evaluation of dimensional changes of supraosseous gingiva following crown lengthening

background and aims. clinical studies on dimensional changes of supraosseous gingiva (sog) following crown lengthening surgery have yielded different results. the aim of the present study was to evaluate the alterations in sog dimension following crown lengthening surgery. materials and methods. this clinical study included 20 patients with 20 teeth needing surgical exposure for proper restorative treatment. clinical parameters, including gi, pd, sog, kg (keratinized gingiva) and bl (bone level) were recorded at baseline and two months after treatment. surgical crown lengthening procedures were carried out on all the teeth. after a two-month period of healing, the parameters were measured again. results. the amount of kg at the baseline and two months after treatment were 5.00 ± 0.85 and 4.15 ± 0.9 mm, respectively (p = 0.001). the fgm at baseline, immediately after suturing, and two months later were 4.07 ± 1.36 mm, 5.46 ± 1.15 mm and 5.16 ± 1.1 mm, respectively (p = 0.004). the mean bone reduction was 1.69 ± 0.52 mm. the mean sog at interproximal site at baseline and two months after surgery were 3.87 ± 0.7 mm and 3.22 ± 0.5 mm, respectively (p = 0.001). the mean tissue re-growth at interproximal sites was 2.2 ± 0.5 mm. conclusion. following surgical crown lengthening, vertical dimension of sog significantly decreased within two months after treatment. tps is a reliable and accurate technique for measuring the apico-coronal dimension of sog.