Radicular cyst

Disease Description (Causes and Symptoms)

• Name: Radicular cyst
• Causes and pathophysiology: When chronic inflammation develops around the root apex, mainly due to pulp necrosis (severe tooth decay or trauma), epithelial remnants within the periodontium and periodontal ligament (Malassez epithelial rests) proliferate in response to inflammatory stimulation and form a cystic lesion lined with epithelium (containing fluid or thin mucoid material). On radiographs, it often appears as a well-defined radiolucent lesion at the root apex.
• Main symptoms: Usually asymptomatic and discovered incidentally during radiographic examination. As the cyst enlarges, localized swelling, tenderness, tooth mobility, bone loss in adjacent tissues, and in some cases abscess formation with fever or an odontogenic fistula (drainage through the skin or oral cavity) may occur. Diagnosis is supported by oral examination, pulp vitality testing, and imaging examinations such as panoramic radiography, periapical radiography, or CBCT.

Treatment Methods (Standard Treatment, Medications, Procedures, Lifestyle Management, and Precautions)

• Conservative treatment:
  • Root canal treatment of the causative tooth (endodontic treatment, including root canal disinfection and filling) is the first-line treatment. Removing the source of inflammation through root canal treatment may cause the cyst to gradually decrease in size or disappear.
• Surgical treatment:
  • If there is no improvement with root canal treatment, or if the cyst is large and symptomatic, cyst removal (cystectomy/enucleation) and, if necessary, apicoectomy are performed.
  • If the tooth cannot be preserved or the infection is chronic and extensive, the lesion is removed after extraction.
• Medication:
  • In cases of acute infection (abscess, pain, or systemic symptoms), antibiotics (e.g., amoxicillin) and analgesic anti-inflammatory drugs may be administered for a short period. Antibiotics are used as an adjunct to surgical or endodontic treatment.
• Lifestyle management and precautions:
  • Before and after treatment, avoid excessive pressure from hard foods and protect the treatment area.
  • Root canal treatment may be performed over several visits, so avoid delaying appointments between treatments.
  • Maintain oral hygiene (toothbrushing and flossing) and undergo regular dental checkups.
• Risk of complications:
  • Extensive bone loss caused by continued cyst growth, damage to adjacent teeth, chronic recurrent infection, and, rarely, severe facial swelling or systemic infection. There is also a possibility of postoperative bleeding, infection, and nerve damage, depending on the location.

Outpatient Visit Checklist (Items to Bring and Symptom Records — Including Example Questions)

• Recommended items to bring:
  • A list of current medications (including prescription drugs, OTC drugs, and dietary supplements) and a history of allergies (especially drug allergies)
  • Previous dental records and recent radiographs (the originals or a CD/file, if possible)
  • A record of when the symptoms began and how they have progressed (when they started and changes in pain or swelling)
  • Notes on pain intensity (pain scale 0–10), presence of fever or enlarged lymph nodes, presence of drainage (pus or blood), and effects on eating or sleep
  • If there is facial or intraoral swelling, take photographs and bring them
• Examples of simple questions to prepare for the visit (for patients to prepare themselves):
  • "When did the symptoms begin?"
  • "Is the pain or swelling intermittent or persistent?"
  • "Have you recently received dental treatment (such as a filling or implant), or experienced trauma?"

Examples of General Questions to Ask the Doctor

• How long is the expected recovery period for this treatment (root canal treatment/cystectomy/extraction)?
• What are the side effects of the prescribed medications (antibiotics and painkillers), and what precautions should I take while taking them?
• Can this tooth be preserved, or does it need to be extracted?
• How likely is recurrence, and what additional treatment options are available if it recurs?
• When can I return to my usual routine in daily life (eating, exercising, and returning to work)?

Examples of Disease-Specific Questions

• Is it possible for the cyst to disappear completely with root canal treatment alone? If so, how long is this expected to take?
• What is the long-term prognosis of the tooth (possibility of preservation and recurrence rate) after cystectomy or apicoectomy?