A toothache is usually caused by tooth decay or infection and can be triggered by various factors like decay, abscesses, injuries, or fractures. Tooth fractures occur from activities like contact sports or chewing hard things and can range from minor cracks to serious fractures. Knocked out teeth result from impacts to the mouth and require urgent treatment to avoid losing the tooth. Current first aid for these dental issues includes relieving pain, controlling bleeding, and seeking prompt dental care.