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Peri-implantitisNCT07792499

Effect of Metallic Particles on the Progression of Peri-Implantitis

An observational study of Peri-implantitis, run by University of Barcelona.

Not yet recruiting

Opening soon. The study is approved but enrolment has not started yet. Sites may already take enquiries.

Sites and contacts
Official record
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Trial summary

This observational cross-sectional study aims to investigate the presence and characteristics of metallic micro- and nanoparticles in peri-implant tissues and their potential association with peri-implantitis progression, the local microbiota, and the host inflammatory response. Read more about this study

Who is it for?
Ages 18 years and olderHealthy volunteers can take part
Conditions the study is for
Peri-implantitis
Type of treatment
Pill or oral medicine
How many people
50 participants
Where
No sites listed yet
Study dates
1 Oct 2026to 30 Mar 2028
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
  • Healthy volunteers accepted
  • Adult, Older adult

Study population: Participants will be recruited from patients treated at the Hospital Odontològic Universitat de Barcelona (HOUB), within the Master's Degree in Oral Surgery and Implantology and the Master's Degree in Periodontology and Peri-Implantology. The Peri-implantitis Group will include patients diagnosed with peri-implantitis referred for treatment, while the Control Group will include partially or fully edentulous patients requiring first-stage surgical placement of at least one dental implant.

Inclusion Criteria: To be considered eligible for participation in this study, patients must fulfil all the following criteria:

  1. Written informed consent duly completed and signed for participation in the study and the use of biological samples.
  2. Male or female patients aged 18 years or older.
  3. Patients treated at the Master's Degree in Oral Surgery and Implantology or the Master's Degree in Periodontology and Peri-Implantology at the University of Barcelona.
  4. Patients in full possession of their mental faculties and capable of understanding and providing written informed consent prior to enrolment in the study.
  5. Willingness to comply with all study procedures required by the protocol. In addition, participants must meet the criteria for one of the following study groups:
  • Peri-implantitis Group:
  1. Diagnosis of peri-implantitis according to the diagnostic criteria established at the 2017 World Workshop on the Classification of Periodontal and Peri- Implant Diseases and Conditions.
  2. Candidate for surgical or non-surgical peri-implantitis treatment involving the collection of peri-implant granulation tissue and/or biofilm samples.
  • Control Group:
  1. Candidate for implant therapy, with the placement of at least one dental implant included in the treatment plan.
  2. Candidate for implant placement using a static computer-guided surgical approach.
  3. Availability of soft tissue from the implant recipient site for sample collection (≥ 3 mm).

Exclusion Criteria: To be considered eligible for participation in this study, patients must not fulfil any of the following criteria:

  1. Patients who, in the investigator's judgement, are not suitable candidates for participation in the study based on their medical history, physical examination findings, concomitant medications, or concurrent systemic conditions:
  2. Presence of uncontrolled periodontal disease, defined as probing depths ≥5 mm with concomitant bleeding on probing or probing depths ≥6 mm.
  3. Immunocompromised patients.
  4. History of radiotherapy or chemotherapy.
  5. Presence of uncontrolled systemic diseases.
  6. Presence of systemic conditions known to affect bone metabolism.
  7. Current treatment with medications known to alter bone metabolism.
  8. History of oral cancer.
  9. Use of systemic antibiotics within the previous 6 months.
  10. Current smokers consuming ≥20 cigarettes per day.
  11. History of drug or alcohol abuse. For the purposes of this study, alcohol abuse is defined as the habitual consumption of more than four units of alcohol per day (one unit being approximately equivalent to 125 mL of wine, 200 mL of beer, or 25 mL of spirits).
  12. Participation in any other clinical study within the 4 weeks preceding enrolment.
  13. Surgical or non-surgical peri-implantitis treatment at the selected implant site within the 12 months preceding enrolment.
  14. Pregnant or breastfeeding women.

Trial locations and contacts

No sites are listed yet. Contact the study team or a site near you to ask about taking part.

Octavi Camps Font, DDS MS PhD contact

+34 934 024 269

ocamps@ub.edu

About this study

Official title: Effect of Metallic Micro- and Nanoparticles on the Progression of Peri-Implantitis and Their Interaction With the Microbiota

This observational cross-sectional study aims to investigate the presence and characteristics of metallic micro- and nanoparticles in peri-implant tissues and their potential association with peri-implantitis progression, the local microbiota, and the host inflammatory response.

The study will include 50 participants divided into two groups: individuals requiring dental implant placement, from whom healthy gingival tissue will be collected as an active control, and patients diagnosed with peri-implantitis, from whom granulation tissue and submucosal biofilm samples will be obtained. Tissue samples will be analysed to determine the concentration, size, morphology, and intracellular localisation of metallic particles, as well as macrophage polarisation. Microbiological analyses will characterise the peri-implant microbiota. Associations between metallic particle burden, microbiological composition, inflammatory response, and clinical and radiographic indicators of peri-implant disease severity and progression will also be explored.

Read the detailed description

This observational cross-sectional study will include 50 participants, with one study site per participant, divided equally into two groups. The active control group will include patients requiring the placement of at least one dental implant. A healthy gingival tissue sample will be collected immediately before implant placement, provided that the width of keratinised mucosa at the sampling site is at least 3 mm. The peri-implantitis group will include patients diagnosed according to the 2017 World Workshop case definition. Granulation tissue and a submucosal biofilm sample will be collected from the selected affected implant. Participants will not be assigned to any exposure or therapeutic intervention for research purposes.

Tissue samples from both groups will be divided into subsamples and analysed using complementary laboratory techniques. Inductively coupled plasma triple quadrupole mass spectrometry will be used to quantify titanium, aluminium, vanadium, molybdenum, and chromium. Scanning and transmission electron microscopy will be used to characterise the size, morphology, distribution, and intracellular localisation of metallic particles. Histopathological and immunohistochemical analyses will evaluate tissue characteristics and macrophage polarisation.

In the peri-implantitis group, 16S ribosomal RNA gene sequencing of submucosal biofilm samples will be performed to characterise the microbial community. A biofilm sample will not be collected from the active control group because these participants do not yet have an established peri-implantitis environment at the sampling site.

Clinical, radiographic, implant-related, prosthetic, and participant-related variables will also be recorded. The study will compare the metallic particle burden and tissue characteristics between healthy gingival and peri-implantitis tissues. It will also explore associations between metallic particle burden, microbial composition, macrophage polarisation, and clinical and radiographic indicators of peri-implant disease severity and progression.

Keywords
Peri-implantitis, Dental implants, Metallic micro- and nanoparticles, Titanium particles, Peri-implant microbiota, Submucosal biofilm, Granulation tissue, Macrophage polarization
Medical subject headings
Peri-Implantitis

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

Study groups in NCT07792499
Study groupRoleWhat they receive
Peri-implantitisInclusion Criteria Adult patients (≥18 years old) diagnosed with peri-implantitis according to the definition established by the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions (Berglundh et al., 2018). Implants presenting bleeding on probing and/or suppuration, increased probing depth, and progressive bone loss compared with previous records. When previous records are unavailable, implants will be included if they present bleeding and/or suppuration on gentle probing, probing depth ≥ 6 mm, and a bone level ≥ 3 mm apical to the most coronal portion of the implant's rough surface.
Control: prior to implant placementTo be considered eligible for participation in this study, patients must fulfil all the following criteria: 1. Written informed consent duly completed and signed for participation in the study and the use of biological samples. 2. Male or female adult patients. 3. Patients treated at the Master's Degree in Oral Surgery and Implantology or the Master's Degree in Periodontology and Peri-Implantology at the University of Barcelona. 4. Patients in full possession of their mental faculties and capable of understanding and providing written informed consent. 5. Willingness to comply with all study procedures. In addition, participants must meet the criteria for being part of the control group: 1. Candidate for implant therapy, with the placement of at least one dental implant included in the treatment plan. 2. Candidate for implant placement using a static computer-guided surgical approach. 3. Availability of soft tissue from the implant recipient site for sample collection (≥ 3 mm).

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Concentration of metallic elements (Ti, Al, V, Mo and Cr) in tissue samples (ppb).

    The concentrations of titanium (Ti), aluminium (Al), vanadium (V), molybdenum (Mo), and chromium (Cr) will be quantified separately in healthy gingival tissue and peri-implant granulation tissue using inductively coupled plasma triple quadrupole mass spectrometry (ICP-TQ-MS). The concentration of each metallic element will be reported in parts per billion (ppb) and compared between the active control and peri-implantitis groups. Unit of Measure: Parts per billion (ppb).

    Measured: Day 1

Secondary outcomes (8)
  1. Microbial species richness and evenness within each sample (alpha diversity).

    Alpha diversity of the submucosal microbiome will be assessed in biofilm samples collected from the peri-implant site with the greatest probing depth in participants with peri-implantitis. Bacterial DNA will be extracted and the microbiome characterised by 16S ribosomal RNA gene sequencing. Alpha diversity will describe microbial richness, defined as the number of microbial taxa detected within each sample, and evenness, defined as how uniformly their relative abundances are distributed. Results will be reported as alpha-diversity index values.

    Measured: Day 1

  2. Microbial composition between samples from different clinical conditions (beta diversity).

    Beta diversity of the submucosal microbiome will be assessed in biofilm samples collected from participants with peri-implantitis. Bacterial DNA will be extracted and the microbiome characterised by 16S ribosomal RNA gene sequencing. Beta diversity will quantify the degree of similarity or dissimilarity in the identity and relative abundance of microbial taxa between samples. These comparisons will be used to evaluate whether microbial community composition varies according to metallic particle concentration and the clinical characteristics of the sampled peri-implant sites. Results will be reported as beta-diversity distance values.

    Measured: Day 1

  3. Percentage of TiO₂ Nanoparticles in Each Morphological Category

    Titanium dioxide (TiO₂) nanoparticles will be evaluated in healthy gingival tissue from the active control group and peri-implant granulation tissue from the peri-implantitis group. High-resolution transmission electron microscopy (TEM) will be used to visualise the particles, and energy-dispersive X-ray spectroscopy (EDS/EDX) will confirm their elemental composition. Nanoparticles will be classified according to their observed shape and structural features. The percentage of identified TiO₂ nanoparticles in each morphological category will be reported for each sample. Unit of measure: %.

    Measured: Day 1

  4. Mean Diameter of TiO₂ Nanoparticles

    Titanium dioxide (TiO₂) nanoparticles will be evaluated in healthy gingival tissue from the active control group and peri-implant granulation tissue from the peri-implantitis group. High-resolution transmission electron microscopy (TEM) will be used to visualise the particles, and energy-dispersive X-ray spectroscopy (EDS/EDX) will confirm their elemental composition. Particle diameters will be measured using ImageJ image-analysis software, and the mean diameter of the identified TiO₂ nanoparticles in each sample will be reported in nanometres (Unit of Measure: nm).

    Measured: Day 1

  5. Intracellular distribution of TiO₂ nanoparticles.

    The intracellular presence and localisation of titanium dioxide (TiO₂) nanoparticles will be evaluated in cells isolated from healthy gingival tissue and peri-implant granulation tissue. Ultrathin tissue sections will be examined using high-resolution transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDS/EDX) will be used to confirm the elemental composition of the identified particles. The analysis will describe whether TiO₂ nanoparticles are located within cells and their distribution and interaction with intracellular structures.

    Measured: Day 1

  6. Rate of peri-implant bone loss progression (mm/year)

    In participants with peri-implantitis, peri-implant bone loss will be measured radiographically in millimetres at the time of biological sample collection. The estimated average annual rate of bone loss will be calculated by dividing the radiographic bone loss by the time elapsed, in years, from implant placement to sample collection. Higher values indicate a faster estimated rate of peri-implant bone loss. Results will be reported in millimetres per year (mm/year).

    Measured: Day 1

  7. Macrophage polarisation (M1 versus M2 phenotype)

    Macrophage polarisation will be assessed in healthy gingival tissue from the active control group and peri-implant granulation tissue from the peri-implantitis group. Paraffin-embedded tissue sections will undergo immunohistochemical analysis using established markers for pro-inflammatory M1 and anti-inflammatory and tissue-repair-associated M2 macrophage phenotypes. The relative distribution of both macrophage populations will be quantified and reported as the M1/M2 ratio. A higher ratio indicates a relative predominance of the pro-inflammatory M1 phenotype.

    Measured: Day 1

  8. Number of TiO₂ Nanoparticles per Tissue Sample

    Titanium dioxide (TiO₂) nanoparticles will be evaluated in healthy gingival tissue from the active control group and peri-implant granulation tissue from the peri-implantitis group. High-resolution transmission electron microscopy (TEM) will be used to visualise the particles, and energy-dispersive X-ray spectroscopy (EDS/EDX) will confirm their elemental composition. The number of identified TiO₂ nanoparticles in each tissue sample will be quantified using ImageJ image-analysis software and reported as the number of nanoparticles per sample.

    Measured: Day 1

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted28 Aug 2026
  2. Study start1 Oct 2026 (estimated)
  3. Primary completion3 Sep 2027 (estimated)
  4. Study completion30 Mar 2028 (estimated)

Resources

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
Other
Time perspective
Cross-sectional
Enrolment
50 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT07792499
Sponsor's protocol ID
14/2025
Status last verified
Aug 2026
First submitted
20 Aug 2026
Last updated
28 Aug 2026
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No

Questions about this trial

What is this clinical trial studying?

An observational study of Peri-implantitis, run by University of Barcelona.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

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: opening soon, as of the sponsor's last update on 28 Aug 2026. Status can change between updates, so confirm with the study contact before making plans.

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 Octavi Camps Font, DDS MS PhD (+34 934 024 269, ocamps@ub.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Concentration of metallic elements (Ti, Al, V, Mo and Cr) in tissue samples (ppb). (time frame: Day 1). 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 28 Aug 2026.

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