Perforation Repair in Wollongong

A perforation is an unintended communication between the inside of the tooth and the external periodontal tissues. It can occur during access cavity preparation, post space preparation, canal instrumentation, or as a complication of internal resorption. Managed promptly with the right materials and under appropriate magnification, most perforations can be sealed predictably and the tooth retained long-term.

Types of Perforation

Perforations are classified by location, and each location has different implications for prognosis and treatment:

• Pulp chamber floor perforation — through the floor of the pulp chamber into the furcation area of a multi-rooted tooth. Prognosis depends heavily on early sealing.
• Lateral root perforation — through the side wall of a root canal. Coronal-third perforations have the best prognosis; apical-third perforations are generally easier to seal through the canal.
• Strip perforation — a thinning of the canal wall from over-instrumentation, typically in the mesial roots of mandibular molars.
• Apical perforation — over-instrumentation through the apex. Usually manageable with careful apical obturation.
• Resorptive perforation — from internal or external cervical resorption that has breached the canal wall.

How Prognosis Depends on Three Factors

The long-term success of perforation repair is driven by:

1. Time to repair. The sooner a perforation is sealed, the less contamination reaches the periodontal tissues and the better the healing. Fresh, iatrogenic perforations sealed immediately have the strongest prognosis.
2. Size and location. Small perforations (under 1–2mm), in the coronal third, away from the crestal bone, are easier to seal and more predictable than large, deep, or subcrestal defects.
3. Material. Modern bioceramic materials — MTA (mineral trioxide aggregate), Biodentine and bioceramic putties — form a bond to dentine, seal hydrophilically in the presence of blood and tissue fluid, and promote healing of the surrounding periodontium. They are a major upgrade on the older amalgam, IRM or glass-ionomer repair materials.

How Perforation Repair Is Performed

At Wollongong Endodontics, repairs are performed under rubber dam with operating microscope magnification:

1. Diagnosis — the perforation is located precisely with CBCT where needed, and its size, location and relationship to surrounding bone documented.
2. Haemostasis and field control — bleeding from the perforation site is controlled with appropriate pressure and materials so the repair can be placed in a clean field.
3. Matrix placement — a resorbable matrix (collagen or calcium sulfate) is placed externally to support the repair material and prevent extrusion into the periodontal tissues.
4. Bioceramic placement — MTA or Biodentine is carefully placed into the perforation under microscope visualisation and condensed to a thin, well-adapted seal.
5. Completion — the root canal system is cleaned, shaped and obturated, the access restored, and the patient reviewed at 6 and 12 months to confirm periradicular healing.

When Surgical Repair Is Indicated

Most perforations are repaired from inside the tooth (orthograde). Where the perforation is inaccessible from the canal — often deep subcrestal lateral perforations or complex resorptive defects — a surgical approach can seal the defect from outside. Apical surgery techniques (flap, osseous access, bioceramic repair, suture) are used under the microscope. This is a specialist procedure with good outcomes when indicated.

Frequently Asked Questions