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1.
Microsc Res Tech ; 86(12): 1568-1582, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37493098

RESUMO

This study compares the skeletal calcification pattern of batoid Raja asterias with the endochondral ossification model of mammalians Homo sapiens and teleost Xiphias gladius. Skeletal mineralization serves to stiffen the mobile elements for locomotion. Histology, histochemistry, heat deproteination, scanning electron microscopy (SEM)/EDAX analysis, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and Fourier transform infrared spectrometry (FTIR) have been applied in the study. H. sapiens and X. gladius bone specimens showed similar profiles, R. asterias calcified cartilage diverges for higher water release and more amorphous bioapatite. In endochondral ossification, fetal calcified cartilage is progressively replaced by bone matrix, while R. asterias calcified cartilage remains un-remodeled throughout the life span. Ca2+ and PO4 3- concentration in extracellular matrix is suggested to reach the critical salts precipitation point through H2 O recall from extracellular matrix into both chondroblasts or osteoblasts. Cartilage organic phase layout and incomplete mineralization allow interstitial fluids diffusion, chondrocytes survival, and growth in a calcified tissue lacking of a vascular and canalicular system. HIGHLIGHTS: Comparative physico-chemical characterization (TGA, DTG and DSC) testifies the mass loss due to water release, collagen and carbonate decomposition of the three tested matrices. R. asterias calcified cartilage water content is higher than that of H. sapiens and X. gladius, as shown by the respectively highest dehydration enthalpy values. Lower crystallinity degree of R. asterias calcified cartilage can be related to the higher amount of collagen in amorphous form than in bone matrix. These data can be discussed in terms of the mechanostat theory (Frost, 1966) or by organic/inorganic phase transformation in the course evolution from fin to limbs. Mineral analysis documented different charactersof R. asterias vs H. sapiens and X. gladius calcified matrix.


Assuntos
Matriz Óssea , Calcinose , Humanos , Animais , Cartilagem , Colágeno/análise , Água/análise , Calcificação Fisiológica , Mamíferos
2.
J Anat ; 243(4): 605-617, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37125509

RESUMO

The macroscopic and microscopic morphology of the appendicular skeleton was studied in the two species Raja asterias (order Rajiformes) and Torpedo marmorata (Order Torpediniformes), comparing the organization and structural layout of pectoral, pelvic, and tail fin systems. The shape, surface area and portance of the T. marmorata pectoral fin system (hydrodynamic lift) were conditioned by the presence of the two electric organs in the disk central part, which reduced the pectoral fin surface area, suggesting a lower efficiency of the "flapping effectors" than those of R. asterias. Otherwise, radials' rays alignment, morphology and calcification pattern showed in both species the same structural layout characterized in the fin medial zone by stiffly paired columns of calcified tiles in the perpendicular plane to the flat batoid body, then revolving and in the horizontal plane to continue as separate mono-columnar rays in the fin lateral zone with a morphology suggesting fin stiffness variance between medial/lateral zone. Pelvic fins morphology was alike in the two species, however with different calcified tiles patterns of the 1st compound radial and pterygia in respect to the fin-rays articulating perpendicularly to the latter, whose tile rows lay-out was also different from that of the pectoral fins radials. The T. marmorata tail-caudal fin showed a muscular and connective scaffold capable of a significant oscillatory forward thrust. On the contrary, the R. asterias dorsal tail fins were stiffened by a scaffold of radials-like calcified segments. Histomorphology, heat-deproteination technique and morphometry provided new data on the wing-fins structural layout which can be correlated to the mechanics of the Batoid swimming behavior and suggested a cartilage-calcification process combining interstitial cartilage growth (as that of all vertebrates anlagen) and a mineral deposition with accretion of individual centers (the tiles). The resulting layout showed scattered zones of un-mineralized matrix within the calcified mass and a less compact texture of the matrix calcified fibers suggesting a possible way of fluid diffusion throughout the mineralized tissue. These observations could explain the survival of the embedded chondrocytes in absence of a canalicular system as that of the cortical bone.


Assuntos
Asterias , Rajidae , Animais , Rajidae/anatomia & histologia , Natação , Torpedo , Nadadeiras de Animais/anatomia & histologia , Anatomia Comparada , Locomoção , Fenômenos Biomecânicos
3.
Children (Basel) ; 8(1)2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33440762

RESUMO

(1) Background: To investigate condylar position in subjects with functional posterior crossbite comparing findings before and after rapid maxillary expansion (RME) treatment through 3D analysis; (2) Methods: Thirty-two Caucasian patients (14 males, mean age 8 y 8 m ± 1 y 2 m; 18 females mean age 8 y 2 m ± 1 y 4 m) with functional posterior crossbite (FPXB) diagnosis underwent rapid palatal expansion with a Haas appliance banded on second deciduous upper molars. Patients' underwent CBCT scans before rapid palatal expansion (T0) and after 12 months (T1). The images were processed through 3D slicer software; (3) Results: The condylar position changes between T1 and T0 among the crossbite and non-crossbite sides were not statistically significant, except for the transversal axis. At T1, the condyles moved forward (y axis) and laterally (x axis), they also moved downward (z axis) but not significantly; (4) Conclusions: Condilar position in growing patients with functional posterior crossbite did not change significantly after rapid maxillary expansion.

4.
Minerva Pediatr ; 71(4): 380-389, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30511557

RESUMO

INTRODUCTION: Growth retardation was frequently observed in obstructive sleep apnea (OSA) patients but the complex mechanisms causing this condition are still unclear. Several findings suggested growth catch-up after surgical treatment but other studies did not confirm the results, showing no improvement in OSA patients after tonsillectomy and adenoidectomy (T&A). The aim of the present study was to systematically review scientific literature of the relationships between OSA and metabolic changes involving growth hormone (GH) axis before and after treatment in patients. EVIDENCE ACQUISITION: Different databases were searched without limitations up to August 2017. Additionally, the bibliographies of the finally selected articles were hand searched to identify any relevant publications that were not previously identified. EVIDENCE SYNTHESIS: From the 37 studies collected from all the databases based on their title and abstract, only 12 studies actually fulfilled the selection criteria. From the twelve finally selected articles, eight focused on growth mediators, two evaluated endothelial mediators, one focused on neurocognitive function and mediators and one focused on local inflammation. CONCLUSIONS: OSA children present lower levels of growth mediators (IGF-I and IGFBP-3) thus indicating growth retardation, significantly higher cardiovascular disease risk and decreased cognitive functions when compared to controls. T&A seems to improve all the above mentioned functions with great impact on general health.


Assuntos
Transtornos do Crescimento/etiologia , Hormônio do Crescimento Humano/metabolismo , Apneia Obstrutiva do Sono/complicações , Adenoidectomia/métodos , Criança , Transtornos do Crescimento/epidemiologia , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Apneia Obstrutiva do Sono/cirurgia , Tonsilectomia/métodos
5.
Minerva Stomatol ; 67(4): 165-171, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29527867

RESUMO

BACKGROUND: Moebius syndrome is a rare condition characterized by bilateral facial and abducens nerve paralysis. The aim of this study is to evaluate the main orthodontic features and the frequency of associated clinical characteristics in patients with Moebius syndrome (MS). METHODS: According to Terzis classifications, 58 patients with MS aged 8 months to 46 years old underwent orthodontics and clinical examination. RESULTS: Strabismus, upper and lower limb malformations, lip and palatal cleft were frequently associated with MS. Reduced TM movements were noted (48%). Cephalometric analysis did not allow identifying a typical facies and a characteristic cephalometric pattern; we have noticed a higher prevalence of Class II (56%) with micrognathia and excessive maxillary development probably due to the lack of lip seal. Early treatment is recommended, with a multidisciplinary approach to reduce the impact of sequelae on the lives of MS patients or their families. CONCLUSIONS: Early treatment is recommended, with a multidisciplinary approach to diminish the impact of sequelae on the lives of MS patients or their families.


Assuntos
Má Oclusão Classe II de Angle/terapia , Micrognatismo/terapia , Síndrome de Möbius/patologia , Ortodontia Corretiva/métodos , Adolescente , Adulto , Cefalometria , Criança , Pré-Escolar , Fenda Labial , Fissura Palatina , Diagnóstico Bucal , Feminino , Humanos , Lactente , Deformidades Congênitas dos Membros , Masculino , Má Oclusão Classe II de Angle/etiologia , Micrognatismo/etiologia , Pessoa de Meia-Idade , Síndrome de Möbius/embriologia , Síndrome de Möbius/genética , Cooperação do Paciente , Fenótipo , Estrabismo , Adulto Jovem
6.
J Periodontol ; 86(2): 192-200, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25272979

RESUMO

BACKGROUND: Only a few studies have dealt with immediately loaded, unsplinted mini-implants supporting ball attachment-retained mandibular overdentures (ODs). The aim of this study is to evaluate treatment outcomes of ball attachment-retained mandibular ODs supported by one-piece, unsplinted, immediately loaded, direct metal laser sintering (DMLS) mini-implants. METHODS: Over a 4-year period (2009 to 2012), all patients referred to the Dental Clinic, University of Varese, and to a private practice for treatment with mandibular ODs were considered for inclusion in this study. Each patient received three or four DMLS mini-implants. Immediately after implant placement, a mandibular OD was connected to the implants. At each annual follow-up session, clinical and radiographic parameters were assessed, including the following outcome measures: 1) implant failures; 2) peri-implant marginal bone loss; and 3) complications. Statistical analysis was conducted using a life-table analysis. RESULTS: A total of 231 one-piece DMLS mini-implants were inserted in 62 patients. After 4 years of loading, six implants failed, giving an overall cumulative survival rate of 96.9%. The mean distance between the implant shoulder and the first visible bone-to-implant contact was 0.38 ± 0.25 and 0.62 ± 0.20 mm at the 1- and 4-year follow-up examinations, respectively. An incidence of 6.0% of biologic complications was reported; prosthetic complications were more frequent (12.9%). CONCLUSIONS: Within the limits of this study, it can be concluded that the immediate loading of one-piece, unsplinted, DMLS titanium mini-implants by means of ball attachment-supported mandibular ODs is a successful treatment procedure. Long-term follow-up studies are needed to confirm these results.


Assuntos
Implantes Dentários , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Prótese Total Inferior , Revestimento de Dentadura , Carga Imediata em Implante Dentário/métodos , Lasers , Idoso , Idoso de 80 Anos ou mais , Ligas , Perda do Osso Alveolar/classificação , Desenho Assistido por Computador , Ligas Dentárias/química , Falha de Restauração Dentária , Retenção de Dentadura/instrumentação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Miniaturização , Peri-Implantite/classificação , Estudos Prospectivos , Radiografia Interproximal/métodos , Estomatite/classificação , Análise de Sobrevida , Titânio/química , Resultado do Tratamento
7.
Implant Dent ; 22(4): 388-93, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23823735

RESUMO

PURPOSE: Selective laser sintering (SLS) is a new technique that allows implants to be produced by annealing titanium powder microparticles in a focused laser beam, according to a computer-generated model. The aim of this study was to evaluate the survival and success rate of immediately restored 1-piece narrow-diameter SLS implants, placed in the posterior jaws, after 2 years of functional loading. MATERIALS AND METHODS: At the 2-year follow-up examination, several parameters were assessed. Success criteria included absence of pain, suppuration, exudation, implant mobility; distance between the implant shoulder and the first visible bone-to-implant contact <2.0 mm; and absence of prosthetic complications. RESULTS: Thirty-seven implants were placed in the posterior jaws (14 maxilla, 23 mandible) of 16 patients (9 males, 7 females). The prosthetic restorations comprised 16 immediately restored fixed partial prostheses. No implant failure occurred, resulting in a 100% survival rate. The implant success was 94.6%, and the mean distance between the implant shoulder and the first visible bone-to-implant contact (DIB) was 0.4 ± 0.3 mm. CONCLUSIONS: This study supports the hypothesis that 1-piece narrow-diameter SLS implants can be used in fixed prosthetic rehabilitations in the posterior regions of both jaws with a predictable positive outcome.


Assuntos
Corrosão Dentária/métodos , Implantes Dentários , Prótese Dentária Fixada por Implante , Prótese Parcial Fixa , Carga Imediata em Implante Dentário/métodos , Lasers , Idoso , Ligas , Ligas Dentárias/química , Arco Dental/cirurgia , Planejamento de Prótese Dentária , Retenção em Prótese Dentária , Feminino , Seguimentos , Humanos , Masculino , Mandíbula/cirurgia , Maxila/cirurgia , Pessoa de Meia-Idade , Osseointegração/fisiologia , Medição da Dor , Estudos Prospectivos , Supuração , Propriedades de Superfície , Cirurgia Assistida por Computador , Análise de Sobrevida , Titânio/química , Resultado do Tratamento
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