The impact that Polymerase Chain Reaction (PCR) has had and continues to have in the world of dental and medical biological scientific research is probably second to none. The inventor of this technique, Kary Mullis, is certainly a very particular figure in the scientific field, and without any doubt also deeply divisive, with his unconventional ideas - to say the least -regarding various topics. Here we want to briefly review the life of Kary Mullis and his contribution to scientific progress in dental and medical sciences.
The dentistry history is a part of the history of medicine and the study of historical developments in dentistry, including biographies of people who influenced dentistry in their time. This story extends far into the past. In Denmark, evidence of the opening of a molar dates back to the Neolithic period.
The conservative treatment of the teeth among the ancient farmers of Pakistan could be evidenced in the period from 7000 to 5500 BC., and this with the intention of "repairing" the teeth and possibly filling the cavities (holes drilled in the tooth), too. Since the Sumerians, and until modern times, it was believed that a worm in the tooth was responsible for tooth decay. The first work on dental technology was done by the Etruscans and the Phoenicians. The influence of Roman and Greek scholars was decisive in the Middle Ages both in the Christian and in the Arab world. The Arab discoveries reached the Western world, where the profession of dentist
was practiced by barbers, along with other knowledge from Antiquity, the School of Translators of Toledo and Salerno. At the beginning of the 18th century, science lays the foundations of dentistry in modern times.
Background: The respiratory symptoms of COVID-19 often persist in most patients with moderate to severe infection after recovery. Respiratory exercises help post COVID-19 in pulmonary recovery/rehabilitation. Aim: investigate the effect of incentive spirometer on post-COVID-19 patient’s respiratory outcomes. Hypothesis: patients who had successfully used the incentive spirometer will have better respiratory outcomes 6 weeks after the isolation period. Design:Quasi experimental research design (pre and post-test- time serial). Subjects: 30 adult male and female patients with COVID-19 in a convalescent stage. Sample: Apurposive sample. Setting: one of the COVID 19 follow-up outpatient clinics. Results: the mean age of the studied sample was 47 ±2.984. Half of the studied sample had no chronic diseases and 16.7%had a history of hypertension. The majority of the studied sample 90.7% had dyspnea in the first assessment as compared to 40% in the fourth assessment. The current study represents a highly significant statistical difference between the four assessments regarding the numerical Dyspnea Scale and Modified Medical Research Council (mMRC) Dyspnea Scaleandthe use of incentive spirometer (χ2 = 74.98, df=21, P <0.001), (χ2=23, df=3, p=0.001), (χ2 =36.08, df=4,P<0.001)respectively, as well as a highly negative significant statistical correlation between incentive spirometer capacity and the Numerical Dyspnea Scale (rs = -0.867, P<0.001)and a moderate significant statistical negative correlation between incentive spirometer capacity and Modified Medical Research Council (mMRC)rs= -0.672/P=<0.001).and a moderate significant statistical negative correlation between incentive spirometer capacity and age (r= -0.491/P=<0.001). Conclusion:Respiratory exercises using an incentive spirometer have a positive effect on improving respiratory outcomes and decreasing the severity of dyspnea of post COVID 19 patients who had persistent pulmonary symptoms during the recovery phase. Recommendations:Further studies are necessary to establish whetherincentive spirometer is effective for the respiratory rehabilitation of COVID 19 patients.