Dental hygiene was originated from dentistry and dental hygiene knowledge was a component of dental knowledge body. Since the late 1980s dental hygiene theory was began to develop. Nursing theories such as metaparadigm, nursing process and human need theory affected theory development as dental hygiene process. Dental hygiene process provides a framework for high quality dental hygiene care. Dental hygiene process include five phases; assessment, dental hygiene diagnosis, dental hygiene planning, implementation, evaluation. Dental hygiene process of care is recognized as standard for dental hygiene education and clinical dental hygiene practice. Dental hygiene practice has moved from auxiliary model to professional model. Critical thinking skill and disposition are necessary to provide evidence-based dental hygiene care using dental hygiene process as clinical process and critical thinking process. Critical thinking, problem solving and evidence-based practice must be integrated into dental hygiene process for quality dental hygiene care.