Design-Dependent Electrophysiological Effects of Electrolysis Electrodes Used for Endodontic Disinfection

At a Glance

Metadata	Details
Publication Date	2024-02-09
Journal	Applied Sciences
Authors	Reinhard Bauer, Johannes Ringel, Maximilian Koch, Matthias W. Laschke, Andreas Burkovski
Institutions	Friedrich-Alexander-Universität Erlangen-Nürnberg, Saarland University
Analysis	Full AI Review Included

Technical Documentation & Analysis: BDD Electrodes for Endodontic Disinfection

This document analyzes the research paper “Design-Dependent Electrophysiological Effects of Electrolysis Electrodes Used for Endodontic Disinfection” to provide technical specifications and highlight how 6CCVD’s advanced MPCVD diamond capabilities can support and advance this critical medical technology.

Executive Summary

The research successfully validates the safety and efficacy of specific Boron-Doped Diamond (BDD) electrode designs for electrochemical disinfection in endodontics, provided the design ensures proper shielding.

Core Achievement: Demonstrated that a specific BDD electrode design (Type i) used for electrochemical disinfection caused no detectable electrophysiological effects (ECoG/ECG Score 5/5) in a living mammalian model.
Critical Finding: Electrophysiological safety is critically dependent on the electrode geometry and shielding; the Type i design (anode inside cathode cannula) proved safe, while the Type ii design (anode outside cathode) caused significant disturbances (Score 16.5).
Material Specification: The active component was a 1 µm thick BDD coating deposited on a 50 µm Niobium (Nb) wire, driven by 9 V Direct Current (DC).
Safety Benchmark: The BDD Type i electrode was significantly safer than the reference AC electrotome (Score 18/18), confirming that electrochemical disinfection using optimized BDD is a viable and safe procedure.
Value Proposition: The study underscores the necessity of high-precision material engineering and custom fabrication for BDD medical devices to ensure both functional efficacy and patient safety.

Technical Specifications

The following hard data points were extracted from the research paper detailing the BDD electrode prototypes and experimental results.

Parameter	Value	Unit	Context
Active Material	Boron-Doped Diamond (BDD)	N/A	Used for electrochemical disinfection
BDD Coating Thickness	1	µm	Deposited on Niobium anode wire
Anode Substrate Diameter	50	µm	Niobium (Nb) wire
Cathode Material	Steel	N/A	Endodontic cannula/needle (0.3 x 25 mm)
Applied Voltage	9	V	Direct Current (DC)
Current Type	DC	N/A	Used for electrolysis and radical production
Stimulation Duration	<20	s	Time applied to opened tooth cavities
BDD Type i Score (Median)	5 (5; 5)	N/A	Electrophysiological Significance (Harmless)
BDD Type ii Score (Median)	16.5 (12; 17)	N/A	Electrophysiological Significance (Strong Effects)
Reference Electrotome Score	18 (18; 18)	N/A	Highest score (due to electromagnetic interference)
Internal Body Resistance	Approximately 1	kΩ	Total internal resistance of the human body

Key Methodologies

The experimental design focused on comparing the electrophysiological impact of different BDD electrode geometries under controlled in vivo conditions.

Material Preparation: Anodes were fabricated using a 50 µm Niobium (Nb) wire coated with a precise 1 µm layer of Boron-Doped Diamond (BDD) via MPCVD.
Electrode Design (Type i - Safe): The BDD-coated Nb anode was positioned inside a steel endodontic cannula (cathode), separated by a thin polymeric insulating layer. This design minimized current spread.
Electrode Design (Type ii - Unsafe): The BDD-coated Nb anode was positioned outside the steel endodontic cannula (cathode), increasing unshielded contact potential.
In Vivo Application: Electrodes were introduced into trepanned tooth cavities in anesthetized Sprague-Dawley rats for short periods (<20 s).
Electrical Parameters: Stimulation utilized 9 V Direct Current (DC), verified by visual observation of intracavitary gas bubble production (electrolysis).
Monitoring: Electrocorticogram (ECoG) and Electrocardiogram (ECG) signals were continuously recorded, filtered (0.5-45 Hz for ECoG, 0.1-1000 Hz for ECG), and stored at 1000 Hz.
Data Analysis: Effects were quantified using an Electrophysiological Significance Score (1-18), classifying outcomes from “harmless” (5-8) to “strong effects” (14-18).

6CCVD Solutions & Capabilities

The success of BDD electrodes in endodontic disinfection hinges entirely on precise material engineering and custom integration, areas where 6CCVD provides world-leading expertise. The research confirms that material quality and design are inseparable from safety and performance.

Research Requirement/Challenge	6CCVD Capability Match	Engineering Value Proposition
Applicable Materials	Heavy Boron-Doped Diamond (BDD) for high electrochemical efficiency and stability.	We supply high-quality BDD material (PCD or SCD) with customizable doping levels, ensuring optimal conductivity and radical generation for electrochemical applications.
Precision Thickness Control	Requirement for a highly controlled 1 µm BDD coating on the anode.	6CCVD specializes in growing SCD and PCD layers with thickness control from 0.1 µm up to 500 µm. We guarantee the precise 1 µm thickness required for reproducible device performance.
Custom Substrate Integration	Coating a 50 µm Niobium wire and integrating it into a complex cannula structure.	Our internal metalization capabilities (Au, Pt, Pd, Ti, W, Cu) and expertise in thin-film deposition allow us to engineer BDD coatings on custom refractory metal substrates and complex micro-geometries required for medical probes.
Miniaturization & Polishing	Need for smooth, precise electrode tips for insertion into root canals.	We offer ultra-smooth polishing down to Ra < 1 nm for SCD and Ra < 5 nm for inch-size PCD, critical for minimizing friction and ensuring biocompatibility during insertion.
Design Validation & Safety	The study proved that design (shielding/geometry) is the critical safety factor.	Engineering Support: 6CCVD’s in-house PhD team can assist with material selection, design optimization, and integration strategies for similar Electrochemical Disinfection projects, ensuring compliance with stringent medical device safety standards.
Scalability for Production	Need for reproducible, high-volume BDD components for clinical devices.	We offer custom dimensions for PCD plates/wafers up to 125mm, enabling efficient scale-up and high-throughput micro-fabrication necessary for commercial medical device manufacturing.

For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.

View Original Abstract

Electrochemical disinfection in dentistry using boron-doped diamond (BDD) electrodes bears the potential risk of disturbing vital functions. Applying different arrays of BDD electrodes and an electrotome as reference, it was the goal of this animal study to compare their effects on an electrocorticogram (ECoG) and electrocardiogram (ECG). Following the trepanation of teeth in rats, the electrodes and electrotome were applied in a randomized manner while recording ECoG and ECG. The recordings were classified according to an electrophysiological significance score based on involvement, extent of disruption and duration. The scores obtained were compared by means of ANOVA followed by Dunn’s multiple comparisons test (α = 0.05). Voltage type and electrode design had a significant influence on the detectable electrophysiological effects. The results seen with BDD electrodes ranged from no detectable electrophysiological effects to a pronounced effect. The application of the electrotome induced the most pronounced effects. Given that electrotomes are safe medical devices, despite evoking greater disturbance compared to BDD electrodes, regardless of their design, electrochemical disinfection may be considered a safe procedure.

Tech Support

Original Source

DOI: https://doi.org/10.3390/app14041445

References

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