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Recently , photobiomodulation has been shown to positively modulate the properties of dental pulp stem cells (DPSCs) in regenerative endodontics which is considered a promising solution to standard therapies for preserving pulp vitality and avoiding more extensive treatments such as endodontic therapy and tooth extraction. Therefore, the present study evaluated the effects of photobiomodulation and exsosomes of DPSCs for pulp regeneration in dogs . Five healthy mature mongrel dogs were divided into four groups ;group I, negative control; group II; Positive control(exposed pulp covered by A sterile piece of polytetrafluoroethylene (PTFE, Teflon tape) , group III: PBM group with 980 nm diode laser with output power 100 mw for one minute , group IV; exosomes, group V: exosomes + PBM.. Each dog represented one group. Blood samples were collected from dogs after 14dayspostoperatively. Biochemicals as total and ionized calcium, phosphorus, and alkaline phosphatase levels and the gene expression levels of matrix metallopeptidase 9, osteocalcin, transforming growth factor beta genes were measured with real-time quantitative polymerase chain reaction. Statistical analysis showed that there were significance differences between PBM, exsosomes and combination group of PBM and exsosomes compared to control group in different assessed biochemicals and genes expression’s levels. PBM combined with exsosomes enhanced the mineral content like total and ionized calcium , phosphorus level and alkaline phosphatase (ALP) as well as increased gene expression of Matrix metallopeptidase 9 (MMP 9), Transforming growth factor beta (TGF- β), and Osteocalcin OCN during pulp regeneration in dogs.

Objective: The current study assessed the effect of calcium hydroxide [Ca(OH)2] and Photobiomodulation [PBM] on pulp capping when [Ca(OH)2] is used as a dental pulp capping material on dental pulp exposures of dogs’ teeth. Methods: 48 teeth in 3 mongrel dogs were divided in random into two major study groups; group I where Ca(OH)2 was used as a pulp capping agent and group II in which both Ca(OH)2+PBM were used. The groups were equally divided according to the observation period following completion of pulp capping into Subgroup (A) 1week, Subgroup (B) 2 and subgroup (C)16weeks. The teeth were examined for histological inflammatory response as well as dentine bridge formation Results: With regards to inflammatory response at 1 week significantly less intense inflammation was observed in Ca(OH)2+PBM (group II) compared to the Ca(OH)2 (group I) for the same time period with no significant difference for between group I and group II for other time intervals. As for dentin bridge formation PBM+Ca(OH)2 groups showed statistically significant thicker dentine bridge formation at 16 weeks than Ca(OH)2 alone group for the same time period with no significant difference for between group I and group II for other time intervals.

BACKGROUND: Diabetes mellitus (DM) is a metabolic disorder resulting from hyperglycemia. Hyperglycemia contributes to oxidative stress, and the release of advanced glycation end products (AGEs) further promotes disease pathogenesis. Uncontrolled diabetes reflects great oral complications and affects human oral health. So, the present study aimed to assess the effects of photobiomodulation therapy (PBMT) and Metformin on proliferation and viability of human periodontal ligament stem cells (HPDLSCs) cultured in high glucose medium. METHODS: HPDLSCs were collected, isolated, and characterized and then divided into eight groups. Addition of extra glucose to diabetic groups 24 hours before cell irradiations. Metformin was added to half of the diabetic groups. Cells were irradiated with 808 nm diode laser 24, 48 hours. Cell viability was analyzed with MTT assay 24 hours post-irradiation to detect cell viability in each group. Real-time (PCR) was used to evaluate gene expression of Nrf2, Keap1, PIK3, and HO-1 and the effect of PBMT on Keap1/Nrf2/Ho-1 Pathway. ELISA reader was used to evaluating cell viability through (ROS, TNF-α, IL-10) protein levels after cell irradiation. RESULTS: Photobiomodulation at 1, 2, and 3 J/cm2 combined with metformin significantly promoted diabetic cell lines of HPDLSCs viability (in MTT assay and ELISA reader of ROS, TNF-α, IL-10 results) and gene expression of Nrf2, Keap1, PIK3, and HO-1 levels (p< 0.05). CONCLUSION: photobiomodulation with 3 J/cm(2) combined with metformin enhanced proliferation and viability of diabetic cell lines of HPDLSCs and thus could improve differentiation and function of diabetic cell lines of HPDLSCs with minimum side effects.

(1)BackgroundHuman periodontal ligament stem cells (HPDLSCs) are a unique population of mesenchymal stem cells (MSCs). Recently, the positive effects of photobiomodulation on the regulation of MSCs proliferation and osteogenic differentiation have gained significant attention. This study aimed to assess the effects of photobiomodulation and vitamin D (as an anabolic factor) on HPDLSCs for bone regeneration.(2)MethodsHPDLSCs were collected, isolated, and characterized and then divided into six groups: groups I and II, control and (10−7 Mol) vitamin D, respectively; group III, irradiation at 1 J/cm2 of 808-nm diode laser; group IV, irradiation at 1 J/cm2 and culture with vitamin D; group V, irradiation at 2 J/cm2, and group VI, irradiation at 2 J/cm2 and culture with vitamin D. Cell viability assay was measured through MTT assay and cell growth curve. Alkaline phosphatase (ALP) enzyme activity and mRNA levels of RUNX2, collagen 1 (Col-1), ALP, and osteonectin were also assessed.(3)ResultsPhotobiomodulation at 1 and 2 J/cm2 combined with vitamin D significantly promoted HPDLSC proliferation (in MTT assay and cell growth curve results) and osteogenic differentiation (through the gene expression of RUNX2, Col-1, ALP, and osteonectin levels (p < 0.05).(4)ConclusionLaser irradiation at 2 J/cm2 combined with vitamin D3 enhanced osteoblast differentiation and proliferation of cultured HPDLSCs and thus could further substitute bone grafting.

Introduction: The present study aimed to test the efficiency of photoinduced photoacoustic streaming using 2940 nm Er: YAG laser and 980 nm diode laser agitation on smear layer removal, sealer penetration and push-out bond strength. Methods: Sixty single canaled human permanent teeth were collected for this study. Specimens were grouped into three experimental groups (20 teeth in each group), depending on the activation protocol used for final irrigation: Group I (needle agitation), group II (980nm diode laser agitation) and group III (photon induced photoacoustic streaming (PIPS) using 2940 nm Er: YAG laser. The quantity of irrigant was standardized in all groups to 4 ml. The irrigant was activated for 40 seconds in different groups under continuous flow. Two teeth from each group were used to check the smear layer removal, and then the remaining teeth in each group were randomly divided into three equal experimental subgroups according to methods of evaluation used: subgroup A: Sealing ability evaluated by dye penetration method; subgroup B: SEM for sealer penetration; and subgroup C: Push-out bond strength assessed by the universal test machine. Results: As regards smear layer removal, results showed that the PIPS group had opened dentinal tubules, followed by the diode laser group, while the least cleaning effect was found in the Side-vented needle group. As for Sealing ability and dye penetration, a statistically significant difference was found between all of the three groups, with the Er:YAG laser (PIPS) having the best sealing ability and sealer penetration. Push-out bond strength results showed no statistically significant difference between diode and Er:YAG groups, with a significant difference between each of them and the Side-vented needle group. Conclusion: Using the diode or Er:YAG laser (PIPS) for irrigant activation led to better irrigant penetration and smear layer removal which subsequently led to obvious sealer penetration, better sealing, and strength properties of endodontic treated teeth.

Purpose: The purpose of this study was to access post-operative clinical as well as radioghraphic success of Diode Laser / Mineral Trioxide Aggregate (MTA) and Diode Laser /Biodentine (BD) pulpotomy procedures in comparison to conventional technique using Formocresol /Zinc Oxide Eugenol (FC/ZOE) pulpotomy for human primary molars. Materials and Methods: A total of 90 lower primary molars that had deep carious lesion and need pulpotomy treatment from 66 healthy and cooperative patients, aged 4-6 years old were chosen for this study. After removal of the coronal tissue and depending on the type of radicular pulp medicament, the teeth were divided randomly and equally into three groups; Group A (FC/ZOE), Group B (Diode Laser/MTA) and Group C (Diode laser/BD). Treatments in all groups were completed with Glass Ionommer restoration then stainless steel crowns. Results: The cumulative clinical and radiographic success rates after 12 months follow up were 90.3%, 96.3% and 100% for the FC/ZOE, Diode Laser/MTA and Diode Laser/BD pulpotomy groups respectively. Conclusion: Laser assessed pulpotomy in combination with MTA or Biodentine had a more advanced clinical and radiographic success rate correlated to FC/ZOE pulpotomy technique in primary molar. Statistically, no significance difference was found between the three study groups in the overall clinical and radiographic success rate.

Effect of Surface Treatments on the Color Change and Shear Bond Strength of Porcelain Laminate Veneer Aim of the study: the purpose of this Invitro study to evaluate the effect of surface treatments on the color change and shear bond strength of lithium disilicate glass ceramic veneers. Materials & Methods: Twenty square samples with dimensions (8x8x2) and another twenty samples with smaller dimensions (4x4x2) were cut from five IPS e-max CAD blocks of shade A3. The discs were divided into two groups: 1) Half of the small and large blocks were subjected to hydrofluoric acid (HF); 2) the other half was subjected to Co2 laser irradiation. The conditioned samples were subdivided according to the bonding agent: A) Silane application for 60 seconds; B) Single bond universal light cured for 10 seconds. Each small sample was cemented on the top of a large sample using Rely-x veneer cement with translucent shade. The color change was measured using spectrophotometer. The shear bond strength was tested using a universal testing machine. Results: HF resulted in higher bond shear bond strength and ΔE than Co2 laser. Single bond universal resulted in higher shear bond strength values than silane. Conclusion: HF followed by either single bond universal or silane could be the best surface treatment for e-max CAD ceramic. However, Co2 laser could be a promising alternative surface treatment.

Objective: To assess the efficacy of agitation of chlorohexidine (CHX) and Silver nanoparticles “AgNps” with 810nm diode laser or sonic endoactivator compared to side –vented needle on infected root canals with Enterococcus “E” Faecalis biofilms. Material and Methods: Sixty-five extracted human premolars with single oval canals were instrumented by protaper system up to F3. Biofilms of E. faecalis were generated based on a previously established protocol. Two teeth were used to check the biofilm formation, then the remaining Teeth were randomly divided into three equal experimental groups according to agitation techniques used: group 1 (810 nm diode laser with 1 watt), group 2 (sonic endoactivator) and group 3 (Side vented needle). Each group was further divided into three equal subgroups according to the irrigant solution into; subgroup A: chlorohexidine, subgroup B: silver nanoparticles and subgroup C: distilled water: Confocal laser scanning microscopy “CLSM” was used to assess bacterial viability. Data were analyzed by appropriate statistical analyses with P = 0.05. Results: Regarding the activation method, all groups had a significantly high percentage of dead bacteria (P < 0.05). However, Laser was significantly the highest and Endoactivator the least (P < = 0.001). Diode laser agitation of AgNps irrigant showed the highest reduction percentage of bacteria (78.1%) with a significant difference with both CHX and water irrigation, Conclusion: Under the condition of the present study; results reinforced that laser activation is a useful adjunct, 810 nm diode laser agitation of AgNps or chlorhexidine was more effective in disinfection of oval root canals than endoactivator and side vented needle techniques.KeywordsDentinal infection; Silver-nanoparticles; chlorohexidine; agitation; Diode Laser; Sonic endoactivator.

Introduction: The regeneration of dental pulp tissue using human dental pulp stem cells (HDPSCs) has attracted increasing attention in recent years. Recent studies have suggested that several factors such as photobiomodulation (PBM) and vitamin D affect the proliferation and differentiation of HDPSCs. Therefore, the present study evaluated the effects of PBM and vitamin D on odontogenic differentiation of HDPSCs for dentin -like tissue formation. Methods: HDPSCs were collected, isolated, and characterized and then divided into six groups: group I, control; group II, vitamin D (10-7 Mol); group III, irradiation at 1 J/cm2 of 810 nm diode laser; group IV, irradiation at 1 J/cm2 and culture with vitamin D; group V, irradiation at 2 J/cm2 , and group VI, irradiation at 2 J/cm2 and culture with vitamin D, cell viability assay was measured through MTT. Alkaline phosphatase (ALP) enzyme activity and mRNA levels of vascular endothelial growth factor (VEGF), bone morphogenic protein-2 (BMP-2), and dentin sialophosphoprotein (DSPP) were also assessed. Results: PBM at 1 and 2 J/cm2 combined with vitamin D significantly promoted HDPSCs proliferation through MTT assay and odontogenic differentiation through gene expression of VEGF, BMP-2, and DSPP levels (P

Objective: The purpose of this study was to assess the quality of single cone and gutta core obturation in curved root canals of the mandibular molars after needle and diode laser activation of both ethylenediaminetetraacidic acid (EDTA) and sodium hypochlorite (NaOCl) irrigation using cone beam computed tomography (CBCT) and stereomicroscope. Methods: A total of twenty –four extracted human mandibular molars with root canal curvature more than 20 degrees and type IV anatomic configuration in the mesial roots were selected for this study. Canals in mesial roots were prepared with ProTaper next instruments up to x3 and equally divided into two experimental groups (n=12) according to final one minute activation for each of 5 ml 2.5% NaOCl and 5 ml 15% EDTA using; side-vented needle (group1) or 980 nm diode laser (group2). After preparation, the mesial canals were randomly obturated with either single-cone gutta-percha (sub group A) or gutta core Obturator (subgroup B). Obturated canals were scanned with cone beam computed tomography; images were used to assess the quality of obturation at different canals levels. The roots were subsequently sectioned at 2, 4, 6, 8 and 12 mm levels from the apex for analyses of the percentage of gutta percha filled area (PGFA) and percentage of sealer filled area (PSFA) using stereomicroscope to examine the root sections. The areas of gutta percha and sealer for each segment of the root were measured using Image J software. Kruskal-Wallis test was used to analyze data. Results: Both cone beam and digital stereomicroscopic data indicated that canals obturated with gutta core after irrigant activation had the highest PGFA. The Gutta core and diode laser acti- vation group produced significantly higher PGFA and lower PSFA at different root canal levels 4,6 and 8 mm levels of the root canal (P < .05) than all other groups at the same levels (P < .05). Single cone and EDTA has the lowest PGFA and highest PSFA (P < .05). Conclusions: The results reinforced that 980-nm Diode activated irrigation improved the qual- ity of obturation of the mesial root canals in mandibular molars by using gutta core or single cone. Variation in root canal obturation technique and irrigation activation influenced the percentage of gutta percha filled area and percentage of sealer filled area.

Objective: This study evaluated clinically and radiographically, the healing in chronic apical lesions using low level laser therapy (LLLT). Methods: Twenty female patients between the ages of 20 and 30 years with chronic apical lesions in anterior maxillary teeth diagnosed on the basis of their clinical signs and symptoms and radiographic findings were included in the study. The patients were randomly divided into two main groups according to treatment plan: group I; received conventional endodontic treatment only, group II; received conventional endodontic treatment and then LLLT was used. The low level laser was applied for 120 seconds in the session for three sessions in week for four weeks and the selected parameters were (200 mw, 810 nm, CW). The healing was evaluated clinically, radiographically. Clinically to record pain, swelling, or any other adverse event that occur after treatment for one week. Radiographically to evaluate bone density and area of periapical lesions using cone beam computed tomography (CBCT) and image fusion. Images were obtained immediate after obturation and after the three follow up periods (1, 3 and 12 month) . Results: clinical signs and symptoms decreased in the lased group faster than conventional group. Pain reduction in the laser group was more effective than the conventional group without significant difference. Bone density analysis showed that Laser had significantly higher bone density after 1 ,3 and 12 month evaluation periods compared to control group (P