Latifa Mohamed

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 and and the effect of PBMT on 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 , and levels (p< 0.05).

CONCLUSION: photobiomodulation with 3 J/cm 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.

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. HDPSCs were collected, isolated, and characterized and then divided into six groups: group I, control; group II, vitamin D (10 Mol); group III, irradiation at 1 J/cm of 810 nm diode laser; group IV, irradiation at 1 J/cm and culture with vitamin D; group V, irradiation at 2 J/cm, and group VI, irradiation at 2 J/cm 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. PBM at 1 and 2 J/cm combined with vitamin D significantly promoted HDPSCs proliferation through MTT assay and odontogenic differentiation through gene expression of VEGF, BMP-2, and DSPP levels ( < 0.0001). PBM at 2 J/cm combined with vitamin D enhanced the HDPSCs proliferation and odontogenic differentiation and thus could be a novel strategy for dentin regeneration in dentistry.

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.

Vital pulp therapy preserves the health of injured dental pulp tissues through improving cells viability and formation of reparative dentine. This study conducted to assess the odontogenic effects of Biodentine (BD) and 650nm laser Photobiomodulation (PBM) in dentine regeneration from human dental pulp stem cells (hDPSCs). Seventy-two hDPSCs well-plates were divided into following: Group1: control. Group2: treated by BD. Group3: treated by 650nm PBM with 1J/cm2. Group4: treated by both 650nm PBM with 1J/cm2and BD. Group5: treated by 650nm PBM with 2J/cm2. Group6: treated by both 650nm PBM with 2J/cm2and BD. Cell viability was measured by MTT assay for 4days. While odontogenic differentiation of hDPSCs was assessed by alkaline-phosphatase-activity (ALP), Alizarin red staining (ARS), western blot and Reverse-transcriptase-PCR (RT-PCR) for dentine-sialophosphoprotein (DSPP) and Runt-related-transcription-factor2 (RUNX2) at day 21. The results showed statistically significant increase in viability of all study groups against control (p-value <0.0001) at 96hours. Also showed significant differences in ALP activity between groups (p-value <0.0001) and in expression of DSPP and RUNX2 (P<0.001) compared to control. The combination of both BD and PBM 2J/cm2 showed the highest number of calcified nodules. Overall BD and PBM increase the hDPSCs odontogenic differentiation and the combination of both treatments showed better effect.

BACKGROUND: (1)Human 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.

METHODS: (2)HPDLSCs were collected, isolated, and characterized and then divided into six groups: groups I and II, control and (10 Mol) vitamin D, respectively; group III, irradiation at 1 J/cm of 808-nm diode laser; group IV, irradiation at 1 J/cm and culture with vitamin D; group V, irradiation at 2 J/cm, and group VI, irradiation at 2 J/cm 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.

RESULTS: (3)Photobiomodulation at 1 and 2 J/cm 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).

CONCLUSION: (4)Laser irradiation at 2 J/cm combined with vitamin D3 enhanced osteoblast differentiation and proliferation of cultured HPDLSCs and thus could further substitute bone grafting.

Objective: This study compared efficacy of agitation of ethylendiamintetraacetic acid “EDTA” and sodium hypochlorite “NaOCl” with 980-nm Diode laser, Endoactivator and side-vented needle on cleanliness of oval-shaped root canals. Furthermore surface temperature during lasing was evaluated.
Methods: Thirty six extracted canines with oval canals were instrumented by ProTaper Next up to X5 and equally divided into three experimental groups (n=10) and three control groups (n=2) according to final 60-second agitation (12 sec x5) for each of 5 ml 2.5% NaOCl and 5 ml 15% EDTA using; Diode laser, Endoactivator or side-vented needle. Thermocouples were utilized to measure surface temperature in laser group. SEM was used to evaluate canal walls for smear layer and debris removal. Image analysis was utilized to look at changes in dentinal tubules. Cohen Kappa, Kruskal-Wallis, and Mann-Whitney U tests were used to analyze data.
Results: Scoring and image analysis showed that all groups had overall similar capacity to remove smear layer, P>0.05. Overall debridement of instrumented and un-instrumented surfaces revealed that Laser and needle, respectively, performed significantly better than Endoactivator, P<=0.05. All groups had the least significant smear removal in the most apical region, P<=0.001. Laser effectively reduced debris along canal length. Variable regional debris removal was evident for Endoactivator and needle. Maximum mean surface temperature rise was 2.4±0.6°C.
Conclusions: The results reinforced that laser activation is a useful irrigating adjunct. 980-nm Diode Laser agitation of EDTA and NaOCl was more effective in cleaning oval root canals than Endoactivator and side-vented needle techniques.

The purpose of the present study was to evaluate the efficacy of chlorhexidine, ultrasonic and
photodynamic therapy against E.faecalis in dental root canals, Sixty teeth were used in this study.
The crowns were decapitated and the root canals were biomechanically prepared using step-back
technique, root canals were inoculated with E.faecalis (ATCC 292 12) for 2 days. Teeth were
divided into three main experimental groups, twenty teeth each, according to the method of intra
canal treatment. Group (I), chlorhexidine, Group (II), ultrasonic + chlorexidine, while Group
(III), photodynarnic therapy (Asptim), in group I: Teeth in that group were irrigated with 2%
chlorhexidine solution. for 2 minutes, Each root canal used two chx consepsis which were introduced
via the syringe needle, in group II: Teeth in that group were irrigated with a combination between
ultrasonic + 2% chlorhexidine solution, 2% chlorhexidine solution was introduced directly via the
syringe needle, An ultrasonic tip activated by ultrasonic device (Satelec, France) was placed in the
canals, in group III: Teeth in that group were treated by photodynamic therapy (PDT) (laser + photo
sensitizer agent), (PDT solution: i.e. tolonium chloride) a vital stain was added to fill the canals, A
low power laser diode (Aseptim) (660nm) was applied on the photosensitizer for 2 minutes through
an optical fiber handpiece, Power was set at 100 mw and irradiation time was 2 minutes, The
handpiece was gently moved up and down in the canal during irradiation.Antibacterial efficacy was
assessed before and after treatment. These samples were cultured on KF streptococcus agar media,
incubated for two days then colony forming units were counted. Under the experimental conditions
tested, the antibacterial efficacy of photodynamic therapy against E.faecalis provided a better effect
than chiorhexidine or ultrasonic + chlorhexidine. However there was no statistically significant
difference among the different groups. All the tested materials were effective, 2% Chlorhexidine
reduced E.faecalis by 99.69%, while chlorhexidine & ultrasonic reduced bacteria by 99.71% and
the photodynamic therapy (low power diode laser) with output power 100mw for 2 min possess an
excellent antibacterial efficacy by 99.69%. PDT was effective for reducing E.faecalis in root canals
and could be an adjunct to endodontic treatment.

The aim of this study was to evaluate the effect of low-level laser therapy
(LLLT) on new bone formation obtained by distraction osteogenesis in the early
consolidation period. Ten selected patients with bilateral mandibular retrusion seen
at the Nasser Institute Hospital, Egypt between June 2009 and June 2012 underwent
this clinical trial; seven were female and three were male, and their mean age was
31  5.1 years. The left mandible of each patient was assigned to group A (n = 10)
and the right mandible to group B (n = 10); mandibular distraction osteogenesis was
performed on both sides and then LLLT was used in group B only. The amounts of
bone acquired were compared according to their radiographic density on digital
panoramic radiographs after 6, 12, 24, and 54 days of consolidation. Statistically
significant differences in bone density were found between the two groups. Group B
showed bone consolidation and growth differences on day 6 (P = 0.402), day 12
(P = 0.006), day 24 (P = 0.021), and day 54 (P = 0.028). The use of LLLT on
distracted bone was found to increase the quality and quantity of bone and to shorten
the consolidation period, allowing early removal of the distractor and resulting in
decreased morbidity and relapse.

Aim: This study aimed to assess the biological response of dog dental pulp to 532 nanometer (nm) diode laser compared to 0.9% saline and 2.5 % sodium hypochlorite (NaOCl) used to control infection and bleeding after being capped with Mineral Trioxide Aggregate (MTA).
Methods: Sixty teeth of six dogs, including anteriors and premolars were used. After general and local anesthesia, class V cavity was prepared and the pulp was exposed. Pulp exposure sites were randomly divided into three equal groups 20 teeth each, according to the method of achieving disinfection and haemostasis; 532 nm diode laser with 1 Watt power and exposure time 30 seconds, 0.9% saline and 2.5 % NaOCl. Each group was subdivided into two subgroups according the time of MTA application; 6 and 12 weeks. The exposure sites were then sealed with MTA and restored with composite resin. The animals were sacrificed at 6 and 12 weeks and the teeth were extracted and prepared for haemotaxylen and eosin staining. The pulps of the teeth were examined for the presence of the followings: inflammatory cells, pulp necrosis, pulp calcification, and dentin bridge formation. The number of inflammatory cells and thickness of dentin bridge was measured in ten areas of the histological sections that were randomly chosen for each tooth along the whole length of pulp and the whole length of the dentin bridge at high power field (x200) and the mean value was obtained.
Results: All experimental groups showed chronic inflammatory cells infiltrate with the intensity decrease as time elapsed. Pulp tissue necrosis and calcification weren’t observed at any teeth. On 6 weeks, 7 teeth in group 1 and 6 teeth in both groups 2 and 3 showed dentin bridge formation. While at 12 weeks, all specimens showed dentin bridge formation which was more continuous and thicker than that observed in the 6 weeks. However, the continuity and thickness were considerably variable between different groups. There was a significant difference in the number of inflammatory cells and dentin bridge thickness between the groups at both observation periods (P ≤ 0.005). Statistical evaluation of inflammatory response showed that group 1 was significantly different from groups 2 and 3 separately with lower inflammatory cell response (P ≤ 0.005) and significant differences were detected between the other two groups (P ≤ 0.005). Significant differences in the thickness of dentin bridge were detected in two -by- two comparison between the three groups with group 1 showed the greater thickness and group 2 demonstrated the lowest thickness (P ≤ 0.005).