Forensic DentistryOVERLAY-REPRONCT07552051
Reproducibility of Dental Bite Mark Overlay Analysis Using Digital 3D Models in Adult Participants
An observational study of Forensic Dentistry and Bite Mark Analysis, run by Nantes University Hospital at 1 site in France.
Trial summary
This study aims to evaluate the reproducibility and repeatability of a standardized digital overlay protocol used in forensic odontology for bite mark analysis. Bite mark analysis methods have been increasingly questioned due to concerns about their scientific reliability. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Forensic Dentistry, Bite Mark Analysis
- What is being tested?
- 3D Digital Model Overlay Analysis
- How many people
- 30 participants
- Where
- 1 siteFrance
- Study dates
- 1 Apr 2026to Jun 2027
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Adult participants recruited among patients attending a dental clinic for routine care requiring intraoral optical scanning.
Who may be able to join
- Age ≥18 years
- Patients requiring dental care including intraoral optical scan
- Able to understand the study and provide informed consent
- Sufficient dentition allowing usable maxillary scan
Who cannot join
- Age <18 years
- Individuals under legal protection (guardianship or curatorship)
- Oral conditions preventing intraoral scanning
- Refusal to participate
- Completely edentulous patients
- Partially edentulous patients (>8 missing maxillary teeth)
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
France1 site, 1 recruiting
- Recruiting
CHU Nantes-Department of Dentistry
Nantes, Nantes, 44000
Alexandra Poinas, PhD, +33 2 40 08 33 33, alexandra.poinas@chu-nantes.fr
About this study
Official title: Reproducibility and Repeatability of Digital Overlay Techniques in Bite Mark Morphological Analysis: An Observational Study Using 3D Dental Models
This study aims to evaluate the reproducibility and repeatability of a standardized digital overlay protocol used in forensic odontology for bite mark analysis. Bite mark analysis methods have been increasingly questioned due to concerns about their scientific reliability. This study focuses on the methodological evaluation of an overlay generation protocol independently of biological trace interpretation.
Thirty adult participants requiring routine dental care involving intraoral scanning will be included. A digital impression of the maxillary dentition will be obtained using a standard intraoral scanner, which is a non-invasive and routine clinical procedure.
Read more
Digital dental models will be anonymized and processed using dedicated software to generate overlays. Four operators with different levels of expertise will independently perform the overlay procedure at two separate time points.
The study will assess intra-operator repeatability and inter-operator reproducibility using quantitative 2D and 3D metrics. The objective is to determine the variability of the protocol and to contribute to the standardization and reliability of overlay-based analyses in forensic dentistry.
Read the detailed description
This is a prospective methodological study designed to evaluate the reproducibility and repeatability of a standardized digital overlay protocol used in forensic odontology.
Background:
Bite mark analysis has been increasingly challenged due to concerns regarding its scientific validity and reliability. In this context, there is a need to assess the methodological robustness of tools used in this field, particularly digital overlay techniques used for comparison purposes.
Objectives:
The primary objective is to assess intra-operator repeatability and inter-operator reproducibility of a standardized overlay generation protocol. Secondary objectives include evaluating the influence of operator expertise and testing quantitative metrics for overlay comparison.
Methods:
Thirty adult participants undergoing routine dental care involving intraoral scanning will be recruited. Participation involves a single, non-invasive intraoral scan of the maxillary dentition, performed using a standard optical scanner.
Digital dental models will be anonymized and exported in STL and PLY formats. A standardized overlay protocol will then be applied using CloudCompare and complementary image processing software.
Four operators with different levels of expertise will independently generate overlays from each model at two separate time points (T1 and T2), spaced by several days, in order to assess repeatability and reproducibility.
Outcome Measures:
Quantitative analysis will be performed using 2D and 3D metrics, including distances between point clouds, root mean square deviation (RMS), and surface overlap measurements.
Data Management:
Only anonymized digital models and limited demographic data (age and sex) will be collected. Data will be stored on secure systems with restricted access and will not be transferred outside the European Union.
Ethics:
The study involves minimal risk, as intraoral scanning is a routine, non-invasive procedure. No biological samples are collected, and no additional interventions are performed beyond standard care.
Significance:
This study aims to provide objective data on the variability of overlay generation methods and to contribute to the standardization and scientific reliability of forensic dental analyses.
- Conditions
- Forensic Dentistry, Bite Mark Analysis
- Being tested
- 3D Digital Model Overlay Analysis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
3D Digital Model Overlay AnalysisOther
Standardized overlay protocol applied to digital dental models (STL/PLY files). Each model is analysed twice by each of four operators at two separate time points (T1 and T2) to assess intra- and inter-operator reproducibility.
| Study group | Role | What they receive |
|---|---|---|
| Participants undergoing digital dental model analysis | Single cohort of adult participants undergoing a single intraoral digital scan. Digital models are subsequently analysed by four independent operators at two separate time points (T1 and T2) to assess intra- and inter-operator reproducibility. Receives: Other: 3D Digital Model Overlay Analysis |
What is being measured
The primary outcome is the main question the study is designed to answer.
Intra-operator Reproducibility of Overlay Concordance Measurements
Agreement between repeated overlay analyses performed by the same operator on the same digital maxillary model across two measurement sessions
Measured: Baseline and Day 7 (±2 days)
Secondary outcomes (4)
Inter-operator Reproducibility of Overlay Concordance Measurements
Agreement between overlay analyses performed by different operators on the same digital maxillary model, assessed using quantitative concordance indicators generated from the standardized overlay protocol.
Measured: Baseline and Day 7 (±2 days)
Distance Between Point Clouds in 3D Overlay Analysis
Three-dimensional distance between point clouds generated during overlay comparison of digital maxillary models, assessed using dedicated 3D analysis software. Higher values indicate greater discrepancy between overlays.
Measured: Baseline and Day 7 (±2 days)
Surface Overlap in Digital Overlay Analysis
Surface overlap measured during comparison of digital maxillary overlays using standardized image processing and 3D analysis methods. Higher values indicate greater overlap between overlays.
Measured: Baseline and Day 7 (±2 days)
Influence of Operator Expertise on Overlay Reproducibility
Comparison of overlay reproducibility metrics according to operator expertise level across repeated analyses of the same digital maxillary models.
Measured: Baseline and Day 7 (±2 days)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Apr 2026
- Study start1 Apr 2026
- Primary completionJun 2027 (estimated)
- Study completionJun 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Forensic DentistryStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case only
- Time perspective
- Prospective
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Nantes University Hospital
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07552051
- Sponsor's protocol ID
- AP_LMC_SG_OVERLAY-REPRO
- Acronym
- OVERLAY-REPRO
- Status last verified
- Jun 2026
- First submitted
- 20 Apr 2026
- Last updated
- 24 Jun 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 24 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Reproducibility and Repeatability of Digital Overlay Techniques in Bite Mark Morphological Analysis: An Observational Study Using 3D Dental Models
- ClinicalTrials.gov ID
- NCT07552051
- Acronym / sponsor ID
- OVERLAY-REPRO / AP_LMC_SG_OVERLAY-REPRO
- Conditions
- Forensic Dentistry, Bite Mark Analysis
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- Nantes University HospitalUniversity, hospital or other
- Study start
- 1 Apr 2026 (actual)
- Primary completion
- Jun 2027 (estimated)
- Study completion
- Jun 2027 (estimated)
- First posted
- 27 Apr 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study aims to evaluate the reproducibility and repeatability of a standardized digital overlay protocol used in forensic odontology for bite mark analysis. Bite mark analysis methods have been increasingly questioned due to concerns about their scientific reliability. This study focuses on the methodological evaluation of an overlay generation protocol independently of biological trace interpretation.
Thirty adult participants requiring routine dental care involving intraoral scanning will be included. A digital impression of the maxillary dentition will be obtained using a standard intraoral scanner, which is a non-invasive and routine clinical procedure.
Digital dental models will be anonymized and processed using dedicated software to generate overlays. Four operators with different levels of expertise will independently perform the overlay procedure at two separate time points.
The study will assess intra-operator repeatability and inter-operator reproducibility using quantitative 2D and 3D metrics. The objective is to determine the variability of the protocol and to contribute to the standardization and reliability of overlay-based analyses in forensic dentistry.
Detailed description
This is a prospective methodological study designed to evaluate the reproducibility and repeatability of a standardized digital overlay protocol used in forensic odontology.
Background:
Bite mark analysis has been increasingly challenged due to concerns regarding its scientific validity and reliability. In this context, there is a need to assess the methodological robustness of tools used in this field, particularly digital overlay techniques used for comparison purposes.
Objectives:
The primary objective is to assess intra-operator repeatability and inter-operator reproducibility of a standardized overlay generation protocol. Secondary objectives include evaluating the influence of operator expertise and testing quantitative metrics for overlay comparison.
Methods:
Thirty adult participants undergoing routine dental care involving intraoral scanning will be recruited. Participation involves a single, non-invasive intraoral scan of the maxillary dentition, performed using a standard optical scanner.
Digital dental models will be anonymized and exported in STL and PLY formats. A standardized overlay protocol will then be applied using CloudCompare and complementary image processing software.
Four operators with different levels of expertise will independently generate overlays from each model at two separate time points (T1 and T2), spaced by several days, in order to assess repeatability and reproducibility.
Outcome Measures:
Quantitative analysis will be performed using 2D and 3D metrics, including distances between point clouds, root mean square deviation (RMS), and surface overlap measurements.
Data Management:
Only anonymized digital models and limited demographic data (age and sex) will be collected. Data will be stored on secure systems with restricted access and will not be transferred outside the European Union.
Ethics:
The study involves minimal risk, as intraoral scanning is a routine, non-invasive procedure. No biological samples are collected, and no additional interventions are performed beyond standard care.
Significance:
This study aims to provide objective data on the variability of overlay generation methods and to contribute to the standardization and scientific reliability of forensic dental analyses.
Study design
- Observational model
- Case only
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Participants undergoing digital dental model analysis | – | Other: 3D Digital Model Overlay AnalysisSingle cohort of adult participants undergoing a single intraoral digital scan. Digital models are subsequently analysed by four independent operators at two separate time points (T1 and T2) to assess intra- and inter-operator reproducibility. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Adult participants recruited among patients attending a dental clinic for routine care requiring intraoral optical scanning.
Key inclusion criteria (4 listed)
- Age ≥18 years
- Patients requiring dental care including intraoral optical scan
- Able to understand the study and provide informed consent
- Sufficient dentition allowing usable maxillary scan
Key exclusion criteria (6 listed)
- Age <18 years
- Individuals under legal protection (guardianship or curatorship)
- Oral conditions preventing intraoral scanning
- Refusal to participate
- Completely edentulous patients
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| 3D Digital Model Overlay AnalysisStandardized overlay protocol applied to digital dental models (STL/PLY files). Each model is analysed twice by each of four operators at two separate time points (T1 and T2) to assess intra- and inter-operator reproducibility. | Other | Participants undergoing digital dental model analysis |
Primary outcome
Intra-operator Reproducibility of Overlay Concordance Measurements
Time frame: Baseline and Day 7 (±2 days)
Agreement between repeated overlay analyses performed by the same operator on the same digital maxillary model across two measurement sessions
4 secondary outcomes
Inter-operator Reproducibility of Overlay Concordance Measurements
Time frame: Baseline and Day 7 (±2 days)
Distance Between Point Clouds in 3D Overlay Analysis
Time frame: Baseline and Day 7 (±2 days)
Surface Overlap in Digital Overlay Analysis
Time frame: Baseline and Day 7 (±2 days)
Influence of Operator Expertise on Overlay Reproducibility
Time frame: Baseline and Day 7 (±2 days)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 24 Jun 2026.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Forensic Dentistry and Bite Mark Analysis, run by Nantes University Hospital at 1 site in France.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 24 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in France. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Lise Malfroy-Camine, MD, PhD (+33 6 76 87 10 79, lise.malfroy@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Intra-operator Reproducibility of Overlay Concordance Measurements (time frame: Baseline and Day 7 (±2 days)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 24 Jun 2026.