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1.
Polymers (Basel) ; 14(18)2022 Sep 08.
Article in English | MEDLINE | ID: mdl-36145894

ABSTRACT

Curaua, as a leaf-based natural fiber, appears to be a promising component with aramid fabric reinforcement of hybrid composites. This work deals with the investigation of flexural, impact and elastic properties of non-woven curaua-aramid fabric hybrid epoxy composites. Five configurations of hybrid composites in a curaua non-woven mat with an increasing quantity of layers, up to four layers, were laminated through the conventional hand lay-up method. The proposed configurations were idealized with at least 60 wt% reinforcement in the non-alternating configuration. As a result, it was observed that the flexural strength decreased by 33% and the flexural modulus by 56%. In addition, the energy absorbed in the Charpy impact also decreased in the same proportion as the replaced amount of aramid. Through the impulse excitation technique, it was possible observe that the replacement of the aramid layers with the curaua layers resulted in decreased elastic properties. However, reduction maps revealed proportional advantages in hybridizing the curaua with the aramid fiber. Moreover, the hybrid composite produced an almost continuous and homogeneous material, reducing the possibility of delamination and transverse deformation, which revealed an impact-resistant performance.

2.
Am J Orthod Dentofacial Orthop ; 159(1): 71-80, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33234461

ABSTRACT

INTRODUCTION: Surgically assisted rapid maxillary expansion is a widely used surgical procedure for resolving transverse maxillary occlusal changes in patients with bone maturity. However, few studies about the postoperative morphologic alterations in the nasal cavity in its inferior portion and the nasal septum positioning exist. METHODS: The linear nasal septum measurements of 26 adult patients treated with surgically assisted rapid maxillary expansion from 2009 to 2013 were assessed through a retrospective analysis of cone-beam computed tomographies, in Digital Imaging and Communications in Medicine files, through the Dolphin Imaging program (Dolphin Imaging and Management Solutions, Chatsworth, Calif), aimed to identify significant changes during 3 time periods of the treatment: preoperative, immediately after the palatal expansion device locking (immediate postoperative), and 6-months postoperative (late postoperative). The analyses were performed in the inferior third of the nasal septum, from 4 equidistant points in anteroposterior position and height, using fixed cranial references for lateral measures of displacement. RESULTS: No significant difference was found between preoperative, immediate postoperative, and late postoperative measurements in the 4 fixed nasal septum measurements, applying the analysis of variance test with a significance level of 5%. Comparing the surgical times alone, we found no statistically significant difference between the right and left sides applying the Student t test, which also showed symmetry in the nasal septum. CONCLUSIONS: The measurements of the nasal septum did not change in the different surgical times throughout their inferior extension, and they remained symmetrical throughout patients' follow-up period.


Subject(s)
Nasal Septum , Palatal Expansion Technique , Adult , Cone-Beam Computed Tomography , Humans , Maxilla , Nasal Cavity , Nasal Septum/diagnostic imaging , Nasal Septum/surgery , Retrospective Studies
3.
J Biomater Appl ; 29(7): 1003-13, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25245781

ABSTRACT

We evaluated histologically, histomorphometrically, and tomographically the effects of the association of fresh-frozen bone allograft (FFB) with bovine bone mineral (BBM) in maxillary sinus floor augmentation. In total, 34 maxillary sinuses from 29 patients, with a mean age of 51.32 (±6.44) years, underwent sinus augmentation. Patients were divided into control and test groups (17 sinuses each). The controls were grafted with allograft bone, and the test group received a combination of FFB and BBM at a 2:1 ratio. After 6 months, bone samples were collected for histological and histomorphometric examinations. The implant survival rates were 93.02% (control group) and 100% (test group) at 6 months after functional loading. Median volumetric reductions of 28.32% (17.05-44.05) and 12.62% (5.65-16.87) were observed for the control and test groups, respectively. Statistically significant histomorphometric differences were found between the control and test groups regarding newly formed bone 12.54% (10.50-13.33) vs. 24.42% (17.62-35.92), p < 0.001, total bone 48.34% (39.03-54.42) vs. 61.32% (50.61-64.96), p = 0.007, and connective tissue 51.66% (45.57-60.97) vs. 39.30% (35.03-49.37), p = 0.007. The addition of BBM to allograft bone in maxillary sinus augmentation resulted in higher percentages of new bone formation and total bone, and permitted implant placement with a low rate of osseointegration failure at the 6-month follow-up.


Subject(s)
Bone Transplantation/methods , Minerals/administration & dosage , Sinus Floor Augmentation/methods , Adult , Allografts , Animals , Biocompatible Materials , Bone Regeneration , Cattle , Female , Humans , Male , Materials Testing , Middle Aged , Osteogenesis , Prospective Studies
5.
J Craniofac Surg ; 22(6): 2205-7, 2011 Nov.
Article in English | MEDLINE | ID: mdl-22075823

ABSTRACT

Defects on the craniofacial complex may result in aesthetic defects, functional damage, and psychologic consequences. Previously, surgeons showed no interest in reconstructing the operated area, but in the treatment of the problem, leaving bone contour is a secondary issue. Nowadays, area reconstruction with post-reestablishment of contour and local shape has become one of the surgeon's priorities. The use of alloplastic implants with specific digital design has been stated to be an effective technique on the treatment of craniofacial defects, reducing the need for manipulation in the intraoperative period and decreasing surgery time. Polyether ether ketone (PEEK) is a potential candidate because it is a linear polyaromatic semicrystalline polymer that combines strength, stiffness, durability, and resistance. Polyether ether ketone biocompatibility has been supported in literature, and subsequent medical applications of the material have been observed. The aim of this study was to describe a case of frontal bone defect reconstruction in which the PEEK was used as polymer material in a specific implant for the Synthes (PEEK-PSI) patient.


Subject(s)
Frontal Bone/injuries , Frontal Bone/surgery , Plastic Surgery Procedures/methods , Prostheses and Implants , Skull Fractures/surgery , Benzophenones , Esthetics , Frontal Bone/diagnostic imaging , Humans , Ketones , Male , Middle Aged , Polyethylene Glycols , Polymers , Skull Fractures/etiology , Tomography, X-Ray Computed , Violence
6.
Rev. cir. traumatol. buco-maxilo-fac ; 11(3): 33-38, Jul.-Set. 2011. ilus
Article in Portuguese | LILACS | ID: lil-792205

ABSTRACT

A anestesia local é fundamental no controle da dor em procedimentos odontológicos, porém a maioria das emergências ambulatoriais ocorrem durante ou imediatamente após a injeção do anestésico local. Dentre estes, podemos citar a fratura da agulha, que, apesar de incomum, pode ocorrer devido a uma técnica anestésica equivocada, ao uso de material de baixa qualidade ou à falta de colaboração do paciente. Após a fratura, o fragmento pode se mover através dos tecidos, necessitando de uma avaliação cuidadosa de um cirurgião buco-maxilo-facial antes da tentativa de recuperação desta. Várias técnicas de localização são descritas na literatura, como a tomografia computadorizada, panorâmica, detectores de metais, as radiografias convencionais e fluoroscopia transoperatória. O objetivo deste trabalho é apresentar uma breve revisão de literatura e relatar um caso de fratura de agulha em que a utilização da tomografia computadorizada de feixe cônico como um exame pré-operatório foi associada com fluoroscopia transoperatória para identificação e retirada de corpo estranho.


Local anesthesia is fundamental in pain control in dental procedures. Most emergencies in outpatient departments, however, occur during or immediately after the injection of local anesthetic. Among these we may mention needle fracture which, although uncommon, can occur because of an erroneous anesthetic technique, use of low-grade material or lack of cooperation on the part of the patient. After fracture, the fragment may move through the tissues, requiring careful evaluation by a maxillofacial surgeon before an attempt is made to recover it. Several location techniques are described in the literature, such as panoramic, computed tomography, metal detectors, conventional radiographs and intraoperative fluoroscopy. The aim of the present study is to review the literature and report a case of needle fracture in which the use of cone beam computed tomography as a preoperative examination was associated with fluoroscopy, perioperatively, for identification and removal of any foreign bodies.

7.
Rev. odontol. UNESP (Online) ; 40(4): 195-198, jul.-ago. 2011. ilus
Article in Portuguese | LILACS, BBO - Dentistry | ID: lil-614427

ABSTRACT

Comunicações ou fístulas bucossinusais são espaços patológicos criados entre o seio maxilar e a cavidade bucal, geralmente associadas a exodontias em região posterior de maxila. A literatura cita inúmeros fatores etiológicos e métodos de fechamento, que dependem do bom diagnóstico e de indicação adequada, variando tais comunicaçõesem relação a tamanho, duração, associação com patologias sinusais e localização. O objetivo do presente artigo é relatar uma comunicação bucossinusal de difícil diagnóstico, através do ligamento periodontal do primeiro molar, após tentativas de enxerto gengival no local.


Communications or oroantral fistulas are pathological spaces created between maxillary sinus and the oral cavity, which are usually associated with tooth extraction in the area of posterior maxilla. The literature suggests several etiological factors and of hard diagnosis through the first molar periodontal ligament, after attempts of methods torepair it, that rely on an appropriate diagnosis and indication. Change according to the size, duration and association with sinus conditions and location. The purpose of this current report is to relate an oroantral communication gingival graft in the affected site.


Subject(s)
Humans , Male , Adult , Periodontal Ligament , Surgery, Oral , Oroantral Fistula , Maxillary Sinus , Molar
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