Maduración de la Sutura Palatina Media En Adolescentes y Adultos Jóvenes Chilenos: Estudio Transversal / Midpalatal Sutural Maturation in Chilean Adolescents and Young Adults: Cross-sectional Study

RESUMEN: Objetivo: Evaluar la maduración de la sutura palatina media en adolescentes y adultos jóvenes chilenos, mediante valoración morfológica de imágenes de tomografía computarizada de haz cónico del maxilar. Material y método: Se analizó la sutura palatina media de 150 sujetos entre 15 y 30 años, seleccionados desde la base de datos radiológicos de un centro universitario de salud. La maduración sutural fue evaluada en el corte axial, utilizando el método de Angelieri y cols., clasificándola en cinco etapas (A, B, C, D y E). Se utilizaron las pruebas de correlación de Pearson para medir la concordancia intra e interexaminador, y T-Student para las diferencias entre sexos. Resultados: El estado de maduración más frecuente fue C (43,3%), seguido por E (33,3%) y D (22%). En hombres, la etapa C fue más frecuente (49%), mientras que en mujeres fue la etapa E (39%). Sin embargo, no se encontraron diferencias estadísticamente significativas entre ambos sexos. Conclusiones: Aunque la mayoría de la muestra presentó una etapa tardía de maduración sutural, el 45% presentó estados de maduración sutural donde sería posible la expansión de naturaleza no quirúrgica. Debido a la variabilidad observada en adolescentes y adultos jóvenes, se recomienda la evaluación individual con imagenología 3D.

ABSTRACT: Objective: To evaluate midpalatal suture maturation in Chilean adolescents and young adults through morphological assessment of cone-beam computed tomography images of the maxilla. Materials and methods: Analysis of the midpalatal suture of 150 subjects aged between 15 and 30 was performed, selected from a university clinical center radiological database. Sutural maturation was evaluated in the axial cross-section, using the method described by Angelieri et al., classifying it in five stages (A, B, C, D and E). Pearson's correlation tests were used to assess intra- and inter-examiner agreement, and T-Student for assessing differences between genders. Results: The most frequent maturation stage was C (43.3%), followed by E (33.3%) and D (22%). In men, stage C was more frequent (49%), while in women it was stage E (39%). However, no statistically significant differences were found between genders. Conclusions: Although the majority of the sample presented a late stage of sutural maturation, 45% presented states of sutural maturation where the expansion of a non-surgical nature would be possible. Due to the variability observed in adolescents and young adults, individual evaluation with 3D imaging is recommended.

Evaluation of the suture ossification level according to age and sex in children, adolescents, and adults. A cross-sectional and observational 3D study.

OBJECTIVE: To determine the ossification level of the midpalatal suture (MPS) in children, adolescents and adults from a Peruvian sample; according to the method proposed by Angelieri et al. with cone-beam computed tomographies (CBCTs). MATERIAL AND METHODS: The sample consisted of 315 CBCTs of 168 females and 147 males. The total sample was divided into 3 groups according to age and sex: children (n=77), adolescents (n=113) and adults (n=125). The images were mainly assessed in the axial plane using the Real Scan 2.0 software. The different periods of ossification of the MPS at the level of the vertical half of the palate was defined according to the five stages of Angieleri method (from A to E). The Student t-Test, Chi-square test, Kruskal-Wallis test and Spearman's Rho test were applied. RESULTS: Chi2 test results showed that the stages of MPS ossification depended on the age of the patient by age ranges (P<0.005). Multiple comparison tests affirmed that male and female subjects in the children group had fewer ossification stages than the adolescent and adult groups (P<0.001). Meanwhile, there were no statistically significant differences between the two older age groups. Finally, there was a moderate positive correlation between the stages of ossification of the MPS and the age in the male group (Rho=0.511). CONCLUSIONS: The onset of MPS ossification was significantly related to subjects up to 12 years of age and more frequently in stages B and C in both sexes. There was no difference in MPS ossification in adolescents and adult subjects.

Periostin and matrix stiffness combine to regulate myofibroblast differentiation and fibronectin synthesis during palatal healing.

Although the matricellular protein periostin is prominently upregulated in skin and gingival healing, it plays contrasting roles in myofibroblast differentiation and matrix synthesis respectively. Palatal healing is associated with scarring that can alter or restrict maxilla growth, but the expression pattern and contribution of periostin in palatal healing is unknown. Using periostin-knockout (Postn-/-) and wild-type (WT) mice, the contribution of periostin to palatal healing was investigated through 1.5 mm full-thickness excisional wounds in the hard palate. In WT mice, periostin was upregulated 6 days post-wounding, with mRNA levels peaking at day 12. Genetic deletion of periostin significantly reduced wound closure rates compared to WT mice. Absence of periostin reduced mRNA levels of pivotal genes in wound repair, including α-SMA/acta2, fibronectin and ßigh3. Recruitment of fibroblasts and inflammatory cells, as visualized by immunofluorescent staining for fibroblast specific factor-1, vimentin, and macrophages markers Arginase-1 and iNOS was also impaired in Postn-/-, but not WT mice. Palatal fibroblasts isolated from the hard palate of mice were cultured on collagen gels and prefabricated silicon substrates with varying stiffness. Postn-/- fibroblasts showed a significantly reduced ability to contract a collagen gel, which was rescued by the exogenous addition of recombinant periostin. As the stiffness increased, Postn-/- fibroblasts increasingly differentiated into myofibroblasts, but not to the same degree as the WT. Pharmacological inhibition of Rac rescued the deficient myofibroblastic phenotype of Postn-/- cells. Low stiffness substrates (0.2 kPa) resulted in upregulation of fibronectin in WT cells, an effect which was significantly reduced in Postn-/- cells. Quantification of immunostaining for vinculin and integrinß1 adhesions revealed that Periostin is required for the formation of focal and fibrillar adhesions in mPFBs. Our results suggest that periostin modulates myofibroblast differentiation and contraction via integrinß1/RhoA pathway, and fibronectin synthesis in an ECM stiffness dependent manner in palatal healing.

Incidence and morphology of the incisive suture in CT scanning of young children and human fetuses.

PURPOSE: Incisive suture is a suture classically described on the oral face of the palate in fetuses and young children. The aim of our study was to describe the evolution of the incisive suture in human fetuses and to evaluate the incidence of this suture in a population of young children under 4 years, to determine if there is a possibility of improving the anterior growth of the maxilla, by stimulation of this suture. METHODS: One hundred and thirty CT scan images of patients aged from birth to 48 months have been studied and nine fetal palates aged from 18 to 26 weeks of development, have been scanned using high-resolution X-ray micro-computed tomography RESULTS: The CT scan images of patients showed that an incisive suture was present in 33/130 cases (25,4%). All the patients with a suture were under 2 years old. The fetal palate study showed that the suture was present in the inferior aspect of the palate (oral cavity) in all cases. The incisive suture increased from 18 to 24 weeks. At 26 weeks it stopped growing although the intercanine length increased. Considering the closure of the suture in a vertical plane, our study on fetuses has shown that the incisive suture is closing from its superior side (nasal side) to its inferior side. CONCLUSIONS: Considering all these results it appears to us that the incisive suture is partially ossified after birth, it cannot be stimulated by orthodontic appliances.

Classification of the midpalatal suture maturation in individuals older than 15 years: a cone beam computed tomographic study.

PURPOSE: The aim of this study was to classify the maturation of the midpalatal suture (MPS) in a sample of individuals aged 15 years and older. METHODS: Tomographic images in axial sections of the MPS of 289 female individuals and 198 male individuals aged between 15 and 40 years were analyzed and classified in stages of maturation (A, B, C, D, and E), stage A represents the earliest maturation stage of the suture and in stage E the fusion of the MPS has occurred in the maxilla. The Kruskal-Wallis and Student-Newman-Kells tests were used to compare the chronological ages among different maturation stages. Spearman's correlation coefficient was used to assess the correlation between patient's age and the maturation stages of the MPS. RESULTS: Stage A was not observed in the sample. Stages B and C represent, respectively, 1.03% and 34.09% of the sample, stage D was found in 16.63% of the sample while stage E was the most prevalent stage found (48.25%). For females, it was revealed no statistically significant difference in the mean ages among stages C, D and E (p = 0.4753). For males, a statistically significant difference was observed, with the mean age of individuals in stages D and E of the MPS maturation higher than in other stages (p = 0.0001). There was a significant, but weak, correlation between patient's age and the maturation stages of the suture (rs = 0.11/p = 0.01). CONCLUSION: No individuals in stage A of suture maturation were found and stage B was identified in only 1% of the sample. The majority of the patients (64.88%) presented at least partial fusion of the MPS (stages D and E).

Skeletal Age-related Changes of Midpalatal Suture Densities in Skeletal Maxillary Constriction Patients: CBCT Study.

AIM: To determine if density measurements of the midpalatal suture and cervical vertebral maturation index (CVMI) are related, and to investigate if CVMI could help in predicting of the developmental status of the midpalatal suture. MATERIALS AND METHODS: Cone-beam computed tomography (CBCT) images of 95 skeletal maxillary constriction patients (aged 8 to 18 years) were examined. The maturational stages of the cervical vertebrae were visually defined, and midpalatal suture density in the anterior region, the middle region, and the posterior region were measured. One-way ANOVA and Fisher's least significant difference (LSD) post-hoc test were used for statistical assessment. RESULTS: Significant differences were found in MPDS: in anterior region between (c1,c2,c3,c4) and (c5,c6) stages, in middle region between (c1,c2,c3) and (c5,c6) stages, and in posterior region between (c1,c2,c3) and (c4,c5,c6) stages. CONCLUSION: Midpalatal suture densities in all regions increase with skeletal maturation advancement.The significant increase after puberty may have the key role in decreasing the skeletal effects of RME after that age. Clinical significances: It is important to assess the midpalatal suture density to choose between rapid maxillary expansion (RME) and surgically assisted rapid maxillary expansion (SARME). This study revealed a significant increase in the midpalatal suture density after puberty. Thus, it may better to perform RME before puberty.

Do gender and age influence hard palate dimensions? A systematic review. / O gênero e a idade influenciam as dimensões do palato duro? Revisão sistemática da literatura.

PURPOSE: Analyze the influence of gender and age on hard palate dimensions and verify the reference parameters available in the literature. RESEARCH STRATEGIES: Two reviewers independently performed a search at the Cochrane Library, PubMed-Medline and Web of Knowledge databases using descriptors according to the syntax rules of each database. SELECTION CRITERIA: Observational or experimental human studies evaluating the dimensions of the hard palate or maxillary dental arch, with at least one transverse, vertical or sagittal plane measurement, in normal occlusions or class I malocclusions, and comparisons of the dimensions between genders and/or ages. DATA ANALYSIS: Descriptive analysis with the following subdivisions: design, sample, evaluation instruments, measurements in millimeters, and statistical analysis. Quality of the included studies was verified by the Newcastle - Ottawa Quality scale. RESULTS: Eighteen studies were selected and 11 presented results for hard palate or maxillary dental arch dimensions according to gender, six in age and gender and one in age only. CONCLUSION: The dimensions were larger in males and progressive increase in the measurements was observed from birth to the permanent dentition period.

OBJETIVO: Analisar a influência do gênero e da idade nas dimensões do palato duro, bem como verificar os parâmetros de referência disponíveis na literatura. ESTRATÉGIA DE PESQUISA: Dois examinadores realizaram a pesquisa de forma independente nas bases de dados Cochrane Library, PubMed-Medline e Web of Knowledge utilizando os descritores de acordo com as regras de sintaxe de cada banco de dados. CRITÉRIOS DE SELEÇÃO: Estudos em humanos observacionais ou experimentais, que avaliaram as dimensões do palato duro ou do arco dentário maxilar com pelo menos uma mensuração no plano transversal, vertical ou sagital em oclusões normais ou más oclusões classe I e que realizaram comparações das dimensões entre os gêneros e/ou idades. ANÁLISE DE DADOS: Análise descritiva, seguindo subdivisões: delineamento, amostra, instrumentos de avaliação, medidas em milímetros e análise estatística. A qualidade dos estudos incluídos foi verificada através da escala "Newcastle - Ottawa Quality". RESULTADOS: Foram selecionados 18 estudos. Destes, 11 apresentaram resultados das dimensões do palato duro ou do arco dentário maxilar conforme o gênero, seis em idade e gênero e um somente em idade. CONCLUSÃO: As medidas foram maiores no gênero masculino e houve um aumento progressivo nas dimensões do nascimento até o período de dentição permanente.

Gender and growth variation in palatal bone thickness and density for mini-implant placement.

BACKGROUND: The objective was to compare the palatal bone thickness (PBT) and palatal bone density (PBD) in the anterior, middle, and posterior part of the palate in males and females. METHODS: This retrospective study reviewed cone beam computed tomography scans of 359 patients. The scans were divided into 99 growing males, 105 growing females, 74 non-growing males, and 81 non-growing females. The measurements of PBT and PBD were made in between the canine and first premolar, the first premolar and second premolar, the second premolar and first molar, and the first molar and second molar. The measurements were made in the center of the palate and 4 mm away from the center. ANOVA was used to analyze the PBT and PBD in different areas between four different groups. RESULTS: The PBT was lower (P <  0.0001) as we moved from the anterior to the posterior palate. The PBT was more (P <  0.001) in the center of the palate than 4 mm away from the center, except in between the canine and first premolar. The growing male and non-growing male had higher (P <  0.0001) PBT than the growing female and non-growing female in between the canine and first premolar and the first premolar and second premolar both in the center and 4 mm away from it. The PBD was higher (P <  0.05) in between the canine and first premolar area at the center of the palate and between the second premolar and first molar 4 mm away from the center in all the experimental groups. CONCLUSIONS: There exists a definite gender and growth variation in the PBT and PBD in different parts of the palate. Palatal bone thickness between the males and females revealed that the males had significantly higher PBT than the females.

Evaluation of a Sample of Patients With Unilateral Cleft Lip and Palate Treated With a Two-Stage Protocol.

The aim of this paper was to assess growth, speech, and aesthetic results at the completion of growth in patients with unilateral cleft lip and palate treated with the 2 stages Milan surgical protocol.Craniofacial growth was evaluated with cephalometric analysis and a theoretical need for orthognathic surgery.Nasolabial appearance was qualitatively assessed using the Asher McDade Aesthetic Index.Speech was assessed using the Gos.Sp.Ass '98 modified for Italian language scoring system.Burden of care was recorded in terms of number of secondary surgical procedures. All of the patients were treated and evaluated at San Paolo Hospital, Smile House, Milan.Fifty-two consecutive patients treated by the same surgeon were recalled, 12 patients did not come for assessment.The first surgical step (average age of 6 months) was cheilorhinoplasty (Millard modified Delaire technique) and soft palate rapair (Pigott). The second step (average age of 35 months) was hard palate and alveolar repair performed simultaneously with an early secondary gengivo alveolo plasty. Fifty-six percent of the patients did not need further surgery after the 2-stage surgery protocol.The 2-stage surgical protocol of Milano, Smile House, seems to be effective for treatment of unilateral cleft lip and palate, with good results in terms of speech, labial appearance, and alveolar cleft management. Nevertheless, maxillary growth was moderately impaired by the protocol.

Unilateral Cleft Lip and Palate Surgical Protocols and Facial Growth Outcomes.

BACKGROUND: Adequate dentofacial growth is an objective of unilateral cleft lip and palate treatment. No study exists, comparing the dental arch of 5-year-old relationship after 2 treatment protocols: one with single-stage palatoplasty and another with delayed hard palate closure (DHPC). The authors hypothesized that the DHPC protocol provides better dentofacial growth. METHODS: A single-center, single-surgeon Randomized Clinical Trial was performed to evaluate the maxillomandibular relationships in 2 groups. The intervention group (GI) underwent palatoplasty with DHPC between ages 3 and 4 years; the control group (CG) underwent complete palatoplasty between 9 and 15 months. The authors evaluated oronasal fistulae rates.The dental arch relationship was evaluated via blinded panels using the Five Year Old Index.Kappa statistics were calculated to assess reliability. Trials were statistically tested with the t test and chi-squared test. RESULTS: Sixty-four patients constituted the study sample. The incidence of oronasal fistulae was 9.4% (GI) and 6.7% (CG). Sixty-two models with an average age of 55 months were available for analysis. Good intra- and inter-rater reliabilities (0.73-0.93 and 0.60-0.94, respectively) were obtained. Average index scores ranging from 2.04 (GI) to 2.76 (CG) were significantly different (P = 0.007). Significant between-group differences (P = 0.006) were found in scores, 1 and 2 in the GI (74%) and CG (52%). When the distributions were compared by the median, a difference was found (P = 0.024) in score, 1 between the GI (31.2%) and CG (3.3%). CONCLUSIONS: Although the DHPC protocol yielded better outcomes relating to dentofacial growth, other protocols should be investigated and findings verified by other researchers.

Midpalatal suture: evaluation of the morphological maturation stages via bone density.

BACKGROUND: To investigate the relationship between the morphological maturation stages of the midpalatal suture and its bone densities. METHODS: The sample consisted of 91 subjects aged 8-18 years who underwent cone beam computed tomography. All images were examined to classify morphological maturation of the midpalatal suture to five groups according to Angelieri et al. Bone density of the midpalatal suture was measured at the maxillary and palatal regions. Kruskal-Wallis and Mann-Whitney U tests were used to analyze the difference between groups. RESULTS: Bone density of the midpalatal suture was significantly higher in the palatal region in E stage and in the maxillary region in D and E stages. CONCLUSIONS: It is concluded that the change in bone density of the midpalatal suture between the morphological maturation stages supports their reliability in clinical application.

Tomographic evaluation of the maturation stage of the midpalatal suture in postadolescents.

INTRODUCTION: In this study, we aimed at evaluating the maturation stage of the midpalatal suture based on its morphology, using cone-beam computed tomography images in young postadolescents. METHODS: The sample comprised 112 patients, 68 female and 44 male, aged 16 to 20 years, consecutively selected from 2 private orthodontic clinics. They had cone-beam computed tomography images in their initial orthodontic files, requested for orthodontic planning purposes. These images were exported to the Invivo 5 program (Anatomage, San Jose, Calif), where axial sections were obtained from the midpalatal suture for morphologic evaluation. Two previously calibrated examiners interpreted the images to establish the stage of sutural maturation of each patient according to its morphologic characteristics in 5 maturational stages (A, B, C, D, and E). The kappa coefficient was applied for intraexaminer and interexaminer agreements, and their values were 0.87 and 0.89, respectively. RESULTS: The maturational stages most often observed in this study were C, D, and E, (91.9%). In males, stage C was present in 52.3%; for females this prevalence was 39.7%. CONCLUSIONS: The high prevalence of stage C in this age group may justify a clinical study to confirm the good prognosis for rapid maxillary expansion in postadolescents.

FGF8 Signaling Alters the Osteogenic Cell Fate in the Hard Palate.

Fibroblast growth factor (FGF) signaling has been implicated in the regulation of osteogenesis in both intramembranous and endochondral ossifications. In the developing palate, the anterior bony palate forms by direct differentiation of cranial neural crest (CNC)-derived mesenchymal cells, but the signals that regulate the osteogenic cell fate in the developing palate remain unclear. In the present study, we investigated the potential role of FGF signaling in osteogenic fate determination of the palatal mesenchymal cells. We showed that locally activated FGF8 signaling in the anterior palate using a Shox2Cre knock-in allele and an R26RFgf8 allele leads to a unique palatal defect: a complete loss of the palatine process of the maxilla as well as formation of ectopic cartilaginous tissues in the anterior palate. This aberrant developmental process was accompanied by a significantly elevated level of cell proliferation, which contributes to an abnormally thickened palatal tissue, where the palatine process of the maxilla would normally form, and by a complete inhibition of Osterix expression, which accounts for the lack of bone formation. The coexpression of Runx2 initially with Sox9 and subsequently with Col II in the ectopic cartilaginous tissues indicates a conversion of osteogenic fate to a chondrogenic one. Consistent with the unique palatal phenotype, RNA-Sequencing analysis revealed that the augmented FGF8 signaling downregulated genes involved in ossification, biomineral tissue development, and bone mineralization but upregulated genes involved in cell proliferation, cartilage development, and cell fate commitment, which was further supported by quantitative real-time reverse transcription polymerase chain reaction validation of selected genes. Our results demonstrate that FGF8 signaling functions as a negative regulator of osteogenic fate and is sufficient to convert a subset of CNC cell-derived mesenchymal cells into cartilage in the anterior hard palate, which will have implications in future directed differentiation of CNC-derived precursor cells for clinical application.

O gênero e a idade influenciam as dimensões do palato duro? Revisão sistemática da literatura / Do gender and age influence hard palate dimensions? A systematic review

RESUMO Objetivo Analisar a influência do gênero e da idade nas dimensões do palato duro, bem como verificar os parâmetros de referência disponíveis na literatura. Estratégia de pesquisa Dois examinadores realizaram a pesquisa de forma independente nas bases de dados Cochrane Library, PubMed-Medline e Web of Knowledge utilizando os descritores de acordo com as regras de sintaxe de cada banco de dados. Critérios de seleção Estudos em humanos observacionais ou experimentais, que avaliaram as dimensões do palato duro ou do arco dentário maxilar com pelo menos uma mensuração no plano transversal, vertical ou sagital em oclusões normais ou más oclusões classe I e que realizaram comparações das dimensões entre os gêneros e/ou idades. Análise de dados Análise descritiva, seguindo subdivisões: delineamento, amostra, instrumentos de avaliação, medidas em milímetros e análise estatística. A qualidade dos estudos incluídos foi verificada através da escala "Newcastle - Ottawa Quality". Resultados Foram selecionados 18 estudos. Destes, 11 apresentaram resultados das dimensões do palato duro ou do arco dentário maxilar conforme o gênero, seis em idade e gênero e um somente em idade. Conclusão As medidas foram maiores no gênero masculino e houve um aumento progressivo nas dimensões do nascimento até o período de dentição permanente.

ABSTRACT Purpose Analyze the influence of gender and age on hard palate dimensions and verify the reference parameters available in the literature. Research strategies Two reviewers independently performed a search at the Cochrane Library, PubMed-Medline and Web of Knowledge databases using descriptors according to the syntax rules of each database. Selection criteria Observational or experimental human studies evaluating the dimensions of the hard palate or maxillary dental arch, with at least one transverse, vertical or sagittal plane measurement, in normal occlusions or class I malocclusions, and comparisons of the dimensions between genders and/or ages. Data analysis Descriptive analysis with the following subdivisions: design, sample, evaluation instruments, measurements in millimeters, and statistical analysis. Quality of the included studies was verified by the Newcastle - Ottawa Quality scale. Results Eighteen studies were selected and 11 presented results for hard palate or maxillary dental arch dimensions according to gender, six in age and gender and one in age only. Conclusion The dimensions were larger in males and progressive increase in the measurements was observed from birth to the permanent dentition period.

Growth of the hard palate in infants with Down syndrome compared with healthy infants-A retrospective case control study.

OBJECTIVE: To investigate morphological differences of the hard palate in infants with Down syndrome (DS) compared with a volumetric-matched control group (CG). METHODS: Trial design: retrospective case control study. Based on inclusion and exclusion criteria, plaster casts of edentulous maxillae of 40 DS infants (20 females and 20 males, aged 221.3 ± 132.4 days) and 40 CG infants (20 females and 20 males, aged 53.9 ± 87.2 days) were digitized and converted into 3-dimensional stereolithography data. An automated landmark- and investigator-independent method for assessing two-dimensional measurements such as width, depth, and length of palate, as well as palatal index and the 3-dimensional volume, were used. RESULTS: Matching DS and healthy CG infants by age, we found reduced sizes in all linear and volumetric measurements in the DS group. Matching both groups by palatal volume, we found no differences between the groups according to palatal width (p = .93), palatal depth (p = .32), and palatal index (p = .31). Control infants with the same palatal volume compared with the DS infants were about 151 days younger, 95%-CI = [102, 200] (Hodges-Lehmann estimator). Except for palatal length and palatal volume, the growth pattern of DS palates decreased irregularly at age 6 to 9 months. CONCLUSIONS: The palate of DS infants in the first 6 to 9 month of life is of normal shape but considerably smaller compared with healthy normals. From 6 to 9 months onward, the growth pattern of the hard palate in DS infants decreases irregularly. High-arch-constricted palates could, therefore, be interpreted as secondarily acquired in later life. We therefore speculate that it could be advantageous to begin oral muscular stimulating therapy between 6 and 9 months of age which may prevent palatal shape alterations and enhance oral function which also contributes to maxillary development.

Cone beam computed tomography evaluation of midpalatal suture maturation in adults.

The aim of this study was to evaluate midpalatal suture maturation in adults, as observed in cone beam computed tomography (CBCT) images. CBCT scans from 78 subjects (64 female and 14 male, age range from 18 to 66 years) were evaluated. Midpalatal suture maturation was verified on the central cross-sectional axial slice in the superior-inferior dimension of the palate, using methods validated previously. Intra-examiner agreement was analyzed by weighted kappa test. Multinomial logistic regression was used to test whether sex and chronological age (adults <30 years or ≥30 years) could be used as a predictor for the maturational stages of the midpalatal suture. The majority of the adults presented a fused midpalatal suture in the palatine (stage D) and/or maxillary bones (stage E). However, the midpalatal suture was not fused in 12% of the subjects. Sex and chronological age were not significant predictors of the maturational stages of the midpalatal suture. The individual assessment of midpalatal suture maturation by way of CBCT images may provide reliable information critical to making the clinical decision between rapid maxillary expansion and surgically assisted rapid maxillary expansion for the treatment of maxillary atresia in adults.

Novel methodologies and technologies to assess mid-palatal suture maturation: a systematic review.

INTRODUCTION: A reliable method to assess midpalatal suture maturation to drive clinical decision-making, towards non-surgical or surgical expansion, in adolescent and young adult patients is needed. The objectives were to systematically review and evaluate what is known regarding contemporary methodologies capable of assessing midpalatal suture maturation in humans. METHODS: A computerized database search was conducted using Medline, PubMed, Embase and Scopus to search the literature up until October 5, 2016. A supplemental hand search was completed of references from retrieved articles that met the final inclusion criteria. RESULTS: Twenty-nine abstracts met the initial inclusion criteria. Following assessment of full articles, only five met the final inclusion criteria. The number of subjects involved and quality of studies varied, ranging from an in-vitro study using autopsy material to prospective studies with in vivo human patients. Three types of evaluations were identified: quantitative, semi-quantitative and qualitative evaluations. Four of the five studies utilized computed tomography (CT), while the remaining study utilized non-invasive ultrasonography (US). No methodology was validated against a histological-based reference standard. CONCLUSIONS: Weak limited evidence exists to support the newest technologies and proposed methodologies to assess midpalatal suture maturation. Due to the lack of reference standard validation, it is advised that clinicians still use a multitude of diagnostic criteria to subjectively assess palatal suture maturation and drive clinical decision-making.

Evaluation of the stiffness characteristics of rapid palatal expander screws.

BACKGROUND: The aim of this study is to evaluate the mechanical properties of the screws used for rapid expansion of the upper jaw. METHODS: Ten types of expansion screw were assessed, seven with four arms: Lancer Philosophy 1, Dentaurum Hyrax Click Medium, Forestadent Anatomic Expander type "S", Forestadent Anatomic Expander type "S" for narrow palates, Forestadent Memory, Leone A 2620-10 with telescopic guide, and Leone A 0630-10 with orthogonal arms; and three with two arms: Dentaurum Variety S.P., Target Baby REP Veltri, and Leone A 362113. A test expander with the mean dimensions taken from measurements on a sample of 100 expanders was constructed for each screw. The test expanders were connected to the supports of an Instron 4467 (Instron Corp., USA) mechanical testing machine equipped with a 500 N load cell, and the compression force exerted after each activation was measured. The mean forces expressed by the two- and four-arm expanders were then compared. RESULTS: After five activations, the forces expressed by the two-arm devices were double than those expressed by the four-arm devices on average (224 ± 59.9 N vs. 103 ± 32.9 N), and such values remained high after subsequent activations. CONCLUSIONS: The expanders tested demonstrated stiffness characteristics compatible with opening of the palatine sutures in pre-adolescent patients. The stiffness of such devices can be further increased during the construction phase.

Effect of sex steroids on bone formation in an orthopedically expanded suture in rats : An immunohistochemical and computed tomography study.

OBJECTIVE: The purpose of this work was to evaluate the effects of sex steroids on bone formation in response to midpalatal suture expansion by means of histological and immunohistochemical examinations and computed tomography (CT). MATERIALS AND METHODS: A total of 32 male and 32 female 12-week-old Wistar rats were divided into four groups per gender. Testosterone was administered to the castrated experimental male rats, estrogen to castrated experimental female rats. Saline solution was given subcutaneously to the male and female control, sham, and castration groups during expansion and retention periods, which lasted 7 and 5 days, respectively. The expansion amount was measured with a digital caliper. The density of the new bone in the expansion area was measured via CT. RESULTS: Histological and CT evaluation revealed that the number of osteoblasts and density of the new bone was higher in male and female experimental groups than in all the other groups. When scores of staining intensity were compared, the experimental groups demonstrated statistically significant greater immunoreactivity in the osteoblasts compared to castrated-only groups. Bone density was higher in the female experimental group than in the others, and higher in the male experimental group than in the others. Expansion amounts in the castrated groups were higher than in the others (p < 0.05). CONCLUSION: Raising the levels of sex steroids in rats revealed positive effects on bone formation in the midpalatal suture in response to expansion. Increased sex steroid levels can reduce the time needed for retention.

Midpalatal suture maturation: classification method for individual assessment before rapid maxillary expansion.

INTRODUCTION: In this study, we present a novel classification method for individual assessment of midpalatal suture morphology. METHODS: Cone-beam computed tomography images from 140 subjects (ages, 5.6-58.4 years) were examined to define the radiographic stages of midpalatal suture maturation. Five stages of maturation of the midpalatal suture were identified and defined: stage A, straight high-density sutural line, with no or little interdigitation; stage B, scalloped appearance of the high-density sutural line; stage C, 2 parallel, scalloped, high-density lines that were close to each other, separated in some areas by small low-density spaces; stage D, fusion completed in the palatine bone, with no evidence of a suture; and stage E, fusion anteriorly in the maxilla. Intraexaminer and interexaminer agreements were evaluated by weighted kappa tests. RESULTS: Stages A and B typically were observed up to 13 years of age, whereas stage C was noted primarily from 11 to 17 years but occasionally in younger and older age groups. Fusion of the palatine (stage D) and maxillary (stage E) regions of the midpalatal suture was completed after 11 years only in girls. From 14 to 17 years, 3 of 13 (23%) boys showed fusion only in the palatine bone (stage D). CONCLUSIONS: This new classification method has the potential to avoid the side effects of rapid maxillary expansion failure or unnecessary surgically assisted rapid maxillary expansion for late adolescents and young adults.