XiVE® CAD/CAM Bridges (Abutment-supported/ Implant-supported) (XiCC)

A Randomized, Prospective, International, Multi-center Clinical Study to Evaluate the Peri-implant Tissue Outcome of Abutment-supported XiVE® CAD/CAM Supra-structures and Directly Implant-supported XiVE® CAD/CAM Supra-structures (Split-mouth) in Partly Edentulous Human Subjects.

This study has been designed in order to collect data with regards to the peri-implant tissue outcome of abutment-supported restoration and direct implant-fixed restoration. Therefore a small group of subjects with partly edentulous maxilla is selected to show that both techniques are efficient and safe and to show comparable peri-implant tissue outcome for both methods. At the time of impression forming for each centre treatment A (= abutment-supported XiVE® CAD/CAM supra-structure) and B (= direct implant-fixed XiVE® CAD/CAM supra-structure) is assigned to the left and right side of the maxilla by being randomized at the time of impression forming.

The planned study profile is to assess the peri-implant tissue outcome of abutment-supported restoration and direct implant-fixed restoration. Two treatments, Treatment A which is the abutment-fixed supra-structure and Treatment B, the direct implant-fixed restoration, are assessed within the scope of this clinical investigation. Treatment A: The XiVE® CAD/CAM supra-structure is fixed on abutments. The effect of platform-switching which is discussed intensely in the scientific literature is used in order to shift away the connection between implant and supra-construction (interface) from the implant edge and peri-implant tissue and towards the implant centre. However, the implant-abutment-connection area is a potential entry port for micro-organisms which have direct influence on the state of the peri-implant hard and soft tissue and consequently on the long-term prosthetic and implant success [8]. By using an abutment as a connector between implant and supra-structure implies the generation of one more micro-gap (between supra-structure and abutment) and possible retention of microbial plaque though located above the hard tissue level. Treatment B: The XiVE® CAD/CAM supra-structure is fixed directly on the implants. In contrary to treatment A, only one entry port (micro-gap) for micro-organisms exists: The interface between supra-construction and implant. So, there is one main point where the initial force has main influence on the implant and the peri-implant tissue [8-10]. Besides, this interface lies directly on the implant shoulder level and by that on the osseous level. There is no displacement of the transitional area to the implant centre. This study has been designed in order to collect data with regards to the CAD/CAM system used on the DENTSPLY Friadent implant system XiVE®. In particular, the peri-implant tissue outcome of abutment-supported restoration and direct implant-fixed restoration will be evaluated. Therefore a small group of subjects with partly edentulous jaw is selected to show that both techniques are efficient and safe and to demonstrate the non-inferiority with regards to the peri-implant tissue outcome for any of both techniques. Each subject will receive both treatments, treatment A on the one site of the maxilla and treatment B on the other. The randomization method which finally defines which subject receives one treatment on the left maxilla region and the other on the right maxilla area or vice versa is described in section 5.1. In conclusion, both treatments might have pros and cons which may affect the peri-implant tissue outcome.

After randomization one side of the jaw will be provided with a XiVE CAD/CAM bridge placed on an abutment.

After randomization one side of the jaw will be provided with a XiVE CAD/CAM bridge placed directly on an implant.

Intra-oral radiographs from implant insertion and at time for prosthesis insertion as well as from 1 and 2-year follow-up visits (calculated from the time of loading) should be taken for evaluation of bone level. All radiographs will be examined by an independent dentist. For the purpose of this examination XCP film holder (DENTSPLY Rinn, 1212 Abbott Drive, Elgin, Illinois 60123-1819, USA) are individualized for each subject and for each x-ray.

The evaluation of the sulcus fluid flow rate (SFFR) is a common method for the objective definition of the gingiva inflammation level in clinical research. The SFFR is measured with an electronic sulcus fluid hygrometer, and always as the first procedure in order not to be influenced by other investigation parameters. The hydrometer values results are generally classified in the categories healthy (0-20), slightly irritated (21-40), moderately irritated (< 100) and strongly inflamed (> 100). For this clinical investigation no absolute values, but relative values were compared. The SFFR values measured for each implant at Visit 1 were defined as "zero point-values". The respective first natural tooth in mesial direction served as control. All values obtained at the following visits for each implant were compared to the appropriate reference value (zero point).

Inclusion Criteria: Subject > 18 years. Female subject of child-bearing potential must use reliable methods of contraception. Subject has partly edentulous maxilla (free-end or large gap in posterior area on both sides). For all implants immobility and clear percussion sound is applicable. The subject is healthy and compliant with good oral hygiene. Favorable and stable occlusal relationship between the remaining teeth. Subject must be reliable, cooperative, and in the opinion of the Investigator, likely to be compliant with study procedures. Subject provides written informed consent signed and dated prior to entering the study. Implantation of XiVE® implants at least 3 months ago. XiVE® implants have been placed primary stable by considering sufficient horizontal and vertical bone dimension. Exclusion Criteria: Subject has a history of drug abuse, addiction to medication or alcohol abuse within the previous year. Subject with planned or performed head and neck radiation. Known unavailability of subject for FU Visit(s). Subject has - in the opinion of the investigator - any systemic metabolic disorder or bone disorder or is taking medication that compromises or might have compromised post-operative tissue regeneration or osseointegration. Subject has major bone defects in the implantation area. Subject is taking medication that compromises or might have compromised post-operative healing and/or osseointegration (e. g. bisphosphonates). Subject exhibits an oral infection. Subject has received any investigational drug within 30 days prior to screening. Severe bruxing. Subject has a clinically significant or unstable medical or physiological condition. Female subject is pregnant or lactating or intends to become pregnant during the course of the study. Subject is not willing to participate in the study or not able to understand the content of the study.