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1.
Journal of Pharmaceutical Practice ; (6): 403-407, 2023.
Article in Chinese | WPRIM | ID: wpr-978477

ABSTRACT

Functional peptides refer to peptides that are beneficial to life activities or have special physiological activities, also known as bioactive peptides. Oyster is rich in protein and is a good material for developing bioactive peptides, which has great potential as a functional food and great application value in pharmaceutical and medical industry. With the development of modern biotechnology and medical technology, the method innovation of oyster peptide preparation,the absorptivity and biological activity of oyster peptide have been enhanced significantly, which lead to deep recognition of the biological function of oyster peptide and offer the boarder application prospect. The researches on the diversification activities of oyster peptides were summarized in this review, which provided clues and ideas for the development of the oyster peptide applications.

2.
Odovtos (En línea) ; 23(3)dic. 2021.
Article in English | LILACS, SaludCR | ID: biblio-1386564

ABSTRACT

ABSTRACT: The aim of this study was to compare the cyclic fatigue resistance (CFR) of PathFile (Dentsply Sirona, Ballaigues, Switzerland) and ScoutRace (FKG Dentaire, La Chaux-de-Fonds, Switzerland) glide path files which were either new or previously used. Forty PathFile (PF) 19/.02 and 40 ScoutRace (SR) 20/.02 instruments were used for this study. Half of the files in each group were used (PF-U and SR-U) in the 3D demo tooth models (FKG Dentaire, La Chaux-de-Fonds, Switzerland) for creating glide paths, while the other half was new (PF-N and SR-N) and directly subjected to the cyclic fatigue test. The new and used files (n=80) were rotated in the cyclic fatigue test device with an artificial stainless-steel canal (60° curvature, 5 mm radius 1.5 mm width and 3.0 mm depth) under the continuous irrigation with distilled water at 37°C until fracture occurred. Time to fracture was recorded and the Weibull reliability analysis was performed. Data were statistically analysed. Conformity to normal distribution was examined using the Shapiro-Wilk test. A paired two-sample t-test was used to compare the TTF values according to the time within the groups. The new instruments (PF-N and SR-N) showed better CFR than the used groups (PF-U and SR-U) (P SR-N>PF-U>SR-U. Reuse of both glide path instruments reduced the time to fracture and the cyclic fatigue resistance of the files.


RESUMEN: El objetivo de este estudio fue comparar la resistencia a la fatiga cíclica (CFR en inglés) de las limas PathFile (Dentsply Sirona, Ballaigues, Suiza) y ScoutRace (FKG Dentaire, La Chaux-de-Fonds, Suiza) de tipo glide path, nuevas o ya previamente utilizadas. Para este estudio se utilizaron 40 instrumentos PathFile (PF) 19/.02 y 40 ScoutRace (SR) 20/.02. La mitad de las limas de cada grupo se utilizaron (PF-U y SR-U) en los modelos dentales de demostración 3D (FKG Dentaire, La Chaux-de- Fonds, Suiza) para crear trayectorias de deslizamiento, mientras que la otra mitad se utilizaron nuevas directamente a la prueba de fatiga cíclica (PF-N y SR-N). Las limas nuevas y usadas (n=80) se hicieron girar en el dispositivo de prueba de fatiga cíclica con un canal artificial de acero inoxidable (curvatura de 60°, radio de 5mm, anchura de 1,5mm y profundidad de 3,0mm) bajo irrigación continua con agua destilada a 37°C hasta que se produjo la fractura. Se registró el tiempo hasta la fractura y se realizó el análisis de fiabilidad de Weibull. Los datos se analizaron estadísticamente. La conformidad con la distribución normal se examinó mediante la prueba de Shapiro- Wilk. Se utilizó una prueba t de dos muestras pareadas para comparar los valores de TTF según el tiempo dentro de los grupos. Los instrumentos nuevos (PF-N y SR- N) mostraron una mejor CFR que los grupos previamente utilizados (PF-U y SR-U) (p SR-N >PF-U >SR-U. La reutilización de ambos instrumentos tipo glide path redujo el tiempo hasta la fractura y la resistencia a la fatiga cíclica de las limas.


Subject(s)
Equipment Reuse , Dental Instruments
3.
Belo Horizonte; s.n; 2020. 83 p. ilus, tab.
Thesis in Portuguese | BBO, LILACS | ID: biblio-1253965

ABSTRACT

As características geométricas e técnicas de fabricação das limas endodônticas afetam o desempenho clínico e sua resistência à fratura, flexibilidade e outras propriedades. Um parâmetro muito explorado na Endodontia é a utilização de tratamentos térmicos, que promovem um aumento na resistência à fadiga e flexibilidade destes materiais. Neste estudo pretendeu-se avaliar o efeito de diferentes processos de tratamento térmico/usinagem nas propriedades físicas, flexibilidade, resistência torcional e à fadiga flexural dos instrumentos Prodesign Logic (PDL), verificando se a sequência de processamento dos instrumentos levaria a comportamentos mecânicos diferentes. Este sistema é fabricado a partir de um método inovador que envolve a realização do tratamento térmico para obtenção de memória de forma no fio NiTi anteriormente à usinagem. A hipótese nula a ser testada é que o momento de aplicação dos procedimentos de tratamento térmico e usinagem não afetariam as propriedades físicas e mecânicas de instrumentos endodônticos de NiTi. Para grupos de comparação, foram utilizados protótipos de instrumentos com as mesmas características geométricas e dimensionais, sendo um grupo de instrumentos sem tratamento térmico aplicado (SEP) e outro com o tratamento térmico realizado de forma convencional, após a usinagem do instrumento (HTP). Foram realizadas caracterização física e microestrutural com ensaios de calorimetria exploratória diferencial (DSC) e testes de difratometria de Raios-X (DRX), além de ensaios mecânicos divididos em testes de torção, dobramento em 45 e resistência à fadiga flexural. Os resultados mostraram que macroscopicamente não houve nenhuma alteração importante nas características dos três grupos de instrumentos, exceto mudanças de cor devido a diferentes sequências de processamento. Os resultados de DSC mostraram que à temperatura ambiente a liga é principalmente austenítica no grupo SEP e que após o tratamento térmico realizado nos grupos PDL e HTP, houve uma mudança nas temperaturas de transformação, com um aumento da temperatura de Af e predominância da liga NiTi em fase R. Os resultados de XDR confirmaram os achados do DSC. As diferenças nos parâmetros medidos entre diferentes tipos de instrumentos nos ensaios de resistência torcional, dobramento a 45º e fadiga flexural foi sempre considerada com um nível de significância de 95%. Os resultados para os ensaios de flexão mostraram que o grupo HTP mostrou-se o mais flexível, com os mais baixos valores de momento de dobramento, seguido por PDL e SEP. Nos resultados dos ensaios de torção foi possível observar que SEP apresentou valores mais altos de torque seguido por PDL e HTP (p<.05). Os ensaios de resistência à fadiga mostraram valores médios de NCF maiores para HTP, seguido por PDL e SEP. Entretanto, um pior comportamento do PDL só seria evidenciado clinicamente se os instrumentos fossem usados um número de vezes maior do que o recomendado pelo fabricante. Pode-se concluir que alterar o processo de fabricação dos instrumentos endodônticos, invertendo-se as etapas de usinagem e tratamento térmico, levou, de fato, a uma mudança no comportamento mecânico de instrumentos Prodesign Logic em relação aos prótótipos.


The geometric characteristics and manufacturing techniques of endodontic instruments affect clinical performance, fracture resistance, flexibility and other properties. A parameter widely explored in Endodontics is the use of heat treatments, which promote an increase in the resistance to fatigue and flexibility of these materials. This study aimed to evaluate the effect of different heat treatment / machining processes on the physical properties, flexibility, torsional strength and flexural fatigue of Prodesign Logic (PDL) instruments, verifying whether the processing sequence of the instruments would lead to different mechanical behaviors. This system is manufactured using an innovative method that involves performing thermal treatment to obtain shape memory in the NiTi wire prior to machining. The null hypothesis to be tested is that the moment of application of the heat treatment and machining procedures would not affect the physical and mechanical properties of NiTi endodontic instruments. For comparison groups, instrument prototypes with the same geometric and dimensional characteristics were used, being one group of instruments without thermal treatment applied (SEP) and another with thermal treatment carried out in a conventional manner, after machining the instrument (HTP). Physical and microstructural characterization were performed with differential scanning calorimetry (DSC) tests and X-ray diffractometry (XRD) tests, in addition to mechanical tests divided into torsion tests, 45° bending and resistance to flexural fatigue. The results showed that macroscopically there were no major change in the characteristics of the three groups of instruments, except for color changes due to different processing sequences. The DSC results showed that at room temperature the alloy is mainly austenitic in the SEP group and that after the heat treatment carried out in the PDL and HTP groups, there was a change in the transformation temperatures, with an increase in the Af temperature and predominance of the NiTi alloy in phase R. The XRD results confirmed the DSC findings. Differences in the parameters measured between different types of instruments in the tests of torsional resistance, bending at 45º and flexural fatigue were always considered with a significance level of 95%. The results for the flexibility tests showed that the HTP group proved to be the most flexible, with the lowest values, followed by PDL and SEP. In the results of the torsion tests it was possible to observe that SEP presented higher values of torque followed by PDL and HTP (p <.05). Fatigue resistance tests showed higher mean NCF values for HTP, followed by PDL and SEP. However, a worse behavior of the PDL would only be evidenced clinically if the instruments were used several times greater than that recommended by the manufacturer. It can be concluded that changing the manufacturing process of endodontic instruments, inverting the machining and heat treatment steps, led, in fact, to a change in the mechanical behavior of Prodesign Logic instruments in relation to the prototypes.


Subject(s)
Calorimetry , Dental Instruments , Endodontics/instrumentation , Tensile Strength , Pliability
4.
Journal of Practical Stomatology ; (6): 260-264, 2018.
Article in Chinese | WPRIM | ID: wpr-697498

ABSTRACT

Objective: To study the effect of the modified preparation method with root canal flushing of different solutions on the anti-fracture properties of mechanical nickel-titanium filings. Methods: A transparent resin model of root canal was established. ProTaper Universal (PTU F1) instrument was used to prepare the root canals. The number of prepared root canals by each PTU F1 with the various solutions(n = 20) was recorded and compared among groups. Results: 6. 13 ± 3. 52 root canals were prepared in distilled water group, 6. 25 ± 1. 76 in 0. 9%saline group, 6. 27 ± 2. 07 of 0. 2% chlorhexidine group, 6. 88 ± 3. 21 in 1% sodium hypochlorite group, 4. 31 ± 2. 34 in 5% sodium hypochlorite group and 3. 26 ± 2. 08 in dry drilling group. The number between each 2 of distilled water, 0. 9%saline group, 0. 2%chlorhexidine group and 1% sodium hypochlorite group, and the number between 5% sodium hypochlorite group and dry drilling group was not statistically significant(P> 0. 05). The number of prepared root canals in the first 4 groups was more than that in the latter 2 groups(P< 0. 05). Conclusion: Distilled water, 0. 9% saline, 0. 2% chlorhexidine or 1% sodium hypochlorite for root canal irrigation can improve mechanical nickel-titanium instrument for fatigue resistance in root canal preparation, but 5% sodium hypochlorite and dry drilling can not.

5.
Braz. dent. j ; 27(4): 452-457, July-Aug. 2016. tab, graf
Article in English | LILACS | ID: lil-794605

ABSTRACT

Abstract The aim of this study was to compare the fatigue resistance of restored teeth with bulk fill composite resin, conventional composite resin with incremental insertion and unprepared sound teeth. Twenty-eight extracted maxillary premolars were selected and divided into 4 groups based on composite resin and insertion technique: control (C), conventional composite resin with incremental insertion (I) and bulk fill composite resin with three (BF3) or single increment (BF1). The restored specimens were submitted to fatigue resistance test with a 5 Hz frequency. An initial application of 5,000 sinusoidal load cycles with a minimum force of 50 N and a maximum force of 200 N was used. Next, were applied stages of 30,000 load cycles with the maximum force increasing gradually: 400, 600, 800, 1000, 1200 and 1400 N. The test was concluded when 185,000 load cycles were achieved or the specimen failed. The fatigue resistance data were recorded for comparison, using the Kaplan-Meier survival curve and analyzed by log-rank test at 0.05 significance. Fractures were classified based on the position of the failure - above or below the cementoenamel junction (CEJ). Statistical analysis of the Kaplan-Meier survival curve and log-rank test showed a significant difference between groups (p=0.001). The fracture analysis demonstrated that only 28.58% of failures were below the CEJ in group C, while for groups I, BF1 and BF3 they were 42.85%, 85.71% and 85.71%, respectively. Teeth restored with composite bulk fill in both techniques present similar fatigue resistance values compared with those restored with a conventional incremental insertion of composite, while the fatigue strength values of unprepared sound teeth were higher. Furthermore, unprepared sound teeth showed a lower percentage of fractures below the CEJ.


Resumo O objetivo deste estudo foi comparar a resistência à fadiga de dentes restaurados com uma resina composta bulk fill, resina composta convencional de inserção incremental e dentes hígidos sem preparo. Vinte e oito pré-molares maxilares extraídos foram selecionados e divididos em quatro grupos conforme a resina composta e técnica de inserção: controle (C), resina composta convencional com inserção incremental (I) e resina composta bulk fill inserida em três (BF3) ou único incremento (BF1). O preparo das cavidades foi padronizado para todos os grupos. As amostras foram restauradas e submetidas ao testes de resistência à fadiga com uma frequência de 5 Hz. Foram aplicados 5.000 ciclos de carregamento senoidal inicial com valor de força mínima igual a 50 N e força máxima de 200 N. Após, foram aplicados estágios de 30.000 ciclos de carga com a força máxima sendo aumentada gradativamente a cada estágio, para 400, 600, 800, 1000, 1200 e 1400 N. O ensaio foi finalizado ao ser alcançado 185.000 ciclos de carga (número máximo de ciclos de carga), ou na fratura da amostra. A resistência à fadiga foi registrada para comparação usando a curva de sobrevivência de Kaplan-Meier e analisada pelo teste log-rank a um nível de significância de 0.05. As fraturas foram classificadas conforme a posição da falha - acima ou abaixo da junção cemento esmalte (JCE). A análise estatística da curva de sobrevivência de Kaplan-Meier pelo teste log-rank demonstrou diferença significativa entre os grupos (p=0.001). Na análise de fratura somente 28.58% das falhas foram abaixo da JCE para o grupo C, enquanto para os grupos I, BF1 e BF3 foram 42.85%, 85.71% e 85.71%, respectivamente. Os dentes restaurados com a resina composta bulk fill em ambas as técnicas de inserção apresentaram valores de resistência à fadiga similares àqueles dos dentes restaurados com a resina composta convencional pela técnica incremental. Entretanto, dentes hígidos mostraram uma menor porcentagem de fraturas abaixo da JCE e maior resistência à fadiga.


Subject(s)
Humans , Materials Testing , Tooth
6.
Article in English | IMSEAR | ID: sea-178117

ABSTRACT

Objective: The objective of this study is to compare the cyclic fatigue resistance of nine types of endodontic instruments of nickel–titanium. Materials and Methods: Five files of 25 mm of length of each group: Reciproc (RC) R25; WaveOne (WO) Primary; Unicone (UC) L25 25/0.06; K3XF 25/0.06; ProTaper Universal F2 (PTF2); ProTaper Next X2 (PTX2); Mtwo 25/0.06; BioRaCe 25/0.06; One Shape L25 25/0.06 were subjected to a cyclic fatigue resistance test on a mechanical apparatus. The mean fracture time was analyzed statistically by one-way analysis of variance and Tukey’s honest significant difference post hoc test, with significance set at P < 0.05. Conclusion: It was observed that the groups PTX2, RC, R25, UC L25 25/0.06, and WO Primary presented greater cyclic fracture resistance than the other groups (P < 0.001).

7.
Article in English | IMSEAR | ID: sea-159381

ABSTRACT

Management of class II malocclusion in adolescents by growth modulation is one of the most difficult and commonly encountered scenario in clinical orthodontics. Noncompliance has been a major concern for orthodontists. This case report describes the management of class II malocclusion in young adult with Forsus fatigue resistance device (3M Unitek, 2724 S., Peck Road, Monrovia, CA 91096; www.3Munitek.com), a fixed functional appliance, that is now most widely used for correction of Class II malocclusion. A common problem with this appliance is frequent debonding of mandibular canine brackets. The present article also describes a simple, chairside fabrication of acrylic button that will ensure prevention of debonding of brackets. This case report illustrates that functional appliances even today have a significant role in growth modulation that further minimizes the necessity of extraction of permanent teeth and orthognathic surgery.


Subject(s)
Female , Humans , Malocclusion, Angle Class II/epidemiology , Malocclusion, Angle Class II/surgery , Malocclusion, Angle Class II/therapy , Mandible/growth & development , Orthodontic Appliances, Functional , Orthodontic Appliance Design/methods , Young Adult
8.
ROBRAC ; 22(63)out.-dez. 2013. tab, ilus
Article in Portuguese | LILACS | ID: lil-737225

ABSTRACT

Objetivo: Comparou o tempo de preparo, ocorrência de fratura e manutenção do trajeto do canal em canais artificiais do instrumento Reciproc R25 em movimento reciprocante e rotação contínua anti-horária. Material e Métodos: Foram utilizados dois grupos contendo 10 canais artificiais em blocos de acrílico cada, sendo um o grupo controle, instrumentado com movimento reciprocante, e o grupo teste utilizando rotação contínua anti-horária a 300rpm para a instrumentação. Resultados: os resultados mostraram que houve diferença estatística significante em relação ao tempo de preparo entre os grupos, uma vez que a rotação contínua anti-horária proporcionou um menor tempo de preparo; ambos mantiveram o trajeto original do canal sem qualquer desvios no terço apical e ocorreu uma fratura no grupo da rotação contínua. Conclusão: o sistema Reciproc manteve a trajetória original do canal, não influenciou na incidência de fratura dos instrumentos e demandou menor tempo de preparo utilizando rotação contínua. Portanto, o sistema Reciproc pode ser utilizado com rotação contínua anti-horária desde que velocidade, torque e pressão apical sejam respeitados e se empregue os instrumento uma única vez.


Objective: This study aimed to compare the preparation time, occurrence of fracture and maintenance of the canal path in artificial canals using Reciproc R25 instrument moving reciprocating and continuous counterclockwise rotation. Methods: Two groups of 10 Simulated rootcanals, each one in an artificial acrylic block, was instrumented with reciprocating motion (control group) and using counterclockwise continuous rotation to 300rpm (test group). Results: The results showed statistically significant difference in relation to the preparation time between the groups, since the counterclockwise continuous rotation allowed shorter preparation time, both kinematics kept the original route of the canal without any deviations in the apical third. A fracture occurred in the group of continuous rotation. Conclusion: The Reciproc system kept the original trajectory of the canals and did not influence the incidence of instruments fracture. A less preparation time was required when the continuous rotation was used. Therefore, the Reciproc system can be used with counterclockwise continuous rotation since that speed, torque and apical pressure are respected. The instrument also should be employed just one time.

9.
Chinese Journal of Tissue Engineering Research ; (53): 5607-5612, 2013.
Article in Chinese | WPRIM | ID: wpr-433732

ABSTRACT

BACKGROUND:The mechanical valves used in the adult Luo-Ye pump have a large size and great destruction to blood, which are not suitable for infant ventricular assist pump. Therefore, designing and producing a high molecular valve with smal size and low incidence of thrombosis is a research hotspot. OBJECTIVE:To design and produce a valve of 20 mL infant Luo-Ye pump, and to test its basic functions and fatigue properties. METHODS:The size and shape of valve was designed with MASTERCAM software, polyurethane valve was obtained through producing the valve model and plastic injection;the static leakage, pressure drop and fatigue resistance of polyurethane valve were tested according to the ISO5840 requirements. RESULTS AND CONCLUSION:The polyurethane trefoil valve was produced, but the failure rate of plastic injection was high;the basic function of the trefoil valve met the ISO5840 requirements bascial y;after continuously operated 1.0×107 times, stroke volume of 20 mL Luo-Ye pump was changed 5.2%, and two polyurethane valves and valve leaflets did not change and damage. Polyurethane trefoil valve was designed and produced successful y;polyurethane valves could meet the needs of 20 mL Luo-Ye pump, which already have the ability to clinical trials.

10.
Article in English | IMSEAR | ID: sea-174083

ABSTRACT

Growing skeletal class II malocclusions with mandibular deficiency have been treated for more than a century with different types of functional appliances. Removable or fixed functional appliances are available to advance the mandible. Fixed functional appliances have the advantage of not requiring patient compliance. They can also be used concurrently with brackets. This case report documents the successful treatment of mild skeletal class II in late stages of puberty by using Forsus fatigue resistance appliance. The Forsus appliance is a three-piece, semi-rigid telescoping system incorporating a super-elastic nickel -titanium coil spring that can effectively brings the mandible forward in a relatively shorter treatment time. It is compatible with complete fixed orthodontic appliances and can be incorporated into preexisting appliances.

11.
Chinese Journal of Rehabilitation Theory and Practice ; (12): 492-494, 2010.
Article in Chinese | WPRIM | ID: wpr-960665

ABSTRACT

@#ObjectiveTo study the method of testing abrasion resistance of axillary crutch tips. MethodsA test method based on pressure analysis in normal use of axillary crutches was suggested, which characterized: put 450 N on axis of the tip; the tip or text surface sway 60° for 500000 times in frequency of 40 /min; maximal abrasion thickness after test should be less than 3.3 mm. Experimental facilities were established to carry out fatigue test of wearability. ResultsThe test method suggested can reflect tips abrasion in real context. ConclusionThe text method can be used for tips abrasion and fatigue resistance adjustment.

12.
Journal of Korean Academy of Conservative Dentistry ; : 424-429, 2009.
Article in English | WPRIM | ID: wpr-31982

ABSTRACT

This study aimed to assess the influence of different cross-sectional area on the cyclic fatigue fracture of Ni-Ti rotary files using a fatigue tester incorporating cyclical axial movement. Six brands of Ni-Ti rotary files (ISO 30 size with .04 taper) of 10 each were tested: Alpha system (KOMET), HeroShaper (MicroMega), K3 (SybronEndo), Mtwo (VDW), NRT (Mani), and ProFile (Dentsply). A fatigue-tester (Denbotix) was designed to allow cyclic tension and compressive stress on the tip of the instrument. Each file was mounted on a torque controlled motor (Aseptico) using a 1:20 reduction contra-angle and was rotated at 300 rpm with a continuous, 6 mm axial oscillating motion inside an artificial steel canal. The canal had a 60degrees angle and a 5 mm radius of curvature. Instrument fracture was visually detected and the time until fracture was recorded by a digital stop watch. The data were analyzed statistically. Fractographic analysis of all fractured surfaces was performed to determine the fracture modes using a scanning electron microscope. Cross-sectional area at 3 mm from the tip of 3 unused Ni-Ti instruments for each group was calculated using Image-Pro Plus (Imagej 1.34n, NIH). Results showed that NRT and ProFile had significantly longer time to fracture compared to the other groups (p < .05). The cross-sectional area was not significantly associated with fatigue resistance. Fractographycally, all fractured surfaces demonstrated a combination of ductile and brittle fracture. In conclusion, there was no significant relationship between fatigue resistance and the cross-sectional area of Ni-Ti instruments under experimental conditions.


Subject(s)
Electrons , Fatigue , Fractures, Stress , Nickel , Radius , Steel , Titanium , Torque
13.
The Journal of Korean Academy of Prosthodontics ; : 780-786, 2007.
Article in English | WPRIM | ID: wpr-45791

ABSTRACT

STATEMENT OF PROBLEM: The performance and maintenance of implant-supported prostheses are primarily dependent upon load transmission both at the bone-to-implant interface and within the implant-abutment-prosthesis complex. The design of the interface between components has been shown to have a profound influence on the stability of screw joints. PURPOSE. The Purpose of this study was to compare the strength and the fatigue resistance of 1-piece and 2-piece abutment connected to oral implant, utilizing an internal conical interface. MATERIAL AND METHODS: Twenty Implatium(R) tapered implants were embedded to the top of the fixture in acrylic resin blocks. Ten Combi(R)(1-piece) and Dual(R)(2-piece) abutments of the same dimension were assembled to the implants, respectively. The assembled units were mounted in a testing machine. A load was applied perpendicular to the long axis of the assemblies and the loading points was at the distance of 7mm from the block surface. Half of 1-piece and 2-piece abutment-implant units were tested for the evaluation of the bending strength, and the others were cyclically loaded for the evaluation of the fatigue resistance until plastic deformation occurred. Nonparametric statistical analysis was performed for the results. RESULTS: Mean plastic and maximum bending moment were 1,900+/-18Nmm, 3,609+/-106Nmm for the 1-piece abutment, and 1,250+/-31Nmm, 2,688+/-166Nmm for the 2-piece abutment, respectively. Mean cycles and standard deviation when implant-abutment joint showed a first plastic deformation were 238,610+/-44,891. cycles for the 1-piece abutment and 9,476+/-3,541 cycles for the 2-piece abutment. A 1-piece abutment showed significantly higher value than a 2-piece abutment in the first plastic bending moment (P<.05), maximum bending moment (P<.05) and fatigue strength (P<.05). CONCLUSION: Both 1-piece and 2-piece conical abutment had high strength and fatigue resistance and this suggests long-term durability without mechanical complication. However, the 1-piece conical abutment was more stable than the 2-piece conical abutment in the strength and the fatique resistance.


Subject(s)
Axis, Cervical Vertebra , Fatigue , Joints , Plastics , Prostheses and Implants
14.
The Journal of Korean Academy of Prosthodontics ; : 734-739, 2006.
Article in English | WPRIM | ID: wpr-109147

ABSTRACT

STATEMENT OF PROBLEM: Many surface processing methods of dental implant have been developed, the laser processing is one of them. PURPOSE: This study was to investigate in vitro the fatigue resistance of implants treated with laser method(CSM implant, CSM Company, Daegu, Korea). MATERIAL AND METHODS: Fatigue tests of 23 laser treated CSM implant(CSM Company, Daegu, Korea) were conducted using Instron 8871 (Load cell, 5 kN, Instron Co., England), according to ISO 14801 (2003), RESULTS: From 300 N, each specimens were not fractured and withstood until more than 5,000,000 cycle. CONCLUSION: Within the limits of this in vitro study, implants treated with laser method (CSM implant, CSM Company, Daegu, Korea) have had enough rigidity and fatigue resistance to use clinically with reliance.


Subject(s)
Dental Implants , Fatigue
15.
Journal of Xi'an Jiaotong University(Medical Sciences) ; (6)2003.
Article in Chinese | WPRIM | ID: wpr-546969

ABSTRACT

Objective To investigate the effect of maple syrup on fatigue resistance in mice. Methods Totally forty Kunming mice were divided randomly into normal control group, low-dose maple syrup group (1.25g/kg), medium-dose maple syrup group (2.50g/kg), and high-dose maple syrup group (5.00g/kg). Mice were continuously given water and maple syrup through mouth for 30 days. Various groups swam for 10min. The contents of blood lactic acid were measured at swimming 0min, 10min and resting 30min. The contents of hemoglobin, blood lactic acid, serum urea nitrogen, muscle glycogen, and liver glycogen of various group mice were detected after resting 30min. Results The content of serum urea nitrogen of three maple syrup groups was less than that in normal control group (P

16.
Medical Journal of Chinese People's Liberation Army ; (12)2001.
Article in Chinese | WPRIM | ID: wpr-562230

ABSTRACT

Objective To study in clinic the potential antifatigue effect of red-light irradiation onto the soldiers exhausted by a high intensity of exercise with detection of myocardial enzymes, coagulation indices and other blood routines before and after the bio-light therapy. Methods 200 soldiers selected were assigned averagely and randomly into two groups, test group and control group, with 100 for each group. All the volunteers underwent a strong intensity and exhaustion exercise. Then the red-light irradiation of 30J/cm2?30 min once a day performed 2 weeks was given to the soldiers in test group, and the soldiers in control group received similar treatment except that daylight lamp was employed instead of red-light irradiation. The blood samples were then collected from all the volunteers before the exercise and 7d and 14d after the exercise for detecting and comparing the indexes of aspartate transaminase (AST), lactate dehydrogenase (LDH), creatine kinase (CK), creatine kinase MB isoforms (CK-MB), Hydroxybutyric dehydrogenase (HBDH), white blood cell (WBC), hemoglobin (HB), red blood count (RBC), platelet (PLT), prothrombin time (PT), activated partial thromboplastin time (APTT), plasma fibrinogen (FIB), thrombin time (TT) and calcium (Ca2+). Results The findings showed an obvious increase in the indices of HB, RBC and Ca2+ of the soldiers in the test group, the indices were significantly higher than that of the soldiers in the control group. However, no significant difference was found between the two groups in such indices as AST, ADH, CK, CK-MB, HBDH, WBC, PLT, PT, APTT, FIB and TT. Conclusion As one of the harmless biotherapies, red light irradiation is conveniently and easily applied for restoring the exhausted soldiers to their normal physical ability. Without side-effects, the red light irradiation may improve the antifatigue and endurance capacity after an individual underwent a strong intensity and exhaustion exercise. It′s valuable and acceptable for enhancement of soldiers′ combat capabilities.

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