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1.
Plast Reconstr Surg ; 145(4): 790e-802e, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32221226

RESUMO

BACKGROUND: Apert syndrome causes normal or enlarged intracranial volume overall as patients grow. This study aimed to trace the segmental anterior, middle, and posterior cranial fossae volume and structural morphology in these patients, to help discern a more focused and individualized surgical treatment plan for patients with Apert syndrome. METHODS: This study included 82 preoperative computed tomographic scans (Apert, n = 32; control, n = 50) divided into five age-related subgroups. The scans were measured using image processing and three-dimensional modeling software. RESULTS: The middle cranial fossa volume was increased and was the earliest change noted. It was increased by 45 percent (p = 0.023) compared with controls before 6 months of age and remained increased into adulthood (161 percent, p = 0.016), with gradually increasing severity. The anterior and posterior cranial fossae volumes also increased, by 35 percent (p = 0.032) and 39 percent (p = 0.007), respectively. Increased depth of cranial fossae contributed most to the increase in volumes of patients with Apert syndrome, with correlation coefficients of 0.799, 0.908, and 0.888 for anterior, middle, and posterior cranial fossa, respectively. The intracranial volume was increased 12 percent (p = 0.098) across the entire test age range (0 to 26 years old), but only had statistical significance during the age range of 6 to 18 years (22 percent, p = 0.001). CONCLUSIONS: Malformation of the middle cranial fossa is an early, perhaps the initial, pivotal cranial morphologic change in Apert syndrome. Increased cranial fossae depth is an inherent characteristic of the maldevelopment. Normalization of cranial volume and circumference overall may not achieve a normal skull structure, as it does not correct regional craniocerebral disproportion.


Assuntos
Acrocefalossindactilia/cirurgia , Cefalometria/métodos , Desenvolvimento Infantil , Planejamento de Assistência ao Paciente , Base do Crânio/patologia , Acrocefalossindactilia/diagnóstico por imagem , Acrocefalossindactilia/patologia , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Lactente , Recém-Nascido , Masculino , Tamanho do Órgão , Estudos Retrospectivos , Base do Crânio/diagnóstico por imagem , Base do Crânio/crescimento & desenvolvimento , Tomografia Computadorizada por Raios X , Adulto Jovem
2.
Neurochirurgie ; 65(5): 216-220, 2019 Nov.
Artigo em Francês | MEDLINE | ID: mdl-31568778

RESUMO

The skull base is a part of the neuro-cranium formed by endochondral ossification. The embryological origin of the skull base is not perfectly known, but there seems to be an anterior region derived from the neural crest and a posterior part derived from the mesoderm. Further studies are needed to define reliable presumptive maps. The origin of the different components of the occipital bone is just as poorly known. Much fundamental work remains to be done to suggest any solution to these problems in humans.


Assuntos
Base do Crânio/crescimento & desenvolvimento , Animais , Humanos , Crista Neural/embriologia , Crista Neural/crescimento & desenvolvimento , Osso Occipital/embriologia , Osso Occipital/crescimento & desenvolvimento , Base do Crânio/embriologia
3.
Keio J Med ; 68(2): 42, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31243185

RESUMO

Development of the skeleton is mediated through two distinct ossification mechanisms. Craniofacial bones are formed mainly through intramembranous ossification, a mechanism different from endochondral ossification required for development of the body skeleton. The skeletal structures are quite distinct between the two, thus they are likely to have their unique stem cell populations. The sutures serve as the growth center critical for healthy development of the craniofacial skeleton. Defects in suture morphogenesis cause its premature closure, resulting in development of craniosynostosis, a devastating disease affecting 1 in ~2,500 individuals. The suture mesenchyme has been postulated to act as the niche of skeletal stem cells essential for calvarial morphogenesis. However, very limited knowledge is available for suture biology and suture stem cells (SuSCs) have yet to be isolated. Here we report the first evidence for identification and isolation of a stem cell population residing in the suture midline. Genetic labeling of SuSCs shows their ability to self-renew and continually give rise to mature cell types over a 1-year monitoring period. They maintain their localization in the niches constantly produce skeletogenic descendants during calvarial development and homeostastic maintenance. Upon injury, SuSCs expand drastically surrounding the skeletogenic mesenchyme, migrate to the damaged site and contribute directly to skeletal repair in a cell autonomous fashion. The regeneration, pluripotency and frequency of SuSCs are also determined using limiting dilution transplantation. In vivo clonal expansion analysis demonstrates a single SuSC capable of generating bones. Furthermore, SuSC transplantation into injured calvaria facilitates the healing processes through direct engraftments. Our findings demonstrate SuSCs are bona fide skeletal stem cells ideally suited for cell-based craniofacial bone therapy as they possess abilities to engraft, differentiate.(Presented at the 1980th Meeting, April 16, 2019).


Assuntos
Desenvolvimento Ósseo/fisiologia , Suturas Cranianas/citologia , Ossos Faciais/citologia , Mesoderma/citologia , Células-Tronco/citologia , Animais , Regeneração Óssea/fisiologia , Suturas Cranianas/crescimento & desenvolvimento , Suturas Cranianas/fisiologia , Craniossinostoses/patologia , Ossos Faciais/crescimento & desenvolvimento , Ossos Faciais/fisiologia , Humanos , Mesoderma/fisiologia , Morfogênese/fisiologia , Osteogênese/fisiologia , Base do Crânio/citologia , Base do Crânio/crescimento & desenvolvimento , Base do Crânio/fisiologia , Coluna Vertebral/citologia , Coluna Vertebral/crescimento & desenvolvimento , Coluna Vertebral/fisiologia , Células-Tronco/fisiologia
4.
World Neurosurg ; 127: 549-558, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30092478

RESUMO

Patients with complex, multisutural, and syndromic craniosynostosis (CSO) frequently exhibit intracranial hypertension. The intracranial hypertension cannot be entirely attributed to the craniocephalic disproportion with calvarial restriction because cranial vault expansion has not consistently alleviated elevated intracranial pressure. Evidence has most strongly supported a multifactorial interaction, including venous hypertension along with other pathogenic processes. Patients with CSO exhibit marked venous anomalies, including stenosis of the jugular-sigmoid complex, transverse sinuses, and extensive transosseous venous collaterals. These abnormal intracranial-extracranial occipital venous collaterals might represent anomalous development, with persistence and subsequent enlargement of channels normally present in the fetus, either as a primary defect or as nonregression in response to failure of the development of the jugular-sigmoid complexes. It has been suggested by some investigators that venous hypertension in patients with CSO could be treated directly via jugular foraminoplasty, venous stenting, or jugular venous bypass, although these options are not in common clinical practice. Obstructive sleep apnea, occurring as a consequence of midface hypoplasia, can also contribute to intracranial hypertension in patients with syndromic CSO. Thus, correction of facial deformities, as well as posterior fossa decompression, could also play important roles in the treatment of intracranial hypertension. Determining the precise mechanistic underpinnings underlying intracranial hypertension in any given patient with CSO requires individualized evaluation and management.


Assuntos
Craniossinostoses/complicações , Hipertensão Intracraniana/complicações , Malformação de Arnold-Chiari/complicações , Malformação de Arnold-Chiari/cirurgia , Malformações Vasculares do Sistema Nervoso Central/complicações , Circulação Colateral/fisiologia , Craniossinostoses/cirurgia , Humanos , Hipertensão/complicações , Hipertensão/cirurgia , Hipertensão Intracraniana/cirurgia , Veias Jugulares/anormalidades , Exame Físico/métodos , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais/fisiologia , Base do Crânio/crescimento & desenvolvimento , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/cirurgia
5.
PLoS One ; 13(12): e0208999, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30566462

RESUMO

That great ape endocranial shape development persists into adolescence indicates that the splanchnocranium succeeds brain growth in driving endocranial development. However, the extent of this splanchnocranial influence is unknown. We applied two-block partial least squares analyses of Procrustes shape variables on an ontogenetic series of great ape crania to explore the covariation of the endocranium (the internal braincase) and splanchnocranium (face, or viscerocranium). We hypothesized that a transition between brain growth and splanchnocranial development in the establishment of final endocranial form would be manifest as a change in the pattern of shape covariation between early and adolescent ontogeny. Our results revealed a strong pattern of covariation between endocranium and splanchnocranium, indicating that chimpanzees, gorillas, and orangutans share a common tempo and mode of morphological integration from the eruption of the deciduous dentition onwards to adulthood: a reflection of elongating endocranial shape and continuing splanchnocranial prognathism. Within this overarching pattern, we noted that species variation exists in magnitude and direction, and that the covariation between the splanchnocranium and endocranium is somewhat weaker in early infancy compared to successive age groups. When correcting our covariation analyses for allometry, we found that an ontogenetic signal remains, signifying that allometric variation alone is insufficient to account for all endocranial-splanchnocranial developmental integration. Finally, we assessed the influence of the cranial base, which acts as the interface between the face and endocranium, on the shape of the vault using thin-plate spline warping. We found that not all splanchnocranial shape changes during development are tightly integrated with endocranial shape. This suggests that while the developmental expansion of the brain is the main driver of endocranial shape during early ontogeny, endocranial development from infancy onwards is moulded by the splanchnocranium in conjunction with the neurocranium.


Assuntos
Hominidae/anatomia & histologia , Base do Crânio/anatomia & histologia , Crânio/anatomia & histologia , Crânio/crescimento & desenvolvimento , Animais , Evolução Biológica , Encéfalo/anatomia & histologia , Encéfalo/crescimento & desenvolvimento , Feminino , Análise dos Mínimos Quadrados , Masculino , Modelos Biológicos , Crânio/diagnóstico por imagem , Base do Crânio/diagnóstico por imagem , Base do Crânio/crescimento & desenvolvimento , Especificidade da Espécie , Tomografia Computadorizada por Raios X
6.
J Indian Soc Pedod Prev Dent ; 36(2): 206-212, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29970640

RESUMO

Aims: The aim of the present work was to evaluate the dentoskeletal effects of swallowing occlusal contact intercept appliance (SOCIA) III in pseudo Class III malocclusion treatment. Materials and Methods: Thirty-six patients (mean age: 9.46 years old) with pseudo-Class III malocclusion and 22 pseudo-Class III untreated controls (mean age: 8.7 years old) were selected and examined. All patients presented with a cervical stage CS2, CS3, or CS4. Patients with CS5 were not enrolled in the study. Cephalometric analysis was performed before phase 1 treatment (T1) and immediately following phase 2 treatment (T2). Statistical Analysis: Paired t-test and independent t-test. Results: SOCIA III had skeletal and dental effects. The main effects of SOCIA III were on the midface with an effective increase of the sagittal growth (cranial base P < 0.001, anterior cranial base (ACB) P < 0.001, and maxilla growth P < 0.001) and vertical growth (anterior facial height P < 0.001). The effects of SOCIA on the mandible were a control of mandibular postrotation (P = 0.82) and the sagittal growth (P < 0.007). At the end of the treatment, a normal overjet was achieved (P < 0.001). Conclusions: The SOCIA III effects are resumed as follow: (a) an effective maxillary sagittal increase on the sagittal plane; (b) a vertical mandibular control; (c) a resolution of overjet; (d) no increase of overbite; (e) a stimulation of ACB growth.


Assuntos
Má Oclusão de Angle Classe III/terapia , Desenho de Aparelho Ortodôntico , Aparelhos Ortodônticos Funcionais , Cefalometria , Criança , Deglutição , Humanos , Má Oclusão de Angle Classe III/diagnóstico por imagem , Má Oclusão de Angle Classe III/fisiopatologia , Mandíbula/crescimento & desenvolvimento , Maxila/crescimento & desenvolvimento , Radiografia , Base do Crânio/crescimento & desenvolvimento
7.
J Craniofac Surg ; 29(5): 1174-1180, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29762326

RESUMO

AIM: This study chronicles skull base and face development in nonsyndromic unilateral coronal synostosis (UCS) during infancy, to characterize the mechanistic progression of facial dysmorphology. METHODS: Computed tomography scans from 51 subjects were reviewed (26 UCS, 25 controls) and data were reconstructed. Patients were stratified into 5 age groups. A series of measurements were taken from the reconstructions. RESULTS: All patients had a unilaterally fused coronal suture at the time of analysis. Asymmetry of the sphenoid wings was present across all age groups. The sphenoid wing ipsilateral to the fused suture consistently had a more acute angle from the midline. At 19 days of age, ipsilateral nasal root and cribriform plate deviation are noted, as well as increased contralateral zygoma antero-posterior length. Patients younger than 2 months also had elongated posterior cranial bases. At 2 to 3 months of age, the cranial base widens in the anterior portion of the middle cranial fossa with an increased ipsilateral pterion to sella distance. The most delayed change observed was the increase in contralateral orbital rim angle at 7 to 12 months of age compared to normal. CONCLUSION: After suture fusion, sphenoid wing changes are among the earliest restructural malformations to take place. This suggests that the cascade of dysmorphology in UCS originates in the cranial vault, then progresses to the skull base, and lastly to the facial structures. Ipsilateral orbital changes are early facial changes in UCS that begin before 2 months of age. This is then followed by changes in the contralateral face later in development.


Assuntos
Craniossinostoses/diagnóstico por imagem , Craniossinostoses/patologia , Crânio/crescimento & desenvolvimento , Crânio/patologia , Animais , Osso Etmoide/diagnóstico por imagem , Osso Etmoide/crescimento & desenvolvimento , Osso Etmoide/patologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Órbita/diagnóstico por imagem , Órbita/crescimento & desenvolvimento , Órbita/patologia , Crânio/diagnóstico por imagem , Base do Crânio/diagnóstico por imagem , Base do Crânio/crescimento & desenvolvimento , Base do Crânio/patologia , Osso Esfenoide/diagnóstico por imagem , Osso Esfenoide/crescimento & desenvolvimento , Osso Esfenoide/patologia , Tomografia Computadorizada por Raios X , Zigoma/diagnóstico por imagem , Zigoma/crescimento & desenvolvimento , Zigoma/patologia
8.
J Oral Maxillofac Surg ; 76(11): 2388-2397, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29679588

RESUMO

PURPOSE: Submucous cleft palate (SMCP) is a particular subtype of cleft palate deformity; research related to the craniofacial features of patients with SMCP is comparatively rare. The study objective was to perform a cephalometric comparison of the craniofacial features of patients with SMCP and non-cleft controls at different ages. MATERIALS AND METHODS: The sample in this cross-sectional study was composed of 2 groups: SMCP patients and non-cleft controls. The primary predictor variables were study group (cleft and non-cleft) and age. Age was divided into 3 groups. The outcome variables of interest were craniofacial measurements. The measurements used reflect cranial length, cranial angle, maxillary sagittal length and protrusion, maxillary vertical height, pharyngeal depth, facial height, mandibular length and protrusion, mandibular plane angle, and intermaxillary relation. Adjusted cephalometric craniofacial measurements between the groups were compared in 3 age groups using generalized linear models after being adjusted for age and gender. RESULTS: The study included 60 SMCP patients and 60 non-cleft controls. SMCP patients and non-cleft controls were divided into 3 subgroups: those aged 5 to 7 years, those aged 9 to 11 years, and those aged 18 to 30 years. Patients with SMCP at age 5 to 7 years showed a shortened cranial base length, maxillary sagittal length and height, and bony pharynx depth. Patients with SMCP at age 9 to 11 years showed a smaller maxillary sagittal length and bony pharynx depth and an inharmonious jaw relationship. Patients with SMCP at age 18 to 30 years showed a smaller maxillary sagittal length and height and an inharmonious jaw relationship. CONCLUSIONS: SMCP is associated with progressive maxillary retrognathism and reduced profile convexity from childhood to adulthood.


Assuntos
Fissura Palatina/fisiopatologia , Maxila/crescimento & desenvolvimento , Desenvolvimento Maxilofacial/fisiologia , Faringe/crescimento & desenvolvimento , Retrognatismo/fisiopatologia , Base do Crânio/crescimento & desenvolvimento , Adolescente , Adulto , Fatores Etários , Cefalometria , Criança , Pré-Escolar , Fissura Palatina/diagnóstico por imagem , Estudos Transversais , Feminino , Humanos , Masculino , Maxila/anormalidades , Maxila/diagnóstico por imagem , Faringe/anormalidades , Faringe/diagnóstico por imagem , Retrognatismo/diagnóstico por imagem , Base do Crânio/anormalidades , Base do Crânio/diagnóstico por imagem
9.
Cleft Palate Craniofac J ; 55(10): 1367-1374, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29613840

RESUMO

OBJECTIVE: To identify the effects of palate repair on cranial base and maxillary morphology in patients with unilateral cleft lip and palate (UCLP) and to discover the relevance between cranial base and maxilla through cephalometric analysis. DESIGN: Retrospective. PATIENTS: Thirty-seven UCLP patients with operated lip (OL) and unoperated palate constituted OL group and were classified into 5 cervical vertebral maturation (CVM) stages. Thirty-seven UCLP patients with operated lip and palate (OLP) and 37 noncleft people with skeletal class I malocclusion were CVM- and sex-matched with the OL group as OLP group and control group, respectively. CVM stage I and II were combined into group 1, CVM stage III to V were combined into group 2. INTERVENTIONS: Lateral cephalograms of all participants were obtained. MAIN OUTCOME MEASURES: Cephalometric analysis was employed, and data were compared among groups. RESULTS: Length of posterior cranial base (Ba-S) of the OL group was shorter than controls in group 1; Ba-S and the ratio between length of posterior and anterior cranial base (Ba-S/S-N) of the OL and OLP groups were smaller than controls in group 2. No significant differences in cranial base were found between the OL and OLP groups. In group 1, patients of the OLP group showed smaller SNA, ANS-Ptm, and ANS-Ptm/S-N, and patients of the OL group showed smaller ANS-Ptm. In group 2, both OL and OLP groups had smaller sella-nasion-A point angle (SNA), projection distance between ANS and Ptm points on FH plane (ANS-Ptm), and the ratio between ANS-Ptm and anterior cranial base length (ANS-Ptm/S-N). CONCLUSIONS: Palate repair seems to have no obvious effects on cranial base morphology in patients with UCLP. Those patients with lip operated, whether cleft palate operated or not, tend to have a smaller length of maxilla sagittally and this deformity progresses with age.


Assuntos
Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Desenvolvimento Maxilofacial , Base do Crânio/crescimento & desenvolvimento , Adolescente , Cefalometria , Criança , China , Feminino , Humanos , Masculino , Estudos Retrospectivos , Base do Crânio/anormalidades , Adulto Jovem
10.
Angle Orthod ; 88(3): 283-291, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29337630

RESUMO

OBJECTIVES: To analyze differences in upper cervical spine and craniofacial morphology, including posterior cranial fossa and growth prediction signs, between Danish and South Korean pre-orthodontic skeletal Class II children and to analyze associations between upper cervical spine morphology and craniofacial characteristics. MATERIALS AND METHODS: One hundred forty-six skeletal Class II children-93 Danes (54 boys and 39 girls, mean age 12.2 years) and 53 Koreans (27 boys and 26 girls, mean age 10.8 years)-were included. Upper spine morphology, Atlas dimensions, and craniofacial morphology, including posterior cranial fossa and growth prediction signs, were assessed on lateral cephalograms. Differences and associations were analyzed by multiple linear and logistic regression analyses adjusted for age and gender. RESULTS: Significant differences between the ethnic groups were found in the sagittal and vertical craniofacial dimensions ( P < .001), mandibular shape ( P < .01), dental relationship ( P < .01), posterior cranial fossa ( P < .05), and growth prediction signs ( P < .001). No significant differences were found in upper spine morphology and Atlas dimensions between the groups. Upper spine morphology/dimensions were significantly associated with the cranial base angle ( P < .01), sagittal craniofacial dimensions ( P < .001), posterior cranial fossa ( P < .001), and growth prediction signs ( P < .05). CONCLUSIONS: Upper spine morphology/dimensions may be valuable as predictive factors in treatment planning for growing Class II children.


Assuntos
Grupo com Ancestrais do Continente Asiático/etnologia , Vértebras Cervicais/anatomia & histologia , Grupo com Ancestrais do Continente Europeu/etnologia , Ossos Faciais/anatomia & histologia , Má Oclusão de Angle Classe II/etnologia , Base do Crânio/anatomia & histologia , Cefalometria , Atlas Cervical/diagnóstico por imagem , Atlas Cervical/crescimento & desenvolvimento , Atlas Cervical/patologia , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/crescimento & desenvolvimento , Criança , Dinamarca , Ossos Faciais/diagnóstico por imagem , Ossos Faciais/crescimento & desenvolvimento , Feminino , Humanos , Masculino , Má Oclusão de Angle Classe II/diagnóstico por imagem , Má Oclusão de Angle Classe II/patologia , Radiografia , República da Coreia , Base do Crânio/diagnóstico por imagem , Base do Crânio/crescimento & desenvolvimento , Dimensão Vertical
11.
Pediatr Neurol ; 79: 3-7, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29290519

RESUMO

INTRODUCTION: The morphology of the skull base can be altered in craniosynostoses. The objective of this study is to evaluate the reduced intercarotid artery distance in the lacerum segment in patients with syndromic and isolated brachycephaly. MATERIALS AND METHODS: The distances between the inner walls of the carotid canal at the lacerum segment were measured on high-resolution CT scans in children with Crouzon (25), Pfeiffer (21), Apert (26), Saethre-Chotzen (7) syndromes, isolated bicoronal synostosis (9), and compared to an age-matched control group (30). RESULTS: A significantly smaller mean distance between carotid canal walls was observed in Crouzon (11.1 ± 4.9 mm), Pfeiffer (9.6 ± 5.1 mm), Apert (12.3 ± 4.3 mm), Saethre-Chotzen (14.8 ± 3.0 mm) syndromes, and isolated bicoronal synostosis (14.9 ± 3.7 mm) as compared to the control group (19.7 ± 2.4 mm, P < 0.001, P < 0.001, P < 0.001, P = 0.005, and P = 0.002, respectively). There was no statistically significant difference in intercarotid canal distance among the Apert, Saethre-Chotzen and isolated bicoronal synostosis groups. Overall, the brachycephalic group showed reduced intercarotid canal distance comparing to controls (P < 0.001). DISCUSSION AND CONCLUSIONS: There is significant reduction of the distance between carotid canals in brachycephalic patients. This distance is more significantly altered in FGFR-related brachycephaly syndromes (especially Crouzon and Pfeiffer syndromes), than Saethre-Chotzen syndrome (TWIST1 mutation) and isolated non-syndromic bicoronal synostosis. This study highlights the importance of FGFRs in shaping the skull base. Altered vascular course of the internal carotid arteries can have important implications in planning skull base surgery in brachycephalic patients.


Assuntos
Artérias Carótidas/patologia , Craniossinostoses/patologia , Adolescente , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/crescimento & desenvolvimento , Estudos de Casos e Controles , Criança , Pré-Escolar , Disostose Craniofacial/diagnóstico por imagem , Disostose Craniofacial/patologia , Disostose Craniofacial/cirurgia , Craniossinostoses/diagnóstico por imagem , Craniossinostoses/cirurgia , Feminino , Humanos , Lactente , Masculino , Tamanho do Órgão , Procedimentos Cirúrgicos Reconstrutivos , Estudos Retrospectivos , Base do Crânio/diagnóstico por imagem , Base do Crânio/crescimento & desenvolvimento , Base do Crânio/patologia , Tomografia Computadorizada por Raios X , Adulto Jovem
12.
Congenit Anom (Kyoto) ; 58(5): 158-166, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29322554

RESUMO

The cranial base is a structure mainly formed through endochondral ossification and integrated into the craniofacial complex, which acts as an underlying platform for the developing brain. Foxc1 is an indispensable regulator during intramembranous and endochondral ossification. In this study, we found that the spontaneous loss of Foxc1 function in a mouse (congenital hydrocephalous), Foxc1ch/ch , demonstrated the anterior cranial base defects, including unossified presphenoid and lack of middle part of the basisphenoid bone. Hypoplastic presphenoid primordial cartilage (basal portion of the trabecular cartilage [bTB]) and a lack of the middle part of basisphenoid primordial cartilage (the hypophyseal cartilage) were consistently observed at earlier developmental stage. Foxc1 was expressed robustly and ubiquitously in undifferentiated mesenchyme of the cranial base-forming area in E11.0 wild-type fetuses. Once chondrogenesis commenced, the expression was downregulated and later limited to the perichondrium. Detection of transcripts of Collagen type2 A1 (Col2a1) revealed that both bTB and the anterior part of the hypophyseal cartilage developing anterior to the persistent epithelial stalk of the anterior lobe of the pituitary gland were suppressed in the Foxc1ch/ch . Proliferation activity of chondrocyte precursor cells was higher in the Foxc1ch/ch . Loss of Foxc1 function only in the neural crest cell lineage (Wnt1-cre;Foxc1ch/flox ) showed ossification of the posterior part of the hypophyseal cartilage derived from the mesoderm. These findings suggest that Foxc1 is an important regulator to further chondrogenesis and initiate the ossification of the presphenoid and basisphenoid bones.


Assuntos
Colágeno Tipo II/genética , Fatores de Transcrição Forkhead/genética , Crista Neural/crescimento & desenvolvimento , Base do Crânio/crescimento & desenvolvimento , Animais , Condrócitos/metabolismo , Condrogênese/genética , Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Mesoderma/crescimento & desenvolvimento , Camundongos , Crista Neural/metabolismo , Base do Crânio/metabolismo
13.
Angle Orthod ; 87(6): 897-910, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28737426

RESUMO

OBJECTIVE: To provide a synthesis of the published studies evaluating the natural growth and development of the human posterior cranial base (S-Ba). MATERIALS AND METHODS: The search was performed on MEDLINE, Embase, PubMed, and all EBM Reviews electronic databases. In addition, reference lists of the included studies were hand-searched. Articles were included if they analyzed posterior cranial-base growth in humans specifically. Study selection, data extraction, and risk of bias assessment were completed in duplicate. A meta-analysis was not justified. RESULTS: Finally, 23 published studies were selected: 5 cross-sectional and 18 cohort studies. Articles were published between 1955 and 2015, and all were published in English. The sample sizes varied between 20 and 397 individuals and consisted of craniofacial measurements from either living or deceased human skulls. Validity of the measurements was not determined in any of the studies, while six papers reported some form of reliability assessment. All the articles included multiple time points within the same population or data from multiple age groups. Growth of S-Ba was generally agreed to be from spheno-occipital synchondrosis growth. Basion displaced downward and backward and sella turcica moved downward and backward during craniofacial growth. Timing of cessation of S-Ba growth was not conclusive due to limited identified evidence. CONCLUSIONS: Current evidence suggests that S-Ba is not totally stable, as its dimensions change throughout craniofacial growth and a minor dimensional change is observed even in late adulthood.


Assuntos
Base do Crânio/crescimento & desenvolvimento , Humanos
14.
Orthod Craniofac Res ; 20 Suppl 1: 18-25, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28643912

RESUMO

The cranial base is a central and integral component of the cranioskeleton, yet little is known about its growth. Despite the dissimilarities between human and murine cranioskeletal form, mouse models are proving instrumental in studying craniofacial growth. The objectives of this review are to summarize recent findings from numerous mouse models that display growth defects in one or more cranial base synchondroses, with accompanying changes in chondrocyte cellular zones. Many of these models also display altered growth of the cranial vault and/or the facial region. FGFR, PTHrP, Ihh, BMP and Wnt/ß-catenin, as well as components of primary cilia, are the major genes and signalling pathways identified in cranial base synchondroses. Together, these models are helping to uncover specific genetic influences and signalling pathways operational at the cranial base synchondroses. Many of these genes are in common with those of importance in the cranial vault and the facial skeleton, emphasizing the molecular integration of growth between the cranial base and other cranial regions. Selected models are also being utilized in testing therapeutic agents to correct defective craniofacial and cranial base growth.


Assuntos
Base do Crânio/anormalidades , Base do Crânio/crescimento & desenvolvimento , Animais , Regulação da Expressão Gênica no Desenvolvimento , Desenvolvimento Maxilofacial/genética , Desenvolvimento Maxilofacial/fisiologia , Camundongos , Modelos Animais
15.
Calcif Tissue Int ; 101(3): 300-311, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28391432

RESUMO

Thyroid hormone is important for skull bone growth, which primarily occurs at the cranial sutures and synchondroses. Thyroid hormones regulate metabolism and act in all stages of cartilage and bone development and maintenance by interacting with growth hormone and regulating insulin-like growth factor. Aberrant thyroid hormone levels and exposure during development are exogenous factors that may exacerbate susceptibility to craniofacial abnormalities potentially through changes in growth at the synchondroses of the cranial base. To elucidate the direct effect of in utero therapeutic thyroxine exposure on the synchondroses in developing mice, we provided scaled doses of the thyroid replacement drug, levothyroxine, in drinking water to pregnant C57BL6 wild-type dams. The skulls of resulting pups were subjected to micro-computed tomography analysis revealing less bone volume relative to tissue volume in the synchondroses of mouse pups exposed in utero to levothyroxine. Histological assessment of the cranial base area indicated more active synchondroses as measured by metabolic factors including Igf1. The cranial base of the pups exposed to high levels of levothyroxine also contained more collagen fiber matrix and an increase in markers of bone formation. Such changes due to exposure to exogenous thyroid hormone may drive overall morphological changes. Thus, excess thyroid hormone exposure to the fetus during pregnancy may lead to altered craniofacial growth and increased risk of anomalies in offspring.


Assuntos
Efeitos Tardios da Exposição Pré-Natal/patologia , Base do Crânio/efeitos dos fármacos , Base do Crânio/crescimento & desenvolvimento , Tiroxina/toxicidade , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Hormônios Tireóideos/toxicidade , Microtomografia por Raio-X
16.
Am J Orthod Dentofacial Orthop ; 151(2): 342-350.e2, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28153164

RESUMO

INTRODUCTION: Initially, cone-beam computed tomography images from dry skulls were used to 3 dimensionally evaluate intrarater and interrater reliabilities and accuracy of selected 3-dimensional landmarks located in the anterior and middle cranial bases. Thereafter, dimensional changes of the anterior and middle cranial bases with growth were evaluated by using the previously selected landmarks. METHODS: Cone-beam computed tomography images of 10 dry skulls were used to identify useful landmarks from different areas of the anterior and middle cranial bases based on their reliability and accuracy. These selected landmarks were identified in the images of an already available sample of adolescents (n = 60) taken at 2 time points (19 months apart) to assess dimensional changes with growth. RESULTS: The majority of the proposed 3-dimensional landmarks with the exception of the lesser wing of the sphenoid showed acceptable intrarater and interrater reliabilities. The distances measured between foramina and canals in the transverse dimension showed evidence of increases in size. However, the mean amounts of increase in these transverse distances were equal to or less than 1.05 mm (from 1.1% to 4.1%). No change was observed between the right and left anterior and posterior clinoid processes. The vertical dimensions showed evidence of some changes, but these were within 2% of the original distances. CONCLUSIONS: In this adolescent sample, minor growth-related changes were observed in the anterior and middle cranial bases. The midsagittal area of the anterior cranial base (foramen caecum to presphenoid) was stable. The right and left anterior and posterior clinoid processes can be used for transverse superimposition.


Assuntos
Pontos de Referência Anatômicos/diagnóstico por imagem , Pontos de Referência Anatômicos/crescimento & desenvolvimento , Tomografia Computadorizada de Feixe Cônico , Imageamento Tridimensional , Base do Crânio/diagnóstico por imagem , Base do Crânio/crescimento & desenvolvimento , Adolescente , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino , Estudos Retrospectivos
17.
Bone ; 101: 179-190, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27170093

RESUMO

Bardet-Biedl Syndrome (BBS) is an autosomal recessive disorder and is classified as one of the ciliopathy. The patients manifest a characteristic craniofacial dysmorphology but the effects of Bbs3 deficiency in the developmental process during the craniofacial pathogenesis are still incompletely understood. Here, we analyzed a cranial development of a BBS model Bbs3-/- mouse. It was previously reported that these mutant mice exhibit a dome-shape cranium. We show that Bbs3-/- mouse embryos present mid-facial hypoplasia and solitary central upper incisor. Morphologically, these mutant mice show synchondrosis of the cranial base midline due to the failure to fuse in association with loss of intrasphenoidal synchondrosis. The cranial base was laterally expanded and longitudinally shortened. In the developing cartilaginous primordium of cranial base, cells present in the midline were less in Bbs3-/- embryos. Expression of BBS3 was observed specifically in a cell population lying between condensed ectomesenchyme in the midline and the ventral midbrain at this stage. Finally, siRNA-based knockdown of Bbs3 in ATDC5 cells impaired migration in culture. Our data suggest that BBS3 is required for the development of cranial base via regulation of cell migration toward the midline where they promote the condensation of ectomesenchyme and form the future cartilaginous templates of cranial base.


Assuntos
Fatores de Ribosilação do ADP/metabolismo , Síndrome de Bardet-Biedl/metabolismo , Base do Crânio/crescimento & desenvolvimento , Base do Crânio/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Fatores de Ribosilação do ADP/genética , Animais , Síndrome de Bardet-Biedl/genética , Feminino , Imunofluorescência , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação/genética , Fenótipo , Microtomografia por Raio-X , Peixe-Zebra , Proteínas de Peixe-Zebra/genética
18.
Eur J Paediatr Dent ; 17(3): 213-219, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27759410

RESUMO

AIM: The reported effects of Bionator treatment in patients with mandibular retrognathism are conflicting. This study evaluated the changes in craniofacial morphology resulting from treatment with a Bionator, based on measurement percentiles previously reported, to clarify the mechanism of the effect of this commonly used functional device. MATERIALS AND METHODS: Study Design: Retrospective. SETTING: A private orthodontic clinic. PARTICIPANTS: Forty-two children (mean age, 10.13 years) requiring treatment with a Bionator for Class II malocclusion (mandibular retrognathism). Children were randomly assigned to a Bionator group with or without an expansion screw. Measurements on lateral cephalometric radiographs were taken before and upon completion of Bionator treatment. All parameters measured were characterised according to the measurement percentiles previously reported. Each parameter was compared before and after treatment for all patients and for each treatment group using Wilcoxon's test. RESULTS: No significant differences in cranial length or mandibular body length were seen in any of the 3 groups, but anterior cranial base length and maxillary length were significantly decreased while mandibular ramus height and mandibular length were significantly increased after treatment in the Bionator with expansion screw group and in the all-patient group. CONCLUSIONS: The findings suggest that treatment with a Bionator with expansion screw during the growth and development stage results in increased mandible length and ramus height and inhibits the growth of the maxilla and anterior cranial base bone.


Assuntos
Aparelhos Ativadores , Má Oclusão de Angle Classe II/terapia , Desenho de Aparelho Ortodôntico , Retrognatismo/terapia , Adolescente , Pontos de Referência Anatômicos/crescimento & desenvolvimento , Pontos de Referência Anatômicos/patologia , Cefalometria/métodos , Criança , Feminino , Seguimentos , Humanos , Masculino , Mandíbula/crescimento & desenvolvimento , Mandíbula/patologia , Côndilo Mandibular/crescimento & desenvolvimento , Côndilo Mandibular/patologia , Maxila/crescimento & desenvolvimento , Maxila/patologia , Osso Nasal/patologia , Fossa Pterigopalatina/patologia , Estudos Retrospectivos , Sela Túrcica/patologia , Base do Crânio/crescimento & desenvolvimento , Base do Crânio/patologia
19.
Orthod Craniofac Res ; 19(4): 222-233, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27506322

RESUMO

OBJECTIVES: There is controversy regarding the relationship between mandibular position and alterations of the cranial base that provoke a more anterior location of the glenoid fossa. Artificially deformed skulls display marked alterations of the cranial base. This study evaluates mandibular changes as function of the morphology of the cranial base in these skulls. MATERIAL AND METHODS: A geometric morphometric study was performed on lateral cephalometric X-rays of three groups of skulls: 32 with anteroposterior deformity, 17 with circumferential deformity and 39 with no apparent deformity. RESULTS: In artificially deformed skulls, the cranial base was deformed causing the mandibular condyle to be in a more anterior position. There was a complete remodelling of the mandible involving narrowing and elongation of the mandibular ramus, rotation of the corpus of the mandible and increased vertical height of the symphysis. Forward displacement did not occur. Integration between mandible and cranial base is not altered by deformation of the skull. CONCLUSIONS: Deformity of the cranial vault exerts an influence on the mandible, supporting the theory of modular units in complete integration. This also supports the theory that mandibular prognathism is a multifactorial result and not a direct effect of displacement of the cranial base.


Assuntos
Cefalometria/métodos , Anormalidades Craniofaciais/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Mandíbula/patologia , Base do Crânio/patologia , Crânio/diagnóstico por imagem , Crânio/patologia , Arqueologia , Anormalidades Craniofaciais/etnologia , Anormalidades Craniofaciais/etiologia , História Antiga , Humanos , Índios Sul-Americanos/etnologia , Masculino , Mandíbula/crescimento & desenvolvimento , Côndilo Mandibular/patologia , Peru/etnologia , Análise de Componente Principal , Prognatismo/etiologia , Radiografia/métodos , Crânio/crescimento & desenvolvimento , Base do Crânio/crescimento & desenvolvimento
20.
Neurosurgery ; 79(5): 722-735, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27341342

RESUMO

BACKGROUND: To date, no study has compared the evolution of the foramen magnum area (FMA) and the posterior cranial fossa volume (PCFV) with the degree of cranial base synchondrosis ossification. OBJECTIVE: To illustrate these features in healthy children. METHODS: The FMA, the PCFV, and the ossification of 12 synchondroses according to the Madeline and Elster scale were retrospectively analyzed in 235 healthy children using millimeter slices on a computed tomography scan. RESULTS: The mean FMA of 6.49 cm in girls was significantly inferior to the FMA of 7.67 cm in boys (P < .001). In both sexes, the growth evolved in a 2-phase process, with a phase of rapid growth from birth to 3.75 years old (yo) followed by a phase of stabilization. In girls, the first phase was shorter (ending at 2.6 yo) than in boys (ending at 4.33 yo) and proceeded at a higher rate. PCFV was smaller in girls (P < .001) and displayed a biphasic pattern in the whole population, with a phase of rapid growth from birth to 3.58 yo followed by a phase of slow growth until 16 yo. In girls, the first phase was more active and shorter (ending at 2.67 yo) than in boys (ending at 4.5 yo). The posterior interoccipital synchondroses close first, followed by the anterior interoccipital and occipitomastoidal synchondroses, the lambdoid sutures simultaneously, then the petro-occipital and spheno-occipital synchondroses simultaneously. CONCLUSION: The data provide a chronology of synchondrosis closure. We showed that FMA and PCFV are constitutionally smaller in girls at birth (P ≤ .02) and suggest that a sex-related difference in the FMA is related to earlier closure of anterior interoccipital synchondroses in girls (P = .01). ABBREVIATIONS: AIOS, anterior interoccipital synchondrosesFMA, foramen magnum areaLS, lambdoid suturesOMS, occipitomastoidal synchondrosesPCFV, posterior cranial fossa volumePIOS, posterior interoccipital synchondrosesPOS, petro-occipital synchondrosesSOS, spheno-occipital synchondrosisyo, years old.


Assuntos
Desenvolvimento Infantil , Fossa Craniana Posterior/crescimento & desenvolvimento , Suturas Cranianas/crescimento & desenvolvimento , Forame Magno/crescimento & desenvolvimento , Osteogênese , Base do Crânio/crescimento & desenvolvimento , Adolescente , Criança , Pré-Escolar , Fossa Craniana Posterior/diagnóstico por imagem , Suturas Cranianas/diagnóstico por imagem , Feminino , Forame Magno/diagnóstico por imagem , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Caracteres Sexuais , Base do Crânio/diagnóstico por imagem , Tomografia Computadorizada por Raios X
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