In the literature, many researchers investigated static loading effects on an implant. However, dynamic loading under impact loading has not been investigated formally using numerical methods. This study aims to evaluate, with 3D finite element analysis (3D FEA), the stress transferred (maximum peak and variation in time) from a dynamic impact force applied to a single implant-supported prosthesis made from different materials. A 3D implant-supported prosthesis model was created on a digital model of a mandible section using CAD and reverse engineering. By setting different mechanical properties, six implant-supported prostheses made from different materials were simulated: metal (MET), metal-ceramic (MCER), metal-composite (MCOM), carbon fiber-composite (FCOM), PEEK-composite (PKCOM), and carbon fiber-ceramic (FCCER). Three-dimensional FEA was conducted to simulate the collision of 8.62 g implant-supported prosthesis models with a rigid plate at a speed of 1 m/s after a displacement of 0.01 mm. The stress peak transferred to the crown, titanium abutment, and cortical bone, and the stress variation in time, were assessed.

Some evidence supports the influence of implant macro-design on primary stability. Additionally, tactile perception can be used to assess implant stability when placing the implant. This research aimed to quantify the primary and secondary stability of three implant systems with two different macro geometries (cylindrical and conical) determined based on the insertion torque and the implant stability quotient (ISQ) at the moment of implant placement as a function of implant-related factors (length, width, dental arch, and implant location in the arch), intraoperative factors (bone density determined subjectively by the clinician’s tactile perception), and patient-related factors (age, gender, and bone density determined objectively based on cone beam computed tomography (CBCT). Methods: 102 implants from three implant systems with two different macro geometries (conical and cylindrical) were placed in 53 patients. The insertion torque, the ISQ at the implant placement (ISQ0), and the bone quality according to the clinician’s tactile sensation were recorded on the day of the surgery. After a three-month healing period, the ISQ was re-evaluated (ISQ3). Results: The cylindrical implants exhibited significantly higher insertion torque and ISQ values at the moment of the surgery and after three months compared to the conical implants. The cylindrical implants also showed significantly lower indices of tactile evaluation of bone quality during the implant placement surgery. However, no differences were demonstrated in the bone density measured objectively using CBCT. (4) Conclusions: The cylindrical implants achieved the highest values for primary stability (Newtons × centimeter (Ncm) and ISQ) and secondary stability (ISQ after three months). The insertion torque was the variable that most influenced the ISQ on the day of the surgery. The implant location (incisors–canines, bicuspids–molars) and the implant macro geometry were the variables that most influenced the secondary stability (ISQ at three months).

Statement of problem: Nowadays, milling is still the gold standard for fabricating indirect restorations, but to overcome its disadvantages, there are alternatives, such as 3D printing. Purpose: This study aimed to compare the gaps between the prepared tooth and milled and printed onlays fabricated with the same CAD design. It also aimed to determine the gap reproducibility across onlays fabricated by 3D printing and milling. Methods: A resin tooth was prepared for an onlay. After scanning the preparation, an onlay was designed with proprietary dental software. Next, 22 onlays were milled in a graphene-reinforced PMMA disc (Group 1), and 22 onlays were 3D-printed with a hybrid composite material (Group 2). After that, all fabricated restorations were scanned and superimposed on the scanned prepared resin tooth. Subsequently, a specific software was used to measure the margin, central, and intaglio-located gap between the milled or printed restoration and the preparation. Finally, measurements were compared with a multifactor analysis of variance. Results: The results demonstrated that printed onlays (Group 2) adapted better to the prepared tooth than the milled ones (Group 1) (p < 0.05). The comparison of standard deviations showed the better gap reproducibility of printed onlays (p < 0.05). Conclusion: This study concluded that the printed onlays adapted significantly better to the prepared tooth than the milled onlays. Printed onlays also showed significantly better gap reproducibility.