Effect of photobiomodulation therapy on TGF-ß release from dentin, migration and viability of dental pulp stem cells in regenerative endodontics treatment: An ex vivo study.

BACKGROUND AND AIM: Regenerative endodontic procedures (REPs) are oriented by the principles of tissue engineering, incorporating dental pulp stem cells (DPSC), crucial growth factors like Transforming growth factor-ß (TGF-ß1), and scaffolds to facilitate the regeneration of dental pulp tissues. The present study aimed to investigate the effect of photobiomodulation (PBM) therapy, using an 808 nm diode laser on cellular modulation mechanisms in REPs. METHOD AND MATERIAL: A total of 108 human dentin discs obtained from intact single root teeth were randomly assigned into six groups (n = 8): 1. Positive control (EDTA), 2. PBM-1 (3 J/cm2), 3. PBM-2 (5 J/cm2), 4. EDTA+PBM-1, 5. EDTA+PBM-2, and 6. Negative control (NaOCl). Then, an extract solution was prepared from each disc and the concentration of released TGF-ß1 from the discs was measured using enzyme-linked immunosorbent assay (ELISA). Moreover, the extract solution was added to DPSC culture medium to evaluate cell viability and migration through MTT assay and scratch test, respectively. RESULT: The group exposed to PBM-1 showed the highest cell viability, while treatment with EDTA and EDTA+PBM-2 decreased cellular viability. Also, the PBM-treated groups showed significantly higher release of TGF-ß1 compared to the negative control. EDTA and EDTA+PBM-1 showed the highest release among all the groups. No significant difference was found between EDTA and EDTA+PBM-1, as well as between PBM-1 and PBM-2. Moreover, the PBM-1 group exhibited the highest migration after 24 h, which was significantly greater than other groups, except for the PBM-2 group. CONCLUSION: According to the obtained data, 808 nm mediated-PBM (3 J/cm2), both independently and in conjunction with EDTA, enhanced the release of TGF-ß1 from dentin and improved cell viability and migration of DPSCs. It seems that, PBM under the specific parameters employed in this study, could be an effective adjunctive therapy in REPs.

Diagnosis and Treatment of an Incomplete Crown-Root Fracture with Intentional Replantation: A Case Report.

Acute traumatic injuries to the maxillary incisors may lead to a crown-root fracture. If the fracture is left untreated, the fracture line will propagate and extend apically, resulting in microbial contamination of the attachment apparatus and subsequent bone loss. In cases with extensive periodontal involvement, extraction has been suggested. However, bonding and sealing the fracture line with a biocompatible material seems to be an effective alternative treatment option. In this case report, management of a central incisor with an incomplete crown-root fracture that showed signs and symptoms of vertical root fracture is discussed. As the extension of the fracture line was not clear, intentional replantation and sealing the fracture line with a glass ionomer was performed. The tooth showed no signs and symptoms at six-month follow up, and the radiographic examination exhibited substantial bone repair.

Mandibular Second Premolar with Four Canals: A Case Report.

The mandibular second premolar can be considered one of the most challenging teeth to treat endodontically; due to the complexity of its root canal morphology and increased incidence of multiple canals. The knowledge of internal anatomy of root canals and their possible variations as well as use of magnification, e.g. operating microscope, radiographic examination and illumination, can increase the chances of finding additional canals and contribute to the success of endodontic treatment. The purpose of the current investigation is to report the successful endodontic treatment of a mandibular second premolar with 4 canals; all of them in one single root.

Management of a Large Periapical Lesion Using Decompression: A Case Report with Three-year Follow-up.

Large radicular lesions should be treated initially by orthograde root canal therapy. When the signs and symptoms of the infection (e.g. persistent purulent drainage) do not resolve after this treatment, then surgical approaches should be considered. In the cases of large radicular cysts, total enucleation of the cyst can endanger adjacent structures and teeth. Therefore, decompression or marsupialization techniques are recommended in order to decrease the size of the lesion. In this case report, a 55-year-old woman with previously initiated therapy was referred to endodontic department for management of a sinus tract associated with tooth #7. Root canal treatment was performed and intracanal irrigant (5.25% sodium hypochlorite) activated using passive ultrasonic application, various intracanal medicament (calcium hydroxide, double antibiotic paste) was used in multiple sessions, but intracanal purulent drainage was not resolved. After this, decompression was performed using needle cap to maintain the opening of the cyst and remained for three months. During this period the cavity was kept clean and rinsed by the patient with 0.2% chlorhexidine mouthwash. After three-year follow-up, radiographic examination revealed substantial osseous repair of the defect and clinical signs and symptoms were absent.

Effect of photobiomodulation on pain level during local anesthesia injection: a randomized clinical trial.

The aim of this study was to investigate the effect of photobiomodulation therapy (PBMT) as pre-treatment on pain level during injection in the anterior maxillary region. 56 Patients were randomly divided into 3 groups, Group 1:980 nm diode laser (n = 22) (experimental), Group 2:980 nm diode laser probe placed in vestibule without radiation (placebo) (n = 22), Group3: no pre-treatment before injection (n = 12) (control). Pain level during injection was evaluated by visual analog scale (VAS). The severity of pain in Group 1(experimental) and Group 2 (placebo) was significantly lower than Group 3 (control). Group 1 had a lesser pain level than Group 2, but the difference in pain level between them was not significant. PBMT with 980 nm wavelength decreased pain level during local anesthesia injection without superiority over placebo.

Effect of ultrasonic activation on the efficacy of antimicrobial photodynamic therapy: Evaluation of penetration depth of photosensitizer and elimination of Enterococcus faecalis biofilms.

BACKGROUND: This study aimed to assess the effect of ultrasonic activation of photosensitizer on the efficacy of Antimicrobial Photodynamic Therapy (aPDT) against Enterococcus faecalis and penetration depth of photosensitizer. MATERIALS AND METHODS: In this ex vivo study, mature microbial biofilm of E. faecalis was formed in the root canals of 58 single-rooted single-canal mandibular incisors following their decoronation. The roots were longitudinally sectioned by a diamond disc and split into halves by a chisel. The E. faecalis biofilm was quantified and the penetration depth of photosensitizer was determined by the microbial viability assay and stereomicroscopic analysis in the following three study groups: (1) Ultrasonically activated 5.25% sodium hypochlorite (NaOCl) for 20 s, (2) aPDT using methylene blue (MB) plus 660 nm diode laser with 150 mW power for 1 minute, and (3) ultrasonically activated MB for 20 s followed by aPDT as in group 2. Independent sample t test and one way ANOVA were used to compare the dye penetration depth and microbial load, respectively in the apical and coronal regions among the groups. RESULTS: The penetration depth of photosensitizer in group 3 was significantly greater than that in group 2 (P < 0.05). The E. faecalis count in all three experimental groups was significantly lower than that in the control group (P < 0.05). Groups 1 and 3 were significantly superior to group 2 in terms of reduction in microbial count but the difference between groups 1 and 3 was not significant (P > 0.05). CONCLUSION: Ultrasonic activation of photosensitizer in aPDT increases the penetration depth of photosensitizer into the dentinal tubules and enhances its antibacterial activity. HIGHLIGHT: Ultrasonic activation of photosensitizer in aPDT enhances its penetration depth into dentinal tubules and increases antibacterial efficacy. There was no significant difference between antibacterial effects of aPDT + ultrasonic and ultrasonic activated NaOCl.