What complications can arise when leaving a root behind after partial extraction of lower molar tooth?

Leaving a root behind after partial extraction of a lower molar tooth can lead to several complications, including:

1. Infection: The remaining root can become infected, leading to pain, swelling, and discomfort in the affected area. The infection can spread to the surrounding bone and tissues, causing further complications.

2. Pain: The retained root can cause persistent pain and discomfort in the area. The pain may be sharp, throbbing, or aching, and can worsen when biting or chewing.

3. Abscess formation: An abscess is a localized collection of pus that can form around the retained root. Abscesses can cause severe pain, swelling, and difficulty opening the mouth.

4. Damage to surrounding structures: The retained root can damage the surrounding teeth, bone, and soft tissues. It can lead to erosion of the jawbone, damage to the nerves, and sinus problems.

5. Delayed healing: The presence of a retained root can delay the healing process after the partial extraction. The wound may remain open and may not heal properly, increasing the risk of infection.

6. Difficulty with future treatments: Retained roots can make it more challenging to perform future dental treatments, such as placing dental implants or dentures, in the affected area.

To avoid these complications, it's essential to ensure the complete removal of all root fragments during tooth extraction. If a root is accidentally left behind, prompt intervention and treatment by a dentist or oral surgeon are necessary to address the issue and prevent further complications.