Periodontal phenotype and supracrestal soft tissue dimensions â•fi clinical correlations and their impact on post-extraction volumetric changes

Objectives: Extraction of a tooth leads to a series of healing events that are intimately associated with dimensional changes in the alveolar ridge that typically result in a net volume loss. Previous studies have evaluated the extent and pattern of those resorptive changes, however it remains challenging to predict the degree of change that will occur, as numerous local and systemic factors may play a role in the biologic events that follow tooth extraction. The purpose of this study was to assess the role that phenotypic characteristics of the periodontium play in the alveolar ridge remodeling processes that take place following single tooth extraction. Methods: Healthy patients in need of a single tooth extraction in the maxillary arch from second premolar to second premolar (inclusive) and who met a predefined eligibility criteria were enrolled in this study. An impression of the maxillary arch was made and a cone beam computed tomography (CBCT) scan of the maxilla was obtained immediately prior to tooth extraction at the baseline visit. At the time of the extraction, clinical measurements were made including probing depth, bone sounding, buccal keratinized mucosa width, buccal and palatal alveolar bone thickness, and buccal and palatal soft tissue thickness. Fourteen weeks following the baseline intervention, patients returned to the clinic for a second impression of the maxillary arch and a second CBCT of the maxilla. Linear and volumetric bone measurements were made using the data obtained from the CBCT scans. The casts obtained from the impressions were digitally scanned and volumetric measurements were made from the digitized data to assess volume changes of the residual ridge. The primary outcome of interest was the volumetric percent reduction of the alveolar ridge following single tooth extraction. Spearman correlations were utilized to evaluate