Oral pathology deals with diseases affecting the oral and maxillofacial regions. It involves research, diagnosis, and patient management. Diseases are classified based on the affected tissue, such as hard tissues like teeth and bones, or soft tissues. Diagnosis depends on clinical features, radiographic or microscopic examination of biopsied tissues. Common diagnostic tools include exfoliative cytology, vital dyes, and biopsy of lesions. Biopsied tissues undergo fixation, processing, sectioning and staining for microscopic examination by a pathologist.