Hard and Soft Tissue Dimensional Changes Following Tooth Extraction: A Clinical and Radiological Pilot Study

Objectives: This clinical and radiological pilot study aimed to evaluate soft and hard tissue dimensional changes at extraction sites using digital technology. Methods: Ten teeth were extracted from seven patients referred for simple tooth extractions. Cone-beam computed tomography (CBCT) scans and digital impressions were obtained before tooth extraction and four months after extraction. Virtual models were initially aligned using Medit® Design software (Medit, Seoul, Republic of Korea) and subsequently superimposed onto CBCT images using BlueSkyPlan® software (Blue Sky Bio, LLC, Grayslake, IL, USA). Horizontal and vertical measurements of soft and hard tissue dimensional changes were performed using BlueSkyPlan®. Vertical measurements were obtained at the buccal, central socket, and palatal/lingual aspects. Horizontal measurements were taken at four levels, 2 mm apart, starting at the initial ridge level (L0). Results: Horizontal gingival retraction was 27.40% at L0 and 11.58% at L2. Horizontal hard tissue resorption was 24.39% at L0 and 30.09% at L2. A significant difference in mean soft tissue thickness (at L0 and L2) and hard tissue thickness (at all levels) was observed before and after extraction (p < 0.05). The mean vertical soft tissue retraction was 0.94 ± 0.48 mm buccally and 1.21 ± 0.93 mm lingually. Mean vertical hard tissue resorption was 1.92 ± 1.23 mm buccally and 1.71 ± 0.88 mm lingually. However, no significant differences were observed between buccal and palatal/lingual vertical soft and hard tissue dimensional changes. Conclusion: This study showed that extensive bone resorption and gingival retraction generally occur within four months after tooth extraction. These post-extraction dimensional changes should be considered when establishing surgical and prosthetic treatment plans.