The Accuracy of The Static Computer-aided Implant Surgery in The Different Extraction Sockets: An In Vitro Study

Abstract

Purpose: To evaluate the accuracy of guided surgery in a healed ridge and different types of maxillary anterior teeth extraction sockets. Material & Methods The extraction site of the maxillary right central incisor (ADA#8) was designed and printed with bone simulation resin. A total of 40 maxillary radiopaque bone models were divided into four groups. Group H (n=10) included the healed edentulous ridge at site #8. Group L (n=10) included #8 extraction socket positioned against the labial cortex. Group C (n=10) included a centralized #8 extraction socket not engaging either the palatal or labial cortices. Group P (n=10) consisted of #8 extraction socket positioned against palatal cortical. Bone models were scanned and saved as STL files. At site #8, a virtual 4.1 mm diameter x 10 mm Straumann bone level tapered implant was planned sub-crestal in a prosthetically-driven position using CoDiagnostiX implant planning software. Surgical guides were fabricated for each bone model according to the implant planning. Straumann BLT implant shape alloy implants were placed following the fully guided s-CAIS protocol. After implant placement, the position was scanned with an intraoral scan, the angular deviation and 3D deviation at the crest and apex levels between the planned and actual implant placement were measured using a treatment assessment function in the implant planning program. One-way ANOVA was used to assess whether the extraction socket form affected the degree and amount of deviation. Result The center group showed the highest global offsets at both the crest (0.83±0.34mm) and apex (0.98±0.29mm), whereas the labial group had the lowest offsets at the crest (0.38±0.17mm) and apex (0.49±0.26mm). Depth deviation of the implant at crest and apex were not significantly different among the groups. The healed ridge group exhibited the highest mean angular deviation (2.91±1.37°), while the center group had the lowest (1.87±1.11°). At the crest, the center group had greater global discrepancies (p < 0.001). ANOVA results indicated that the type of extraction socket significantly affects global, labial-palatal, and mesial-distal deviations at both the crest and apex (p < 0.05). At the apex, the labial group had significantly lower global deviations than the others (p < 0.001). Conclusions The extraction socket types impact the accuracy of s-CAIS. Implants placed immediately in extraction sockets centered within the alveolar ridge showed less accurate crestal positions. In contrast, the labial-positioned socket exhibited greater accuracy in global deviations at the apex. Furthermore, the accuracy of s-CAIS for immediate implant placement was comparable to healed ridge placement with a potential tendency toward a more labial position.