Mandibular Overdentures Retained by Mini Implants: a Clinical Trial Comparing Different Surgical and Loading Protocols

NCT04760457 | Completed

• 1 other identifier: PI04011-2019
• Study Type: interventional
• Target: 74
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to test the combined effects of different loading protocols and surgical approaches on clinical and patient-reported outcome measures (PROMs) following the use of four mini implants for mandibular overdenture retention. The main study hypotheses are:

1. 1.There are significant improvements in PROMs following implant intervention compared to baseline measures;
2. 2.Immediately loaded mini implants have similar failure rates compared to mini implants receiving a delayed 6-week protocol.
3. 3.Flapless surgery has similar post-insertion outcomes compared to flapped surgery.

Conditions

Edentulous Mouth; Complete Edentulism

Keywords

Overdenture; Mini implant; Flapless surgery; Dental implant; Implant loading protocol

Outcome Measures

Primary Outcomes (16)

• Patient-perceived burdens

  The Burdens in Oral Surgery Questionnaire (BiOS-Q) will be used to assess patient-perceived burdens. It includes 16 items concerning all aspects of procedures occurring during a surgery. Responses for each item are assessed using a visual analogue scale (VAS) ranging from 0 = no expression of the attribute (e.g. not unpleasant at all) to 100 = maximum expression (e.g. very unpleasant).

  Twenty-four hours after implant surgery.

• Implant survival and success

  Each implant will be assessed according to the health scale of the International Congress of Oral Implantologists (ICOI-Pisa health scale). After clinical assessment, each implant will be classified as 'success', 'satisfactory survival', 'compromised survival' or 'failure'.

  Incidence thoughout the 12-month follow-up after implant placement.

• Postoperative pain and discomfort

  A 100-cm graduated visual analog scale will be used to evaluate participants' assessments of pain and discomfort regarding the surgical process. Each participant will indicate their level of pain and discomfort with each parameter by marking a point along the scale.

  Assessed 24 hours after implant placement.

• Postoperative pain and discomfort

  A 100-cm graduated visual analog scale will be used to evaluate participants' assessments of pain and discomfort regarding the surgical process. Each participant will indicate their level of pain and discomfort with each parameter by marking a point along the scale.

  Assessed 72 hours after implant placement.

• Postoperative pain and discomfort

  A 100-cm graduated visual analog scale will be used to evaluate participants' assessments of pain and discomfort regarding the surgical process. Each participant will indicate their level of pain and discomfort with each parameter by marking a point along the scale.

  Assessed 1 week after implant placement.

• Consumption of analgesics

  The number of analgesics consumed by the participant during the post-operative and healing period will be recorded in the patient's file.

  Assessed until 1 week after implant placement.

• Patient Satisfaction

  The McGill Denture Satisfaction Instrument - DSI (Awad \& Feine, 1998; de Grandmont et al., 1994) will be used to assess patients' satisfaction relating to their prostheses. This is a treatment-specific patient-based outcome assessing satisfaction relating to several aspects of the mandibular prosthesis, including general satisfaction, comfort, stability, aesthetics, chewing ability (ease of chewing), chewing efficiency (ability to crush food in small particles), ease of cleaning, ability to speak and oral condition (condition of their mouth, which can refer to oral health status and was measured by "In general, are you satisfied with your oral condition?''. The subjects will answer on a 100 mm visual analogue scale (VAS) anchored by the words 'not at all satisfied' and 'extremely satisfied'.

  Assessed at baseline (before implant surgery)

• Patient Satisfaction

  The McGill Denture Satisfaction Instrument - DSI (Awad \& Feine, 1998; de Grandmont et al., 1994) will be used to assess patients' satisfaction relating to their prostheses. This is a treatment-specific patient-based outcome assessing satisfaction relating to several aspects of the mandibular prosthesis, including general satisfaction, comfort, stability, aesthetics, chewing ability (ease of chewing), chewing efficiency (ability to crush food in small particles), ease of cleaning, ability to speak and oral condition (condition of their mouth, which can refer to oral health status and was measured by "In general, are you satisfied with your oral condition?''. The subjects will answer on a 100 mm visual analogue scale (VAS) anchored by the words 'not at all satisfied' and 'extremely satisfied'.

  Assessed at the 3-month follow-up visit after implant placement.

• Patient Satisfaction

  The McGill Denture Satisfaction Instrument - DSI (Awad \& Feine, 1998; de Grandmont et al., 1994) will be used to assess patients' satisfaction relating to their prostheses. This is a treatment-specific patient-based outcome assessing satisfaction relating to several aspects of the mandibular prosthesis, including general satisfaction, comfort, stability, aesthetics, chewing ability (ease of chewing), chewing efficiency (ability to crush food in small particles), ease of cleaning, ability to speak and oral condition (condition of their mouth, which can refer to oral health status and was measured by "In general, are you satisfied with your oral condition?''. The subjects will answer on a 100 mm visual analogue scale (VAS) anchored by the words 'not at all satisfied' and 'extremely satisfied'.

  Assessed at the 6-month follow-up visit after implant placement.

• Patient Satisfaction

  The McGill Denture Satisfaction Instrument - DSI (Awad \& Feine, 1998; de Grandmont et al., 1994) will be used to assess patients' satisfaction relating to their prostheses. This is a treatment-specific patient-based outcome assessing satisfaction relating to several aspects of the mandibular prosthesis, including general satisfaction, comfort, stability, aesthetics, chewing ability (ease of chewing), chewing efficiency (ability to crush food in small particles), ease of cleaning, ability to speak and oral condition (condition of their mouth, which can refer to oral health status and was measured by "In general, are you satisfied with your oral condition?''. The subjects will answer on a 100 mm visual analogue scale (VAS) anchored by the words 'not at all satisfied' and 'extremely satisfied'.

  Assessed at the 12-month follow-up visit after implant placement.

• Oral health-related quality of life (OHRQoL)

  The cross-culturally adapted Brazilian version of the Oral Health Impact Profile for edentulous subjects (OHIP-EDENT) will be used. It contains 19 items divided in four different subscale domains: (I) masticatory discomfort and disability (four items), (II) psychological discomfort and disability (five items), (III) social disability (five items), and (IV) oral pain and discomfort (five items). The items are answerable by a 3-point Likert scale and responses will be summed to result an overall score. Higher scores represent worse OHRQoL.

  Assessed at baseline (before implant surgery).

• Oral health-related quality of life (OHRQoL)

  The cross-culturally adapted Brazilian version of the Oral Health Impact Profile for edentulous subjects (OHIP-EDENT) will be used. It contains 19 items divided in four different subscale domains: (I) masticatory discomfort and disability (four items), (II) psychological discomfort and disability (five items), (III) social disability (five items), and (IV) oral pain and discomfort (five items). The items are answerable by a 3-point Likert scale and responses will be summed to result an overall score. Higher scores represent worse OHRQoL.

  Assessed at the 3-month follow-up visit after implant placement.

• Oral health-related quality of life (OHRQoL)

  The cross-culturally adapted Brazilian version of the Oral Health Impact Profile for edentulous subjects (OHIP-EDENT) will be used. It contains 19 items divided in four different subscale domains: (I) masticatory discomfort and disability (four items), (II) psychological discomfort and disability (five items), (III) social disability (five items), and (IV) oral pain and discomfort (five items). The items are answerable by a 3-point Likert scale and responses will be summed to result an overall score. Higher scores represent worse OHRQoL.

  Assessed at the 6-month follow-up visit after implant placement.

• Oral health-related quality of life (OHRQoL)

  The cross-culturally adapted Brazilian version of the Oral Health Impact Profile for edentulous subjects (OHIP-EDENT) will be used. It contains 19 items divided in four different subscale domains: (I) masticatory discomfort and disability (four items), (II) psychological discomfort and disability (five items), (III) social disability (five items), and (IV) oral pain and discomfort (five items). The items are answerable by a 3-point Likert scale and responses will be summed to result an overall score. Higher scores represent worse OHRQoL.

  Assessed at the 12-month follow-up visit after implant placement.

• Prosthodontic maintenance events

  The incidence of prosthodontic repair/adjustment events will be recorded during the clinical assessments.

  Throughout 12 months after overdenture delivery.

• Surgical time

  The time interval concerning the clinical visit for implant placement and delivery of the overdenture or denture adaptation will me measured and registered.

  Procedure (Assessed during the clinical visit of implant placement and overdenture delivery or denture adaptation.)

Secondary Outcomes (17)

• Masticatory Performance

  Assessed at baseline (before implant surgery).

• Masticatory Performance

  Assessed at the 3-month follow-up visit after implant placement.

• Masticatory Performance

  Assessed at the 6-month follow-up visit after implant placement.

• Masticatory Performance

  Assessed at the 12-month follow-up visit after implant placement.

• Maximum voluntary bite force

  Assessed at baseline (before implant surgery).

Study Arms (4)

IL-FLS

ACTIVE COMPARATOR

Immediate loading (IL) and Flapless surgery (FLS)

Procedure: Implant placement with flapless surgery; Procedure: Implant immediate loading

IL-FPS

ACTIVE COMPARATOR

Immediate loading (IL) and Flapped surgery (FPS)

Procedure: Implant placement with flapped surgery; Procedure: Implant immediate loading

DL-FLS

ACTIVE COMPARATOR

Delayed loading (DL) and Flapless surgery (FLS)

Procedure: Implant placement with flapless surgery; Procedure: Implant delayed loading

DL-FPS

ACTIVE COMPARATOR

Delayed loading (DL) and Flapped surgery (FPS)

Procedure: Implant placement with flapped surgery; Procedure: Implant delayed loading

Interventions

Implant placement with flapped surgery PROCEDURE

Four mini implants will be placed reflecting a flap.

DL-FPS; IL-FPS

Implant placement with flapless surgery PROCEDURE

Four mini implants will be placed without reflecting a flap.

DL-FLS; IL-FLS

Implant immediate loading PROCEDURE

Four mini implants will be immediately loaded.

IL-FLS; IL-FPS

Implant delayed loading PROCEDURE

Four mini implants will be loaded after a 6-week healing period.

DL-FLS; DL-FPS

Eligibility Criteria

• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• No contraindications for implant surgery (mainly related to uncontrolled systemic diseases);
• Enough bone height in the interforaminal area for an implant length of at least 10 mm;
• Ability to understand and answer the questionnaires used in the study and agree to participate by providing a written informed consent.

You may not qualify if:

• Noncompliant participants;
• Disagreement to be randomly allocated to the treatment study groups;
• Signs of untreated temporomandibular disorders or uncontrolled systemic or oral conditions that require additional treatments.

Sponsors & Collaborators

• Universidade Federal de Goias: lead
• ITI International Team for Implantology, Switzerland: collaborator
• Institut Straumann AG: collaborator

Study Sites (1)

School of Dentistry, Federal University of Goias

Goiânia, Goiás, 74605-220, Brazil

Location

Related Publications (19)

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• Misch CE, Perel ML, Wang HL, Sammartino G, Galindo-Moreno P, Trisi P, Steigmann M, Rebaudi A, Palti A, Pikos MA, Schwartz-Arad D, Choukroun J, Gutierrez-Perez JL, Marenzi G, Valavanis DK. Implant success, survival, and failure: the International Congress of Oral Implantologists (ICOI) Pisa Consensus Conference. Implant Dent. 2008 Mar;17(1):5-15. doi: 10.1097/ID.0b013e3181676059.

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• Ferreira de Sa J, Nascimento LN, de Moraes Sousa JF, Curado TFF, Srinivasan M, McKenna G, Schimmel M, Leles CR. The Effect of Implant Distribution on Functional and Patient-Reported Outcomes of Mandibular Overdentures Retained by Four Mini Implants. J Oral Rehabil. 2025 Sep;52(9):1452-1460. doi: 10.1111/joor.14024. Epub 2025 May 9.

  PMID: 40346748 DERIVED

• Curado TFF, Nascimento LN, Silva JR, de Paula MS, Schimmel M, McKenna G, Leles CR. Mandibular overdenture retained by four one-piece titanium-zirconium mini implants: A 2-year RCT on patient-reported outcomes. J Dent. 2024 Oct;149:105267. doi: 10.1016/j.jdent.2024.105267. Epub 2024 Jul 26.

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• Leles CR, Curado TFF, Nascimento LN, Silva JR, de Paula MS, McKenna G, Schimmel M. Changes in masticatory performance and bite force after treatment with mandibular overdentures retained by four titanium-zirconium mini implants: One-year randomised clinical trial. J Oral Rehabil. 2024 Aug;51(8):1459-1467. doi: 10.1111/joor.13722. Epub 2024 Apr 29.

  PMID: 38685704 DERIVED

MeSH Terms

Conditions

Mouth, Edentulous

Interventions

Immediate Dental Implant Loading

Condition Hierarchy (Ancestors)

Mouth Diseases; Stomatognathic Diseases; Tooth Diseases

Intervention Hierarchy (Ancestors)

Dental Implantation, Endosseous; Dental Implantation; Oral Surgical Procedures, Preprosthetic; Oral Surgical Procedures; Surgical Procedures, Operative; Prosthesis Implantation; Dentistry; Prosthodontics

Study Officials

• Claudio R Leles, DDS, PhD

  Universidade Federal de Goias

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: The assessment of longitudinal outcomes will be performed by an assessor blinded to the surgical/loading protocols
• Purpose: TREATMENT
• Intervention Model: FACTORIAL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Full Professor

Model Details: A factorial experiment of two factors is planned, each with two possible values or "levels", and whose experimental units take on all possible combinations of these levels across all such factors (2×2 factorial design), allowing the study to determine the effect of each factor on the response variable, as well as the effects of interactions between factors on the response variable. The tested factors will be: loading protocol (immediate or delayed), and surgical approach (flapped or flapless), resulting in a factorial experiment with four treatment combinations in total. Hence, the design is denoted a 2² factorial, which identifies the number of factors (n=2) and how many levels each factor has (n=2) there are in the design (2²=4).

Study Record Dates

• First Submitted: January 27, 2021
• First Posted: February 18, 2021
• Study Start: March 1, 2021
• Primary Completion: November 30, 2022
• Study Completion: November 30, 2022
• Last Updated: May 10, 2023

Record last verified: 2023-05

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL
• Time Frame: Data will be available after publication of the results in high-impact journals, and until two years hereafter
• Access Criteria: Upon request to the study coordinator

Locations

BR (1)