The hidden X suture: a technical note on a novel suture technique for alveolar ridge preservation

Abstract

Purpose: The present study investigated the impact of 2 different suture techniques, the conventional crossed mattress suture (X suture) and the novel hidden X suture, for alveolar ridge preservation (ARP) with an open healing approach.

Methods: This study was a prospective randomized controlled clinical trial. Fourteen patients requiring extraction of the maxillary or mandibular posterior teeth were enrolled and allocated into 2 groups. After extraction, demineralized bovine bone matrix mixed with 10% collagen (DBBM-C) was grafted and the socket was covered by porcine collagen membrane in a double-layer fashion. No attempt to obtain primary closure was made. The hidden X suture and conventional X suture techniques were performed in the test and control groups, respectively. Cone-beam computed tomographic (CBCT) images were taken immediately after the graft procedure and before implant surgery 4 months later. Additionally, the change in the mucogingival junction (MGJ) position was measured and was compared after extraction, after suturing, and 4 months after the operation.

Results: All sites healed without any complications. Clinical evaluations showed that the MGJ line shifted to the lingual side immediately after the application of the X suture by 1.56±0.90 mm in the control group, while the application of the hidden X suture rather pushed the MGJ line slightly to the buccal side by 0.25±0.66 mm. It was demonstrated that the amount of keratinized tissue (KT) preserved on the buccal side was significantly greater in the hidden X suture group 4 months after the procedure (P<0.05). Radiographic analysis showed that the hidden X suture had a significant effect in preserving horizontal width and minimizing vertical reduction in comparison to X suture (P<0.05).

Conclusions: Our study provided clinical and radiographic verification of the efficacy of the hidden X suture in preserving the width of KT and the dimensions of the alveolar ridge after ARP.

Keywords: Alveolar process; Bone regeneration; Bone resorption; Suture techniques; Tooth extraction.

Figure 1

X suture or conventional X suture. The needle passes through over the extraction socket twice as if performing a continuous suture. A large crossed X is created over the socket after suturing. The blue arrows indicate the pulling vectors created by the X suture. X suture, crossed mattress suture.

Figure 2

Criss-cross suture or crossed horizontal external suture. The needle engages the buccal and lingual flaps in the same direction (mesial to distal or distal to mesial), then a knot is created. A large crossed X is created over the socket, as in the X suture. X suture, crossed mattress suture.

Figure 3

Hidden X suture. The needle enters the buccal flap and passes to the opposite side in a diagonal direction, then it passes again from the buccal to the lingual side, also in a diagonal direction. A crossed X is created under the flap, unlike the X suture or criss-cross suture. The blue arrows indicate the vectors created by the hidden X suture. X suture, crossed mattress suture.

Figure 4

The clinical process from baseline to 4 months after ARP. ARP, alveolar ridge preservation; X suture, crossed mattress suture; DBBM-C, demineralized bovine bone matrix mixed with 10% collagen; DL-CM, double-layered collagen membrane; S-O, stitch-out.

Figure 5

CBCT analysis. The horizontal and vertical dimensional changes were measured by comparing the CBCT images taken immediately after the graft (baseline) and before implant surgery (4 months). Scale bar=1 cm. CBCT, cone-beam computed tomographic; X suture, crossed mattress suture.