Navigation guided socket-shield technique for implant and pontic sites in the esthetic zone: a proof-of-concept 1-year prospective study with immediate implant placement and loading

Objective To assess clinical, radiological performance of novel navigation guided socket-shield technique (NSS) with immediate implant placement and loading. Materials and Methods Eighteen patients (12 females; age 52.54 +/- 4.92; 33-72) treated between January 2018 and June 2019, were investigated, and followed for at least 1 year after definitive prosthesis placement (mean 20.1 months, 18-23). Primary outcomes: implant and prosthetic success rates, surgical, biologic, prosthetic complications. Secondary outcomes: marginal bone loss (MBL), implant stability quotient (ISQ), pink esthetic score (PES), plaque and bleeding indexes. Results Sixty-nine navigation guided socket-shield procedures were performed (27 implant-sites and 42 pontic-sites) and 27 implants (NobelParallel, NobelBiocare AG) positioned and immediately loaded. Mean insertion torque and ISQ at implant positioning were 49 +/- 5.34 Ncm (36-74), 73 +/- 5.72 (68-81). No implant failure was experienced. Two root-shield exposures with mucositis, ulceration and bleeding were reported at two pontic-sites (2.9%) and successfully treated. No complications were experienced at implant-site leading to an overall NSS success-rate of 100%. No prosthetic complications occurred. Mean MBL was -0.72 +/- 0.26 mm (-0.42 to -1.06 mm). PES final at the last follow-up 12.84 +/- 0.92. The plaque and bleeding scores were 18.5 +/- 6.12 and 3.15 +/- 2.21. Conclusions Within study limitations, dynamic navigation was effective to streamline execution of socket-shield technique at implant and pontic sites, shortening treatment time and reducing complications. Navigation guided socket-shield technique was reliable to achieve digitally planned shield-to-implant distance, facilitate immediate implant placement and loading and establish the mucosal dimension needed for underlying bone-to-implant protection and esthetic integration. Clinical Significance The investigated NSS technique overcomes the difficulties related to root preparation at implant and pontic-sites, facilitating immediate implant placement and loading. Dynamic guided surgery contributed to make socket-shield technique less technical-sensitive, shortening time for execution, reducing complication rate.