Explorative randomized controlled study comparing soft tissue thickness, contour changes, and soft tissue handling of two ridge preservation techniques and spontaneous healing two months after tooth extraction

To compare two ridge preservation techniques and spontaneous healing in terms of soft tissue thickness, contour changes, and soft tissue handling two months after tooth extraction.Thirty-six patients were included with buccal bone plate dehiscences of up to 50% after single-tooth extraction in the esthetic zone. They were randomly assigned to receive one of three procedures: a deproteinized bovine bone mineral with 10% collagen (DBBM-C) covered with a collagen matrix (DBBM-C/CM), DBBM-C alone, or spontaneous healing (SH). Two months later, the status of soft tissue healing was assessed, and the thickness of the mucosa was measured at the center of the site. Thereafter, implants were placed and the need for further guided bone regeneration (GBR) to cover exposed implant surfaces was assessed.Thirty-six patients were evaluated at the day of implant placement. An invagination of the soft tissues was recorded in 41.7% (n = 12), 53.8% (n = 13), and 90.9% (n = 11) of the sites in groups DBBM-C/CM, DBBM-C, and SH, respectively. The median thickness of the mucosa measured was 3.0 mm in group DBBM-C/CM, 2.1 mm in group DBBM-C, and 1.5 mm in group SH. Additional GBR was necessary in 66.7% (n = 12), 53.8% (n = 13), and 90.9% (n = 11) of the sites in groups DBBM-C/CM, DBBM-C, and SH, respectively.The present explorative study revealed slight tendencies for more favorable soft tissue conditions with less invaginations as well as increased soft tissue volume and thickness in groups having received an alveolar ridge preservation procedure compared to spontaneously healed sites at 8 weeks of healing.