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1.
Am J Dent ; 36(5): 215-221, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37865807

RESUMEN

PURPOSE: To evaluate the efficacy of COMORAL a new multi-channeled oral irrigation (MCOI) unit with pulsating water jet, in plaque score reduction and gingivitis. METHODS: This was a single-blinded clinical randomized controlled trial (NCT05031260). Forty-two healthy subjects between 18 to 35 years old were initially recruited, and the control group (n = 20) and the intervention group (n = 17) were randomly assigned. Both groups were asked to brush their teeth one or two times a day without any supplementary oral hygiene products while the intervention group used COMORAL 3 times a day, 5 days a week. Clinical indices including gingival index (GI), plaque index (PI), bleeding on probing (BOP), pocket depth (PD), gingival recession (GR), and clinical attachment loss (CAL) were obtained at the baseline (D0), day 14 (D14), and day 28 (D28). Saliva was collected to examine the presence of periodontal pathogens. The repeated measures analysis of variance or generalized estimating equation was used to compare the interaction between groups and time points. The independent t-test or Mann-Whitney test were used for intergroup differences at each time point. RESULTS: At V0, PI, GI, BOP, and PD scores showed no differences between the two groups. At V1 and V2, these scores showed significant difference between two groups (P < 0.05) such that the intervention group showed gradual decreases while the control group showed no change. There were no differences in GR, CAL, and periodontal pathogens between the two groups. COMORAL showed improvement in reducing gingival inflammation and dental plaque formation adjuvant to routine toothbrushing in healthy adults. CLINICAL SIGNIFICANCE: The results of this study can be useful to clinicians when selecting oral hygiene devices that can help improve patients' routine oral hygiene practice and their overall oral health.


Asunto(s)
Placa Dental , Gingivitis , Adulto , Humanos , Adolescente , Adulto Joven , Placa Dental/prevención & control , Gingivitis/prevención & control , Higiene Bucal , Cepillado Dental , Método Simple Ciego , Índice de Placa Dental
2.
J Prosthet Dent ; 127(2): 239-247, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33246562

RESUMEN

STATEMENT OF PROBLEM: The fit and performance of prostheses fabricated using various computer-aided design and computer-aided manufacturing (CAD-CAM) systems have been evaluated. However, most studies were conducted in vitro, and relatively few have addressed gingival parameters and prosthesis fit under clinical conditions. PURPOSE: This clinical study aimed to compare the fit of lithium disilicate crowns produced using 3 CAD-CAM systems and evaluate clinical results up to 6 months after delivery. MATERIAL AND METHODS: Forty participants requiring a single crown were recruited. Three monolithic lithium disilicate crowns were fabricated per participant by using 3 different CAD-CAM systems (intraoral scanners, CAD software, and milling machines): CEREC group (CEREC Bluecam, CEREC AC, CEREC MC); EZIS group (EZIS PO, EZIS VR, EZIS HM); and TRIOS group (TRIOS 3, EXO-CAD, ARUM-4X). The fit of the prostheses was assessed via a silicone replica technique, and the most acceptable crown was delivered; 12 were selected from the CEREC group, 16 from the EZIS group, and 12 from the TRIOS group. Follow-up clinical examinations were performed at 1, 3, and 6 months after delivery. The Kruskal-Wallis test with the post hoc Mann-Whitney U test was conducted to analyze significant differences in crown fit and periodontal conditions among the groups (α=.05). RESULTS: The marginal gap of the CEREC group was significantly higher than that of the EZIS group, and the occlusal gap of the EZIS group was significantly lower than those of the CEREC and TRIOS groups (P<.05). Probing depth, bleeding index, and plaque index showed no intergroup differences at 6 months (P>.05). CONCLUSIONS: The lithium disilicate crowns of all groups showed clinically acceptable fit. No significant differences were found among the groups in terms of periodontal conditions after 6 months.


Asunto(s)
Adaptación Marginal Dental , Diseño de Prótesis Dental , Diseño Asistido por Computadora , Coronas , Porcelana Dental , Diseño de Prótesis Dental/métodos , Humanos
3.
J Prosthet Dent ; 126(1): 76-82, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32792143

RESUMEN

STATEMENT OF PROBLEM: Implant-assisted removable partial dentures (IARPDs) have been proposed as a treatment option for partially edentulous patients. However, evidence regarding the outcome of implant-assisted removable partial dentures with implant surveyed prostheses is limited. PURPOSE: The purpose of this retrospective clinical study was to evaluate the clinical status and complications of IARPDs combined with implant surveyed prostheses in terms of clinical tissue condition, marginal bone resorption, and prosthetic complications. MATERIAL AND METHODS: Patients treated with IARPDs combined with implant surveyed prostheses who had worn an IARPD for at least 12 months were included. Twenty-four participants (25 prostheses, 12 maxillary, and 13 mandibular) were evaluated, with 80 implants used as abutments for IARPDs. The average follow-up period was 27.6 months, and the maximum follow-up was 78 months. Implant cumulative survival rate, marginal bone resorption, probing depth, peri-implant inflammation, bleeding, plaque, calculus, and complications were evaluated. RESULTS: No implant failure occurred, and all implants functioned without clinical mobility. Mean marginal bone resorption of implants at 1 year after loading was 0.77 ±0.63 mm, and mean probing depth was 3.4 ±0.1 mm. No patient developed peri-implantitis, and no implant failed. Two clasp fractures, 1 rest fracture, 1 decementation, and 1 fracture of porcelain on an implant surveyed prosthesis were detected at 12 months after loading. CONCLUSIONS: Well-planned IARPDs using implant surveyed prostheses were clinically successful. Longitudinal and systematic clinical studies are necessary to confirm these results.


Asunto(s)
Implantes Dentales , Dentadura Parcial Removible , Prótesis Dental de Soporte Implantado , Estudios de Seguimiento , Humanos , Mandíbula , Estudios Retrospectivos , Resultado del Tratamiento
4.
J Prosthodont ; 30(S2): 158-162, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33434330

RESUMEN

PURPOSE: A retrospective study to analyze the clinical performance of 3D printed complete dentures in edentulous patients compared with conventional complete dentures regarding postinsertion visits and patient reported outcomes. MATERIAL AND METHODS: Electronic charts were reviewed to analyze 420 (maxilla 270, mandible 150) heat-polymerized conventional complete dentures (CCD) inserted between July 1, 2015 and June 30, 2016 and 217 (maxilla 130, mandible 86) 3D printed complete dentures (PCD) inserted between July 1, 2017 and June 30, 2018. Number of remakes, number of postinsertion adjustments, type and number of repairs, and patient reported complications were compared between two types of complete dentures. The frequency of denture repair and patient reported complications were analyzed using chi-square of independence test. RESULTS: The frequency of pain and visible ulcer lesions in the maxilla was determined to be 46.67% with CCD and 36.15% in PCD (p = 0.047). There was no statistical significance in other items. The majority of esthetic concerns was dissatisfaction with the shape of dentures with CCD (4.67%) and they had statistically significant, less frequent, esthetic problems than PCD (11.63%) (p = 0.047). CONCLUSIONS: Similar clinical performance was recorded between the two groups, but the overall pain and visible ulcer lesions were less in the printed complete dentures then the conventionally processed dentures. However, the esthetic aspect was better in conventionally processed complete dentures.


Asunto(s)
Dentadura Completa , Estética Dental , Humanos , Mandíbula , Impresión Tridimensional , Estudios Retrospectivos
5.
J Prosthet Dent ; 124(4): 428-430, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31918894

RESUMEN

A custom abutment produced from a digital scan can be used to develop an implant-supported prosthesis with ideal contours. A scan body is used to obtain information about the location of the implant fixture, and the scan body has a special scan region that facilitates superimposition. This dental technique indirectly obtains the margin of the definitive prosthesis by designing the special scan region on a custom abutment and superimposing prescanned abutment data onto intraoral scanned data.


Asunto(s)
Implantes Dentales , Diseño de Prótesis Dental , Diseño Asistido por Computadora , Pilares Dentales , Prótesis Dental de Soporte Implantado , Flujo de Trabajo
6.
J Prosthet Dent ; 123(1): 15-19, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31076165

RESUMEN

A microlocking implant prosthetic system has recently been developed to address the limitations of conventional screw- and cement-retained implant-supported fixed dental prostheses. This prosthesis system consists of a precision-machined abutment and an attachment that includes zirconia balls and a nickel-titanium spring, thus providing retrievability and constant retention of the prosthesis. In addition, screw-related complications are avoided because there is no retention screw. The occlusal access hole is of a smaller diameter than that of conventional screw-retained prostheses, which is beneficial for esthetics and occlusion. It also prevents common complications of cement-retained prostheses because residual cement around the prosthesis can be removed extraorally. This article presents a clinical treatment with this new prosthetic system.


Asunto(s)
Implantes Dentales , Retención de Prótesis Dentales , Cementación , Pilares Dentales , Prótesis Dental de Soporte Implantado , Estética Dental
7.
Int J Mol Sci ; 18(8)2017 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-28786931

RESUMEN

This study was conducted to evaluate the effect of biphasic calcium phosphate (BCP) coated with reduced graphene oxide (rGO) as bone graft materials on bone regeneration. The rGO-coated BCP bone graft material was fabricatied by mixing rGO and BCP at various concentrations. The surface charge of rGO-coated BCP was measured to be -14.43 mV, which formed a static electrostatic interaction. Cell viabilities were significantly diminished at higher concentrations of ≥100 µg/mL. The calvarial defects of 48 rats were implanted rGO-coated BCPs at a weight ratio of 2:1000 (rGO2), 4:1000 (rGO4), and 10:1000 (rGO10), repectively. BCP was used as a control group. The micro-CT and histological analysis were performed to evaluate new bone formation at 2 and 8 weeks after surgery. The results showed that the new bone volume (mm³) was significantly higher in the experimental groups than in the control group. Histological analysis showed that new bone areas (%) were significantly higher in the rGO2 and rGO10 than in the control, and significantly higher in rGO4 than in the rGO2 and rGO10. Conclusively, the rGO-coated BCP was found to be effective on osteogenesis and the concentration of the composite was an important factor.


Asunto(s)
Regeneración Ósea , Sustitutos de Huesos , Materiales Biocompatibles Revestidos , Grafito/química , Hidroxiapatitas/química , Osteogénesis , Óxidos , Animales , Sustitutos de Huesos/química , Trasplante Óseo , Línea Celular , Supervivencia Celular , Masculino , Osteoblastos/citología , Osteoblastos/metabolismo , Óxidos/química , Ratas , Microtomografía por Rayos X
8.
Int J Mol Sci ; 18(5)2017 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-28441338

RESUMEN

This study was conducted to compare 3D-printed polycaprolactone (PCL) and polycaprolactone/ß-tricalcium phosphate (PCL/ß-TCP) membranes with a conventional commercial collagen membrane in terms of their abilities to facilitate guided bone regeneration (GBR). Fabricated membranes were tested for dry and wet mechanical properties. Fibroblasts and preosteoblasts were seeded into the membranes and rates and patterns of proliferation were analyzed using a kit-8 assay and by scanning electron microscopy. Osteogenic differentiation was verified by alizarin red S and alkaline phosphatase (ALP) staining. An in vivo experiment was performed using an alveolar bone defect beagle model, in which defects in three dogs were covered with different membranes. CT and histological analyses at eight weeks after surgery revealed that 3D-printed PCL/ß-TCP membranes were more effective than 3D-printed PCL, and substantially better than conventional collagen membranes in terms of biocompatibility and bone regeneration and, thus, at facilitating GBR.


Asunto(s)
Materiales Biocompatibles/química , Regeneración Ósea/fisiología , Huesos/fisiología , Fosfatos de Calcio/química , Poliésteres/química , Impresión Tridimensional , Animales , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/uso terapéutico , Regeneración Ósea/efectos de los fármacos , Huesos/diagnóstico por imagen , Huesos/patología , Diferenciación Celular/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Colágeno/química , Perros , Fracturas Óseas/patología , Fracturas Óseas/terapia , Membranas Artificiales , Ratones , Microscopía Electrónica de Rastreo , Osteogénesis/efectos de los fármacos , Microtomografía por Rayos X
9.
J Periodontal Implant Sci ; 53(3): 233-244, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37336525

RESUMEN

PURPOSE: An implant-supported prosthesis consists of an implant fixture, an abutment, an internal screw that connects the abutment to the implant fixture, and the upper prosthesis. Numerous studies have investigated the microorganisms present on the implant surface, surrounding tissues, and the subgingival microflora associated with peri-implantitis. However, there is limited information regarding the microbiome within the internal screw space. In this study, microbial samples were collected from the supragingival surfaces of natural teeth, the peri-implant sulcus, and the implant-abutment screw hole, in order to characterize the microbiome of the internal screw space in healthy subjects. METHODS: Samples were obtained from the supragingival region of natural teeth, the peri-implant sulcus, and the implant screw hole in 20 healthy subjects. DNA was extracted, and the V3-V4 region of the 16S ribosomal RNA was sequenced for microbiome analysis. Alpha diversity, beta diversity, linear discriminant analysis effect size (LEfSe), and network analysis were employed to compare the characteristics of the microbiomes. RESULTS: We observed significant differences in beta diversity among the samples. Upon analyzing the significant taxa using LEfSe, the microbial composition of the implant-abutment screw hole's microbiome was found to be similar to that of the other sampling sites' microbiomes. Moreover, the microbiome network analysis revealed a unique network complexity in samples obtained from the implant screw hole compared to those from the other sampling sites. CONCLUSIONS: The bacterial composition of the biofilm collected from the implant-abutment screw hole exhibited significant differences compared to the supra-structure of the implant. Therefore, long-term monitoring and management of not only the peri-implant tissue but also the implant screw are necessary.

10.
J Adv Prosthodont ; 15(3): 155-170, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37441720

RESUMEN

PURPOSE: This study aims to clinically compare the fitness and trueness of zirconia crowns fabricated by different combinations of open CAD-CAM systems. MATERIALS AND METHODS: Total of 40 patients were enrolled in this study, and 9 different zirconia crowns were prepared per patient. Each crown was made through the cross-application of 3 different design software (EZIS VR, 3Shape Dental System, Exocad) with 3 different processing devices (Aegis HM, Trione Z, Motion 2). The marginal gap, absolute marginal discrepancy, internal gap(axial, line angle, occlusal) by a silicone replica technique were measured to compare the fit of the crown. The scanned inner and outer surfaces of the crowns were compared to CAD data using 3D metrology software to evaluate trueness. RESULTS: There were significant differences in the marginal gap, absolute marginal discrepancy, axial and line angle internal gap among the groups (P < .05) in the comparison of fit. There was no statistically significant difference among the groups in terms of occlusal internal gap. The trueness ranged from 36.19 to 43.78 µm but there was no statistically significant difference within the groups (P > .05). CONCLUSION: All 9 groups showed clinically acceptable level of marginal gaps ranging from 74.26 to 112.20 µm in terms of fit comparison. In the comparison of trueness, no significant difference within each group was spotted. Within the limitation of this study, open CAD-CAM systems used in this study can be assembled properly to fabricate zirconia crown.

11.
Int J Prosthodont ; 34(6): 752­755, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33651030

RESUMEN

Taking a conventional implant abutment-level impression with the gingival retraction technique can cause side effects such as gingival recession and bleeding. In order to overcome these problems, an impression technique using digital superimposition of the customized abutment is newly introduced. In this technique, digital impression data and pre-scanned abutment data are superimposed to reproduce the abutment's location and shape on computer-aided design software. The present investigation was conducted to evaluate the clinical accuracy of the newly adapted digital superimposition impression technique by assessing the fit of fabricated prostheses. The results showed clinical efficacy of this technique, satisfying both convenience and clinically acceptable marginal and internal fit.


Asunto(s)
Diseño Asistido por Computadora , Atención Odontológica , Técnica de Impresión Dental , Humanos
12.
Biomed Res Int ; 2020: 7929585, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33204715

RESUMEN

This retrospective clinical study was conducted to evaluate the clinical usefulness of a freely removable microlocking implant prosthesis (MLP) that was developed to overcome the problems with conventional implant prostheses. A total of 54 patients (male: 31, female: 23) and 100 implant prostheses were included. Patients were divided into three groups such as 6-12 months, 12-18 months, and 18-24 months according to the used period after implant prosthesis delivery, and the patients in each group were recalled for examinations of survival rate, marginal bone resorption, peri-implant soft tissue indices, and complications. The prosthetic complications were analysed by combining the recorded chart data during the periodic checks including the last call for this study. During a 2-year observation period, all the implants showed a 100% survival rate without clinical mobility and functional problems. There was no significant difference in marginal bone resorption, plaque index, and bleeding index over the observation period after implant prosthesis delivery. Probing depth of the 18-24 months group (1.5 ± 0.19 mm) was significantly lower than that of the 6-12 months group (p < 0.05). The main complication was abutment loosening (4%), followed by implant prosthesis fracture (2%) and food impaction (2%) which were recorded. Within the limits of the present study, the implant prostheses with MLP are considered to be an applicable and predictable treatment method.


Asunto(s)
Prótesis Dental de Soporte Implantado , Resorción Ósea , Diseño de Implante Dental-Pilar/efectos adversos , Implantes Dentales , Placa Dental/etiología , Retención de Prótesis Dentales , Prótesis Dental de Soporte Implantado/efectos adversos , Diseño de Equipo , Femenino , Hemorragia Gingival/etiología , Humanos , Masculino , Estudios Retrospectivos , Factores de Tiempo
13.
Materials (Basel) ; 13(20)2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-33076566

RESUMEN

The purpose of this study was to evaluate the bone regeneration efficacy of an 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC)-cross-linked collagen membrane for guided bone regeneration (GBR). A non-cross-linked collagen membrane (Control group), and an EDC-cross-linked collagen membrane (Test group) were used in this study. In vitro, mechanical, and degradation testing and cell studies were performed. In the animal study, 36 artificial bone defects were formed in the mandibles of six beagles. Implants were inserted at the time of bone grafting, and membranes were assigned randomly. Eight weeks later, animals were sacrificed, micro-computed tomography was performed, and hematoxylin-eosin stained specimens were prepared. Physical properties (tensile strength and enzymatic degradation rate) were better in the Test group than in the Control group. No inflammation or membrane collapse was observed in either group, and bone volumes (%) in defects around implants were similar in the two groups (p > 0.05). The results of new bone areas (%) analysis also showed similar values in the two groups (p > 0.05). Therefore, it can be concluded that cross-linking the collagen membranes with EDC is the method of enhancing the physical properties (tensile strength and enzymatic degradation) of the collagen membranes without risk of toxicity.

14.
Int J Prosthodont ; 32(4): 352-354, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31283813

RESUMEN

PURPOSE: To examine and compare the trueness between a computer-aided design (CAD) file and the final milled prosthesis. MATERIALS AND METHODS: For each included patient (n = 30), two lithium disilicate crowns were produced (n = 60) using two different CAD/computer-assisted manufacture (CAD/CAM) systems (all-in-one type and combination type). To compare the trueness, the scanned internal surfaces of the fabricated prostheses were compared to the design files in CAD using 3D analysis software (Geomagic Control X, 3D Systems). RESULTS: The mean ± standard deviation root mean square value for posterior teeth was 32.2 ± 9.4 in the combination type group and 43.8 ± 11.7 in the all-in-one type group, indicating higher trueness for the combination type (P < .05). CONCLUSION: This study has shown that the final milled prosthesis in combination type CAD/CAM systems had better trueness than the all-in-one system.


Asunto(s)
Adaptación Marginal Dental , Diseño de Prótesis Dental , Diseño Asistido por Computadora , Coronas , Técnica de Impresión Dental , Porcelana Dental , Humanos
15.
Materials (Basel) ; 12(11)2019 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-31174298

RESUMEN

The aim of this study was to evaluate the wear properties of opposed dental ceramic restorative CAD/CAM materials and several posterior direct restorative composite resins. Three kinds of dental ceramics CAD/CAM materials (monolithic zirconia, lithium disilicate, leucite) and four dental composite resins-that is, MI Gracefil, Gradia Direct P, Estelite Σ Quick, and Filtek Supreme Ultra-were used in this study. For each of the 12 groups (three ceramics × four composite resins), five each of a canine-shaped ceramic specimen and a cuboidal shape opposing composite resin were prepared. All of the specimens were tested in a thermomechanical loading machine (50 N, 100,000 cycles, 5/55 °C). Wear losses of ceramic specimens and composite resin specimens were evaluated using a three-dimensional profiling system and an electronic scale, respectively. Statistical analyses were performed using the Kruskal-Wallis test and Mann-Whitney U test with Bonferroni's correction. Zirconia showed significantly less volumetric loss than lithium disilicate or leucite regardless of composite resin type (p > 0.05/3 = 0.017), and that Estelite Σ Quick showed significantly more weight loss than Filtek Supreme Ultra, MI Gracefil, or Gradia Direct P regardless of ceramic type (p > 0.05/6 = 0.083). Zirconia showed less volumetric loss than lithium disilicate or leucite. Some composite resins opposing ceramics showed considerable weight loss.

16.
Biomed Res Int ; 2018: 2876135, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29682530

RESUMEN

This study was undertaken to evaluate the effect of 3D printed polycaprolactone (PCL)/ß-tricalcium phosphate (ß-TCP) scaffold containing bone demineralized and decellularized extracellular matrix (bdECM) and human recombinant bone morphogenetic protein-2 (rhBMP-2) on bone regeneration. Scaffolds were divided into PCL/ß-TCP, PCL/ß-TCP/bdECM, and PCL/ß-TCP/bdECM/BMP groups. In vitro release kinetics of rhBMP-2 were determined with respect to cell proliferation and osteogenic differentiation. These three reconstructive materials were implanted into 8 mm diameter calvarial bone defect in male Sprague-Dawley rats. Animals were sacrificed four weeks after implantation for micro-CT, histologic, and histomorphometric analyses. The findings obtained were used to calculate new bone volumes (mm3) and new bone areas (%). Excellent cell bioactivity was observed in the PCL/ß-TCP/bdECM and PCL/ß-TCP/bdECM/BMP groups, and new bone volume and area were significantly higher in the PCL/ß-TCP/bdECM/BMP group than in the other groups (p < .05). Within the limitations of this study, bdECM printed PCL/ß-TCP scaffolds can reproduce microenvironment for cells and promote adhering and proliferating the cells onto scaffolds. Furthermore, in the rat calvarial defect model, the scaffold which printed rhBMP-2 loaded bdECM stably carries rhBMP-2 and enhances bone regeneration confirming the possibility of bdECM as rhBMP-2 carrier.


Asunto(s)
Proteína Morfogenética Ósea 2/farmacología , Regeneración Ósea/efectos de los fármacos , Fosfatos de Calcio/farmacología , Matriz Extracelular/fisiología , Osteogénesis/efectos de los fármacos , Osteogénesis/fisiología , Poliésteres/farmacología , Cráneo/efectos de los fármacos , Factor de Crecimiento Transformador beta/farmacología , Células 3T3 , Animales , Materiales Biocompatibles/farmacología , Diferenciación Celular/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Humanos , Masculino , Ratones , Impresión Tridimensional , Prótesis e Implantes , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/farmacología , Porcinos , Andamios del Tejido
17.
J Adv Prosthodont ; 9(4): 244-251, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28874990

RESUMEN

PURPOSE: The purpose of this study was to determine fracture resistance and failure modes of three-unit fixed dental prostheses (FDPs) made of lithium disilicate pressed on zirconia (LZ), monolithic lithium disilicate (ML), and monolithic zirconia (MZ). MATERIALS AND METHODS: Co-Cr alloy three-unit metal FDPs model with maxillary first premolar and first molar abutments was fabricated. Three different FDPs groups, LZ, ML, and MZ, were prepared (n = 5 per group). The three-unit FDPs designs were identical for all specimens and cemented with resin cement on the prepared metal model. The region of pontic in FDPs was given 50,000 times of cyclic preloading at 2 Hz via dental chewing simulator and received a static load until fracture with universal testing machine fixed at 10°. The fracture resistance and mode of failure were recorded. Statistical analyses were performed using the Kruskal-Wallis test and Mann-Whitney U test with Bonferroni's correction (α=0.05/3=0.017). RESULTS: A significant difference in fracture resistance was found between LZ (4943.87 ± 1243.70 N) and ML (2872.61 ± 658.78 N) groups, as well as between ML and MZ (4948.02 ± 974.51 N) groups (P<.05), but no significant difference was found between LZ and MZ groups (P>.05). With regard to fracture pattern, there were three cases of veneer chipping and two interfacial fractures in LZ group, and complete fracture was observed in all the specimens of ML and MZ groups. CONCLUSION: Compared to monolithic lithium disilicate FDPs, monolithic zirconia FDPs and lithium disilicate glass ceramics pressed on zirconia-based FDPs showed superior fracture resistance while they manifested comparable fracture resistances.

18.
Biomed Res Int ; 2017: 7140870, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28497062

RESUMEN

This study was performed to make comparative analysis of the clinical findings between the two different types of the implant-assisted removable partial dentures: removable partial dentures using implant surveyed bridge as an abutment (ISBRPD) and overdenture type of removable partial denture using implant attachment (IARPD). Implant cumulative survival rate, marginal bone resorption, probing depth, peri-implant inflammation, bleeding, plaque, calculus, and complications were evaluated on 24 patients who were treated with implants in conjunction with removable partial denture and have used them for at least 1 year (ISCRPD: n = 12; IARPD: n = 12). There was no failed implant and all implants were functioning without clinical mobility. Marginal bone loss of ISCRPD (1.44 ± 0.57 mm) was significantly lower than that of IARPD (p < 0.05). There was no significant difference in probing depth, peri-implant inflammation, bleeding, and plaque between the two groups (p > 0.05), while the calculus was significantly more observed in ISCRPD group than in IARPD group (p < 0.05). The retention loss of IARPD was the most common complication. Within the limits of the present study, it was found that well-planned ISBRPD was clinically appropriate. Longitudinal and systematic clinical studies are necessary to confirm these results.


Asunto(s)
Pérdida de Hueso Alveolar/epidemiología , Dentadura Parcial Removible/efectos adversos , Hemorragia/epidemiología , Adulto , Anciano , Pérdida de Hueso Alveolar/etiología , Femenino , Hemorragia/etiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
19.
Materials (Basel) ; 10(12)2017 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-29258172

RESUMEN

In this study, a new concept of a 3D-printed scaffold was introduced for the accurate placement of an implant and the application of a recombinant human bone morphogenetic protein-2 (rhBMP-2)-loaded bone graft. This preliminary study was conducted using two adult beagles to evaluate the 3D-printed polycaprolactone (PCL)/ß-tricalcium phosphate (ß-TCP)/bone decellularized extracellular matrix (bdECM) scaffold conjugated with rhBMP-2 for the simultaneous use as an implant surgical guide stent and bone graft material that promotes new bone growth. Teeth were extracted from the mandible of the beagle model and scanned by computed tomography (CT) to fabricate a customized scaffold that would fit the bone defect. After positioning the implant guide scaffold, the implant was placed and rhBMP-2 was injected into the scaffold of the experimental group. The two beagles were sacrificed after three months. The specimen block was obtained and scanned by micro-CT. Histological analysis showed that the control and experimental groups had similar new bone volume (NBV, %) but the experimental group with BMP exhibited a significantly higher bone-to-implant contact ratio (BIC, %). Within the limitations of this preliminary study, a 3D-printed scaffold conjugated with rhBMP-2 can be used simultaneously as an implant surgical guide and a bone graft in a large bone defect site. Further large-scale studies will be needed to confirm these results.

20.
Biomed Res Int ; 2017: 7102123, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29018818

RESUMEN

The purpose of this study is to evaluate the effect of three-dimensional preformed titanium membrane (3D-PFTM) to enhance mechanical properties and ability of bone regeneration on the peri-implant bone defect. 3D-PFTMs by new mechanically compressive molding technology and manually shaped- (MS-) PFTMs by hand manipulation were applied in artificial peri-implant bone defect model for static compressive load test and cyclic fatigue load test. In 12 implants installed in the mandibular of three beagle dogs, six 3D-PFTMs, and six collagen membranes (CM) randomly were applied to 2.5 mm peri-implant buccal bone defect with particulate bone graft materials for guided bone regeneration (GBR). The 3D-PFTM group showed about 7.4 times higher mechanical stiffness and 5 times higher fatigue resistance than the MS-PFTM group. The levels of the new bone area (NBA, %), the bone-to-implant contact (BIC, %), distance from the new bone to the old bone (NB-OB, %), and distance from the osseointegration to the old bone (OI-OB, %) were significantly higher in the 3D-PFTM group than the CM group (p < .001). It was verified that the 3D-PFTM increased mechanical properties which were effective in supporting the space maintenance ability and stabilizing the particulate bone grafts, which led to highly efficient bone regeneration.


Asunto(s)
Pérdida de Hueso Alveolar/tratamiento farmacológico , Proceso Alveolar/efectos de los fármacos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Regeneración Ósea/efectos de los fármacos , Titanio/química , Titanio/farmacología , Implantes Absorbibles , Injerto de Hueso Alveolar/métodos , Pérdida de Hueso Alveolar/metabolismo , Proceso Alveolar/metabolismo , Animales , Sustitutos de Huesos/farmacología , Trasplante Óseo/métodos , Colágeno/metabolismo , Implantación Dental Endoósea/métodos , Implantes Dentales , Perros , Regeneración Tisular Guiada Periodontal/métodos , Membranas Artificiales , Oseointegración/efectos de los fármacos
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