Evaluation of healing with use of an internal matrix to repair furcation perforations


  • To evaluate healing responses following repair of furcation perforations, with and without an internal matrix and to evaluate the efficacy of 2 matrix materials


  • N= 80 teeth (2 Premolars + 3 molars per quadrant in 4 baboons)
  • Internal matrix materials: HAPSET (65 % non-resorbable hydroxyapatite, 35 % plaster of paris) and hydroxyapatite (HA). If repaired, amalgam was the repair material.
  • Following furcation perforations (rubber dam isolation), teeth randomly assigned into 5 groups : HAPSET + Amalgam , HA + Amalgam, no matrix + Amalgam, Positive control- no repair, and Negative control- No perforation
  • Animals sacrificed for histologic examination at 1 week and 1, 3, and 7 months


  1. Positive controls and no matrix + amalgam groups showed severe inflammation for the duration of the study
  2. Using a matrix prevents extrusion of the amalgam thus decreasing severity and duration of the inflammatory response
  3. There is no difference in tissue response to HAPSET and HA. Both materials underwent initial connective tissue encapsulation followed by directly contacting bone deposition (no intervening connective tissue)

Clinical Significance:

When performing non-surgical furcation perforation repair, use of an internal matrix material will limit repair material extrusion, which reduces long-term inflammation. No difference between HAPSET and HA in terms of duration of inflammation and both promoted bone deposition directly contacting the repair material

Nonsurgical repair of perforation defects


  • Describe the use and limitations of internal matrix for non-surgical perforation repair


  • N= 16 articles (from 1971- 1986) reviewed and summarized


  • An internal matrix will help control repair material from extruding (most common reason for failure) and aid in hemostasis (increasing the repair material’s sealing ability)
  • Large differences in the success of repair materials have been reported in the literature and may be due to operator skill with the various repair materials
  • Use of an internal matrix:
    • may be utilized in accessible, visible locations, such as the furcation and in coronal and middle thirds of straight canals
    • is contraindicated in strip perforations and when perforation is coronal to the crestal bone
  • Major limitations of non-surgical perforation repair include visibility (extent and location of defect), accessibility (within the narrow confines of the canal space), and maintaining patency of the canal while manipulating matrix and repair materials

Clinical Significance:

Perforations in visible, accessible locations may be repaired with the aid of an internal matrix to  increase prognosis by reducing hemorrhage and contamination affecting the repair material and preventing extrusion of the repair material

Recall Evaluation of Iatrogenic Root Perforations Repaired With Amalgam and Gutta-Percha


Examine factors affecting healing of root perforations with amalgam or gutta percha (GP).


-57 cases of iatrogenic root perforations obtained from student clinics at the University of Oklahoma College of Dentistry.

-Perforations repaired with amalgam (24) or GP (33).

-5 failing cases were treated surgically.

– recalls at 3 months – 6 years


-GP had 57.6% failure, 73% of all failures.

-Amalgam had a 26% failure rate.

-70% of all failures involved extrusions, and 83% of this were GP repairs.

-Success was greater than failure even when repair delayed up to 60 days.

-Amalgam was superior to GP.

-Repairs with extruded GP most likely to fail.

-All surgical cases showed healing after treatment

Clinical Significance:

Amalgam is better than GP WVC (due to extrusion as a cause of failure.)  A delay in repair did not affect outcome.  Surgical repair appears to be highly successful.

An evaluation of the use of amalgam, Cavit, and calcium hydroxide in the repair of furcation perforations



N=4 dogs with healthy periodontium.

-maxillary and mandibular premolar/molars; 64 perforations made.

-Performed under general anesthesia, rubber dam placed and accesses made, Cleaned and shaped with sterile saline and obturated with Cavit.

-#4 round bur used to perforate the furcation which was then rinsed with sterile saline. Heme controlled with racellets.

-4 equal groups of perforation repair materials used: amalgam, cavit, CaOH, and nothing (cotton pellet).

-occlusal amalgams placed and 3 month observation occurred clinically and xray; sacrificed dogs and histo



-possible role of bacterial contamination not investigated.

-tissue responds best in the following order:  amalgam>cavit>CaOH>nothing.

-most bone resorption and clinical exposure of furcal areas occurs within first 1-2 months and then slows.

-cavit and amalgam had a similar inflammatory response, much less than CaOH.

Clinical Significance:

Attempting to repair a perforation better than no repair.  The use of CAOH for 1 month or more results in more periodontal destruction.  Amalgam is better than Cavit for repairs.

Nonsurgical therapy for the perforative defect of internal resorption


This paper suggests using the technique for pulpless divergent teeth be applied to internal resorptive defects.


-teeth were accessed, cleaned and shaped, and interim treatments of CAOH used for 4-6 week intervals.

-when a  dry canal obtained and any sinus tracts healed, the canals were obturated under pressure using cold lateral and sealer.


-3 case reports using treatment resulted in healing:

  • Case 1: Lateral incisor with resorptive defect and sinus tract of at least a year. CAOH used for 5 weeks and tooth obturated.  Healing at 1 year recall.
  • Case 2: Maxillary canine with apical resorptive defect and sinus tract. Resorption was of possible orthodontic origin.  CAOH placed and evaluated for 1 year.  Mineralization of defect occurred and tooth obturated.
  • Case 3 : Pulpotomy 4 years prior with crown placement. There was a palpable fluctuant swelling , periapical radiolucency mesial and resorptive defect distally.   Canals were cleaned and shaped, treated with 6 weeks of CAOH, and then obturated.  Clinical signs disappeared and internal resorptive defect noted mesially after obturation.  At 18 month recall tooth showed periapical healing.

Clinical Significance:

2-6 weeks of CAOH prior to obturation resulted in healing of teeth with suppuration and internal resorption.

Periodontal Tissue Reactions After Surgical treatment of Root Perforations in Dog’s Teeth A Histological Study


Examine root perforation healing


-2 dogs, md premolars and molars.

-16 root perfs made under GA.

-RD, crowns burred to pulp, C+S, obturated with GP.

-4 equal groups:

-A1: teeth perfed with bur with immediate sx repair with GP.

-A2: same as above but repair with amalgam.

-B1: teeth perfed with bur, filled with interim phosphate cement. Waited 1.5-7.5 mo, then

repaired with GP.

-B2: same as above but with amalgam as final repair material.

-experiments made in adjacent root pairs (A1-A2, B1-B2).

-followed via xray over time and dogs sacrificed and histo exam completed.


-all cases showed at least mild chronic inflammation.

-amalgam caused more pronounced inflammation vs. GP.

-formation of new bone seen in all cases, but GP had increased amounts.

-GP had more CT capsule reaction vs. amalgam.

-in group B results, extensive bone resorption seen during time perforation site left with interim phosphate cement.

Clinical Significance:

Immediate root perforation repair had better healing and decreased perio destruction.