Pilot Study on the Use of a Laser-Structured Double Diamond Electrode (DDE) for Biofilm Removal from Dental Implant Surfaces

At a Glance

Metadata	Details
Publication Date	2020-09-21
Journal	Journal of Clinical Medicine
Authors	Maximilian Koch, Andreas Burkovski, Manuel Zulla, Stefan Rosiwal, Walter Geißdörfer
Institutions	Straumann (Switzerland), Friedrich-Alexander-Universität Erlangen-Nürnberg
Citations	14
Analysis	Full AI Review Included

Technical Documentation & Analysis: Laser-Structured BDD Electrodes for Biofilm Removal

Reference: Koch et al. (2020). Pilot Study on the Use of a Laser-Structured Double Diamond Electrode (DDE) for Biofilm Removal from Dental Implant Surfaces. J. Clin. Med. 2020, 9, 3036.

Executive Summary

This pilot study successfully validates the use of Boron-Doped Diamond (BDD) electrodes for electrochemical disinfection, presenting a significant advancement in treating peri-implantitis.

Novel Device: A Laser-Structured Double Diamond Electrode (DDE) array was fabricated on a non-conductive ceramic carrier, demonstrating clinical applicability and miniaturization potential.
Superior Efficacy: Electrochemical disinfection using the BDD electrode was significantly more effective at eliminating wild-type multispecies biofilm from roughened Ti-Zr surfaces than conventional chemo-mechanical treatment (curettes + chlorhexidine).
Mechanism: The BDD anode generates highly oxidative species (primarily hydroxyl radicals), achieving massive reduction and near-complete removal of both bacteria and the protective polymer biofilm matrix.
Key Achievement: Complete inactivation of multispecies biofilm on complex dental implant surfaces was achieved in just 2.5 minutes at 9 V potential (105 mA average current).
Optimization Required: The study concludes that further optimization of BDD layer thickness, doping level, and electrode geometry is necessary to maximize charge quantity and application time for optimal disinfection without harming host tissue.
6CCVD Value: 6CCVD is uniquely positioned to supply the custom BDD materials, precise laser structuring, and robust metalization required to transition this promising technology into certified clinical devices.

Technical Specifications

The following hard data points were extracted regarding the BDD electrode design and performance parameters:

Parameter	Value	Unit	Context
Electrode Material	Boron-Doped Diamond (BDD)	N/A	Deposited via Hot Filament CVD (HFCVD)
Substrate Material	Porcelain	N/A	Non-conductive ceramic carrier
BDD Layer Thickness	$\sim 5$	µm	Thickness of the conductive diamond film
Laser Structuring Gap	$\sim 50$	µm	Separating anode and cathode (DDE structure)
Active Electrode Area	$3 \times 5$	mm²	Electrochemically active surface area
Applied Potential (Low)	6	V	Used for initial disinfection tests
Applied Potential (High)	9	V	Used for optimized disinfection and implant tests
Average Current (6 V)	50	mA	Measured during 6 V application
Average Current (9 V)	115 (105 for implants)	mA	Measured during 9 V application
Treatment Time Range	2.5 to 5	min	Tested duration for electrochemical disinfection
Biofilm Removal (5 min DDE)	Almost complete removal	N/A	Quantified via UV/Vis measurement at 570 nm
Implant Disinfection Time	2.5	min	Time required for complete inactivation at 9 V/105 mA
Surface Roughness Threshold	0.2	µm	R(a) value cited for biofilm formation studies

Key Methodologies

The fabrication of the Double Diamond Electrode (DDE) and the electrochemical disinfection process relied on precise CVD and structuring techniques:

BDD Film Deposition: The conductive diamond layer was grown onto a non-conductive ceramic substrate (porcelain) using a standard Hot Filament Chemical Vapor Deposition (HFCVD) process.
Boron Doping: Conductivity was imparted to the diamond film by introducing B(OCH₃)₃ gas during the CVD process, resulting in a heavily doped, conductive BDD layer ($\sim 5$ µm thick).
DDE Structuring: A laser structuring process was employed to precisely cut the BDD layer, creating a $\sim 50$ µm gap. This cut electrically separated the BDD film into distinct anode and cathode zones on the single ceramic carrier, forming the DDE array.
Electrical Contacting: Electrical contacts (copper cable strand) were attached to the BDD layer using conductive silver paint, which was subsequently insulated with glue to protect the contact zone from the reactive electrolyte.
Biofilm Model: Roughened Ti-Zr discs (5 mm diameter) were mounted on maxillary splints and exposed intraorally for 24 hours to generate wild-type multispecies biofilm.
Electrochemical Disinfection: Discs were immersed in 0.9% NaCl solution (electrolyte) and treated using the DDE at controlled potentials (6 V or 9 V) and durations (2.5 min or 5 min).
Efficacy Assessment: Disinfection efficacy was measured by pressing the treated discs onto Columbia blood agar plates (bacterial survival) and quantifying the remaining biofilm mass using crystal violet staining (UV/Vis at 570 nm).

6CCVD Solutions & Capabilities

The research highlights the critical need for highly customized, precision-engineered BDD materials to advance electrochemical disinfection technology. 6CCVD is the ideal partner to meet these stringent requirements, offering materials and services that exceed the capabilities used in this pilot study.

Research Requirement	6CCVD Solution & Capability	Technical Advantage
High-Performance BDD Material	Heavy Boron-Doped PCD or SCD Wafers	We supply BDD with optimized doping levels for maximum electrochemical efficiency, ensuring high production rates of hydroxyl radicals necessary for rapid, complete disinfection.
Precise Thin Film Control	SCD/PCD Thickness Range (0.1 µm - 500 µm)	The study used $\sim 5$ µm films. 6CCVD guarantees precise, uniform thickness control, enabling researchers to fine-tune charge quantity and optimize the BDD layer for specific voltage/current requirements.
Miniaturization & Geometry Adaptation	Advanced Laser Cutting and Custom Dimensions	The paper stresses the need to reduce size and adapt geometry. 6CCVD offers high-precision laser structuring to replicate the $\sim 50$ µm DDE gap and create complex, application-specific electrode shapes for dental probes.
Robust Electrical Interconnects	Internal Metalization Services (Ti, Pt, Au, W, Cu)	We replace unreliable conductive paints with robust, high-adhesion metal stacks (e.g., Ti/Pt/Au) deposited directly onto the BDD surface, ensuring long-term stability and reliability in clinical environments.
Large-Scale Array Manufacturing	PCD Plates up to 125 mm Diameter	For scaling up production of DDE arrays, 6CCVD provides large-area Polycrystalline Diamond (PCD) wafers, facilitating high-throughput manufacturing of ceramic-based electrode carriers.
Surface Finish Optimization	Polishing Capabilities (Ra < 5 nm for PCD)	We can provide highly polished BDD surfaces, which may be critical for minimizing potential tissue irritation while maintaining electrochemical activity, addressing the study’s concern regarding host tissue harm.

Engineering Support

6CCVD’s in-house PhD team specializes in the electrochemical properties of diamond. We offer comprehensive engineering support for projects focused on electrochemical disinfection, peri-implantitis treatment, and advanced medical device development. We assist clients in selecting the optimal BDD material specifications (doping concentration, thickness, and substrate integration) to achieve superior performance and regulatory compliance.

Call to Action: For custom specifications or material consultation regarding BDD electrodes for medical or electrochemical applications, visit 6ccvd.com or contact our engineering team directly.

View Original Abstract

No proper treatment option for peri-implantitis exists yet. Based on previous studies showing the in vitro effectiveness of electrochemical disinfection using boron-doped diamond electrodes, novel double diamond electrodes (DDE) were tested here. Using a ceramic carrier and a laser structuring process, a clinically applicable electrode array was manufactured. Roughened metal discs (n = 24) made from Ti-Zr alloy were exposed to the oral cavities of six volunteers for 24 h in order to generate biofilm. Then, biofilm removal was carried out either using plastic curettes and chlorhexidine digluconate or electrochemical disinfection. In addition, dental implants were contaminated with ex vivo multispecies biofilm and disinfected using DDE treatment. Bacterial growth and the formation of biofilm polymer were determined as outcome measures. Chemo-mechanical treatment could not eliminate bacteria from roughened surfaces, while in most cases, a massive reduction of bacteria and biofilm polymer was observed following DDE treatment. Electrochemical disinfection was charge- and time-dependent and could also not reach complete disinfection in all instances. Implant threads had no negative effect on DDE treatment. Bacteria exhibit varying resistance to electrochemical disinfection with Bacillus subtilis, Neisseria sp., Rothiamucilaginosa, Staphylococcus haemolyticus, and Streptococcus mitis surviving 5 min of DDE application at 6 V. Electrochemical disinfection is promising but requires further optimization with respect to charge quantity and application time in order to achieve disinfection without harming host tissue.

Tech Support

Original Source

DOI: https://doi.org/10.3390/jcm9093036

References

2016 - Effectiveness of implant therapy analyzed in a Swedish population: Prevalence of peri-implantitis [Crossref]
2016 - “Peri-implantitis”: A complication of a foreign body or a man-made “disease”. Facts and fiction [Crossref]
2015 - Primary prevention of peri-implantitis: Managing peri-implant mucositis [Crossref]
2018 - How frequent does peri-implantitis occur? A systematic review and meta-analysis [Crossref]
2000 - Initial and long-term crestal bone responses to modern dental implants [Crossref]
2012 - Crestal bone loss and oral implants [Crossref]
2009 - Short-term clinical and microbiological evaluations of peri-implant diseases before and after mechanical anti-infective therapies [Crossref]
2020 - Development of a peri-implantitis model in the rat [Crossref]
2014 - Management of peri-implant mucositis and peri-implantitis [Crossref]