Background and Objective: This study is a systemic review of coronally positioned flap, coronally positioned flap + chemical root surface conditioning, or coronally positioned flap + enamel matrix derivative (EMD) for the treatment of Miller class I and II gingival recession.Material and Methods: All studies available through the Medline database by the end of October 2005 were used. Each study provided mean clinical attachment level, keratinized tissue, probing pocket depth, gingival recession depth and root coverage percentage before and after treatment with coronally positioned flap alone, coronally positioned flap + chemical root surface conditioning , or coronally positioned flap + EMD. Effectiveness was evaluated by comparing the weighted mean average in gingival recession depth, probing pocket depth, clinical attachment level, keratinized tissue and root coverage percentage achieved with the three treatments.Results: Seven studies for the coronally positioned flap + EMD group, four studies for the coronally positioned flap + chemical root surface conditioning group, and seven studies for the coronally positioned flap group were retrieved for this weighted mean analysis. The results of clinical attachment level, gingival recession depth, and root coverage percentage in the coronally positioned flap + EMD group were statistically significantly better than the changes in the coronally positioned flap and coronally positioned flap + chemical root surface conditioning group at 6 and 12 mo (p < 0.001). There was no significant difference at the 6-mo comparison among clinical attachment level, keratinized tissue, probing pocket depth, and gingival recession depth, except in the root coverage percentage for coronally positioned flap and coronally positioned flap + chemical root surface conditioning groups.Conclusion: The results suggest that root coverage by the coronally positioned flap and coronally positioned flap + chemical root surface conditioning procedures were unpredictable but became more predictable when the coronally positioned flap procedure was improved by the modification of adding EMD.

The relationship between radiographic measures of severity of osteoarthritis (OA) and changes in gene expression in joints are not well characterised. In this study, the expression of 11 candidate genes was characterised by quantitative reverse transcriptase polymerase chain reaction in normal and OA cartilage and bone from the elbows of dogs with fragmented coronoid disease. The levels of expression of type I collagen α2 chain (COL1A2), type III collagen α1 chain (COL3A1), lumican (LUM), matrix metalloproteinase-2 (MMP2), -9 (MMP9) and -13 (MMP13) genes were increased and the expression of tissue inhibitor of metalloproteinase-2 (TIMP2) and cathepsin D (CTSD) genes were decreased in OA cartilage relative to normal cartilage. All differences correlated with radiographic measures of severity of OA. Levels of expression of COL1A2, MMP2, MMP9, MMP13 and TIMP1 were increased, whereas expression of TIMP2 was decreased in OA bone relative to normal bone. Cartilage gene expression may be correlated with the radiographic severity of OA.