Mapping the effect of drugs on ACE2 as a novel target site for COVID-19 therapy.

Angiotensin converting enzyme 2 (ACE2) has potentially conflicting roles in health and disease. COVID-19 coronavirus binds to human cells via ACE2 receptor, which is expressed on almost all body organs. Boosting the ACE2 receptor levels on heart and lung cells may provide more cellular enter to virus thereby worsening the infection. Therefore, among the drug targets, ACE2 is suggested as a vital target of COVID-19 therapy. This hypothesis is based on the protective role of the drugs acting on ACE2. Therefore, this review discusses the impact and challenges of using ACE2 as a target in the current therapy of COVID-19.

Temporomandibular joint alloplastic reconstruction of post-traumatic joint degeneration with Sawhney Type I ankylosis using 3D-custom GD-condylar cap prosthesis to restore condylar form and function.

Temporomandibular Joint (TMJ) ankylosis as a sequelae following hemarthrosis from trauma, middle ear infection and progressive debilitating arthritis of various etiologies has been well understood, but challenges always arise in terms of choosing least morbid procedure with maximum functional outcome. Total joint replacement (TJR) is the common final stage correction mandating extensive surgical exposure with good technical expertise with its limitations of risk of failure and complications. A case of post-traumatic TMJ degeneration with ankylosis reconstructed using a customised GD-condylar cap prosthesis is described. The patient had an uneventful post-operative period with an acceptable functional outcome. CONCLUSION: The condylar cap prosthesis is a bio-compatible and biomechanically designed in such a way that it can be used for indicated cases by performing minimally invasive surgical technique to achieve an optimal functional and aesthetic outcome.

Comparison of latency and efficacy of twin mix and modified twin mix in impacted mandibular third molar surgery - A Preliminary Randomized Triple Blind Split Mouth Clinical Study.

INTRODUCTION: Intra-space drug administration have recently gained popularity in the clinical practice posing several advantages over the conventional routes of drug administration. A preliminary prospective randomized triple blind clinical study was conducted to compare the latency and duration of anesthesia with twin mix (1.8ml 2% lignocaine with 1:200,000 epinephrine and 1ml/4mg dexamethasone) and modified twin mix (1.7ml of 4% articaine with 1:100,000 epinephrine and 1ml/4mg dexamethasone) to two conventional local anesthesia solutions along with co-relation of clinical effects in the postoperative phase in patients undergoing extraction of impacted mandibular third molars in terms of patients comfort post-surgery. MATERIALS AND METHODS: The study was conducted among 20 patients with bilateral impacted mandibular third molars who were randomly allotted to two groups, Group A and B. Each patients in both the groups was allotted with study and control site. Among Group A, patients were further divided into Sub-group L (Control) and Sub-group TM (Twin Mix). Group B patients were divided as Sub-group A (Control) and sub-group MTM (Modified Twin Mix). Sub-group L patients received 1.8ml of 2% lignocaine with 1:200,000 adrenaline and sub-group TM received twin mix. Sub-group A received 1.7ml of 4% articaine with 1:100,000 adrenaline and sub-group MTM received modified twin mix solution. All the procedure was performed by a single operator with a gap of 1 month between the two interventions among both the groups. Various subjective and objective parameters were measured pre-operatively and postoperatively to assess the latency and efficacy of various anesthesia solutions used in this study for third molar removal. RESULTS: Mean (±SD) VAS scores for sting on injection and pain were found to be less in TM and MTM sub-group with a score of 2.3 (±0.768) and 2.7 (±0.065) respectively. The anesthetic latency was significantly less in sub-group TM, with a mean (±SD) of 52.4 (±28.3) seconds. Sub-groups A and MTM had longer latency of anesthesia when compared with L and TM sub-groups. The duration of soft tissue anesthesia was maximum in sub-group MTM as compared to the other sub-groups. Patients from control sub-groups among both the groups had increased swelling, post-surgical pain and trismus postoperatively. DISCUSSION: Intra-space administration of twin mix and modified twin mix is clinically efficacious in impacted mandibular third molars surgery with better clinical outcomes postoperatively. We observed one significant difference between TM and MTM that the latter solution provided a prolonged duration of anesthesia increasing the patient's comfort postoperatively after surgical removal of mandibular third molars.

A three dimensional (3D) musculoskeletal finite element analysis of DARSN temporomandibular joint (TMJ) prosthesis for total unilateral alloplastic joint replacement.

PURPOSE: The purpose of this study was to evaluate the strain and stress distribution for DARSN alloplastic unilateral temporomandibular joint (TMJ) prosthesis and the effects on contralateral natural joint using a finite element analysis (FEA). METHODS: The replacement of the TMJ may have complications like infection, failure of hardware, facial paralysis and perforation. The understanding of the mechanical forces exerted by muscles of mastication and jaw movement on the joint helps in identifying the regions on alloplastic TMJ with various maximum forces, which makes that area more prone for failure of hardware. A three dimensional structural FEA was applied using a validated finite element model (FEM) where the areas of stress and strain were evaluated in the alloplastic joint and the contralateral natural joint. As the pattern of stress and strain can be influenced by the materials used for alloplastic joint and geometry of the design, mechanical property of bone and the attached musculature were also considered while construction the FEM analysis. RESULTS: The forces of the muscles of mastication has a vital role on the amount of stress and strain present across the alloplastic joint. Masseter and temporalis exhibited the greatest resultant force on the alloplastic as well as the natural condyle with a magnitude of 272 N and 329 N. This study assessed the maximum stress and strain on the condyle-ramus unit and fossa. CONCLUSION: FEA shows that alloplastic DARSN TMJ prosthesis distributes stress and strain equally between the alloplastic joint site and the contralateral natural joint causing minimal adverse effects to the natural joint. FEA also evaluated the stress and strain on alloplastic component and resulted in drawing clinical implications for operating surgical team.