Effect of Different Bar Designs on Axial and Nonaxial Retention Forces of Implant-Retained Maxillary Overdentures: An In Vitro Study

Effect of bar designs on peri implant tissues health in implant-supported removable prostheses: a systematic review

Different characteristics of bars (cross-sectional shape, diameter, distal extension etc.) lead to different biomechanical behavior (retention and stress) with implants and peri-implant tissues.Aim: To evaluate the impact of implant-supported removable prostheses bar designs in fully edentulous arch (in the maxilla and/or mandibula), with 4 implants or more, on the peri-implant soft and hard tissues.Two reviewers searched for observational studies, RCT and in vitro studies, published on five main databases and three from the grey literature, without restrictions on November 2023.Of the 3049 selected articles, four met the inclusion criteria. Four RCT evaluated peri-implant health tissues in full edentulous arches with 4 or 6 implants rehabilitated with implant bar overdentures. One prospective study with 5 years follow-up evaluated the success/survival rate of implants and implant bar overdentures. Overall, 261 subjects were enrolled in our systematic review with 1176 implants. Overdentures' survival rate was 100%. There was a trend that plaque indices and gingival indices were low in all of the studies, however no statistical analysis was done due to the lack of information.Due to the lack of information in the included studies, we cannot confirm if bar characteristics affect the peri-implant tissues health.

A technique for measuring the clinical retentive forces of mandibular implant-supported overdentures

A novel device for measuring the clinical retentive forces of mandibular implant overdentures is described. The device addresses several drawbacks of the conventionally used methods regarding the application of pure vertical dislodging forces perpendicular to the occlusal plane and the elimination of nonaxial dislodging forces and tipping or rotation of overdentures during the measurements. Moreover, the technique allows for the standardization of the occlusal plane and points of load application.

Rehabilitation of an Extremely Edentulous Atrophic Maxilla with a Pseudoskeletal Class III Relationship

The skeletal class III relationship presents complex dentoalveolar problems, requiring multidisciplinary treatment. In edentulous people, severe atrophy of the jawbone simulates the clinical appearance of a skeletal class III relationship (pseudoskeletal class III), which presents major problems for rehabilitation. This article describes the rehabilitation of a 67-year-old patient with a pseudoskeletal class III relationship. The mandible was restored with two implant-supported bar-retained overdentures using clips for retention. The extremely atrophic maxilla was restored with a combination of sinus augmentation, implant placement, and classic prosthodontic treatment using an electroformed mesostructured overdenture with swivel lock attachments on an implant-supported bar. By performing minimal augmentative and implant surgeries and using the possibilities and advantages of classic prosthetic dentistry, the clinical situation described here could be managed and the atrophic maxilla could be rehabilitated.