Scar tissue distribution on palates and its relation to maxillary dental arch form

Sagittal Growth Restriction of the Midface Following Isolated Cleft Lip Repair: A Systematic Review and Meta-Analysis

Midface hypoplasia (MFH) is a long-term sequela of cleft lip and palate repair, and is poorly understood. No study has examined the aggregate data on sagittal growth restriction of the midface following repair of the lip, but not palate, in these patients.

A systematic review of 3780 articles was performed. Twenty-four studies met inclusion criteria and 11 reported cephalometric measurements amenable to meta-analysis. Patients with Veau class I-III palatal clefts were included so long as they had undergone only lip repair. Groups were compared against both noncleft and unrepaired controls.

Cephalometrics were reported for 326 patients (31.3% female). Noncleft controls had an average SNA angle of 81.25° ± 3.12°. The only patients demonstrating hypoplastic SNA angles were those with unilateral CLP with isolated lip repair (77.4° ± 4.22°). Patients with repaired CL had SNA angles similar to noncleft controls (81.4° ± 4.02°). Patients with unrepaired CLP and CL tended toward more protruding maxillae, with SNA angles of 83.3° ± 4.04° and 87.9° ± 3.11°, respectively. Notably, when comparing SNA angles between groups, patients with CLP with isolated lip repair had significantly more hypoplastic angles compared to those with repaired CL (P < .0001). Patients with CLP with isolated lip repair were also more hypoplastic than noncleft controls (P < .0001). In contrast, there was no significant difference between the SNA of patients with repaired CL and controls (P = .648).

We found that cleft lip repair only appeared to contribute to MFH in the setting of concurrent cleft palate pathology, suggesting that scarring from lip repair itself is unlikely to be the predominant driver of MFH development. However, studies generally suffered from inadequate reporting of timing, technique, follow-up time, and cleft severity.

F-quad helix for simultaneous maxillary expansion and tooth alignment in patients with unilateral cleft lip and/or palate

Illustrating F-quad helix with extension arms that simultaneously expand maxillary arch and rotate its central incisor adjacent to the alveolar cleft while aligning palatally ectopic canines. Incisor rotation occurred before alveolar grafting, while canine traction was performed after alveolar grafting. The construction of this appliance is shown in detail.

A Preliminary Study of Interdisciplinary Approach with a Single-Stage Surgery in Children with Cleft Lip and Palate

A two-stage surgical procedure involving labioplasty and palatoplasty is a common surgical modality performed in children with cleft lip and palate. Additionally, an alveolar cleft bone graft is performed prior to the eruption of the canine teeth. These three surgeries impose the burden of general anesthesia separately for each procedure, and the formation of scar tissue from the procedure inhibits maxillary growth. We adopted a single-stage surgical procedure to overcome these drawbacks. To date, there have been no reports comparing the treatment outcomes of alveolar morphology and maxillary growth and development in children who underwent single-stage surgery with those who underwent two-stage surgery using plaster casts and cephalograms. Twenty children aged 5–7 years were equally divided into two groups based on whether they had undergone a two- or single-stage procedure. Cephalometric analysis and analysis of dentition models were conducted. The results showed that the single-stage surgery exhibited significant differences in the sella-nasion angle, point A to McNamara line, maxillary length, mandibular body length, and posterior arch width and length compared with the two-stage surgery. Therefore, it was suggested that the single-stage surgery had a favorable effect on maxillary growth compared with the two-stage surgery.

Engineered mucoperiosteal scaffold for cleft palate regeneration towards the non-immunogenic transplantation

Cleft lip and palate (CL/P) is the most prevalent craniofacial birth defect in humans. None of the surgical procedures currently used for CL/P repair lead to definitive correction of hard palate bone interruption. Advances in tissue engineering and regenerative medicine aim to develop new strategies to restore palatal bone interruption by using tissue or organ-decellularized bioscaffolds seeded with host cells. Aim of this study was to set up a new natural scaffold deriving from a decellularized porcine mucoperiosteum, engineered by an innovative micro-perforation procedure based on Quantum Molecular Resonance (QMR) and then subjected to in vitro recellularization with human bone marrow-derived mesenchymal stem cells (hBM-MSCs). Our results demonstrated the efficiency of decellularization treatment gaining a natural, non-immunogenic scaffold with preserved collagen microenvironment that displays a favorable support to hMSC engraftment, spreading and differentiation. Ultrastructural analysis showed that the micro-perforation procedure preserved the collagen mesh, increasing the osteoinductive potential for mesenchymal precursor cells. In conclusion, we developed a novel tissue engineering protocol to obtain a non-immunogenic mucoperiosteal scaffold suitable for allogenic transplantation and CL/P repair. The innovative micro-perforation procedure improving hMSC osteogenic differentiation potentially impacts for enhanced palatal bone regeneration leading to future clinical applications in humans.

A Preliminary Study of Anatomical Changes Following the Use of a Pedicled Buccal Fat Pad Flap During Primary Palatoplasty

OBJECTIVE

The purpose of this study was to examine the surgical impact of the pedicled buccal fat pad (BFP) flap on the levator veli palatini (LVP) muscle and surrounding velopharyngeal (VP) anatomy following primary palatoplasty using magnetic resonance imaging (MRI).

DESIGN

Observational, prospective.

SETTING

MRI studies were completed at 3 different facilities. All participants with BFP flap were operated on by the same surgeon.

PARTICIPANTS

Five pediatric participants with cleft palate with or without cleft lip (CP±L) who underwent primary palatoplasty with BFP flap placement. Comparison groups consisted of 10 participants: 5 with CP±L who did not receive the BFP flap and 5 healthy controls.

INTERVENTIONS

All participants underwent nonsedated MRI 2 to 5 years postoperatively.

MAIN OUTCOMES AND MEASURES

Anatomical measures of the velopharynx and LVP among the 3 participant groups.

RESULTS

Median values were significantly different among groups for velar length (P = .042), effective velar length (P = .048), effective VP ratio (P = .046), LVP length (P = .021), extravelar LVP length (P = .009), and LVP origin-origin distance (P = .030). Post hoc analysis revealed a statistically significant difference between the BFP and traditional repair groups for effective VP ratio (P = .040), extravelar LVP length (P = .033), and LVP length (P = .022).

CONCLUSIONS

This study provides preliminary support that the BFP flap creates a longer velum, with increased distance between the posterior hard palate and the LVP, and a larger effective VP ratio compared to traditional surgical techniques. Future research is needed to determine whether this procedure provides a more favorable mechanism for VP closure.

Changes in maxillary dental arch morphology after implant treatment in the alveolar cleft region

Background

Few reports have examined dental arch morphology (DAM) after dental implant placement in cleft patients and its actual state is unclear.

Objective

To analyze the presence of changes in DAM and influencing factors in cleft lip and/or palate (CLP) patients who receive implant treatment in the alveolar cleft region.

Methods

Subjects comprised 20 CLP patients in whom maxillary dental arch width (DAW) was evaluated before and after implant treatment based on computed tomography data. First, widths between the canines (W3), between the first premolars (W4), between the second premolars (W5), and between the first molars (W6) were measured before and after surgery. Changes in distance were analyzed using the Wilcoxon signed‐rank test, revealing a significant increase in W6. Analysis of Co‐Variance was performed with the difference in W6 after implant treatment as the response variable, and the following six items as explanatory variables: sex; cleft type; age at alveolar bone graft; time to implantation after bone grafting; number of implants; and time after completion of the observation period.

Results

The reduction in W6 was larger in the order of complete bilateral CLP, complete unilateral CLP, and unilateral cleft lip and alveolus, and the change decreased with an increasing number of implants.

Conclusions

Implant treatment of the alveolar cleft region may result in a slight reduction in width of the dental arch after treatment completion.

Early or delayed palatoplasty in complete unilateral cleft lip and palate patients? A systematic review of the effects on maxillary growth

The aim of this study was to review the effects of early and late hard palate repair on maxillary growth. PubMed, Scopus, Web of Science, LILACS, Cochrane Library CENTRAL databases, OpenGrey, Google Scholar, and Clinical Trials were searched using a PICO strategy, with terms related to unilateral cleft lip and palate (UCLP) and timing of repair. Methodological quality evaluation was carried out using the Fowkes and Fulton guidelines, and quality (or certainty) of evidence and strength of recommendations were evaluated using GRADE (grading of recommendations, assessment, development and evaluation). Five retrospective and non-randomized studies were included in the study. Folkes and Fulton assessment showed a high risk of bias in all articles and very low levels of certainty (GRADE). The results showed conflicting findings for comparisons of the effects of timing of repair of hard palate in UCLP. Two studies presented better maxillary growth in a group operated on later (18 months after birth), two presented no differences between the results, and another presented better results in the group operated on earlier than 18 months of age. At this point, it cannot be proven or refuted that postponing hard palate surgery brings benefits for maxillary growth. Studies included in this review did not show similar conclusions. Randomized clinical trials present some ethical issues that make them difficult to perform.

Three-Year Follow-Up of a Patient With Unilateral Cleft Lip and Palate Treated With Maxillary Protraction and Alveolar Bone Grafting: An Approach Exploring the Potential Power of Growth

Clinically, patients with operated unilateral cleft lip and palate always present with a concave profile, depressed midface, maxillary hypoplasia, narrow upper dental arch, and class III malocclusion. In this clinical report, the authors describe the successful orthodontic treatment of a patient with unilateral cleft lip and palate. A boy, 7 years 11 months of age, with a history of unilateral cleft lip and cleft palate presented with a Class I malocclusion on Skeletal Class III base. A satisfactory occlusion and a favorable lateral profile were achieved after maxillary protraction (face mask) combined with fixed appliance treatment, including alveolar bone grafting surgery. An acceptable occlusion and facial proportion were maintained after a 3-year retention period. These results suggest orthodontic treatment with growth interference is an effective option for a patient with cleft lip and palate.

Orthodontic-Surgical Approach for Treating Skeletal Class III Malocclusion With Severe Maxillary Deficiency in Isolated Cleft Palate

Orthodontic treatment in patients with orofacial cleft such as cleft lip and palate or isolated cleft palate is challenging, especially when the patients exhibit severe maxillary growth retardation. To correct this deficiency, maxillary expansion and protraction can be performed in the first phase of orthodontic treatment. However, in some cases, the malocclusion cannot be corrected by these procedures, and thus, skeletal discrepancy remains when the patients are adolescents. These remaining problems occasionally require various orthognathic treatments according to the degree of the discrepancy. Here, we describe one case of a female with isolated cleft palate and hand malformation who exhibited severe maxillary deficiency until her adolescence and was treated with multiple orthognathic surgeries, including surgically assisted maxillary expansion (surgically assisted rapid palatal expansion), LeFort I osteotomy, and bilateral sagittal split osteotomy in order to correct severe skeletal discrepancy and malocclusion. The treatment resulted in balanced facial appearance and mutually protected occlusion with good stability. The purpose of this case report is to show the orthodontic treatment outcome of 1 patient who exhibited isolated cleft palate and subsequent severe skeletal deformities and malocclusion which was treated by an orthodontic-surgical approach.

Treatment Outcome of Bangladeshi UCLP Patients Based on Both Phenotype and Postnatal Treatment Factors using Modified Huddart Bodenham (mHB) Index

OBJECTIVE

To evaluate the dental arch relationship (DAR) of nonsyndromic unilateral cleft lip and palate (UCLP) and to explore the various phenotype and postnatal treatment factors that are responsible for poor DAR.

DESIGN

Retrospective study.

SETTING

School of Dental Science, Universiti Sains Malaysia.

SUBJECTS

Eighty-four Bangladeshi children with nonsyndromic UCLP who received cheiloplasty and palatoplasty.

MAIN OUTCOME MEASURES

Dental models were taken at 5 to 12 years of age (man: 7.69), and dental arch relationships were assessed using modified Huddart/Bodenham index (mHB) by two raters. Kappa statistics was used to evaluate the intra- and interexaminer agreements, chi-square was used to assess the associations, and logistic regression analysis was used to explore the responsible factors that affect DAR.

RESULTS

The total mHB score (mean [SD]) was -8.261 (7.115). Intra- and interagreement was very good. Using crude and stepwise backward regression analysis, significant association was found between positive history of class III (P = .025, P = .030, respectively) and unfavorable DAR. Complete UCLP (P = .003) was also significantly correlated with unfavorable DAR.

CONCLUSION

This multivariate study suggested complete type of UCLP and positive history of class III had a significantly unfavorable effect on the DAR.

Measurement of Distraction Force in Cleft Lip and Palate Patients During Le Fort I Maxillary Advancement With Rigid External Distraction

OBJECTIVE

Maxillary distraction osteogenesis (DO) is a mainstream surgical technique for patients who have severe maxillary hypoplasia associated with craniofacial syndromes and cleft-related deformities. However, limited information about the biomechanical aspects of maxillary DO is available limiting broad utilization and improvements to the procedure. The objective of this study was to analyze force levels during the active distraction process and to investigate the relationship between distraction force and maxillary movement during Le Fort I maxillary DO using a rigid external distraction (RED) system.

PATIENTS

Microtension gauges were integrated into the distraction wires on each side of the RED system. Six patients with cleft lip and palate aged 12.8 to 23.5 years underwent strain gauge measurements during maxillary advancement with DO using an RED system. Lateral cephalograms were taken to measure maxillary horizontal, vertical, and linear movements after DO.

RESULTS

The average linear maxillary movement was 11.2 mm (range 8.5-15.9 mm). The applied forces ranged from 13.4 to 26.8 N. The distance of maxillary movement was proportional to the distraction force.

CONCLUSIONS

The measurement of distraction forces during DO provides important information with which to establish appropriate protocols. Patients requiring more advancement may require more distraction force. However, other factors such as scarring, patient anatomy, surgical freedom of the osteotomized maxilla, and the like, may affect the required force during DO with the RED system.

Variations in Velopharyngeal Structure in Adults With Repaired Cleft Palate

OBJECTIVE

The purpose of this study was to examine differences in velopharyngeal structures between adults with repaired cleft palate and normal resonance and adults without cleft palate.

DESIGN

Thirty-six English-speaking adults, including 6 adults (2 males and 4 females) with repaired cleft palate (M = 32.5 years of age, SD = 17.4 years) and 30 adults (15 males and 15 females) without cleft palate (M = 23.3 years of age, SD = 4.1 years), participated in the study. Fourteen velopharyngeal measures were obtained on magnetic resonance images and compared between groups (cleft and noncleft).

RESULTS

After adjusting for body size and sex effects, there was a statistically significant difference between groups for 10 out of the 14 velopharyngeal measures. Compared to those without cleft palate, participants with repaired cleft palate had a significantly shorter hard palate height and length, shorter levator muscle length, shorter intravelar segment, more acute levator angles of origin, shorter and thinner velum, and greater pharyngeal depth.

CONCLUSION

Although significant differences were evident in the cleft palate group, individuals displayed normal resonance. These findings suggest that a wide variability in velopharyngeal anatomy can occur in the presence of normal resonance, particularly for those with repaired cleft palate. Future research is needed to understand how anatomic variability impacts function, such as during speech.

Anthropometric Analysis of the Velopharynx and Related Craniometric Dimensions in Three Adult Populations Using MRI

OBJECTIVE

The purpose of this study is to examine effects of sex, race, and craniometry among three distinct racial groups of adults with normal velopharyngeal anatomy and to determine whether craniofacial structures could be used to predict velopharyngeal structures.

METHODS

A total of 88 adults across three racial groups including white, black, and Asian (Japanese) participated. Magnetic resonance images were obtained using a high-resolution, three-dimensional anatomical scan. Measurements were obtained on the levator veli palatini muscle, velum, and craniofacial structures.

RESULTS

Head circumference was used as a covariate to control the effect of overall cranial size on the analyses. Palate height, linear cranial base, and face height and width vary based on sex, with men demonstrating larger values compared with women. Linear base values, cranial base angle, and face width vary significantly based on race, with Japanese subjects showing the smallest anterior to posterior measures and larger face-width values. Levator muscle measures, excluding angle measures, vary significantly (P < .0001) based on sex. There was no statistically significant difference (P > .05) among racial groups in the levator muscle measures. Velar length and thickness varied significantly based on race and sex.

CONCLUSIONS

This is the first study to examine the interaction of race and sex on levator muscle morphology. In spite of the differences in velar dimensions, no significant differences were found in muscle size, specifically the levator veli palatini, which is contained within the velum.

Vertical maxillary growth after two different surgical protocols in unilateral cleft lip and palate patients

Objective : The aim of the present study was to compare vertical maxillofacial growth in patients born with unilateral cleft lip and palate (UCLP) who were treated using two different surgical protocols. Design : A retrospective cohort study. Subjects : We studied 92 patients with complete UCLP (61 male and 31 female) treated at Sahlgrenska University Hospital in Gothenburg, Sweden: 46 consecutive patients born between 1965 and 1974 who underwent surgical treatment according to the Wardill-Kilner (W-K) protocol and 46 consecutive patients born between 1982 and 1989 who underwent surgical treatment according to the Gothenburg delayed hard palate closure (DHPC) protocol. Methods : We analyzed lateral cephalograms obtained at 10 years of age. Results : Patients treated according to the Gothenburg DHPC protocol had significantly greater anterior upper facial height, anterior maxillary height, overbite, and inclination of the maxilla than those treated with the W-K protocol. Both techniques led to similar posterior upper facial height. Conclusion : The Gothenburg DHPC protocol in patients with complete UCLP results in more normal anterior maxillary vertical growth and overbite and therefore increased maxillary inclination at 10 years of age.

Congenital and postnatal factors inducing malocclusions in Japanese unilateral cleft lip and palate patients-determination using logistic regression analysis

Objective : To assess the congenital and postnatal factors that affect degree of malocclusion in patients with unilateral cleft lip and palate using multivariate statistical analysis. Design : Retrospective study. Patients : All information on 135 subjects with unilateral cleft lip and palate was obtained from an oral examination and radiograph at the initial examination at an orthodontic clinic and from surgical records. Plaster models were taken before orthodontic treatment. The ages of the subjects ranged from 5 to 8 years with a mean age of 6.9 years. All primary surgeries for the patients were performed at a university hospital. Main Outcome Measures : The GOSLON Yardstick was used to assess the dental arch relationships (degree of malocclusion) in patients. Family history of Class III, degree of cleft, and congenitally missing upper lateral incisor on the cleft side were chosen as congenital factors inducing malocclusion. Presurgical orthopedic treatment, cheiloplasty, and palatoplasty were chosen as postnatal factors. Associations between various factors and dental arch relationships were assessed using logistic regression analysis. Results : According to adjusted odds ratios, family history of Class III is associated with a significantly worse dental arch relationship. Palatoplasty using push-back alone correlated to a dental arch relationship that was significantly worse than palatoplasty using push-back with a buccal flap. Conclusions : Multivariate analysis shows evidence that a positive family history of Class III and palatoplasty using push-back alone are associated with worse malocclusion of unilateral cleft lip and palate patients.

Changes in gingival blood flow during orthodontic treatment

The aim of the study was to investigate the changes in gingival blood flow due to orthodontic forces. Eleven volunteers, with the maxillary canine in an ectopic position were tested. A Laser Doppler Flowmeter (LDF) with a gingival probe was used, registering both the blood flow and temperature of the gingivae. After baseline measurement, a fixed orthodontic appliance was bonded. Measurements were repeated monthly, after activation of the appliance. The study lasted 6 months. The baseline value was 338.7 ± 201.56 P.U. [Perfusion Unit (mean ± S.D.)] which decreased to 218.9 ± 74.83 P.U. (p < 0.05) after two months and the final value of 363.9 ± 194.86 P.U was not significantly different from that initially (p > 0.5). The results showed that application of a force of 75 g resulted in a decrease in gingival blood flow up to 50%, but this returned to previous values after a few months. The study supports this measurement technique as a useful tool for monitoring gingival blood flow in long-term studies as well.

Effects of different types of palatal lateral excisions on growth and development of maxilla and dental arch

OBJECTIVE

This study aimed to explore the effects of different types of palatal lateral excisions on the growth and development of the maxilla and dental arch, and to investigate the underlying mechanisms.

METHODS

A total of 112 3-week-old Sprague-Dawley (SD) male rats were randomly divided into a control and 3 experimental groups: the mucoperiosteal denudation group, the mucosal flap excision group, and the periosteum excision group. In the experimental groups, bilateral mucoperiosteal, mucosal flap and periosteum were excised respectively in the lateral one half of the palate. Four rats in each group were randomly chosen for sacrifice every two weeks. The maxilla was dissected following the excision. The widths of the maxilla and dental arch were measured and the histological phenomena were investigated at different phases. At the same time, 12 animals in each group were sequentially injected with calcein every two weeks. Three animals in each group, whose fluorescent labeling was used, were sacrificed for investigating bone formation at Week 8 following injection.

RESULTS

(1) Each experimental group presented the constriction of the maxilla and dental arch. The upper first molars in the experimental groups inclined medially. The mucoperiosteal denudation group showed the largest degree of effect followed by the periosteum excision group. The indices of the mucosal flap excision group, which retained the structures of the periosteum layer, had the most approximate values to the control group; (2) Different histological changes among the experimental groups were detected. The fibers penetrated into the palatal bone as Sharpey's fibers in the mucoperiosteal denudation group. The pattern of bone deposition was the bundle type. Sharpey's fibers were not found in the mucosal flap and periosteum excision groups and the depositions of palatal bone were the lamellar type as those in the control group; (3) The rates of bone deposition in the experimental groups decreased compared with the control group. The rates in different phases were the most approximate values to those of the control group in the mucosal flap excision group, which has the same structure of periosteum as the control group.

CONCLUSION

There were different effects on the growth and development of the maxilla and dental arch in different types of palatal lateral excisions. Periosteum is important for bone formation and deposition pattern. The prevention of Sharpey's fibers forming and attaching to the palatine can effectively avert the following malformation.

Collagen scaffolds implanted in the palatal mucosa

Scar formation after repair of the cleft palate leads to growth impairment of the upper jaw and midface. The implantation of a suitable scaffold during surgery may reduce this adverse effect. However, little is known about tissue reactions to scaffolds implanted in the oral cavity. Our goal was to analyze the tissue reactions to cross-linked type I collagen scaffolds after submucoperiosteal implantation in the palate of rats. Collagen type I scaffolds were implanted in the palate of 25 male Wistar rats. Groups of 5 rats were killed consecutively after 1, 2, 4, 8, and 16 weeks and were processed for histologic and immunohistochemical analyses. After 1 and 2 weeks, 3 rats from the sham group were also killed. On hematoxylin and eosin-stained sections, the cell density and the number of giant cells were determined. Blood vessels, inflammation, and the presence of myofibroblasts were detected by immunohistochemistry. An influx of inflammatory cells started after 1 week but had completely subsided after 8 weeks. Myofibroblasts were observed within the scaffolds only in the first 2 weeks. Angiogenesis already started after 1 week and showed a peak after 4 weeks, slowly declining afterward. The scaffolds were gradually integrated within the host tissue and only elicited a mild and transient inflammatory response. The scaffolds were biocompatible and seemed to be promising for future applications in cleft palate surgery.

In vitro engineering of a palatal mucosa equivalent with acellular porcine dermal matrix

The objective of this study was to develop a palatal mucosa equivalent composed of multilayered oral keratinocytes grown on the acellular porcine dermal matrix. Acellular porcine dermal matrix was prepared through a series of procedures and assessed by histological, immunohistochemical, and scanning electron microscopy examination. The palatal mucosa equivalent was fabricated by seeding oral keratinocytes, which cultured from human palate mucosa, onto the acellular dermal matrix. After 4 days submerged in medium, this composite was raised to the air-liquid interface for another 7 or 14 days of cultivation. The results demonstrated the processed porcine dermal matrix was totally cell-free. The resultant palatal mucosa equivalent showed a multilayered oral epithelium that had been formed, and the number of cell layers was correlated with the culture period at the air-liquid interface. Oral keratinocytes infiltrated into the empty hair follicles of the acellular porcine dermal matrix and formed an anchor-like structure, which exhibited resemblance to the rete ridges of the native palate mucosa. Immunohistochemical staining for CK10/13, CK19, Ki-67 nuclear antigen, and Heparan sulphate indicated the cultured palatal mucosa equivalent shared the same characteristics with that of the native palate mucosa. In conclusion, our fabricated palatal mucosa equivalent exhibited the characteristics of the native counterpart, and this equivalent might be useful for recovery of the wounds in the palate secondary to palatoplasty.

Relapse Tendency in Maxillary Arch Width in Unilateral Cleft Lip and Palate Patients with Different Maxillary Arch Forms

Objective:

The aim of this study was to investigate the relapse tendency in the maxillary dental arch widths in unilateral cleft lip and palate patients with different types of maxillary arch form.

Subjects:

Thirty-two unilateral cleft lip and palate patients treated by one-stage surgical palatal closure were included. The subjects were divided into three groups according to the types of the maxillary arch forms: group A, symmetrical arch form; group B, collapse of minor segment; group C, collapse of both segments.

Methods:

Using dental casts obtained at three different times, relapse in the intercanine, interpremolar, and intermolar widths in each group was assessed and differences between groups were investigated.

Results:

Patients in group A showed stable results in all measurements. Patients in group B showed posttreatment relapse in the intercanine width only, whereas patients in group C demonstrated significant posttreatment relapses in the interpremolar and intermolar widths. Comparison between groups showed more significant relapse in the interpremolar and intermolar widths of group C than in those of group B.

Conclusion:

The types of the maxillary arch forms in unilateral cleft lip and palate patients might play a stronger role in the stability of the maxillary dental arch widths after orthodontic treatment in patients with collapse of both segments and a severe degree of maxillary narrowness.

Effects of Basic Fibroblast Growth Factor Administration on Vascular Changes in Wound Healing of Rat Palates

Objective:

The purpose of this study was to investigate the vascular changes induced by mucoperiosteal denudation of rat palate and to elucidate the effects of basic fibroblast growth factor (bFGF) administration on the palatal vascular network in wound healing.

Methods:

A total of 117 male Wistar rats were used for the study on their 20th postnatal day. The animals were divided into three groups: a scar formation group, a basic fibroblast growth factor group, and a control group. The scar formation and basic fibroblast growth factor groups had lateral mucoperiosteum excised from the palate. In the basic fibroblast growth factor group, a solution of basic fibroblast growth factor was injected into the operated area 1 week after excision. At 6, 8, and 10 weeks postoperatively, palatal vascular changes were investigated by immunohistochemical staining and corrosion cast techniques.

Results:

Throughout the experimental period, there were significantly fewer vessels in the scar formation group than in the control and basic fibroblast growth factor groups. In the basic fibroblast growth factor group, the elongation of new vessels and capillary proliferation proceeded, and after 10 weeks a highly organized vascular network was established. The scar formation group showed few Volkmann's canals that were shrunken or closed, whereas the basic fibroblast growth factor group evidenced Volkmann's canals with arterioles or venules, as seen in the control.

Conclusions:

The results suggested that injection of basic fibroblast growth factor into palatal wounds improves the vascular supply to the operated mucosa and underlying bone during and after palatal wound healing, which may contribute to tissue remodeling of the palate during growth.

Role of secreted frizzled-related protein 1 (SFRP1) in wound healing

Wound healing is a complex cascade of events, which diminishes the size of the wound and reestablishes tissue integrity. Secreted frizzled-related protein 1 (SFRP1) contributes to the inhibition of apoptosis in fibroblast populations. We investigated the role of SFRP1 in a mouse wound-healing model; 2.0-mm excisional wounds were created in the scalp and hard palate. Healing responses were measured by histomorphometric analysis, apoptosis assay, and immunohistochemistry. Dermal wounds did not harbor SFRP1, but healed faster than palatal wounds which expressed significant levels of SFRP1. Antibody experiments aimed at blocking SFRP1 in palatal wounds resulted in promotion of wound closure, enhancement of new tissue formation, decrease of inflammatory cell infiltrate, and increase of apoptotic fibroblasts. Analysis of the present data suggests that SFRP1 may be partly responsible for the poorer healing performance of the palatal wounds compared with dermal wounds. Blocking SFRP1 results in improvement of palatal healing outcomes.

Bone regeneration in the hard palate after cleft palate surgery

BACKGROUND

The purpose of this study was to observe bony healing in the hard palate after cleft palate repair and to discuss the factors affecting it.

METHODS

Fifty-two patients with repaired cleft palate were examined at least 1 year postoperatively by means of computed tomographic scanning. The incidence of bone regeneration automatically after repair was calculated, and the region of bone formation and the quality of bone tissue were measured according to the scanned image.

RESULTS

The formation of a bone bridge was found in 37 of 52 patients (71 percent). The length of regenerated bone tissue (in the anteroposterior direction) ranged from 2 to 20 mm, with an average length of 8.3 mm. The male-to-female ratio of the patients who had a bone bridge was 1:1. There was no obvious difference between the two different cleft types. Considering the relationship of age at operation and bone formation, the most popular age at which bone bridging occurred was 4 to 7 years, and the location in the hard palate with the highest percentage of bone formation was the area between the premolar and anterior part of the molar.

CONCLUSIONS

Regenerated bone tissue can occur after palatal repair in cleft palate patients. The age at operation could be an important factor affecting regeneration of bone tissue. The authors were not able to find a significant effect of sex or clinical type of cleft palate based on the sample size in this study.

Surgical Technique for the Correction of Postpalatoplasty Fistulae of the Hard Palate

Postpalatoplasty fistulas of the hard palate remain challenging. The reported recurrence rate after surgical correction ranges between 33 and 37 percent. The authors describe a surgical technique for the correction of postpalatoplasty fistulas by total elevation of the palatal gingivoperiosteum starting at the dental sulcus, excision of the fistula, and watertight separate closure of the nasal and palatal mucosa by means of the transoral approach. This technique has the advantages of providing adequate exposure for closure of the nasal mucosal gap and allowing closure of the palatal defect under minimal tension. Placement of interdental sutures leaves no raw bone surfaces exposed. The authors have used this technique on 60 consecutive patients with fistulas of the primary and secondary hard palate between 1998 and 2003. Their overall success rate of fistula closure was 90 percent. The success rate for previously unoperated postpalatoplasty fistulas was 96.9 percent. All of the failures occurred in patients who had bilateral cleft lip and palate. No complications of tooth loss or gingival recession were observed. A detailed description of the technique with illustrations is provided.

Unilateral advancement of the maxillary minor segment by distraction osteogenesis in patients with repaired unilateral cleft lip and palate: report of two cases

OBJECTIVE

Collapse of the maxillary minor segment with lateral crossbite is a common feature in patients with repaired unilateral cleft lip/palate because of maxillary alveolar bony defect and palatal scar tissue. Distraction osteogenesis (DOG) is an effective technique of lengthening and augmentation for bone and gingiva. This case report describes the effects of unilateral advancement of the maxillary minor segment by DOG in two patients with the repaired unilateral cleft lip/palate.

Effects of locally injected interferon-β on palatal mucoperiosteal wound healing

BACKGROUND

Wound contraction and scar formation in the palatal mucoperiosteum after cleft palate surgery impair maxillary growth. The aim of this study was to determine the effects of IFN-beta on palatal mucoperiosteal wound healing in growing rats.

METHODS

Standardized wounds were made in the palatal mucoperiosteum of young rats. Either IFN-beta or vehicle were injected at the wound site between 4 and 29 days after wounding. The results were compared with control wounds. Tissue samples were collected at 8, 15, 30, and 60 days PW for biochemical and microscopic analysis.

RESULTS

IFN-beta stimulated re-epithelialization but did not reduce the number of myofibroblasts or scar tissue formation. Surprisingly, the injection of vehicle alone delayed the healing process.

CONCLUSION

IFN-beta might be suitable to stimulate re-epithelialization but it does not reduce scar tissue formation in rat palatal wound healing. The injection of agents into palatal wounds might severely impair the healing process.

Constriction of the maxillary dental arch by mucoperiosteal denudation of the palate

OBJECTIVE

This study examined the influence of two factors in the constriction of the maxillary dental arch by mucoperiosteal denudation of the palate: (1) inhibition of lateral growth and (2) medial inclination of teeth.

METHOD

Thirty-five male 20-day-old Wistar rats were divided into experimental and control groups. The experimental group had bilateral mucoperiosteum excised in the lateral one third of the palate. Methyl methacrylate resin-embedded frontal sections were prepared from both groups after alternate weekly injections of tetracycline and calcein in the dorsal subcutaneous area. The sections were observed and photographed under either a confocal laser scanning microscope, a fluorescence microscope, or both. Chronological changes in lateral palatal growth, maxillary dental arch width, and inclination of the upper first molars were examined up to 8 weeks after the operation. Paraffin-embedded frontal sections were also made and stained with Elastica van Gieson stain.

RESULTS

The scar tissue formed on the rat palate by the mucoperiosteal denudation was tightly connected to the palatal bone and teeth. The intervals between the labeling lines of the experimental group were less definite during the first 2 weeks after the operation. Increments of palatal and maxillary dental arch widths were smaller in the experimental group than in the control group. The upper first molars in the control group gradually inclined laterally, whereas those in the experimental group inclined medially with age.

CONCLUSION

Medial inclination of teeth is a stronger influence than inhibition of lateral growth on constriction of the rat maxillary dental arch.

Analysis of scar tissue distribution on rat palates: a laser Doppler flowmetric study

OBJECTIVE

The aim of this study was to evaluate the effectiveness of laser Doppler flowmetry (LDF) to discriminate postoperative scar tissue distribution on the palate.

METHODS

Nineteen male Wistar rats at the 20th postnatal day were divided into experimental and control groups. In the experimental group, lateral palatal mucoperiosteum was excised to form scar tissue on the palate. At the 11th postnatal week, changes in the palatal blood flow were recorded with LDF in both groups by occluding exposed common carotid arteries. Perfusion values of nonoccluded (stable) and occluded states and the ratio of occluded to stable states were compared for scar tissue and normal tissue areas, and also for the normal tissue areas. After the LDF measurements, India ink-injected specimens and tissue sections were prepared for histological observations.

RESULTS AND CONCLUSIONS

Scar tissue areas showed lower perfusion values both in the stable and occluded states, reflecting a lower vascular density in the scar tissue. The ratio of the occluded to stable states was higher in the scar tissue than in the normal tissue areas. In normal tissue areas, perfusion values of both the stable and occluded states appeared to vary, but the ratio did not vary among the areas. In the LDF study, the ratio of the occluded to stable states was considered to be the better parameter for discriminating scar tissue from normal tissue.

Dentoalveolar growth inhibition induced by bone denudation on palates: a study of two isolated cleft palates with asymmetric scar tissue distribution

OBJECTIVE

This report presents two cases of isolated cleft palate with asymmetric distribution of postsurgical scar tissue determined by laser Doppler flowmetry. To determine the effect of mucoperiosteal denudation of the bone on maxillary alveolar growth, the analysis of dentoalveolar structures compared the affected side to the unaffected side of each case.

METHOD

Two Japanese girls with isolated cleft palates were examined. Both subjects had undergone pushback operations (a modified version of the procedure of Wardill) for palatal repair at 18 months of age. Palatal blood flow was examined by laser Doppler flowmetry when the girls were 12 years old to determine the extent of postsurgical scar tissue over the denuded bone. To analyze the maxillary dentoalveolar structures three dimensionally, the whole surface of the upper dental cast was measured and recorded by an optical measuring device when the girls were 7 years old.

RESULTS AND CONCLUSIONS

Analysis via flowmetry showed that the palatal scar tissue area was limited to the anterior tooth region on the right (unaffected) side but extended posteriorly to the premolar region on the left (affected) side in both subjects. The two girls had similar dentoalveolar structures, with the dental and alveolar arches deflected lingually at the deciduous molar area on the affected side. There were no differences in the buccolingual inclination of deciduous molars or in the vertical growth of the alveolar processes between the affected and unaffected sides. In both girls, bone denudation in the premolar region appeared to result in less than 3 mm of displacement of the teeth palatally, with no change in lingual inclination. Any effects of scar tissue on the vertical development of the alveolus were not substantiated.