An observational study in Peri Implant Mucositis, Peri Implant Bone Loss and Peri Implantitis, sponsored by University of Barcelona. Active, not recruiting at 1 site in Spain. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-08-31.
Sponsored by University of Barcelona · Observational
Introduction: Dental implants offer a durable, aesthetic, and functional option for tooth replacement. However, they are not immune to failure. Current literature has highlighted the importance of systemic factors (such as vitamin D deficiency, osteoporosis and hypercolesterolemia) and local factors (such as the presence of nearby periapical infections or implant placement in sites with a history of endodontic failure) that affect bone health.
Hypothesis: Bone alterations-whether systemic or local-represent a risk factor for implant failure and peri-implantitis.
Objectives: To analyze implant failure and marginal bone loss in patients with local and/or systemic bone alterations compared to patients without such conditions.
Methods: Implant failures occurring in patients treated within the Master's Program in Oral Medicine, Surgery, and Implantology at the University of Barcelona (MCIO-UB) over the last 10 years will be analyzed and correlated with bone factors (local and systemic) recorded in their medical histories. Cases lacking the radiographic and clinical data necessary to conduct the study will be excluded.
Population: A total of 3,500 implants have been placed, with failure rates ranging from 4% to 8% depending on the techniques used; consequently, the study sample will consist of 192 implants. Cohorts of successful implants will be established by matching patients of the same sex and within a ±5-year age range who did not experience implant failure.
This is a retrospective cohort study, in which it is intended to reveal the relationship between local and systemic bone conditions and their paper in dental implants failure and peri-implant bone loss.
The sample will be selected from patients who have undergone implant placement at the University of Barcelona Dental Hospital (HOUB).
The inclusion criteria will be:
Patients will be excluded if they fail to meet the inclusion criteria
The sample size will be based on a total of 3,500 implants placed over 10 years and an expected proportion of 0.05, the calculated sample size is 192 implants. Although this is a retrospective study, the aim is to obtain the maximum number of cases, with a minimum of 50. Considering that the rate of peri-implantitis in implants adjacent to a tooth with periapical pathology can be 31%, compared to 2.8% for those that are not. The minimum sample size for implants with peri-implantitis (Yes/No) would be 36, with a confidence interval of 0.05.
METHODS, TECHNIQUES, TESTS, INTERVENTIONS
Teeth will be evaluated using the Periapical Index (PAI), which categorizes periapical status as follows: 1. Periapical bone destruction almost certainly absent, 2. Periapical bone destruction probably absent, 3. Uncertain, 4. Periapical bone destruction probably present, 5. Periapical bone destruction definitely present. Additionally, the size of the periapical lesion will be measured on periapical radiographs (mesio-distal x corono-apical).
Peri-implantitis will be categorized based on the degree of mesial and distal bone loss around the implants, using the index employed by Monje et al.: Mild: 3-4 mm or \< 25% of implant length. Moderate: 4-5 mm or ≥ 25%-50% of implant length. Advanced: > 6 mm or > 50% of implant length.
The following primary variables will be analyzed:
ITEMS VARIABLES Sex Categorical-dichotomous Age Numerical-continuous
The variables studied regarding the implant analysis will be:
MEASUREMENT VARIABLE TYPE:
Analyzed implant Categorical-polychotomous Type of regeneration Categorical-polychotomous Dimensions of achieved regeneration (in mm) Numerical-continuous Type of material used for regeneration Categorical-polychotomous Measurements of the implant platform-to-bone crest relationship (in mm) Numerical-continuous Measurement of mesial-distal bone loss (in mm) Numerical-continuousTime from implant placement to the radiograph taken to assess bone loss (in months) Continuous numerical Implant failure Dichotomous categorical Time from implant placement to implant failure (in months) Continuous numerical Implant type Polychotomous categorical Prosthesis type Polychotomous categorical
The variables studied regarding the relationship with an endodontically treated tooth will be:
MEASUREMENT VARIABLE TYPE Implant analyzed Polychotomous categorical Distance to the tooth (in mm) Continuous numerical Periapical Index (PAI) Polychotomous categorical Implant site in relation to endodontic failure Dichotomous categorical Periapical lesion dimensions (in mm) Continuous numerical Signs and symptoms of endodontic failure Polychotomous categorical Time since extraction Continuous numerical
The parameters analyzed from blood tests and medical history will be:
VARIABLE VARIABLE TYPE Creatinine Continuous numerical BUN Continuous numerical Glomerular filtration rate Continuous numerical Urea Continuous numerical Calcium Continuous numerical Phosphorus Continuous numericalVitamina D 25 Vitamin D 25 Numerical-continuous PTH Numerical-continuous C-reactive protein Numerical-continuous ESR Numerical-continuous Osteoporosis Categorical-dichotomous Total cholesterol level Numerical (continuous) LDL cholesterol level Numerical (continuous) HDL cholesterol level Numerical (continuous) Triglycerides Numerical (continuous)
In summary, the methodology to be used is as follows:
The sample will be selected from patients who have received dental implants at the University of Barcelona Dental Hospital (HOUB).
Exclusion Criteria:
patients in which dental implants had not been lost since the positioning
patients in which dental implants had been lost since the positioning
Difference in the prevalence of implant failure and peri-implantitis between patients presenting with local and/or systemic alterations involving the bone.
To see the differences of prevalences of all those factors affecting implants in the patients who present a success or failure of dental implants. The measurements that will be used will be all those taking into account local and systemic bone conditions and the final outcome of the implant: failure, bone loss or success.
Time frame: 2013-2026
Relationship of osteoporosis and implant failure
Differences in prevalence of osteoporosis of those patients who present implant failure and success. The measurements that will be taken will be: Osteoporosis Categorical (dichotomous), compared to Mesial-distal bone loss measurement (mm) Numerical (continuous). Time from implant placement to radiographic of bone loss (months) Numerical (continuous). Implant failure Categorical (dichotomous). Time from implant placement to implant failure (months) Numerical (continuous). All previous data will be useful to see if there is a correlation between osteoporosis and the other variables.
Time frame: 2013-2026
Relationship of vitamine D levels and implant failure
Differences in prevalence of deficient or insufficient vitamin D levels of those patients who present implant failure and success. The measurements that will be taken will be: 25-Hydroxyvitamin D (25(OH)D) level Numerical (continuous) compared to Mesial-distal bone loss measurement (mm) Numerical (continuous). Time from implant placement to radiographic of bone loss (months) Numerical (continuous). Implant failure Categorical (dichotomous). Time from implant placement to implant failure (months) Numerical (continuous). All previous data will be useful to see if there is a correlation between vitamine D levels and the other variables.
Time frame: 2013-2026
Relationship between dental implant failure and dental failure
Differences in prevalence of recent dental failure of those patients who present implant failure and success, in which the implant was located in the position of the dental failure. The measurements that will be taken will be: Time from insertion to failure/last radiographic revision Numerical (continuous). Mesial-distal bone loss measurement (mm) Numerical (continuous). Time from implant placement to radiographic of bone loss (months) Numerical (continuous). Implant failure Categorical (dichotomous). Time from implant placement to implant failure (months) Numerical (continuous). All the previous data will be compared to : Implant site in relation to a previous endodontic failure Categorical (dichotomous). Time since tooth extraction Numerical (continuous). Signs and symptoms of endodontic failure Categorical (polychotomous). The statistical correlation will be analysed.
Time frame: 2013-2026
Relationship between the presence of an adjacent endodontically treated tooth and implant failure
Differences in prevalence of implant failure in those patients presenting an adjacent endodontically treated tooth. The measurements that will be taken will be: Time from insertion to failure/last radiographic revision Numerical (continuous). Implant platform-to-bone crest relationship measurements (mm) Numerical (continuous). Mesial-distal bone loss measurement (mm) Numerical (continuous). Time from implant placement to radiographic of bone loss (months) Numerical (continuous). Implant failure Categorical (dichotomous). Time from implant placement to implant failure (months) Numerical (continuous). Previous variables will be compared to: Tooth or teeth adjacent to implants Categorical (polychotomous).Distance of the implant to the tooth (mm) Numerical (continuous).Periapical Index (PAI) Categorical (polychotomous). Dimensions of the periapical lesion (mm) Numerical (continuous). That comparison will make it possible to determine if there is a statistical correlation.
Time frame: 2013-2026
Paper of dental prosthesis in implant failure
Showing the relationship between dental prosthesis over implants and the failure of them. The measurements that will be taken will be: Implant failure Categorical (dichotomous) and Bone loss around implants Numerical (continuous) will be compared to see the correlations with: Type of prothesis Categorical (polychotomous)..Number of crowns splinted Numerical (discrete). Dimensions of the cantilever, if existing, in mm (horizontal and vertical) Numerical (continuous). Dimension of the abutment in mm (mesio-distal) Numerical (continuous) Dimension of the implant platform in mm Numerical (continuous) Angle of the implant platform with the abutment (mesial and distal) Numerical (continuous). Angle of the axial axis of the implant with the outermost point of the crown (mesial and distal) in single crowns Numerical (continuous).Gap between the implant platform and the abutment (if present) in mm, measured in mesial, central and distal points Numerical (continuous)
Time frame: 2013-2026
Documents are hosted by the registry — open the source record to download them.
Plan to share: No — The participant data will be anonymized for all those researchers not collaborating in the study
This study is active, not recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
University of Barcelona