The Effects of Dis/Reconnection of Implant Abutments on Peri-implant Bone Levels

Study Overview
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Brief Summary
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The aim of this prospective study is to assess the effects of definitive abutment connection at the time of implant placement on bone level changes in the areas of the posterior maxilla and mandible.

Detailed Description
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A total of 38 implants will be placed in 19 patients with at least 2 missing posterior teeth in the maxilla and the mandible for this study. Definitive prefabricated abutments will be connected at implant placement. The abutment (control group) on one of the two implants will be randomly selected to go through one complete cycle of complete disconnection and reconnection by hand at 16- (DR1), 19- (DR2), 22- (DR3), and 24- (DR4) weeks after implant surgery. The abutment (test group) on the other implant will be left undisturbed throughout the duration of the study. All implants will remain unrestored within the study period (12 months). Peri-implant bone level changes will be assessed using standardized periapical radiographs immediately after implant placement (T0), at 3-(T3), 6-(T6) and 12-(T12) month follow-up examinations and during each disconnection of the abutments.

Official Title
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The Effects of Disconnection and Reconnection of Implant Abutments on Peri-implant Bone Levels: a 1-year Prospective Study

Conditions
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Bone Loss, Gum Recession

Intervention / Treatment
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* Device: Definitive abutment


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Minimum age 18 Good oral hygiene Healed site that possess two or more missing teeth in the maxillary or mandibular posterior region (excluding third molars) Adequate bone to accommodate at least a 4.3 mm diameter and 8mm length implant at each site Have at least 8mm interocclusal restorative space Willing to participate and attend the planned follow-up visits. Exclusion Criteria: History of alcohol/drug dependency, or any medical, physical, or psychological factor that might affect the surgical or prosthodontic procedures and follow-up examinations History of radiation therapy to the head and neck region History or current habit of smoking History or current habit of bruxism No opposing occluding dentition or prostheses Need for bone augmentation during implant placement Implant insertion torque value <35 Ncm

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Single center, prospective, randomized modified split mouth clinical trial
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control group<br>Healing abutments are connected on the implants on the day of surgery, which will be subjected to multiple disconnection and reconnection during the prosthetic phase | |
| Experimental: Test group<br>Definitive abutments connected to the implants on the day of surgery. No disconnection or reconnection during the prosthetic phase | Device: Definitive abutment<br>* With two height options available, On1 Base are selected depending on the thickness of the soft tissue. It remains in position from implant placement to finalization, which leaves the soft tissue undisturbed for optimized healing, moved the restorative platform of Nobel Biocare conical connection implants from bone level to tissue level, thereby simplifying the restorative procedures<br>* Other names: On1 Concept;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in bone level between baseline surgery and 12 months | Bone level will be measured by periapical radiograph to assess for bone loss after dental implant | At baseline (prior to surgical implantation), and 12 months after surgical implantation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Level of radiolucency after implant | A successful implant will be determined by the degree of radiolucency around the implant 12 months after surgery. Radiolucency will be measured by periapical radiograph at baseline prior to surgery and at 12 months after dental implant surgery. Normal degrees of radiolucency are within 2mm at the crestal region and no radiolucency around the body of the implant | At baseline (prior to surgical implantation), and 12 months after surgical implantation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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One abutment one time, Disconnection reconnection, Definitive abutment