No universal dimension of the biologic width appears to exist .
BACKGROUND Consideration of the biologic width in restorative dentistry seems to be important for maintaining periodontal health .
OBJECTIVE To evaluate the dimensions of the biologic width in humans .
Clinical evaluation of the supraosseous gingivae before and after crown lengthening.
BACKGROUND Despite the broad use of  crown-lengthening surgery ( CLS )  , there is no complete agreement as to the desired amount of exposed sound tooth structure needed to accommo date both the restorative needs and the reformation of the supraosseous gingiva ( SOG ) . Classically , it has been proposed that approximately 3 mm of SOG , the amount considered by most to be present before surgery , will be reformed after CLS . The purpose of this study was to test the viability of transsulcular probing ( TSP )  and to determine whether the SOG that forms after CLS is the same as that measured preoperatively . METHODS Nineteen patients underwent CLS with the surgical tooth acting both as the control and the test site . The SOG dimension was measured by TSP before and 6 months after surgery . Stents were used as fixed reference points . Intraclass correlations were calculated to test for the reliability of TSP measurements versus direct-bone-level ( DBL ) measurements . A Wilcoxon signed-rank test was used to compare the means for the mean buccal , mean lingual , and overall mean SOG dimensions at baseline to corresponding measurements at 6 months . RESULTS Intraclass correlation coefficients for TSP measures of SOG to DBL measures of SOG ranged from 83.4 % agreement to 91.9 % agreement , with all correlations being highly significant ( P < 0.001 ) , indicating a high degree of agreement between TSP and DBL . The differences in SOG dimensions , 6 months after surgery compared to baseline , were as follows : mean buccal , 0.51 mm ; mean lingual/palatal , 0.61 mm ; overall mean , 0.56 mm . These differences were significant for all three comparisons ( P < 0.001 , P < 0.004 , and P < 0.001 , respectively ) . CONCLUSIONS TSP is an accurate alternative method to DBL in clinical ly determining SOG dimensions . Six months after CLS , the SOG dimension was reduced by 0.51 to 0.61 mm compared to the presurgical measurement , with these mean differences being statistically significant
No universal dimension of the biologic width appears to exist .
BACKGROUND Consideration of the biologic width in restorative dentistry seems to be important for maintaining periodontal health .
OBJECTIVE To evaluate the dimensions of the biologic width in humans .