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One- Versus Two-Stage Aesthetic Crown Lengthening

One- Versus Two-Stage Aesthetic Crown Lengthening for Restorative Purposes: A Randomized Controlled Trial.

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04409366
Enrollment
30
Registered
2020-06-01
Start date
2013-04-01
Completion date
2018-10-01
Last updated
2020-06-01

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Patients in Need of Surgical CL in the Anterior Maxillary Sextant for Restorative Purposes

Brief summary

This randomized controlled trial was aimed at assessing the efficacy of a two-stage crown lengthening intervention (SCL) for restorative purposes in the aesthetic zone compared with a one-stage crown lengthening procedure (CCL).

Detailed description

Subjects were randomly allocated to receive SCL or CCL. SCL consisted of full thickness flaps followed by bone recontouring and minor gingivectomy 4 months postoperatively, if required. In CCL, osseous recontouring after sub-marginal incisions was performed, followed by flap repositioning. Records were obtained at baseline, 4 months (only in SCL), 6 and 12 months. Primary outcome was the precision in achieving a predetermined gingival margin position. Other outcomes were changes in the gingival margin position and keratinized tissue width (KTW) at 12 months, and patient-reported outcomes (PROMs) using the OHIP-14 tool.

Interventions

OTHERConventional Crown Lengthening (CCL)

Using the surgical guide, submarginal internal bevel incisions were performed on the buccal aspect of the affected teeth. A full-thickness flap was raised up to the mucogingival junction (Dominguez et al., 2020). Ostectomy and osteoplasty were carried out by means of rotatory instruments and surgical chisels, as necessary, to achieve the necessary space between the bone crest and the restorative margin according to the presurgical plan. The CEJ was not the reference point since, in many cases, the position of the final margin of the restoration was planned apical to the actual position of the CEJ. Exposed root surfaces were carefully instrumented manually with curettes and, finally, vertical internal mattress sutures were placed to position the gingival margin at the level of the margin of the planned restoration. Sutures were removed after 7 days

OTHERTwo-stage Crown Lengthening (SCL)

In the first surgical intervention, intrasulcular incisions were performed and a full thickness flap was raised up to the mucogingival junction. Ostectomy and osteoplasty were performed to establish the space for supracrestal tissue attachment, following the restorative plan and using the presurgical blueprint as the reference to determine the final position of the restoration margin, instead of the CEJ (Lee, 2004). Then the flaps were repositioned and secured with internal mattress sutures, placing the gingival margin at the original level. Sutures were removed at 7 days. In the second stage, after 3-4 months, minor gingival recontouring was performed, if necessary, to attain the desired gingival margin position according to the presurgical plan.

Sponsors

Universidad Complutense de Madrid
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

* older than eighteen years of age; * more than 20 teeth in the mouth; * with full mouth plaque and bleeding scores lower than 15%; and * without probing pocket depth and/or attachment loss \>4 mm

Exclusion criteria

* Pregnant women or breastfeeding * smokers * treated with antimicrobial and/or anti-inflammatory drugs within two months prior to entering the study * currently undergoing orthodontic therapy

Design outcomes

Primary

MeasureTime frameDescription
T1-T4Baseline-12 monthsThe difference in mm between the ideal gingival margin (T1) and the position of the gingival margin at 12 months (T4).

Secondary

MeasureTime frameDescription
Clinical Crown LengthAt baseline, 6- and 12-monthDistance from the gingival margin to the incisal edge on the midbuccal.Measured in mm.
Amount of keratinized tissueAt baseline, 6- and 12-monthDistance from the gingival margin to the mucogingival junction on the midbuccal.Measured in mm.
Gingival display upon smilingAt baseline, 6- and 12-monthDistance from the gingival margin of the central incisors to the lower edge of the upper lip. Measured in mm.
Supracrestal tissue dimensionAt baseline, 6- and 12-monthDistance from the gingival margin to the alveolar bone crest (GM-ABC) as determined by bone sounding following local anesthesia. Measured in mm.

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026