The present disclosure relates to a method for self-investigating an optical element embedded in an intraoral scanner, and a system using the same. The reliability of an intraoral scanner may decrease due to foreign matter attached to an optical element. Accordingly, the present disclosure provides a prescribed method for investigating foreign matter attached to an optical element, and a system using the same, wherein an alarm providing notification of the need to inspect the optical element is generated when it is determined that foreign matter has stained the optical element. According to said investigation method and system, a user of an intraoral scanner can automatically determine the presence or absence of foreign matter when scanning an object (patient's affected area), and thus can service the optical element or replace a part in which the corresponding component is formed. Therefore, there is an advantage of improving the scanning efficiency and data reliability of the intraoral scanner.

Provided is an adapter for connection to a spray can dispensing an oil-containing aerosol. The adapter comprises a timepiece configured to measure a predetermined time interval, the starting point of the time measurement being defined by the start of a spraying process of the spray can; and an indicating element configured to indicate to the user, once the predetermined time interval has expired, to end the spraying process. Also provided is a method for manually reprocessing a medical device.