“…Moreover, given the difference in texture and density between the alveolar ridge and maxillary sinus wall, most surgeons would be able to visualize the sinus with its transparent nature. There are at least 13 studies that also measured the distance between the sinus floor and the PSAA ( Hur et al, 2009 , Jung et al, 2011 , Park et al, 2012 , Kang et al, 2013 , Apostolakis and Bissoon, 2014 , Watanabe et al, 2014 , Yang and Kye, 2014 , Kawakami et al, 2019 , Bedeloğlu and Yalçın, 2020 , Karslioglu et al, 2020 , Fayek et al, 2021 , Laovoravit et al, 2021 ).…”