Soft tissue contour and radiographic evaluation of ridge preservation in early implant placement: A randomized controlled clinical trial

OBJECTIVES To compare two ridge preservation techniques and spontaneous healing in terms of hard and soft tissue changes 2 months after tooth extraction. MATERIAL AND METHODS The study was designed as a randomized controlled trial and included 75 patients. After single tooth extraction in the maxillary incisor/premolar area, patients were randomly allocated to one of the following groups: 1) ridge preservation with a xenogeneic bone substitute covered with a collagen matrix (CM-group), 2) ridge preservation with a xenogeneic bone substitute covered with a free palatal graft (PG-group) or 3) spontaneous healing (control). Eight weeks after tooth extraction, implants were placed and clinical, profilometric and radiographic evaluations were performed. In addition, the need for further guided bone regeneration (GBR) at implant placement was assessed. The differences between the treatment groups were compared with the One-way ANOVA or Kruskal-Wallis test with the corresponding post hoc analysis. The proportions of the categorical parameters were compared with the Fisher´s exact test. RESULTS Seventy-five patients underwent early implant placement 8 weeks after tooth extraction and were evaluated. CM-group (-0.9 SD 0.6 mm) and PG-group (-1.0 SD 0.8 mm) showed less horizontal bone resorption compared to the control group (-3.2 SD 2.1 mm) (p<.001). Moreover, the necessity of GBR at implant placement was significantly less in CM-group (32%) and PG-group (24%) when compared to control group (72%) (p=.001). Patients in CM-group experienced less pain than PG-group, one week after tooth extraction (p=.042). No significant differences were found regarding graft evaluation, post-operative complications and soft tissue contour. CONCLUSIONS Ridge preservation using a xenogeneic bone substitute covered with a collagen matrix or a palatal graft, results in less bone resorption and fewer GBR procedures at early implant placement compared to spontaneous healing.