Assessment of the stresses produced on the bone implant/tissue interface to the different insertion angulations of the implant - a three-dimensional analysis by the finite elements method

Abstract

Background The present study aimed to assess the stresses produced on the surface of the bone tissue around dental implants with three different insertion angulations subjected to axial and oblique loading. Material and Methods The study was created according to the recommendations of the Checklist for Reporting In-vitro Studies (CRIS). The Straumann™ bone level RC (4.1 x 10 mm) implant, Cone Morse connection (CM), RC Straumann Variobase™ with abutment (3.5 mm) was placed in the region of element 16, with the platform positioned at the height of the bone crest. Three assessment models were produced: model M1 or control - implant perpendicular to the bone crest; model M2 - implant angulated at 17° relative to the bone crest; and model M3 - implant angulated at 30° relative to the bone crest. The masticatory loads were simulated with 100 N of intensity and two loading patterns (axial and oblique) were applied to each model. Then, the models were exported to the finite elements simulation software Ansys Workbench V19.2 (Ansys Inc., Canonsburg, PA, USA). To assess the finite elements, qualitative and quantitative analyses were performed. Results It was observed that, under axial loading, qualitatively, the peaks occurred in the cavosurface region, palatal aspect in M1 and M2, and buccal aspect in M3. Quantitatively, the greatest angulation resulted in a low stress peak. Under oblique loading, qualitatively, the peaks occurred in the cavosurface region, buccal aspect in the three groups. Quantitatively, the greatest angulation of the implant resulted in an increase in stress peaks on the buccal aspect. Conclusions Under axial loading, the three insertion angulations of the implant - M1, M2, and M3 - were clinically viable. When subjected to oblique loading, the 30° angulation (M3) suggested a significant risk of bone loss and it was contraindicated. Key words: Finite element analysis, dental implants, load support.

Implant insertion angle and depth: Peri-implant bone stress analysis by the finite element method

“…Installing implants in inadequate positions may lead to damages to peri-implant bone tissue. Thus, the literature shows that, in angled models subjected to axial or oblique loads, the stability of the implant/prosthesis system was compromised ( 4 ).…”

“…Along with the development of new implant systems, there was an increased need for investigation and research in the field to understand the actual effects of such modernism in the behavior of peri-implant tissues ( 2 , 3 ). Hence, studies assessing bone behavior in the treatment with dental implants have been showing that among the main enemies of peri-implant tissues are the absence of planning and implant placement in sites and positions not recommended by the manufacturers ( 4 ).…”

“…Factors such as the intensity and direction of forces received (axial or oblique) associated with the degree of implant insertion angle to the bone crest may affect directly the stability of the implant-prosthesis system ( 4 ), as well as the total of stresses produced on the surface of peri-implant bone tissue ( 5 - 7 ). Moreover, the levels of stress exerted in the bone tissue were also affected by bone quality and implant insertion depth ( 8 ).…”

Toward Digital Twin Development for Implant Placement Planning Using a Parametric Reduced-Order Model

“…Previous studies have reported a decrease in stress values in the cortical bone with an increase in the implant length and thickness [31][32][33]. Further, the generated stress was reported to increase with an increase in the front-rear and left-right angles of the implant [34][35][36]. The implant placement location has been divided into anterior, premolar, and posterior teeth, and the magnitude of stress has been reported to decrease in the order of posterior teeth, premolars, and anterior teeth [37].…”

Influence of insertion angle and depth on the stresses produced in implants and prosthetic components - a finite element analysis

“…However, the biomechanical behavior of implants, intermediate abutments, and prosthetic crowns can directly affect prosthesis geometry and placement in the mouth (Tian et al, 2012). Implants at the bone level, angled at 30° under oblique loads, suggested a significant bone loss risk (Brum et al, 2020). That disagrees with one of the primary objectives of dental implant treatments, which includes achieving successful results from functional, esthetic, and phonetic standpoints and high long-term predictability and stability (Buser et al, 2017).…”