Due to the development of society, the rise of living standards, the increase of population, the availability of information, and the establishment of health care systems, the medical industry is not as prestigious as it was in the past. Under the economy where the market is changing from supplier-oriented to consumer-oriented, competitions between various medical facilities and patients¡¦ demands for better medical care quality grow, which then result in the rise of medical risks. Medical institutions no longer just focus on the treatment effects, but must also fully understand the conditions of the patients and effectively manage and utilize the resources at hand in order to raise the treatment quality and to stand above other competitors. The purpose of this research is to identify the various factors that prompt patients to seek medical treatments, and to raise patients¡¦ satisfaction and faithfulness towards medical institutions. The research was carried out using a survey/questionnaire approach. Patients that have been to two or more dental clinics were asked to participate in the survey, and those who were interested were chosen. The PZB service quality SERVQUAL scale was used. Out of the 150 questionnaires distributed, 123 were retrieved (82%), and 111 of those retrieved were valid for consideration (74%). The survey showed that (1) a gap exists between patients¡¦ expected treatment service and the actual service received; (2) patients hold high expectation towards the service quality; (3) patients decision to switch clinics partially depends on the received service; (4) the main factor that prompt patients to switch clinics is their concerns towards the ability of their doctors/physicians; (5) Instead of the actual service, assurance and reliability are more essential to the patients; and (6) clinics showing sincerity and making sure the patients feel secure are most important towards the patients. The research concludes that patients choose their medical institutions base on the received services. The five aspects of service all have almost equal importance, and all are influential towards patients¡¦ choices of medical institutions.