Influence of Pigment and Opacifier on Dimensional Stability and Detail Reproduction of Maxillofacial Silicone Elastomer

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of opacifiers on dimensional stability and detail reproduction of maxillofacial silicone elastomer

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Color stability of maxillofacial silicone with nanoparticle pigment and opacifier submitted to disinfection and artificial aging

The purpose of this study was to evaluate the color stability of a maxillofacial elastomer with the addition of a nanoparticle pigment and/or an opacifier submitted to chemical disinfection and artificial aging. Specimens were divided into four groups (n = 30): group I: silicone without pigment or opacifier, group II: ceramic powder pigment, group III: Barium sulfate (BaSO(4)) opacifier, and group IV: ceramic powder and BaSO(4) opacifier. Specimens of each group (n = 10) were disinfected with effervescent tablets, neutral soap, or 4% chlorhexidine gluconate. Disinfection was done three times a week during two months. Afterward, specimens were submitted to different periods of artificial aging. Color evaluation was initially done, after 60 days (disinfection period) and after 252, 504, and 1008 h of artificial aging with aid of a reflection spectrophotometer. Data were analyzed by three-way ANOVA and Tukey test (alpha = 0.05). The isolated factor disinfection did not statistically influence the values of color stability among groups. The association between pigment and BaSO(4) opacifier (GIV) was more stable in relationship to color change (Delta E). All values of Delta E obtained, independent of the disinfectant and the period of artificial aging, were considered acceptable in agreement with the norms presented in literature. (C) 2011 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.3625401]

Exploring CBCT-Based DICOM Files. A Systematic Review on the Properties of Images Used to Evaluate Maxillofacial Bone Grafts

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Hyperbaric Oxygen: Therapy for Patients With Maxillofacial Implants?

Osseointegration was an innovative treatment in dentistry during the last 3 decades. The success of osseointegration is related to factors such as material biocompatibility, adequate quality of bone tissue that allows implantation, surgical technique, and macrostructure and microstructure of implant. The osseointegrated implants are successfully applied in dental clinic including oral and facial rehabilitations mainly for patients submitted to mutilating surgeries. However, patients submitted to radiation therapy present risks to treatment with implants owing to adverse effects on bone tissue. Nowadays, the literature suggests different therapies to improve the success of osseointegration such as hyperbaric oxygen therapy that aims to prepare bone and adjacent tissues to receive the implant. Therefore, the purpose of this study was to present a literature review concerning indications, contraindications, successes, and difficulties with hyperbaric oxygen therapy associated to maxillofacial implants.

Evaluation of hardness and surface roughness of two maxillofacial silicones following disinfection

The purpose of this study was to evaluate the Shore A hardness and surface roughness of two silicones for maxillofacial prosthetic treatment, under the influence of chemical disinfection and storage. Twenty-eight specimens were obtained, half of which were made of Silastic MDX 4-4210 silicone and, the other half were made of Silastic 732 RTV silicone. The specimens were divided into four groups: Silastic 732 RTV and MDX 4-4210 with disinfection 3 times a week with Efferdent tablets and the same materials without disinfection. The hardness of the materials was analyzed with a Shore A Durometer. The surface roughness was established by a digital portable roughness tester, initially and 2 months after the confection of the specimens. A variance test was applied (2-way ANOVA), followed by Tukey test (the level of significance was set at 1%). The storage time factor statistically influenced (p < 0.01) the materials' properties of hardness and roughness. MDX 4-4210 (28.59 Shore A, 0.789 Ra) presented higher values than Silastic 732 RTV (18.08 Shore A, 0.656 Ra) for both properties. Regarding the disinfection period, there was no significant difference in any of the materials tested. © 2009 Sociedade Brasileira de Pesquisa Odontológica.

Deep venous thrombosis prophylaxis in oral and maxillofacial surgery: a Brazilian survey

Background : Deep venous thrombosis (DVP) is a frequent disease. Prophylaxis is the best means to reduce its incidence, for lowering morbidity and mortality rates and treatment costs caused by its complications. Objective : To evaluate the knowledge and use of any kind of DVT prophylaxis by Brazilian Oral and Maxillofacial surgeons. Materials and Methods : A questionnaire was sent to all Oral and Maxillofacial surgeons associated to the Brazilian College of Oral and Maxillofacial Surgeons that have a valid e-mail address. The data retrieved was evaluated and tabulated. Results : Of the 1100 questionnaires sent, only 4% were retrieved. The 42 retrieved were included in the study. Twenty six of the surgeons do not use any kind of deep venous thrombosis (DVT) prophylaxis, 11 use mechanical means as elastic compressive stockings or pneumatic compressive devices for prophylaxis, and 5 uses low-molecular weight heparins (LMWH) as the choice for prophylaxis. Conclusion : The data collected, despite the low rate of participation (4%) by the surgeons, shows that this subject still does not receive proper attention. Whereas other medical specialties make routine use of prophylactic means maybe the maxillofacial surgeons lack concern on that matter.

Oral and maxillofacial trauma in brazilian children and adolescents

Crianças e adolescentes freqüentemente são vítimas de trauma nas regiões oral e maxilofacial. O objetivo deste estudo foi determinar as características do trauma na região oral e maxilofacial que resultaram em registros policiais, em crianças e adolescentes na faixa etária de 0 a 16 anos, por um período de 5 anos. Dos 28.200 laudos avaliados, 463 foram incluídos na pesquisa. A taxa homem:mulher observada foi de 1,6:1 e a faixa etária de maior ocorrência foi a de 15-16 anos (44,40%). A maioria dos casos de trauma foi decorrente de agressão física (64,50%) e resultou em lesão de tecido mole (80,36%). Entre os tipos mais freqüentes, destacam-se as escoriações (28,64%) e quanto à localização, a região maxilar (22,63%). O tipo de lesão dental mais comum foi trauma dental (54,76%), e as fraturas ósseas predominaram nas regiões nasal (36,7%). Os resultados encontrados podem auxiliar no planejamento e execução de medidas preventivas e direcionar medidas curativas dirigidas a este grupo populacional.

A six-year retrospective study of maxillofacial fractures from radiographic findings in Brazil

Objective: this study aimed to present the causes and prevalence of maxillofacial fractures that occurred in the region of Araraquara-SP – Brazil, during a 6-year period. Methods: information regarding age, gender, etiology, and maxillofacial fracture site, as well as type of radiographic examination were evaluated. Data were gathered from the radiographic examination and radiographic report of the Division of Dentomaxillofacial Radiology, and from charts of the Division of Oral and Maxillofacial Surgery of patients attending for maxillofacial fractures from 2004 to 2009. A descriptive statistical analysis was developed using Epi-Info 3.5.1. Results: from a total of 11,728 patients assisted, 407 patients presented maxillofacial fractures. The prevalent age ranged from 21 to 30 years old. From the total patients, 322 were men and 85 were women (ratio of men to women was 3.8:1). Panoramic radiography (n = 306) was most frequently used to observe maxillofacial fractures. Mandibular fractures were frequent in the body of the mandible (n = 127), followed by symphysis (n = 102), and the prevalent cause was traffic accidents (n = 161). Conclusion: more than half of affected individuals were younger than 40 years of age. The body of the mandible was the most common fracture location visualized by panoramic radiography for traffic accidents and fights.

Positioning magnets on a multiple/sectional maxillofacial prosthesis

Aim: The aim of this report is to describe a quick and simple method of positioning retention magnets when deformed patients are rehabilitated with an oculopalpebral prostheses attached to a maxillary denture/obturator. Background: In patients with deformities requiring complex rehabilitations, the use of magnets is the most efficient means of providing combined prostheses with retention quality and stability. Usually prostheses with magnets are in sections and have a magnet in each section. When the sections are put together properly, the magnets are attracted to each other and retain the sections. Report: An edentulous patient presented for a post-surgical evaluation of a maxillofacial prosthesis used to repair a partial maxillectomy and left orbital exoneration which removed all adjacent tissues leaving an open communication between the oral, nasal, and orbital cavities. The proposed treatment plan included construction of a maxillary complete denture with a palatal obturator and a mandibular complete denture. Magnets were used to attach the oculopalpebral prosthesis to the maxillary denture/obturator. Summary: Use of retention magnets simplify the clinical and laboratorial phase, retains the denture, and makes it stable and comfortable for the patient. This treatment is one successful approach to the restoration of oral function and increases the patient’s quality of life.

Rehabilitative treatment of cleft lip and palate: experience of the Hospital for Rehabilitation of Craniofacial Anomalies - USP (HRAC-USP) - Part 3: Oral and Maxillofacial Surgery

This paper presents the treatment protocol of maxillofacial surgery in the rehabilitation process of cleft lip and palate patients adopted at HRAC-USP. Maxillofacial surgeons are responsible for the accomplishment of two main procedures, alveolar bone graft surgery and orthognathic surgery. The primary objective of alveolar bone graft is to provide bone tissue for the cleft site and then allow orthodontic movements for the establishment of an an adequate occlusion. When performed before the eruption of the maxillary permanent canine, it presents high rates of success. Orthognathic surgery aims at correcting maxillomandibular discrepancies, especially anteroposterior maxillary deficiencies, commonly observed in cleft lip and palate patients, for the achievement of a functional occlusion combined with a balanced face.