Four Locator Attachment Mandibular Overdentures

Study Overview
=================
Brief Summary
-----------------
. There is little information on the degree of crestal bone loss around 4 inter-foraminal implant-retained mandibular overdentures (OVDs) and the amount of bone remodelling on the anterior maxilla and posterior mandibule on long-term function, particularly with different distributions.

Detailed Description
-----------------
Numerous studies confirm the successful use of implants to retain prostheses in the edentulous atrophic mandible. It has been recommended by some authors that clinicians should use 3 or 4 implants in situations that require increased retention, such as high muscle attachment or prominent mylohyoid ridge. LOCATOR attachment as a retentive component has several advantages over other systems, Such as: dual retention through both external and internal mating surfaces, a self-aligning feature which is helpful in guiding patients when placing their denture. There is little information on the degree of crestal bone loss around 4 inter-foraminal implant-retained mandibular overdentures (OVDs) and the amount of bone remodelling on the anterior maxilla and posterior mandibule on long-term function, particularly with different distributions.

Official Title
-----------------
Ten Years Retrospective Study of 4 LOCATOR Attachment of Mandibular Implant Retained Overdenture With 2 Different Distributions.

Conditions
-----------------
Bone Resorption

Intervention / Treatment
-----------------
* Other: observation


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Patients with 4 implants in the inter-foraminal region. Patients treated by staff and students in the Master's program in Prosthodontics Department according to the following criteria: Edentulous maxilla and mandible for at least 1 year. Problems with retention and stability of the mandibular denture. Mandibular bone height between 15 and 25 mm. Exclusion Criteria: Patients with relative contraindications, such as A history of para functional habits. Smokers more than 10 cigarettes per day. alcoholism. Patients with a history of radiation therapy in the head and neck region . • Patients within intravenous administrated bisphosphonates., chemotherapy, and mental disorders that could jeopardies their co-operation.

Ages Eligible for Study
-----------------
Minimum Age: 55 Years
Maximum Age: 80 Years

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

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

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Quadrilateral distribution group<br>Patients with quadrilateral distribution of implants | Other: observation<br>* To compare the effect of the mandibular implant retained OVD using quadrilateral distribution (QD) versus linear distribution (LD) on posterior mandibular ridge resorption (PMandRR), anterior maxillary ridge resorption (AMaxRR), and changes to the crestal bone level around implants after 10 years of function.<br>|
| Linear distribution group<br>Patients with lineardistribution of implants | Other: observation<br>* To compare the effect of the mandibular implant retained OVD using quadrilateral distribution (QD) versus linear distribution (LD) on posterior mandibular ridge resorption (PMandRR), anterior maxillary ridge resorption (AMaxRR), and changes to the crestal bone level around implants after 10 years of function.<br>|

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

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Posterior mandibular ridge resorption (PMandRR) | The amount of PMandRR will be assessed using posterior area index on a panoramic x-ray which use specific landmarkds. | 10 years retrospective study | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Anterior maxillary ridge resorption (AMaxRR) | The amount of PMandRR will be assessed using anterior area index on a panoramic x-ray, which use specific landmarks. | 10 years |