Root perforation is an artificial communication between the root canal system to the supporting tissues of teeth or to the oral cavity. (AAE Glossary)
Accidental root perforations, which may have serious implications, occur in approximately 2–12% of endodontically treated teeth, according to Ingle, Kerekes, Seltzer and many other authors.
Causes of Perforations
Misaligned use of rotary burs during endodontic access preparation and search for root canal orifices.
Negotiating calcified and curved canals
Lateral extension of the canal preparation (to a so-called strip perforation)
Inappropriate post space preparation
Signs and Symptoms of Perforations
Sudden bleeding and pain during instrumentation of root canals or post preparations in teeth are warning signals of a potential root perforation.
Suppurations resulting in tender teeth, abscesses, and sinus tract including bone resorptive processes may occur.
Down-growth of gingival epithelium to the perforation site.
Detection of root perforations
Sudden bleeding from canal (Paper points are useful aids)
Radiopaque instruments going to the periodontal tissues, confirmed with radiographs or CBCT
Use of electronic apex locator
Use of operating microscope for additional illumination and magnification
A narrow isolated deep pocket (in long standing root perforations)
Sequels of root perforation
Bacterial infection emanating either from the root canal or the periodontal tissues, or both, prevents healing.
Once an infectious process has established itself at the perforation site, prognosis for treatment is precarious and the complication may prompt extraction of the affected tooth.
Measures for Prevention
Before accessing canals
Check crown-root alignment
Careful examination of radiograph
Shape and depth of pulp chamber
Width of furcation floor
Before root canal preparation
Use of magnification
Avoid rubber dam before access in teeth with
Narrow or calcified pulp chambers
Crowned teeth
Pulp chamber is centrally located at the level of CEJ.
During Root canal Preparation
Avoid overzealous preparation
Use flexible instruments with copious irrigation and lubrication
During Post Space Preparation
Avoid excessive pressure with post drills, GG or Peeso reamers
Stop when gutta-percha is not coming out from the canal and verify with magnification to see if you are going to the right direction.
Factors of Significance on Prognosis of the Treatment
Time from the perforation to detection
Size and shape of the perforation
Location
Repair material
Over extrusion of repair material
Preoperative radiolucency adjacent to perforation site
Ideal material properties for root perforation repair
Biocompatible
Easy manipulation
Hy hillic
Fast setting
Insoluble
Antimicrobial activity
Smooth surface
Adequate sealing
No discoloration
Radiopaque
Materials in the market for root perforation repair
Amalgam
Composite resin
Resin modified glass ionomer
Cavit
Super EBA
Zinc Oxide Eugenol / IRM
MTA and other calcium silicate based materials
Treatment modalities
Apical level / Mid-root level
Nonsurgical approach and repair with calcium silicate base material.
Monitor for signs or symptoms.
Surgical approach when a periapical lesion develops after monitoring period.
Prognosis: Fair-Good
Crestal / Furcal level
Orthodontic extrusion or surgical crown lengthening procedure have been recommended for single-rooted teeth to bring the perforation to a coronal position.
Nonsurgical approach and repair with composite resin, resin modified glass ionomer or fast set calcium silicate base material in scenarios where the material is not constantly challenged by saliva.
Prognosis: Poor-Fair.
