Lithium Disilicate (CAD/CAM) Fixed Partial Dentures (FPD) Clinical Study

Clinical Evaluation of Chairside Computer Assisted Design/Computer Assisted Machining (CAD/CAM) Lithium Disilicate Fixed Partial Dentures (FPD)

This investigation will be a clinical trial to study the performance of a high strength ceramic material for bridges to replace missing teeth. The ceramic material has been approved by the FDA for patient treatment. A computer technique will be used to make the bridges. The bridges will be cemented using an adhesive resin cement (MultiLink Automix/Ivoclar). The bridges are planned be evaluated for clinical performance at 6 months, 1 year, 2 years, 3 years, and if funding permits, 4 years, and 5 years. The purpose of the study is to measure how well the high strength bridges function over an extended period of time.

The study will be composed of 30 bridges placed in adult patients that have been identified as requiring replacement of a single tooth. All the bridges will be made from the same high strength ceramic material (emaxCAD/Ivoclar) using a computer to make the entire bridge. All the crowns will be cemented using the most current marketed version of the manufacturer's adhesive resin cement (MultiLink Automix/Ivoclar). At each recall appointment an evaluation of the bridge will be completed as well as clinical photographs, an intraoral digital scan, and impression of the bridge. The purpose of the study is to measure how well the high strength bridges function over an extended period of time.

Inclusion Criteria:

• missing one anterior or premolar tooth that is appropriate for replacement with a bridge. The second premolar tooth will be the most distal tooth acceptable as a pontic for inclusion in the study.
• healthy periodontal status for the adjacent abutment teeth with 1:1 crown:root ratio
• abutment teeth must be asymptomatic prior to treatment
• Endodontically treated teeth will be acceptable for abutments as long as nonmetallic cores can be placed to retain the FPD since the lithium disilicate will be bonded to the abutments.
• no more than one bridge will be placed per patient. If a patient presents with more than one missing teeth acceptable for the study, premolar teeth will be included prior to anterior teeth. Each bridge will be three units and include only one missing tooth.

Exclusion Criteria:

• sensitive abutment teeth
• teeth with a history of direct or indirect pulp capping procedures
• patients with significant untreated dental disease to include periodontitis and caries
• pregnant or lactating women
• patients with allergies to any material in the study
• patients unable to return for recall appointments