Overview

This trial is active, not recruiting.

Conditions tooth-loss, edentulous mouth, complete denture, complete lower denture
Treatments 1 implant placed surgically in the mandibular midline, 2 implants placed surgically in the mandibular canine sites, soft reline (coe comfort) of the existing complete lower denture, 2.25mm ball patrix placed on 1 healed implant, 2.25mm ball patrices placed on 2 healed implants, reline (ivoclar acrylic-resin) with 1 retentive matrix in the lower denture, reline (ivoclar acrylic-resin) with 2 retentive matrices in the lower denture
Sponsor University of British Columbia
Collaborator ITI International Team for Implantology Foundation
Start date November 2002
End date June 2017
Trial size 86 participants
Trial identifier NCT02117856, H02-70082

Summary

This study is a randomized clinical trial to compare patient satisfaction and prosthetic outcomes with lower dentures retained by one or two implants. The investigators long-term objective is to establish evidence of the cost-effectiveness of a single implant intervention for improving tolerance to complete dentures. The investigators MAIN AIM will be to investigate patient satisfaction between and within groups with mandibular dentures retained by one or two implants over five years, and SECONDARILY to investigate the survival of implants, and the frequency of events to maintain the dentures and prosthetic attachments as clinically serviceable. Furthermore, multivariate analysis can assess the prediction of patient satisfaction with implant dentures based on various possible factors including age, health, demography and socioeconomic status, number of implants, and maintenance needs. Patient satisfaction will be measured by means of Visual Analogue Scales (VAS) including a measure of overall satisfaction and various specific aspects of satisfaction such as appearance, stability and comfort of the dentures.

The CENTRAL HYPOTHESIS is that mandibular complete dentures retained by single implants are at least as satisfying to patients over a five years period as those retained by two implants for the same period.

The SECONDARY HYPOTHESES are that:

i) there is no difference over five years between groups in the survival of original implants, or in the number of events for maintenance of the dentures or implant attachments; and ii) using each treatment group as it's own control, there is no change in patient satisfaction with lower dentures retained by either one or two implants during the five year loading period.

United States No locations recruiting
Other Countries No locations recruiting

Study Design

Allocation randomized
Endpoint classification efficacy study
Intervention model parallel assignment
Masking open label
Primary purpose treatment
Arm
(Active Comparator)
Participants receive the following: 1 implant placed surgically in the mandibular midline; Soft reline of the existing complete lower denture; 2.25mm ball patrix placed on 1 healed implant; and Reline with 1 retentive matrix in the lower denture.
1 implant placed surgically in the mandibular midline Implant is Solid Screw, SLA surface, Straumann Canada
Participants receive an implant in the mandibular midline using a surgical flap procedure with local anaesthesia.
soft reline (coe comfort) of the existing complete lower denture Soft reline is Coe Comfort, GC Corporation
Participants receive a soft reline of the existing complete lower denture approximately 10 days after placement of the implant(s).
2.25mm ball patrix placed on 1 healed implant Patrix is Spherical Stud Retentive Anchor, Straumann Canada
A 2.25mm ball patrix is screwed onto the 1 implant approximately six weeks after placement of the implant.
reline (ivoclar acrylic-resin) with 1 retentive matrix in the lower denture Reline is Ivoclar acrylic-resin, Ivoclar Vivaent Inc, Canada
Participants have their complete lower denture relined with a laboratory-processed acrylic resin to incorporate 1 retentive matrix in the denture-base to retain on the implant.
(Active Comparator)
Participants receive the following: 2 implants placed surgically in the mandibular canine sites; Soft reline of the existing complete lower denture; 2.25mm ball patrices placed on 2 healed implants; and Reline with 2 retentive matrices in the lower denture.
2 implants placed surgically in the mandibular canine sites Implants are Solid Screw, SLA surface, Straumann Canada
Participants receive implants bilaterally in the site of the mandibular canines using a surgical flap procedure with local anaesthesia.
soft reline (coe comfort) of the existing complete lower denture Soft reline is Coe Comfort, GC Corporation
Participants receive a soft reline of the existing complete lower denture approximately 10 days after placement of the implant(s).
2.25mm ball patrices placed on 2 healed implants Patrix is Spherical Stud Retentive Anchor, Straumann Canada
2.25mm ball patrices are screwed onto the 2 implants approximately six weeks after placement of the implants.
reline (ivoclar acrylic-resin) with 2 retentive matrices in the lower denture Reline is Ivoclar acrylic-resin, Ivoclar Vivaent Inc, Canada
Participants have their complete lower denture relined with a laboratory-processed acrylic resin to incorporate 2 retentive matrices in the denture-base to retain on the implants

Primary Outcomes

Measure
Self-assessed VAS satisfaction with the mandibular denture
time frame: Annually during 10 years after attaching the mandibular implant denture

Secondary Outcomes

Measure
Change in self-assessed VAS satisfaction with the mandibular denture
time frame: From baseline (before implants) to each annual followup for 10 years after attaching the mandibular implant denture
Cumulative Implant Survival
time frame: During the 10 years after attaching the mandibular implant denture
The frequency of prosthetic maintenance events for the mandibular implant overdenture
time frame: During 10 years after attaching the mandibular implant denture
Time to provide the initial surgical and prosthetic treatment for the mandibular implant overdenture intervention
time frame: From baseline (before implants) until attachment of the mandibular implant denture, 6 weeks after implant placement
Costs to provide the initial surgical and prosthetic treatment for the mandibular implant overdenture intervention
time frame: From baseline (before implants) until attachment of the mandibular implant denture, 6 weeks after implant placement
Time to provide prosthetic maintenance treatment for the mandibular implant overdenture
time frame: During 1 year after attachment of the mandibular implant denture
Costs to provide prosthetic maintenance treatment for the mandibular implant overdenture
time frame: During 1 year after attachment of the mandibular implant denture

Eligibility Criteria

Male or female participants at least 18 years old.

Inclusion Criteria: - functional in English or accompanied by a responsible adult who can provide translation services - able to consent to, and participate in, the treatment provided - available for the duration of the study - edentulous and with at least six month's experience with conventional complete dentures - currently wearing conventional complete dentures that are esthetically satisfactory to the patient and technically acceptable in the judgment of the study prosthodontist(s) - medically/psychologically suitable for implant surgery in the judgment of the study dentists Exclusion Criteria: - insufficient alveolar bone height for implant(s) (< 10 mm) - history of head and neck radiation - systemic or neurological disease, including: American Society of Anesthesiologists (ASA) Class 3 with recently diagnosed severe systemic disease, e.g. recent (within 6 months) myocardial infarction or stroke; risks associated with bacteraemia, e.g. immune compromise, steroids, in-dwelling catheters, stents, prosthetic heart valves, etc.; Type 1 diabetes, pituitary and adrenal insufficiency, and untreated hypothyroidism; chronic granulomatous disease, e.g. tuberculosis and sarcoidosis; bone disease, e.g. histiocytosis X, Paget's disease, fibrous dysplasia; history of congenital or acquired uncontrolled bleeding, e.g. coumadin - previous oral implant treatment - need for additional pre-prosthetic surgery - need for new complete dentures - medically/psychologically unsuitable for surgery in the opinion of the study dentists

Additional Information

Official title A Randomized Clinical Trial Comparing Patient Satisfaction and Prosthetic Outcomes With Mandibular Implant Overdentures Retained by 1 or 2 Implants
Principal investigator Stephen R. Bryant, DDS, PhD
Trial information was received from ClinicalTrials.gov and was last updated in December 2014.
Information provided to ClinicalTrials.gov by University of British Columbia.