Clinical, Radiological and Microbiological Outcomes of Implants With Two Different Connection Configurations, a Split-mouth RCT.

Study Overview
=================
Brief Summary
-----------------
This study designed as a randomized controlled split-mouth trial will be conducted at the Dental Clinic of the University of Valencia. The aim will be to assess differences in clinical, radiological and microbiological outcomes between implants with 2 different connections: internal hexagon and conical connection. Following the premises, to minimize the bias related to prosthetic phase and maximize the effect of connections on MBL changes, a 1abutment-1time protocol will be used. The study hypothesis is that there will be no statistically significant differences between both implant connections.

Official Title
-----------------
Clinical, Radiological and Microbiological Outcomes of Implants With Two Different Connection Configurations, a Split-mouth RCT.

Conditions
-----------------
Bone Loss, Alveolar, Dental Implant Failed

Intervention / Treatment
-----------------
* Device: Rehabilitation with dental implant with internal hexagon connection
* Device: Rehabilitation with dental implant with conical connection


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: able to sign an informed consent form aged 25 years or more Any patient requiring two implant-supported crowns in the lower or upper jaw Kennedy class I, II, and III; teeth extracted at least 6 months before implant placement; sufficient bone volumes to accommodate dental implants without augmentation procedure Exclusion Criteria: General medical and/or psychiatric contraindications to implant surgery, Pregnancy or nursing, Heavy smoking (more than 10 cigarettes/day), Treatment with anticoagulant drugs (International Normalized Ratio under 1.8), bisphosphonates, steroid therapy or anticonvulsants drugs. No regenerated bone Untreated Periodontal disease and inability of the patient to maintain reasonable oral hygiene according to study requirements. Patients with history of alcohol, narcotics or drug abuse. (Alcoholism: more than two bottles of beer per day) Patients receiving radiotherapy, chemotherapy or any other immunosuppressive treatment, or who have been administered radiotherapy in the last 5 years. (Patients through at any time received radiotherapy to the head and neck region should be excluded anyway.) Metabolic bone disorders Uncontrolled bleeding disorders such as: hemophilia, thrombocytopenia, granulocytopenia. Degenerative diseases. Osteoradionecrosis. Renal failure. Organ transplant recipients. HIV positive. Malignant diseases. Diseases that compromise the immune system. Unbalanced diabetes mellitus. (HbA1c above 6.5), Uncontrolled endocrine diseases Psychotic diseases. Hypersensitivity to one of the components of the implant in general and titanium in particular. Women who are pregnant or lactating. Lack of patient cooperation. Parafunctional habits, such as Bruxism or Temporomandibular joint disease. Various pathologies of the oral mucosa for example: Benign mucous pemphigoid, desquamative ginigivitis, erosive lichen planus, malignancy of oral cavity, bolus erosive diseases of the oral mucosa.

Ages Eligible for Study
-----------------
Minimum Age: 25 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Internal hexagon connection<br>Small flaps will be elevated to reduce any kind of injury on the periosteum and maintain the blood supply during the healing period. Patients will receive 2 implants. One implant (assigned randomly) will have internal hexagon connection. The Internal Hex (IH) implant has a 2.5mm internal hexagon and a 90° cone. The platform diameter is Ø3.5mm. | Device: Rehabilitation with dental implant with internal hexagon connection<br>* All patients will receive an implant with internal hexagon connection. All implants will be10 mm in length and 3.75 mm in diameter. Implants will be inserted slightly subcrestal. Bone levels will be measured using a calibrated probe. Torque insertion will be assed using W&H machine Once inserted, implants will be connected to smart pegs to test primary stability. A periapical x-ray will be done after the operation. Thereafter, a specific coping for digital impression will be connected to the implant and a digital impression will be taken. Aim of this procedure will be to produce a screw retained definitive zirconia prosthesis to be adapted at the time of second surgery<br>|
| Experimental: Conical connection<br>Small flaps will be elevated to reduce any kind of injury on the periosteum and maintain the blood supply during the healing period. Patients will receive 2 implants. One implant (assigned randomly) will have internal hexagon connection. The Conical Standard (CS) implant has a 2.5mm internal hexagon and 22° cone. The platform diameter is Ø3.1mm. | Device: Rehabilitation with dental implant with conical connection<br>* All patients will receive an implant with conical connection. All implants will be10 mm in length and 3.75 mm in diameter. Implants will be inserted slightly subcrestal. Bone levels will be measured using a calibrated probe. Torque insertion will be assed using W&H machine Once inserted, implants will be connected to smart pegs to test primary stability. A periapical x-ray will be done after the operation. Thereafter, a specific coping for digital impression will be connected to the implant and a digital impression will be taken. Aim of this procedure will be to produce a screw retained definitive zirconia prosthesis to be adapted at the time of second surgery<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Peri-implant bone level changes | calculated using intraoral digital periapical radiographs | a. implant placement (baseline), b. abutment connection (8-12 weeks), c. after 1 year of function (14-15 months), d. after 3 years of function (38-39 months). | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Implant failure | Requiring removal | 3 years | 
| Prosthetic complications | Screw loosening or fracture, fracture of the prosthesis or of the ceramic | 3 years | 
| Resonance frequency analysis values | Measured using Ostell Mentor | a. implant placement (baseline) b. abutment connection (8-12 weeks) | 
| Probing pocket depth | Measurement of peri-implant pocket depth with a periodontal probe | a. implant placement (baseline), b. abutment connection (8-12 weeks), c. after 1 year of function (14-15 months), d. after 3 years of function (38-39 months). | 
| Microbial loads | Quantities of different microbial species assessed using 16s metagenomics | 12 months after loading | 
| Plaque | Presence or absence of plaque | a. implant placement (baseline), b. abutment connection (8-12 weeks), c. after 1 year of function (14-15 months), d. after 3 years of function (38-39 months). | 
| Bleeding on probing | Presence or absence of bleeding after probing pocket depth | a. implant placement (baseline), b. abutment connection (8-12 weeks), c. after 1 year of function (14-15 months), d. after 3 years of function (38-39 months). |