Impacto de COVID-19 en la terapia periodontal: Una visión general.

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Bone Reformative Capability of Nano-chitosan in Rabbits

Aims: To evaluate the ability of natural biomaterial nano chitosan for osteogenic regeneration in rabbit animal models. Materials and methods: Eighteen male domestic rabbits were used in the study the formation of two bony defects was created in the rabbit's femur, one filled with nano chitosan material, and the other defect was left empty as a control. Densitometry and histomorphometric analysis were measured at, 7 days, 14 days, and 28 days which was used as a parameter. Results: The nano chitosan showed lesser radio-opacity than the control with a positive osteogenic effect due to the osteoinduction and osseointegration properties. Conclusions: This study supports that nano chitosan natural polymer may have better application prospects for bone repair and acceleration of the healing process

Evaluation of Clinical Efficacy of Biodegradable Chip Containing Salvadora persica Extract in Chitosan Base as an Adjunct to Scaling and Root Planning in the Management of Periodontitis

Objective: The objectives of this study were to develop two biodegradable periodontal chips containing Salvadora persica or Benzyl isothiocyanate (BITC) extract and evaluate its clinical effectiveness in managing periodontitis. Methods: Chips were formulated from Salvadora persica, Benzyl isothiocyanate (BITC) and chitosan; twelve patients with periodontal pockets measuring ≥5 mm participated in this study. Overall, 240 periodontal pockets were evaluated. All patients were treated with full mouth scaling and root planning (SRP) at baseline. Periodontal pockets were divided into four groups. One of which is the control group, while group two received plain chitosan chip. Group three received chips containing Salvadora persica extract, and group four received chips containing BITC. Plaque index (PI), bleeding on probing (BOP), periodontal probing pocket (PPD) depth, and clinical attachment levels (CAL) using acrylic stents were recorded at days 0 and 60 only. Results: Data were statistically analysed; Chi-square t-test and an ANOVA were used. Results showed significant improvement in plaque index, bleeding on probing, and reduction in periodontal pocket depth in all four groups (p<0.05). The gain in clinical attachment level was significantly higher (p<0.005) among the group receiving Salvadora persica chips compared to the control and other chip-treated groups. Conclusion: Periodontal chips containing S. persica can be used as adjuncts to treat patients with periodontitis. Keywords: Chitosan; Periodontal chip; Miswak extract; Benzyl isothiocyanate; Periodontitis

Osteogenic Regenerative Ability of Hydroxyapatite and Tricalcium Phosphate (Osteon III) in Rabbits

Aims: Bone loss beyond the body's ability to regenerate may occur from various causes. The conventional methods of bone repair commonly used, such as autografts and allografts have their shortcomings and drawbacks. So, this study aims to evaluate the ability of biphasic hydroxyapatite and tricalcium phosphate 0steonIII (60% hydroxyapatite /40% tricalcium phosphate) for osteogenic regeneration in a rabbit model. Materials and Methods: Eighteen domestic rabbits were used in the current study. For each rabbit and following intramuscular general anesthesia, the selected site of surgery over the right femur was shaved and cleaned with povidone-iodine. A small incision of about 1.5 cm was created over the femur bone near its head avoiding any trauma to muscle. Two holes of 2 mm in depth and diameter and 15 mm apart were created under copious irrigation with distilled water in the femur. Using a small plastic scoop about 0.0260 g of Osteon III was added directly to fill one hole while the second hole was left empty to be filled with blood. At completion, the wound was closed using sutures. Based on this, the animals were divided into 2 groups and sacrificed at different time intervals at 7 days, 14 days, and 28 days. At the end of the aforementioned time interval, radiographic images of the femoral bones were taken at standard alignment and distance from the X-ray source, and histological assessment was conducted. Results: The osteon III bone defects showed high radio-opacity indicating new bone formation and mineralization due to the osteoconduction properties. Conclusions: This study supports that Osteon III may have better application prospects for bone repair

Utilization of harmonics current in single phase system

© 2016 IEEE. This paper presents a simple method to benefit of the harmonics current which is produced on the source side because of the nonlinear loads in single phase systems. The proposed circuit contributes in reduction of the total harmonic distortion (THD) and draw harmonics current via low pass filter (LPF) and create a useful power by rectifying the distorted current via full wave bridge rectifier (convert it to DC current) and reconvert it to AC sinusoidal current by using single phase inverter controlled by PWM circuit in order to feed different loads. The circuit has been designed and simulated in the MATLAB-Simulink program. It can be concluded from the results of the simulation, that the utilized current (I u ) can be created by rectifying harmonics current I h with simple design and low cost circuit without requiring any additional current drawn from the source and can feed RL-load

In-Vivo Effect of Andrographolide on Alveolar Bone Resorption Induced by Porphyromonas gingivalis and Its Relation with Antioxidant Enzymes

Alveolar bone resorption is one of the most important facts in denture construction. Porphyromonas gingivalis (Pg) causes alveolar bone resorption, and morphologic measurements are the most frequent methods to identify bone resorption in periodontal studies. This study has aimed at evaluating the effect of Andrographolide (AND) on alveolar bone resorption in rats induced by Pg. 24 healthy male Sprague Dawley rats were divided into four groups as follows: normal control group and three experimental groups challenged orally with Pg ATCC 33277 five times a week supplemented with 20 mg/kg and 10 mg/kg of AND for twelve weeks. Alveolar bones of the left and right sides of the mandible were assessed by a morphometric method. The bone level, that is, the distance from the alveolar bone crest to cementumenamel junction (CEJ), was measured using 6.1 : 1 zoom stereomicroscope and software. AND reduced the effect of Pg on alveolar bone resorption and decreased the serum levels of Hexanoyl-Lysine (HEL); furthermore the reduced glutathione/oxidised glutathione (GSH/GSSG) ratio in AND treated groups (10 and 20 mg/kg) significantly increased when compared with the Pg group (P<0.05). We can conclude that AND suppresses alveolar bone resorption caused by Pg in rats

The impact of vitamin D on clinical parameters and bone turnover biomarkers in ligature-induced periodontitis: An experimental study in rats

Objectives and Background: Vitamin D has been associated with an increased risk of tooth loss and the severity of periodontal diseases. This study aimed to evaluate the effect of vitamin D on the clinical, radiographic, and serum level changes of bone turnover biomarkers in ligature-induced periodontitis. Methods: A total of 28 rats were included in this study and divided into test groups: Vitamin D supplement (VS), Vitamin D deficient (VD), and control (CG). Ligature-induced periodontal tissue destruction was performed and kept for 21 days. Clinical attachment and radiographic changes were recorded, and serum samples were tested for Osteoprotegerin (OPG), Dickkopf-1 (DKK1), Sclerostin (SOST), and Fibroblast growth factor 23 (FGF23) on the initial and final day of the study. Results: Groups that were made VD exhibited a more significant amount of clinical attachment loss (1.05 ± 0.50 mm) compared to the CG (0.83 ± 0.14 mm) and VS group (0.60 ± 0.13 mm), showing significant differences (p < 0.05). The radiographic alveolar bone loss amount was greater in the VD group compared to the other groups. For serum level assessment, the VD groups also exhibited a statistically significant reduction in the levels of OPG. They showed higher concentrations of DKK1, SOST, and FGF23 than other groups, with significant differences (p < 0.05). Conclusion: The results revealed that Vitamin D may play a role in the progression of periodontal disease. It was found to affect both clinical parameters and bone turnover biomarkers, suggesting its potential impact on the disease process