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At least 19 recordsLinked to original sources
PubMed2001

Repair of bilateral clefts of lip, alveolus and palate Part 1: A refined method for the lip-adhesion in bilateral cleft lip and palate patients.

The protruding premaxilla represents the most severe problem in the surgical closure of a bilateral cleft lip, alveolus and palate (BCLP). In principle there are two methods to overcome this obstacle: (1) preliminary lip adhesion and (2) presurgical repositioning with intraoral devices. According to the various degrees of premaxillary protrusion, sometimes adhesion alone is sufficient, if the surgical technique is unlikely to break down. In this paper a refined adhesion method is presented, withstanding traction to the wound margins and concomitantly enables lip and nose repairs in a single second operation. For patients with severe premaxillary protrusion, presurgical use of a Latham appliance achieves conditions for safe lip adhesion as above. Both treatment methods are outlined. Copyright 2001 European Association for Cranio-Maxillofacial Surgery.

Journal Article↗
PubMed1985

Strain differences between C57BL/6 and SWV mice in time of palate closure and induction of palatal slit and cleft palate.

Palatal slit, which occurs spontaneously in C57BL/6 (C57BL) mice, is increased in frequency among C57BL fetuses from dams treated with triamcinolone acetonide, but is not induced in SWV fetuses. On the other hand, C57BL is more resistant than SWV to cleft palate induction by triamcinolone. Using these C57BL and SWV mice, the relation of palate stage and chronological age was examined from 1 P.M. on day 14 to 9 A.M. on day 16 in untreated embryos, and the condition of the palate after triamcinolone treatment on day 12 was examined at 9 A.M. on day 16. In untreated embryos, horizontalization and fusion of the palatal shelves occurred earlier in C57BL than in SWV embryos, but fusion of the primary palate with the secondary palate occurred later. After triamcinolone treatment, the development of the palate was delayed in both C57BL and SWV embryos. These results suggest that the times of normal palate closure are related to the differences between C57BL and SWV mice in their susceptibilities to palatal slit and cleft palate induction and that triamcinolone produces palatal slit and cleft palate by delaying palate closure.

Abnormalities, Drug-Induced↗
PubMed1991

Palate morphology in children with cleft palate with palatalized articulation.

This study was designed to examine postoperatively morphological characteristics of the palate of children with cleft palate with palatalized articulation. Palate morphology was measured in children with good velopharyngeal closure function after surgery, who were classified in Hellman's Dental Age II A group with unilateral cleft lip and palate, and the groups of children with palatalized articulation (CP-P) and normal articulation (CP-N) were compared. The results showed that the group of children with palatalized articulation was characterized by small palatal volume. In particular, there was narrowing and shortening of the anterior palate, and the palate was shallow. It was surmised that morphology may be one cause of palatalized articulation. Accordingly, it is important that early tongue-clicking movements are encouraged in patients exhibiting narrow palate morphology.

Articulation Disorders↗
PubMed1996

Early palatal changes after initial palatal surgery in children with cleft lip and palate.

Early palatal growth and development after primary palatal closure was studied in children with different types of cleft lip and palate (CLP). Palatal dimensions were measured on dental casts taken at fixed ages, from 9 months to 4 years of age. The results showed that soft and hard palatal closure in one stage had a significant impeding influence on posterior sagittal palatal growth compared to closure of the soft palate only. Timing of surgery possibly had a small temporary restrictive effect on posterior transverse palatal growth and development. Type and severity of the oral cleft had a significant effect on transverse palatal development and anterior sagittal dimensions. Anterior arch width was reduced in children with a complete unilateral (U) CLP or bilateral (B) CLP. The palates of the latter children had consistently larger anterior arch depths. Compared to normal children, palates of cleft children changed anteriorly from wider at 9 months of age to narrower at 4 years of age. Arch depths were smaller in cleft children except for anterior arch depths in children with complete BCLP.

Age Factors↗
PubMed1994

The pattern of palatal rugae in submucous cleft palates and isolated cleft palates.

The early diagnosis of submucous cleft palate is important. In children too young to tolerate nasendoscopy and videofluoroscopy the diagnosis depends on the clinical history and intraoral examination. We have studied the pattern of the hard palate rugae to investigate their possible diagnostic significance. Maxillary dental casts were obtained from 16 patients with submucous cleft palate, 17 patients with isolated clefts of the secondary palate, and 10 non-cleft controls. The hard palate mucosa had a unique feature in 14 (87.5%) of the submucous cleft palates: one or more of the palate rugae curved towards the region of the bony notch in the posterior border of the hard palate. The 2 cases without this rugae pattern did not have a detectable bony notch. In 100% of the isolated cleft palate cases, one or more of the rugae curved towards the anterior end of the cleft. This feature was not seen in any of the non-cleft controls. We consider this rugae pattern to be an additional diagnostic feature of submucous cleft palate.

Child↗
PubMed2002

Cytophotometrical and immunohistochemical analysis of soft palate muscles of children with isolated cleft palate and combined cleft lip and palate.

Palatal muscle biopsies from the cleft margin of children were subjected to cytophotometrical and immunohistochemical analysis. Muscle fiber types were classified according to the enzyme activity of myofibrillic adenosine triphosphatase, glycerol-3-phosphate-dehydrogenase and succinate dehydrogenase assessed cytophotometrically. Fiber type-related immunoreactivity of nitric oxide synthase (NOS) isoforms I, II, III, as a physiological modulator of skeletal muscle function, was related to the oxidative and glycolytic activity of the muscle fibers. Fast oxidative glycolytic fibers with high oxidative activity showed strong NOS I immunoreactivity, whereas fast glycolytic fibers with high glycolytic activity were stronger immunolabelled for NOS III. NOS II expression was similar in all fiber types. No differences in NOS immunoreactivity were found between the two investigated forms of deformity. Additionally to the usual skeletal muscle fiber types, a slow tonic fiber type was for the first time identified in cleft palate muscles. Comparison of two forms of cleft palate, isolated cleft palate and combined cleft lip and palate has shown decreased enzyme activities in muscle fibers of palatal muscles from combined cleft lip and palate. Fast oxidative glycolytic fibers were mainly effected. Cytophotometrical and immunohistochemical analysis indicated a depressed performance of the cleft palatal muscles from combined cleft lip and palate as a stronger deformity compared with isolated cleft palate.

Adenosine Triphosphatases↗
PubMed1982

The developing ferret palate--a scanning electron microscope study: I. Primary palate and secondary palatal shelves.

Palatogenesis was studied in the ferret (Mustela putorius) from day 27 to day 29 of gestation. At day 27 the primary palate is present as a flattened shield area, and the two secondary palatal shelves are directed at 45 degrees to the horizontal plane, passing downward on the lateral sides of the tongue, which occupies the space between them. By day 28 the primary palate is bulging convexly in the oral cavity, and the secondary palatal shelves have elevated and are in contact in the midline. Finally, at day 29 the primary palate and nasal septum are in contact with the two secondary palatal shelves. During fusion of the secondary palatal shelves, no structures (leading edges or filopedia) associated with cell movement were apparent. It is suggested there are two stages of secondary palate formation in the ferret; an initial contacting of the secondary palatal shelves with the production of cell debris, and further midline movement of the shelves and cell migration out of the epithelial seam.

Animals↗
PubMed2003

[Bone regeneration on hard palate after palatal surgery on cleft palate and the relative factors].

OBJECTIVE: Attending to observe the bony healing on hard palate after palatal repair, and to discuss the factors affecting on it. METHODS: 52 patients with repaired cleft palate over 5 years postoperatively were examined, the CT scan of head was taken. The incidence of the bone regeneration among the patients examined was calculated, the position and quality of bone tissue were measured according to the CT images. After all, analysis was applied to evaluate the factors affecting on the bone tissue formation. RESULTS: Formation of bone bridge was found in the 37 cleft gaps out of 52 patients (71%), the ratio of the sex among the patients who had bone bridge was 1:1, there was no obvious difference between unilateral and bilateral cleft palate. Considering the operation age with the bone formation, the highest percentage of bone bridge formation fell into the group of 4-7 years old, and the most occurring region were in premolar and anterior part of molar area. CONCLUSION: There could be bony healing(regeneration bone tissue RBT) after palatal repair on cleft palate patients. The operation age could be an important affecting factor to RBT, but the sex and the clinical type of cleft palate make no difference on the bone tissue formation.

Age Factors↗
PubMed2000

A comparison of growth impairment and orthodontic results in adult patients with clefts of palate and unilateral clefts of lip, palate and alveolus.

OBJECTIVE: To evaluate and compare the long-term aesthetic and functional results of surgical and orthodontic treatment in patients with cleft palate and unilateral cleft lip, palate, and alveolus. DESIGN: 30 patients with unilateral cleft lip, palate, and alveolus and 30 patients with isolated cleft palate, mean age of 18.9 years, were evaluated by cephalometric and model analysis a mean of 1.5 years after orthodontic treatment. In each group the surgical treatment has been similar. RESULTS: Model analysis: The sum of every mesiodistal tooth diameter in the maxilla and in the mandible was recorded according to the Bolton analysis. Twenty patients with unilateral cleft lip, palate and alveolus had relatively large upper dental arches and nine had relatively large lower dental arches. Twenty-two patients with cleft palates had large upper dental arches and seven had large mandibular arches. Eleven patients with unilateral cleft lip, palate, and alveolus and 18 patients with cleft palate had a negative space supply (the sum of the mesiodistal tooth diameters compared with the sagittal length of the alveolar ridge) in the region of the lateral teeth. All patients had persistent transverse space deficits that were increased on the side of the cleft in patients with cleft lip, palate, and alveolus. These unilateral transversal space deficits were recorded in 22 patients with unilateral cleft lip, palate, and alveolus and in 8 patients with isolated cleft palate. Sagittal measurements were reduced in 26 patients with unilateral cleft lip, palate, and alveolus and in 23 patients with cleft palate alone. The alveolar midline of the maxilla and the mandible were displaced in 25 patients with unilateral cleft lip, palate, and alveolus and in 19 patients with isolated cleft palate. Lateral cephalometric analysis: The lateral cephalograms taken at the same time as the models showed a mean SNA of 76.8 degrees and a NL-NSL angle of 8.7 degrees, indications of a tendency towards maxillary retrognathia in patients with unilateral cleft lip, palate, and alveolus. Patients with cleft palate had a mean SNA of 79.6 degrees and NL-NSL angle of 8.1 degrees. The anterior facial vertical index was within normal limits in patients with cleft lip, palate, and alveolus (44% vs 56%). An anterior facial height index of 42% compared with 58% in patients with isolated cleft palate indicated a slight reduction in midface height with an increase in the lower face as a consequence. CONCLUSION: Orthodontic and surgical treatment can result in satisfactory results on model analysis. However, there is specific growth impairment of the maxilla 1.5 years after termination of orthodontic treatment and this influences the final cephalometric analysis, particularly in patients with cleft lip, palate, and alveolus.

Adolescent↗
PubMed2001

An in vitro mouse model of cleft palate: defining a critical intershelf distance necessary for palatal clefting.

It is unclear whether cleft palate formation is attributable to intrinsic biomolecular defects in the embryonic elevating palatal shelves or to an inability of the shelves to overcome a mechanical obstruction (such as the tongue in Pierre Robin sequence) to normal fusion. Regardless of the specific mechanism, presumably embryonic palatal shelves are ultimately unable to bridge a critical distance and remain unapproximated, resulting in a clefting defect at birth. We propose to use a palate organ culture system to determine the critical distance beyond which embryonic palatal shelves fail to fuse (i.e., the minimal critical intershelf distance). In doing so, we hope to establish an in vitro cleft palate model that could then be used to investigate the contributions of various signaling pathways to cleft formation and to study novel in utero treatment strategies. Palatal shelves from CD-1 mouse embryos were microdissected on day 13.5 of gestation (E13.5; term = 19.5 days), before fusion. Using a standardized microscope ocular grid, paired palatal shelves were placed on a filter insert at precisely graded distances ranging from 0 (in contact) to 1.9 mm (0, 0.095, 0.19, 0.26, 0.38, 0.48, 0.57, 0.76, 0.95, and 1.9 mm). A total of 68 paired palatal shelves were placed in serum-free organ culture for 96 hours (n = 68). Sample sizes of 10 were used for each intershelf distance up to and including 0.48 mm (n = 60). For intershelf distances of 0.57 mm and greater, two-paired palatal shelves were cultured (n = 8). All specimens were assessed grossly and histologically for palatal fusion. Palatal fusion occurred in our model only when intershelf distances were 0.38 mm or less. At 0.38 mm, eight of 10 palates appeared grossly adherent, whereas six of 10 demonstrated clear fusion histologically with resolution of the medial epithelial seam and continuity of the palatal mesenchyme. None of the 18 palates fused when placed at intershelf distances of 0.48 mm or greater. Using our selected intershelf distances as a guideline, we have established an approximate minimal critical intershelf distance (0.48 mm) at which we can reliably expect no palatal fusion. Culturing palatal shelves at intershelf distances of 0.48 mm or greater results in nonfusion or clefting in vitro. This model will allow us to study biomolecular characteristics of unfused or cleft palatal shelves in comparison with fused shelves. Furthermore, we plan to study the efficacy of grafting with exogenous embryonic mesenchyme or candidate factors to overcome clefting in vitro as a first step toward future in utero treatment strategies.

Animals↗
PubMed1999

A multicenter retrospective 3D study of serial complete unilateral cleft lip and palate and complete bilateral cleft lip and palate casts to evaluate treatment: part 1--the participating institutions and research aims.

OBJECTIVE: To compare the multicenter retrospective and prospective spatiotemporal (4D) serial analyses of complete unilateral (CUCLP) and complete bilateral (CBCLP) cleft lip and palate casts that had undergone different treatment procedures. The involved institutions are Miami Craniofacial Anomalies Foundation, South Florida Cleft Palate Clinic; University Hospital of Nijmegen Cleft Palate Center; Free University of Amsterdam Cleft Palate Center; Academic Hospital (Dijkzigt/Sophia) Rotterdam Cleft Palate Center; Center for Craniofacial Anomalies, University of Illinois College of Medicine; Cleft Palate Center, Sahlgrenska University Hospital, Göteborg, Sweden; and Children's Memorial Medical Center, Northwestern University Cleft Palate Institute. DESIGN: Using serial casts of the upper jaw and an electromechanical digitizer with special Cad-Cam software (CadKey), the occlusal relationships and morphometric palatal growth changes that occur under the influence of presurgical orthopedics and various surgical procedures will be studied. It is anticipated that 3D geometric data extracted from serial casts will identify the important geometric palatal parameters present before cleft surgical closure, which will supply objective criteria for establishing a scientific basis for improved surgical therapy. This research study will test three hypotheses: (1) Conservative (varying the timing of surgical cleft closure according to the size of the cleft space) lip and palatal surgery will permit "catch-up" palatal growth and normalize palatal growth and development. (2) The amount of mucoperiosteal tissue relative to the size of the cleft space is important in determining the timing of palatal surgery, as it influences the degree of scarring and ultimately the palate's adult size and form. (3) Presurgical orthopedics (the use of appliances soon after birth) can stimulate palatal growth beyond its normal growth potential. RESULTS: In a previous project and again after reviewing the data already collected during the first year of this study, it has been shown that incremental changes in size of palatal segments in CUCLP and CBCLP cases prior to surgery vary slightly. The CBCLP cases grow slightly faster than CUCLP cases before surgery, but growth of the CBCLP cases decreases in acceleration after surgery. Reasons for these differences will be determined when more cases are analyzed and subjected to biostatistical analysis.

Adolescent↗
PubMed1984

Sensitive stages and dose-response analyses of palatal slit and cleft palate in C57BL/6 mice treated with a glucocorticoid.

C57BL/6 mice were treated subcutaneously with triamcinolone acetonide in a single dose of 2.5-15.0 mg/kg once on days 6-15 of pregnancy (vaginal plug = day 0) and the palate of their fetuses was examined at term. The sensitive stages of palatal slit and cleft palate induction were studied and dose-response relations on days 9 and 12 of pregnancy were analyzed by the log-probit transformation method and compared. The test of significant increase in the frequencies of palatal slit and cleft palate showed that the sensitive period of palatal slit began earlier and ended later than that of cleft palate. On day 9 of pregnancy, the slope of the palatal slit response was similar to that of the cleft palate response, but the median effective dose of the former was lower than that of the latter. The slope of the palatal slit response was similar on days 9 and 12; however, the median effective dose was significantly greater on day 9. By contrast, the slope of the cleft palate response on day 12 was significantly different from that on day 9. The results of these dose-response analyses suggest that the underlying mechanism may be the same in palatal slit induction on days 9 and 12 and in cleft palate induction on day 9; the mechanism underlying the cleft palate response on day 12 is different from that of the other three responses, and there is more than one mechanism for cleft palate induced by triamcinolone.

Animals↗
PubMed2001

The palatal island flap for reconstruction of palatal and retromolar trigone defects revisited.

BACKGROUND: Although a host of local soft tissue flaps have been described for the reconstruction of postoperative palatal defects, tissue-borne palatal obturators remain the most common form of rehabilitation of these defects. The palatal island flap, first applied to the reconstruction of the retromolar trigone and palatal defects, was first described by Gullane and Arena in 1977. This single-staged mucoperiosteal flap offers a reliable source of regional vascularized soft tissue that obviates the need for prosthetic palatal rehabilitation. OBJECTIVE: To describe a series of 5 cases in which the palatal island flap was used as a primary palatal or retromolar reconstruction. METHODS: We have retrospectively reviewed 5 consecutive cases between March 1998 and August 1999 wherein palatal island flaps were used for the primary reconstruction of postablative palatal defects. Each case was reviewed for primary pathologic findings, postoperative wound complications, postoperative speech and swallowing, and donor site morbidity. Selection of this reconstructive technique was based on the size and location of the defect and the assessment by the surgeon that the arc of rotation and amount of residual palatal mucosa were appropriate. RESULTS: Six local palatal island flaps were performed on 5 patients who had not undergone irradiation (1 patient underwent bilateral flaps). The primary pathologic findings included T1 N0 squamous cell carcinoma, T4 N0 squamous cell carcinoma, T2 N0 low-grade mucoepidermoid carcinoma, pigmented neurofibroma, and T2 N0 low-grade clear cell carcinoma. All of the lesions were located on the hard or soft palate or the retromolar trigone, and the average defect size was 7.2 cm(2). All 5 patients began an oral diet between postoperative days 1 and 5 (mean, 2 days), and all patients were discharged home without postoperative donor site or recipient site complications between days 1 and 6 (mean, 3 days). Donor site reepithelialization was complete by 4 weeks in all 5 patients. CONCLUSIONS: The palatal island flap offers a reliable method of primary reconstruction for limited lesions of the retromolar trigone and hard and soft palate. The mucoperiosteal tissue associated with this flap is ideal for partitioning the oral and nasal cavities and obviates the need for prosthetic palatal obturation.

Aged↗
PubMed2003

Association between palatal morphogenesis and Pax9 expression pattern in CL/Fr embryos with clefting during palatal development.

The CL/Fr mouse strain develops cleft lip and palate (CLP) spontaneously. In this study, Pax9 mRNA expression was investigated in the palatal shelves during palatal morphogenesis to assess the correlation between secondary palatal morphogenesis and Pax9 expression of CL/Fr embryos with spontaneous cleft lip and palate. The expression of Pax9 mRNA was characterised using whole mount in situ hybridisation with a digoxygenin-labelled probe. In the control strain of C57BL/6 and CL/Fr normal embryos, Pax9 was expressed in the palate, especially along the medial edge (ME), on embryonic day 13.5 (E13.5) and E14.5 when the palatal shelves grew vertically down the side of the tongue and subsequently elevated to a horizontal position, and was down regulated on E15.5 when the palatal shelves met and began fusing. In the cleft embryo, Pax9 was expressed in the ME region but was not down regulated on E15.5. Furthermore, whole mount in situ hybridisation was performed after organ culture, using CL/Fr-N and CL/Fr-BCL palatal shelves dissected and approximated by pairs on E13.5. This showed that Pax9 was still expressed in the ME region in separated palatal shelves of CL/Fr-N and CL/Fr-BCL embryos, while Pax9 expression was down regulated in paired palatal shelves. These expression patterns of Pax9 in normal and cleft embryos during palatal fusion indicate that Pax9 expression is altered in spontaneous cleft lip and palate, and concludes that there is a direct correlation between Pax9 expression and palatal fusion.

Animals↗
PubMed1996

Developmental expression and CORT-regulation of TGF-beta and EGF receptor mRNA during mouse palatal morphogenesis: correlation between CORT-induced cleft palate and TGF-beta 2 mRNA expression.

Glucocorticoids (CORT) have been shown to induce cleft palate in mice. Although the pathogenetic pathway of CORT-induced cleft palate has been investigated for several decades, the molecular details remain to be elucidated. Since growth factors have been shown to regulate palate morphogenesis, and the expression of several growth factors or their receptors, e.g. TGF-beta, EGF receptor (EGF-R), are known to be modulated by CORT, we postulate that CORT modulation of growth factor (or receptor) gene expression is a key mechanism involved in CORT-induced cleft palate. To test this hypothesis, we analyzed the steady-state levels (Northern and RNase protection) and developmental expression (in situ hybridization) of four CORT-responsive genes--TGF-Beta 1, TGF- beta 2, TGF-beta 3, and EGF receptor (EGF-R)--in developing mouse palates in the presence or absence of exogenous CORT. Pregnant B10.A dams were injected on day 12 of gestation with CORT or sham-injected and embryonic palates were collected at 1, 2, and 3 days postinjection (E13-E15). During mouse palate development, significant increases in TGF-beta 1 and TGF-beta 3 mRNA levels, as well as significant decrease in TGF-beta 2 mRNA levels, are detected; no significant difference in EGF-R transcript level is observed with progressive development. In CORT-exposed palates, we demonstrate no significant differences in the direction or magnitude of change with time in TGF-beta 1, TGF-beta 3, and EGF-R mRNA levels compared to controls. However, CORT delays by 1 day the down-regulation of palatal TGF-beta 2 transcript normally seen on day 14 of gestation. TGF-beta 2 is known to inhibit cell proliferation. The level of TGF-beta 2 mRNA, the only isoform primarily expressed in the palatal mesenchyme, significantly decreases with progressive palatal development; this down-regulation of TGF-beta 2 expression is associated with increased mesenchymal cell proliferation and palatal shelf growth. CORT, at a critical stage of palatogenesis, induces a delay in the normal down-regulation of TGF-beta 2 gene expression. Given that CORT is known to inhibit mesenchymal cell proliferation and palatal shelf growth, we conclude that the CORT-induced delay in the normal down-regulation of TGF-beta 2 gene expression is probably key event in the pathogenesis of CORT-induced cleft palate.

Animals↗
PubMed1981

Cortisone-induced cleft palate in A/J mice: failure of palatal shelf contact.

Although cortisone treatment for induction of cleft palate in mice has been shown to delay the time of palatal shelf elevation, the effects of delayed elevation of shelf contact have not been critically evaluated in a cortisone-sensitive mouse strain. The objective of this study was to evaluated palatal development in cortisone-treated A/J mice in order to determine whether the shelves make contact upon elevation. Morphometric analysis of frozen sections revealed that cortisone-treated shelves were smaller than control shelves with apparent reductions in both the content of extracellular matrix and the number of cells. At a light microscopic level, thinning of medial epithelium in cortisone-treated palates appeared similar to that in untreated palates with spontaneous cleft lip and palate. Shelf elevation was delayed by approximately 12 hours and only half of the cortisone-treated palates achieved complete horizontal positioning of the shelves in all regions of the palate. Immediately after elevation, all control palates had extensive vertical contact along the complete length of the palate. In contrast, approximately 20% of the cortisone-treated fetuses had contact between the shelves in the middle palate region only, with the mean area of contact only 20% as large as in control fetuses. As result, the net shelf contact in all the cortisone-treated fetuses was only 4% of the potential contact shown in control fetuses. Therefore, failure of the palatal shelves to elevate and make extensive contact appeared to be the major factor contributing to cortisone-induced cleft palate in A/J mice.

Animals↗
PubMed2001

A comparison of dental and dentoalveolar changes between rapid palatal expansion and nickel-titanium palatal expansion appliances.

A tandem-loop nickel titanium temperature-activated palatal expansion appliance was developed that produces light, continuous pressure on the midpalatal suture and requires little patient cooperation or laboratory work. The purpose of this study was to compare the effectiveness of the nickel titanium palatal expansion appliance with that of a rapid palatal expansion appliance. The study sample comprised 25 patients who required palatal expansion as part of their orthodontic treatment. The sample was divided into 2 groups, with 13 patients in the nickel titanium group and 12 patients in the rapid palatal expansion group. Study models were taken before treatment and at the end of the retention period after expansion. Intermolar width, palatal width, palatal depth, alveolar tipping, molar tipping, and molar rotation were analyzed. In addition, occlusal radiographs were obtained before and 2 weeks after expansion to evaluate for sutural separation by the appliances. Results showed significant increases in midpalatal sutural separation, tipping of the alveolus, and tipping of the molars after expansion in both groups. However, greater midpalatal sutural separation was found in the rapid palatal expansion group and greater molar rotation was found in the nickel titanium group. Stepwise multiple regression analysis showed that alveolar tipping, palatal width change, and molar tipping are the best predictors of intermolar width change in the rapid palatal expansion group. Radiographic evidence of midpalatal sutural separation was less obvious in the nickel titanium group. These results suggest that both the nickel titanium and the rapid palatal expansion appliances are capable of expanding the maxillary dentition and alveolar process and are equally capable of correcting posterior crossbites. In the current study, the rapid palatal expander widened the palate more reliably, whereas the nickel titanium expander tipped the molars buccally to a greater extent and caused more distal molar rotation. The clinician's choice of expander will depend on his or her initial diagnosis and treatment goals.

Alveolar Process↗