Over the decades, the demand for teeth whitening has increased which has prompted the creation of numerous novel bleaching products. A teethwhitening product called Synergy gel makes claim to cause no signicant sensitivity, is highly effective, has ease of handling, and is used without a gingival barrier. Hence, this study is to evaluate the efcacy of teeth-whitening agents with and without the use of a diode laser. The teeth Method: in this split-mouth design were grouped into group A (Novo Synergy tooth whitening with an 810nm diode laser) and group B (Only Novo Synergy tooth whitening). There is a signicant difference between both groups at imme Result: diate and 15 days. But, there is no signicant difference between both groups at 3 months. The use of diode lasers (810nm) to enhance bleaching ha Conclusion: s signicant efcacy to that of the synergy gel bleaching but for a shorter period of time.

The whole world is under the grip of a pandemic of COVID-19, a disease caused by a newly discovered strain of coronavirus and the name given is SARS-CoV-2. The term 'novel' is used for this virus because researches suggest that its origin is from an animal which was transmitted to a human and now is capable of having transmission from human to human. Symptoms of COVID-19 can be mild to severe. Mortality is high in severe cases. Also, this virus is a serious threat to the elderly and people with other systemic illness. There is no specific protocol provided for its treatment and the treatment primarily focuses on symptomatic relief. Human immune systems have never come across this particular type of strain of virus before. As a result, human body has not developed immunity for it moreover no effective vaccine is developed for it at this point of time. But there is an active strenuous work going on to understand more and more about the interaction of host-pathogen, how does host immunity responses to this virus moreover how this pathogen is able to invade the immune system which can be utilised for the development of a vaccine. As the disease is highly infectious, there is an urgent need for the development of a vaccine. Hence this review aims to summarize the undergoing scientific work and research in progress for the development of vaccine and all the advancement that has come in focus for its development.