Virtual and clinical implant placement after ridge preservation in periodontally compromised molars: retrospective study

The purpose of this study is to assess the possibility and needs for bone augmentation in virtual planning and clinical treatment of prosthetically guided dental implants (PGI) following alveolar ridge preservation (ARP) in periodontally compromised molar extraction sites and to analyze the influencing factors. One hundred forty three subjects with 191 molars were included. Radiographic data assessed baseline ridge height and width in variable sites. Virtual implant planning with 4.1/4.8 mm diameter, 8/10 mm length implants was performed using CBCT. The feasibility of simple implant placement and the need for augmentation during implant therapy were assessed. According to the medical records, the implant therapy modalities for sites that received dental implant treatment were also counted. Results of virtual implant planning showed that a few sites (6.81%) required staged augmentation for 4.1 × 8 mm and 4.8 × 8 mm implants, while 59.16% and 45.55% of the sites were possible for simple implant placement, respectively. For all cases clinically treated with implant therapy, 76.1% received simple implant placement, and 3.15% received staged augmentation. Implant treatment modalities were most influenced by location (maxillary/mandible) and the baseline buccal and lingual/palatal bone defects. PGI placement is possible in periodontally compromised molars following ARP, and only a few sites require complicated augmentation procedures. Location and baseline buccal and lingual/palatal bone defects are the influencing factors for implant treatment planning.