Maintenance and Tissues Conditions of Fixed Screw-Retained Implant Prosthesis Versus Implant-Retained Ball Overdentures


The aim of this study was to compare the prosthetic maintenance requirements between implant-retained ball overdentures versus fixed screw- retained implant prosthesis. Clinical and radiographic changes in peri-implant tissue with using PGE2 as a PICF biomarker were also evaluated. Selected patients had been divided into two groups: 1. Group (I): twenty seven patients had received implant-Supported ball over dentures. 2. Group (II): twenty-seven patients had received screw retained restorations Interventions and study procedures Surgical and prosthetic procedures: Surgical Procedures A radiopaque radiographic stent was formed and was positioned in the patient's mouth during cone beam scanning. Four implants were planned with two virtual replicas, in the place of the lateral incisor and the second premolar. The stent was fabricated. After the healing period of four months finished, the patients were recalled and the super structure was fabricated according to the type of restoration Follow-up During the 12 months follow-up period, prosthodontic complications were recorded and calculated. Postoperative care Along with a conventional oral hygiene assessment and functional checkup, follow up visits were scheduled every 6 months and up to 12 months total follow up period. Clinical soft tissue measurements which include plaque index (PI), gingival index (GI), and PPD were measured at the mid-facial, mid-lingual, mid-mesial, and mid-distal aspects of each fixture using a graduated plastic probe to the nearest 0.5 mm. These clinical measurements were recorded after prosthesis delivery, 6 and 12 months postoperatively. The peri-implant marginal bone loss (MBL) was assessed radiographically after prosthesis delivery, 6 and 12 months postoperatively. • Collection of peri-implant crevicular fluid (PICF) samples: PICF was collected.

Full Title of Study: “Prosthetic Maintenance and Peri- Implant Tissues Conditions of Fixed Screw- Retained Implant Prosthesis Versus Implant-Retained Ball Overdentures: A Randomized Clinical Trial”

Study Type

  • Study Type: Interventional
  • Study Design
    • Allocation: Randomized
    • Intervention Model: Parallel Assignment
    • Primary Purpose: Treatment
    • Masking: Single (Outcomes Assessor)
  • Study Primary Completion Date: November 1, 2020


  • Procedure: Screw retained restoration
    • Hybrid prosthesis
  • Procedure: implant-retained ball overdentures
    • Removable prosthesis

Arms, Groups and Cohorts

  • Active Comparator: screw retained restorations
  • Other: implant-retained ball overdentures

Clinical Trial Outcome Measures

Primary Measures

  • Rate of prosthetic complications
    • Time Frame: 12 months

Secondary Measures

  • changes in peri-implant tissue with using PGE2 as a PICF biomarker
    • Time Frame: 12 months

Participating in This Clinical Trial

Inclusion Criteria

  • Completely edentulous patients have Angle Class I maxilla-mandibular relationship. – Age range between 40 and 70. – Maxillary and mandibular ridges with no history of fresh extraction. – Sufficient bone volume to house four implants in each arch. – Sufficient zone of keratinized attached mucosa >5mm over the crest of the upper and lower ridges. Exclusion Criteria:

  • the patients have a past history of head and neck radiation – previous ridge augmentation or grafting – Lack of any systemic diseases that could affect osseointegration of implants as uncontrolled diabetes , hypertension , and osteoporosis – Heavy smokers who exceeding 20 cigarette/ day – para-functional habits for example bruxism or clenching.

Gender Eligibility: All

Minimum Age: 40 Years

Maximum Age: 70 Years

Are Healthy Volunteers Accepted: Accepts Healthy Volunteers

Investigator Details

  • Lead Sponsor
    • Kafrelsheikh University
  • Provider of Information About this Clinical Study
    • Principal Investigator: Nourhan Ahmed Ragheb, principal invistigator – Kafrelsheikh University
  • Overall Official(s)
    • Nourhan Ragheb, PhD, Principal Investigator, Kafrelsheikh University

Clinical trials entries are delivered from the US National Institutes of Health and are not reviewed separately by this site. Please see the identifier information above for retrieving further details from the government database.

At, we keep tabs on over 200,000 clinical trials in the US and abroad, using medical data supplied directly by the US National Institutes of Health. Please see the About and Contact page for details.