Jülide Özen

Early Detection of Alterations in the Resonance Frequency Assessment of Oral Implant Stability on Various Bone Types: A Clinical Study

This study was undertaken to evaluate the relation between bone quality and alterations of implant stability quotient values measured during the initial phase of healing. Nineteen patients treated with 106 implants were included in the current study. The mean bone density of the implant recipient area was measured using Simplant 11 software incorporated in the computerized tomography (CT) machine. Mean bone density measurements were recorded in Hounsfield units. The implant recipient sites were subdivided into 5 groups according to bone quality. The numbers of the structures on the recipient site belonging to D1 and D5 types showed no statistical significance and were excluded. Standard 2-stage surgical technique was utilized to prepare the surgical sites. The implant stability quotient (ISQ) value at implant placement was recorded and did not influence the treatment procedure. The ISQ was measured by an Osstell instrument. The ISQ was further registered on the 21st and 60th days. SPSS statistical software was used for the statistical analysis. In comparison with the time of insertion, the mean values of the ISQ were decreasing for the first 21 days. However, on subsequent days, the ISQ values of all bone types have increased and on the 60th day reached the values recorded at the time of insertion. Analysis of the relation between changes in stability and bone type does not reveal statistical significance. With knowledge of the current clinical study, it can be concluded that bone quality in the recipient bone site does not effect changes in implant stability at the early stages of the osseointegration process.

Rehabilitation With an Implant-Supported Metal-Acrylic Fixed Prosthesis After Ameloblastoma Resection in Mandible: Clinical Case Letter

D ue to the quality of the soft and hard tissue of the reconstructed site, the esthetic and functional rehabilitation of jaw resection patients is among the greatest of challenges for surgeons and prosthodontists. Patients may have improved oral function after receiving dental implants in resected and reconstructed sites; these implants can provide the sufficient support, stability, and retention for prosthodontic rehabilitation. There are various types of prostheses, including fixed, hybrid, or overdentures with retainers. Intra-arch distance is the primary factor that determines the type of prosthesis. The original design of fixed removable prosthesis using the 2-stage endosseous implant system was developed by Branemark. Generally, the fixed removable prosthesis resembles a flangeless denture that is retained by several osseointegrated implants and referred to as hybrid prosthesis. The prosthesis is composed of a metal framework/substructure that it is covered by resin teeth and is screwed onto implants. There is no contact between the prosthesis and the tissues of the alveolar ridge. There are some clinical conditions for which an implantsupported hybrid prosthesis may be preferred, including in cases with increased intra-arch distance, a decreased need for soft tissue support, those with limited financial resources, or patient preference. According to these conditions, a review of the literature reveals that there are multiple diverse methods regarding framework design in implant-supported hybrid prosthesis. Frameworks have been fabricated according to the following criteria: bulk for strength, adequate access for oral hygiene procedures, and strategic thinning of implant frameworks to allow for retention of acrylic resin denture teeth and denture bases. The use of computer-aided design/computeraided manufacturing (CAD/CAM) allows improvement in the accuracy of prosthetic frameworks and potentially greater success with implant-supported hybrid prosthesis. CAD/ CAM technologies have also eliminated conventional waxing, casting, and finishing procedures; in addition, the deficiency associated with these procedures has also been eliminated. With the advent of CAD/CAM protocols, milled titanium frameworks have become quite popular in implant prosthodontics. The original treatment protocol includes the fabrication of cast metal frameworks that fit accurately on restorative platforms, abutments, and/or endosseous implants. Titanium bar-shaped frameworks may also be designed to splint implants together; it has been reported that these provide retention and support for the functional and esthetic portions of the fixed hybrid prosthesis. Although there are a number of studies reporting procedures for the prosthetic rehabilitation of mandibular discontinuity defects, there is limited data on implantsupported CAD/CAM-manufactured partially hybrid prosthesis for the management of jaw defects. Therefore, this clinical case aimed to describe the rehabilitation of a patient with an implant-supported, screw-retained hybrid prosthesis fabricated on a CAD/CAM titanium framework after undergoing a partial mandibular resection and reconstruction with an autogenous iliac graft, which was subsequent to treatment for ameloblastoma.