Accuracy and Clinical Outcomes of Titanium-zirconium One-piece Mini Implants Using a Partially-guided Surgery for Maxillary Overdentures: a Pilot Prospective Clinical Study
Trial Snapshot
- Phase
- Not Applicable
- Status
- Not yet recruiting
- Enrollment
- 12
- Primary Endpoint
- Implant Survival and Success
Study Overview
Brief Summary
This is a single-center, single-group, prospective clinical trial testing a partially-guided protocol for placement of mini implants overdentures in the edentulous maxilla. Eligible participants will be subjects with an edentulous maxilla, wearing a conventional complete denture. Participants will receive six mini implants (Straumann® Mini Implant System, Institut Straumann AG, Switzerland) for retention of a maxillary overdenture. The six mini implant protocol will be virtually planned for an even distribution of the implants bilaterally, with a minimum of 5 mm distance between contiguous implants. The available lengths of the mini implants are 10, 12, and 14 mm, and the appropriate length will be selected according to the bony anatomical situation. In addition, the distribution and axial position of the mini implants will be planned to achieve the best biomechanical distribution and the most parallel position between implants, perpendicular to the occlusal plane and path of insertion of the prosthesis. The primary outcome will be the accuracy of the implant position using the partially-guided protocol. Assessment of the accuracy of the methods will be based on the measure of the difference between the actual and the planned position of the mini implants, based on the measurement of (1) the global deviations at the coronal and apical regions of the mini implants, (2) the vertical deviation, and (3) the apical angle deviation. Overall impacts of treatment on oral health-related quality of life will be assessed using the Oral Health Impact Profile instrument for edentulous subjects (OHIP-EDENT). Additional outcomes will include implant survival and success rates, incidence of prosthodontic complications and peri-implant measurements.
Detailed Description
Design This is a single-center, single-group, prospective clinical trial testing a partially-guided protocol for placement of mini implants overdentures in the edentulous maxilla.
Study setting, trial registration, and funding This clinical trial will be conducted in the clinical setting of the School of Dentistry of the Federal University of Goias, Brazil. The research protocol will be previously submitted for ethical approval by the local Ethical Research Committee and will be registered prospectively at the ClinicalTrial.gov database before initiating patient recruitment.
Participants Eligible participants will be subjects with an edentulous maxilla, wearing a conventional complete denture. They will be selected from the list of patients who received conventional treatment at least six months previously. The possible conditions of the mandibular arch will include fully dentate subjects, partially edentate wearing fixed or removable prostheses, fixed or removable implant-supported dentures, or a shortened dental arch.
During the recruitment phase of the study, they will be informed about the treatment to be provided, details about the clinical trial, and the need for collaboration in the prescribed procedures and post-treatment follow-up visits over a minimum 1-year period. The selected participants will sign an informed consent form to participate in the study.
Inclusion and exclusion criteria We will select participants ≥ 60 years of age, with an edentulous maxillary arch, wearing a complete maxillary denture evaluated as sufficient for surgical planning. At the implant site level, they should present a healed edentulous maxilla (minimum of twelve weeks since the last extraction), minimal ridge dimensions of 5.4 mm (width) by 12 mm (height) in the anterior and premolar maxillary area, allowing the placement of one-piece implants with a 2.4 mm-diameter and minimum length of 10 mm. General health condition should be a physical status ASA1 or ASA2.
Study Design
- Study Type
- Interventional
- Allocation
- Na
- Intervention Model
- Single Group
- Primary Purpose
- Treatment
- Masking
- None
Masking Description
Not applied
Eligibility Criteria
- Ages
- 60 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •≥ 60 years of age
- •healed dentulous maxillary arch (minimum of twelve weeks since the last extraction)
- •wearing a complete maxillary denture evaluated as sufficient for surgical planning
- •minimal ridge dimensions of 5.4 mm (width) by 12 mm (height) in the anterior and premolar maxillary area
- •bone dimensions allowing the placement of one-piece implants with a 2.4 mm-diameter and minimum length of 10 mm.
- •general health condition should be a physical status ASA1 or ASA2.
Exclusion Criteria
- •inability to perform adequate oral hygiene
- •incapability to provide written informed consent and compliance to the protocol
- •any contraindication for oral surgery such as but not limited to,
- •uncontrolled diabetes
- •immunosuppression
- •radiation or chemotherapy
- •antiresorptive medication such as bisphosphonates
- •presence of dental, periodontal or peri-implant disease in the opposing arch
- •presence of a conventional complete denture in the opposing arch (mandible)
- •presence of an insufficient partial removable denture or implant-overdenture in the opposing arch, which cannot be rendered sufficient by a reline
- •heavy smoking habit with > 20 cig/d
- •reported severe bruxism or clenching habits
- •clinically present oro-facial pain
- •depression with a Geriatric Depression Scale above 12
- •xerostomia with a stimulated salivary flow rate inferior to 0.7 ml/min
- •ridge morphology type IV (Cawood and Howell, 1988)
- •defects requiring bone augmentation procedures, or unhealthy soft tissues.
Arms & Interventions
One-piece titanium-zirconium mini implants
Six one-piece titanium-zirconium mini implants (Straumann® Mini Implant System, Institut Straumann AG, Switzerland) in the edentulous maxilla, using a partially-guided insertion protocol.
Intervention: Implant placement surgery (Procedure)
Outcomes
Primary Outcomes
Implant Survival and Success
Time Frame: Through study completion, an average of 1 year
Implant Survival and Success rate will be defined as followed: I - Success (optimum health) II - Satisfactory survival III - Compromised survival IV - Failure (clinical absolute failure) Any of following Additionally, fractured implants will be considered as failures, except fracture of the implant apex during implant placement. Any dental implant showing excessive bone loss, such as radiolucency or infection, shall be treated in the manner best suited to the well-being of the subject, including treatment to save the dental implant.
Accuracy of implant placement
Time Frame: 6 weeks
Assessment of the accuracy of the methods will be based on the measure of the difference between the actual and the planned position of the mini implants, based on the measurement of (1) the global deviations at the coronal and apical regions of the mini implants, (2) the vertical deviation, and (3) the apical angle deviation. The global deviation is defined as the 3D distance between the coronal/apical centers of the planned and placed implants. The vertical deviation is the distance between the coronal center of the longitudinal axis of the planned implant and a plane parallel through the coronal center of the placed implant. The angle deviation will be measured as the angular divergence between the longitudinal axes of the planned and actual position of the mini implants. The divergence of the implant axis (in degrees) will also be recorded.
Oral health-related quality of life impacts
Time Frame: 1 year
Overall impacts of treatment on oral health-related quality of life will be assessed using the Oral Health Impact Profile instrument for edentulous subjects (OHIP-EDENT). It contains 19 questions in seven domains and proved to be sensitive to changes in prosthetic treatment and oral health. For each of the questions, subjects are asked how frequently they have experienced the event during the last month. Responses are given on a 5-item Likert scale. In this study, the validated Portuguese translation of the questionnaire will be utilized.
Denture Satisfaction Index
Time Frame: 1 year
Denture satisfaction will be evaluated by using the Denture Satisfaction Index (DSI; (25)), a 10mm visual analogue scale (VAS)-based questionnaire. This index evaluates ease of cleaning, general satisfaction, speech, comfort, aesthetics, stability, chewing ability, function and the general oral condition.
Prosthetic Success and Survival
Time Frame: Through study completion, an average of 1 year
One of the following: * Patrix fracture * Dislodged, worn or loose matrix housing * Matrix replacement * Matrix fracture * Fracture of the implant-supported overdenture * Fracture of the acrylic above a patrix * Fracture of denture teeth * Relining of implant overdenture A failure will be defined as an event leading to the loss of the reconstruction and need for the fabrication of a new overdenture.
Surgery intercurrencies and complications
Time Frame: 6 weeks
Any complications associated with the surgical procedures, or deviations from the prescribed protocol due to surgical intercurrences will be recorded. These include failed drilling of the planned implant site, need to raise a flap for adequate positioning of the needle drill, fracture of the bone walls, insufficient insertion torque (\< 10 Ncm), early implant failure, and others.
Treatment intercurrencies and complications
Time Frame: Through study completion, an average of 1 year
Any post-treatment complications associated with the use of the maxillary overdenture
Oral health-related quality of life impacts
Time Frame: 6 months
Overall impacts of treatment on oral health-related quality of life will be assessed using the Oral Health Impact Profile instrument for edentulous subjects (OHIP-EDENT). It contains 19 questions in seven domains and proved to be sensitive to changes in prosthetic treatment and oral health. For each of the questions, subjects are asked how frequently they have experienced the event during the last month. Responses are given on a 5-item Likert scale. In this study, the validated Portuguese translation of the questionnaire will be utilized.
Denture Satisfaction Index
Time Frame: 6 months
Denture satisfaction will be evaluated by using the Denture Satisfaction Index (DSI; (25)), a 10mm visual analogue scale (VAS)-based questionnaire. This index evaluates ease of cleaning, general satisfaction, speech, comfort, aesthetics, stability, chewing ability, function and the general oral condition.
Secondary Outcomes
- Pocket probing depth(1-year)
- Width of the keratinized tissue(1-year)
- Plaque index(1-year)
- Peri-implant bone loss(1-year)
- Chewing efficiency(1-year)
- Bleeding on probing(1-year)
- Implant Stability - Final insertion torque(During surgery)
- Implant Stability - Periotest value(1 year)
- Maximum voluntary bite force (MBF)(1-year)
- Implant Stability - Peak insertion torque(During surgery)
- Implant Stability - Final insertion torque(1-year)
- Implant Stability - Periotest value(During surgery)
Investigators
Cláudio Rodrigues Leles
Full Professor
Universidade Federal de Goias