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Resumen Antecedentes. La resistencia a la fractura de las coronas puede tener influencia en su ocurrencia, de acuerdo con el método de fabricación usado, ya sea análogamente o por medio de tecnología Cad-Cam. Objetivo. Comparar la resistencia a la fractura de las coronas individuales realizadas por dos métodos de fabricación, bajo diseño asistido por ordenador y fabricación computarizada (CAD-CAM) e inyectadas. Método. Estudio in vitro. Tamaño de la muestra 20 coronas en dos grupos: 10 coronas bajo tecnología CAD-CAM y 10 coronas inyectadas. Fueron sometidas a cargas compresivas en una máquina de ensayos universal, con una velocidad de 1mm/min y una carga de celda de 5kN hasta obtener la fractura máxima de estas. Los datos se analizaron estadísticamente utilizando las pruebas Shapiro Wilk, Mann Whitney p=0,05. Resultados. Las coronas fabricadas por Cad-Cam obtuvieron un mínimo de 602,5 Newton y un máximo de 1093 Newton, mientras que las coronas fabricadas análogamente obtuvieron un mínimo de 525,2 Newton y un máximo de 1773 Newton en el experimento con la máquina de ensayo universal para lograr su fractura. Se obtuvo una diferencia significativa en la prueba de resistencia a la factura entre ambos métodos de fabricación (p <0,001). Conclusión. Las coronas de Disilicato de litio Prensadas obtuvieron una mayor resistencia a la fractura que las coronas fabricadas via CAD-CAM.
Abstract Background. The fracture resistance of the crowns may have an influence on their appearance, according to the method of making them, either analogously or by means of Cad-Cam technology. Objective. To compare the resistance to the fracture of the individual crowns made by two manufacturing methods, under computer-aided design and computerized manufacturing (CAD-CAM) and injected. Methods. In vitro study. Sample size 20 crowns in two groups: 10 crowns using CAD-CAM technology and 10 crowns injected. Crowns were subjected to compressive loads in a universal testing machine, with a speed of 1mm / min and a cell load of 5kN until obtaining the maximum bill for these. Data were statistically analyzed using the Shapiro Wilk tests, Mann Whitney p = 0.05. Results. Crowns manufactured by Cad-Cam obtained a minimum of 602.5 Newton and a maximum of 1093 Newton, while the crowns manufactured analogously obtained a minimum of 525.2 Newton and a maximum of 1773 Newton in the experiment with the machine Universal test to achieve their fracture. A significant difference was obtained in the invoice resistance test between both manufacturing methods (p <0.001). Conclusion. Pressed Lithium Disilicate crowns obtained higher fracture resistance than crowns under design and manufacturing by computer (CAD-CAM).
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Humans , Crowns , Computer-Aided Design , Fractures, Bone , Flexural StrengthABSTRACT
El objetivo de esta investigación fue analizar los ángulos de convergencia en preparaciones dentarias para coronas realizadas en tipodontos, por estudiantes de décimo semestre de Odontología Unach. Las preparaciones dentales para coronas poseen características de retención y resistencia, principios fundamentales que ofrecen éxito y longevidad de la corona definitiva. Varios investigadores a nivel mundial han desarrollado diversos métodos para evaluar los ángulos de convergencia de las preparaciones extracoronarias; sin embargo, en nuestro medio, no existen estudios acerca de la medición de estos ángulos. Esta investigación fue de carácter experimental, transversal y observacional, se obtuvieron 32 preparaciones dentarias para coronas de recubrimiento completo, cada estudiante tuvo 60 minutos para tallar dos preparaciones dentarias en simuladores clínicos. Los tipodontos fueron escaneados y digitalizados mediante el escáner CAD-CAM Ceramill Database versión 1.0 año 2010 del Laboratorio "BrothersDent" para producir imágenes tridimensionales. El software iTero midió los ángulos vestíbulo-lingual (VL) y mesio-distal (MD) de cada preparación. Los ángulos más pequeño y más grande observados fueron 3.1° y 102.5° para molares mandibulares. El promedio del ángulo VL para dientes anteriores fue 40,38 ±4,38° en varones y 36,97 ±3,95° en mujeres y el promedio del ángulo MD fue 44,68 ±5,51° en varones y 40,08 ±3,99° en mujeres. Para dientes posteriores el promedio VL fue 27,46 ±7,82° en varones y 40,98 ±4,63° en mujeres; y el promedio del ángulo MD fue 40,73 ±5,95° en varones y 50,62 ±7,00° en mujeres. En conclusión, los ángulos de convergencia logrados por estudiantes fueron mayores que los ideales recomendados según Shillingburg.
This research aimed to analyze the angles of convergence in dental preparations for crowns performed on typodont, by 10th semester students of school of dentistry, UNACH. Dental preparations for crowns have retention and resistance characteristics, fundamental principles that offer success and longevity of the final crown. Various researchers worldwide have developed various methods to evaluate the convergence angles of extra coronary preparations; however, in our context, there are no studies on the measurement of these angles. This research was experimental, cross-sectional and observational, 32 dental preparations were obtained for fully covered crowns, each student had 60 minutes to carve two dental preparations in clinical simulators. The typodonts were scanned and digitized using the scanner CAD-CAM Ceramill Database version 1.0 - 2010 of "BrothersDent" Laboratory in order to produce three-dimensional images. The iTero software measured the vestibule-lingual (VL) and mesio-distal (MD) angles of each preparation. The smallest and largest angles observed were 3.1 ° and 102.5 ° for mandibular molars. The mean VL angle for anterior teeth was 40.38 ± 4.38 ° in males and 36.97 ± 3.95 ° in females, and the mean MD angle was 44.68 ± 5.51 ° in males and 40, 08 ± 3.99 ° in women. For posterior teeth the average VL was 27.46 ± 7.82 ° in men and 40.98 ± 4.63 ° in women; and the mean MD angle was 40.73 ± 5.95 ° in men and 50.62 ± 7.00 ° in women. In conclusion, the convergence angles achieved by students were greater than the recommended ideals according to Shillingburg.
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Humans , Male , Female , Adult , Computer-Aided Design , Crowns , Molar , Research , Students, Dental , ToothABSTRACT
Objective@#To explore the application value of non-flapping technique in immediate implant prosthesis in aesthetic area of anterior teeth.@*Methods@#From March 2016 to September 2017, 104 patients who received immediate implant restoration of anterior teeth in the First Hospital of Jiaxing were divided into observation group (53 cases) and control group (51 cases) according to random number table method.The control group was treated with conventional flap immediate implantation, while the observation group was treated with non-flap immediate implantation.The red aesthetic index (EPS), alveolar bone resorption and patients' satisfaction were compared between the two groups.@*Results@#The PES scores of the observation group were (6.17±1.21)points, (5.94±1.03)points and (5.12±0.85)points, respectively after repair 3 months, 6 months and 12 months, which were significantly higher than those of the control group [(5.38±0.96)points, (4.79±0.76)points, (4.05±0.70)points] (t=3.679, 6.459, 6.993, all P<0.05). At 3 months, 6 months and 12 months after restoration, the alveolar bone resorption in the observation group was(0.29±0.04)mm, (0.63±0.12)mm, (1.07±0.17)mm, respectively, which was significantly lower than that in the control group [(0.36±0.07)mm, (0.95±0.24)mm, (1.28±0.26)mm] (t=6.291, 8.649, 4.893, all P<0.05). At 12 months after repair, the satisfaction rate of patients in the observation group was 98.11% (52/53), which was significantly higher than 84.31% (43/51) in the control group (χ2=4.637, P<0.05).@*Conclusion@#The application of non-flapping technique in immediate implant prostheses in aesthetic area of anterior teeth has good effect, which can obtain better aesthetic effect, reduce alveolar bone absorption and improve patients'satisfaction with prostheses.However, in clinical work, it is necessary to strengthen preoperative examination and measurement of patients, accurately grasp the direction of implants and avoid the occurrence of bone wall perforation during operation.
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BACKGROUND:Titanium zirconium niobium tin al oy (Ti-Zr-NB-Sn al oy) has good tissue structure, mechanical properties, corrosion resistance and biocompatibility, which is an ideal dental material. OBJECTIVE:To explore the efficacy and safety of Ti-Zr-NB-Sn al oy in dental restoration. METHODS:A retrospective analysis was performed on clinical data of 87 cases of dental defects, including 43 males and 44 females, aged 22-41 years. Of the 87 cases, 43 cases were repaired with Ti-Zr-NB-Sn al oy as observation group, and the other 44 cases were treated with nichrome as control group. After 36 months of fol ow-up, the therapeutic efficacy, dental restoration conditions, dental prosthesis conditions and patient satisfaction were observed and compared. RESULTS AND CONCLUSION:Al the 87 patients were fol owed up for 36 months. After the fol ow-up, the total effective rate and patient satisfaction were higher in the observation group than the control group (P<0.05). In the control group, there were four cases of swol en gums, four cases of bleeding gums, four cases of al ergies, three cases of gum gray line, and six cases of mucosal pain;in the observation group, there was only one case of swol en gums, and the dental restoration was better in the observation group than the control group (P<0.05). For the dental prosthesis, there were 10 cases of dental stent damage and 20 cases of dental stent loosening in the control group;and only one case of dental stent damage and one case of dental stent loosening in the observation, and the observation group was superior to the control group in the dental prosthesis (P<0.05). Experimental findings suggest that Ti-Zr-NB-Sn al oy for repair of dental defects has good biocompatibility and security.
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BACKGROUND:Studies have shown that selection of implant crowns that directly impact the service life of implants and patient’s periodontal health is very important. OBJECTIVE:To compare the clinical effects of Lava zirconia crowns, goal-platinum al oy ceramic crowns and silver-pal adium al oy crowns supplemented by dental implants used in the single missing posterior tooth. METHODS:Sixty patients with first molar missing (120 teeth) were divided into three groups and treated with Lava zirconia, goal-platinum al oy ceramic and silver-pal adium al oy crowns applied to the dental implants for posterior column defects. The clinical restorative effects of three prostheses were compared. RESULTS AND CONCLUSION:During 6-48 months of fol ow-up, the gingival edge coloring, gingival margin microleakage, the color of prosthesis of Lava zirconia al oy ceramic crowns and gold-platinum al oy ceramic crowns were better than those of silver-pal adium al oy crowns, and the gingival edge coloring and the color of prosthesis of Lava zirconia al oy ceramic crowns were better than those of gold-platinum al oy ceramic crowns, while the gingival margin microleakage of gold-platinum al oy ceramic crowns was better than that of Lava zirconia al oy ceramic crowns. Silver-pal adium al oy crowns were lower than Lava zirconia ceramic crowns and gold-platinum al oy ceramic crowns in the fracture extent. But silver-pal adium al oy crowns had the highest gingival index, the worst gingival health and rapidest and most severe plaque formation. Therefore, Lava zirconia al-ceramic crowns and gold platinum al oy-porcelain crown are ideal prostheses for implant restorations. The former has better biocompatibility, and the latter shows better marginal adaptation.
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BACKGROUND:Studies have shown that fiber post is superior to cast metal post in the restoration of large-area dental defects, in prognostic terms of post and core crown off, post and core breakage, root fracture. OBJECTIVE:To explore the application value of glass fiber post and cast metal post in restoration of tooth defects. METHODS:Totaly 100 patients with dental defects (150 teeth; 51 males and 48 females) were selected and randomly divided into observation group (50 cases, 70 teeth) and control group (50 cases, 80 teeth). Al of the patients were treated with glass fiber post and metal post repair. After repair, al the patients were folowed up for 1-3 years. The repair effect of the two groups were observed and compared in terms of integrity, color matching, marginal fit, periodontal pocket depth, alkaline phosphatase activity and post and core crown damage. RESULTS AND CONCLUSION:After 1 year of repair, the observation group was better than the control group in aspects of marginal fit and color matching (P < 0.05); after 1-3 years, the alkaline phosphatase activity was significantly lower in the observation group than the control group (P < 0.05), and there was no difference in the periodontal probing depth between the two groups; while the observation group exhibited higher successful rate than the control group (P < 0.05). The results show that compared with the cast metal post, glass fiber post is better for restoration of tooth defects, exhibiting better restoration effect and long-term success rate, which is conducive to the maintenance of periodontal health.
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A prótese parcial removível instalada sem o preparo prévio da boca tende a se deteriorar precocente além de provocar danos ao aparelho mastigatório. Objetivo: Avaliar a execução do preparo da boca em modelos de trabalhos enviados para laboratórios de próteses dentárias, em cinco cidades do Estado da Paraíba. Material e métodos: Dois examinadores calibrados analisaram 1000 modelos de trabalho e preencheram para cada modelo um formulário com seis itens. Resultados: Revelaram que a arcada superior representou 53,1% da amostra. Com relação à classificação de Kennedy, 33,7% dos modelos pertenciam à classe III, 29,7% à classe I, 28,7% e 7,9% às classes II e IV respectivamente. Noventa e dois por cento da amostra não apresentou qualquer esboço de preparo da boca. Quanto ao material empregado para a obtenção dos modelos, 61% foram confeccionados com gesso tipo IV, 35,6% gesso tipo III e 3,4% gesso tipo II. Conclusões: Concluiu-se que o preparo da boca é realizado com menor frequência nas cidades do interior, mesmo assim o índice de preparo em João Pessoa é muito baixo
Removable partial dentures installed without prior mouth preparation tend to deteriorate prematurely, in addition to causing damage to the masticatory apparatus. Objective: To assess mouth preparation performance on master casts sent to prosthodontics laboratories in five towns located in the state of Paraiba. Materials and method: Two calibrated examiners analyzed 1,000 casts, filling out a six-item form for each cast. Results: Data revealed that the upper teeth represented 53.1% of the sample. As regards Kennedy's classification, 33.7% of the casts were Class III; 29.7% were Class I; 28.7% and 7.9% were Class II and Class IV, respectively. Ninety-two percent of the sample showed no trace of mouth preparation. In relation to the material used to obtain the casts, 61% were prepared using Type IV gypsum; 35.6% used Type III gypsum and 3.4% used Type II gypsum. Conclusion: Mouth preparation has been carried out less frequently in the inner towns, even though preparation rates in the state capital of Paraiba (Joao Pessoa) was found to be very low as well
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Humans , Tooth Preparation, Prosthodontic , Models, Dental , Denture, Partial, RemovableABSTRACT
Objective To explore a positive Ji treatment clinical application and effect before the mouth cavity repairs,analyzing and providing a reference method for positive Ji treatment. Methods To analyze 80 adult's sufferers, all adopt to fixedly correct and cure a machine to correct and cure,match square silk bow or keep silk bow to correct and cure technique and assistance device, the treatment is 7～33 months. Carry on an analysis discussion to the treatment method and effect, clinical characteristics of adult positive Ji at the same time. Results In 80 sufferers,show effect 65 people,have 81.25%;Effective 14 people have 17.5%;Invalid one person has 1.25%.In addition to invalid,the rest sufferer all has better pronunciation and beautiful effect after the positive Ji cures and all have never taken place bad reaction. Conclusion The mouth cavity repairs ex-positive Ji the treatment not only create a condition for repair treatment and promote repair the treatment attain better clinical effect, can also make mouth cavity organize to keep healthy betterly and obviously improve a sufferer the tooth image and noodles permits of beauty.