Evaluation of the Abutment Type Following Oral Implants in Terms of the Surrounding Bone Height

Evaluation of Two Different Types of Abutments on Post-prosthesis Bone Resorption: A Randomized Controlled Clinical and Radiological Trial

Compare two different types of abutments (molded abutments and computer-designed 3D printed abutments) in terms of the amount of bone loss, and depth of periodontal pockets around the implant during different periods.

In the past few years, the number of research conducted on the designs of abutments and materials has increased. Often, the restoration is done over the implant using standard abutments that the implant company prefabricated, but due to the problems facing the dentist from the occurrence of bone absorption, an increase in the depth of the pocket after restoration, other types of abutment design methods have been introduced as needed (molded abutment made by lost wax technique and computer-designed abutment made using a 3D laser printer), those customised abutments were made special for each patient depending on their conditions.

A plastic abutment that is provided by the implant manufacturer will be used. This abutment will be modified using wax, and then it will be dismantled, wedged, and poured using a Ni-Cr mixture. A plastic abutment that the implant manufacturer provides will be used. This abutment will be modified using wax, and then it will be dismantled, wedged, and poured using a Ni-Cr mixture.

The customised abutment will be made using a laser printer with a Cr-Co mixture after being designed using a special computer program.

The waxed plastic abutment will dismantle, wedged, and poured using a Ni-Cr mixture then it will be trimmed to make it ready to make the permanent restoration over it. The prostheses will be cemented above the abutment using dual-cure resin cement then the final restoration (crown and abutment) will be fixed using a screw-retained manner.

A marker or Scan body appropriate for the type of implant will be placed on the laboratory implant substitute, a digital scan of the marker will be done in the lab, and the scanned image will be transferred to a computer design software where the prosthesis is designed, In the printing phase, the final prosthesis will be manufactured using a stepwise metal powder supply and a laser fusion process. Making the abutment ready to make the permanent restoration over it. The prostheses will be cemented above the abutment using dual-cure resin cement then the final restoration (crown and abutment) will be fixed using a screw-retained manner.

It Is the loss of bone that occurred around the dental implant neck after fixing the final prosthesis (abutment and crown). A periapical radiograph is going to be taken using a digital intra-oral sensor with a special holder in a parallel way, to measure the changes that occurred at the level of the bone around the implant depending on MBLS concept taking two referring points from the neck of the abutment to the first match of the bone with the abutment using special programs on computer (Photoshop) during different periods.

Periodontal pockets are spaces surrounding the implant under the gum line. The pocket around the implant will be measured by using special plastic probe slides between the implant and gum to measure the depth of the periodontal pocket, and the changes in the depth of pockets will be noted and register after fixing the final prosthesis (abutment and crown), during different periods.

T1: direct after cementation, T2:3 months after cementation, T3: 6 months after cementation, T4: 1 year after cementation

Inclusion Criteria: The patient's age is greater than 20 years and younger than 50 Good oral health Absence of systemic diseases that may affect the healing of surrounding tissues, such as diabetes. Exclusion Criteria: The presence of non-functional habits such as stridor Acute or acute periodontitis, previous loss of implants Poor general health conditions Previous radiotherapy in the head and neck area Mental incompetence Orthodontic treatment

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