Comparison of two resilient attachment systems for implant-/mucosa-supported overdentures with a PEKK framework: a clinical pilot study

Abstract

Objectives The aim of the study was to determine differences between Locator and CM LOC attachment systems regarding patient satisfaction and wear of the abutments and their inserts. Plaque accumulation onto the polyetherketoneketone (PEKK) framework and polymethylmethacrylate (PMMA) was investigated for the implant-supported overdentures. Methods Seventeen edentulous patients were randomised to receive either Locator or CM LOC system for the first year. The total number of implants was 53. After the randomisation, 25 implants received Locator system, and 28 implants received CM LOC system in the first year. After a period of 12 months, the attachment system was exchanged from either Locator to CM LOC or vice versa. Oral Health Impact Profile (OHIP-14) questionnaires were used to evaluate patient satisfaction, chewing comfort, and pressure lesions. Prosthesis hygiene on the PMMA and PEKK surfaces was evaluated by using Stark plaque index. After the exchange of the abutments, they were stored until the end of the 24 months, and the surface wear of the abutments was analysed using a scanning electron microscope. Results Three patients (10 implants) died shortly before the end of the first year. Two patients (7 implants) received only Locator system since CM LOC was not indictable for their implant system. Patient’s satisfaction was increased when the attachment system was changed from Locator to CM LOC after 12 months of wearing time. Chewing ability and comfort were increased when the attachment system was changed from CM LOC to Locator after 12-month wearing time. There was no influence of the change of the attachment system on pressure lesions. The observed plaque accumulation was higher on the PMMA than on the PEKK surface. For the 8 investigated Locator abutments, the wear was within low and middle level. For the 28 investigated CM LOC abutments, the wear was within middle and high level for the terminal implants and between low and middle for the central implants (for patients who received 4 implants). Conclusions Patient’s satisfaction and wearing comfort can be improved with implant-supported overdentures with CM LOC abutments in comparison to Locator. There was no clear difference between both attachment systems concerning the chewing ability of the patients. Plaque accumulation was observed on both attachment systems in different areas. Plaque accumulation on PEKK surface was less than on PMMA surface. Clinical relevance The CM LOC attachment system offers stable and comfortable wearing conditions for implant-supported overdentures. The use of PEKK as a framework material could reduce the incidence of pressure lesions.

Prosthetic Maintenance Assessment for Two Implant-Retained Overdentures Reinforced with PEKK versus Co-Cr Framework: A Randomized Controlled Clinical Trial

“…Teeth separation was signi cant in group (II); which can be attributed to the increased thickness of the PEKK framework, as suggested by prior research. This increased thickness resulted in a reduced remaining space for acrylic resin and teeth, likely contributing to the observed teeth separation [21,24,25,30].…”

“…All undercuts were blocked on the virtual model. The desired framework was outlined and placed in the virtual model to cover the crest of the ridge with space over the metal housings and with 1mm and 2mm thickness for the Co-Cr and PEKK frameworks, respectively according to the recommended minimum thickness of each from the previous studies [24,25]. Finally, a 2mm relief was designed under the frameworks, and then it was checked and smoothened from all surfaces.…”

Clinical, Radiographic, and Prosthetic Outcomes of Poly Ether Ether Ketone (PEEK) Versus Poly Ether Ketone Ketone (PEKK) Frameworks in Mandibular Fixed-Detachable Implant-Supported Prosthesis: A Randomized Clinical Trial

“…Accordingly, the successful clinical performance of the PEEK and PEKK as framework materials in implant supported prostheses individually is reported in the current study. This higher success was documented in limited clinical studies 32,22,[40][41][42][43][44][45][46][47][48][49][50] and scarce invitro studies that compared the PEEK to PEKK 12,26,35 . The superior biomechanical properties of both materials encouraged their use in implant screw retained prosthesis.…”

“…Almost all these randomized clinical trials compared metal alloys to PEEK as a framework material [40][41][42][43][44][45][46] . Despite the versatility in manufacturing PEKK and its rising popularity, rare studies explored the clinical performance of PEKK and most of them were case reports 32,[47][48][49][50] . Almost all studies comparing PEEK to PEKK were invitro studies 12,13,17,23,26,35 .…”

Retentive Behavior of Locator versus Ball Attachments on Parallel versus Non-Parallel Implants

“…Implant-retained overdentures have been repeatedly shown to increase patients' satisfaction and wearing comfort [1] while at the same time showing a high survival rate regardless of the specific attachment system used [2]. In order to keep treatment costs low, prefabricated components are often employed, for which prosthesis fractures [3,4] and loss of retention due to wear of the attachment system [5,6] constitute frequently observed complications.…”