‘Malpractice’ means failure on the part of a dentist to exercise the degree of care, diligence and skill ordinarily exercised by dentists in good standing in the community in which he or she practices. As used in this section, ‘community’ means the entire area customarily served by dentists among whom a patient may reasonably choose, not merely the particular area inhabited by the patients of that individual dentist or the particular city or place where the dentist has an office.