Use Of Impression Materials Research Articles

Digital implant impression taking - an overview

In dentist's daily practice, intraoral scanning systems are increased. Besides scanning of prepared teeth, also implants could be scanned intraorally. This clinical report describes the step-by-step techniques to scan digitally intraoral implants with two intraoral scanners (Lava™ C.O.S., 3M Espe and the CEREC AC connected with inLab MC XL, Sirona) for generating implant suprastructures without the use of impression materials, dental stone or implant impression copings. Different workflows, possibilities and limits by scanning dental implants are demonstrated.

Assessing Clinical Communication for Fixed Prosthodontics Construction between Dental Laboratories and Dentists

Objective. This study aimed to estimate the communication between dental practitioners and dental technicians, through fixed prosthodontics from a dental laboratory technician's point of view, study the weak points, and try to offer them. Methods. In Tripoli, a randomized sample of private dental laboratories was chosen. A hundred and fifty questionnaires were distributed, and 130 were received (response rate=87%). A part of the questionnaires was mailed to the laboratory directors of dental laboratories and others were distributed to the dental technicians personally (face to face). The survey asked questions about the following areas of work authorization: Academic certificate, Years of work as a dental clinician, choice of materials for the prosthesis, design of the fixed prosthesis, and shade description. The use of impression materials for fixed prosthodontics was part of the questionnaire. For each question, the number of responses received was tabulated and converted to a percentage. Data were collected and analyzed statistically with (SPSS) version 25 software and Pearson’s Chi-square test p value < 0.05 was considered as statistically significant. Results. The findings showed that the telephone 42.9% and written dental prescription 24.2% are the main communication tools. The technician is more likely to choose fixed prosthesis design alone when conversing with doctors verbally or via email, while they sometimes choose it when sending them written prescriptions. Therefore, the best form of cooperation would be a written prescription. 84.6% of dental technicians received impressions in a non-disinfected state. The plastic stock tray was the most common choice of impression tray (75.4%). The minority of dental technicians 19.7% are discussing pontics design with the dentist. Conclusion. According to Tripoli dental technicians, good quality communication between both dental technologists and dentists is not always present. The connection between these two dental offices still needs work.

Survey of Impression Materials and Techniques Used in Fixed Prosthodontics among Nepalese Dentists

There is variation in fixed prosthodontics practice and many studies have concluded that clinicians definitely deviate from the recommended clinical protocols. If this happens during treatment with fixed prosthesis, the quality of fixed prostheses is compromised which affects it’s long term survival. Therefore, the aim of this study was to evaluate the use of impression materials and techniques in fixed prosthodontics among Nepalese dentists and to compare the findings on the basis of educational level and years of experience. A cross-sectional, questionnaire-based online survey was done amongst the Nepalese Dentists through google forms. Data from the completed questionnaires were analysed using the SPSS version 16. All statistical analyses were carried out at a significance level of P < 0.05. Out of 129 participants, 68 (52.7%) dentists often made diagnostic impression for fabrication of study cast. 85(65.9%) dentists used Addition silicone, 11(8.5%) used Condensation silicone and 33(25.6%) used Alginate for final impression making. Most commonly used elastomeric impression technique was Putty Wash single stage (56.2%), 40.7% used Putty Wash two stage, 3.1% used Single mix (Monophase) technique. Regarding retraction cord, 63.5% of dentists used Plain gingival retraction cord and 35.7% of dentists used Chemical impregnated retraction cord. Conclusion: The study found that most of the responses on use of impression materials and techniques were significantly associated with the level of education and clinical experience.

New era of digital impressions and computer-aided designing/computer-aided manufacturing technology in fixed dental prosthetics

Rehabilitation of in esthetic zone with fixed dental prosthesis (FDP) is the gold standard in the field of prosthodontic dentistry. Various impression materials have been used for impression making depending upon the type of prosthesis. The fabrication of FDP using conventional technique has been followed since long time. It is an elaborate and laborious procedure involving multiple steps wherein there are the chances of error incorporation in the final prosthesis. It may lead to distortion and misfit of final prosthesis. In the present era of dentistry, digitization in the form of direct metal laser sintering, computer-aided designing (CAD), and computer-aided milling, rapid prototyping has taken over many clinical and laboratory procedures to minimize or avoid the inaccuracies. Digital impressions and CAD/computer-aided manufacturing (CAM) alleviate the use of impression materials which can undergo distortion, fabrication of working models, and various other dental laboratory procedures involved in the fabrication of prosthesis. This case report describes the fabrication of FDP using digital impressions with intraoral scanner and CAD/CAM.

A movable finger Prosthesis

I cried that I had no rings, till I saw someone who had no fingers. Whether the traumatic loss of limbs or fingers is due to war, congenital malformations, systemic diseases (diabetes), industrial, domestic or vehicular accident, or amputation, it leaves the individual with a long-lasting emotional scar from the disfigurement. We as prosthodontists have the skillset to change a patient's life by making a prosthesis that would enhance a patient's physical and psychological well-being. Through time, emphasis has been made on replacing a lost digit for aesthetic purposes but function is equally important, if not more. Movement of a finger using the movement of the patient's own hand may provide the patient with adequate movement to carry out his or her daily activities. In this age of digitalization, the use of impression materials is slowly but steadily reducing. The movable finger prosthesis described in this article eliminates the need for using any impression material as well as shows the use of 3D printing to make a functional prosthesis. (Int J Maxillofac Prosthetics 2019;1:14-19)

Using digitally coded healing abutments and an intraoral scanner to fabricate implant-supported, cement-retained restorations

The accuracy of conventional impression materials and stone dies has been a consistent challenge for clinicians. As an alternative, intraoral scanning technology has the potential to resolve this problem. This clinical report describes the step-by-step technique necessary to scan digitally coded healing abutments with an intraoral scanner and generate implant abutments and cement-retained restorations without the use of impression materials, dental stone, or implant impression copings and analogs.

3D surface imaging in dentistry – what we are looking at

3D imaging has been widely used within various fields of dentistry to aid diagnosis, in treatment planning and appliance construction. Whereas traditionally this has involved the use of impression materials together with plaster or stone models, modern techniques are continually evolving which use virtual 3D images. These electronic virtual images are created using either contact or non-contact optical scanning techniques, but there are limitations, the most important of which is that any new virtual surface image is created from a series of discrete data points. It is not created from a continuous stream of data relating to the original object. This means that computer software has to be used to recreate a possible best fit, virtual surface from the data obtained. This paper describes the principles behind 3D scanning technology, the limitations of 3D imaging as well as current and possible uses of such imaging in clinical dentistry.

Viscosity of elastomeric impression materials

(1) Some elastomeric impression materials (Omniflex and Impregum) exhibited extreme shear thinning properties. This property was considered useful and these materials can be considered all-purpose. (2) The use of impression materials in syringing applications should not be precluded simply because the substances are thick or heavy during spatulation. A tenfold reduction in viscosity with increasing shear rate was found for three of the materials tested. (3) Viscosity characteristics of the impression rubbers were linked to filler content. (4) The viscosity rise during cross-linking was monitored for various impression products. It was found that each manufacturer's specifications of the length of time for syringing were relatively accurate.