Impressions in implant dentistry

Dimensional accuracy of vinyl polyether and polyvinyl siloxane impression materials in direct implant impression technique for multiple dental implants

Purpose:

The present study compared the dimensional accuracy of vinyl polyether silicone (VPES) and polyvinyl siloxane (PVS) impression materials used for non-splinted (NS) and splinted (S) direct open-tray impression techniques for multiple implants inserted in simulated edentulous mandibles.

Materials and methods:

A mandibular stainless steel model with eight internal connections for implant analogs was fabricated to simulate a clinical scenario. The acrylic resin splinted and non-splinted direct impressions were obtained for both VPES and PVS materials. Seventy-two cast samples were divided into four groups based on the impression techniques and materials used. The dimensional accuracies of the casts were measured in three different axes using a computerized coordinate measuring machine (CMM), and were statistically compared.

Results:

The differences in the distortion values between the VPES and PVS impression materials were not statistically significant. Similarly, the differences between the splinted and non-splinted groups among the VPES and PVS materials were not statistically significant.

Conclusion:

The casts fabricated from VPS or PVS impression materials provide similar dimensional accuracy regardless of the implant splinting method.

Knowledge, Attitude, and Practice toward Impression Technique and Materials for Recording Impression in Implant Placement among Dental Practitioners in Patna City, Bihar

Objectives:

The present study is conducted to explore the knowledge, attitude, and practice towards impression technique and materials for recording impression in implant placement among general dental practitioners.

Materials and Methods:

The present study is a cross-sectional questionnaire study. The study was conducted among general dental practitioners in Patna city in November–December 2017. Patna city was divided into five directions, which are north, south, east, west, and central. From each direction, 20 clinics were selected randomly, and dental practitioners from there clinics were interviewed. A closed-ended questionnaire consists of 19 items was prepared, the questionnaire was divided into four parts.

Results:

Majority of study participants (58 [34%]) were above the age of 40 years. 96 (56%) of study participants were male. Most of the study participants (89 [50%]) were having MDS degree. Knowledge, attitude, and behavior scores among study participants. About 43% of study participants have good knowledge scores regarding impression technique and material in implant placement while 50% of study participants had fair attitude score. About 58% of study participants had fair practice score. There was statistically significant correlation (P ≤ 0.05*) between knowledge and attitude of study participants.

Conclusion:

It was concluded that there was good knowledge, fair attitude, and practice among the dental professionals regarding the impression technique and materials for recording impression in implant placement. There was statistically significant correlation between knowledge and attitude of study participants. There was statistically significant correlation between some demographic variables and knowledge, attitude, and practice of study participants.

Implant retention systems for implant-retained overdentures

Implant retained overdentures are being increasingly utilised in both general and specialist practice to rehabilitate patients with missing teeth, particularly those that are edentate. This article aims to inform the reader of a variety of retention systems that are available to retain an implant overdenture and to understand how these systems work, their advantages and disadvantages and to outline some of the clinical and treatment planning considerations involved in selecting the most appropriate retention system for patients.

Collaboration Patterns and Processes Between Dentists and Dental Laboratories When Planning and Fabricating Implant-Supported Restorations

INTRODUCTION

The success of implant-supported restorations is dependent on proper treatment planning, effective communication within the clinical team, and the use of appropriate methods and materials in the dental laboratory. The objective of this study was to determine collaboration trends between dentists and laboratories and to assess the common methods and materials involved in fabricating implant-supported restorations.

METHODS

Questionnaires were distributed to dental laboratories and technicians. Seventy questionnaires were answered and were included in the data analyses.

RESULTS

Most of the impressions (87%) were taken using an individual custom-made open tray. In 83% of impressions, screw-retained transfer units were used, and in 61% of cases, the units were splinted. Bite registration was recorded in 91% of the cases. In 80% of cases, articulator setup was done. When matching the shade of a restoration in the anterior, 57% of the technicians do so in collaboration with the dentist, and 39% match the shade independently. Type of restoration and abutment selection were done mainly by the technicians. Abutment selection was reported to be carried out by 72% of the technicians.

CONCLUSIONS

Generally, dentists and technicians follow the standards recommended in the contemporary literature, especially, in major procedures such as impression taking, bite registration, and articulator setup. However, principal decisions, such as abutment and color shade are done mainly by technicians.

Consequences of experience and specialist training on the fabrication of implant-supported prostheses: A survey

STATEMENT OF PROBLEM

Fabricating fixed restorations on implants requires that dentists stay up-to-date with the scientific publications.

MATERIAL AND METHODS

A questionnaire containing 29 questions was sent to dentists, members of the Israeli Society of Prosthodontics, and university faculty members. Differences were evaluated using the chi-square and Fisher exact tests and Mann-Whitney U and Wilcoxon tests for questions enquiring into the frequency of use of certain methods (α=.05).

RESULTS

A total of 155 questionnaires were completed by 84 general dental practitioners and 71 specialists and residents. Statistical differences (P<.05) were found in the course of the fabrication of the implant-supported prostheses in the diagnostic waxing, trial restoration, and impression-making processes. Trial restorations were often used by residents and specialists before starting an esthetic restoration. Diagnostic waxing was used when treating patients with complex esthetic needs, mainly by prosthodontists (P=.019). A custom tray for impression making was used more by residents and specialists than by general dental practitioners (P<.001). The open tray technique for impression making of single or up to 3 implants was performed mainly by residents, specialists, and general dental practitioners with professional experience of fewer than 15 years. General dental practitioners used primarily plastic or metal trays for impression making.

CONCLUSIONS

Significantly, impression techniques and the use of custom open trays, diagnostic waxing, and trial restorations were performed by residents, specialists, and dentists with fewer than 15 years of experience.