Journal of Oral Implantology April 2014 - (Page 137)

RESEARCH Evaluation of Accuracy of Casts of Multiple Internal Connection Implant Prosthesis Obtained From Different Impression Materials and Techniques: An In Vitro Study Malesh Pujari1* Pooja Garg2 D. R. Prithviraj, MDS3 Movement of impression copings inside the impression material using a direct (open tray) impression technique during clinical and laboratory phases may cause inaccuracy in transferring the 3-dimensional spatial orientation of implants intraorally to the cast. Consequently, the prosthesis may require corrective procedures. This in vitro study evaluated the accuracy of 3 different impression techniques using polyether and vinyl polysiloxane (VPS) impression material to obtain a precise cast for multiple internal connection implants. A reference acrylic resin model with 4 internal connection implants was fabricated. Impressions of the reference model were made using 3 different techniques and 2 different impression materials. The study consisted of 24 specimens divided into 6 groups of 4 each. Impressions were poured with ADA type IV stone (Kalrock, Kalabhai Karson Pvt Ltd, Mumbai, India). All casts were evaluated for the positional accuracy (mm) of the implant replica heads using a profile projector. These measurements were compared to the measurements calculated on the reference resin model, which served as a control. Data were analyzed with 2-way analysis of variance (ANOVA) followed by Bonferroni multiple comparison procedures to evaluate group means. The results revealed significant difference for anterior implant distance between the 2 impression materials (P , .01) and also among the 3 different techniques (P , .05). The lowest mean variation was found with the polyether impression material and the splinted technique. For posterior implants, the results suggested no significant difference between the 2 impression materials (P ! .05). Although results were not statistically significant, the polyether impression material showed the lowest mean variation as compared to the VPS impression material. However, there was a significant difference among the 3 different techniques (P , .05). Among the 3 different techniques, the lowest mean variation between 2 posterior implants was found in the splinted technique. Casts obtained from impression techniques using square impression copings splinted together with autopolymerizing acrylic resin prior to the impression procedure were more accurate than casts obtained from impressions with nonmodified implant impression copings and with airborne particle-abraded, adhesive-coated copings. Casts obtained from polyether impression material were more accurate than casts obtained from vinyl polysiloxane impression material. Key Words: dental implants, implant impression techniques, pick-up impression technique, transfer impression technique INTRODUCTION 1 Department of Prosthodontics and Implantology, Pandit Deendayal Upadhyaya Dental College and Hospital, Solapur, India. 2 Panipat, Haryana, India. 3 Department of Prosthodontics and Implantology, Government Dental College and Research Institute, Bangalore, India. * Corresponding author, e-mail: maleshpujari@gmail.com DOI: 10.1563/AAID-JOI-D-10-00207 I mpression techniques and materials used in dentistry have come a long way since the early times, when it was just an attempt to record the tissues without the knowledge and appreciation of the anatomy and physiology Journal of Oral Implantology 137

Table of Contents for the Digital Edition of Journal of Oral Implantology April 2014

Consolidated Standards of Reporting Trials (CONSORT): Answering the Call for JOI’s Endorsement
Photoelastic Analysis of Stress Distribution With Different Implant Systems
Influence of Abutment Screw Design and Surface Coating on the Bending Flexural Strength of the Implant Set
Comparison of Implant-Abutment Interface Misfits After Casting and Soldering Procedures
Evaluation of Accuracy of Casts of Multiple Internal Connection Implant Prosthesis Obtained From Different Impression Materials and Techniques: An In Vitro Study
The Effect of Different Implant-Abutment Connections on Screw Joint Stability
Effects of pH and Elevated Glucose Levels on the Electrochemical Behavior of Dental Implants
Finite Element Analysis of Provisional Structures of Implant-Supported Complete Prostheses
Saliva Versus Peri-implant Inflammation: Quantification of IL-1b in Partially and Totally Edentulous Patients
Heat Generated During Seating of Dental Implant Fixtures
An Alternative Approach for Augmenting the Anterior Maxilla Using Autogenous Free Gingival Bone Graft for Implant Retained Prosthesis
Nasopalatine Duct Cyst, a Delayed Complication to Successful Dental Implant Placement: Diagnosis and Surgical Management
The Custom Endosteal Implant: Histology and Case Report of a Retrieved Maxillary Custom Osseous-Integrated Implant Nine Years in Service
Occlusal Concepts Application in Resolving Implant Prosthetic Failure: Case Report
Three-Year Follow-Up of a Single Immediate Implant Placed in an Infected Area: A New Approach for Harvesting Autogenous Symphysis Graft
Use of Stress Analysis Methods to Evaluate the Biomechanics of Oral Rehabilitation With Implants

Journal of Oral Implantology April 2014