Tooth pain cause, why tooth decay happens even after brushing teeth regularly? Tooth pain happens due to tooth decay or gums issues or due to accident mostly.Tooth issues are result of poor oral hygiene.Brushing teeth is not enough.You also need to clean interdental areas with dental floss, tongue cleaning is essential, water intake is very important.Preventive dental care is essential. To know more book your appointment with dr Prashant bhangale, dentist