Effect of Er,Cr:YSGG Laser Root Conditioning on the Success of Root Coverage with Subepithelial Connective Tissue Graft: A Randomized Clinical Trial with a 6-Month Follow-Up

Objectives: Finding predictable approaches for root surface biomodification is an important challenge in the treatment of gingival recession. This study sought to assess the root coverage percentage by subepithelial connective tissue graft (SCTG) following root surface conditioning with erbium, chromium: yttrium scandium gallium garnet (Er,Cr:YSGG) laser. Materials and Methods: In this split-mouth, randomized clinical trial, 30 teeth with Miller’s Class I and II gingival recession were treated with SCTG (the Langer and Langer technique) with (case group) or without (control group) root surface conditioning with Er,Cr:YSGG laser (wavelength=2780 nm, power=0.75 W, H mode, repetition rate=20 Hz). Recession depth (RD), recession width (RW), clinical attachment level (CAL), and probing depth (PD) were assessed at the baseline (one week before surgery) and at 2 and 6 months postoperatively. The amount of root coverage was quantified in the two groups. Data were analyzed using Friedman test and Wilcoxon signed-rank test. Results: No significant difference was noted between the case and control groups in any parameter (P>0.05). Significant improvement occurred in all the measured parameters in the two groups after surgery (P<0.05). The mean root coverage at the end of the study period was 87% and 80% in the case and control groups, respectively (P=0.244), and complete root coverage was achieved in 66% and 60% of the samples in the case and control groups, respectively. Conclusions: Root surface conditioning by Er,Cr:YSGG laser improved the mean root coverage and the percentage of complete root coverage. However, these changes were not statistically significant

Fatigue Fracture Strength of Implant-Supported Full Contour Zirconia and Metal Ceramic Fixed Partial Dentures

Objectives: Zirconia restorations have been suggested as a more durable and more appealing alternative to metal restorations. However, their mechanical properties may be negatively affected by fatigue due to superficial stresses or low temperature degradation. This study aimed to assess the fatigue fracture strength of three-unit implant-supported full contour zirconia and pre-sintered cobalt-chromium (Co-Cr) alloy posterior fixed partial dentures (FPDs). Materials and Methods: In this in-vitro experimental study, 28 posterior three-unit implant-supported FPDs were fabricated of full contour zirconia and pre-sintered Co-Cr alloy, and were cemented on implant abutments. To simulate the oral environment, FPDs were subjected to 10,000 thermal cycles between 5-55°C for 30 seconds, and were then transferred to a chewing simulator (100,000 cycles, 50 N, 0.5 Hz). Afterwards, fatigue fracture strength was measured using a universal testing machine. Data were analyzed by Mann-Whitney U test. Results: The mean and standard deviation of fracture strength were 2108.6±440.1 N in full contour zirconia, and 3499.9±1106.5 N in pre-sintered Co-Cr alloy. According to Mann- Whitney U test, the difference in this respect was statistically significant between the two groups (P=0.007). Conclusions: Since the fracture strength values obtained in the two groups were significantly higher than the maximum mean masticatory load in the oral environment, both materials can be used for fabrication of posterior three-unit FPDs, depending on the esthetic demands of patients

Effect of Oral Bromelain on Wound Healing, Pain, and Bleeding at Donor Site Following Free Gingival Grafting: A Clinical Trial

Objectives: Considering the optimal efficacy of bromelain for pain relief and wound healing, this study aimed to assess the effect of bromelain on wound healing, pain, and bleeding at the donor site following free gingival grafting (FGG). Materials and Methods: This randomized, controlled double-blind clinical trial was performed on 26 patients with gingival recession. The patients were randomly divided into two groups of bromelain and placebo (n=13). Treatment was started on the day of surgery and was continued for 10 days. Pain, bleeding, and epithelialization at the donor site were the variables evaluated in this study using a questionnaire. The level of pain was determined using a visual analog scale (VAS) considering the number of analgesic tablets taken within 7 days postoperatively. Bleeding was determined according to the patient’s report, and epithelization was assessed by applying 3% hydrogen peroxide (H2O2) to the donor site. The donor site epithelialization was assessed at 7 and 10 days after surgery. Results: Bromelain caused a significant reduction in pain at the donor site (2.605±0.509) compared to the placebo (4.885±0.519; P0.05). The two groups were the same regarding postoperative bleeding (P>0.05). Conclusions: The results showed that oral bromelain (500 mg/day) can be effective in the reduction of pain at the donor site after FGG and may also enhance wound healing. Oral bromelain does not increase the risk of postoperative bleeding.

Fracture Resistance of Aged Full-Coverage All-Ceramic Zirconia and Metal-Ceramic Restorations of Implant-Supported Fixed Partial Dentures

BACKGROUND: Metal-ceramics restorations were considered a preferable option for fabrication fixed partial dentures (FPDs) that have an acceptable durability, but they are not able to provide the same beauty as the entire ceramic material. Full-contour zirconia, such as Zolid, does not have problems with chipping of layered zirconia, along with translucency and staining capabilities. AIM: This study aimed to assess the fatigue fracture strength of three-unit implant-supported full-contour zirconia and metal-ceramics posterior FPDs. MATERIALS AND METHODS: In this in vitro study, 24 posterior three-unit implant-supported FPDs were fabricated of full-contour zirconia and metal-ceramics and were cemented on implant abutments. To simulate the oral environment, FPDs were subjected to 10,000 thermal cycles between 5 and 55°C for 30 s and were then transferred to a chewing simulator (100,000 cycles, 50 N, 0.5 Hz). Afterward, fatigue fracture strength was measured using a universal testing machine. Data were analyzed using an independent sample t-test. RESULTS: The obtained results showed that the mean and standard deviation of fatigue fracture strength was higher for the metal-ceramics group (2567.8 ± 689.7 N) compared to those for the full-coverage zirconia group (2108.6 ± 455.2 N). However, the difference was not statistically significant (p ˃ 0.05). CONCLUSIONS: Fracture resistance due to fatigue in the metal-ceramics group was not significantly different from full-coverage zirconia group. Full-coverage zirconia seems promising as a metal-ceramics material for the fabrication of posterior three-unit FPDs

The comparison of two professional prophylaxis systems in plaque removal and debonding of orthodontic brackets

Introduction: During orthodontic treatment, patients are expected to undergo consistent periodic prophylaxis as a result of complexities in oral hygiene. The aim of this study was to investigate, analyze, and compare the effectiveness of two professional prophylaxis systems of rubber cup polishing (RCP) and air-powder polishing (APP) in patients undergoing orthodontic treatment based on different levels of plaque and pigment on teeth and the extent of attachment of brackets after prophylaxis. Materials and Methods: A total of 50 patients were selected for this clinical trial study. A couple of months after the orthodontic treatment, the patients were placed on professional prophylaxis in terms of the plaque index. Randomized cross-arch prophylaxis (right maxilla with left mandible), RCP (left maxilla with right mandible), and APP were carried out on the patients. The main indexes in the study (number of plaque removal and debonding), the work time duration per second, and convenience of patients using visual analog scale in each of the methods were evaluated as minor factors. Data were recorded in a special checklist. Results: The mean of the plaque index and the time spent on RCP were observed to be higher than APP. The average satisfaction rate of patients with RCP was higher than APP. The debonding of the bracket and the tooth was not observed in any of the methods. Conclusion: APP is more efficient than RCP for performing professional prophylaxis of orthodontic patients

Green synthesis of silver nanoparticles and evaluation of their effects on the Porphyromonas gingivalis bacterial biofilm formation

Abstract Objective This study aimed to evaluate the impact of silver nanoparticles (AgNPs) synthesized from propolis on the formation of Porphyromonas gingivalis biofilms. Material and Methods AgNPs were synthesized from propolis, and their inhibitory effect on P. gingivalis biofilm formation was assessed. Different concentrations of AgNPs (0.1%, 0.3%, and 0.5%) were tested to determine the dose‐dependent antibacterial activity. Results The results of this study indicated that AgNPs exhibited an inhibitory effect on P. gingivalis biofilm formation. The antibacterial activity of AgNPs was dose‐dependent, with concentrations of 0.1%, 0.3%, and 0.5% showing effectiveness. Notably, the concentration of 0.5% demonstrated the most significant anti‐biofilm formation activity. Conclusion The results of this study suggest that AgNPs synthesized from propolis have potential as an effective option for enhancing periodontal treatment outcomes. The inhibitory effect of AgNPs on P. gingivalis biofilm formation highlights their potential as alternative antimicrobial agents in the management of periodontal diseases

Effect of Resin Cement Color on the Final Color of Lithium Disilicate All-Ceramic Restorations

Objectives: Obtaining an adequate ceramic thickness to mask the substructure color is not always feasible, and appropriate use of a cement may be the only solution. This study aimed to evaluate the effect of the color of Variolink II resin cement on the final color of lithium disilicate glass ceramic restorations. Materials and Methods: In this in-vitro study, 90 discs of IPS e.max Press ceramic were evaluated. The ceramic discs were cemented to composite and amalgam blocks. The effect of the cement color and substructure on the final color of ceramic was analyzed by calculating the color change (∆E) value using a spectrophotometer. Data were analyzed via three-way analysis of variance (ANOVA) and Tukey’s test. Results: The cement color had a statistically significant effect on the final color of ceramic (P≤0.001). The white, yellow, and translucent cements caused the highest color change (ΔE=4.558, 3.308, and 2.649, respectively). The effect of composite substructure and the yellow cement on the final color was less prominent compared to other combinations of cement and substructure (ΔE=2.043). The white cement over amalgam substructure showed the greatest effect on the final color (ΔE=4.890). The ΔE in HO group was less than that of other combinations (P<0.05), and the greatest ΔE was reported in MO group with the white cement (∆E=6.255). Conclusions: The final color of the restoration is influenced by the cement color. Therefore, when IPS e.max Press is used over a metal core, it is recommended to use a cement with an HO ceramic

Photobiomodulation in Periodontology and Implant Dentistry: Part II.

Objective: Finding evidence-based treatment strategies for low-level light therapy and the correct incorporation of these treatment methods in the clinical practice of periodontics. Background: Photobiomodulation has been shown to have biostimulatory, anti-inflammatory, and analgesic effects that can be beneficial in periodontal and dental implant treatment procedures. Methods: In this review, we have addressed some clinical questions regarding the potential clinical application of low-level light irradiation and its photobobiomodulatory effects in periodontology and implantology. The literature was searched for in vivo (animal or clinical) articles written in English in four electronic databases of PubMed, Scopus, Google Scholar, and Cochrane Library until April 2019. Only studies with low irradiation doses without any thermal effects used only for their photobiomodulatory purposes were included. Results: We were able to find relevant studies for all of our questions, and positive effects for the application of light therapy were reported in most of the studies. However, there is still a great deal of heterogeneity in terms of study designs and most importantly in light irradiation devices and the parameters used. Due to this issue, it was not possible to reach specific evidence-based irradiation protocols for the questions addressed in this review. Conclusions: Based on our search results, an obvious positive effect of low-level light therapy on stimulation of healing of periodontal soft and hard tissues and reduction of inflammation can be seen. Future well-designed randomized control studies with the same irradiation settings and systematic reviews evaluating the studies found on the questions mentioned are necessary to reach evidence-based recommendations

Photobiomodulation in Periodontology and Implant Dentistry: Part I.

Objective: Finding evidence-based treatment strategies for low-level light therapy (LLLT) and the correct incorporation of these treatment methods in the clinical practice of periodontics. Background: Photobiomodulation has been shown to have biostimulatory, anti-inflammatory and analgesic effects that can be beneficial in periodontal and dental implant treatment procedures. Methods: In this review we have addressed some clinical questions regarding the potential clinical application of low-level light irradiation and its photobiomodulatory effects in periodontology and implantology. The literature was searched for in vivo (animal or clinical) articles written in English in four electronic databases of PubMed, Scopus, Google scholar, and Cochrane Library until April 2019. Only studies with low irradiation doses without any thermal effects used only for their photobiomodulatory purposes were included. Results: We were able to find relevant studies for all of our questions, and positive effects for the application of light therapy were reported in most of the studies. However, there is still great deal of heterogeneity in terms of study designs and most importantly in light irradiation devices and the parameters used. Owing to this issue it was not possible to reach specific evidence-based irradiation protocols for the questions addressed in this review. Conclusions: Based on our search results, an obvious positive effect of LLLT on stimulation of healing of periodontal soft and hard tissues and reduction of inflammation can be seen. Future well-designed randomized control studies with the same irradiation settings and systematic reviews evaluating the studies found on the questions mentioned are necessary to reach evidence-based recommendations

Comparison of the Effect of Er,Cr:YSGG Laser and Halita Mouthwash on Oral Malodor in Patients With Chronic Periodontitis: A Randomized Clinical Trial: Effect of Er,Cr:YSGG laser and Halita mouthwash on oral malodor

Introduction: Periodontal disease and tongue coatings are among the major factors associated with oral malodor. The present study, comparatively evaluated the effects of the Er,Cr:YSGG laser and Halita mouthwash as adjunctive treatments to nonsurgical periodontal debridement on oral malodor reduction in chronic periodontitis patients.Methods: Sixty patients with stage II and III chronic periodontitis and bad breath. The patients were randomly divided into two groups (n=30). After conventional scaling and root planing, patients in group 1 underwent Er,Cr:YSGG laser (Waterlase; Biolase, San Clemente, CA, USA) irradiation of the internal surface of the pockets ( 1.5 W, 30 Hz, 20% A, 40% W) and the dorsum of the tongue (1 W, 30 Hz, 20%A, 40% W) immediately after SRP and on the third and seventh days. Group 2 patients were asked to use Halita mouthwash twice daily for one week. Baseline, 1 and 3-month post-treatment measurements of plaque index (PI), probing pocket depth (PPD), clinical attachment level (CAL), gingival index (GI), bleeding on probing (BOP) and organoleptic assessment of Halitosis severity were performed.Results: Significant improvement in all parameters was noted in both groups after 1 and 3 months, compared with baseline (P&lt;0.05). The two groups had significant reductions which occurred in PPD, CAL, and BOP levels and the organoleptic score in 1 and 3 months after the intervention (P&lt;0.05).Conclusion: Er,Cr:YSGG laser irradiation and Halita mouthwash as adjuncts to non-surgical periodontal therapy are both effective in the treatment of oral malodor and improvement of periodontal parameters. DOI:10.34172/jlms.2021.2