Effect of glaze technology on adhesive and mechanical properties of Yttria-stabilized tetragonal zirconia polycrystal ceramic / 中国组织工程研究

BACKGROUND: Any surface treatments should Improve the bond strength of yttria-stabilized tetragonal zlrconia polycrystal ceramics without damaging the original strength. Currently, there is no Information about the influence of glaze technology on the bond strength of yttria-stabilized tetragonal zlrconia polycrystal ceramics, and its Influence on the material strength Is unclear. OBJECTIVE: To evaluate the effect of glaze technology on the mechanical behavior of yttria-stabilized tetragonal zlrconia polycrystal ceramics and on the bond strength with resin cements. METHODS: Yttria-stabilized tetragonal zlrconia polycrystal ceramics specimens were prepared and randomly divided into four groups: group A: the surface was not treated; group B: sandblasting with 110 urn Al203 particles; group C: glaze + hydrofluoric acid etching; group D: glaze + hydrofluoric acid etching + sllanlzation. The surface morphology, surface roughness, phase transformation, elemental composition, shear bond strength and flexural strength of zlrconia specimens after surface treatments were tested. RESULTS AND CONCLUSION: (1) The surface roughness of treatment groups increased obviously, whose descending order was group C (0.62±0.01) um > group D (0.55±0.02) um > group B (0.11±0.02) um > group A (0.05±0.01) urn (p 0.05). (6) The effect of glaze technology on improving the flexural strength of yttria-stabilized tetragonal zirconia polycrystal ceramics is not as obvious as that of sandblasting, but the bond strength between tetragonal zirconia polycrystal ceramics and resin cements can be significantly Improved with hydrofluoric acid etching and silanization after glaze.

Interações ambientais e resistência física de um depósito de resíduos finos da indústria de rochas ornamentais / Environmental interactions and physical resistance of a fine waste deposit from dimension stone industry

RESUMO Embora vários trabalhos proponham aplicações para os resíduos finos gerados no beneficiamento de rochas ornamentais, ainda não há evidências das vantagens financeiras para tal aproveitamento. Assim, a descrição dos depósitos existentes, muitos deles construídos sem triagem ou qualquer medida de proteção ambiental, torna-se imprescindível para seu melhor gerenciamento. Este trabalho estudou a caracterização física, química e mineralógica, além da resistência mecânica de um depósito de resíduos tradicionais e de seu substrato geológico. Cerca de 75% das partículas que compõem os resíduos são menores do que 0,0625 mm e o teor de umidade varia entre 26 e 60%. Os valores de pH variam entre 8,2 e 10,5. Os elementos químicos predominantes são Si, Al, Fe e, em menor proporção, Ca, Na e K. Esses elementos compõem quartzo, plagioclásio, microclina, calcita, muscovita, biotita e zircão. Ao comparar as características dos resíduos com as do substrato geológico, não foram encontrados indícios de migração das substâncias químicas analisadas. Os Stantard Penetration Tests mostram que as camadas não apresentam resistência suficiente para receber fundações rasas. É provável que as concentrações de Fe em alguns níveis contribuam com o aumento da resistência mecânica em áreas localizadas do depósito.

ABSTRACT Although several works propose applications for the fine wastes generated by the dimension stones processing, the financial advantages of recovering these materials are not yet evident. Then, the description of the deposits, much of them constructed without screening or any environmental protection measure, becomes indispensable for their best management. This work studies the physical, chemical and mineralogical characterization, as well as the mechanical resistance of a traditional waste deposit and its geological substrate. Around 76% of the particles that compound the wastes are smaller than 0,0625 mm and their humidity vary between 26 and 60%. The pH-values are between 8.2 and 10.5. The major chemical elements are Si, Al, Fe, and, at less proportions, Ca, Na, and K. These elements compound quartz, plagioclase, microcline, calcite, muscovite, biotite, and zircon. When comparing the characteristics of the wastes with the geological substrate, indicatives of the analyzed substances' migration was not found. The Standard Penetration Tests (SPT) show that the layer´s strength is not good enough to receive shallow foundations. It is probable that Fe concentrations at some levels contribute for incrementing the deposit´s mechanical resistance.

Ensaio em colunas de solo para estudo da influência dos resíduos finos de rochas ornamentais na qualidade da água / Soil column test to study the influence of dimension stone fine wastes on water quality

RESUMO A geração de resíduos finos provenientes do processo de beneficiamento de rochas ornamentais cresce na mesma proporção da produção de chapas para a construção civil. A adoção de medidas preventivas, remediadoras e punitivas está atrelada ao conhecimento do verdadeiro potencial que esses materiais têm para causar impactos negativos ao ambiente. O objetivo deste trabalho foi simular, em laboratório, possíveis alterações na qualidade da água de recarga de aquíferos provocadas pela disposição inadequada desses resíduos. Foram realizados testes de percolação de água em colunas de solo recoberto por resíduos com diferentes taxas de umidade: resíduos sem tratamento, saídos diretamente do tear (TE); resíduos que passaram por filtro prensa (FP) para redução de umidade e resíduos secos em leito de secagem (LS). A água de percolação foi analisada para avaliar alterações em comparação com um branco ou testemunha. Não foram detectadas alterações significativas no pH da água percolada em nenhum dos casos estudados. Porém, no tratamento TE houve alterações em vários parâmetros de qualidade. A água percolada através do resíduo FP se assemelhou àquela do TE em alguns parâmetros e à do LS em outros. ­Conclui-se que os resíduos saídos diretamente da boca do tear possuem alto potencial de degradação da qualidade da água, mas a redução de umidade é eficaz para reduzir os riscos ambientais. O uso de LS pode ser um método tão eficaz quanto o FP, se conduzido de forma adequada e respeitando as normas legais.

ABSTRACT The generation of fine wastes from cutting of ornamental stones grows at the same rate of plate production for civil construction. The adoption of safe, remediating and punitive measures are linked to the knowledge of the actual potentiality that these materials have for causing negative impacts to the environment. The aim of this work was to simulate, in laboratory, possible alterations in the recharging groundwater quality provoked by the improper disposal of these wastes. We conducted tests of percolating water through soil columns covered by wastes with different humidity rates: wastes without treatment, outgoing directly from the looms (TE); wastes that passed by filter press for humidity reducing (FP) and wastes dried in a drying pond (LS). Percolated water was analyzed to evaluate alterations of its quality in relation to a blank (B) or control. Significant changes did not occur in pH-values of percolated water in any of the cases studied. However, many water quality parameters were changed during TE treatment. The water percolated through FP residues was similar to that of the looms in relation to some parameters and with the LS wastes, in others. We concluded that the wastes that just left the loom have high potential for changing water quality, but the reduction of waste´s humidity is efficient for minimizing environmental risks. The use of drying bed could be as efficient as the filter press, if conducted in a proper form and according to legal regulations.

Emphysema following air-powder abrasive treatment for peri-implantitis / 대한악안면성형재건외과학회지

BACKGROUND: Subcutaneous emphysema refers to swelling caused by the presence of air or gas in the interstices of loose connective tissue. In the head and neck area, it may follow the fascial planes and is characterized by sudden swelling, crepitus on palpation, infrequent pain, and air emboli on radiography. It usually occurs as a complication in dental treatment. Some reports have described subcutaneous emphysema caused by dental procedures; however, severe emphysema related to peri-implantitis after treatment has not been documented. Accordingly, the current report describes a rare case of subcutaneous cervical emphysema resulting from the use of an air-powder abrasive device to treat peri-implantitis. CASE PRESENTATION: Based on a review of the existing literature and the present case, nine cases of subcutaneous emphysema due to air-powder abrasive device have been reported. In most cases, the emphysema resolved over time after treatment with prophylactic antibiotics; among these, two were related to peri-implantitis management. CONCLUSION: Considering the frequent use of air-powder abrasive devices to treat peri-implantitis, the potential risk of iatrogenic emphysema related to this procedure needs to be addressed more extensively.

Comparative analysis of different prophylactic methods for roughness of primary tooth enamel / Análise comparativa de diferentes métodos profiláticos sobre a rugosidade do esmalte em dentes decíduos

Objective: The purpose of this study was to comparatively evaluate quantitative effects of three different prophylactic methods of surface polishing treatments for primary teeth compared to a standardized control group. Material and Methods: 48 naturally exfoliated primary teeth were selected and randomly assigned into four groups: Control Group ­ teeth receiving only enamel standardization treatment with polishing disc to reduce natural enamel; Group I ­ teeth receiving superficial enamel standardization treatment followed by polishing with a mixture of water and pumice; Group II ­ teeth receiving enamel standardization treatment followed by prophylaxis with paste (Herjos-F, Vigodent S/A Indústria e Comércio, Rio de Janeiro, Brazil); and Group III ­ teeth receiving enamel standardization treatment followed by sodium bicarbonate spray (Profi II Ceramic, Dabi Atlante Indústrias Médico-Odontológicas Ltda, Ribeirão Preto, Brazil). All the procedures were performed by the same operator and the samples were rinsed and stored in distilled water. Comparative assessment of the enamel surface roughness between experimental groups and control group was performed by using a surface profilometer (Mitutoyo SJ400). Results: The results of this study were statistically analysed by using Minitab statistical software (version 17.1.0, 2013). The use of pumice and water led to significantly rougher surfaces than in other groups (i.e. Group I: 1.22 Ra; Group II 0.38 Ra; Group III: 1.01 Ra). Conclusion: Based on this study, one can conclude that use of pumice and water resulted in increased enamel surface roughness in comparison to the surface treatment with bicarbonate spray and prophylaxis paste. (AU)

Objetivos: O objetivo deste estudo foi quantificar e comparar a rugosidade do esmalte dentário após de três diferentes tratamentos profiláticos para polimento de superfície de esmalte em dentes decíduos, em relação a um grupo controle. Material e Métodos: 48 dentes decíduos naturalmente esfoliados foram selecionados e alocados aleatoriamente em quatro grupos. Grupo Controle: recebeu apenas padronização do esmalte através do disco de polimento para redução de dentes naturais. O grupo I recebeu padronização superficial do esmalte seguido de polimento por mistura de água e pedra-pomes; o grupo II recebeu padronização do esmalte seguido da pasta de profilaxia Herjos-F (Vigodent S / A Indústria e Comércio, Rio de Janeiro, Brasil); e o grupo III recebeu padronização da superfície do esmalte seguido de spray de bicarbonato de sódio Profi II Ceramic (Dabi Atlante Indústrias Médico Odontológicas Ltda., Ribeirão Preto, Brasil). Todos os tratamentos de superfície foram realizados pelo mesmo operador, por dez segundos e as amostras foram lavadas e armazenadas em água destilada. A avaliação comparativa da rugosidade superficial do esmalte entre os grupos experimentais e controle foi realizada utilizando-se um perfilômetro de superfície Mitutoyo SJ400. Resultados: Os resultados deste estudo foram analisados estatisticamente com o software estatístico Minitab (versão 17.1.0, 2013). A pedra-pomes e a água geraram significativamente maior aspereza na superfície de esmalte, em comparação aos outros grupos, quando empregado o teste estatístico de Tukey (Grupo I: 1,22 Ra; Grupo II: 0,38 Ra; Grupo III: 1,01 Ra). Conclusão: Com base neste estudo, pode-se concluir que a pedra-pomes e a água resultaram em aumento da rugosidade superficial do esmalte em comparação ao tratamento superficial com spray de bicarbonato e pasta profilática.(AU)

Subcutaneous emphysema after treatment through airabrasivedevice: case report / Enfisema subcutâneo gerado após tratamento com equipamento de ar comprimido: relato de caso

Subcutaneous emphysema is an event often generated by iatrogenic reason, caused by improper dissection of air into soft tissues and/ or anatomical structures, causing edema and visually noticeable volumetric change in the area of the incident. The main etiological factor for this is the use of equipment such as air syringe or high-speed handpieces in surgical procedures of greater magnitude; however, subcutaneous emphysema may also occur in simple procedures, such that presented in this case report, through using air-abrasive device usually proper for dental prophylaxis. This case report aimed to describe the care measurements to avoid such event, describing proper procedures for the correct solution of the case, as well as to alert the professionals about the risks and necessary precautions.

O enfisema subcutâneo é um evento muitas vezes de origem iatrogênica, causado pela infusão indevida de ar nos tecidos e/ou estruturas anatômicas, causando edemaciamento e alteração volumétrica visualmente perceptível na área do ocorrido. O principal fator etiológico para tal é o uso de equipamentos como seringa tríplice ou caneta de alta rotação durante procedimentos cirúrgicos de maior magnitude; no entanto, o enfisema subcutâneo também pode ocorrer diante de procedimentos mais simples, tal como o ocorrido no presente relato de caso, em que houve sua ocorrência pelo uso de equipamento de ar comprimido usualmente utilizado para execução de profilaxia. O objetivo do presente artigo foi relatar o caso, assim como descrever os cuidados para se evitar tal evento, e descrever procedimentos adequados para o correto prosseguimento e resolução adequada do caso.

Effect of whitening dentifrices on surface roughness of dental nanofiller-based composites. Stereomycroscopyand AFM analysis / Efeito de dentifrícios clareadores na rugosidade superficial de compósitos de nanoparticulados. Estereomicroscopia e AFM

Objective: the aim of this study was to assess the effects of whitening dentifrices on the surface roughness of three commercial nanofiller-based composite. Material and Methods: two optical analyses were performed: stereomicroscopy and atomic force microscopy (AFM). Disks (8.0 diam. x 2.0 mm thick.) of the nanocomposite Z350 (3M ESPE) and two nano-hybrid composites (EsthetXHD, Dentsply and Premisa, Kerr) were submitted to in vitro brushing (1000 cycles) with three whitening dentifrices (Colgate Luminous White, Oral-B 3D White e Close-Up Diamond Attraction) and a control (Colgate Total12). The results were analyzed by stereomicroscopy and rated according to the following criteria: 0 – no observed roughness, 1 – average roughness, 2 – great roughness. Data was submitted to Kruskall-Wallis non-parametric test followed by Tukey test (p = 0.05). Z350 specimens were assessed by AFM. Results: the surface roughness of composites brushed with whitening dentifrices was statistically higher than the roughness found in specimens brushed with conventional dentifrice. AFM analyses showed that, at a submicrometric scale, there was an increase in the number of peaks and irregularities in specimens brushed with whitening dentifrices. Conclusion: Whitening dentifrices may have an impact on the longevity of dental composites by an increase in its roughness. It is strongly recommended that clinicians guide their patients, warning them about the risks and consequences of their use.

Objetivo: o objetivo deste estudo foi avaliar os efeitos da abrasão produzida por dentifrícios clareadores sobre as superfícies de três marcas comerciais de resinas compostas contendo partículas nanométricas. Materiais e Métodos: A resina nanoparticulada Z350 (3M ESPE) e as resinas nano-híbridas EsthetXHD (Dentsply) e Premisa (Kerr) foram submetidas à escovação in vitro com três diferentes dentifrícios clareadores (Colgate Luminous White, Oral-B 3D White e Close-Up Diamond Attraction). Os espécimes de resina foram confeccionados com 8mm de diâmetro e 2mm de espessura. Foram produzidos 45 corpos de prova para os grupos experimentais e mais 15 espécimes para o grupo controle (dentifrício Colgate Total12). Após a realização de 1.000 ciclos de escovação, os espécimes foram armazenados em saliva artificial. A análise das superfícies escovadas foi obtida por estereomicroscópio. As rugosidades foram mensuradas segundo os critérios: 0 – sem rugosidade, 1 – média rugosidade e 2 – com muita rugosidade. Os dados obtidos foram analisados estatisticamente por teste não-paramétrico de Kruskall-Wallis seguido pelo teste de Tukey (p < 0,05). Os espécimes confeccionados com Z350 foram avaliados por microscopia de força atômica (AFM). Resultados: A rugosidade superficial dos espécimes de resina composta foi estatisticamente maior quando escovados com os dentifrícios clareadores em relação ao dentifrício controle convencional. Análise por AFM demonstrou, em uma escala submicrométrica, um aumento no número de picos na superfície dos espécimes da resina em que foi realizada a escovação com dentifrícios clareadores em comparação com o grupo controle. Conclusão: Os dentifrícios clareadores aumentaram a rugosidade superficial das resinas compostas podendo, assim, diminuir a sua longevidade.

Abrasive wear of two glass ionomer cements after simulated toothbrushing

Introduction and objective: Glass ionomer cement, which was first introduced in Dentistry in 1972, presents good qualities such as aesthetics, fluoride release and adhesion to dental tissues. Because of its preventive characteristics regarding to dental caries, glass ionomer cement has been used for Atraumatic Restorative Treatment (ART), as reported by Frencken and Holmgren 6, meeting the principles announced by the World Health Organization (WHO) for application to large population groups without regular access to dental care. Material and methods: In this present study, the abrasive wear strength of two glass-ionomer cements (Vidrion R® and ChemFlex®) was evaluated through toothbrushing machine. Classic® toothbrushes with soft bristles and Sorriso® dentifrice were also used for the study. Results: Student-t test showed significant difference between both groups, with tobs value = 9.4411 at p < 0.05. Conclusion: It can be concluded that the wear rate caused by toothbrush/dentifrice was higher for Vidrion R® (52.00 mg) than ChemFlex® (5.57 mg).

Desgaste abrasivo de uma resina composta, através de três diferentes métodos (disco retificado, escovação e nanodurômetro) / Abrasive wear of a composite resin, using three different methods (ground disc, toothbrushing and nanodurometer)

Neste estudo, foi avaliada a resistência ao desgaste abrasivo de uma resina composta, através de três diferentes métodos: do disco retificado, por escovação e do nanodurômetro. Nos dois primeiros métodos, foram utilizados 20 espécimes da resina Filtek Z250 (10 da cor Incisal e 10 da cor C4, ambos fotopolimerizados por 30 segundos cada) e 10 de polimetilmetacrilato (PMMA), atuando estes últimos como padrão de referência. Para os ensaios com o nanodurômetro, foi utilizado apenas um espécime de cada cor, assim como um único de PMMA, em cujas superfícies planas foram efetuadas sete medições, o que foi considerado equivalente a sete espécimes. No método do disco retificado, cada espécime de resina composta era confeccionado diretamente numa cavidade semicircular, localizada na periferia de um disco-suporte; os espécimes de PMMA consistiam em discos constituídos exclusivamente por este material; o desgaste de cada espécime era promovido por um disco de porcelana e seu conseqüente deslocamento era detectado por um palpador; assim, a taxa de desgaste era estabelecida, expressa em milímetros cúbicos por newton por segundo (mm3/N.s). No método de escovação, cada espécime cilíndrico ficava preso numa placa metálica, a qual era fixada no interior da máquina de escovação; sua perda de massa (em miligramas) era verificada através de uma balança analítica. No método do nanodurômetro, existiu apenas um espécime ci líndrico para cada condição, em cuja face plana superior eram feitos sete sulcos (equivalentes a sete espécimes); o coeficiente de atrito permitia estabelecer a respectiva resistência ao desgaste. Para cada método utilizado, os dados foram tratados estatisticamente, através de análise de variância (ANOVA) e de teste de Tukey. Pôde-se concluir que, através do disco retificado, a taxa de desgaste (em mm3/N.s) dos materiais foi: Incisal (0,6807) > C4 (0,5012) > PMMA (0,1439); que, através da escovação, a taxa de desgaste (em mg) foi de 5,40 para...

Abrasive wear of a composite resin, using three different methods (ground disc, toothbrushing and nanodurometer). The aim at this study was to evaluate the resistance to abrasive wear of a composite resin, using three different methods: ground disc, toothbrushing and nanodurometer. At the first two methods were employed 20 specimens of Filtek Z250 composite resin (10 of Incisal and 10 of C4, both the colors cured for 30 seconds each one) and 10 of polymethylmethacrylate (PMMA), the latter acting as a reference standard. For the tests with the nanodurometer it was used only one specimen of each color, as well as just one of PMMA, in whose flat surfaces seven measurements were made, what was considered equivalent to seven specimens. At the ground disc method, each composite resin specimen was directly made on a semicircular cavity located on the periphery of a supporting disc; PMMA specimens consisted of discs made up exclusively with this material; the wear of each specimen was promoted by a ceramic disc and its consequent displacement was detected by a sensor; thus, the wear rate was established, expressed in cubic millimeters per newton per second (mm3/N.s). At the toothbrushing method, each cylindrical specimen was trapped in a metal plate, which was fixed inside the machine brushing; its weight loss (in milligrams) was verified by an analytical balance. At the nanodurometer method, there was only one cylindrical specimen for each condition, in whose flat upper face seven grooves were made (what was equivalent to seven specimens); the coefficient of friction was used to establish its wear resistance. For each method, data were statistically analyzed by ANOVA and Tukey's test. It could be concluded that, by ground disc method, materials wear rate (in mm3/N.s) was Incisal (0.6807) > C4 (0.5012) > PMMA (0.1439); by brushing method, materials wear rate (in mg) was 5.40 for Incisal, 9.35 for C4 and 5.88 for PMMA, without significant difference...

The influence of the die hardener on gypsum die / 대한치과보철학회지

STATEMENT OF PROBLEM: Die materials require abrasion resistance, dimensional stability with time, and high surface wettability for adequate material properties. Wear of gypsum materials is a significant problem in the fabrication of accurately fitting cast prosthetic devices. So It has been recommended that the use of die hardener before carving or burnishing ofthe wax pattern. PURPOSE: The purpose of this study was to compare the abrasion resistance and surface microhardness(Knoop) with 3 commonly used gypsum die materials(MG Crystal Rock, Super plumstone, GC FUJIROCK(R) EP) with and without the application of 2 die hardeners. MATERIAL AND METHODS: Three die materials were evaluated for abrasion resistance and surface microhardness after application of 2 die hardeners(Die hardener and Stone die & plaster hardener). Thirty specimens of each gypsum material were fabricated using an impression of resin die(Pattern resin; GC Corporation, Japan) with 1-mm high ridges, sloped 90 degrees. Gypsum materials were mixed according to manufacturer's recommendations and allowed to set 24 hours before coating. Specimens were arbitrary assigned to 1 of 3 treatment subgroups (n=10/subgroup): no treatment(control), coated with Die hardener, and coated with Stone die & plaster hardener. Abrasion resistance(measured by weight loss) was evaluated using device in 50g mass perpendicular to the ridges. Knoop hardness was determined by loading each specimen face 5 times for 15 seconds with a force of 50g. A scanning electron microscope was used to evaluate the surface of specimens in each treatment subgroup. Conclusions: The obtained results were as follows: 1. 3 types of die stone evaluated in this study did not show significant differences in surface hardness and abrasive resistance(P<.05). 2. In the abrasive resistance test, there were no significant differences between GC FUJIROCK(R) EP and MG Crystal Rock with or without 2 die hardener(P<.05). 3. Super plumstone treated with Stone die & plaster hardener showed increased wear loss(P<.05). 4. Die hardener coatings used in this study decreased the surface hardness of the gypsum material(P<.05).

microabración del esmalte técnica para la remoción de manchas dentales

Los cambios en los conceptos acerca del cuidado dental, la mejora de los materiales y técnicas y la preocupación de los pacientes por su aspecto, han sido responsables del aumento de la importancia de la Odontología Estética en los últimos años. La técnica de Microabrasión del Esmalte es aplicada como una alternativa estética en aquellos casos donde se deseen eliminar manchas blancas, vetas, coloraciones parduscas o pigmentaciones por desmineralización, de una manera rápida, efectiva y conservadora. La técnica se basa en la microreducción química y mecánica del esmalte superficial.

Resumo As mudanças nos conceitos sobre o cuidado dental, a melhoria dos materiais e as técnicas e o preocupação dos pacientes por seu aspecto, os anos foram responsáveis para o aumento da importância da Odontologia estética nos últimos anos. A técnica de MicroabraÇao de Esmalte é aplicada como alternativa estética naqueles casos a onde são desejados elimine os pontos brancos, veias, coloração ou pigmentação cinzentos pelo dêsmineralizaÇao, de uma maneira rápida, eficaz e preservativo. A técnica é baseada no produto químico e no micro redução mecânico do esmalte superficial.

Abstract Changes in concepts on dental care, improving of materials and techniques and worrying of the patients about their looks, have been responsible for the increment of Esthetic Dentistry's importance in recent years. The technique of Enamel Microabration is applied as an esthetic alternative in those cases where the elimination of white spots, veins, grayish and brown stains or pigmentations by demineralization, is desired in a rapid, effective and conservative way. The technique is based on chemical and mechanical microreduction of the superficial enamel.

Evaluation of the mass-screening of the uterine cervical cancer using Kato's Self-abrasive Device in China / 日本農村医学会雑誌

Using Kato's Self-abrasive Device, mass-screening for uterine cervical cancer has been carried out for 5, 983 married women at Chicheng country of a mountainous farm village and Shijiazhuang city in Hebei province, China, and the following result has obtained:<BR>The women who diagnosed as class III and over were 42 persons (0.70%). Cancer cases which were confirmed by the biopsy were 10 (3 at Shijiazhuang city and 7 at Chicheng country); the occurrence rate of the cervical cancer was 0.17% and no false positive was observed. The mass -screening of the uterine cervical cancer has been carried out simultaneously by both way of the self-abrasive method and the scraper method for one third of persons who will take medical advice atboth districts. The result of comparative analysis for the quality of smear and the Papanicolaouclassification by the two method was;<BR>1. As for the self-abrasive method, mixing with erythrocytes and overlapping of cells were few compared with the scraper method, and the diagnosis was more easily made in cytological examination.<BR>2. The rate of coincidence by both methods were 78.85% in class I, 94.14% in class II, and 100.00% in class III-V.