Laser de-epithelialization for enhanced guided tissue regeneration. A paradigm shift?

Abstract

The rationale for laser de-epithelialization stems from the attempts to block the down-growth of epithelium into the healing periodontal wound after surgery and prevent formation of a long junctional epithelial attachment. This concept has seen numerous techniques for accomplishing the blockage of epithelium. The advent of GTR was an offshoot of this concept and led Gottlow et al [table: see text] to examine the effects of selectively blocking certain cell types from contacting the root surface during periodontal wound healing. The use of a CO2 laser to de-epithelialize the gingival flaps is an attempt to exclude this cell type from the healing wound and has been used with and without the benefit of GTR membranes. In a study on beagle dogs, the histologic results of using membranes and the laser procedure enhanced the wound healing and regeneration of new bone, cementum, and connective tissue attachment when compared with paired defects using the membranes alone. The results from the human studies and case reports combined with the animal studies indicate a positive benefit in wound healing because of the laser de-epithelialization technique. The use of an osseous graft in treatment of periodontal defects has been shown to stimulate new bone growth effectively and to regenerate new attachment. It has been speculated that the additional benefit of an osseous graft in GTR procedures is the organization of the blood clot at initial healing, which may tend to maintain the space needed for regeneration and to provide a matrix for the fibrin clot to retard epithelial down-growth. Studies comparing the results of osseous grafting with flap debridement always have shown that the amount of new bone formation and clinical new attachment favor the grafted sites versus paired nongrafted sites. The effects of removal of the pocket epithelium at the time of periodontal surgery have been studied by several authors, and these studies generally shown an incomplete removal of the sulcular epithelium by the inverse bevel incision. Epithelial excision was studied by Centty et al, who compared the removal of sulcular epithelium by the CO2 laser technique with conventional methods. Their results confirm that (1) a more complete removal of sulcular epithelium was obtained by laser than by knives, and (2) the technique effectively removes the oral and sulcular epithelium from a gingival flap without damaging the viability of the flap during wound healing. The technique as described in this article was used by Israel et al to verify further the ability to maintain a viable gingival flap during multiple laser deepithelialization procedures in humans during the first 30 days of healing. [table: see text] The concept of laser de-epithelialization as an adjunct to regenerative periodontal procedures currently is being studied in a multicenter university setting using a parallel study in controlled clinical trials. The first of these reports was mentioned previously (Araujo et al, unpublished data) and shows the enhanced wound healing of periodontal defects through use of the laser de-epithelialization technique. The authors believe that this technique has shown significantly better results than those obtained through conventional osseous grafting alone and appears to be comparable to the results reported for GTR procedures with barrier membranes. This concept provides a paradigm shift from the conventional use of GTR therapy by acknowledging the difficulty in controlling epithelium during the early wound healing. It also allows a more comprehensive therapy for treating periodontal disease that addresses the generalized nature of the disease, with multiple lesions being treated concurrently in an economical manner. The patient presenting with generalized advanced periodontal disease could have several defects definitively treated in one quadrant using the laser deepithelialization technique without the need for multiple membrane therapy. (ABSTRACT TRUNCATE