As the computer science is advancing, a lot of professions tend to computerize or digitalize the daily process. In terms of dentistry, computerize is necessary. In recent years, digitalization is one of important tendency that motivates orthodontists to apply the computer techniques into clinical in order to improve the quality of data management. However, not every dentist is familiar with the computing skill and knowledge. Thus, choosing a useful portable storage device becomes extremely important for collect, storage, protect and analyze the information. Most consumers tend to ignore the practicability and usefulness of products when the time comes to decide what to buy. Therefore, the practicability is the most important principle to select appropriate hardware. When the time comes to decision making, it is extremely important to precisely measure what the really needs are and how to better meet the requirements proposed to choose proper facilities at a tolerating price.