Photobiomodulation Therapy and Dental-derived Mesenchymal Stem Cells: a Review of Literature

Introduction: The role of PBMT in regulating cellular activity as well as its biostimulation effect on cell proliferation or inhibition has led a group of studies to investigate its effect on stem cells. The aim of this review study was to investigate the effect of photobiomodulation therapy (PBMT) on the function of Dental Derived Mesenchymal Stem Cells (DDMSCs). Materials and Methods: The study was done by reviewing laboratory and clinical studies conducted until 2020 according to the following keywords: Photobiomodulation therapy, Low Level Laser Therapy, Regeneration, Dental Derived Mesenchymal Stem Cells using “and” conjunction in Pub med, Medline, Springer, Elsevier, and Science direct databases. Results: The findings of 9 related articles indicated the role of PBMT in improving proliferation and viability of DDMSCs. Also, the functional improvement of stem cells in the regeneration of dental pulp can be one of the most crucial effects of PBMT. Conclusion: In general, the most important finding of this study was the positive effect of PBMT in proliferation and differentiation of Mesenchymal stem cells (MSCs). However, the insufficient clinical trials remain an obstacle in achieving definitive results in examining the relationship between PBMT and MSCs

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.

Evaluation of Different Dentin Bonding Agents Accompanied with Composite Coronal Barrier

Introduction: The purpose of this study was to evaluate the sealing ability of dentin bonding agents in root canals obturated with gutta-percha and MTA. Methods: Forty-five single rooted human premolar teeth were decoronated so that remaining root portions were 12 mm in length. The samples were divided randomly into three experimental (n=13) and two control groups (n=3). All teeth were instrumented up to #40 K-file using step-back technique. The roots were obturated with gutta-percha/AH26 and MTA for 5 and 3 mm, respectively. Excite, Clearfil SE Bond, and iBond were applied for experimental groups and then 2mm was filled with composite Filtek Z250. The roots in the controls were merely instrumented and obturated. Two coats of nail varnish were applied on the surface of the teeth in the experimental and positive groups, except 2 mm around the apical foramen and coronal surfaces. In the negative control, the surfaces were completely covered by two layers of nail varnish. After thermocycling, the roots mounted in plastic caps of tubes containing BHI medium and inoculated coronally with Enterococcus faecalis. The data were statistically analyzed using Fisher's exact and Kaplan-Meier survival Analysis. Results: There were no statistically significant differences between three experimental groups regarding the leakage rate (P=0.738). Conclusion: Within the limitations of this study, it was observed that the adhesive systems in alliance with gutta-percha and MTA obturation could not entirel

Evaluation of Diode laser (940 nm) irradiation effect on microleakage in class V composite restoration before and after adhesive application

Introduction: Nowadays, the main focus of dental studies is on adhesive dental materials; since clinical long-term success of bonded restorations depended more on marginal microleakage minimization. So, the aim of this study was Evaluation of Diode laser irradiation effect on microleakage in class V composite restoration before and after adhesive application. Materials and methods: In this in vitro-experimental study, standard class V cavity was prepared on lingual and buccal surfaces of 60 premolar teeth. For evaluation of microleakage, 60 teeth were divided randomly into four groups A, B, C, D (n=15): A) primer + adhesive (Clearfil TM SE Bond), B) primer + Diode laser + adhesive (940nm wave-length, 21J total energy, 0.7W power, 30s irradiation time) C) primer + adhesive + Diode laser D) primer + Diode laser + adhesive + Diode laser. Then, restoration was completed by Z250 composite. For data analyzing, we used SPSS 16 software. For statistical analysis, we used Non-parametric Kruskal-Wallis & Mann-Whitney tests at 0.05% significance level.  Results: According to non-parametric Kruskal-Wallis test, microleakage scores had not significant difference before and after laser irradiation on gingival margins (p=0.116). But, in occlusal margins the results were significant among the groups (p=0.015). Also according to non-parametric Mann-Whitney tests among the occlusal microleakage scores, group B and D (Diode laser irradiation after primer and Diode laser irradiation after primer and adhesive) showed significant results. Conclusion: This study findings showed that in 6th generation adhesives, Diode laser irradiation on self-etch primer before bonding have significant effect on reduction of occlusal marginal microleakage in class V cavities although there was no significant positive effect of Diode laser on gingival margins

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

Socio-demographic determinants as predictors of oral hygiene status and gingivitis in schoolchildren aged 7-12 years old: A cross-sectional study.

OBJECTIVE:Gingivitis and poor oral hygiene status are the most prevalent oral diseases among primary school students. Poor oral hygiene status, gingivitis and socio-demographic determinants have been shown to be associated with periodontal diseases. There is limited information on the gingivitis and oral hygiene status among Iranian children. In the present study, the status of gingivitis, oral hygiene status, and their association with socio-demographic determinants among schoolchildren aged 7-12 years old in Hamadan were investigated. METHODS:In this cross-sectional study, 988 primary school students aged 7-12 years old were selected. The oral hygiene status was measured through Simplified Oral Hygiene Index (OHI-S) and Community Periodontal Index (CPI) was used to evaluate gingival bleeding and calculus. CPI was measured using a standardized protocol to investigate gum bleeding and calculus. The oral hygiene was classified as good, fair or poor based on calculus and debris measurements. Age, gender, educational level, occupation and residence district of parents, dental pain experience in the last year and whether parents supervised their children while brushing were assessed by the questionnaires. The collected data were analyzed using descriptive statistics and logistic regression analysis. RESULTS:The oral hygiene status was good in 644 students (65.20%), fair in 341 (34.50%) and poor in three (0.30%). Moreover, the results of CPI depicted that 639 students (64.07%) had healthy periodontium, 320 (32.40%) had periodontal bleeding and 29 (2.9%) were with calculus. Higher percentage of the boys in the age group of 12 years old had periodontal bleeding and fewer good oral hygiene. The results of CPI and OHI-S scores depicted that more than half of the primary school students had healthy gums and periodontium (64.1%) and good oral hygiene status (65.2%). There were significant statistical associations between age and residence district with calculus measured by the CPI, also between gender, age, residence district, and mother's occupation with the gingival bleeding measured by the CPI. Furthermore, age and mother's occupation were significantly associated with OHI-S index. CONCLUSIONS:In general, the periodontal health status is poorer in students attending suburban schools compared to those in urban schools in Hamadan. Since there are significant associations between gender, school districts and mother's occupation with oral hygiene index among schoolchildren in primary schools, considering them in schools' oral health program design might be useful

Association of caries experience and dental plaque with sociodemographic characteristics in elementary school-aged children: a cross-sectional study

Abstract Background Dental caries among Iranian elementary school children aged 6–12 years continue to rise. To estimate treatment needs and guide health initiatives, current epidemiologic data are required. Such data are currently unavailable for dental health. The purpose of this study was to assess caries experience, dental plaque, and associated factors in elementary school-aged children from Iran. Methods In this cross-sectional study, 988 elementary school children aged 7–12 years were selected by multistage cluster sampling. Dental caries was studied using the WHO criteria, dental plaque was examined according to O’Leary index. Data on parental education and occupation, living district, dental pain within the past year, and tooth brushing habits under parental supervision were collected through interviews based on questionnaire. The data were analyzed with descriptive statistics and logistic and linear regression. Results The mean (SD) age of the elementary school children was 9.64 (1.73) years. The highest dmft was seen in elementary school children aged 7–8 years 6.53 (4.37) and the highest DMFT and dental plaque was in 12 year olds recorded as 1.17 (1.77) and 51.97 (25.86), respectively. The proportion of decayed teeth in 7 years old elementary school based on dmft index was 80.36%, moreover, the proportion in 12 years old elementary school was 40.17% based on the DMFT index. Age, gender, and dental pain within the past year were significantly associated with DMFT and dmft. The odds of developing dental caries (DMFT) was 1.70 times higher in girls than in boys (p < 0.001) and 1.72 times higher in the students that reported dental pain frequently than in those who did not (p = 0.005). The chance of developing dental caries (dmft) was 0.47 times lower in girls than boys (p < 0.001). Age was significantly correlated with dental plaque such that Plaque Index increased by 2.44 times per one year increase in age (p < 0.001). Conclusion Results indicated that dental caries experience and plaque formation among elementary school children in Hamadan were high and they were influenced by their sociodemographic factors. The associations found can be used as a helpful guide for planning accurate preventive programs for elementary school children in this region

3D-Printed Soft Membrane for Periodontal Guided Tissue Regeneration

Objectives: The current study aimed to perform an in vivo examination using a critical-size periodontal canine model to investigate the capability of a 3D-printed soft membrane for guided tissue regeneration (GTR). This membrane is made of a specific composition of gelatin, elastin, and sodium hyaluronate that was fine-tuned and fully characterized in vitro in our previous study. The value of this composition is its potential to be employed as a suitable replacement for collagen, which is the main component of conventional GTR membranes, to overcome the cost issue with collagen. Methods: Critical-size dehiscence defects were surgically created on the buccal surface of the roots of canine bilateral mandibular teeth. GTR treatment was performed with the 3D-printed membrane and two commercially available collagen membranes (Botiss Jason® and Smartbrane-Regedent membranes) and a group without any membrane placement was considered as the control group. The defects were submerged with tension-free closure of the gingival flaps. Histologic and histometric analyses were employed to assess the periodontal healing over an 8-week experimental period. Results: Histometric evaluations confirmed higher levels of new bone formation in the 3D-printed membrane group. Moreover, in all defects treated with the membranes, the formation of periodontal tissues, bone, periodontal ligaments, and cementum was observed after 8 weeks, while in the control group, only connective tissue was found in the defect sites. There was no clinical sign of inflammation or recession of gingiva in any of the groups. Significance: The 3D-printed gelatin/elastin/sodium hyaluronate membrane can be safe and effective for use in GTR for periodontal tissue regeneration therapies, with better or comparable results to the commercial collagen membranes