Peri-Implant HealthNCT07898956
Plaque and Bleeding on Probing Around Implants Supporting Fixed Full-Arch Dental Prostheses
An observational study of Peri-Implant Health, run by Nicola Alberto Valente, DDS, MS, PhD at 1 site in Italy.
Trial summary
This observational study examines plaque, hard deposits (calculus), and gum bleeding around dental implants supporting fixed full-arch dental prostheses. The main question is whether the time since the prosthesis was last removed or installed is associated with bleeding around the implants. Read more about this study
- Who is it for?
- Any ageHealthy volunteers can take part
- Conditions the study is for
- Peri-Implant Health
- What is being tested?
- Prosthetic Maintenance History
- How many people
- 50 participants
- Where
- 1 siteItaly
- Study dates
- 1 Nov 2026to 31 Jul 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 Any age
- All sexes
- Healthy volunteers accepted
- Child, Adult, Older adult
Study population: The study population consists of patients previously rehabilitated with implant-supported full-arch fixed dental prostheses (Toronto Bridge) in the maxilla, mandible, or both arches, identified through the clinical registry of a dental practice. Patients were included regardless of systemic conditions, smoking habits, or previous implant failures. Clinical and radiographic peri-implant parameters were assessed during a follow-up examination, while information on implant treatment history and professional prosthetic maintenance was retrospectively retrieved from clinical records. Patients without complete follow-up examinations were retained for analyses based on available historical data.
Who may be able to join
- Patients previously rehabilitated with an implant-supported full-arch fixed dental prosthesis (Toronto Bridge) in the maxilla, mandible, or both arches.
- Patients included in the clinical registry of the participating dental practice.
- Availability of clinical records documenting the implant-supported rehabilitation and relevant treatment history.
- Written informed consent for the use of clinical data for research purposes.
Who cannot join
- Patients without a history of implant-supported full-arch fixed prosthetic rehabilitation.
- Patients without sufficient clinical documentation to establish their eligibility.
- Patients who did not provide informed consent for the use of their clinical data.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Italy1 site
AOU Cagliari - Servizio di Odontostomatologia
Cagliari, CA, 09123
Nicola Alberto Valente, DDS, MS, PhD, +393385932069, nicola.valente@unica.it
About this study
Official title: Time Since Prosthesis Removal or Installation and Peri-Implant Clinical Findings in Patients With Implant-Supported Fixed Full-Arch Prostheses: A Cross-Sectional Observational Study
This observational study examines plaque, hard deposits (calculus), and gum bleeding around dental implants supporting fixed full-arch dental prostheses. The main question is whether the time since the prosthesis was last removed or installed is associated with bleeding around the implants. The study also examines associations with plaque, calculus, smoking, diabetes, and use of a water flosser. Participants undergo no treatment assigned by a research protocol. The study combines a single clinical assessment with information from existing dental records. Clinical data from 43 patients with 279 implants are available; eight additional patients identified in the source registry lack clinical measurements and are included only in the selection flow. Associations do not establish that a longer interval causes inflammation.
Read the detailed description
Single-center cross-sectional observational study at Azienda Ospedaliero Universitaria di Cagliari, Cagliari, Italy. The clinical assessments were performed between 4 March and 26 June 2026. Patients had existing fixed implant-supported full-arch prostheses in the maxilla, mandible, or both arches. There was no research-assigned intervention or treatment allocation.
One dental hygienist, calibrated in probing by an experienced periodontist, performed the clinical examinations. Probing was performed at six sites around each implant. The available probing-depth summary is the maximum recorded depth for each patient, rather than a complete site-level dataset. Implant-level findings include bleeding on probing, plaque, calculus, visible mucosal alterations, suppuration, and pain. Plaque and calculus are analyzed both with internal ordinal scores and as presence/absence. The plaque scale is an adaptation of the Mombelli index and is not the original four-category index. Patient-reported general pain and prosthetic function are recorded separately on numerical scales from 0 to 10.
The exposure of interest is the interval from the last documented prosthesis removal or installation to the assessment, expressed in days and analyzed per 90-day increase. This interval is not a measure of the habitual frequency of maintenance visits. When no subsequent removal was documented, the confirmed installation/delivery date is used; the surgical date is used in one case.
Implant-level binary outcomes are assessed using logistic generalized estimating equations with patient-level clustering, an exchangeable working correlation structure, and robust standard errors. The main association model includes time, smoking, and diabetes. Additional exploratory models consider plaque, calculus, and water-flosser use. Patient-level associations use Spearman correlations. Effect estimates are reported with 95% confidence intervals. Multiple-testing adjustments for the secondary family use Benjamini-Hochberg and Holm procedures. Missing clinical outcomes are not imputed. This record is submitted after the clinical data collection and initial analyses.
- Conditions
- Peri-Implant Health
- Being tested
- Prosthetic Maintenance History
- Keywords
- Dental implants, Hybrid prosthesis, Peri-implant health
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Prosthetic Maintenance HistoryOther
Previous rehabilitation with an implant-supported full-arch fixed dental prosthesis (Toronto Bridge), performed as part of routine clinical care. The study involves clinical and radiographic assessment of peri-implant health, prosthetic conditions, and maintenance history. No experimental treatment or intervention is administered as part of the study.
| Study group | Role | What they receive |
|---|---|---|
| Patients with Implant-Supported Full-Arch Fixed Prostheses | Not described Receives: Other: Prosthetic Maintenance History |
What is being measured
The primary outcome is the main question the study is designed to answer.
Prevalence of Peri-Implant Bleeding on Probing (BoP)
Proportion of dental implants presenting bleeding on probing (BoP) during the clinical examination. BoP is recorded as present or absent for each implant and expressed as the percentage of implants exhibiting bleeding among all clinically evaluated implants. The association between BoP prevalence and professional prosthetic maintenance history, particularly the time elapsed since the last prosthesis removal, will be explored.
Measured: Baseline (single assessment).
Secondary outcomes (3)
Peri-Implant Plaque Accumulation
Assessment of plaque accumulation around dental implants during the clinical examination. Plaque is classified into three categories: absent, slight, or abundant. Results are expressed as the percentage of implants in each category. The association between plaque accumulation and professional prosthetic maintenance history, particularly the time elapsed since the last prosthesis removal, will be evaluated.
Measured: Baseline (single assessment).
Peri-Implant Soft Tissue Inflammation
Clinical assessment of peri-implant soft tissue inflammatory conditions. Inflammation is classified into four categories according to clinical severity: healthy tissues, mild inflammation, moderate inflammation, or severe inflammation. Results are expressed as the percentage of implants in each category. The association between inflammatory status and professional prosthetic maintenance history will be investigated.
Measured: Baseline (single assessment).
Peri-Implant Calculus Accumulation
Assessment of calculus deposits around dental implants during the clinical examination. Calculus accumulation is classified into three categories: absent, slight, or abundant. Results are expressed as the percentage of implants in each category. The association between calculus accumulation and professional prosthetic maintenance history will be evaluated.
Measured: Baseline (single assessment).
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Oct 2026
- Study start1 Nov 2026 (estimated)
- Primary completion30 Jun 2027 (estimated)
- Study completion31 Jul 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Peri-Implant HealthStudies 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
- Other
- Time perspective
- Cross-sectional
- Enrolment
- 50 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Nicola Alberto Valente, DDS, MS, PhD
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor-investigator, Nicola Alberto Valente, DDS, MS, PhD, University of Cagliari
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07898956
- Sponsor's protocol ID
- Allon4-maintenance
- Status last verified
- Oct 2026
- First submitted
- 19 Oct 2026
- Last updated
- 27 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 27 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Time Since Prosthesis Removal or Installation and Peri-Implant Clinical Findings in Patients With Implant-Supported Fixed Full-Arch Prostheses: A Cross-Sectional Observational Study
- ClinicalTrials.gov ID
- NCT07898956
- Acronym / sponsor ID
- Allon4-maintenance
- Conditions
- Peri-Implant Health
- Keywords
- Dental implants, Hybrid prosthesis, Peri-implant health
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 50 participants (estimated)
- Lead sponsor
- Nicola Alberto Valente, DDS, MS, PhDUniversity, hospital or other
- Study start
- 1 Nov 2026 (estimated)
- Primary completion
- 30 Jun 2027 (estimated)
- Study completion
- 31 Jul 2027 (estimated)
- First posted
- 27 Oct 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 observational study examines plaque, hard deposits (calculus), and gum bleeding around dental implants supporting fixed full-arch dental prostheses. The main question is whether the time since the prosthesis was last removed or installed is associated with bleeding around the implants. The study also examines associations with plaque, calculus, smoking, diabetes, and use of a water flosser. Participants undergo no treatment assigned by a research protocol. The study combines a single clinical assessment with information from existing dental records. Clinical data from 43 patients with 279 implants are available; eight additional patients identified in the source registry lack clinical measurements and are included only in the selection flow. Associations do not establish that a longer interval causes inflammation.
Detailed description
Single-center cross-sectional observational study at Azienda Ospedaliero Universitaria di Cagliari, Cagliari, Italy. The clinical assessments were performed between 4 March and 26 June 2026. Patients had existing fixed implant-supported full-arch prostheses in the maxilla, mandible, or both arches. There was no research-assigned intervention or treatment allocation.
One dental hygienist, calibrated in probing by an experienced periodontist, performed the clinical examinations. Probing was performed at six sites around each implant. The available probing-depth summary is the maximum recorded depth for each patient, rather than a complete site-level dataset. Implant-level findings include bleeding on probing, plaque, calculus, visible mucosal alterations, suppuration, and pain. Plaque and calculus are analyzed both with internal ordinal scores and as presence/absence. The plaque scale is an adaptation of the Mombelli index and is not the original four-category index. Patient-reported general pain and prosthetic function are recorded separately on numerical scales from 0 to 10.
The exposure of interest is the interval from the last documented prosthesis removal or installation to the assessment, expressed in days and analyzed per 90-day increase. This interval is not a measure of the habitual frequency of maintenance visits. When no subsequent removal was documented, the confirmed installation/delivery date is used; the surgical date is used in one case.
Implant-level binary outcomes are assessed using logistic generalized estimating equations with patient-level clustering, an exchangeable working correlation structure, and robust standard errors. The main association model includes time, smoking, and diabetes. Additional exploratory models consider plaque, calculus, and water-flosser use. Patient-level associations use Spearman correlations. Effect estimates are reported with 95% confidence intervals. Multiple-testing adjustments for the secondary family use Benjamini-Hochberg and Holm procedures. Missing clinical outcomes are not imputed. This record is submitted after the clinical data collection and initial analyses.
Study design
- Observational model
- Other
- Time perspective
- Cross-sectional
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Patients with Implant-Supported Full-Arch Fixed Prostheses | – | Other: Prosthetic Maintenance History |
Who may qualify
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Child, Adult, Older adult
- Study population
- The study population consists of patients previously rehabilitated with implant-supported full-arch fixed dental prostheses (Toronto Bridge) in the maxilla, mandible, or both arches, identified through the clinical registry of a dental practice. Patients were included regardless of systemic conditions, smoking habits, or previous implant failures. Clinical and radiographic peri-implant parameters were assessed during a follow-up examination, while information on implant treatment history and professional prosthetic maintenance was retrospectively retrieved from clinical records. Patients without complete follow-up examinations were retained for analyses based on available historical data.
Key inclusion criteria (4 listed)
- Patients previously rehabilitated with an implant-supported full-arch fixed dental prosthesis (Toronto Bridge) in the maxilla, mandible, or both arches.
- Patients included in the clinical registry of the participating dental practice.
- Availability of clinical records documenting the implant-supported rehabilitation and relevant treatment history.
- Written informed consent for the use of clinical data for research purposes.
Key exclusion criteria (3 listed)
- Patients without a history of implant-supported full-arch fixed prosthetic rehabilitation.
- Patients without sufficient clinical documentation to establish their eligibility.
- Patients who did not provide informed consent for the use of their clinical data.
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 |
|---|---|---|
| Prosthetic Maintenance HistoryPrevious rehabilitation with an implant-supported full-arch fixed dental prosthesis (Toronto Bridge), performed as part of routine clinical care. The study involves clinical and radiographic assessment of peri-implant health, prosthetic conditions, and maintenance history. No experimental treatment or intervention is administered as part of the study. | Other | Patients with Implant-Supported Full-Arch Fixed Prostheses |
Primary outcome
Prevalence of Peri-Implant Bleeding on Probing (BoP)
Time frame: Baseline (single assessment).
Proportion of dental implants presenting bleeding on probing (BoP) during the clinical examination. BoP is recorded as present or absent for each implant and expressed as the percentage of implants exhibiting bleeding among all clinically evaluated implants. The association between BoP prevalence and professional prosthetic maintenance history, particularly the time elapsed since the last prosthesis removal, will be explored.
3 secondary outcomes
Peri-Implant Plaque Accumulation
Time frame: Baseline (single assessment).
Peri-Implant Soft Tissue Inflammation
Time frame: Baseline (single assessment).
Peri-Implant Calculus Accumulation
Time frame: Baseline (single assessment).
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 27 Oct 2026.
- Individual participant dataSharing planned: No
Related trials for Peri-Implant Health
Active, not recruitingObservational study
Influence of Prosthetic Characteristics of Implant-Supported Crowns on Peri-implant Health and Osseointegration: A Comparison Between Digital and Conventional Workflows.
Implant-supported Single Crowns, Osseointegration
Not yet recruitingObservational study
ATR-FTIR and Raman Spectroscopy of Peri-Implant Crevicular Fluid in Peri-Implantitis
Peri-Implantitis
RecruitingObservational study
Investigation of Macrophage Polarization in Peri-implant Health and Peri-implantitis
Peri-implantitis
Not yet recruitingObservational study
Short Versus Standard Dental Implants: Clinical and Biomarker Outcomes
Peri-Implant Mucositis
RecruitingObservational study
Impact of Smoking on Immune Responses in Peri-implant Health and Disease
Peri-Implant Health, Peri Implant Mucositis
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 Peri-Implant Health, run by Nicola Alberto Valente, DDS, MS, PhD at 1 site in Italy.
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 3 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: opening soon, as of the sponsor's last update on 27 Oct 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 Italy. 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 Nicola Alberto Valente, DDS, MS, PhD (+393385932069, nicola.valente@unica.it), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Prevalence of Peri-Implant Bleeding on Probing (BoP) (time frame: Baseline (single assessment).). 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 27 Oct 2026.