Apicoectomy - A Detailed Step-by-Step Guide

What is an Apicoectomy?

Indications

• Persistent periapical pathology despite adequate orthograde root canal treatment
• Inaccessible root canal (e.g., blocked by a post, screw, or calcification)
• Root canal overfill with extruded material causing symptoms
• Suspected lateral or accessory canals not treated by orthograde approach
• Need for biopsy of periapical lesion
• Root resorption at the apex

Contraindications

• Vertical root fracture extending into the crown
• Insufficient remaining root length after resection
• Severe periodontal disease (poor bone support)
• Non-restorable tooth (extensive decay)
• Proximity to vital structures (inferior alveolar nerve, maxillary sinus) - requires careful planning

Pre-Operative Phase

Step 1 - Pre-operative Assessment and Imaging

• Review clinical history, symptoms, and prior endodontic treatment records
• Take periapical radiographs (paralleling technique) to evaluate:
  • Root length and curvature
  • Proximity to anatomical structures (mental foramen, maxillary sinus, inferior alveolar canal)
  • Size and extent of periapical lesion
  • Post/screw presence
• Cone-beam CT (CBCT) is now strongly recommended - it provides 3D visualization of root anatomy, bone thickness, and precise lesion location, enabling better surgical planning
• Assess patient's medical history: bleeding disorders, anticoagulants, bisphosphonate therapy (risk of MRONJ), immunosuppression, uncontrolled diabetes
• Informed consent

Step 2 - Pre-operative Preparation

• Antimicrobials: Prescribe antibiotics if indicated (e.g., amoxicillin 500 mg TID, 3 days pre-op in high-risk patients)
• NSAIDs: Pre-operative ibuprofen (600-800 mg) 1 hour before surgery reduces post-op pain and swelling
• Chlorhexidine mouthrinse (0.12%) pre-operatively to reduce oral bacterial load
• Patient is positioned supine or semi-supine

Operative Steps

Step 3 - Local Anesthesia

• Administer local anesthetic with vasoconstrictor (typically lidocaine 2% with 1:100,000 epinephrine)
• Injections given as:
  • Labial/buccal infiltration near the apex
  • Palatal/lingual infiltration if needed
  • Regional nerve block if posterior teeth (inferior alveolar block for mandibular molars)
• The vasoconstrictor (epinephrine) is critical - it provides hemostasis and a bloodless surgical field, improving visibility
• Allow 5-10 minutes for full anesthetic effect and vasoconstriction

Step 4 - Flap Design and Incision

• Use a no. 15 or 15c scalpel blade
• Full-thickness incision down to bone in a single stroke
• Vertical releasing incisions placed at line angles of teeth (never over the root prominence)
• Incision placed on healthy bone - never over the lesion
• Horizontal cut placed in the gingival sulcus (intrasulcular) or 2-3 mm apical to it (submarginal)

Step 5 - Flap Elevation (Mucoperiosteal Reflection)

• Elevate the full-thickness mucoperiosteal flap using a periosteal elevator (e.g., Molt no. 9 or Prichard elevator)
• Begin at the vertical releasing incision and move anteriorly/posteriorly
• Keep the elevator in firm contact with bone to avoid tearing the periosteum
• Retract the flap with a Minnesota retractor or Seldin retractor, keeping the retractor resting on bone (not soft tissue) to prevent ischemia
• The full extent of the lesion and root apex must be visible before proceeding

Step 6 - Osteotomy (Bone Removal)

• If cortical bone has already been perforated by the lesion, the root tip may already be visible; if not, create a bone window
• Use a round surgical carbide bur (e.g., no. 6 or 8) in a high-speed handpiece with continuous saline irrigation to prevent thermal bone necrosis
• Begin the osteotomy at the anticipated location of the root apex (guided by pre-op imaging and root length measurements)
• Microsurgical principle: Keep the osteotomy as small as possible - just large enough to access the root end and perform the subsequent steps
• Remove bone carefully until the root tip and periapical tissue are identified
• Hemostasis: apply epinephrine-soaked cotton pellets or bone wax into the crypt to control bleeding from cancellous bone

Step 7 - Periapical Curettage

• Use a curette (e.g., Lucas curette, Miller curette, Molt curette)
• Strip the tissue from its bone attachment with the concave surface of the curette facing bone
• Once free, remove tissue with the convex surface facing bone
• Work systematically around the entire lesion
• Collect the tissue in formalin (10% neutral buffered formalin) for histopathologic examination - this is important because:
  • Granuloma and cyst may look identical clinically
  • Rare malignancies can present as periapical lesions
  • Biopsy provides definitive diagnosis
• If granulation tissue is adherent to the lingual root surface, widen the osseous window slightly
• If the lesion has perforated the lingual plate, use Allison forceps or a scalpel blade to complete tissue removal

Step 8 - Root-End Resection (Apicoectomy Proper)

• Standard: 3 mm from the apex - removes the apical delta (complex network of accessory canals), 93% of lateral canals, and the most contaminated portion of the root
• In re-surgery cases or when a post is present near the apex, a smaller resection (1-2 mm) may be necessary
• Leave at least 7-8 mm of root to maintain periodontal support

• The resection plane should be perpendicular (0-10 degrees) to the long axis of the root - this is a key advance of microsurgery over the traditional technique
• The old technique used a steep 45-degree bevel for visibility, but this:
  • Exposes far more dentinal tubules (up to 4x more)
  • Increases risk of missing lingual canals
  • Creates a larger seal requirement
• A nearly perpendicular cut at 0-10 degrees minimizes tubule exposure and leakage

• Use a 45-degree angled surgical handpiece (contra-angle)
• Use Lindemann burs (H162 bone-cutting bur) or surgical tapered fissure burs with saline irrigation
• Cut with a smooth, controlled motion
• Perform at mid-range magnification (approximately x10 under the surgical microscope)
• Inspect the resected root face immediately under high magnification

Step 9 - Inspection of the Resected Root Face

• Apply methylene blue stain to the resected root face - this stains the PDL, cracks, and canal anatomy, making them visible
• Identify:
  • Main root canal(s) and their fill
  • Isthmuses (connecting tissue between two canals in the same root - a critical structure for surgical success)
  • Accessory/lateral canals
  • Dentinal cracks or fractures (if severe, extraction may be unavoidable)
  • Gaps between existing root fill and canal wall
  • Unfilled portions of the root canal system
• All identified structures must be included in the subsequent root-end preparation

Step 10 - Root-End Preparation (Retroprepation)

• Small round bur or inverted cone bur in an angled micro-handpiece
• Problematic - difficult to control direction and depth; often led to lateral perforations

• Use an ultrasonic unit with dedicated microsurgical retrotips (e.g., CT tips, diamond-coated retrotips)
• The retrotips are small, angled (70-90 degrees), and can be directed along the root canal axis without the need for a steep bevel
• Create a cavity exactly 3 mm deep, with walls parallel to and within the anatomic outline of the root canal space
• Must include any isthmus, accessory canal, or unfilled portion identified in Step 9
• Irrigate with saline throughout
• Dry the cavity with micro-sponges or paper points
• Re-inspect under magnification to confirm cavity walls are clean and crack-free

Step 11 - Root-End Filling (Retrofilling)

• Apply the filling material with a micro-carrier (e.g., MAP system for MTA, small amalgam carrier)
• Condense with micro-pluggers
• Remove excess material from the cavity margins with micro-excavators
• Inspect the final fill under magnification - the material must be flush with the resected root face with no voids
• Take a radiograph to verify the fill if needed

Step 12 - Hemostasis and Wound Preparation Before Closure

• Irrigate the surgical site with sterile saline
• Remove any blood clots, bone particles, or debris from the bony crypt
• Allow a clean blood clot to form in the crypt (this is needed for healing)
• Bone grafting: In cases of large osseous defects (through-and-through defects), place a bone graft material (e.g., demineralized freeze-dried bone allograft, beta-TCP) with or without a barrier membrane (guided tissue regeneration - GTR) - recent 2025 systematic reviews support this approach for large defects
• Apply a collagen hemostatic agent if needed (Collaplug, Gelfoam)

Step 13 - Flap Repositioning and Suturing

• Reposition the mucoperiosteal flap carefully to its original position
• Ensure:
  • No tension on the flap margins
  • Vertical releasing incisions are re-approximated precisely
  • Papillae are properly seated interproximally
• Suture materials:
  • Resorbable: Vicryl (polyglactin) 4-0 or 5-0 - dissolves in 7-10 days (commonly preferred now)
  • Non-resorbable: Silk 3-0 or 4-0, or nylon (removed at 48-72 hours or 7 days)
• Suture technique:
  • Simple interrupted sutures at vertical releasing incision lines
  • Sling or mattress sutures may be used at horizontal portions
  • Goal is passive, tension-free adaptation of flap margins to bone
• Apply gentle pressure with moist gauze for 2-3 minutes

Post-Operative Phase

Step 14 - Immediate Post-op Instructions

• Ice pack application: 20 min on / 20 min off for the first 24-48 hours (reduces swelling and pain)
• Soft diet for 7 days (avoid hard, crunchy foods)
• No smoking or alcohol (impairs healing)
• No rinsing vigorously for 24 hours
• Gentle chlorhexidine rinse (0.12%) starting 24 hours post-op, twice daily
• Keep head elevated (reduces swelling)
• No strenuous physical activity for 3-5 days

Step 15 - Medications

• Analgesics: Ibuprofen 400-600 mg every 6-8 hours (or combination with acetaminophen) for 3-5 days
• Antibiotics: If indicated (amoxicillin 500 mg TID x 5-7 days, or metronidazole + amoxicillin for persistent infections)
• Corticosteroids: Dexamethasone 4-8 mg pre-op or intra-op reduces post-op swelling significantly

Step 16 - Follow-up and Suture Removal

• Suture removal (if non-resorbable): 48-72 hours for silk sutures, or 7 days
• Radiographic follow-up: at 6 months and 1 year
• Clinical and radiographic success is assessed by:
  • Resolution of symptoms
  • Bone healing on radiograph (periapical lesion decreasing/resolving)
  • Absence of fistula or swelling

Key Principles of Modern Microsurgical Apicoectomy (vs. Traditional)

Success Factors and Prognosis

• Absence of preoperative symptoms
• Small periapical lesion
• Good orthograde root filling
• Microsurgical technique with proper root-end filling
• Good periodontal status
• Non-smoker

• Large cystic lesion
• Posterior teeth (technical difficulty)
• Curved or short roots
• Previously failed periapical surgery (re-do apicoectomy)

• von Arx T. "Apical surgery: A review of current techniques and outcome." PMC3770245
• Kim S, Kratchman S. "Modern endodontic surgery concepts and practice: a review." J Endod. 2006 [PMID: 16793466]
• Duan X, Mickel AK. "Practical Steps in Endodontic Surgery." Case Western Reserve University School of Dental Medicine
• Barnaba et al. "The Use of Bioceramics in Retrograde Apicectomy." Aust Endod J. 2025 [PMID: 40464307]
• Sabeti et al. "Optimizing Endodontic Surgery: Guided Tissue Regeneration, Grafting, and Platelet Concentrates." Dent J. 2025 [PMID: 40136719]