CARBON-DIOXIDE LASER FOR DEEPITHELIALIZATION OF PERIODONTAL FLAPS

REGENERATION OF MINERALIZED AND SOFT connective tissue components of t he attachment apparatus is the main goal in the treatment of periodont al diseases. Often, apical migration of epithelium (long junctional ep ithelium) effectively prevents the formation of bone and connective ti ssue attachment after periodontal surgery. The purpose of the present study was to compare conventional periodontal surgery combined with ca rbon dioxide laser and conventional periodontal surgery alone with res pect to epithelial elimination and degree of necrosis of mucoperiostea l flaps. After signing a consent form, five patients with at least two comparable bilateral periodontal defects needing pocket elimination s urgery participated in this study. The investigators randomly divided each side into test and control sites. Each patient received oral hygi ene instruction and initial therapy prior to surgery. At surgery, the test site received a sulcular incision and carbon dioxide laser de-epi therialization of the outer and inner aspects of the flap. The control group received reverse bevel incision only. The surgeon performed ope n flap debridement on all teeth. At the time of surgery, the surgeon d id a biopsy of each site and submitted specimens for histologic evalua tion. A matched pairs t-test was used to analyze the data. The results show significant differences between the carbon dioxide laser and rev erse bevel incision with respect to sulcular (P less than or equal to 0.025) and gingival (external) (P less than or equal to 0.01) flap sur face epithelial elimination and tissue necrosis (P less than or equal to 0.005). These results should be replicated with a larger number of subjects. The carbon dioxide laser eliminated sulcular and gingival (e xternal) epithelium without disturbing underlying connective tissue. T his finding supports the concept that the carbon dioxide wavelength ha s little or no effect on tissues beyond the target. However, neither l aser nor blade eliminated all the epithelium. Researchers observed chr onic inflammation in the control and test sites, with a predominance o f plasma cells. Lining the sulcular and gingival (external) lased area s, investigators found coagulation necrosis covered by fibrin and coag ulated blood. The laser appears to effectively remove epithelium at th e time of surgery; however, future long-term, well-controlled quantita tive histologic studies are needed to evaluate the effect of repeated carbon dioxide laser de-epithelialization of the gingival (external) s urface of mucoperiosteal flaps at intervals during the healing period.