EdentulismIMPROSTREHABNCT07639112
Masticatory Efficiency, Bite Force, and Patient-Reported Outcomes in Patients Rehabilitated With Complete and Partial Dentures Supported by Teeth, Mini-Implants, or Conventional Implants
An observational study of Edentulism and Edentulism Complete, run by University of Zagreb at 2 sites in Croatia.
Trial summary
This study aims to evaluate masticatory efficiency, bite force, and patient-reported outcomes in edentulous and partially edentulous patients rehabilitated with different removable prosthodontic treatment modalities. The study includes both cross-sectional and longitudinal components. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Edentulism, Edentulism Complete, Partial Edentulism
- How many people
- 240 participants
- Where
- 2 sitesCroatia
- Study dates
- 14 Jun 2025to Sep 2027
- Phase
- Observational
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: The study population will comprise edentulous and partially edentulous adult patients treated at the Department of Prosthodontics, University of Zagreb School of Dental Medicine. Participants will include wearers of conventional complete dentures, conventional removable partial dentures, mini-implant-retained overdentures, conventional implant-retained overdentures, mini-implant-assisted removable partial dentures, and implant-assisted removable partial dentures. Additional participants undergoing prosthodontic rehabilitation will be prospectively recruited for the longitudinal component of the study.
Who may be able to join
- Age 18 years or older.
- Ability to understand the study procedures and provide written informed consent.
- Wearing the respective prosthodontic restoration for at least 6 months (cross-sectional component).
- Planned rehabilitation with one of the investigated prosthodontic treatment modalities (longitudinal component).
- Ability to perform masticatory tests and complete questionnaires.
Who cannot join
- Severe cognitive impairment or inability to complete questionnaires.
- Neurological or muscular disorders affecting mastication.
- Acute oral infections or untreated oral pathology.
- Severe temporomandibular disorders causing pain or functional limitation.
- Implant or prosthesis failure requiring immediate treatment.
- Any medical condition that, in the opinion of the investigators, could affect study participation or outcome assessment.
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Trial locations and contacts
2 sites in 1 country.
Croatia2 sites
School of Dental Medicine, University of Zagreb
Zagreb, City of Zagreb, 10000
School of Dental Medicine, University of Zagreb
Zagreb, 10000
About this study
Official title: Masticatory Efficiency, Bite Force, and Patient-Reported Outcomes in Patients Rehabilitated With Conventional Complete Dentures, Conventional Removable Partial Dentures, Mini-Implant-Retained Overdentures, Conventional Implant-Retained Overdentures, and Implant-Assisted Removable Partial Dentures: A Cross-Sectional and Longitudinal Clinical Study
This study aims to evaluate masticatory efficiency, bite force, and patient-reported outcomes in edentulous and partially edentulous patients rehabilitated with different removable prosthodontic treatment modalities. The study includes both cross-sectional and longitudinal components. The cross-sectional component will compare patients wearing conventional complete dentures, conventional removable partial dentures, mini-implant-retained overdentures, conventional implant-retained overdentures, and implant-assisted removable partial dentures. The longitudinal component will assess changes in masticatory performance, bite force, and patient-reported outcomes following prosthodontic rehabilitation and adaptation over time.
The study seeks to determine whether implant-assisted treatment options provide superior functional outcomes, oral health-related quality of life, and patient satisfaction compared with conventional removable prostheses.
Read the detailed description
Tooth loss and edentulism are associated with impaired masticatory function, reduced bite force, compromised oral function, and decreased oral health-related quality of life. Conventional complete dentures and removable partial dentures remain widely used treatment modalities; however, limitations in retention, stability, and chewing efficiency may negatively affect patient satisfaction and functional outcomes. Implant-assisted treatment concepts, including mini-implant-retained overdentures, conventional implant-retained overdentures, and implant-assisted removable partial dentures, have been introduced to improve prosthesis retention, stability, comfort, and oral function.
The IMPROSTREHAB study (Implant and Prosthodontic Rehabilitation Outcomes Study) is an observational clinical study designed to evaluate functional and patient-reported outcomes associated with different removable prosthodontic treatment modalities in edentulous and partially edentulous patients.
The study comprises both cross-sectional and longitudinal components. In the cross-sectional component, masticatory efficiency, bite force, oral health-related quality of life, and patient-reported outcomes will be compared among individuals rehabilitated with conventional complete dentures (CDs), conventional removable partial dentures (RPDs), mini-implant-retained overdentures (MDI-ODs), conventional implant-retained overdentures (CI-ODs), and implant-assisted removable partial dentures (IARPDs). Additional analyses will evaluate the influence of demographic, clinical, anatomical, and prosthodontic factors, including age, sex, duration of prosthesis use, residual ridge resorption, number and distribution of remaining teeth, implant-related variables, and other factors that may influence treatment outcomes.
In the longitudinal component, participants receiving new prosthodontic treatment will be followed prospectively to assess changes in masticatory function, bite force, oral health-related quality of life, and patient-reported outcomes following treatment and adaptation to the prosthesis. Repeated assessments will be performed at predefined follow-up intervals according to the specific objectives of individual study subprojects.
Masticatory performance and masticatory efficiency will be evaluated using validated and standardized assessment methods, including chewing-gum mixing ability tests and other objective functional measures where appropriate. Maximum bite force will be assessed using calibrated bite-force measurement devices. Patient-reported outcomes will be evaluated using validated questionnaires and instruments, including measures of oral health-related quality of life, self-perceived chewing ability, denture satisfaction, treatment satisfaction, esthetic outcomes, and other patient-centered outcomes.
The primary objective of the study is to evaluate and compare masticatory efficiency and functional performance among different conventional and implant-assisted removable prosthodontic treatment modalities. Secondary objectives include the assessment of maximum bite force, oral health-related quality of life, chewing ability, patient satisfaction, esthetic outcomes, and other patient-reported outcomes, as well as the identification of factors associated with favorable functional and patient-centered treatment outcomes.
Participants will be recruited from the University of Zagreb School of Dental Medicine and affiliated clinical settings. Treatment allocation is not determined by the investigators but reflects routine clinical care and previously completed prosthodontic rehabilitation. The results of this study are expected to improve understanding of the functional and patient-centered benefits of contemporary removable prosthodontic treatment options and to support evidence-based clinical decision-making for edentulous and partially edentulous patients.
- Conditions
- Edentulism, Edentulism Complete, Partial Edentulism, Complete Dentures, Removable Partial Denture, Implant Supported Overdenture
- Keywords
- mini dental implants, Masticatory Efficiency, Bite Force, OHIP, Chewing Function Questionnaire, Patient-Reported Outcomes, Oral Health-Related Quality of Life, Complete Denture, Removable Partial Denture, Implant-Retained Overdenture, Implant-Assisted Removable Partial Denture, Implant overdenture, Edentulous Patients, Partially Edentulous Patients, Prosthodontic Rehabilitation, Chewing Ability, Orofacial Esthetics
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Conventional Complete Dentures (CD) | Edentulous participants rehabilitated with conventional maxillary and mandibular complete dentures. | |
| Two Standard Implant Overdentures (2-IOD) | Edentulous participants rehabilitated with mandibular overdentures retained by two conventional dental implants and opposed by maxillary complete dentures. | |
| Four Mini-Implant Overdentures (4-MDI-OD) | Edentulous participants rehabilitated with mandibular overdentures retained by four mini dental implants and opposed by maxillary complete dentures. | |
| Conventional Removable Partial Dentures (RPD) | Partially edentulous participants rehabilitated with conventional removable partial dentures. | |
| Mini-Implant-Assisted RPD (MDI-RPD) | Partially edentulous participants rehabilitated with removable partial dentures assisted by mini dental implants. | |
| Implant-Assisted RPD (IARPD) | Partially edentulous participants rehabilitated with removable partial dentures assisted by conventional dental implants. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Masticatory Efficiency
Assessment of masticatory efficiency using a standardized two-color chewing-gum mixing ability test. The degree of color mixing will be quantified using digital image analysis.
Measured: Cross-sectional component: at study enrollment. Longitudinal component: baseline (before treatment), prosthesis delivery, 3 months, and 12 months after treatment.
Secondary outcomes (6)
Maximum Bite Force
Maximum voluntary bite force measured in Newtons (N) using a calibrated bite-force measurement device.
Measured: At study enrollment; baseline, prosthesis delivery, 3 months, and 12 months after treatment.
Oral Health-Related Quality of Life (OHIP)
Oral Health Impact Profile questionnaire score.
Measured: At study enrollment; baseline, 3 months, and 12 months after treatment.
Self-Perceived Chewing Function (CFQ)
Chewing Function Questionnaire score.
Measured: At study enrollment; baseline, 3 months, and 12 months after treatment.
Orofacial Esthetics (OES)
Orofacial Esthetic Scale score.
Measured: At study enrollment; baseline, 3 months, and 12 months after treatment.
Residual Ridge Morphology
Assessment of residual alveolar ridge morphology using the Cawood and Howell classification.
Measured: At study enrollment and baseline before treatment.
Assessment of denture retention using the Modified Kapur Index.
Clinical assessment of denture retention and stability using the Modified Kapur Index. Retention and stability scores will be recorded according to standardized clinical criteria, with higher scores indicating improved prosthesis retention and stability.
Measured: Cross-sectional component: at study enrollment. Longitudinal component: prosthesis delivery, 3 months, and 12 months after treatment.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted10 Jun 2026
- Study start14 Jun 2025
- Primary completionMay 2027 (estimated)
- Study completionSep 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for EdentulismStudies 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
- Cohort
- Time perspective
- Other
- Enrolment
- 240 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Zagreb
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Sanja Persic Kirsic, University of Zagreb
- Investigators
- Sanja Persic Kirsic, Phd, Associate Professor, Principal investigator, School of Dental Medicine University of ZagrebSanja Persic Kirsic, Principal investigator, School of Dental Medicine University of Zagreb
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07639112
- Sponsor's protocol ID
- SFZG-PROS-IMPL2026
- Other IDs
- SFZG-06-2025 (INOVA-Dent-KPI)
- Acronym
- IMPROSTREHAB
- Status last verified
- Jun 2026
- First submitted
- 5 Jun 2026
- Last updated
- 10 Jun 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No