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

This clinical and radiological pilot study aimed to evaluate soft and hard tissue dimensional changes at extraction sites using digital technology.

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).

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.

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.