RESUMO
@#Optical illusion refers to the phenomenon in which the scene observed by the human eye is not completely consistent with the objectively presented scene. Optical illusions in stomatology, as well as their clinical application, are demonstrated in this paper in terms of shade, shape and aesthetic design. Shade is not only affected by the optical illusions with which it is associated, such as color metamerism, color constancy and the Chevreul illusion, but also influenced by the surroundings. It is suggested that the surrounding lighting during veneering should be the same as that during color matching in the clinic. As indicated by the Poggendorf illusion and the Leaning Tower illusion, the practice should be conducted and checked from multiple perspectives to compensate for the limitation of human eyes, such as intraoral scanning. Other digital technologies, including digital facial scanning and cephalometric measurement, could be used to reduce the subjective influence of observation. In terms of esthetic design, the interaction of the part and the whole, suggested by Ebbinghaus illusion, should be considered: an individual harmony smile should be designed considering the characteristics of the personality and the features of the face, lips, teeth and gingiva of the patient. Furthermore, personal information, such as gender and age, should be taken into consideration in beautification presentation. Further research should be focused on the influence of optical illusions in stomatology in more details. More communication among doctors, technicians and patients is needed. Clinicians should be aware of the impact of optical illusions to reduce subjective bias in clinical standardized operations and further take advantage of optical illusions to create beautification presentations of dental restorations and smiles.
RESUMO
Amicroscope (from the Ancient Greek, mikrós, ‘small’ and skopeîn, ‘to look’ or ‘see’) is an instrument used to see objects that are too small for the naked eye. The science of investigating small objects using such an instrument is called Microscopy. Microscopic means invisible to the eye unless aided by a microscope. There are many types of microscopes. The most common (and the first to be invented) is the optical microscope, which uses light to image the sample. Other major types of microscopes include the electron microscope (both the transmission electron microscope and the scanning electron microscope), the ultra-microscope, and the various types of scanning probe microscopes[1, 2]. The first microscope to be developed was the optical microscope, although the original inventor is not easy to identify. Evidence points to the first compound microscope appearing in the Netherlandsin the late 1590s, probably an invention of eye glassmakers there[3], Hans Lippershey (who developed an early telescope) and Zacharias Janssen (also claimed as the inventor of the telescope). There are other claims that the microscope and the telescope were invented by Roger Bacon in the 1200s[4], but this is not substantiated. Giovanni Faber coined the name microscope for Galileo Galilei's compound microscope in 1625[5]. (Galileo had called it the ‘occhiolino’ or ‘little eye’.)