Temporary Restorative Materials Research Articles

Silver nanoparticles incorporated dental restorative resin and its antibiofilm effect

Dental restoration materials are susceptible to bacterial biofilm formation, which damages the restorations and causes oral health problems. Therefore, to overcome this, silver nanoparticles (AgNPs) are studied widely due to their antimicrobial, anti-inflammatory and healing properties. The purpose of this study was to develop a strategy for incorporating AgNPs onto the surface of bisacrylic resin (Bis) to evaluate its antibiofilm effects using Streptococcus sanguinis and Actinomyces naeslundii . AgNPs with an average size of 25 nm at two different concentrations were dispersed on the Bis surface (Bis-AgNPs) by mechanical deposition. Ag release was quantified until 7 days of incubation. Bacterial growth was assessed using a viability assay kit and observed using confocal microscopy. The biofilm biomass was quantified using arbitrary fluorescence units. Cell viability was evaluated using an MTT assay. The results showed that Bis-AgNPs significantly inhibited biofilm formation along with a significant difference in the viability of human gingival fibroblasts. The quantification confirmed a decrease in Ag release over time, and elemental mapping showed AgNP penetration up to 10 µm from the surface. Therefore, it was concluded that Bis-AgNPs presented enhanced antibiofilm properties, even at a concentration with no adverse effects. Therefore, this nanocomposite may be a promising alternative for biofilm control in temporary restorative materials.

Evaluation of the Effect of Various Beverages and Food Materials on the Color Stability of Provisional Materials: An In Vitro Study.

Aim This study aims to evaluate the color stability of four provisional materials: polymethyl methacrylate (DPI®Self-Cure), 10-ethoxylated bisphenol A dimethacrylate (Oratemp® C&B), bis-acryl composite resin (Systemp® C&B, Ivoclar Vivadent), and bis-acryl composite (Systemp® C&B, Ivoclar Vivadent) combined with light-cure composite (Fusion Flo® LC). Materials and methods A total of 40 specimens were meticulously crafted from modeling wax into discs, each precisely 2 mm thick and 20 mm in diameter. Four provisional materials were packed into molds, yielding 10 specimens for each material group. After mixing and polymerization, the specimens were trimmed and polished. Reflectance spectrophotometers were used for initial color assessments based on the CIELAB color space system. Staining solutions, including coffee, Tata Green Tea, Pepsi, and turmeric, were prepared to mimic dietary agents. Artificial saliva, replicating oral conditions, was formulated and sterilized. The specimens were then immersed in various solutions for 15 days at 37 °C. Color measurements were taken on days 2 and 15 using the same spectrophotometer, calculating color differences (ΔE) from changes in L*, a*, and b* values. Results DPISelf-Cure (polymethyl methacrylate)was found to be the most color-stable temporary restorative material, followed by Vivadent (bis-acryl composite resin), Oratemp (10-ethoxylated bisphenol A dimethacrylate), and Fusion Flo (light-cure composite). Fusion Flo exhibited the highest color change by the 15th day. Coffee and green tea demonstrated the greatest potential for causing color changes in the provisional restorative materials. Conclusion DPI Self-Cure exhibited the highest color stability among the provisional materials, with Vivadent and Oratemp following closely behind. Green tea and coffee were the most potent staining agents, while Pepsi and turmeric induced lesser color changes.

Effect of Post-Printing Conditions on the Mechanical and Optical Properties of 3D-Printed Dental Resin.

This study aimed to evaluate the flexural strength (FS), surface wear, and optical properties of 3D-printed dental resins subjected to different post-printing conditions. A total of 240 specimens (2 × 2 × 25 mm³) were 3D-printed using resin materials for permanent (VaresoSmile Crown Plus) VSC and temporary (VaresoSmile Temp) VST restorations. Specimens underwent five post-printing conditions: no post-printing cure; post-cured in a Form Cure curing unit; Visio Beta Vacuum; Ivoclar Targis; or heat-cured (150 °C) for 30 min. Each group of specimens (n = 24) was tested either directly after post-curing, after 24 h of dry storage, or following hydrothermal accelerated aging in boiling water for 16 h. The three-point bending test was used to evaluate the FS. The two-body wear test was performed on 50 disc-shaped specimens (n = 5/group). Surface gloss and translucency were measured for permanent VSC specimens (n = 5/group). SEM/EDS and statistical analyses were performed. The Form Cure device yielded the highest FS and lowest wear depth (p < 0.05). Hydrothermal aging significantly reduced FS. There were no statistical differences in FS and wear values between materials subjected to same post-printing conditions. VSC groups exhibited similar optical properties across different post-printing treatments. Post-printing treatment conditions had a significant impact on the FS and wear of the 3D-printed resin, while optical properties remained unaffected.

Coronal leakage of a new temporary restorative material: An invitro study

This invitro study aims to assess the potency of new temporatory restorative material Orafil LC with other temporary restoratives: Zinc oxide eugenol and Cavit G in preventing microleakage during the inter-appointment period of endodontic treatment.Endodontic access cavity was prepared on 60 premolar teeth and restored with 3 different temporary restorative materials in the respective groups. (n=20)The teeth were stored in methylene blue stain and were sectioned to be observed under a compound microscope at 1,2,3 and 7 days to access coronal microleakage and further investigations were under a scanning electron microscope. All the tested materials showed microleakage with maximum leakage in Zinc oxide eugenol followed by Cavit G and Orafil LC. Orafil LC showed the least microleakage.Orafil LC showed least microleakage when compared with other temporary restorative materials used in this study

Role of hermetic coronal seal on the long term success of apexification in immature permanent teeth induced by calcium hydroxide based regenerative materials- A pilot study

: Calcium hydroxide with or without iodoform is commonly used for apexification in immature permanent teeth. Before permanent restoration, temporary restorative material is used for ensuring coronal seal at the tooth orifice. An ideal coronal sealing agent prevents micro-leakage and maintains aseptic root canal environment. : This study aims at assessing the role of coronal seal on the long term success of apexification in immature permanent teeth by calcium hydroxide.: 51 children between the age group of 8-10 years having open apex in permanent upper anterior(s) secondary to trauma were divided into three groups, each receiving calcium hydroxide based material for apexification. Children were evaluated clinically and radiographically and followed up for a period of nine months. Cavit was used as temporary restoration in all three groups. Cases with loss of coronal seal, failure in apexification and clinical flare ups were identified. The data were statistically analyzed by Z-test and Chi-square test.: Presence of good coronal seal was directly related with successful and uneventful apexification. Loss of coronal seal was mostly related with increased evidence of clinical flare up and failure in or delayed apexification. Both the results were found to be statistically significant.: Temporary restorative materials providing meticulous coronal seal is as important as the permanent restoration, for the long term success of apexification.

Investigation of the Effect of Mouthwash on Bonding Temporary Crown Materials with Various Temporary Cements

Objectives: This study was conducted with the aim of investigating the effects of surface treatments and mouthwash on the bond strength of different temporary restorative materials with provisional cements. &#x0D; Methods: A total of 252 samples 10 mm in diameter and 2 mm in thickness were prepared from three different provisional restorative materials. Each temporary crown material was randomly divided into three separate groups, and surface treatments were applied. (no surface treatment, air abrasion, or hydrofluoric acid etching). Two types of temporary cements were bonded to the surface. Half of them were treated with mouthwash; the other half were kept in distilled water as a control group. &#x0D; Results: As the result of the analysis of variance; the interaction of the material used, the type of cement and the material*cement*retained medium was statistically very significant (p

Common Temporization of Access Cavity and Pulp Spacers Practiced by Endodontists in Saudi Arabia: A Cross-sectional Study

Background: Temporary restorations are necessary for preventing coronal leakage during and after treatment completion and must provide an effective barrier against salivary contamination of the root canal system. Endodontic spacers also help remove temporary restoration by avoiding the chances of unwanted intact tooth structure loss and perforation on the floor of the pulp chamber and prevent temporary restorative materials entrapment into the root canals resulting in canal blockage. However, the cotton pellet placed between the temporary and the root canal orifice can compromise the coronal seal by the reduction in thickness of temporary restoration. Objective: The primary aim of this investigation was to determine the most common temporary restoration used during and after endodontic treatment. The secondary aim is to know the percent preference for restorations with double seal and the frequency of spacer used. Methods: Four hundred fifty online questionnaires comprising 15 (four demographic questions and eleven questions related to the study objective) were sent to endodontists in Saudi Arabia via WhatsApp and Twitter. Statistical significance was set at P&lt;0.05 when assessed using a chi-square test. Results: About 370 (82.22%) participants completed the survey. Glass ionomer cement (GIC) was most used as a temporary restoration among endodontists for both the anterior (53%) and posterior teeth (49.7%; P=0.001). In double seal, Cavit was most used as the temporary restoration, which was placed below the seal exposed orally 56.2% (P=0.001). GIC was most used as coronal seal material placed over Cavit in 71.9% of the participants (P=0.001). About 56.2% of the endodontists placed cotton pellets between visits but not after obturation (P=0.001). Polytetrafluoroethylene tape instead of cotton pellet was preferred by 30.3% of the participants (P=0.001). Conclusion: Glass ionomer cement (GIC) was most used as a temporary restoration. In double seal, GIC was most used as coronal seal material placed over Cavit. A pulp spacer was found to be the most commonly used between visits but not after obturation.

Antibiofilm and antimicrobial activity of temporary filling materials on root canals: an in situ acid challenge.

The present study evaluated the antibiofilm and antimicrobial effects of temporary restorative materials on root canals after an intra-oral challenge. Seventy roots were endodontically treated and divided into 5 groups: high-viscosity glass ionomer (HV-GIC), light-activated glass ionomer (RM-GIC), zinc-oxide cement without eugenol (ZO), zinc-oxide cement with eugenol (ZOE), and unsealed roots (negative control). For 28 days, 14 participants used intra-oral devices with five roots, and drops of sucrose were applied onto them. The amount of biofilm and the bacterial counts were analyzed by Kruskal-Wallis and Dunn, and by two-way ANOVA and Tukey (α = 0.05). HV-GIC and RM-GIC better inhibit biofilm, followed by ZO and ZOE. Unsealed roots had the largest biofilm accumulation (p = 0.002) and higher bacterial penetration than restored roots (p = 0.023). A low amount of Streptococcus was found in RM-GIC and ZOE-restored roots without difference from HV-GIC (p = 0.021). The low amount of Enterococcus (p = 0.003) was found in the ZOE-restored roots, without difference from GICs.

Shear bond strength of orthodontic brackets to specimens fabricated from temporary restorative materials by 3D-printing, CAD/CAM technology, and the conventional technique after surface treatment by sandblasting and laser

This study assessed the shear bond strength (SBS) of stainless steel (SS) orthodontic brackets to specimens fabricated from polymethyl methacrylate (PMMA) temporary restorative material by 3D-printing, computer-aided design/computer-aided manufacturing (CAD/CAM) technology, and the conventional technique, after surface treatment by sandblasting and laser. In this in vitro study, 60 disc-shaped specimens with 8mm diameter and 1mm height were fabricated from PMMA temporary restorative material by 3D-printing, CAD/CAM, and the conventional technique. In each group (n=20), half of the specimens were sandblasted while the other half underwent Er,Cr:YSGG laser irradiation. Brackets were bonded to the specimens and underwent thermocycling followed by SBS testing. Data were analysed by one-way ANOVA, independent t-test, and LSD test (alpha=0.05). A significant difference existed among the three fabrication methods in SBS in both laser (P<0.001) and sandblasting (P<0.001) surface treatment groups. In laser group, the mean SBS of CAD/CAM (P=0.000) and conventional (P=0.000) groups was significantly lower than that of 3D-printing group. In sandblasting group, the SBS of CAD/CAM group was significantly lower than 3D-printing (P=0.000) and conventional (P=0.000) groups. The mean SBS of laser-treated specimens was significantly higher than sandblasted specimens in 3D-printing group (P=0.000), and significantly lower than sandblasted specimens in the conventional group (P=0.000). A significantly higher SBS was obtained by laser treatment compared with sandblasting irrespective of the fabrication method (P=0.000). The highest SBS of SS orthodontic brackets to temporary restorative material was recorded for 3D-printed specimens treated by Er,Cr:YSGG laser irradiation.

Comparative Evaluation of Antimicrobial Efficacy of Calcium Hydroxide, Chlorhexidine, and Triple Antibiotic Paste in Different Combination Forms as Intracanal Medicaments against Enterococcus faecalis in Primary Teeth: An In Vivo Randomized Clinical Trial.

To compare and evaluate the antimicrobial efficacy against Enterococcus faecalis (E. faecalis) between a mix of calcium hydroxide [Ca(OH)2] powder and normal saline, a mix of Ca(OH)2 powder and 2% chlorhexidine (CHX) gluconate solution, a mix of triple antibiotic powder (TAP) and normal saline, and mix of TAP and 2% CHX gluconate solution. A total of 60 teeth were included in the study. The first sample (S1) was collected after access opening from the widest canal of the tooth by inserting sterile absorbable paper point no 20 up to the full length of the canal for 1 minute. The second sample (S2) was collected after the chemomechanical preparation and irrigation. After that, subjects were randomly divided into four groups-group I-a mix of Ca(OH)2 and normal saline; group II-a mix of Ca(OH)2 and 2% CHX; group III-a mix of TAP and normal saline; and group IV-a mix of TAP and 2% CHX. Assigned intracanal medicaments were placed in the canals, and the teeth were temporarily sealed with a temporary restorative material. On the 7th day, canals were reopened and irrigated, and a third bacteriological sample (S3) was taken out. Later, canals were filled with suitable obturating material, followed by the placement of the permanent restoration. There was a very highly significant (p < 0.005) difference in E. faecalis count in all the groups on day 7 after placement of intracanal medicament, being highest in group IV followed by group II, group III, and group I. Triple antibiotic powder (TAP) mixed with 2% CHX gluconate solution has superior antimicrobial efficacy against E. faecalis in primary teeth. Qamar S, Jayanna R, Ahuja VR. Comparative Evaluation of Antimicrobial Efficacy of Calcium Hydroxide, Chlorhexidine, and Triple Antibiotic Paste in Different Combination Forms as Intracanal Medicaments against Enterococcus faecalis in Primary Teeth: An In Vivo Randomized Clinical Trial. Int J Clin Pediatr Dent 2023;16(3):448-452.

The Effect of Aging and Different Surface Treatments on Temporary Cement Bonding of Temporaray Crown Materials

Objective: The purpose of this research was to determine the effect of different surface treatments and aging on the bond strength of different temporary restorative materials with temporary cements. &#x0D; Methods: 252 temporary crown materials 2 mm thick with a 10 mm diameter were prepared. No surface treatment was administered to the control group. 4% hydrofluoric acid gel was administered to one of the other groups and sandblasted to the other. Two types of temporary cement were used. After a 5000-cycle thermal cycle was administered to half of the materials, cement bond strengths were measured. &#x0D; Results:It was found that the material used, the type of cement, the aging treatment, the material*aging treatment, and the material-cement interaction (p

Evaluation of the color stability of different temporary restorative materials

This study aimed to evaluate the color stability of different temporary restorative materials in contact with staining solutions, as well as to verify which one presents the highest resistance to staining. In this laboratory study, five types of temporary restorative materials were evaluated: self-curing acrylic resin, bis-acrylic resin, light-curing acrylic resin, CAD/CAM machinable, and 3D printed resin. Thirty samples of each material were produced in a circular mold measuring 10 mm diameter and 2 mm thickness. The materials were divided into subgroups (n=10) and immersed in solutions: Coffee, Coca-cola®, and distilled water (control). Color measurements were carried out at baseline, 1, 7, and 14 days using a digital spectrophotometer and the color parameters were calculated according to the CIEDE00 system. The color change data were subjected to two-way ANOVA (temporary material vs time) and post-hoc Tukey test (α = 0.05). The materials showed a color change only comparing baseline vs. one day, according to acceptability standard ΔE00 &gt; 1.8. Thus, we concluded that there was a difference in color stability already on the first day of immersion. In addition, the coffee solution showed the highest color variation when compared to the other solutions. Clinical applicability: Temporary restorations are widely used in prosthetic treatments and can remain in the mouth for a considerable period. They are responsible for aesthetic and function maintenance along the rehabilitation process. In addition, they provide data for the definitive prosthesis and should assure comfort and confidence to the patient. Thus, it is necessary that these materials are resistant and present such color stability that does not compromise the aesthetics during the treatment phase.

Microleakage Evaluation of Temporary Restorations Used in Endodontic Treatment-An Ex Vivo Study.

(1) Background: Coronal microleakage can lead to endodontic treatment failure. This study aimed to compare the sealing ability of different temporary restorative materials used during endodontic treatment. (2) Methods: Eighty sheep incisors were collected, uniformized in length, and access cavities were performed, except for in the negative control group, where the teeth were left intact. The teeth were divided into six different groups. In the positive control group, the access cavity was made and left empty. In the experimental groups, access cavities were restored with three different temporary materials (IRM®, Ketac™ Silver, and Cavit™) and with a definitive restorative material (Filtek Supreme™). The teeth were submitted to thermocycling, and two and four weeks later, they were infiltrated with 99mTcNaO4, and nuclear medicine imaging was performed. (3) Results: Filtek Supreme™ obtained the lowest infiltration values. Regarding the temporary materials, at two weeks, Ketac™ Silver presented the lowest infiltration, followed by IRM®, whereas Cavit™ presented the highest infiltration. At four weeks, Ketac™ Silver remained with the lowest values, whereas Cavit™ decreased the infiltration, comparable to IRM®. (4) Conclusion: Regarding temporary materials, Ketac™ Silver had the lowest infiltration at 2 and 4 weeks, whereas the highest infiltration was found in the Cavit™ group at two weeks and in the IRM® group at 4 weeks.

Cytotoxicity of 3D printed resin materials for temporary restorations on human periodontal ligament (PDL-hTERT) cells.

Various dental resin materials are available for the fabrication of temporary restorations using modern additive printing methods. Albeit these materials are placed for several months in intimate contact with dental hard and soft tissues, including the gingival crevice, there exists only insufficient evidence on the biocompatibility of these materials. This in vitro study aimed to delineate the biocompatibility of 3D printable materials on periodontal ligament cells (PDL-hTERTs). Samples of four dental resin materials for additive fabrication of temporary restorations using 3D printing (MFH, Nextdent; GC Temp, GC; Freeprint temp, Detax; 3Delta temp, Deltamed), one material for subtractive fabrication (Grandio disc, Voco) and one conventional temporary material (Luxatemp, DMG) were prepared with a standardized size according to the manufacturer's instructions. Human PDL-hTERTs were exposed to resin specimens or eluates of the material for 1, 2, 3, 6 and 9 days. For determination of cell viability, XTT assays were performed. In addition, the expression of the proinflammatory cytokines interleukin 6 and 8 (IL-6 and 8) was assessed in the supernatants with ELISA. Cell viability and the expression of IL-6 and 8 in presence of the resin material or their eluates was compared with untreated controls. Immunofluorescence staining for IL-6 and IL-8, as well as scanning electron microscopy of the discs after culturing, were performed. Differences between groups were analyzed with Student´s t-test for unpaired samples. Compared to untreated control samples, the exposure against the resin specimen induced strong reduction of cell viability in case of the conventional material Luxatemp (p<0.001) and the additive material 3Delta temp (p<0.001) irrespective of the observation period. On the contrary, the presence of eluates of the various materials induced only minor changes in cell viability. Considering IL-6 (day 2: p=0.001; day 6 and 9: p<0.001) and IL-8 (day 1: p=0.001; day 2, 3, 6, 9: p<0.001) their expression was strongly reduced in presence of the eluate of Luxatemp. Except for IL-6 at day 1 and 6 also the material 3Delta temp caused significant reduction of both proinflammatory mediators at any time point. The conventional material Luxatemp and the additive material 3Delta temp appear to severely affect cell viability when in direct contact with PDL-hTERTs. The other tested materials of this new category of additive materials and the subtractive material Grandio seem to induce only minor changes in direct contact with these cells. Therefore, they could serve as a viable alternative in the fabrication of temporary restorations.

Identifying relevant topics and their competency levels for dental materials science: a fuzzy Delphi study

BackgroundDental materials science is an important core course in undergraduate dental programs which integrates foundational concepts of chemical engineering and materials science into clinical dentistry. The present study aimed to identify relevant dental materials science topics for Malaysian undergraduate dental curricula and to determine their appropriate competency levels in terms of cognitive and psychomotor taxonomies.MethodsPotential dental materials science topics were drafted in alignment with the revised national competency statement. The list of topics was further amended after comparing it with those recommended topics in the literature. Fuzzy Delphi method was applied. Experts were selected based on the different inclusion criteria. They ranked the topics using a five-point Likert scale and recommended the appropriate cognitive and psychomotor levels. Next, fuzzy evaluation was performed. Consensus was deemed for a topic to be included if (a) the average expert agreement was ≥ 75%, (b) the d-construct threshold value for each topic was ≤ 0.2 and (c) the average fuzzy number was ≥ 0.5.ResultsSixty-two experts participated in the study. They accepted 33 out of 36 potential dental materials science topics. The average Likert score and fuzzy number ranged from 3.63 to 4.92 and 0.526 to 0.784, respectively. Furthermore, “Endodontic materials” was ranked as the most significant topic. Meanwhile, many topics required dental students to demonstrate a cognitive level of “Apply” and a psychomotor level of “Guided response”. Based on mean scores, “Impression materials” was rated as the most cognitively demanding topic, whilst “Temporary restorative materials” was the most demanding topic for psychomotor taxonomy.ConclusionThe present study has identified relevant dental materials science topics and their appropriate cognitive and psychomotor levels using the Fuzzy Delphi approach. The findings of the present study form the basis for future studies to develop measurable learning outcomes, design corresponding innovative pedagogy and propose assessment criteria for each topic.

Investigation of the Effect of Bleaching on Discolored Teeth After Regenerative Treatment on Fracture Resistance of Teeth

Objective: This study aimed to evaluate the effect of bleaching discolored teeth after regenerative endodontic treatment on fracture resistance. Methods: Forty human maxillary incisors were selected for the study and were divided into four study groups (n=10). Group 1 was called the positive control group, and no treatment was applied. In Group 2; root canals were enlarged to size 6 peezo reamer bur to mimic an immature tooth. The disinfection protocol was performed according to the regenerative endodontic treatment protocol of the American Association of Endodontists. 3 mm thick mineral trioxide aggregate (MTA) was placed at the cementoenamel margin and restored with a temporary restorative material. The samples in group 3 were restored with glass ionomer and composite resin. In Group 4 bleaching was applied with 35% hydrogen peroxide bleaching agent to the samples before restoration with glass ionomer and composite resin. Then each group was applied to the cervical fracture resistance test with a universal testing machine. The fracture resistance values were recorded in Newtons (N), and the obtained data were analyzed statistically. Results: While the highest fracture strength was obtained in group 1 (1092 ±9.27N), the lowest fracture resistance was observed in group 2 (493.8 ±7.60N). The difference between all groups was statistically significant (p&amp;lt;0.05). Conclusion: 35% hydrogen peroxide bleaching agent application after regenerative endodontic treatment reduces fracture resistance of the tooth.

Evaluation of Color Stability of Temporary Crown and Bridge Materials against External Staining: A Comparative In vitro Study

Abstract Background: Temporary restorations are essential part of fixed prosthodontic treatment as they function to protect the abutment tooth during the fabrication of final prosthesis. Objectives: The objective of the study was (i) to assess color stability of three temporary crown and bridge restorative materials toward external staining due to commonly consumed beverages and also at different time intervals of 1, 3, and 5 weeks and (ii) To assess the discoloration effect of different staining agents on the three temporary crown and bridge materials. Materials and Methods: Protemp4, Accutemp, and Oratemp, commercially available temporary crown and bridge restorative materials, were assessed after immersion into the staining solutions such as coffee, cold beverage (Coke), chlorhexidene mouthwash, turmeric solution, and synthetic saliva for 1, 3, and 5 weeks. The color measurement was performed using an NS 810 spectrophotometer, which is in accordance with the International Commission on Illumination. The statistical analysis used was analysis of variance test, Bonferroni test, post hoc correction, and Tukey’s test. Results: It was observed that the factors which significantly affected color stability included the constitution of provisional material, type, and exposure time of the staining solution. Oratemp manifested maximum discoloration, whereas Accutemp manifested the least discoloration on exposure to staining solutions for 5 weeks. Turmeric solution had the most remarkable color change on all types of temporary crown and bridge materials. Conclusion: Accutemp could be preferred for long-term provisional restorations, whereas Protemp4 and Oratemp can be given for a shorter time period.

Comparative physical and mechanical properties of a 3D printed temporary crown and bridge restorative material.

The objective was to compare physic-mechanical properties of different materials used for temporary restorations. Protemp 4/bisacrylic resin, Jet/acrylic resin, and Nexdent C&B/3D-printed resin samples (10mm diameter x 2mm thickness) were analyzed for surface roughness and color stability tests (baseline, after 5 thousand brushing cycles; and after artificial aging in water at 60oC for 24 hours) and Knoop microhardness. All data were checked for normality using Shapiro-Wilk test. Surface roughness and color stability were analyzed using two-way repeated measurements ANOVA, microhardness data was subjected to one-way ANOVA. All tests were followed by Tukey test and were performed with α=0.05. For roughness, material (p=.002), time points (p=.002) and interaction between both (p<.001) were significant. All groups presented similar roughness for measurements of baseline and after brushing. After artificial aging, 3D printed resin showed decreased roughness when compared with other resins, and with its baseline reading. Acrylic resin showed an increase in surface roughness (when compared with measurement after brushing cycles). Considering color stability, only the material (p=.039) and the time (p<0.001) were significant. All groups showed similar color variation before and after artificial aging. There was an increase in color alteration after artificial aging for all groups. Considering microhardness test (p<.001), the 3D printed resin showed the highest values and acrylic resin the lowest. Bysacylic resin was similar to both 3D printed and acrylic resins. The tested 3D printed resins present similar or better properties than other tested temporary materials while being integrated with the digital workflow. Key words:Disinfection methods, hydroxyl radical, environment, surfaces, dentistry.

Effect of polishing methods on the surface roughness of different temporary restorative materials

Aim: The purpose of this study was to evaluate the effects of different polishing methods on the surface roughness of temporary prosthetic restorations. Methodology: In this study, 200 specimens were obtained from Structur 2, Imident, FSM Duo CAD, and Han Temp Crown. All specimens were sanded with 400-, 800-, and 1000-grit silicon carbide. Next, the specimens were divided into five subgroups (n = 10). The specimens in first group were sanded with 1200-, 1600-, and 2000-grit silicon carbide sandpaper. The second group was polished with an aluminum oxide-containing disc. The third group was polished with a diamond-containing pad. A glaze bond was applied to the specimens in the fourth group. The fifth group was glazed with a coat of nano-filled resin. Then, the surface roughness of all specimens was measured with a profilometer. A two-way ANOVA test was performed using SPSS 20.0. Finally, the microstructures of the surfaces were examined by a scanning electron microscope at 5000× magnification. Results: Statistically significant results were obtained between the temporary materials and polishing methods in terms of surface roughness (p &lt; 0.05). For the polishing method, the highest surface roughness values were observed in the control group (0.50 ± 0.15). The lowest surface roughness values were observed in the Equia Forte GC coat group (0.25 ± 0.10). Among the temporary crown materials, the highest roughness was observed in Imicryl specimens. (0.45 ± 0.17), while the least roughness was the polymethyl-methacrylate (PMMA) specimens (0.17 ± 0.10). Conclusion: Surface polishing and finishing procedures might positively affect the surface roughness of temporary materials. Furthermore, materials made via computer-aided design and computer-aided manufacturing (CAD-CAM) demonstrate structural advantages and may be preferable. How to cite this article: How to cite this article: Kavut İ, Uğur M, Tanrıkut ÖO. Effect of polishing methods on the surface roughness of different temporary restorative materials. Int Dent Res 2022;12(3):149-57. https://doi.org/10.5577/intdentres.2022.vol12.no3.7 Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

SEM analysis of the endodontic cavity wall after removal of restorative materials used as temporary restoration.

The aim of the present in vitro study was to analyze the endodontic cavity walls for presence of remnants of conventional glass ionomer cement and flowable light cure composite used as temporary restorative materials of endodontically treated teeth. The dentine surface of the access cavity was observed with scanning electron microscopy after the final removal of the temporary restoration using high-speed turbine and diamond bur or ultrasonic device and diamond tip.