Why dental device CERs fail at equivalence claims

Written by HATEM RABEH, MD, MSc Ing

Your Clinical Evaluation Expert And Partner

in
S

The reality is this: dental devices operate in one of the most complex anatomical and microbiological environments in the body. The oral cavity is not a sterile field. It is dynamic, load-bearing, and exposed to constant bacterial colonization. Yet many manufacturers approach clinical evaluation for dental devices as if they were evaluating a simple Class I tool.

That disconnect shows up in the CER. And it costs months of back-and-forth with the Notified Body.

The regulatory baseline: MDR applies fully

Dental devices fall under the MDR like any other medical device. There is no simplified pathway. Whether you manufacture dental implants, restorative materials, orthodontic appliances, or CAD/CAM milling systems, the requirements of MDR Article 61 and Annex XIV apply in full.

This means your clinical evaluation must:

• Demonstrate safety and performance based on clinical data
• Justify equivalence claims with rigorous analysis (if applicable)
• Address all intended uses and clinical claims
• Include a plan for post-market clinical follow-up

But here is where dental devices diverge from other fields: the clinical endpoints, biological interactions, and use environments demand specialty-specific interpretation.

Where equivalence claims break down

Equivalence is a common strategy in dental device submissions. The manufacturer identifies a predicate device, argues similarity, and leverages its clinical data. On paper, it looks reasonable. In practice, it rarely holds up to scrutiny.

Why?

Because dental devices are highly sensitive to material composition, surface properties, and mechanical design. Small differences matter. A titanium dental implant with a sandblasted, acid-etched surface is not equivalent to one with a machined surface, even if both are ‘titanium implants.’ The surface treatment affects osseointegration, bacterial adhesion, and long-term stability.

I have reviewed CERs where manufacturers claimed equivalence based solely on material type and intended use. No discussion of surface roughness. No comparison of thread design. No acknowledgment that bone loading patterns differ based on implant geometry.

The Notified Body reviewer sees this immediately. The equivalence claim collapses. The manufacturer is asked to provide clinical data for their specific device.

What does rigorous equivalence require in dentistry?

For dental devices, equivalence analysis must address:

• Material biocompatibility in the oral environment: Not just ISO 10993 compliance, but interaction with saliva, pH fluctuations, and oral microbiota
• Mechanical performance under cyclic loading: Dental devices endure millions of load cycles. Fatigue resistance and stress distribution are critical.
• Surface properties and bacterial adhesion: Surface roughness, wettability, and biofilm formation directly affect clinical outcomes
• Anatomical and procedural considerations: Implant placement depth, abutment design, and restoration protocols are not interchangeable

If your device differs in any of these dimensions, your equivalence argument weakens. And if you cannot demonstrate clinical equivalence through data, you need your own clinical evidence.

Specialty-specific clinical endpoints

Another challenge: defining what ‘clinical performance’ means for a dental device.

For an implant, is it osseointegration? Marginal bone loss? Implant survival at five years? All of the above?

For a restorative material, is it fracture resistance? Color stability? Marginal adaptation? Biocompatibility with pulp tissue?

For an orthodontic device, is it treatment time? Root resorption? Patient discomfort?

The MDR does not prescribe specific endpoints. But your CER must justify the endpoints you choose. And those endpoints must reflect what matters clinically in the dental field.

I see CERs that cite laboratory data on material strength but provide no clinical data on long-term restoration survival. Or implant studies that report osseointegration rates but ignore peri-implantitis incidence. These gaps are not oversights. They reflect a lack of understanding of what constitutes meaningful clinical evidence in dentistry.

Clinical data sources in dentistry

Where do you find this data?

The dental literature is extensive, but not all of it is useful for MDR purposes. Many studies are small case series. Many lack long-term follow-up. Many do not report adverse events systematically.

Your clinical evaluation must:

• Prioritize controlled studies with clear methodology and defined follow-up periods
• Include data on device-related complications, not just success rates
• Address patient-reported outcomes where relevant (e.g., pain, function, aesthetics)
• Acknowledge limitations in the available literature and explain how PMCF will fill gaps

If your device is novel—new material, new design, new indication—you may need to generate your own clinical data. That means planning a clinical investigation early in development, not scrambling for data when the Notified Body requests it.

The oral microbiome: an underestimated factor

One of the most overlooked aspects of dental device evaluation is the interaction with the oral microbiome.

The mouth harbors hundreds of bacterial species. Some are commensal. Some are pathogenic. All of them form biofilms on device surfaces. This affects every category of dental device: implants, restorations, orthodontic brackets, removable prostheses.

Your CER should address:

• How your device surface affects bacterial adhesion and biofilm formation
• Whether the device material influences local inflammation or immune response
• What the clinical literature says about infection rates and peri-device complications
• How your PMCF plan will monitor microbiological complications in real-world use

I rarely see this in initial CER drafts. Manufacturers focus on mechanical performance and material properties. But when a reviewer with a clinical background reads the CER, they ask: ‘What about biofilm? What about peri-implantitis? What about secondary caries around restorations?’

If those questions are not preemptively answered in your CER, you will be asked to revise it.

PMCF in dentistry: what should you track?

Post-market clinical follow-up is not optional. For dental devices, it is essential.

Why? Because long-term performance matters in dentistry. An implant may integrate successfully at six months but fail at five years due to bone resorption. A restorative material may look stable initially but show marginal deterioration over time.

Your PMCF plan should specify:

• Which clinical endpoints you will monitor (survival, complications, patient satisfaction)
• How you will collect data (registries, clinical studies, systematic literature review updates)
• What triggers a safety signal (e.g., elevated failure rates, unexpected complications)
• How often you will update the CER with new data

For high-risk devices like implants, consider participating in national or international registries. For lower-risk devices, systematic literature surveillance combined with post-market surveillance data may suffice.

But whatever your approach, it must be proactive. Waiting for complaints to accumulate is not PMCF. It is reactive risk management.

What Notified Bodies look for in dental device CERs

When a Notified Body reviews your CER, they are looking for clinical reasoning. Not just data collection. Not just literature summaries. Reasoning.

They want to see that you understand:

• Why your device works the way it does in the oral environment
• What the clinical risks are and how they are mitigated
• Why your clinical data supports your claims and labeling
• How you will monitor performance in real-world use

If your CER reads like a regulatory checklist, it will not pass. If it reads like a clinical discussion grounded in dental science, you have a much better chance.

I have seen both. The difference is not the amount of data. It is the quality of the analysis.

Final thoughts

Dental devices are not exempt from the rigor of MDR clinical evaluation. If anything, they require more attention to specialty-specific factors: surface properties, mechanical loading, microbiological interactions, and long-term performance.

If your CER treats dentistry as a simple application of general medical device principles, expect deficiencies. If it engages with the clinical and biological realities of the oral environment, you are on the right path.

The regulatory bar is not arbitrary. It reflects what is needed to demonstrate that your device is safe and performs as intended in a complex, demanding anatomical site.

Meet that bar, and your submission moves forward. Miss it, and you will be revising your CER while your competitors move to market.