Combination of Dental-Capping Agents with Low Level Laser Therapy Promotes Proliferation of Stem Cells from Apical Papilla.

Background: Direct pulp capping is a vital pulp therapy, which stimulates differentiation of stem cells from apical papilla (SCAPs). SCAPs have multipotential capacity to differentiate into types of cells, contributing to the regeneration of tissues. Objective: Considering the promising effects of dental-capping materials, we aim to investigate the effect of dental dressing materials combined with laser therapy on the percentage of SCAP viability and the consequent dental regeneration capacity. Methods: We collected two immature third molar teeth and isolated SCAPs through collagenase type I enzymatic activity. Isolated SCAPs were then cultured with Dulbecco's modified Eagle's medium and α-minimum essential medium enriched with 15% and 10% fetal bovine serum, respectively. After reaching 70-80% confluency, cells were seeded in a 96-well plate and then treated with mineral trioxide aggregate (MTA), enamel matrix derivative (EMD), biodentine, and low level laser therapy (LLLT) alone and in combination for 24, 48, and 168 h. After that, cell survival rate was assessed using (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) assay. Results: We found that combination of MTA, EMD, and LLLT as well as that of biodentine, EMD, and LLLT could lead to significant increase of SCAP viability as compared with other treatment groups. Combination of MTA and biodentine with EMD could also show increased level of SCAP proliferation and viability. However, MTA and biodentine alone reduced SCAP survival rate in all time points. Conclusions: Our conclusion is that LLLT can serve as an enhancer of SCAP proliferation and differentiation rate when added to dental-capping agents such as MTA, EMD, and biodentine. Thus, LLLT combination with effective capping materials will serve as a promising option for dental tissue repair.

The effect of cisplatin-low-level laser therapy on cell viability and death of LNCaP prostate cancer cell line.

Prostate cancer, as a common male cancer, is a serious threat to men's health. In spite of extreme developments for increasing survival rate, there are still limitations about common treatment options such as surgical procedures, radiotherapy, and chemotherapy. We hypothesized that combination of two treatments would bring better clinical outcomes. Therefore, the aim of this study was to determine the effect of conjugated cisplatin and low-level laser treatment (LLLT) on the viability of LNCaP prostate cancer cell line. LNCaP cells were harvested in DMEM containing 10% FBS and 1% antibiotic. Confluent cells were treated with different concentrations of cisplatin and different wavelengths of low-level laser (LLL) alone and in combination. The relative IC50 and cell viability was evaluated using MTT assay. Analysis of lipid peroxidation rate was performed using lipid peroxidation assay kit. LDH activity was also carried out on the treated and control cells using LDH cytotoxicity assay kit. Our results showed that combination of cisplatin and LLLT could effectively decrease cisplatin-induced cytotoxicity as well as LNCaP cell viability. Cisplatin-LLLT combination led to a significant increase in the MDA content as the product of membrane lipid peroxidation. Analyzing the LDH activity under the effect of cisplatin-LLL combined treatment showed a remarkable increase in the enzyme activity. We conclude that applying the cisplatin-LLL combination therapy is promising as an effective anti-cancer treatment. This novel combination has a potential to attenuate adverse side effects of earlier monotherapy strategies.