Three-Dimensional Finite Element Analysis of Varying Diameter and Connection Type in Implants with High Crown-Implant Ratio

Abstract

The aim of this study was to evaluate the effect of varying the diameter, connection type and loading on stress distribution in the cortical bone for implants with a high crownimplant ratio. Six 3D models were simulated with the InVesalius, Rhinoceros 3D 4.0 and SolidWorks 2011 software programs. Models were composed of bone from the posterior mandibular region; they included an implant of 8.5 mm length, diameter Ø 3.75 mm or Ø 5.00 mm and connection types such as external hexagon (EH), internal hexagon (IH) and Morse taper (MT). Models were processed using the Femap 11.2 and NeiNastran 11.0 programs and by using an axial force of 200 N and oblique force of 100 N. Results were recorded in terms of the maximum principal stress. Oblique loading showed high stress in the cortical bone compared to that shown by axial loading. The results showed that implants with a wide diameter showed more favorable stress distribution in the cortical bone region than regular diameter, regardless of the connection type. Morse taper implants showed better stress distribution compared to other connection types, especially in the oblique loading. Thus, oblique loading showed higher stress concentration in cortical bone tissue when compared with axial loading. Wide diameter implant was favorable for improved stress distribution in the cortical bone region, while Morse taper implants showed lower stress concentration than other connections.

Comparison of stresses in monoblock tilted implants and conventional angled multiunit abutment-implant connection systems in the all-on-four procedure

“…Moraes et al [ 26 ] examined the effects in the cortical bone around dental implants of different diameters under the application of axial and oblique forces. They reported that wide-diameter implants had lower stress values in the cortical bone than regular diameter implants and axial forces compared to oblique forces.…”

Biomechanical evaluation of stress distribution in subcrestal placed platform-switched short dental implants in D4 bone: In vitro finite-element model study

“…On the contrary, oblique load creates shear forces and lateral movements on the implant, thus leading to more stress on the surrounding bone. [ 29 30 ]…”

“…[ 37 ] The results of this study coincide with other studies that short dental implants affect the peak stress concentration in the cancellous bone as stress values are influenced by implant length. [ 38 39 ] Short and subcrestal dental implants have similar survival rate to regular implant, but the marginal bone loss was lower in short dental implants. [ 40 ] Although platform switch and insertion depths are two independent variables for the marginal bone loss, its synergistic effect can be effective in minimizing crestal bone loss by reducing inflammatory infiltrate and increasing implant–abutment interface from the marginal bone.…”

Comparison of Stresses in Monoblock Tilted Implants and Conventional Angled Multiunit Abutment-implant Connection Systems in the All-on-four Procedure

“…Moraes et al [24] examined the effects in the cortical bone around dental implants of different diameters under the application of axial and oblique forces. They reported that wide-diameter implants had lower stress values in the cortical bone than regular diameter implants and axial forces compared to oblique forces.…”