Background: Tooth loss causes alveolar bone resorption, which may hinder the ability of implant placement. Socket preservation with immediate implant placement is one of the methods used to reduce bone resorption. In this retrospective study, we evaluated the influence of the use of dense polytetrafluoroethylene (d-PTFE) membranes on alveolar preservation after tooth extraction and with the installation of immediate dental implants. Methods: In this retrospective study, one hundred and four patients were divided into two groups: immediate implant and gap filling with heterogenous bone graft (control group, 52 patients) or immediate implant, gap filling with heterogenous bone graft, and covering with a d-PTFE membrane with dimensions of 12 × 24 mm, which was intentionally left exposed to the oral cavity (test group, 52 patients). Tomographic data were obtained before and 12 months after the surgical procedures. Results: The membranes exposed in the oral cavity showed no infection. Volumetric analyses revealed a statistically significant difference in alveolar ridge resorption for the control and d-PTFE groups, 16.75% and 4.55%, respectively. Conclusions: Intentionally exposed d-PTFE membranes showed minimal complications. Based on the volumetric results, alveolar ridge preservation with d-PTFE membranes was superior to the bone graft alone in immediate implant placement.