Marcelo Fava

DENTAL APPROACH IN THE PEDIATRIC ONCOLOGY PATIENT: CHARACTERISTICS OF THE POPULATION TREATED AT THE DENTISTRY UNIT IN A PEDIATRIC ONCOLOGY BRAZILIAN TEACHING HOSPITAL

OBJECTIVES: The objective of this paper was to characterize the population seen at the dentistry unit of the hematology-oncology service of the Oncology-Hematology Service, Instituto da Criança at the Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo. Oral problems resulting from cancer therapy increase the risk of infection, length of hospital stay, treatment cost and negative impact on the course and prognosis of the disease. METHOD: Of the 367 medical records of cancer patients seen from November 2007 until December 2008: 186 with a cancer diagnosis and complete clinical data were selected, while 20 with a cancer diagnosis and incomplete records were excluded; 161 medical records with only hematological diagnosis were also excluded. The following characteristics were assessed: ethnicity, gender, age, diagnosis and characteristics of the neoplasm, cancer therapy status and performed dental procedures. RESULTS: Review of 1,236 visits indicated that 54% (n=100) of the patients had blood cancers, 46% (n=86) had solid tumors and 63% were undergoing anticancer therapy. The proportion of males (52.7%) in the study population was slightly greater. The most common cancer was acute lymphocytic leukemia (32.2%). Cancer occurred more often among those patients aged 5 to 9 years. The most common dental procedures were restorative treatment, preventive treatment and removal of infectious foci. CONCLUSION: The characteristics of the studied population were similar to those of the general Brazilian and global populations, especially regarding gender and diagnosis distributions. The aim of implementation of the dentistry unit was to maintain good oral health and patients’ quality of life, which is critical to provide oral care and prevent future oral problems.

In vitro evaluation of the microhardness of bovine enamel exposed to acid solutions after bleaching

Acid erosion is a superficial loss of enamel caused by chemical processes that do not involve bacteria. Intrinsic and extrinsic factors, such as the presence of acid substances in the oral cavity, may cause a pH reduction, thus potentially increasing acid erosion. The aim of this study was to evaluate the microhardness of bleached and unbleached bovine enamel after immersion in a soda beverage, artificial powder juice and hydrochloric acid. The results obtained for the variables of exposure time, acid solution and substrate condition (bleached or unbleached enamel) were statistically analyzed by the ANOVA and Tukey tests. It was concluded that a decrease in microhardness renders dental structures more susceptible to erosion and mineral loss, and that teeth left unbleached show higher values of microhardness compared to bleached teeth.

Estudo morfologico do esmalte dentário humano sob a ação de diferentes métodos profiláticos: análise ao microscópio eletrônico de varredura

The purpose of this in vitro stu- dy was to evaluate, by scanning elec- tron microscopy, alterations in the micromorphology of human enamel submitted to three prophylaxis me- thods. Forty caries-free premolars were divided into four groups of 10 samples each. The first group was treated with sodium bicarbonate spray Profident (Dabiatlante); the second group with a mix of water and pumice slurry (S.S. White); the third group with a prophylaxis pas- te Herjos-F (Vigodent S.A.) and the fourth group received no prophyla- xis treatment, being considered the control. After the treatment the sample were rinsed with air/water spray, dehydrated, coated with gold and examined in a scanning elec- tron microscope JEOL, JSM-6.100. The following observations were ob- tained using the SEM: (1) samples in group I presented an irregular surface with no scratch marks and granular material were observed on its surface, (2) group II presented many enhanced scratch marks on its surface, (3) granular materials were also observed on the surface of group III, which presented few scra- tch marks. Key words: dental enamel, dental prophylaxis, microscopy, electron, scanning.

Efeitos do ácido fosfórico nas concentrações de 10% ou 32% sobre a superfície do esmalte dental: estudo ao microscópio eletrônico de varredura

O objetivo deste estudo in vitro foi de avaliar os efeitos de duas diferentes concentracoes de acido fosforico e tempos de condicionamento, na morfologia do esmalte dentario de premolares humanos higidos. A superficie vestibular de 18 premolares extraidos de pacientes jovens, foi submetida a acao do acido fosforico nas concentracoes de 10% ou 32% por 15, 30 ou 60 segundos. Os resultados obtidos ao microscopio eletronico de varredura demonstraram a formacao de uma superficie de esmalte rugosa, com padroes variaveis de condicionamento, independentemente do tempo de aplicacao e das concentracoes utilizadas.