#Full-Arch 15. Feb 2024

Enhancing Quality of Life: Successful Transition from LOCATOR® Overdenture to LOCATOR FIXED® Prosthesis

by Michael Scherer, USA

The introduction of dental implants, which provide support for various type of prostheses, marked a significant breakthrough in the field of oral rehabilitation. Implant-supported overdentures have historically represented a commendable solution, offering patients heightened stability and functionality[1, 2]. However, contemporary demands for fixed oral rehabilitation and reduced costs have emerged, and as a result, innovative treatment modalities, among them being the LOCATOR FIXED® system, have been developed.

The LOCATOR FIXED® system is a novel fixed full-arch treatment approach that shares the foundational abutments and workflow with the established LOCATOR® Removable attachment system. The key departure lies in the utilization of rigid inserts and a distinctive high-retention gold housing, differentiating it from the flexible nylon insert and silver housing characteristic of the removable solution3.

The following clinical case report highlights the seamless transition facilitated by LOCATOR FIXED®, allowing patients with existing LOCATOR® Removable overdentures to effortlessly adopt a permanent fixed prosthesis. Beyond the technical aspects, it's noteworthy that this transition significantly contributes to an enhanced quality of life for patients, particularly those with financial constraints4. In our practice, we have experienced that an improved permanence and functionality of a fixed prosthesis positively impact patients' daily lives, offering a lasting solution that aligns with their financial considerations.

Initial situation

A systemically healthy 55-year-old woman arrived at our clinic expressing her primary concern, stating: "Doctor, I appreciate my overdenture, but I would love to have one I don’t have to remove.” From our clinical experience, patients often convey a nuanced sentiment, expressing modest satisfaction while subtly indicating a desire for further improvement in the quality of life.

According to her dental history, the patient was treated with a maxillary overdenture several years prior to the recent appointment. The prosthesis was supported by four implants located in the first molar and canine regions.

The extraoral assessment revealed a prosthesis in a modest condition (Fig. 1).

The intraoral assessment showed an overdenture prosthesis with a traditional processed denture tooth on top of a metal framework with minimal palatal coverage (Fig. 2).

Following the removal of the overdenture, the LOCATOR® abutments were appreciated on the dental implants. The oral hygiene was good and presented healthy peri-implant tissues (Fig. 3).

Treatment planning

Upon the patient's request for a permanent solution, we proposed the initial option of a screw-retained prosthesis. Unfortunately, the associated expenses for this particular prosthetic alternative proved to be beyond the patient's financial means. Therefore, we presented her with the LOCATOR FIXED® concept, suggesting that this option could help maintain lower clinical fees and costs. She expressed enthusiasm about the simplicity of utilizing the same implants and abutments she currently had.

Preparation and patient selection play a crucial role in achieving highly aesthetic treatment outcomes with LOCATOR FIXED®. These include an adequate distribution of the implants cross-arch, as well as sufficient vertical space for a structurally sound prosthesis. Since the proper selection of the abutment height is imperative when pre-planning a case, we made sure the prosthesis was not sitting above the tissue and carefully chose the restorative material.

The treatment workflow included:

  1. LOCATOR® scan bodies placed onto each abutment.
  2. Digital impressions with 3Shape TRIOS intraoral scanner.
  3. Fabrication of the new prosthesis.
  4. Delivery of prosthesis.
  5. Recall appointments at 6-month intervals. 

Prosthetic procedures

Following the placement of the LOCATOR® Scanbody on each LOCATOR® Abutment, we made sure that the seating surfaces of the abutments were dry and free of residue. Next, digital impressions of the maxillary arch were made using a 3Shape TRIOS intraoral scanner (Figs. 4,5).



Afterward, the mandibular opposing dentition and occlusion with the prosthesis were also scanned (Fig. 6). Special emphasis was placed on capturing the maxillary arch with the palatal soft tissues to allow optimal digital registrations in the laboratory (Fig. 7).

The optical scan files, accompanied by instructions, were sent to the dental laboratory for the production of a fixed full-arch prosthesis designed for LOCATOR FIXED®.

The 3Shape Dental System software was employed by the dental laboratory for the design of a two-piece maxillary prosthesis (Fig. 8). This restoration was meticulously fabricated, employing a two-piece fiber-composite framework onto which nanoceramic resin teeth were delicately bonded using luting techniques (Fig. 9). Furthermore, within the dental lab, the LOCATOR FIXED® housings were integrated into the maxillary prosthesis.

Ten days later, the patient returned to our practice, and the overdenture was removed. The full-arch LOCATOR FIXED® prosthesis was placed and evaluated with processing inserts inside of the fixed housings. Following our protocol, we evaluated the patient’s midline, occlusion, vertical dimension, and tooth shade, which were correct prior to placing the definitive fixed inserts.

The next steps in the procedure involved the removal of processing inserts, followed by the placement of 4-unit green-colored LOCATOR FIXED® inserts into each housing within the prosthesis (Fig. 10). Subsequently, the LOCATOR® abutments underwent meticulous cleaning using an intraoral syringe, involving generous irrigation and subsequent air drying.

Once prepared, the prosthesis was positioned onto the edentulous ridge and adapted to the LOCATOR® abutments. Applying firm pressure, the prosthesis was carefully seated onto the implants and abutments. To ensure a secure fit, the seating and removal tool were engaged above each abutment, producing an audible click to confirm full engagement. The comprehensive adaptation was further verified through a radiograph, confirming the success of the procedure.

Treatment outcomes

The final prosthesis brought great satisfaction to the patient (Figs. 11,12). She undergoes follow-up visits every six months, including prosthesis removal and cleaning. At every appointment, she expresses her delight with the treatment outcome.

Author’s testimonial

Including LOCATOR FIXED® in my practice is an invaluable addition, akin to another versatile tool in my toolbox. Providing full-arch fixed prosthetic solutions at a reasonable cost expands my capacity to offer comprehensive dental treatment to a broader range of patients. The ability to seamlessly transition between removable and fixed options by merely changing inserts and utilizing LOCATOR FIXED® housings adds a transformative element. I've noted in my patients that the ease of prosthesis removal contributes to superior hygiene practices and long-term periodontal health.

References:

  1. Thomason J.M., Kelly S.A., Bendkowski A., Ellis J.S. Two implant retained overdentures--a review of the literature supporting the McGill and York consensus statements. J. Dent. 2012;40:22–34. 
  2. Jemt T, Chai J, Harnett J, Heath MR, Hutton JE, Johns RB, McKenna S. A 5-year prospective multicenter follow-up report on overdentures supported by osseointegrated implants. Int J Oral Maxillofac Implants. 1996;11(3):291-298.
  3. Buttke TM, Shahmiri R, Li Y, Swain MV. Overdenture attachment selection and the loading of implant and denture-bearing area. J Prosthet Dent. 2014;111(6):494-502. 
  4. Alsabeeha NH, Swain MV, Payne AG. Attachment systems for mandibular single-implant overdentures: an in vitro retention force investigation on different designs. Int J Prosthodont. 2011;24(3):204-207.