Background: Simvastatin (SMV) is a specific competitive inhibitor of 3-hydroxy-2-methyl-glutaryl coenzyme A reductase. Recently, it has been reported that statins promote bone formation. The present study is designed to investigate the effectiveness of 1.2% SMV controlled-release gel associated with the use of an intentionally exposed polyfluoroethylene membrane (PFTM) to decrease dimensional changes in post-extraction sockets.

Aim/Hypothesis: This study aims to evaluate de dimensional changes in post-extraction sockets filling with SMV gel and covered with an intentionally exposed PFTM.

Materials and Methods: Thirty participants requiring extractions of posterior mandibular teeth were randomized in two groups: 1. extractions and socket filling with SNV + PFTM (n = 15; test) and 2. extractions and socket filling with Placebo + PFTM (n = 15; control). Horizontal and vertical dimensions of the hard tissue was assessed using Cone Beam computed tomography (CBCT) scans performed before (T1) and 90 days after (T2) tooth extraction. Four measurements were obtained: Section A, B, C and Depth. Three of them are horizontal, in different sections according to the distance from the most coronal part of crestal bone: 1, 3 and 5 mm (Section A, B and C, respectively), and one is vertical (Depth), from the most apical portion of the socket to the most coronal portion of the bone crest (Figure 1). So, the dimensional changes were evaluated based on these linear measurements, analysing the difference between the groups.

Results: No patient dropped out of the study within 90 days after tooth extraction. Apparently, the two groups were balanced at baseline (table 1). Dimensional alterations data and the statistical analysis are displayed in Figure 2 and Table 2. The bone loss was statistically smaller in the test group in all horizontal sections and Depth.

Conclusions and Clinical Implications: Post-extraction sockets preserved with SMV gel associated with PFTM showed less dimensional changes when compared to sockets preserved with placebo gel. The use of the SNV gel promoted greater expression of bone matrix inside the sockets and, consequently, better preparation of the ridges for future placement of dental implants.

Acknowledgements: This work was supported by the Brazilian agencies Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro - FAPERJ (grant number 202619/17 and 202620/17).

Keywords: Extraction socket, Socket preservation, Simvastatin