J Dent Rehabil Appl Sci.  2021 Sep;37(3):130-137. 10.14368/jdras.2021.37.3.130.

3D analysis of soft tissue around implant after flap folding suture

• Jung SY
• Kang DY
• Shin HS
• Park JC

• KMID: 2525987
• DOI: http://doi.org/10.14368/jdras.2021.37.3.130

Abstract

Purpose
The various suture techniques can be utilized in order to maximize the keratinized tissue healing around dental implants. The aim of this study is to compare the soft tissue healing pattern between two different suture techniques after implant placement.
Materials and Methods
15 patients with 18 implants were enrolled in this study. Simple implant placement without any additional bone graft was performed. Two different suture techniques were used to tug in the mobilized flap near the healing abutment after paramarginal flap design. Digital intraoral scan was performed at baseline, post-operation, stitch out, and 3 months after operation. The scan data were aligned using multiple points such as cusp, fossa of adjacent teeth, and/or healing abutment. After subtracting scan data at baseline with other time-point results, closed space indicating volume increment of peri-implant mucosa was selected. The volume of the close space was measured in mm 3 . The volume between two suture techniques at three time-points was compared using nonparametric rank-based analysis.
Results
Healing was uneventful in both groups. Both suture technique groups showed increased soft tissue volume immediately after surgery. The amount of volume increment significantly decreased after 3 months (P < 0.001). Flap folding suture group showed higher median of volume increment than interrupted suture group after 3 months without any statistical significance (P > 0.05).
Conclusion
After paramarginal flap reflection, the raised flaps stabilized by flap folding suture showed relatively higher volume maintenance after 3-month healing period. However, further studies are warranted.

Keyword

dental implant; keratinized mucosa; sutures; intraoral scanner; clinical trial

Figure

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  Fig. 1 Schematic illustration of flap folding suture.

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  Fig. 2 Clinical photo of flap folding suture. (A) Before surgery, (B) Paramarginal flap design was performed and an implant fixture was placed, (C) Flap folding suture was performed and the mobilized flap is secured down, (D) 3-month healing.

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  Fig. 3 Intraoral scan images of the representative clinical cases for test and control group. (A) Pre-operative, (B) Post-operative, (C) Stitch out, (D) After 3 months.

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  Fig. 4 Measurement of volume change between intraoral scan images. (A) Post-operatvie (white) and pre-operative (blue) scan images were aligned using multiple points of cusp, fossa of adjacent teeth, (B) Aligned scan images, (C) Residual 3D image after Boolean subtraction, (D) Closed spaces indicating volume change of #34 implant (green, flap folding suture) and #35 implant (yellow, interrupted suture).

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  Fig. 5 Representative clinical cases for test and control group. #34 implant received flap folding suture and #35 implant received two interrupted sutures. Healing was uneventful and after 2 months of healing period, final restorations were delivered.

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  Fig. 6 Soft tissue volume change from baseline based on suture technique and time. *: P < 0.0167, **: P < 0.001 from Wilcoxon signed-rank test for post-hoc analysis. Significance level was adjusted according to Bonferroni correction.

Reference

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