Dental Research Journal最新文献

Background: This study compared the color stability of resin-modified glass ionomer (RMGI) and Cention N bioactive restorative material following exposure to different coloring solutions.

Materials and methods: In this in vitro experimental study, 12 specimens were fabricated from Cention N and Fuji II LC RMGI and immersed in Turkish coffee, Nescafe, cola, and distilled water as control (n = 3). The color parameters of the specimens were measured after 1, 7, and 28 days of immersion in the respective solutions, and their color change (ΔE) was calculated. Data were analyzed using repeated measures ANOVA Friedman test and two-way ANOVA (alpha = 0.05).

Results: On day 1, the highest and lowest ΔE values were noted in Cention N specimens immersed in Nescafe and Cention N specimens immersed in cola, respectively. On days 7 and 28, the highest and lowest ΔE values were found in RMGI specimens immersed in Nescafe and Cention N specimens immersed in cola, respectively. The effects of the type of material and type of coloring solution and their interaction effect on ΔE of specimens at different time points were statistically significant (P < 0.05).

Conclusion: Within the limitations of this in vitro study, the results showed that Fuji II LC RMGI had lower color stability than Cention N in the long term. Nescafe caused the greatest discoloration in Fuji II LC, while Turkish coffee caused the greatest discoloration in Cention N specimens.

Background: Oral candidiasis is one of the most common fungal infections affecting the oral mucosa. It is usually managed by taking antifungal medication that might result in side effects such as toxicity and drug resistance. Therefore, consumption of herbal medicine with antifungal activity and fewer side effects has become popular. This study is a systematic review to investigate the improvement and reduction of oral candidiasis symptoms by herbal compounds compared to conventional antifungal drugs.

Materials and methods: PubMed, Scopus, Web of Science, Cochrane, and Magiran databases were searched from 1995 to 2021 based on the keywords of the question formula - oral candidiasis (P), herbal compounds (I), antifungal drugs (C), and improvement of clinical symptoms and laboratory tests (O) - to find related randomized controlled trials (RCTs) in English and Persian languages. Related articles were extracted based on inclusion and exclusion criteria and critically appraised using the modified-CONSORT checklist. The risk of bias was also assessed using the Cochrane tool.

Results: After removing duplicates and checking the title and abstract of the articles, 98 articles from 1995 to November 2021 of 715 were reviewed. 83 RCTs were excluded due to non-relevancy and 15 remained for critical appraisal, of which 5 articles were rejected. Finally, 10 articles were included in the systematic review. Based on the risk of bias assessment, one article had low risk, 6 articles had unclear risk, and 3 articles had a high risk of bias. Herbal compounds were applied in the form of gel in 3 articles, in the form of ointment and mouthwash in 1 and 6 articles, respectively. In terms of clinical improvement and laboratory findings, herbal compound mouthwashes and ointment did not have a significant difference from conventional antifungal drugs, but the articles related to compound gels reported variable effects (better, similar, and weaker). Furthermore, herbal compounds generally had more patient satisfaction than antifungal drugs.

Conclusion: It seems that herbal compounds have clinical applications in the treatment of oral candidiasis and gained more patients' satisfaction. To achieve more valid results, it is suggested to conduct more RCTs with a low risk of bias.

Background: The aim of this scoping review (ScR) according to the population, concept, and context question outline was: What factors can affect the accuracy of electronic apex locators (EALs) (concept) when determining the root canal terminus of human permanent teeth (population) in experimental studies (context)?

Materials and methods: A ScR was performed and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Reviews checklist using the following databases: PubMed/Medline, Scopus, Web of Science, and ProQuest. Studies that investigated the influence of a factor on the accuracy of the EALs were screened and included according to the inclusion criteria.

Results: A total of 1761 records were retrieved, leading to 805 studies after duplicates were removed. Applying inclusion and exclusion criteria resulted in the inclusion of 166 studies. The 20 potential influencing factors include generation/electrical working mechanism, method for application of EALs, root canal curvature, root canal length, tooth type, maxillary sinus proximity, lateral foramen, major apical foramen diameter/file size, file alloy, apical patency, preflaring, apical periodontitis/resorption, internal root resorption, perforation, irrigants, solvents, and medicaments, pulp contents, pulp vitality, orthodontic brackets, endodontic retreatment, and electromagnetic interferences were detected.

Conclusion: Although the accuracy of EALs is acceptable in most cases, the use of radiography along with EALs remains advisable to confirm the measurement in clinical scenarios.

Background: During the incremental technique of composite restorations, it is possible to be exposed to contamination of the oral environment. This study aimed to compare the effect of saliva contamination and different methods of saliva decontamination on microshear bond strength within composite surfaces.

Materials and methods: This in vitro study created 24 rectangular XT composite blocks using a silicone mold (24 mm × 10 mm × 10 mm). The blocks were divided into eight groups as follows: Group 1: Control group (without contamination); Group 2: Contaminated with saliva; Group 3: saliva + dried; Group 4: saliva + rinsed + dried; Group 5: saliva + rinsed + dried + Clearfil Self Etch Bond; Group 6: saliva + 96% ethanol alcohol; Group 7: saliva + chlorhexidine + rinsed + dried; and Group 8: saliva + rinseddried + All-Bond Universal bond. Fifteen tubes (0.7 mm × 1 mm) were attached to the prepared surfaces in each group, with five tubes allocated to each block. They were filled with composite and light-cured and stored in distilled water for 24 h. They were tested under a microshear test. The data were analyzed using one-way analysis of variance (ANOVA) and Tukey's honest significant difference (HSD) test (P < 0.05).

Results: One-way ANOVA test demonstrated significant differences among the groups concerning the mean bond strength (P < 0.001). Tukey's HSD test indicated that the bond strengths in groups 6 and 8 were similar to the control group, showing no significant difference. The lowest bond strength was observed in group 2, which measured 6 MPa.

Conclusion: Decontamination with rinsed + dried + All-Bond Universal bond and 96% ethanol alcohol were the most effective methods for improving the contaminated composites' microshear bond strength.

Background: In dentistry, esthetic restorations are vital. Adequate polishing can minimize color changes of a tooth. The aim of this study was to evaluate the effect of the Prophy-Mate neo device, which uses airflow, on surface roughness and color changes in enamel.

Materials and methods: In this in-vitro study included 30 teeth immersed in tea solution for 7 days. The specimens were divided into three groups based on the polishing procedure (airflow with calcium carbonate, airflow with sodium bicarbonate, and diamond paste). The whitening procedure was performed according to the instructions for each powder of airflow (Prophy-Mate neo, NSK, Japan) and paste. After polishing, the specimens were again immersed in a tea solution for another 7 days. Color assessment was carried out at baseline (T1) and after polishing (T2) using the CIELab* system. In addition, the morphology of the enamel surface for each specimen from each group was evaluated by profilometer at T1 and T2, and the paired t-test and Tukey's were used to compare results between groups.

Results: The variation in surface roughness (Ra) between calcium carbonate (0.381 μm) and sodium bicarbonate (0.447 μm) powders was not significant, but the performance of diamond paste was significantly better. The difference between the secondary staining after polishing was lower than the pigment absorption in the primary staining (before polishing) in the diamond paste group.

Conclusion: Overall, the study did not show any significant reduction in the amount of surface roughness and color changes in airflow compared to traditional polishing methods. The cost and services of the Prophy-Mate neo device make it challenging to introduce airflow as an alternative to conventional techniques (P<0.05).

Background: Minimizing apical debris extrusion may help reduce postoperative pain, flare-ups and enhance the patient's comfort. This study aimed to compare the apical debris extrusion weights of two rotary file systems, Denco Gold and Denco Blue, with those of hand files.

Materials and methods: In this in vitro study, 69 mandibular first molars with a curvature < 10° and two separate root canals and foramen in the mesial root were selected. The samples were randomly divided into three groups: Denco Blue rotary file, Denco Gold rotary file, and hand files. After instrumentation, the extruded apical debris was gathered in glass containers and dehumidified. The weight of the debris was measured and compared. Data analysis was conducted using SPSS 22 with one-way analysis of variance and Tukey tests.

Results: The highest mean (standard deviation) of debris extrusion weight was observed with hand files at 0.21 (0.03), followed by the Denco Gold rotary file at 0.10 (0.31), and the lowest with the Denco Blue rotary file at 0.08 (0.27). There was a significant difference (P < 0.001) between the rotary files and hand files, but no significant difference among the rotary files (P > 0.159).

Conclusion: Both Denco Blue and Denco Gold rotary files resulted in less apical debris extrusion compared to hand files, with the two rotary file systems showing similar levels of debris extrusion.

Background: Current challenges in bone grafting revolve around the limited availability of autografts and the complications associated with their use. Promising alternatives include osteoinductive substances stimulating stem cells to mature into bone-forming osteoblasts. However, existing products lack optimal characteristics of a bone graft. The study aimed to evaluate the impact of L-arginine treatment on hydroxyapatite (HA) derived from ovine bone and compare its surface and mechanical properties to that of the commercially available xenograft-Bio-Oss.

Materials and methods: The research was structured as an in vitro investigation, wherein HA was formulated from ovine bone. The sintering process involved heating it to 360°C for 3 h and adding the amino acid L-arginine. Different tests were done which included scanning electron microscopy (SEM), X-ray diffractometry, Fourier-transform infrared spectroscopy (FTIR), and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The goal was to compare these results with a commercially available bone graft called BioOss, especially regarding their physical and chemical characteristics. Data were analyzed in SPSS software using one way ANOVA test, significant level at 0.05.

Results: A bone graft made of HA and L-arginine displayed a complex and interconnected pore structure, indicating that the sintering process had a significant impact. SEM confirmed this. FTIR analysis identified peaks at 650-700 cm^-1 and 1000-1100 cm^-1, confirming the presence of HA and L-arginine. X-ray Diffraction assessments also confirmed the existence of both substances in the sintered specimens, supporting their suitability for various biomedical applications.

Conclusion: The study presents a novel approach, deproteinizing a bone graft followed by sintering at 360°C with L-arginine. Physicochemical analyses confirmed desired mechanical attributes and surface characteristics. Further investigations are needed to evaluate cellular adherence, immunological response, and osteogenesis in relevant animal models.

Background: Intraoral scanners (IOS) have been developed to address the drawbacks of traditional impression systems, such as improving patient comfort and expediting the restoration process. The objective of this study was to compare the dimensional accuracy of IOSs with traditional impression systems.

Materials and methods: In this experimental study, a maxillary reference model was utilized for the study. The mesiodistal, occlusogingival, and buccolingual distances between points were measured on the model using a digital caliper and recorded as the control group. The reference model was then scanned once using an IOS device (CEREC AC) to generate a digital model. Reference points were measured and recorded using EXOCAD V.2019 software. Sixteen alginate impressions were cast in separate trays from the reference model, and dental stone IV was poured into them. Reference points were also measured on the casts using a caliper. Finally, the measurements of IOS models, alginate templates, and reference models were compared in terms of size and dimensional differences. Data analysis was performed using the analysis of variance with independent t-tests, with a significance level of <0.05. The study utilized a maxillary reference model.

Results: The mean differences in mesiodistal dimensions of only the right second premolars (P = 0.017), buccolingual dimensions of central incisors (P = 0.037), lateral incisors (P = 0.050), and right first molar (P = 0.028) showed significant differences between IOS and alginate methods compared to the reference model. The dimensions reported in the IOS method were higher (0.71-1.26 mm) than those in the alginate method compared to the reference model.

Conclusion: Based on the results of this study and acknowledging its limitations, it can be concluded that the IOS method yielded a greater number of measurements than the reference model when evaluated on a limited number of teeth within the complete maxillary arch. However, the measurements obtained using the alginate method were more closely aligned with those of the reference model. The minimal differences observed between digital impressions and traditional measurement techniques, the IOS method may be regarded as a viable alternative to conventional methods, owing to its numerous advantages.

Background: Coronal discoloration is a common complication when using calcium silicate-based cements in esthetic zones. An ideal endodontic cement should provide favorable esthetic results alongside optimal biological and mechanical properties. This study aims to evaluate the discoloration of three calcium silicate-based cements-Cold Ceramic, Ortho MTA, and Retro MTA-in the presence of blood and normal saline.

Materials and methods: In this experimental study, 48 human anterior teeth were prepared and randomly divided into six groups (n = 8) based on the type of cement (Cold Ceramic, OrthoMTA, RetroMTA) and environment (blood or normal saline). Color analysis of tooth crowns was performed using a spectrophotometer before applying the cements and at 30 and 60 days after application. Repeated measures analysis of variance was used to evaluate the effects of blood, material type, and time on discoloration (ΔE). As the data showed a non-normal distribution, the Kruskal-Wallis test was used for intergroup comparisons, and the Wilcoxon test was applied for intragroup analyses over time (P-value < 0.05).

Results: After one month, specimens exposed to blood exhibited greater discoloration than those exposed to normal saline. All groups showed noticeable discoloration at two months, with blood exposure exacerbating the effect. Across different times and environments, OrthoMTA caused more discoloration than the other materials. However, the differences were not significant. (P-value > 0.05).

Conclusion: IIn all three groups, blood-exposed and normal saline environments caused clinically noticeable discoloration over time. These materials are, therefore, not recommended for use in esthetic zones.

Background: It is suggested to use a customized abutment confirming to the configuration of the new extraction socket. Since there are no systematic reviews regarding this issue, the aim of this systematic review was to assess the efficacy of customized healing abutments versus titanium healing abutments on peri-implant tissue healing in fresh socket implants to improve the treatment prognosis in the clinic.

Materials and methods: Electronic searches were conducted on PubMed/MEDLINE, Embase, Cochrane, and Google Scholar databases by the end of June 2022. All randomized controlled studies, prospective, retrospective, human studies of preimplant tissue healing around customized or titanium healing abutments, follow-up studies of more than 6 months, and in English were included in this study. The exclusion criteria were studies that were not clinical, with a follow-up period of <6 months, and those that assessed abutment healing.

Results: Forty-six studies were obtained following database research. Based on the eligibility criteria, five studies were finally included. Qualitative data analysis showed that two studies reported that customized abutments caused a significant decrease in a buccolingual width while two others did not report accurate results. Furthermore, one study only pointed to the significance of this change within 1 month after implant placement. Consequently, customized healing abutments may cause higher volume changes in the presence of thin bone phenotypes and facilitate the closure of large sockets. In addition, these investigations reported the same implant survival rate during the follow-up period for both methods.

Conclusion: Customized healing abutments exhibit efficacy in sealing immediate implant sockets, particularly in cases with thin bone phenotypes. These abutments induce significant volume changes, aiding in the closure of larger sockets and thereby preserving the socket volume.