Evaluation of the effect of digital smile design combined with minimally invasive laser crown lengthening and its effect on Liébart smile line

doi:10.19439/j.sjos.2025.04.007

Abstract

Abstract: PURPOSE: To evaluate the effect of digital smile design combined with minimally invasive laser crown lengthening and the effect on Liébart smile line. METHODS: From January 2021 to May 2023, a total 108 patients receiving crown restoration treatment were selected and assigned to control group (n=54, receiving laser minimally invasive crown lengthening alone) and experimental group (n=54, receiving digital smile design in addition to the control group's treatment) using a random number table. Periodontal health indicators, restoration margin-related distance indicators, tooth mobility, Liébart smile line classification and aesthetic standard scores were compared between the two groups. RESULTS: Six months after treatment, the plaque index (PLI), probing depth (PD) and bleeding index (BI) of the experimental group were significantly lower than those of the control group. Additionally, the restoration margin to bone crest distance(RM-BC) and restoration margin to gingival margin distance (RM-GM) were significantly higher in the experimental group(P<0.05). Fourteen days after treatment, tooth mobility of the experimental group was significantly less than the control group (P<0.05). Six months after treatment, the Liébart smile line classification was superior in the experimental group (P<0.05);the pink esthetic score (PES) and white esthetic score (WES) of the experimental group were significantly higher than those of the control group(P<0.05). After one year of follow-up, there was no significant difference in the incidence of adverse events between the two groups(P>0.05). CONCLUSIONS: Digital smile design combined with minimally invasive laser crown lengthening can significantly improve the clinical efficacy and aesthetic effect of smile line in patients with crown restoration.

Key words: Crown lengthening, Minimally invasive laser, Digital smile design, Liébart smile line

CLC Number:

R783.3

Xu Ying, Liu Yuan. Evaluation of the effect of digital smile design combined with minimally invasive laser crown lengthening and its effect on Liébart smile line[J]. Shanghai Journal of Stomatology, 2025, 34(4): 382-386.

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