Evaluation of iris color stability in ocular prosthesis

Accurate iris reproduction in the fabrication of ocular prosthesis in order to match the remaining eye is a key factor to mask the loss and achieve an esthetic outcome for anophthalmic patients. This study evaluated the stability of acrylic paints used for replicating iris color in ocular prostheses by the analysis of two factors: the temperature of the acrylic resin polymerization cycle during prosthesis fabrication and the incidence of sun light, which is the main photodegrading agent undermining the longevity of ocular prostheses. An accelerated aging assay was used for both analyses. Specimens simulating the prosthetic iris in the colors blue, yellow, black, brown and green were fabricated, and were submitted to a colorimetric reading before and after undergoing the thermal conditions of acrylic resin polymerization. Next, the specimens were submitted to an artificial accelerated aging assay with ultraviolet radiation A and weekly colorimetric readings during a 3-week period. The color change (??*) values for the four specimens painted with the same color paint were averaged and the resulting values were considered for statistical analysis. Levine's test and Student's t-test were used to analyze the influence of the temperature of the polymerization cycle during prosthesis fabrication on the color stability of each acrylic resin paint. Friedman's test for three dependent samples was used for analysis of color photodegradation as function of time. Significance level was set at 0.05 for all analyses. It was observed that, after the action of the temperature of the polymerization cycle, alteration above clinically acceptable level of ??*> 3.3 was observed only for the yellow color. After the accelerated aging assay, there were statistically significant differences (p<0.05) as a function of time in the green, brown, black and blue colors. Changes were clinically acceptable for the brown and black colors; slightly above the clinically acceptable limit for the green color; and significantly high and impracticable from a clinical standpoint for the blue color. There was no statistically significant differences (p>0.05) for the yellow color, which presented color change only a little above the clinically acceptable limit. In conclusion: 1. Only the yellow color presented alterations above the clinically acceptable levels after the polymerization cycle; 2. After accelerated aging, there was no changes in the yellow color above the clinically acceptable levels; 3. For the green color, degradation was significant and slightly above the clinically acceptable levels; 4. The black, brown and blue colors presented significant alterations as function of time; the alterations of the brown and black colors were within acceptable clinical levels, while the blue color presented a more accentuated degradation over time.A fiel reprodução da íris do olho remanescente através da pintura na confecção da prótese ocular é fator fundamental no resultado estético e na dissimulação da perda para os pacientes afetados. Decidiu-se, então, avaliar a estabilidade das cores da tinta acrílica utilizada na pintura da mesma, sob a ação de dois fatores: a temperatura do ciclo de polimerização da resina acrílica e a incidência da luz solar, principal agente de fotodegradação que compromete a longevidade das próteses oculares, através de teste de envelhecimento acelerado. Foram assim, confeccionados corpos de prova simulando a íris protética, nas cores azul, amarelo, preto, marrom e verde, submetidos a uma leitura colorimétrica inicial e outra após as condições térmicas do ciclo de polimerização. Posteriormente os mesmos foram testados durante três semanas através de ensaio de envelhecimento acelerado artificialmente com radiação ultravioleta A e leituras colorimétricas semanais. Através dos valores da alteração de cor (DE*) foi obtida uma média para as quatro amostras pintadas com a mesma cor e os valores resultantes foram submetidos à análise estatística. Os testes de Levine e t de Student foram utilizados para analisar a influência da temperatura do processo de polimerização na estabilidade de cada cor utilizada na fabricação das próteses. O teste de Friedman para três amostras dependentes foi usado para analisar a degradação de cor em função do tempo. O nível de significância foi de 0,05 para todas as análises. Após a ação da temperatura do ciclo de polimerização, observou-se que somente na cor amarelo ocorreu alteração acima do nível clinicamente aceitável (p<0,05). Após o ensaio de envelhecimento, ocorreram diferenças estatisticamente significantes em função do tempo nas cores verde, marrom, preto e azul. A variação de cor ocorreu em níveis considerados clinicamente aceitáveis para as cores marrom e preto; levemente acima dos níveis clinicamente aceitáveis para a cor verde; e em níveis elevados, inviáveis clinicamente para a cor azul. Na cor amarelo não houve diferenças estatisticamente significantes (p>0,05), com alteração apenas um pouco acima do limite considerado clinicamente aceitável. Em conslusão: 1. Somente a cor amarelo apresentou alteração acima dos níveis clinicamente aceitáveis após o ciclo de polimerização; 2. Após o envelhecimento artificial, não houve alterações na cor amarelo acima dos níveis clinicamente aceitáveis; 3. Para a cor verde, a degradação foi significante e um pouco acima dos níveis clinicamente aceitáveis; 4. As cores preto, marrom e azul apresentaram diferenças significantes em função do tempo; as alterações das cores marrom e preto foram em níveis clinicamente aceitáveis, enquanto a cor azul apresentou um elevado índice de degradação de cor em todo tempo

Prevalence of malocclusions in the 13-20-year-old categories of football athletes

The dentist can offer athletes improvement in their physical performance through the maintenance of oral health, preventing and treating any and all changes in the stomatognathic system, such as dental malocclusions, that compromise the athletes' performance. The objective of this study is to research the presence of dental malocclusions in athletes of the category between 13 and 20 years of age, from the São Paulo Football Club. 84 athletes participated in this study, dealing with the following topics: molar relation (Angle's classification); presence of overbite; underbite; overcrowding; abnormal spacing; open bite; and anterior, posterior, bilateral and unilateral crossbite; midline deviation and facial type (mesofacial, brachyfacial and dolichofacial). Only one table was made, showing percentages. In regard to Angle's molar relation, 89% are in Class I, 8% in Class II, 3% Class III, 9% of the athletes had overbite, 4% had underbite, 13% had overcrowding and 21% had abnormal spacing. In regard to the bite, 11% presented anterior open bite. In regard to crossbite, 7% presented unilateral crossbite on the right side and 2% on the left side; 5% presented posterior crossbite and 4% anterior crossbite. In regard to midline deviations, 4% presented deviation in the maxilla and 33% in the mandible. In regard to facial type: 39% are dolichofacial, 4% brachyfacial and 57% mesofacial. Based on the results shown, proposals for the implementation of dental, phoniatric, and Ear, Nose and Throat (ENT) practices are already being discussed with the multidisciplinary team of the club involved

Systematic Study of Ethylene-Vinyl Acetate (EVA) in the Manufacturing of Protector Devices for the Orofacial System

Fracture of facial bones and dental elements, and laceration of soft tissue, have increased in sports over recent years. Dentist is the only professional responsible for the mouth protection design, the knowledge about suitable materials is essential. EVA is a thermoplastic material, available in the market, easy of handling and processing, and low-cost. However, it is important to understand the mechanical properties and ability to absorb and to dissipate the impact energy, when this material is submitted to different environments, such as oral cavity with saliva and different temperatures. This chapter show provides a systematic evaluation of the EVA application in orofacial protectors while focusing on sports. The research comprises two aspects: experimental tests and numerical analyses. During experimental tests, EVA was analyzed in special buccal conditions, concerning temperature and presence of saliva. Regarding the presence of saliva, more specific studies about its influence on the mechanical behavior of EVA were performed. In the numerical analyses of the EVA orofacial protector, the studies focused on its effect on the nasal bone integrity, and in the zygomatic bone protection. However, life cycle should be analyzed, since its performance deteriorates over time. Mainly due to the saliva-originated changes to the EVA mechanical characteristics, it can behave as a rigid material. For facial protection, a better performance is obtained with a combination of rigid and soft EVA material. According to the experimental and numerical results from a systematic study of EVA, its application to orofacial protection can be considered satisfactory

Photoelastic Stress Analysis Surrounding Implant-Supported Prosthesis and Alveolar Ridge on Mandibular Overdentures

The purpose of this research was to evaluate the maximum stress around osseointegrated implants and alveolar ridge, in a mandible with left partial resection through a photoelastic mandibular model. The first group consisted of two implants: traditional model (T), implants placed in the position of both canines; fulcrum model (F), implants placed in the position of left canine CL and right lateral incisor LiR. Both models linked through a bar and clips. The second group was consisted of three implants, with implants placed in the position of both canines (CR and CL) and the right lateral incisor (LiR), which composed four groups: (1) model with 3 “O” rings, (2) model 2 ERAs, bar with clips, (3) model 2 ERAs bar without clips; (4) model “O” ring bar and ERA. An axial and an oblique load of 6.8 kgf was applied on a overdenture at the 1st Pm, 2nd Pm, and 1st M. Results showed that the area around the left canine (CL) was practically free of stress; the left lateral incisor (LiL) developed only small tensions, and low stress in all the other cases; the right canine tooth suffered the largest concentrations of stress, mainly with the ERA retention mechanism

Candida albicans in patients with oronasal communication and obturator prostheses

Patients using obturator prostheses often present denture-induced stomatitis. In order to detect the presence of oral Candida albicans in patients with oronasal communications and to evaluate the effectiveness of a topical antifungal treatment, cytological smears obtained from the buccal and palatal mucosa of 10 adult patients, and from the nasal acrylic surface of their obturator prostheses were examined. A therapeutic protocol comprising the use of oral nystatin (Mycostatin®) and prosthesis disinfection with sodium hypochlorite was prescribed for all patients. Seven patients were positive for C. albicans in the mucosa, with 1 negative result for the prosthetic surface in this group of patients. Post-treatment evaluation revealed the absence of C. albicans on prosthesis surface and on the oral mucosa of all patients. The severity of the candidal infection was significantly higher in the palatal mucosa than in the buccal mucosa, but similar in the palatal mucosa and prosthesis surface, indicating that the mucosa underlying the prosthesis is more susceptible to infection. The therapeutic protocol was effective in all cases, which emphasizes the need for denture disinfection in order to avoid reinfection of the mucosa.Os pacientes portadores de prótese obturadora freqüentemente apresentam estomatite protética. Com o objetivo de detectar a presença de Candida albicans oral em pacientes com comunicação oronasal e avaliar a eficácia de um tratamento tópico antifúngico foi realizada citologia esfoliativa da mucosa palatina e jugal e da superfície acrílica nasal da prótese obturadora. O protocolo terapêutico consistiu de nistatina (Mycostatin®) para tratamento da mucosa oral e uma solução de hipoclorito de sódio para desinfecção da prótese. Sete pacientes (70%) apresentaram resultado positivo para C. albicans na mucosa, com um resultado negativo para a superfície protética neste grupo. A avaliação após o tratamento revelou ausência de C. albicans na mucosa oral de todos os pacientes, bem como na superfície protética. A infecção por C. albicans das mucosas jugal e palatina diferiram significantemente, enquanto que a mucosa palatina e a superfície protética apresentaram valores semelhantes. O grau de infecção da mucosa palatina foi significantemente maior quando comparado àquele da mucosa jugal e semelhante ao apresentado pela prótese, sugerindo que a mucosa subjacente à prótese é mais susceptível à infecção. O protocolo terapêutico foi efetivo em todos os casos, o que enfatiza a necessidade da desinfecção protética para se evitar a reinfecção da mucosa oral

Evaluation babies with cleft lip and/or palate related to the oral hygiene

Avaliou-se a prevalência de cárie relacionada à ausência de higiene oral, em bebês portadores de fissura labiopalatina, na faixa etária entre 6 e 36 meses. As crianças eram atendidas no Ambulatório da Disciplina de Prótese Buco Maxilo Facial, do Depto. de Cirurgia, Prótese e Traumatologia Maxilo Faciais da FOUSP. Profilaxia prévia ao exame clínico foi realizada para aumentar a confiabilidade do diagnóstico de cárie, o qual foi obtido por meio da inspeção visual e tátil, sob iluminação artificial. Selecionou-se 143 crianças sem distinção de gênero, distribuídos em 5 faixas etárias: 06-12; 13-18; 19-24; 25-30 e 31-36 meses. A análise estatística utilizou o Teste Qui-quadrado, ajustado pela Estatística de Fisher. Ao ser analisada a ausência de higiene oral em relação à experiência de cárie, não se observou significância estatística (p=0,626). Quando se avaliou a prevalência cárie frente ao aumento da idade e a ausência de higienização houve associação estatísticamente siginificante (p 0,001). Concluiu-se que, para esta amostra, a ausência de higiene oral não foi fator de incremento na manifestação da cárie.The study evaluated the caries prevalence related to the lack of oral hygiene in babies aged 6 to 36 months, with cleft lip and/or palate. Those children were treated in the Ambulatory of the Discipline of Bucco-Maxillo-Facial Prostheses, from the Department of Surgery, Prostheses and Maxillo-Facials Traumatology of the FOUSP. Before the clinical exam, prophylaxis was done to increase reliability of the visual and tactile inspection under artificial light. Were selected 143 children regardless of gender, distributed into 5 age groups: 06-12; 13-18; 19-24; 25-30 e 31-36 months old. The statistical analysis used the Q-Square-Test, adjusted by the Fischer’s Statistic. The analysis of the lack of oral hygiene correlated with the caries experience was not statistically significant (p=0,626). When the prevalence of caries was evaluated front to the increase of the age and the lack of oral hygiene, a statistical significant association was found (p< 0,001). The findings of the research didn’t show, in the sample, the lack of oral hygiene as a factor to increase the caries presence

Popularization of oral self-examination: an example of non formal education - Part II

Um dos maiores desafios das universidades, em especial das públicas, é transpor o conhecimento científico produzido entre seus muros para a população em geral. A educação não formal é uma ferramenta importante e ainda pouco utilizada pelos pesquisadores e docentes para aproximar o cotidiano do conhecimento científico. O câncer de boca atinge mais 11.000 brasileiros por ano. A despeito da alta incidência, esta patologia é ainda pouco conhecida da população em geral e de parte da classe médica e odontológica. Baseando-se nos dados epidemiológicos, em pesquisas e artigos científicos, o câncer de boca foi o tema eleito para a ação em educação e comunicação da primeira campanha nacional, de caráter não governamental, de prevenção de câncer de boca, um ótimo exemplo de como isso pode ser feito. Este trabalho se propõe a descrever a metodologia de comunicação utilizada e os resultados obtidos nesta experiência.One of the largest challenges of the universities, especially the public ones, is to transpose the scientific knowledge produced into their walls for the general population. The non-formal education is an important tool, and yet very little used by researchers and professors to approximate the scientific knowledge. The oral cancer reaches more than 11.000 Brazilians a year. In spite of the high incidence, this pathology is still little known by the general population and part of the medical and dental class. Basing on the epidemic data in researches and scientific papers, the oral cancer was the elect theme for the action in education and communication of the first national campaign with no government character of prevention in oral cancer, being a great example of as that can be made. This paper intends to describe the methodology used in communication and the results obtained in this successful experience.Universidade de São Paulo - FOUSPUniversidade de São Paulo - FMUSPHCFMUSP - Universidade de São Paulo (USP