lesser extent, the base of the nose.

Evolution of Presurgical Infant Orthopedics

Generating the necessary force system for efficient PSIO presented a biomechanical challenge. Originally, force was generated from an extraoral appliance system. In the late seventeenth century, Hoffman described the use of an appliance anchored to a head cap to retract the premaxilla in BCLP cases. Since then, various advancements have been made to extraoral anchorage devices, some of which are still used today, primarily in bilateral cleft cases. In the 1950s, McNeil1 described an intraoral molding plate to achieve “preoperative reduction of the width of the palate cleft by non-surgical means.”2 Obtaining adequate retention and generating the desired force system proved challenging. In 1975 Georgiade and Latham3 proposed the use of a pin-retained intraoral appliance to achieve presurgical maxillary arch alignment in patients with bilateral clefts. This device promised to offer three-dimensional control. A few years later, Latham4 introduced a pin-retained appliance to align the alveolar segments in patients with unilateral clefts as well. The pin-retained appliance has gained much attention and is still in use today, although it has as many opponents as proponents. During this time Hotz5,6 and Hotz and Gnoinski7 continued to work with “passive” molding plates, referred to as the Zurich appliance, and reported successful treatment outcomes. For the last 20 years, most of these techniques, with some modifications, have remained in use in cleft centers all over the world. In addition, lip adhesion surgery and lip taping have been shown to reliably produce orthopedic movement of the alveolar segments and are currently advocated at some cleft centers.8,9

All of the previously mentioned PSIO techniques, spanning the last 300 years, share at least one thing in common: The desired effect was ultimately a better treatment outcome for patients with cleft lip and palate. Had the first attempt achieved this goal, it is likely that no others would have followed.

Controversy of Presurgical Infant Orthopedics

Multiple PSIO treatment techniques have been proposed over the years, because no solution has proved to be completely satisfactory. Part of the difficulty results from conflicting definitions for the various commonly used clinical terms (such as active versus passive appliances). In addition, little consensus exists on the definition of clinical success. This ultimately adds to the variability in treatment protocol. For example, if one cleft team prioritized achieving approximation of the alveolar segments before the primary surgical repair, some type of alveolar molding appliance would be indicated. In contrast, this may be viewed as unnecessary by another team without a similar treatment goal.

Caution and responsibility need to be exercised when interpreting and analyzing research in the field of PSIO. PSIO is an umbrella term used to refer to all presurgical infant orthopedic techniques. Too often, results about one of the treatment techniques are wrongly referred to and applied to the other techniques. Each PSIO treatment approach should stand on its own merits and be judged based on its own definition of success.

For example, the Dutchcleft study has produced a wealth of information about PSIO in unilateral cleft lip and palate and its relation to facial growth; facial appearance; maternal satisfaction; maxillary arch dimensions; feeding, weight, and length; and occlusion.1015 This study has shown that the use of a passive alveolar molding plate has no lasting advantage or disadvantage in terms of the specifically defined clinical outcome measures. However, the Dutchcleft study had limitations. In this prospective randomized multi-center study, the PSIO technique used was a passive alveolar molding plate. Therefore, the conclusions drawn from the study can only be valid in cases of passive alveolar molding therapy.

The Dutchcleft study serves as a model for cleft research and has been well received. However, the data should not be interpreted in relation to, or applied to, other forms of PSIO. Many clinicians wrongly interpret the results of the Dutchcleft study to mean that the entire concept of PSIO should be abandoned. However, the Dutchcleft study did not include a treatment center in which NAM was performed. The study did not include patients treated with an appliance that was intended to correct the shape of the nasal cartilages and elongate the columella. Therefore, the outcomes of Dutchcleft do not apply to NAM, which requires evaluation on its own merit.

Despite advances, the scientific and professional debate on the use of PSIO will continue until we adopt a shared definition and precise use of the clinical terminology, along with a common definition of clinical success.

Neonatal Tissue Plasticity

Although aesthetic restoration of the cleft nose deformity was recognized as one of the greatest surgical challenges, limited clinical attention was directed to address this problem presurgically. Drawing on their experience and success with malformed auricular cartilage molding, in 1988 Matsuo and Hirose16 described a technique for molding the nasal cartilage after initial lip repair at approximately 1 week of age through insertion of a custom-made nasal stent. The stent was to remain in the nose for 3 months. This technique depended on surgical construction of a nasal floor for retention of the nasal stent. The proposed biologic process that would enable effective molding of the nasal cartilage (and auricular cartilage) was the elevated level of maternal estrogen in the newborn infant resulting in an increased level of circulating hyaluronic acid, which ensures cartilaginous plasticity. In 1991, Matsuo and Hirose17 demonstrated a technique for presurgically molding nasal cartilage in cleft patients who have a Simonart’s band; the band served as the nasal floor necessary for stent retention. Although the work by Matsuo and Hirose finally addressed the nasal deformity presurgically, the method had many drawbacks. The technique could only be used for patients with a unilateral cleft and a Simonart’s band; furthermore, the alveolar defect, which is primarily responsible for the overlying soft tissue asymmetry, was not addressed. The treatment challenge to incorporate both nasal cartilage and alveolar segment molding in unilateral and bilateral cleft cases remained unsolved.

A Novel Approach to Presurgical Infant Orthopedics

In 1993, Grayson et al18 described a technique of PSIO that not only addressed the alveolar and lip segment approximation before surgery, but established specific presurgical treatment goals regarding correction of the nasal cartilage asymmetry and increasing the length of the deficient or absent columella. The treatment modality was refined and illustrated further by Grayson and colleagues in 199919 and 200120 and termed nasoalveolar molding (Figs. 64-3 and 64-4). As discussed previously, the plausibility and rationale for this treatment approach was borne out of the work of Matsuo and colleagues involving infant auricular and nasal cartilage plasticity, as well as the principles underlying tissue expansion and the previous PSIO strategies.

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Fig. 64-3 Evolution of the unilateral nasoalveolar molding (NAM) appliance. A, The initial NAM appliance was retained by palatal undercuts and tissue adhesive. Note the absence of a retention button. The intranasal portion lacked the bilobed form currently in use. B, Note the addition of retention buttons to the acrylic nasal stent that entered the nose from an extraoral approach. C, Current version of the NAM appliance. Note that the nasal stent is fabricated out of wire and acrylic, the single retention button, the hole in the middle of the palatal acrylic, and the bilobed intranasal portion of the nasal stent.

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Fig. 64-4 Evolution of the bilateral nasoalveolar molding (NAM) appliance. A, The initial bilateral cleft lip and palate (BCLP) NAM appliance. Note that the intranasal portion of the nasal stent is not bilobed. The armature of the nasal stent is made of acrylic. The horizontal columella band is fabricated on an elastic chain and secured with steel buttons. B, During a transitional evolution, the horizontal columella band was fabricated with acrylic and the nasal stent armature was fabricated out of wire. C, The current version of the BCLP NAM appliance. Note that the nasal stent armature is fabricated out of wire and the intranasal portion of the nasal stent is bilobed. In the middle of the palatal acrylic is a hole, which serves to maintain a patent airway should the posterior portion of the appliance drop down onto the tongue.

Over the past 20 years, the technique of NAM has become widely accepted around the world. Many investigators have published their clinical experiences and various treatment modifications.2133 Although some controversy remains surrounding the long-term benefits in relation to the costs of NAM (and PSIO in general), the discussion is important to allow clinicians and families to more specifically define treatment goals and outcomes.

TREATMENT OBJECTIVES OF NASOALVEOLAR MOLDING

NAM is focused on reducing the severity of both the hard and soft tissue cleft deformity before surgery. This includes addressing alveolar, lip, and nasal abnormalities.

Alveolar Process

Reducing the width of the alveolar cleft serves to bring the overlying soft tissues closer together, facilitating closure of the lip and palate. An additional objective of NAM in infants with BCLP is the presurgical alignment of the premaxilla. Often the premaxilla is ectopically positioned out of the mouth or is deviated to one side. NAM permits centering of the premaxilla and retraction into the oral cavity. Furthermore, NAM prevents downward displacement of the premaxilla, which reduces the possibility of an impinging deep bite. NAM also prevents medial collapse of the anterior aspect of the posterior alveolar segments, reducing the risk of the premaxilla being blocked out anteriorly from the maxillary alveolar arch form. Narrowing the alveolar cleft can facilitate performing a minimally invasive GPP.

The Lips

The relationship of the lip segments and the medial and lateral aspects of the alar base improves as the alveolar segments come into alignment. The objective of NAM is to have nearly passive contact of the lip segments and improved nasal symmetry before the primary surgical repair of the lip and nose (see Fig. 64-1, A and C, and Fig. 64-2, A and D). In this way, the surgeon is able to approximate the soft tissues with less tension and more precision, resulting in a superior aesthetic outcome. In support of this surgical premise regarding the benefits of reducing the tension in healing surgical wounds, Burgess et al34 reported that tissues healing under less tension produce narrower scars.

Nose and Columella

The NAM appliance consists of an intraoral molding plate and a nasal stent. The nasal stent serves to increase nasal tip projection, establish proper curvature of the alar cartilage through molding, and increase the internal surface area of the nasal mucosal lining through tissue expansion. An attempt is made to overcorrect the anterior projection of the nasal tip and the position of the apex of the nostril aperture in anticipation of some degree of relapse associated with postsurgical scar contracture. In unilateral cases, approximation of the alveolar ridges and lip segments results in reducing the degree of columella deviation to a more upright orientation, facilitates repositioning the deviated columella in an upright orientation. An additional benefit to nasal stenting reported by many parents is increased nasal airflow through the cleft nostril.

Most bilateral cleft patients are born with a severely deficient or absent columella. The displaced prolabium and premaxilla emerge directly from the tip of the nose. The traditional surgical procedures used to create a functional columella result in a scarred and tethered nose with limited anterior or superior projection of the nasal tip.35 Over the long term, this results in an acute nasolabial angle and a broad and retrusive nasal tip. The surgically constructed columella is also unusually wide with noticeable scarring. The bilateral nasal stents of the NAM appliance, with a combination of taping techniques, provide for nonsurgical columella elongation before primary lip and nose surgery. This process results in improved nasal aesthetics, including a scar-free columella, enhanced nasal tip projection, and narrowing of the alar base, which has long-term benefits for nasal growth and development (Fig. 64-5).

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Fig. 64-5 Long-term follow-up of nasal morphology, including columella length and nasal tip projection, after nasoalveolar molding (NAM) in a patient with bilateral cleft lip and palate. A, Initial presentation at 2 weeks of age, before NAM therapy. B, At 1.5 months of age during NAM therapy before surgery. C, At 2 years of age. D, At 10 years of age. E, At 12 years of age.

CLINICAL TECHNIQUE OF NASOALVEOLAR MOLDING

Diagnosis

The primary step in preparation for NAM is obtaining the proper diagnosis. It is estimated that 10% of clefts are associated with one of more than 300 possible syndromes, many of which may be associated with medical conditions that require treatment. Although NAM is an important step in the initial therapy of these infants, sometimes more pressing health issues should be addressed immediately after birth. Once the infant’s health status has been confirmed and stabilized, the family and their social support structure should be assessed.

Family Support

NAM therapy requires considerable time and effort on behalf of both the family and clinical staff. The parents must be committed to making weekly or bi-monthly appointments for the serial NAM adjustments. In addition, the process of applying face tapes and cleaning the appliance requires hours of dedication at home during the time immediately after birth through the first 3 to 5 months of life. A high level of parent cooperation is required to attain success with this technique. Successful treatment outcomes do not correlate with socioeconomic status or traditional family structures.

Intraoral Examination

The final step before treatment begins is a comprehensive intraoral examination. This is best accomplished with the surgeon and orthodontist examining the infant together. The specific anatomic cleft variation needs to be documented and its implications for treatment considered. A precise description of the nasal, labial, alveolar, and cleft anomalies should be noted in the patient record and photographed. Simonart’s bands, ectopic neonatal tooth buds, and any other remarkable findings should be recorded. This step is essential for proper treatment planning, because it will establish the specific treatment goals. For example, if the palate is nonclefted and the alveolar segments are in good alignment, the NAM treatment will focus on nasal stenting alone. Closure of an alveolar gap is a more significant challenge if the palate is intact or if the infant presents at an older age (4 to 5 months). These variables in the presentation of clefting help to delineate the specific treatment goals. The clinical examination, a specific diagnosis, and a comprehensive treatment plan inform the clinician and parents of the possible treatment outcomes, costs, and risks and benefits of the procedures before initiating treatment. This enables the proper informed consent to be obtained.

Maxillary Impression

A maxillary impression and medical photographs are among the first clinical steps taken. This is accomplished in a hospital setting with the surgeon, orthodontist, and a dental assistant working together. Proper emergency airway and resuscitation protocols are essential, as is having the appropriate equipment assembled in advance, should it become necessary. First, an impression tray is fit to the maxillary arch, ensuring adequate transverse and sagittal extensions. The infant’s head is centered, with the hands and feet restrained, while the tray is fit. The surgeon turns the baby upside down while the impression is performed (Fig. 64-6, A). The infant’s airway is maintained with a dental mirror handle gently applied to the dorsum of the tongue. The inside of the infant’s oral cavity is well illuminated during the procedure, which enables the clinician to see the functioning airway back to the posterior pharyngeal wall. It is important to eliminate excessive impression material in the posterior aspect of the tray to minimize the risk of material breaking off in the infant’s mouth. A generous amount of material is needed in the anterior portion of the impression tray to manipulate it around the alveolar segments and the premaxilla. The more accurately the impression characterizes the anatomy, the more exact the fit can be with the appliance. Once the impression material is set, the tray is removed and the oral cavity examined for any excess impression material that may have remained in the nose or cleft. The maxillary impression is taken with a polysiloxane putty material (type 0). We also regularly obtain a nasal impression with a light-body vinyl polysiloxane material as part of the initial record set (Fig. 64-6, B).

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Fig. 64-6 A, Maxillary impression technique. Note the baby is held upside down and a patent airway is actively maintained with the handle of a dental mirror. B, Nasal impression technique. Note the capture of the medial canthi in the impression to later serve as a source of anatomic orientation.

Appliance Fabrication

A maxillary cast is fabricated using dental stone. Undercuts are blocked out with utility wax. Self-curing acrylic is then used to fabricate the intraoral molding plate, or alternatively, the appliance can be fabricated with biocryl. Once set, the gross acrylic excess is removed, the vestibular extensions are reduced 2 to 3 mm from the height of the vestibular fold, and a relief is made for the frenal attachments. A 6 mm diameter hole is placed through the plate in the midline approximately 10 mm from the posterior border. This hole maintains a patent airway should the NAM appliance drop down onto the tongue and possibly be pushed forward into an upright position. The appliance is then polished and ready for the delivery appointment.

Appliance Delivery

Extra time is scheduled for the delivery appointment because so much must be accomplished. The tray needs to be adjusted for fit and the retention button or buttons attached. The parents need to be instructed in the care and use of the NAM appliance, including retention taping procedures, oral hygiene, and how to perform an intraoral examination. Time needs to be budgeted for questions that the parents will have.

Before placing the NAM appliance in the infant’s mouth, the clinician should run his or her finger over all the surfaces to ensure a smooth finish and that no sharp angles exist anywhere on the plate. The plate must be viewed on the stone cast to verify that the necessary reduction has been made in the vestibular extensions and for the frenal attachments. The plate is now ready to be inserted in the mouth. It can be helpful to have a parent hold the infant’s hands next to his or her ears so the head can be held still while the hands are restrained. Long cotton-tipped applicator sticks and a penlight are very effective for the intraoral examination. With the plate in the mouth, gentle occlusal pressure is applied to the undersurface. The lips must be retracted so the relationship of the plate’s margins to the surrounding tissues can be assessed. Then the plate is removed so necessary adjustments can be made with a low-speed hand drill and acrylic bur.

It is helpful if the infant is hungry toward the end of the initial delivery appointment so that the caregivers can attempt a feeding while still at the clinic to ensure that the baby is comfortable before returning home.

Retention Button

The retention button should be placed on the anterior surface of the molding plate, midway between the cleft lip segments, so it does not impede approximation of the lips as they are brought together. The button should be placed at a 30- to 40-degree angle to the occlusal surface of the alveolar ridges to achieve proper retention and avoid unseating of the appliance from the palate. To determine the length of the button, the distance from the most anterior aspect of the plate to approximately 3 to 5 mm past the lips is measured. An indentation is created on the plate at the point that the button will be attached. An acrylic mix of self-curing resin is used to fix the button in place. Immersing the appliance in a hot water bath can greatly decrease the setting time of the self-curing resin. The new addition of acrylic is refined, ensuring it is smooth and that retention of the button is adequate. The appliance should be rinsed before it is placed in the mouth after making additions or adjustments. The appliance is then inserted again, this time with the retention tapes attached. The measure of proper retention is that the appliance remains adherent to the palate. Optimal positions for the button and tapes should also be confirmed (Fig. 64-7).

Face Tapes

Proper taping technique should provide adequate retention for the NAM appliance with a minimum of discomfort to the infant’s skin. Because the “active” tapes that provide for retraction and molding force with elastic rubber bands need to be changed one time per day, a “base” tape is placed on each cheek. This base tape is usually replaced one time per week, allowing more frequent placement and removal of the active retraction tape without causing excessive skin irritation. The active retraction tape is fabricated by taking a ¼-inch Steri-Strip and doubling it back on itself at one end, around an elastic orthodontic rubber band. The elastic, measuring 3/16 inch, is calibrated to deliver approximately 4 oz of force when stretched 20 to 30 mm (Fig. 64-8, A). The parents are shown where to position the base and active tapes to optimize NAM appliance retention and instructed to clean the appliance at least once per day with warm water. Although it may seem traumatic to apply tapes to the infant’s cheeks, the alternative approaches for appliance retention (an extraoral cap, placement of retention pins into the alveolar ridges, or considerable amounts of a denture adhesive) are in most cases inferior alternatives to cheek taping (Fig. 64-8, B and C).

May 11, 2019 | Posted by in Oral and Maxillofacial Surgery | Comments Off on Nasoalveolar Molding and Columella Elongation in Preparation for the Primary Repair of Unilateral and Bilateral Cleft Lip and Palate
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