ABSTRACT
STATEMENT OF PROBLEM: Splinting periodontally or structurally compromised abutments is a common procedure. However, studies that investigated the effect of splinting on the accuracy of zirconia copings are lacking. PURPOSE: The purpose of this in vitro study was to evaluate the magnitude of marginal and internal gaps of zirconia copings based on the number of splinted abutments and digital scan technique. MATERIAL AND METHODS: Four maxillary acrylic resin incisors were prepared for ceramic restorations. Epoxy resin master models were fabricated by duplicating the acrylic resin model. An intraoral scanner was used to build 40 digital models (direct digital scan group [DD]); an additional 40 digital models were constructed by scanning 40 maxillary definitive casts using a laboratory scanner (indirect digital scan group [ID]). During computer-aided design, the DD and ID groups were subdivided into 4 groups; single unit (group SU); 2-unit splinted (group 2S); 3-unit splinted (group 3S), and 4-unit splinted (group 4S). Zirconia copings were then fabricated. Using the replica technique, marginal, axial, and occlusal gaps were measured and statistically evaluated (α=.05). RESULTS: In DD, group 4S exhibited larger marginal gaps than groups SU, 2S, and 3S (P<.001). In ID, group SU exhibited smaller marginal and occlusal gaps than group 4S (P<.001). Group 4S exhibited significantly greater axial gaps than groups SU, 2S, and 3S (P<.001). CONCLUSIONS: As the number of splinting units increased, the magnitude of the marginal gap tended to increase; however, the differences were less than 5 µm, which is clinically insignificant. Axial gaps in the ID group demonstrated a significant difference (>35 µm) among the groups.
Subject(s)
Dental Abutments , Denture Design , Denture, Partial, Fixed , Occlusal Splints , Dental Impression Technique , Dental Marginal Adaptation , In Vitro Techniques , Incisor , Models, Dental , ZirconiumABSTRACT
Computer-assisted design/computer-assisted manufacturing (CAD/CAM) technology has been widely used in the field of dentistry. Among CAD/CAM custom abutments, zirconia abutments are becoming more popular due to their favorable mechanical and esthetic properties. However, recent review articles show that fractured zirconia abutments are a common prosthetic complication. In this clinical report, a 72-year-old man presented with a dislodged implant-supported fixed prosthesis because of fractured zirconia abutments. This clinical report describes a successful application of CAD/CAM technology to fabricate duplicate abutments, which were retrofitted to the existing prosthesis.
Subject(s)
Computer-Aided Design , Dental Abutments , Dental Implant-Abutment Design , Dental Prosthesis Repair , Dental Prosthesis, Implant-Supported , Aged , Dental Impression Technique , Dental Marginal Adaptation , Dental Materials/chemistry , Dental Restoration Failure , Denture, Partial, Fixed , Humans , Male , Zirconium/chemistryABSTRACT
An implant that had penetrated the nasal cavity of a 53-year-old woman was removed after 10 months. The implant had a resorbable blast media surface and an external connection. Histomorphometric evaluation showed that the mean bone-implant contact ratio was 88.08%, and excellent osseointegration was observed. The mean bone fill between threads was 78.46%.
