The potential use of nanozymes as an antibacterial agents in oral infection, periodontitis, and peri-implantitis.

Several studies suggest that oral pathogenic biofilms cause persistent oral infections. Among these is periodontitis, a prevalent condition brought on by plaque biofilm. It can even result in tooth loss. Furthermore, the accumulation of germs around a dental implant may lead to peri-implantitis, which damages the surrounding bone and gum tissue. Furthermore, bacterial biofilm contamination on the implant causes soft tissue irritation and adjacent bone resorption, severely compromising dental health. On decontaminated implant surfaces, however, re-osseointegration cannot be induced by standard biofilm removal techniques such as mechanical cleaning and antiseptic treatment. A family of nanoparticles known as nanozymes (NZs) comprise highly catalytically active multivalent metal components. The most often employed NZs with antibacterial activity are those that have peroxidase (POD) activity, among other types of NZs. Since NZs are less expensive, more easily produced, and more stable than natural enzymes, they hold great promise for use in various applications, including treating microbial infections. NZs have significantly contributed to studying implant success rates and periodontal health maintenance in periodontics and implantology. An extensive analysis of the research on various NZs and their applications in managing oral health conditions, including dental caries, dental pulp disorders, oral ulcers, peri-implantitis, and bacterial infections of the mouth. To combat bacteria, this review concentrates on NZs that imitate the activity of enzymes in implantology and periodontology. With a view to the future, there are several ways that NZs might be used to treat dental disorders antibacterially.

Gingival mesenchymal stem cell therapy, immune cells, and immunoinflammatory application.

MSC-based therapeutic strategies have proven to be incredibly effective. Robust self-renewal, multilineage differentiation, and potential for tissue regeneration and disease treatments are all features of MSCs isolated from oral tissue. Human exfoliated deciduous teeth, dental follicles, dental pulp, apical papilla SCs, and alveolar bone are the primary sources of oral MSC production. The early immunoinflammatory response is the first stage of the healing process. Oral MSCs can interact with various cells, such as immune cells, revealing potential immunomodulatory regulators. They also have strong differentiation and regeneration potential. Therefore, a ground-breaking strategy would be to research novel immunomodulatory approaches for treating disease and tissue regeneration that depend on the immunomodulatory activities of oral MSCs during tissue regeneration.

Efficacy of a mobile phone application for the improvement of oral hygiene of patients undergoing fixed orthodontic treatment : A randomized controlled clinical trial.

OBJECTIVES: This study aimed to assess the efficacy of a mobile phone application (app) to improve oral hygiene of patients undergoing fixed orthodontic treatment. MATERIALS AND METHODS: This randomized controlled clinical trial was conducted with a total of 60 patients undergoing fixed orthodontic treatment in two groups: intervention and control (n = 30 each). A previously designed mobile app (Labkhand) was used by patients in the intervention group. Orthodontic plaque index (OPI) and modified gingival index (MGI) were recorded in the two groups at baseline (first session or T0), and after 1 (T1) and 3 (T2) months. The number of debonded/broken brackets was also recorded, and pain score of the patients was assessed at nine time points. Data were analyzed using the χ2 test, paired t­test, and repeated measures analysis of variance (ANOVA; α = 0.05). RESULTS: The two groups demonstrated no significant difference in OPI and MGI at T0 (P > 0.05). OPI and MGI at T1 and T2 were significantly lower in the intervention group than in the control group (P < 0.05). The number of patients with broken brackets in the intervention group was significantly lower than that in the control group (P = 0.017). The two groups reported no significant difference in pain score (P > 0.05). CONCLUSION: The Labkhand mobile app successfully improved oral hygiene indices of patients undergoing fixed orthodontic treatment, and decreased the frequency of broken brackets after 1 and 3 months of use.

Cytotoxicity of PLGA-zinc oxide nanocomposite on human gingival fibroblasts.

Background: Polylactic-co-glycolic acid and zinc oxide (PLGA-ZnO) nanocomposite has been investigated for its antibacterial properties, which could be beneficial for adding to wound dressings after periodontal surgery. However, its cytotoxicity against human gingival fibroblasts (HGFs) remains unclear and should be evaluated. Methods: ZnO nanoparticles were synthesized using the hydrothermal method. These metallic nanoparticles were incorporated into the PLGA matrix by the solvent/non-solvent process. The nanomaterial was evaluated by field emission scanning electron microscopy (FESEM), Fourier transform infrared (FTIR), thermogravimetric analysis (TGA), and x-ray diffraction (XRD) analyses. HGF cells were acquired from the National Cell Bank and categorized into four groups: ZnO, PLGA, ZnO-PLGA, and control. The cells were exposed to different ZnO (1, 20, 40, 60, 80, and 100 µg/mL) and PLGA (0.2, 4, 8, 12, 16, and 20 µg/mL) concentrations for 24 and 48 hours. The cytotoxicity was tested using the MTT assay. The data were analyzed using SPSS 25, and P<0.05 was considered statistically significant. Results: ZnO nanoparticles exhibited significant toxicity at≥40 µg/mL concentrations after 24 hours. Cell viability decreased significantly at all the tested concentrations after 48 hours of exposure. PLGA-ZnO cell viability in 24 hours was similar to the control group for all the concentrations up to 80 µg/mL. Conclusion: ZnO nanoparticles could be toxic against HGF in high concentrations and with prolonged exposure. Therefore, incorporating ZnO nanoparticles into a biocompatible polymer such as PLGA could be a beneficial strategy for reducing their toxicity.

Stress Distribution in Peri-implant Bone in the Replacement of Molars with One or Two Implants: A Finite Element Analysis.

Statement of the Problem: In most cases, insertion of single implants with a standard diameter is used to replace a molar tooth but placing two implants with a narrow diameter seems to be a viable treatment modality to withstand functional and biomechanical forces. Purpose: This study aimed to evaluate and compare stress distribution in the bone surrounding a single molar area rehabilitated by a single implant versus two implants with a narrow diameter. Materials and Method: The study was conducted by computer-aided in vitro modeling. The initial model used a single implant, 4.8 mm wide in diameter, inserted with a 3.9-mm distance from both sides and 12.6-mm mesiodistal space. The second model used two 3.3-mm narrow-sized implants with a 3-mm distance from one another, 1.5 mm from both sides, and a 12.6-mm mesiodistal space. Following the completion of these models, a 100-N force was exerted obliquely, once in three locations and once in the mesial aspect of the implant-supported crown. Stress distribution was then measured using finite element analysis (FEA) with ANSYS Workbench software package in both models. Results: The maximum stress in the bone around the single implant was less than that around double implants. The maximum stress of cortical bone in three-point loading was lower than mesial loading either in one (146.7 vs. 126.72 MPa) or two implants model (186.8 vs. 139.24). Conclusion: According to the results, because of more cortical bone contact area, the stress of surrounding bone in wide implant was decreased.

The Effect of Non-Surgical Periodontal Therapy on Pentraxin-3 Concentration in Gingival Crevicular Fluid of Chronic Periodontitis Patients: A Clinical Trial.

Statement of the Problem: Periodontitis is a multifactorial disease caused by periopathogens and its severity is determined by the host immune response. Gingival crevicular fluid (GCF) can be used for non-invasive testing to assess the host response in periodontal treatment. Pentraxins are the classic mediators of inflammation and pentraxin-3 can be used as a marker to assess response to therapy, which was investigated in this study. Purpose: This study aimed to assess the effect of non-surgical periodontal therapy on GCF level of pentraxin-3 in patients with chronic periodontitis. Materials and Method: 25 patients with chronic periodontitis (CP) and 25 periodontally healthy controls were evaluated. Pocket probing depth, clinical attachment loss, plaque index, gingival index, and bleeding on probing were measured in both groups. GCF samples were collected using paper strips to assess the level of pentraxin-3. In the CP group, GCF samples were collected from the highest clinical attachment loss, pocket probing depth, and bone loss at baseline and six weeks after non-surgical therapy. The level of pentraxin-3 in the GCF was quantified by enzyme-linked immunosorbent assay (ELISA). Data were analyzed using SPSS version 23. Results: Pentraxin-3 in GCF of CP patients before treatment (6.72±4.63 ng/mL) was higher than the control group (4.43±2.85 ng/mL). Pentraxin-3 in patients after non-surgical therapy (3.2±2.66 ng/mL) decreased significantly compared to the baseline (p= 0.04) and its level after treatment was not significantly different from the control group (p= 0.14). Conclusion: Pentraxin-3 in GCF of CP patients was higher than healthy controls and decreased in response to non-surgical periodontal therapy. Thus, it can be used as an inflammatory marker for detection of patients at risk of CP. However, further studies with larger samples and longer follow-ups in different populations are required to confirm our findings.