Soft Tissue Alterations in Esthetic Postextraction Sites: A 3-Dimensional Analysis CliniC Al inV ESTi gA Ti O nS

Dimensional alterations of the facial soft and bone tissues follow- ing tooth extraction in the esthetic zone play an essential role to achieve success- ful outcomes in implant therapy. This prospective study is the first to investi- gate the interplay between the soft tis- sue dimensions and the underlying bone anatomy during an 8-wk heal- ing period. The analysis is based on sequential 3-dimensional digital sur- face model superimpositions of the soft and bone tissues using digital impres- sions and cone beam computed tomog- raphy during an 8-wk healing period. Soft tissue thickness in thin and thick bone phenotypes at extraction was sim- ilar, averaging 0.7 mm and 0.8 mm, respectively. Interestingly, thin bone phe- notypes revealed a 7-fold increase in soft tissue thickness after an 8-wk heal- ing period, whereas in thick bone phe- notypes, the soft tissue dimensions remained unchanged. The observed spontaneous soft tissue thickening in thin bone phenotypes resulted in a verti- cal soft tissue loss of only 1.6 mm, which concealed the underlying vertical bone resorption of 7.5 mm. Because of spon- taneous soft tissue thickening, no sig- nificant differences were detected in the total tissue loss between thin and thick bone phenotypes at 2, 4, 6, and 8 wk. More than 51% of these dimensional alterations occurred within 2 wk of healing. Even though the observed spon- taneous soft tissue thickening in thin bone phenotypes following tooth extrac- tion conceals the pronounced underly- ing bone resorption pattern by masking the true bone deficiency, spontane- ous soft tissue thickening offers advan- tages for subsequent bone regenera- tion and implant therapies in sites with high esthetic demand (Clinicaltrials.gov NCT02403700).