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1.
Statement of problem
Dental laboratories use different computer-aided design and computer-aided manufacturing (CAD-CAM) systems to fabricate fixed prostheses; however, limited evidence is available concerning which system provides the best marginal discrepancy.Purpose
The purpose of this in vitro study was to evaluate the marginal fit of 5 different monolithic zirconia restorations milled with different CAD-CAM systems.Material and methods
Thirty monolithic zirconia crowns were fabricated on a custom-designed stainless steel die and were divided into 5 groups according to the type of monolithic zirconia crown and the CAD-CAM system used: group TZ, milled with an MCXL milling machine; group CZ, translucent zirconia milled with a motion milling machine; group ZZ, zirconia milled with a dental milling unit; group PZ, translucent zirconia milled with a zirconia milling unit; and group BZ, solid zirconia milled using an S1 VHF milling machine. The marginal fit was measured with a binocular microscope at an original magnification of ×100. The results were tabulated and statistically analyzed with 1-way ANOVA and post hoc surface range test, and pairwise multiple comparisons were made using Bonferroni correction (α=.05).Results
The type of CAD-CAM used affected the marginal fit of the monolithic restoration. The mean (±SD) highest marginal discrepancy was recorded in group TZI at 39.3 ±2.3 μm, while the least mean marginal discrepancy was recorded in group IZ (22.8 ±8.9 μm). The Bonferroni post hoc test showed that group TZI was significantly different from all other groups tested (P<.05).Conclusions
Within the limitation of this in vitro study, all tested CAD-CAM systems produced monolithic zirconia restorations with clinically acceptable marginal discrepancies; however, the CAD-CAM system with the 5-axis milling unit produced the best marginal fit. 相似文献2.
Fernanda de Cássia Papaiz Gonçalves Marina Amaral Alexandre Luiz Souto Borges Luiz Fernando Martins Gonçalves Tarcisio José de Arruda Paes-Junior 《The Journal of prosthetic dentistry》2018,119(4):606-610
Statement of problem
Complete-arch implant-supported prostheses without a framework have a high risk of failure: a straightforward and inexpensive reinforcement material, such as nylon mesh, could improve their longevity.Purpose
The purpose of this in vitro study was to evaluate a nylon-silica mesh compound on the fracture strength of acrylic resin and the fracture load of complete-arch implant-supported prostheses.Material and methods
Twenty-four complete mandibular arch implant-supported prostheses were divided into 2 groups according to cantilever length (molar and premolar) and subdivided into another 2 subgroups according to the presence or absence of reinforcing mesh. The specimens were submitted to a maximum load-to-fracture test in a universal testing machine, with a 100-N load cell, a 2 mm/min crosshead speed, and a spherical metal tip diameter of 4 mm at different points (molar and premolar). These were submitted to 1-way analysis of variance for repeated measurement and the post hoc Tukey multiple comparison test (α=.05).Results
The mean maximum load ±standard deviation for the molar group was 393.4 ±95.0 N with reinforcement and 305.4 ±76.3 N without reinforcement (P=.02); and for the premolar group was 1083.3 ±283.7 N with reinforcement and 605.3 ±90.5 N without reinforcement (P=.001).Conclusions
Reinforcement with nylon mesh increased the mean maximum load of implant-supported complete-arch prostheses at both cantilever lengths. The cantilever to the premolar (5 mm) presented the highest maximum load values to fracture. 相似文献3.
4.
Wonsup Lee Young-Jun Lim Myung-Joo Kim Ho-Beom Kwon 《The Journal of prosthetic dentistry》2017,117(4):532-538
Statement of problem
A simplified mounting technique that adopts an average condylar guidance has been advocated. Despite this, the experimental explanation of how average settings differ from individual condylar guidance remains unclear.Purpose
The purpose of this in vitro study was to examine potential occlusal error by using average condylar guidance settings during nonworking side movement of the articulator.Material and methods
Three-dimensional positions of the nonworking side maxillary first molar at various condylar and incisal settings were traced using a laser displacement sensor attached to the motorized stages with biaxial freedom of movement. To examine clinically relevant occlusal consequences of condylar guidance setting errors, the vertical occlusal error was defined as the vertical-axis positional difference between the average setting trace and the other condylar guidance setting trace. In addition, the respective contribution of the condylar and incisal guidance to the position of the maxillary first molar area was analyzed by multiple regression analysis using the resultant coordinate data.Results
Alteration from individual to average settings led to a positional difference in the maxillary first molar nonworking side movement. When the individual setting was lower than average, vertical occlusal error occurred, which might cause occlusal interference. The vertical occlusal error ranged from -2964 to 1711 μm. In addition, the occlusal effect of incisal guidance was measured as a partial regression coefficient of 0.882, which exceeded the effect of condylar guidance, 0.431.Conclusions
Potential occlusal error as a result of adopting an average condylar guidance setting was observed. The occlusal effect of incisal guidance doubled the effect of condylar guidance. 相似文献5.
《Dental materials》2022,38(1):e10-e18
ObjectivesTo evaluate the force absorption capacity of implant supported restorations utilizing different CAD-CAM materials for the fabrication of crowns and customized abutments.Methods80 titanium inserts were scanned to design customized abutments and crowns. The specimens were divided into four groups (n = 20/material): (Z): zirconia, (P): PEEK, (V): VITA Enamic, and (E): IPS e.max. Each group was subdivided into two subgroups according to customized abutment material: (Z) zirconia, and (P) for PEEK. For the assessment of force absorption, all specimens were loaded in a universal testing machine, applied loads curves were collected from the machine’s software, and resulting loads curves were collected from forcemeter below the assembly. The slopes of all curves were analyzed using Two-way multivariate analysis of variance with pairwise comparisons using Tukey Post Hoc test (p < 0.05).ResultsThe curve progression of the applied and resulting forces varied among the investigated materials for each specimen. For zirconia abutments, ZZ showed the highest slope values of the applied and resulting force curves, followed by EZ, VZ, and PZ demonstrating statistically significant differences (P < .001). As for PEEK abutments, ZP and EP showed the least slope values, followed by PP then VP demonstrating statistically significant differences (P < .001). For Zirconia and e.max crowns, using PEEK abutments significantly increased slope loss. As for PEEK and Vita Enamic crowns changing abutment material did not significantly affect slope loss.SignificanceCombining rigid crown materials with less rigid abutments might enhance their force absorption capacity. However, with less rigid crown materials a stiff substructure might be mandatory to preserve their force absorption behavior. 相似文献
6.
Priscilla Kia Suan Sia Radi Masri Carl F. Driscoll Elaine Romberg 《The Journal of prosthetic dentistry》2017,117(2):283-288
Statement of problem
Currently, no guidelines exist to help in the selection of Locator abutments for implants at different heights.Purpose
The purpose of this in vitro study was to evaluate the effect of the differential heights of pairs of Locator abutments on the retention of overdentures after 6 months of simulated function.Material and methods
In vitro testing was performed with 4 sets of average-sized edentulous mandible analogs with 2 implants placed in the canine positions. There were 10 specimens in each of the 4 groups, with a total sample size of 40. Four groups of 2 implant-retained overdentures were fabricated, with Locator attachments at different vertical levels with differences of 0, 2, 4, and 6 mm. The overdentures were subjected to simulated function for a period corresponding to 6 months of clinical service and then tested with a universal testing machine for changes in peak load-to-dislodgement. The data were analyzed using 1-way ANOVA followed by the Tukey honest significant differences test (α=.05).Results
Varying the heights of Locator abutments had a statistically significant effect on the retentive values of the pink Locator attachments after 6 months of simulated function (F=7.342, P=.001). The peak load-to-dislodgement ranged from 32.3 N (95% confidence interval [CI]: 26.0 to 38.6) for group 0 mm to 53.6 N (95% CI: 46.3 to 60.8) for group 6 mm. When the difference in Locator abutment heights was 2 and 4 mm, the peak load was 37.1 N (95% CI: 32.3 to 42.0) and 41.9 N (95% CI: 31.2 to 52.7). Statistical analysis revealed that the retention of group 0 mm and group 2 mm was significantly lower than group 6 mm. The retention of group 4 mm was not significantly different from groups 0 mm, 2 mm, or 6 mm.Conclusions
Although significant differences were found among the groups, these differences were small and may not be clinically detectable. 相似文献7.
Background
Addition of glass ionomer cement (GIC) has been suggested to improve the setting time and handling characteristics of mineral trioxide aggregate (MTA). This study evaluated the effect of adding GIC to MTA in terms of calcium release, an issue that has not been previously studied.Materials and methods
The study comprised four groups with five samples each: a control group of MTA alone and experimental groups I (1MTA:1GIC), II (2MTA:1GIC), and III (1MTA:2GIC) based on the mixture of MTA and GIC powders in the respective proportions by volume. Calcium release from the samples was measured by atomic absorption spectrophotometry at 15 min, 6 h, 24 h, and 1 week after setting. The level of statistical significance was set at p < 0.05.Results
Groups I (1MTA:1GIC) and III (1MTA:2GIC) released significantly less calcium than the control group at all time periods, except at 15 min for group I. Group II (2MTA:1GIC) showed no significant difference in calcium release compared to the control at any time period. Group II exhibited greater calcium release than group I or III at all time periods, with significant differences between groups I and II at 1 week and between groups I and III at 24 h and 1 week. There were no statistical differences in calcium release between groups I and III.Conclusions
Adding GIC to improve the setting time and handling properties of the MTA powder can be detrimental to the calcium-releasing ability of the resultant mixture, depending on the proportion of GIC added. Adding MTA and GIC at a proportion of 2:1 by volume did not impact calcium release from the mixture. These findings should be verified through further clinical studies. 相似文献8.
K. Siva sankar K. Pranitha A.J. Sai Sankar B. Sujatha V. Sai krishna K. Kiran kumar 《Pediatric Dental Journal》2018,28(3):160-164
Background
Remineralizing agents are found to be effective in the remineralization of early enamel caries and the remineralized enamel crystallites are more resistant to decalcification and also have the same orientation as the original enamel crystallites. Although child formula fluoridated dentifrices are used safely by young children their remineralizing capability remains questionable.Aim
To evaluate the remineralizing potential of three commercially available pediatric dentifrices on artificial carious lesions in primary teeth.Materials and methods
A total of fifty sound human primary teeth were coated with nail varnish leaving a window of 2 mm × 4 mm on buccal surface and were subjected to demineralization for a period of 96 h and then sectioned. Out of the hundred sections obtained, ninety sections are equally divided into three groups with thirty in each group: Group I (Colgate Spider man), Group II (Kids bunny), Group III (Kidodent) subjected to remineralization respectively for 10 days using pH cycling model. The sections were then evaluated under the stereomicroscope for the remineralization values using MICAP image analyser software.Results
Statistical analysis was done by using ANOVA test which showed that all the three dentifrices showed remineralization with artificial carious lesions. Among the three test groups, Group I showed higher remineralization potential compared with the other two pediatric dentifrices which was statistically significant (p < 0.05).Conclusion
All the three dentifrices demonstrated remineralization of carious lesions by virtue of decrease in lesion depth. 相似文献9.
Verónica Andrade Alejandra Martínez Ninón Rojas Helia Bello-Toledo Paulo Flores Gabriela Sánchez-Sanhueza Alfonso Catalán 《The Journal of prosthetic dentistry》2018,119(5):862.e1-862.e7
Statement of problem
Interim restorations are occasionally left in the mouth for extended periods and are susceptible to bacterial infiltration. Thus, dental interim cements with antibacterial properties are required.Purpose
The purpose of this in vitro study was to determine in vitro antibacterial activity against Streptococcus mutans and to compare the diametrical tensile strength (DTSs) of dental interim cement modified with zinc oxide nanoparticles (ZnO-NPs) with that of cement modified with terpenes.Material and methods
Antibacterial properties of ZnO-NPs, terpenes, and dental interim cement modified with ZnO-NPs and cement modified with terpenes against S mutans were tested according to minimum inhibitory concentration (MIC) and direct contact inhibition (DCI). Tensile strength levels were evaluated using DTS. Results were analyzed using the Kolmogorov-Smirnov, ANOVA, and Tamhane tests (α=.05).Results
The MICs of ZnO-NPs and terpenes against S mutans were 61.94 μg/g and 0.25% v/v, respectively. The DCI assay under the cylinders of cement (area of contact with the agar surface) revealed significant bacterial growth inhibition on Temp-Bond NE specimens with ZnO-NPs at MIC of 495.2 μg/g (8× MIC) and with terpenes at MIC 0.999% v/v (4× MIC) (P<.05). The Temp-Bond NE cement cylinder (control group) showed the lowest DTS (1.05 ±0.27 MPa) of all other test groups. In the Zn-NPs group, the greatest increase occurred in the NP8 (8× MIC; 495.2 μg/g) group with a value of 1.50 ±0.23 MPa, a significant increase in DTS compared with the control and terpene groups (P<.05). In the terpene group, the highest increase corresponded to group T2 (2× MIC; 0.4995% v/v) with a value of 1.29 ±0.18 MPa.Conclusions
The addition of terpenes and ZnO-NPs to interim cement showed antibacterial activity when in contact with S. mutans ATCC 25175. Both terpenes and ZnO-NPs antimicrobial agents increased diametral tensile strength. 相似文献10.
Objective
The purpose of the present in vitro study is to compare and evaluate the shear bond strength of porcelain and composite using different bonding agents.Materials and methods
Sixty-three porcelain pellets were prepared and were divided into 9 groups. Three surface treatment and two bonding agents were evaluated. The surface treatment were: 1) sandblasting; 2) etching with 35% phosphoric acid; and 3) etching with 8% hydrofluoric acid. Applying bonding agents Scotch bond adhesive and clearfil liner bond 2V and combination of these treatments. Composite resin was condensed and light cured for 60 seconds on the porcelain specimens which were stored in distilled water at 37°C for 24 hours before mechanical testing.Results
The bond strength were significantly different according to ANOVA F-test (F = 6.28, p < 0.01) and Duncan’s Multiple Range Test. Eight percent hydrofluoric acid showed higher bond strength when compared to 35% phosphoric acid etching and sandblasting by 50 micron aluminum oxide. Highest bond strength was observed with hydrofluoric acid + clearfil.Conclusion
Etching with 8% hydrofluoric acid + clearfil liner bond showed higher bond strength when compared to hydrofluoric acid alone. This is indicative that effect of silane and etching can be use to improve mechanico chemical bonding. Among bonding agents used clearfil liner showed higher bond strength when compared to scotch bond adhesive. 相似文献11.
Min Chen Kaiyu Fu Feng Qiao Xu Zhang Yi Fan Lijun Wang Peng Li Zhou Wu Ligeng Wu 《Journal of the American Dental Association (1939)》2017,148(10):737-742
Background
In this study, the authors investigated whether extension of a tooth crack into the root can be predicted by the appearance of the crack in the crown in vitro.Methods
The authors obtained 22 cracked teeth from 22 patients who underwent extraction, and they scanned the teeth using microcomputed tomography. The length and width of the crack on the occlusal surface (LOS and WOS, respectively) and the length of the crack on the proximal surface (LCPS) were measured on 3-dimensional reconstruction images. The pulp chamber roof was penetrated and removed. A crack line visible under the microscope only on the access cavity wall rather than extending to the bottom of the pulp chamber was termed a “nonroot crack.” A crack seen at the bottom of the pulp chamber or root wall was termed a “root crack.” The authors analyzed the data using Pearson correlation coefficients and receiver operating characteristic curves.Results
There was a significant correlation between the LOS and LCPS (correlation coefficient, 0.782; P < .001) and between the WOS and LCPS (correlation coefficient, 0.651; P < .05). The LCPS increased by 1.195 millimeters for every 1-mm increase in the LOS. The area under the receiver operating characteristic curve was 0.839 (95% confidence interval, 0.659 to 1.000) for LOS and 0.760 (95% confidence interval, 0.557 to 0.964) for WOS.Conclusions
The extent of a crown crack may indicate how far the crack extends to the root. Both the LOS and WOS may be valuable for assessing whether a crack involves the root, although the LOS seems to be more useful.Practical Implications
The dimensions of a crack in a crown provide a helpful approach for predicting the depth of the crack and its likely prognosis. 相似文献12.
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14.
Thomas C. Maveli Montry Suprono Mathew T. Kattadiyil Khaled Bahjri 《The Journal of prosthetic dentistry》2018,119(1):146-151
Statement of problem
In the evaluation and fabrication of dental prostheses, maxillary occlusal plane orientation in the sagittal and coronal planes may affect functional and esthetic outcomes. The accuracy of a recently developed electronic application in transferring this orientation to a semiadjustable articulator has not been evaluated.Purpose
The purpose of this in vitro study was to evaluate the coronal and sagittal orientation of the occlusal plane on maxillary casts mounted with an electronic application facebow system onto a corresponding semiadjustable arcon articulator.Material and methods
A maxillary typodont was placed into a phantom head (control) oriented with the Frankfort horizontal plane parallel to the horizon. A digital protractor was used to measure the angle between the occlusal plane of the maxillary arch of the phantom head and the Frankfort horizontal plane along the sagittal and coronal planes. The commercial system (test group) was used to make 15 facebow records of the maxillary typodont within the phantom head. The system records were used to mount diagnostic casts of the maxillary typodont onto a semiadjustable arcon articulator. The same measurements were made on the mounted diagnostic casts and were compared with the control. Statistical differences between the occlusal plane of the control and the occlusal plane of the mounted maxillary casts were determined using the 1-sample t test (α=.05).Results
The coronal orientation of the occlusal plane was significantly different (P<.001) between test group and control. No significant differences (P>.05) were found in the sagittal orientation of the occlusal plane.Conclusions
Within the limitations of this study, variations in the coronal plane orientation were observed with the system. Variations in this plane may lead to adverse evaluation and clinical outcomes. 相似文献15.
Statement of problem
No data are available on the ability of an impression coping to resist the manual placement of an abutment replica (implant analog) during prosthodontic laboratory procedures after a direct (pick-up) impression.Purpose
The purpose of this in vitro study was to evaluate the torque resistance of impression copings after a direct impression, that is, the amount of rotational torque sufficient to induce irreversible displacement of impression copings in the impression material bulk once the impression has been made.Material and methods
A reference model with 5 abutment replicas was constructed. Five impression copings were screwed onto the abutment replicas, and standardized impressions were made. A controlled twisting force was applied to each impression coping. A torque tester recorded the torque variation. Three elastomeric impression materials were tested. ANOVA and the Tukey test (α=.05) were performed using an average of 30 measurements per impression material, with and without adhesive.Results
ANOVA and the Tukey test results showed that the adhesive, cohesive, and mechanical bonds between the impression coping and the impression material depended greatly on the type of material and that the average rupture threshold of these bonds was statistically significantly different in pairwise comparisons (P<.05). The curve analysis showed that when the impression materials are used with adhesives, the deformation of the interface is irreversible beyond 5 Ncm of torque.Conclusions
The polyether impression material is the direct impression material that showed the highest breakdown threshold for adhesive bonding when used without an adhesive. The use of an adhesive on impression copings leads to irreversible deformation of the interface at torque stresses well below the adhesive bond threshold of the same materials used without an adhesive. 相似文献16.
Fitzgerald I Bradley GT Bosio JA Hefti AF Berzins DW 《European journal of orthodontics》2012,34(2):257-261
The purpose of this study was to compare the shear bond strengths (SBSs) of orthodontic brackets bonded with self-etching primer (SEP) using different enamel surface preparations. A two-by-two factorial study design was used. Sixty human premolars were harvested, cleaned, and randomly assigned to four groups (n = 15 per group). Teeth were bathed in saliva for 48 hours to form a pellicle. Treatments were assigned as follows: group 1 was pumiced for 10 seconds and pre-etched for 5 seconds with 37 per cent phosphoric acid before bonding with SEP (Transbond Plus). Group 2 was pumiced for 10 seconds before bonding. Group 3 was pre-etched for 5 seconds before bonding. Group 4 had no mechanical or chemical preparation before bonding. All teeth were stored in distilled water for 24 hours at 37°C before debonding. The SBS values and adhesive remnant index (ARI) score were recorded. The SBS values (± 1 SD) for groups 1-4 were 22.9 ± 6.6, 16.1 ± 7.3, 36.2 ± 8.2, and 13.1 ± 10.1 MPa, respectively. Two-way analysis of variance and subsequent contrasts showed statistically significant differences among treatment groups. ARI scores indicated the majority of adhesive remained on the bracket for all four groups. Pre-etching the bonding surface for 5 seconds with 37 per cent phosphoric acid, instead of pumicing, when using SEPs to bond orthodontic brackets, resulted in greater SBSs. 相似文献
17.
Antigoni Stylianou John O. Burgess Perng-Ru Liu Daniel A. Givan Nathaniel C. Lawson 《The Journal of prosthetic dentistry》2017,117(1):116-123
Statement of problem
The clinical challenge of adhering cement to intracanal dentin is transmitting light to the most apical parts of root canals to allow more efficient polymerization of the cement.Purpose
The purpose of this in vitro study was to compare the cement-polymerizing ability, microstructure, and radiopacity of a new fiber optic post (iLumi fiber optic Post) with a clinically successful fiber post (DT Light Post).Material and methods
Polymerizing ability was compared using a modified depth-of-polymerization protocol. A split aluminum mold with a 12-mm cylindrical hole (diameter=4.7 mm) was filled with light-polymerized resin cement (Variolink Esthetic LC). Each fiber post (n=12) was positioned and light-polymerized on the coronal end for 60 seconds with a light-emitting diode polymerization light. Unpolymerized resin was dissolved with an organic solvent, and the weight and length of the polymerized resin cement were measured. Scanning electron microscopy was used to examine vertical and horizontal cross-sections. The radiopacity values of both the posts and 5 additional reference posts were evaluated using an aluminum step wedge.Results
The weight and length of the polymerized resin cement were significantly greater (P<.05) with the fiber optic post, which scanning electron microscopy showed to have a higher density of parallel fibers. The iLumi post demonstrated greater radiopacity among the tested fiber posts and a titanium alloy post.Conclusions
The iLumi fiber optic posts have a unique structural fiber composition and excellent radiopacity and light-transmitting ability that produce more complete polymerization of the resin cement than the DT Light posts. 相似文献18.
Do different implant surfaces exposed in the oral cavity of humans show different biofilm compositions and activities? 总被引：7，自引：0，他引：7
Groessner-Schreiber B Hannig M Dück A Griepentrog M Wenderoth DF 《European journal of oral sciences》2004,112(6):516-522
Osseointegrated dental implants play an important role in restorative dentistry. However, plaque accumulation may cause inflammatory reactions around the implants, sometimes leading to implant failure. In this in vivo study the influence of two physical hard coatings on bacterial adhesion was examined in comparison with a pure titanium surface. Thin glass sheets coated with titanium nitride (TiN), zirconium nitride (ZrN) or pure titanium were mounted on removable intraoral splints in two adults. After 60 h of intraoral exposure, the biofilms were analyzed to determine the number of bacteria, the types of bacteria [by applying single-strand conformation polymorphism (SSCP analysis) of 16S rRNA genes], and whether or not the bacteria were active (by SSCP analysis of 16S rRNA). The results showed that bacterial cell counts were higher on the pure titanium-coated glass sheets than on the glass sheets coated with TiN or ZrN. The lowest number of bacterial cells was present on theZrN-coated glass. However, the metabolic activity (RNA fingerprints) of bacteria on TiN- and ZrN-coated glass sheets seemed to be lower than the activity of bacteria on the titanium-coated surfaces, whereas SSCP fingerprints based on 16S rDNA revealed that the major 16S bands are common to all of the fingerprints, independently of the surface coating. 相似文献
19.
Liliane da Rocha Bonatto Marcelo Coelho Goiato Emily Vivianne Freitas da Silva Sandra Helena Penha Oliveira Marcela Filié Haddad Antônio Hernandes Chaves Neto Victor Gustavo Balera Brito Daniela Micheline dos Santos 《The Journal of prosthetic dentistry》2017,117(6):799-805
Statement of problem
Implant-retained maxillofacial prostheses should be biocompatible, regardless of the primers and adhesives used to bond the acrylic resin and facial silicone. The authors are unaware of any study evaluating the influence of these primers and adhesives on the biocompatibility of maxillofacial prostheses.Purpose
The purpose of this in vitro study was to evaluate the cytotoxic effect of primers and an adhesive used to bond acrylic resin and facial silicone during the fabrication of implant-retained maxillofacial prostheses.Material and methods
Twenty-eight circular specimens made of resin and silicone were fabricated, either bonded or nonbonded with primer and adhesive. The specimens were divided into 7 groups: resin; silicone; resin+silastic medical adhesive type A+silicone; resin+DC 1205 primer silicone; resin+Sofreliner primer+silicone; resin+DC 1205 primer+silastic medical adhesive type A+silicone; and resin+Sofreliner primer+silastic medical adhesive type A+silicone. Eluates of the materials tested were prepared by setting 4 specimens of each experimental group in Falcon tubes with medium and incubating at 37°C for 24 hours. The eluate cytotoxicity was evaluated by an assay of survival/proliferation ((3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide [MTT] test) in cultures of human keratinocytes. The levels of IL1, IL6, TNFα, and the chemokine MIP-1α were evaluated by enzyme-linked immunosorbent assay. The mRNA expressions for MMP-9, TGF-β, and collagen type IV were analyzed by the real time polymerase chain reaction. Data were submitted to analysis of variance with Bonferroni post hoc tests (α=.05).Results
An increased cell proliferation was observed for the RAS group, with statistically significant differences (P<.001) compared with the unstimulated group. The RDCpS group showed the highest IL6 concentration values (P<.001). No significant statistical difference was found in the relative quantification of mRNA for collagen type IV, MMP9, or TGFβ between the groups (P>.05).Conclusions
The RAS group showed the highest cell proliferation percentage, while the RDCpS group exhibited the highest IL6 concentration values. No detectable levels of IL1β, TNF α, or CCL3/MIP1α were observed. The tested materials showed no toxic effects on the HaCaT cell line. 相似文献20.
Mohammad Zandi Arash Dehghan Najmeh Zandipoor Payam Amini Shideh Doulati 《Journal of cranio-maxillo-facial surgery》2018,46(3):466-472