The accuracy of clinical diagnosis and clinical examinations can have a profound impact on the early detection of potentially malignant lesions. Currently, the standard of care is clinical confirmation of the clinical impression for all medical conditions. Although encouraging early diagnosis through examination and prompt treatment to detect cause is important, it can result in an abundance of correct procedures and patient worry. A little discrepancy between clinical diagnoses can lead to the fatality. An improved understanding of the accuracy of medical conditions of patients is necessary to inform evidence-based treatment recommendations for examination and clinical care. In oral and maxillofacial surgery it is very important to understand and diagnose the underlying medical conditions with the patient chief complaint. An overall general and systemic examination is compulsory needed.