To cord or not to cord? That is still a question

Dentists' knowledge and preference regarding gingival displacement methods

INTRODUCTION

An accurate impression is an essential procedure for fabricating indirect fixed restorations. To achieve a precise final impression, the management of gingival tissue is without doubt a crucial.

AIM

To evaluate the use of different gingival displacement techniques among dental clinicians and to assess their associated knowledge and technique preferences.

METHODS

A self-designed survey was created electronically and sent to a list of dentists. The survey was composed of multiple sections. Participants who stated that they do not use GD methods were asked to answer the survey questions based on their knowledge. Descriptive statistics were generated, andChi-square test was used to examine the association between the different variables.

RESULTS

A total of 188 dentists participated in this study. The majority 144 (76.6%) use GD in their practice. When asked which technique yields a more accurate impression with lower incidence of repeating the impression, 93 (64.6%) reported retraction cord technique with a hemostatic agent results in a higher impression accuracy, while only 14 (9.7%) declared the retraction paste technique as being more accurate.

CONCLUSION

The cordless GD technique is believed to be easier, faster, and less traumatic to the gingival tissues, nevertheless, the outcome of dental impressions is believed to be more predictable with the use of conventional retraction cords and hemostatic medicaments.

Atraumatic intraoral scans and virtual hybrid casts for custom implant abutments and zirconia implants: Accuracy of the workflow

STATEMENT OF PROBLEM

Making impressions of 2-piece implants is typically associated with the repeated disassembly and reassembly of superstructures and related to soft-tissue trauma. Intraoral scanning of 1-piece zirconia implants is problematic because scan bodies are not readily available. Whether using virtual hybrid casts generated by merging intraoral scan data with the known surface geometry of abutments can solve these difficulties is not clear because data on accuracy of the workflow are sparse.

PURPOSE

The purpose of this in vitro study was to evaluate the accuracy of virtual hybrid casts with respect to the impact of different gingival situations. The workflow was designed to render pointless the use of impression posts and scan bodies and avoid any displacement of the gingiva.

MATERIAL AND METHODS

The mandibular right first molar in a typodont was replaced with a 2-piece titanium implant with a custom abutment and then a 1-piece zirconia implant. Three situations representing different gingival heights covering the abutments were simulated. Twelve intraoral scans were made for each situation to capture the recordable parts of the abutments, and virtual hybrid casts were constructed by superimposing and merging the intraoral scan data with the original laboratory scan data of the abutments. Hybrid casts were compared with reference data by using the root mean square error. Scan body-related and cast scan-related protocols were performed representing conventional digital workflows. Statistical analysis with the Kolmogorov-Smirnov, Kruskal-Wallis, and Mann-Whitney U tests with the Bonferroni correction was conducted with a statistical software program (α=.05).

RESULTS

Deviation was low in the hybrid casts of the custom abutment when the entire abutment was recorded (6.5 μm; IQR: 3.0 μm), when the preparation margin was disguised (7.0 μm; IQR: 1.0 μm), and when half of the abutment was covered (8.0 μm; IQR: 4.0 μm). The accuracy in the 1-piece zirconia implant was 10.0 μm (IQR: 4.0 μm) when the whole surface of the abutment was visible and 12.5 μm (IQR: 6.0 μm) when the preparation margin was covered. When only half of the abutment was captured, a larger deviation of 22.0 μm (IQR: 7.0 μm) was observed. The hybrid cast concept demonstrated superior accuracy compared with protocols using scan bodies (76.0 μm; IQR: 27.0 μm) and cast scans (23.0 μm; IQR: 15.0 μm).

CONCLUSIONS

Digital intraoral scanning and the generation of virtual hybrid casts provide high accuracy and are suitable for the fabrication of single-implant-supported restorations. The atraumatic procedure avoids tissue manipulation and reduces clinical effort.

Dentists’ Knowledge and Preference Regarding Mechanical Gingival Displacement Methods.. [DOI: 10.21203/rs.3.rs-2668816/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Introduction. An accurate impression is an essential procedure for fabricating indirect fixed restorations. To achieve an accurate dental impression, the management of gingival tissue is an important step. Aim. To evaluate the use of different gingival displacement techniques among group of dental clinicians and the associated knowledge and technique preferences. Methods. A self-designed survey was created electronically and sent to a list of dentists. The survey was composed of multiple sections. Participants who stated that they do not use GD methods were asked to answer the survey questions based on their knowledge. Descriptive statistics were generated, and the Chi-square test was used to examine associations between the different variables. Results. A total of 188 dentists participated in this study. The majority (76.6%) use GD in their clinics. When asked which technique yields a more accurate impression and a lower incidence of repeating the impression, 64.6% reported that the technique is retraction cords with a hemostatic agent, and only 9.7% said it was retraction paste. Conclusion. The cordless GD technique is believed to be easier, faster, and less traumatic to the gingival tissues, nevertheless, the outcome of dental impressions is believed to be more predictable with the use of conventional retraction cords and hemostatic medicaments.

Evidence-based prosthodontics

The practice of evidence-based dentistry has assumed an integral part in today's world. It allows us to achieve self-motivated, problem-based learning, which eventually leads to acquiring clinically sound and relevant information that has a strong backing of evidence on a scientific basis. This would enhance the diagnosis but also the prognoses and treatment that are administered with the highest of ethical standards. Due to the advancement in material studies, dentistry, especially prosthodontics, is getting more intricate and complex due to the dynamic state in the development of new dental materials and equipment. The best evidence is sought through vast empirical literature consisting of controlled trials and reviews. Modern clinical practice should be concurrent with the latest scientific evidence that brings high standards to the treatment options and patient's values. This review highlights the evidence based dentistry on prosthodontics while also addressing the issues it poses in modern day dental practice.

Digital Tissue Preservation Concept: A Workflow for Guided Immediate Implant Placement and Restoration

The digital workflow presented here allows for fabrication and placement of a definitive custom abutment at the time of tooth extraction and guided immediate implant placement, thus preserving soft tissue anatomy. Since abutment design was based on the shape of the original tooth, it represented a de facto emergence-analog that provided ideal soft tissue support. The approach of superposing and merging of custom abutment design data with data captured intraorally after abutment placement enabled a digital impression without gingival displacement and associated trauma. The generated data facilitated the fabrication of a precisely fitting restoration concurrent with the implant healing period.