Description of the bone-remodeling pattern after socket preservation procedures in human: a methodological study

Background: The bone remodeling after tooth extraction can result in the loss of as much as 50% of the buccal wall and a global crestal reduction in width of 3.87mm according to a recent systematic review. Multiple surgical protocols using biomaterials are proposed in order to limit the typical postextraction bone resorption. However, because of the heterogeneity of the studies and, more specifically, of the assessment methods, it is difficult to assert the superiority of one technique over another. Aim: The objective of this study was to develop a new radiographic method to assess alveolar bone remodeling after socket preservation procedures. Methods: Sixteen extraction sites (in 14 patients) localized in the upper anterior maxilla were treated with bovine hydroxyapatite (0.25–1mm particles) and a saddled connective tissue graft. A radiographic 3-dimensional assessment of the hard tissues was performed at baseline and at 3 months after the procedure. Standardized horizontal measurements were taken at three corono apical levels ( 2, 5, and 9mm) and at three mesio-diatal level (Mesial, Center, and Distal) in the buccal and palatal aspects. Vertical measurements were also recorded in nine regions over the top of the alveolar crest. Results: Extraction socket-preservation technique assessed in the present study significantly reduced horizontal bone remodeling. The horizontal dimension of the crest decreased by 1.6mm (20%) in the cervical regions ( 2mm level), experienced a moderate decrease of 1mm (12%) at the 5mm level, and experienced a very low decrease of 0.5mm(6%) in the apical ( 8mm) level. The losses were always significantly higher in the buccal than in the palatal aspect. Buccally, the maximal bone remodeling at the cervical level remained below 1mm. Vertical bone resorption was homogeneous and was < 1mm in the nine measured regions. Conclusions and clinical implications: The radiographic measuring methodology proved to be accurate and reproducible. It can be applied in other clinical settings. Moreover, the surgical procedure evaluated in the present study, significantly limits the postextraction buccal bone remodeling compared with the data found in the literature for untreated extraction socket in the aesthetic area. However, a complete inhibition of the bone remodeling was not reached and the authors suggest a surgical technique using a ‘‘saddled’’ connective tissue graft to thicken buccal soft tissue biotype and consequently compensate for cervical bone loss