Presurgical Infant Orthopaedics - Journey So Far

Cleft lip and palate (CLP) are the most common congenital
malformation caused due to variation in development of facial...


Introduction
Cleft lip and palate (CLP) are the most common congenital malformation caused due to variation in development of facial structure during gestation [1]. The incidence of patients with CLP is about 1.7 in 1000 live births globally [2]. The incidence is highest in Afghan population as 4.9 and lowest in Negroid population as 0.4 per 1000 live births [3,4]. The presence of cleft involving lip, palate and alveolus results in disfigurement and distorted growth and development. There is wide presentation of facial features among patients depending upon the severity of the cleft. A wide nostril base, separation in the upper lip of the cleft side is the characteristic feature of unilateral cleft defect. There is lateral and inferior displacement of affected lower lateral nasal cartilage which results distortions in the anatomic form of nose, tripod tilt in skeletal structure, a depressed dome, increased alar rim and deformities in apex of nostril. Shift in the base of the nose, deviation of septum to non-cleft side is also seen in patients with CLP. The separated premaxilla may overhang from the maxilla with variation in size [5,6]. Supervision and management of patients with CLP is a process that begins in infancy and continues in adulthood. Early treatment in the form of Presurgical Infant Orthopaedics (PSIO) is required to reduce the cleft width and to help maxillary arch development, thereby improving occlusion, feeding, speech, hearing, and language development and aesthetics [6,7]. PSIO has been defined as "use of forces to reposition tissues secondarily displaced due to a cleft deformity" [8]. Active and passive orthopaedic appliances have been developed for correction of CLP defect by using compressive & tensional forces or passively guiding growth. The aim of PSIO is to decrease the width of the cleft gap, to achieve a favorable alignment in the cleft segments within the initial few months of infancy prior to cheiloplasty, and to allow surgical repair with minimal tension [9]. In addition, there is improvement and ease in feeding, increased fluid intake, subsequently weight gain, improvement in functioning of tongue, reduced risk of aspiration and reduction in severity of dental & skeletal deviations.  [10,11]. Adhesive tape binding usage in presurgical preparation was popularized by Hullihen [12]. Brophy in 1927 clinically demonstrated that silver wire passing cleft alveolus can be gradually tightened to approximate the alveolus before lip repair [13]. The modern school of presurgical orthopaedic to mould the alveolar segments using a series of plate system with active forces was introduced by 1950 McNeil [14] later popularized by Burston. Cupid's bow and the philtrum symmetrical correction as Millard's rotation advancement closure technique was introduced by Millard in1960 [15]. A pinretained active appliance which could simultaneously help in retraction of premaxilla and expansion of the posterior segments was introduced by Georgiade and Latham in 1975 [16]. The use of a passive orthopaedic plate for slow alignment of the cleft segments was described by Hotz in 1987 [17]. Matsuo's (1988-91) series of research on molding of neonatal nasal cartilage and nostril with the help of silicone tubes was the gateway to invent newer modern methods [18][19][20]. The paradigm shift in the PSIO treatment was with the introduction of Nasoalveolar molding (NAM) by Grayson and Cutting in 1993, a novel technique in which presurgical molding of the alveolus, lip and nose is carried out in infants born with CLP [21].

Objectives of PSIO
Literature has highlighted the objectives of PSIO: to stimulate growth of patalal shelves, upper arch development, improvement in the projection of nasal tip leading to overall growth of the face. It also facilitates improvement in occlusion, feeding, speech, hearing, and language development. Eventually, PSIO aim at achieving a more uniform osseous base. The achievements of these objectives facilitate surgical closure and improve the final aesthetic result [22][23][24][25].

Classification of PSIO appliances
PSIO appliances can be classified into active and passive appliances based of force application (Table 1). Active appliances act by active forces being applied on the separated alveolar processes for growing them into desired anatomic position. The various appliances used for PSIO are discussed below and the technique of PSIO in different cleft types is summarized in Table 2.   [14,27].

Latham appliance
The Latham appliance also known as the Dentomaxillary Advancement Appliance (DMA) was developed to align the alveolar arch through rapid orthopedic correction and alignment of cleft segments was introduced by Dr Lantham and Georgiade [16,28]. Latham based his treatment concept on the facial growth hypothesis of Scott [29,30] with aim of the procedure 'to carry the prominence and ANB angle has been found for patients treated with this appliance [32]. However, other authors have concluded that this appliance did not affect dental arch relationships in preadolescent children [33]. The problem associated with procedure is that, besides neonatal maxillary orthopedics, infant periosteoplasty is always performed, although it is more limited with less undermining of periosteum on the maxilla.

Hotz appliance
In Europe, the treatment principles of McNeil for neonatal maxillary orthopaedics were greatly modified by grinding away the acrylic in specific areas to bring out necessary alignment, known as Hotz appliance (Zurich approach). According to Hotz and Gnoinski, the primary aim of presurgical orthopedics is not to facilitate surgery or to stimulate growth, as postulated by McNeil, but to take advantage of intrinsic developmental potentials. In Zurich approach lip operation is performed at the age of 6 months while palate repair is postponed until 5 years of age [34,35]. The appliance is made of hard acrylic or a combination of hard and soft acrylic: it passively covers the alveolar segments and extends slightly into the area of the cleft and the buccal sulci. This appliance assists with both bottle-feeding and to allow some breast-feeding in infants with CLP. Harmonization in the vertical and transverse positions of the cleft segments has been found with Hotz plate therapy [36].
Long-term effects of the Hotz plate and early lip adhesion have been studied by several researchers and it has confirmed that arch width and length of the anterior part of the maxilla improves better than other treatment options [37]. Similarly, the two-stage palatoplasty in combination with application of the Hotz' plate has good effects on the maxillary growth than one stage palatoplasty without Hotz plate [38].

Nasoalveolar molding
Earlier PSIO appliances were designed to correct the alveolar cleft only, despite the fact that the nasal deformity among these patients remains the greatest esthetic challenge. Grayson [21,39]  reduced oronasal fistulas and labial deformities, and a namely a 60% reduction in the need for secondary bone grafting [24].

Objectives of NAM in unilateral cleft lip and cleft palate (UCLP)
The main objective of NAM for UCLP is to reduce the severity of the original cleft deformity by reducing the width of the alveolar cleft segments and alignment of the base of the nose and lip segments [21]. Taping the lips together helps in correction of the inclined columella upright along the mid-sagittal plane. As the lower mid-face skeletal elements (alveolar ridge and lower maxilla) improve in relation to each other, the overlying soft tissue improves concurrently. The alar rim, which was initially stretched over a wide alveolar cleft deformity, shows some laxity that enables it to be elevated into a symmetrical and convex form. The nasal tip on the cleft side is overcorrected in its forward projection; this is achieved through the use of a nasal stent, an intra-oral acrylic plate, and surgical tapes [39][40][41][42][43][44].

Objectives of NAM in bilateral cleft lip and cleft palate cases
The main objective being the non-surgical elongation of the columella and also to center the pre-maxilla, along the mid-sagittal plane, retraction of the pre-maxilla in a slow and gentle process to achieve continuity with the posterior alveolar cleft segments.
Reduction in the width of the nasal tip, improved nasal tip projection and increase in the nasal alar base width [21,39,43].

Benefits of NAM
Proper alignment of lip, nose and alveolus is achieved, thereby enabling surgeons for better surgical repair of the cleft deformity and hence reduce post-surgical breakdown [42,43]. Approximation of alveolar process before surgery also enables surgeons to perform gingivo-periosteoplasty successfully. NAM provides stable change in nasal shape with less scar tissue and better lip and nasal form.
It also reduces the number of surgical revisions for excessive scar tissue, oro-nasal fistulas, nasal and labial deformities, due to proper columellar elongation and lengthening. With the alveolar segments in a better position and increased bony bridges across the clefts, the permanent teeth have a better chance of eruption in a good position with adequate periodontal support [39,40]. with inadequate activation [39][40][41][42][43][44].

Prevention of the complications associated with NAM Therapy
a) NAM therapy must be closely monitored and volunteered at timely basis with adequate application of mechanics and robust principles of the therapy must be followed. e) Parents must be thoroughly educated to continue the use of NAM appliance for their child until the therapy lasts. Feeding instructions must also be given accordingly.
f) Motivating the parents to visit the dentist on scheduled appointments and in timely manner is of utmost importance for a successful NAM therapy [39][40][41][42][43][44].

DynaCleft ® and Nasal Elevators
DynaCleft® is a premade nasal and alveolar molding device which can be used to successfully mold the upper lip, alveolus and nose prior to cleft lip repair. Traditional surgical adhesive tape (e.g. Silk tape, Steri-strips®) have been used in the past, unlike tape, DynaCleft® offers the benefit of being able to provide a constant approximation force with an elastic centre that allows it to conform to a baby's mouth better because of its ability to expand and contract. Additionally, the controlled force provided to the prolabium and premaxilla could improve surgical results and decrease the necessity of early lip adhesion surgery. As the DynaCleft® device is pre-made; there is no need to create custom-made devices for the molding process. Studies have shown that with the use of DynaCleft® with a nasal elevator has produced results similar to that of NAM therapy. However, unlike the NAM appliance, it does not require adjustments with growth of the infant. Nasal elevators have been found to improve the shape of the nose and alae, thereby reduce the need for primary surgery to the nose in patients with UCLP. Due to its elastomeric core and stretch property, DynaCleft® allows the infant to feed and cry without limitation.

Conclusion
Many orthodontists working on patients with CLP have shown great enthusiasm for PSIO to improve surgical outcomes with minimal intervention. Although different forms of PSIO appliances are available, it seems that NAM therapy has been especially popular in all over the world. Undoubtedly, every orthodontist or surgeon aims to use the best treatment modality for their patients.
Nevertheless, PSIO effects can be confounded by surgical type and timing of the primary repair, as is discussed in many studies. In such cases, one should be cautious when evaluating the particular outcomes for patients with CLP since it is difficult to differentiate the sole effect of an individual surgical or orthodontic intervention.