A Cost-effectiveness Analysis of the Single-implant Mandibular Overdenture Treatment (SIMOECON)

Universidade Federal de Goias

Status: Completed

Conditions: Mouth, Edentulous

Treatments: Procedure: Mandibular Overdenture; Procedure: Mandibular complete denture

Study type: Interventional

Funder types: Other

Identifiers

NCT02710357

966_2014

Details and patient eligibility

About

The aim of this study is to assess the cost-effectiveness of the mandibular overdenture retained by a single implant. The study hypothesis is that SIMO is more effective but more costly than the conventional denture, though this incremental cost is relatively low for the offered effectiveness in terms of clinical and patient-reported outcomes.

Full description

This randomized clinical trial alongside a cost-effectiveness analysis will include twenty-eight edentulous individuals who meet eligibility criteria. New maxillary and mandibular dentures will be fabricated for all participants following a standardized protocol. Then, participants will be randomized into one of the treatment groups: conventional complete denture group or single-implant mandibular overdenture group. Each participant allocated to the overdenture group will then receive a Straumann® Standard Plus SLActive® regular neck implant (Straumann 0.33.051S/052S/053S Institute Straumann AG, Basel, Switzerland) in the mandibular midline. A healing abutment will be connected and the implant will be allowed to heal for approximately 3 weeks. Then, a 3.4mm retentive titanium anchor abutment (Straumann 048.439, Institute Straumann AG, Basel, Switzerland) will be connected and tightened to 35 N.cm with a torque wrench. The matrix will be incorporated to the denture using self-curing acrylic resin and the patient will be instructed to keep the upper and lower dentures firmly occluded in the habitual position until the final polymerization of the resin. Direct costs related to therapies in both groups will be identified, measured and valuated for one year after treatment and patient-reported outcomes will be assessed. Incremental cost-effectiveness ratios will be estimated and graphically presented on cost-effectiveness planes. A Markov decision tree will be constructed to set out the consequences of the competing alternatives. Sensitivity analysis on the most important assumptions will be performed in order to assess the robustness of the model.

Enrollment: 28 estimated patients

Sex: All

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• No contraindications for implant surgery (mainly related to uncontrolled systemic diseases)
• Present enough bone volume in the mandibular midline area for implant placement without the need of bone augmentation procedures.
• Be able to understand and answer the questionnaires used in the study
• Agree to participate by providing a written informed consent.

Exclusion criteria

• Noncompliant participants
• Individuals who do not agree to be randomly allocated to the treatment study group
• Presence of signs of untreated temporomandibular disorders, uncontrolled systemic or oral conditions that require additional treatments

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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28 participants in 2 patient groups

Mandibular complete denture

Active Comparator group

Description:

Participants allocated to this group will not receive any additional treatment. When needed, retreatment or any adjustment/repair in the dentures will be performed accordingly. Participants will receive regular maintenance for their dentures, including adjustments for the elimination of sore areas, denture relining and repair of fractures, when needed, until the end of the follow-up period.

Treatment:

Procedure: Mandibular complete denture

Single-implant mandibular overdenture

Experimental group

Description:

Participants allocated to this group will have an implant placed in the mandibular midline and after 4 weeks (healing period - early loading) an attachment system will be tightened and a retention matrix will be incorporated to the mandibular denture.

Treatment:

Procedure: Mandibular Overdenture