Microtensile bond strength of resin cements to 3-D printed and milled temporary restorative resins / Resistencia de unión en microtracción de cementos resinosos a resinas para provisionales impresas y fresadas

Abstract To evaluate the microtensile bond strength (µTBS) of two resin cements to 3D printed and milled CAD/CAM resins used for provisional fixed partial dentures. Blocks (5 x 5 x 5 mm) of three 3D-printed resins (Cosmos3DTemp / Yller; Resilab3D Temp / Wilcos and SmartPrint BioTemp, / MMTech) were printed (Photon, Anycubic Technology Co.). A milled material (VitaCAD-Temp, VITA) was used as control. Half the specimens were sandblasted and the rest were untreated. Two blocks were bonded with the corresponding resin cement: PanaviaV5 (Kuraray Noritake) and RelyX Ultimate (3M Oral Care). After 24 hours, the bonded blocks were sectioned into 1 x 1 mm side sticks. Half the beams were tested for µTBS and the other half was thermocycled (5000 cycles, 30s dwell-time, 5s transfer time) before µTBS testing. A four way Generalized Linear Model (material*sandblasting*cement*aging) analysis was applied. VITA exhibited the lowest µTBS, regardless of the cement, sandblasting and thermocycling. Sandblasting significantly improved the µTBS of VIT, especially after aging, but did not improve the µTBS of 3D printed resins. Sandblasting was not beneficial for 3D printed resins, although is crucial for adhesive cementation of milled temporary resins. Airborne particle abrasion affects the integrity of 3D-printed resins, without producing a benefit on the microtensile bond strength of these materials. However, sandblasting is crucial to achieve a high bond strength on milled temporary resins.

Resumen Evaluar la resistencia adhesiva en microtracción (µTBS) de dos cementos resinosos a resinas CAD/CAM impresas y fresadas indicadas para restauraciones provisionales. Bloques (5 x 5 x 5mm) de tres resinas impresas (Cosmos3DTemp / Yller; Resilab3D Temp / Wilcos and SmartPrint BioTemp, / MMTech) y una resina fresada (VitaCAD-Temp, VITA) fueron fabricados. La mitad de los especímenes fueron arenados y el resto no recibió tratamiento mecánico. Dos bloques con condiciones de tratamiento iguales fueron cementados con cemento resinoso (PanaviaV5 / Kuraray Noritake y RelyX Ultimate / 3M Oral Care). Después de 24 horas los bloques fueron seccionados en palitos de 1 mm² de área. En la mitad de los especímenes se midió la TBS inmediatamente y el resto fue termociclado (5000 ciclos, 30s remojo, 5s transferencia) antes de la prueba de TBS. Se aplica un análisis estadístico por Modelo Linear General con 4 factores (material*arenado*cemento*termociclado). La resina VITA presentó la menor µTBS, independientemente del cemento usado, el arenado y el termociclado. Sin embargo, el arenado aumentó la µTBS de VIT, especialmente después del termociclado. Por otro lado, el arenado no resultó en un aumento significativo de la µTBS de las resinas impresas. El arenado no fue beneficiosos para las resinas impresas, aunque es un paso crucial para la cementación adhesive de las resinas fresadas. El arenado afecta la integridad de las capas de las resinas impresas, sin generar un beneficio en la TBS.

Invitro Comparative Analysis of the Flexural Strength of 4 Different Commercially Available Provisional Materials Used in Fixed Partial Dentures – An Original Research

Background: Provisional Prosthesis in fixed partial dentures are subjected to Flexure under stress. Selection of appropriate material for fabrication of Provisional is of utmost importance as the Provisional prosthesis has to remain in function till definitive prosthesis is delivered. Material & Methods: Bar type specimens of four different commercially available brands for provisional restorations fabricated according to ADA specification No. 27 and immersed in artificial saliva. The specimens were fractured under 3-point loading test. Results: The flexural strength ranged between 60 to 110 Mpa. BisGMA Auto polymerizing composite resin from Dentsply Caulk shows the highest flexural strength. Conclusion: Within the limitations of this study, the flexural strengths were material specific rather than category one. The BisGMA composite based resin shows significantly higher flexural strength over other materials

Effect of Aging and Thermocycling on Flexural Strength of PEEK as a Provisional Restoration for Full Mouth Rehabilitation – An In vitro Study

Introduction: To compare the flexural strength of autopolymerizing poly methyl methacrylate resins (PMMA) resin, CAD/CAM milled PMMA and CAD/CAM milled poly ether ether ketone (PEEK) when used as provisional restorative materials for long span situations in full mouth rehabilitation after aging and thermocycling. Materials and Methods: Sixty samples (25 mm × 2 mm × 2 mm) were fabricated using autopolymerizing PMMA resin (GROUP I), CAD/CAM milled PMMA (GROUP II) and PEEK (GROUP III). The groups were subdivided into A and B and subjected to 7 days of aging and 500 cycles of thermocycling (subgroup A) and 14 days of aging and 1000 cycles of thermocycling (subgroup B), respectively, and flexural strength was evaluated using a three?point bend test. The data were analyzed with student t test and pair?wise comparison of mean values was done by ANOVA. Results: The flexural strength of PEEK subjected to 7 days of aging and 500 cycles of thermocycling (III (A) ? 6628.70 MPa) was the highest among all groups followed by PEEK subjected to 14 days of aging and 1000 cycles of thermocycling (III (B) ? 3760.50 MPa). Conclusion: The mean flexural strength of PEEK was statistically significant than the other two materials tested and hence can be recommended for use as a provisional restorative material for long span situations in full mouth rehabilitation. However, the mean flexural strength of PEEK reduced approximately by 44% when subjected to further aging

Comparison and Evaluation of Marginal Accuracy of Provisional Restoration by 3 Different Materials In vitro Study

Overview: Provisional Restoration plays a vital role in the long term Success of fixed partial restorations. A provisional restoration is a transitional restoration that provides protection, stabilization and function before Fabrication of the definitive prosthesis. A poorly adapted provisional restoration encourages plaque accumulation which can lead to periodontal conditions ranging from gingival Inflammation to periodontal support breakdown, this being especially true in cases where finish line margins are placed equigingivally or subgingivally. Aim of this in vitro study to compare the vertical marginal discrepancy of provisional restorations fabricated using light polymerized composite resin by direct technique. Materials and methods: Ivorine teeth (mandibular right and left 1st molar) were attached to the Typodont. Putty index was prepared Putty for each Ivorine tooth and prepared for a full crown restoration with a 1mm shoulder finish line and a uniform height of 6 mm of all the axial surfaces. After tooth preparation, impression was made with heavy body and light body using putty wash technique. Impression was immediately poured with die stone. Altogether sample size was 48. Provisional crowns fabricated using direct technique and cemented using Freegenol luting cement. They were divided into 3 groups, i.e. sixteen for each material. Die hardener was applied to the remaining part of the stone dies to prevent distortion of the die stone during aging process of the specimen. Each group was further divided into 8 depending on the type of aging process the specimens were subjected to: Pepsi, Tea and Arabian coffee and soaked for 54 hours. After immersion, the specimens were washed in distilled water, dried with filter paper, and subjected to marginal accuracy by Stereo microscope. Data obtained in the present study was subjected to statistical analysis using one-way ANOVA and inter group comparison was done with PostHoc Bonferroni’s correction SPSS Version 21. Results: Comparison of the buccal marginal discrepancies in the 3 materials used for temporary crowns using ANOVA showed significant changes when dipped in the 3 beverages. Significant buccal and lingual marginal discrepancy of all 3 temporary crowns was observed when immersed in tea compared to coffee and Pepsi as well as coffee with Pepsi by Post-Hoc Bonferroni’s correlation. Conclusion: Within the limitations of this study, it was concluded that, all the three temporary crowns fabricated from different materials showed significant marginal discrepancy when dipped in three different beverages

Influence of surface treatments and repair materials on the shear bond strength of CAD/CAM provisional restorations

PURPOSE: To evaluate the effect of surface treatments and repair materials on the shear bond strength and to measure the fracture toughness of CAD/CAM provisional restoration materials. MATERIALS AND METHODS: Four CAD/CAM (3D printing: Nextdent C&B and ZMD-1000B Temporary, CAD/CAM resin block: Yamahachi PMMA disk and Huge PMMA block) and four conventional (monometacrylate: Jet and Alike, dimetacrylate: Luxatemp and Protemp 4) materials were selected to fabricate disk-shaped specimens and divided into six groups according to surface treatment (n=10). CAD/CAM materials were repaired with Jet or Luxatemp, while conventional materials were repaired with their own materials. The shear bond strength was measured by using universal testing machine. Ten rectangular column-shaped specimens for each material were fabricated to measure the fracture toughness by single edge v notched beam technique. Statistical analysis was performed by one-way ANOVA. RESULTS: The highest shear bond strength of CAD/CAM materials was achieved by SiC paper + sandblasting. It was also accomplished when repairing 3D printing materials with Luxatemp, and repairing CAD/CAM resin blocks with Jet. Yamahachi PMMA disk showed the highest fracture toughness. Nextdent C&B showed the lowest fracture toughness value but no statistically significant difference from Alike and Luxatemp (P>.05). CONCLUSION: In order to successfully repair the CAD/CAM provisional restoration, mechanical surface treatment and appropriate repair material according to the CAD/CAM material type should be selected. The CAD/CAM provisional materials have proper mechanical properties for clinical use as compared to conventional materials.

Effect of delayed time, surface treatment, and repair material on shear bond strength of repaired bis-acryl composite resin

PURPOSE: The aim of this study was to evaluate the effect of delayed time, surface treatment, and repair materials on repair of bisacryl composite resin through comparison of shear bond strength and to evaluate the utility of bis-acryl composite resin repair using polymethyl methacrylate resin. MATERIALS AND METHODS: A total of 90 bis-acryl composite resin specimens were fabricated and classified into 9 test groups, each of 10 pieces according to delayed time, surface treatment and repair material. The shear bond strength of each specimen was measured using a universal testing machine immediately after fabrication and analyzed using a statistical analysis program (IBM SPSS statistics 20). After the shear bond strength measurement, the fracture surface of the specimen was observed. RESULTS: The highest shear bond strength (17.54 ± 3.14 MPa) was observed in the experimental group bonded immediately with a light-curing flowable composite resin using a bonding agent. CONCLUSION: When repairing bis-acryl composite resin, it is necessary to consider whether to remake according to the delayed time. For effective repair, it is desirable to consider appropriate materials and surface treatment methods according to the site or purpose of use.

A study of the esthetic outcomes of peri-implant soft tissue conditioning with provisional restorations and healing abutments / 口腔疾病防治

Implant restoration ; Provisional restoration ; Healing abutment ; Esthetic zone ; Esthetic outcomes@#To compare the esthetic outcomes of peri-implant soft tissue conditioning with provisional restorations and healing abutments.@*Methods @#A total of 48 patients missing a single tooth in the esthetic zone were chosen for the present study and divided into two groups. Twenty-six patients in Group A used provisional restorations to condition the peri-implant soft tissue before final restorations, while 22 patients in Group B used healing abutments to condition the soft tissue. All patients were evaluated by pink esthetic scores (PESs) at the time of the final restoration and at a 1-year follow-up. @*Results@#A total of 26 implants in Group A and 22 implants in Group B showed good peri-implant soft tissue condition. PESs at the time of the final restoration and at the 1-year follow-up in Group A were 8.18 and 8.35, respectively, and 6.73 and 8.18 in Group B, respectively. PESs at the time of final restoration and at the 1-year follow-up were not significantly different in Group A but were significantly different in Group B. The PESs of the two groups were significantly different at the final restoration but were not significantly different at the 1-year follow-up. @*Conclusions @#Provisional restoration in the esthetic zone can improve the pink esthetic effect when permanent restoration.

The immediate implant and delayed restoration in maxillary esthetic zone: A case report and literature review / 口腔疾病防治

Objective@#To investigate the effects of the related factors on the aesthetic implant restoration of anterior maxilla with a typical case report. @*Methods @#A patient, who was failed with metal-ceramic bridge half year, required an implant restoration. Before treatment, a thorough clinical and radiological examination and a SAC classification were done. The teeth were extracted in mininal truama without flap reflection, and implants were inserted with delayed restoration. A provisional restoration supported by temporary abutment was placed to guide the development of the soft tissues. Then the final impression with the custom-made transcopings was made. And a screwretention metal-resin bridge was made with CAD/CAM titanium framework.@*Results@#During follow-up the dental implants and provisional restoration provided the patient with good esthetics, pronunciation and chewing function.@*Conclusion@# Many factors may affect the success rates and asethetic effect of anterior implant restorations. Indications, pre-surgical assessments, treatments are keys to aesthetic implant restoration.

Comparative evaluation of the marginal accuracy of single crowns fabricated computer using aided design/computer aided manufacturing methods, self-curing resin and Luxatemp / 华西口腔医学杂志

<p><b>OBJECTIVE</b>This study aims to compare the marginal accuracy of single crowns fabricated using self-curing resin, Luxatemp, and computer aided design/computer aided manufacturing (CAD/CAM) methods in clinical application.</p><p><b>METHODS</b>A total of 30 working dies, which were obtained from 30 clinical teeth prepared with full crown as standard, were created and made into 30 self-curing resin, Luxatemp, and CAD/CAM single crowns. The restorations were seated on the working dies, and stereomicroscope was used to observe and measure the thickness of reference points. One-way analysis of variance, which was performed using SPSS 19.0 software package, compared the marginal gap widths of self-curing resin, Luxatemp, and CAD/CAM provisional crowns.</p><p><b>RESULTS</b>The mean marginal gap widths of the fabricated self-curing resin, Luxatemp, and CAD/CAM were (179.06±33.24), (88.83±9.56), and (43.61±7.27) μm, respectively. A significant difference was observed among the three provisional crowns (P<0.05).</p><p><b>CONCLUSIONS</b>The marginal gap width of CAD/CAM provisional crown was lower than that of the self-curing resin and Luxatemp. Thus, the CAD/CAM provisional crown offers a better remediation effect in clinical application.</p>

Chemical compatibility of interim material and bonding agent on shear bond strength

PURPOSE: The purpose of this study is finding proper bonding agents to be used when adding bis-acryl composite provisional materials. MATERIALS AND METHODS: Three bonding agents with different chemical compositions were included in this study. Forty disk shaped specimens of bis-acryl composite provisional material were prepared and divided into 4 groups according to the bonding agents. Control group didn't have bonding agent. Through the Teflon mould with 4.0 mm diameter hole with 4.0 mm thickness the same bis-acryl composite provisional material was added on the disks after the surface of each specimen was treated with designated bonding agent according to the manufacturer's instructions. Shear bond test was performed and the fractured surfaces were inspected with a microscope. One-way analysis of variance was conducted and the result was further analysed with Turkey post hoc test at the significance level of 0.05. RESULTS: The highest strength was acquired from the specimens bonded with chemical cure system and it was statistically significant (P < 0.05). This group showed 100% cohesive failures. The lowest bonding strength was recorded from the specimens used conventional light cure bonding agent, and this group's result was similar with the control group. The group used a light cure bonding agent claiming improved compatibility revealed significantly higher bond strength to the traditional light cure bonding agent group in a statistically significant way (P = 0.043). CONCLUSION: According to the bonding agent used the shear bond strength was significantly affected. Therefore the choice of proper bonding agent is important when hiring a bonding agent to add bis-acryl composite provisional materials.

Fabrication of provisional restoration on freshly prepared tooth: indirect and direct technique.

Background: Provisional restorations are fabricated to protect the prepared tooth structure during period between the preparation and the final restoration, and the techniques applied are direct, indirect and indirect direct. Various materials are used to fabricate provisional restoration, such as, preformed crown, acrylic, metal shell, composite, etc. Objectives: The study was designed to evaluate the advantages of fabrication of provisional restorations by indirect technique over direct technique. Methods: This prospective comparative study carried out in the Department of Prosthodontics, Faculty of Dentistry, Bangabandhu Sheikh Mujib Medical University, Dhaka, from January 2006 to December 2007, included 20 patients each for insertion of provisional restorations fabricated by indirect (group A) and direct (group B) technique. Outcome was evaluated on the basis of marginal adaptation, biocompatibility and aesthetic status. Results: On day 7 of provisional restoration, grade I marginal adaptation were observed in 75% and 40% of group A and group B patients, respectively, and on day 15 were 75% and 20%, respectively. Grade I biocompatibility on day 7 of group A patients were 100% and group B 30%, and on day 15 was 95% and 35%, respectively. Grade I aesthetic status on day 7 were in 100% of both group A and group B patients, and on day 15 was 95% and 85%, respectively. None of the patients was in grade III, either in marginal adaptation, biocompatibility or aesthetic status. Conclusion: Indirect provisional restoration is better and safer in relation to marginal adaptation, biocompatibility and aesthetic status.

In vitro study of fracture strength of provisional crown materials

PURPOSE: The purpose of this report was to evaluate the effect of the fabrication method and material type on the fracture strength of provisional crowns. MATERIALS AND METHODS: A master model with one crown (maxillary left second premolar) was manufactured from Cr-Co alloy. The master model was scanned, and the data set was transferred to a CAD/CAM unit (Yenamak D50, Yenadent Ltd, Istanbul, Turkey) for the Cercon Base group. For the other groups, temporary crowns were produced by direct fabrication methods (Imident, Temdent, Structur Premium, Takilon, Systemp c&b II, and Acrytemp). The specimens were subjected to water storage at 37degrees C for 24 hours, and then they were thermocycled (TC, 5000x, 5-55degrees C) (n=10). The maximum force at fracture (Fmax) was measured in a universal test machine at 1 mm/min. Data was analyzed by non-parametric statistics (alpha=.05). RESULTS: Fmax values varied between 711.09-1392.1 N. In the PMMA groups, Takilon showed the lowest values (711.09 N), and Cercon Base showed the highest values (959.59 N). In the composite groups, Structur Premium showed the highest values (1392.1 N), and Acrytemp showed the lowest values (910.05 N). The composite groups showed significantly higher values than the PMMA groups (P=.01). CONCLUSION: Composite-based materials showed significantly higher fracture strengths than PMMA-based materials. The CAD-CAM technique offers more advantages than the direct technique.

Restoring esthetics by immediately loaded implant placement.

The replacement of a single missing anterior tooth with an implant-supported crown is a demanding therapy. This report describes a treatment in which an anterior maxillary implant was immediately restored with a provisional restoration. During the provisional phase, an optimal emergence profile was created by adjusting the provisional restoration. An impression was made with an individually fabricated impression post for an accurate reproduction of the established emergence profile and, finally, a screw-retained all-ceramic crown was placed. By implementing this protocol, an optimal definitive result could be achieved, together with immediate patient satisfaction.

Pontic site development and soft tissue transfer of the esthetic area: a case report / 대한치과보철학회지

Soft tissue collapse around prepared teeth and pontic is inevitable after removal of the provisional restoration during the impression taking procedures. When inserting gingival retraction cord, soft tissue is displaced to an undesired contour. Viscosity of impression material also causes gingival displacement. Therefore, the consideration to transfer the prosthetically contoured soft tissue to master cast is required, especially in the esthetic area. In this report, the methods to maintain the soft tissue contour and transfer to the mastercast will be introduced. Harmonious contour of the soft tissue can be achieved with provisional restoration and be transferred to the master cast with two different techniques mentioned in this case report.

In vitro color stability of provisional restorative materials.

Background: Discoloration of provisional restorations can result in esthetic problems which are critically important in, for example, anterior areas and may compromise the acceptability of the restoration. Aims: The purpose of this study was to investigate the effect of tea on provisional restorative materials. Setting and Design: This study was designed to measure the degree of color change of three acrylic resin provisional materials, before and after immersion in artificial saliva and artificial saliva-tea solution for 2 and 4 weeks. Materials and Methods : Three types of acrylic provisional materials (duralay, tempron, acropars TRP), were studied. Twenty disks (20±0.1 mm by 2±0.05 mm) were fabricated from each material. Specimens were polished with acrylic bur using pumice and diamond polishing paste. Base line color was measured using a spectrophotometer. Ten disks were stored in artificial saliva and 10 were stored in a solution of artificial saliva and tea at room temperature. Color measurements were made after 2 and 4 weeks of immersion. Statistical analysis used: Differences in color changes were compared by two way ANOVA, across the six groups, followed by a Turkey-Kramer's multiple comparison test. Results: For specimens immersed in artificial saliva, the color change of methyl methacrylate materials; duralay (ΔE=4.94) and tempron (ΔE=6.54), was significantly more than butyl methacrylate material; acropars (ΔE=4.10). After immersion in an artificial saliva- tea solution, tempron exhibited less color change (ΔE=8.50) compared to duralay (ΔE=10.93) and acropars (ΔE=15.64). Conclusion: Color stability of methyl methacrylate is higher than butyl methacrylates so if provisional materials are used for extended periods of time; tempron is preferred.

In vitro study of tooth temperature change during polymerization reaction of the cold-cured resins used in provisional crown and fixed partial dentures / 대한치과보철학회지

STATEMENT OF THE PROBLEM: The cold-cured resins used in fabrication of the provisional crown and fixed partial dentures could cause pulpal damage by heat generated during exothermic polymerization reactions. PURPOSE: In this in vitro study investigates the how external conditions such as material of the matrix, thickness of the matrix and thickness of dentin affect the temperature of the tooth during polymerization reaction of the cold-cured resins. MATERIAL AND METHODS: To measure the temperature of the resin, metal die was maintained to the temperature of 37 degrees C with water bath to simulate the temperature of thetooth and thermocouple was placed in the center of the metal die. Acrylic pipe was cut in height of 1, 2, 3, 6, 10 mm and placed on the metal die and mixed resin was pored in the acrylic pipe. As the resin polymerized temperature was recorded with the thermometer. Temperature of the resin using matrix was recorded by using the individual tray relieved in different thickness 2, 5, 7, 10 mm. The material of the matrix was irreversible hydrocolloid impression material, vinyl polysilloxane impression material and vacuum-formed template. Temperature rise of the resin using different thickness of tooth section was recorded by placing tooth section on the metal die and placing resin over the tooth section. RESULTS: [Table]. CONCLUSION: 1. Temperature rise increased as the thickness of the resin increased but there was no significant differences over 3 mm thickness of the resin. 2. The lowest temperature rise was showed in irreversible hydrocolloid impression material and vinyl polysilloxane impression material, vacuum-formed template as in orders. 3. Temperature rise of the resin decreased regardless of the thickness of the matrix when vinyl polysilloxane impression material was used as the matrix. 4. When irreversible hydrocolloid impressionmaterial was used as matrix, the temperature rise of the resin decreased as the thickness of the matrix increased and there was no temperature rise when thickness of the matrix reached 10 mm. 5. The temperature rise of the resin did not decreased when Polypropylene vacuum-formed template was used as the matrix. 6. The temperature of the resin increased as the thickness of the dentin decreased.

Effect of immediate provisional restoration on the preservation of gingival contour / 대한치주과학회지

One of the central components of periodontal therapy is the improvement of esthetics. The presence and appearance of interdental papillae plays an important role of periodontal esthetics. The aim of the present study was to investigate how immediate provisional restoration preserve the shape of interdental papilla around the extraction socket and the width of bucco-lingual of gingiva. Another aim was to investigate the change in the interdental papilla and the amount of vertical bone fill of a extraction socket in relation to the interdental alveolar bone levels adjacent the alveolar socket. A total of 19 patients (11 male, 8 female, mean age of 50.57+/-8.16), who visited the Department of Periodontology, Pusan National University and had more than one anterior tooth scheduled to be extracted due to an advanced periodontal disease were included in the present study. After initial periodontal therapy, the extracted teeth were reshaped of the root and placed into the socket followed by splinting with adjacent teeth with self-curing resin. The width of bucco-lingual of gingiva and interdental papilla height were measured at baseline, 1, 3, 6, 9 and 12 month and the periapical radiographic examination were taken at baseline, 6 and 12month following the extraction. The amount of vertical bone fill in the extraction socket were calculated. At 12 months following the extraction, the changes in mesial and distal interdental papilla and the width of bucco-lingual showed -1.06+/-0.48mm, -0.84+/-0.50mm, -1.50+/-0.96mm, relatively. The positional change in the interproximal papillae was significantly associated with the interdental bone level adjacent to the extraction socket(p=0.028). The higher the interproximal bone level adjacent the extraction socket, the greater the amount of bone fill in the extraction socket(p<0.001). In conclusion, it was thought that immediate provisional restoration could minimize the loss of the width of bucco-lingual and interproximal papillae around the extraction socket. In addition, the higher the interproximal bone level adjacent the extraction socket, the greater the amount of bone fill and the smaller the reduction of papillary height around the extraction socket.