Finite Element Analysis of Dental Diamond Burs - Stress Distribution in Dental Structures During Cavity Preparation

At a Glance

Metadata	Details
Publication Date	2025-07-16
Journal	Prosthesis
Authors	K N Chethan, H.N. Abhilash, Afiya Eram, Saniya Juneja, Divya Shetty
Institutions	Manipal Academy of Higher Education
Analysis	Full AI Review Included

Finite Element Analysis of Dental Diamond Burs: Stress Distribution in Dental Structures During Cavity Preparation

(Reference: Chethan K N et al. Prosthesis 2025, 7, 84. MDPI)

Executive Summary

This Finite Element Analysis (FEA) study provides critical insights into the biomechanical stress induced in dental structures by diamond burs, directly informing optimal material selection and clinical protocols.

Core Achievement: Dynamic FEA successfully modeled the stress distribution (von Mises stress) in enamel, dentin, and pulp during simulated cavity preparation using round diamond burs.
Stress Concentration: Maximum stress levels reached 140.43 MPa in dentin, confirming that excessive mechanical load poses a significant risk of structural damage (microcracks, pulpal compromise).
Optimal Protocol: The research strongly recommends using smaller bur diameters (≤2 mm) and shallower depths of cut (DOC ≤1 mm) to minimize stress accumulation and preserve tooth integrity.
Material Behavior: Dentin was identified as the primary load-bearing tissue, acting as a shock absorber due to its higher elasticity compared to brittle enamel.
Tool Rigidity: The simulation modeled the diamond bur as a rigid body, underscoring the necessity of using ultra-hard, high-modulus materials like MPCVD Single Crystal Diamond (SCD) to ensure tool performance matches simulation assumptions.
Future Research Needs: The study highlights the need for future work incorporating tool deformation, statistical analysis, and the influence of heat generated by friction—areas where 6CCVD’s advanced diamond materials can provide solutions.

Technical Specifications

The following hard data points were extracted from the FEA simulation and material modeling parameters:

Parameter	Value	Unit	Context
Maximum Dentin Stress	140.43	MPa	3 mm bur diameter, 2 mm DOC
Maximum Enamel Stress	136.98	MPa	3 mm bur diameter, 1 mm DOC
Minimum Pulpal Stress	0.163	MPa	1 mm bur diameter, 1 mm DOC
Maximum Pulpal Stress	1.036	MPa	3 mm bur diameter, 2 mm DOC
Optimal Bur Diameter	≤2	mm	Recommended for stress minimization
Optimal Depth of Cut (DOC)	≤1	mm	Recommended for stress minimization
Enamel Young’s Modulus (E)	84,000	MPa	Modeled as flexible body
Dentin Young’s Modulus (E)	18,000	MPa	Modeled as flexible body
Pulp Young’s Modulus (E)	2	MPa	Modeled as flexible body
Simulation Mesh Size	0.15	mm	Determined by grid independence study

Key Methodologies

The stress distribution analysis was conducted using a rigorous explicit dynamic Finite Element Analysis (FEA) workflow:

Anatomical Data Acquisition: A three-dimensional human maxillary first molar model was generated from I-CAT 17-19 Computed Tomography (CT) scan data (DICOM format).
CAD Modeling and Refinement: The CT data was processed using 3D Slicer, Fusion 360, and ANSYS Space Claim 2024 R-2 to smooth anatomical features and ensure mesh compatibility for dynamic simulation.
Tool Modeling: Diamond-coated round burs (1 mm, 2 mm, and 3 mm diameters) were modeled using Fusion 360 and defined as rigid bodies in the simulation.
Material Constitutive Model: Dental structures (enamel, dentin, pulp) were defined as deformable bodies utilizing the Cowper-Symonds material model, selected for its capability to simulate high-strain-rate deformation in hard biological tissues without requiring temperature inputs.
Boundary Conditions and Loading: The tooth root surfaces were fixed (all degrees of freedom). Loading involved applying 360° angular rotation and specified depths of cut (1 mm and 2 mm DOC) via remote displacement.
FEA Execution: Explicit dynamic analysis was performed using ANSYS Workbench 2024 R2, with erosion properties enabled for short-term cutting simulations.

6CCVD Solutions & Capabilities

This research validates the critical need for diamond burs manufactured from materials with exceptional rigidity, hardness, and thermal stability to minimize structural damage during high-speed dental procedures. 6CCVD is uniquely positioned to supply the advanced MPCVD diamond materials required to meet and exceed these engineering demands.

Research Requirement/Challenge	6CCVD Solution & Capability	Technical Advantage
Ultra-Rigid Bur Material	Single Crystal Diamond (SCD) Plates: SCD offers the highest Young’s Modulus and hardness available, ensuring the bur maintains the “rigid body” behavior assumed in the FEA model under extreme stress (up to 140 MPa).	Structural Integrity: Minimizes tool deformation and wear, leading to consistent cutting dynamics and reduced risk of microfractures in enamel.
Custom Tool Dimensions & Shapes	Custom MPCVD Diamond Wafers/Plates: We supply SCD and Polycrystalline Diamond (PCD) plates up to 125 mm in diameter, with custom thicknesses ranging from 0.1 µm to 500 µm.	Precision Manufacturing: Provides the necessary material blanks for manufacturers to create the precise 1 mm, 2 mm, and 3 mm round bur geometries tested, including custom laser cutting services.
Addressing Thermal Limitations	Heavy Boron-Doped Diamond (BDD) Substrates: BDD can be integrated into the bur design to function as an in-situ thermal sensor, addressing the study’s limitation regarding unmodeled heat generation.	Integrated Sensing: BDD’s electrical conductivity allows for real-time thermal monitoring during cutting, enabling optimized cooling protocols and preventing pulpal thermal injury.
Advanced Bonding & Coating	In-House Metalization Services: We offer custom deposition of bonding layers (Ti, W) and protective/contact layers (Pt, Au, Pd, Cu) essential for securely adhering diamond grit to the bur substrate.	Enhanced Adhesion: Optimized metalization stacks ensure superior mechanical bonding of the diamond coating, crucial for high-speed rotational applications.
Surface Quality for Reduced Friction	Precision Polishing Services: SCD surfaces polished to Ra < 1 nm and inch-size PCD polished to Ra < 5 nm.	Improved Efficiency: Ultra-smooth diamond surfaces reduce friction and heat buildup, directly supporting the study’s recommendation for controlled cutting methods.

Applicable Materials

To replicate or extend this research, 6CCVD recommends the following materials:

Optical Grade SCD: For the highest mechanical performance and rigidity in the cutting tool body or tip.
Polycrystalline Diamond (PCD): Ideal for robust, large-area bur substrates requiring high thermal conductivity and mechanical stability.
Heavy Boron Doped PCD (BDD): Essential for researchers investigating the thermal effects of cutting, allowing for the integration of electrochemical or thermal sensing capabilities directly into the tool.

Engineering Support

6CCVD’s in-house team of PhD material scientists specializes in optimizing diamond properties for extreme mechanical environments. We offer consultation on material selection, geometry optimization, and metalization strategies for similar high-speed biomedical cutting and FEA validation projects.

Call to Action: For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly. We ship globally (DDU default, DDP available).

View Original Abstract

Background/Objectives: Dental cavity preparation is a critical procedure in restorative dentistry that involves the removal of decayed tissue while preserving a healthy tooth structure. Excessive stress during tooth preparation leads to enamel cracking, dentin damage, and long term compressive pulp health. This study employed finite element analysis (FEA) to investigate the stress distribution in dental structures during cavity preparation using round diamond burs of varying diameters and depths of cut (DOC). Methods: A three-dimensional human maxillary first molar was generated from computed tomography (CT) scan data using 3D Slicer, Fusion 360, and ANSYS Space Claim 2024 R-2. Finite element analysis (FEA) was conducted using ANSYS Workbench 2024. Round diamond burs with diameters of 1, 2, and 3 mm were modeled. Cutting simulations were performed for DOC of 1 mm and 2 mm. The burs were treated as rigid bodies, whereas the dental structures were modeled as deformable bodies using the Cowper-Symonds model. Results: The simulations revealed that larger bur diameters and deeper cuts led to higher stress magnitudes, particularly in the enamel and dentin. The maximum von Mises stress was reached at 136.98 MPa, and dentin 140.33 MPa. Smaller burs (≤2 mm) and lower depths of cut (≤1 mm) produced lower stress values and were optimal for minimizing dental structural damage. Pulpal stress remained low but showed an increasing trend with increased DOC and bur size. Conclusions: This study provides clinically relevant guidance for reducing mechanical damage during cavity preparation by recommending the use of smaller burs and controlled cutting depths. The originality of this study lies in its integration of CT-based anatomy with dynamic FEA modeling, enabling a realistic simulation of tool-tissue interaction in dentistry. These insights can inform bur selection, cutting protocols, and future experimental validations.

Tech Support

Original Source

DOI: https://doi.org/10.3390/prosthesis7040084

References

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