Comparative evaluation of bioactive glass (putty) and platelet rich fibrin in treating furcation defects. Biswas S, Sambashivaiah S, Kulal R, Bilichodmath S, Kurtzman GM. Journal of Oral Implantology Vol 17(5): 411-415 This article will attempt to clarify some of the areas of confusion regarding impression materials and techniques. Attempting to prepare a tooth with a taper (even a very small one) will leave you with an over-tapered preparation. Smooth outline Additionally an end-cutting only bur is brilliant for smoothing steps along the margin. Prosthodontips for an excellent crown preparation Prep for the crown you want, not the tooth you have This is further complicated by the fact that many commercial laboratories employ plastic, disposable articulators to use in the fabrication process, adding to the inaccuracies that can occur. Evaluation of the 6 most popular plastic, disposable articulator systems used with dual-arch impressions found that with all systems, it was virtually impossible to maintain and repeat a centric occlusal position stop. The conclusion was that they should only be used for single units, not when the terminal unit in the arch is being prepared. 1

This guide will provide information about digital impressions and scanning within dentistry, including their roles, comparisons between new and traditional techniques and the benefits they offer to dentists and dental patients.A cookie set by YouTube to measure bandwidth that determines whether the user gets the new or old player interface. Ceyhan JA, Johnson GH, Lepe X. The effect of tray selection, viscosity of impression material, and sequence of pour on the accuracy of dies made from dual-arch impressions. J Prosthet Dent. 2003;90:143-149. Wadhwani CP, Johnson GH, Lepe X, et al. Accuracy of newly formulated fast-setting elastomeric impression materials. J Prosthet Dent. 2005;93:530-539. Comparative evaluation of bioactive glass putty and platelet rich fibrin in the treatment of human periodontal intrabony defects: a randomized control trial. Naqvi A, Gopalakrishnan D, Bhasin MT, Sharma, N, Haider K, Martande S. J of Clinical and Diagnostic Research 2017 Jul, Vol-11(7): ZC09-ZC13. Generally, polyether and VPS impression materials are suitable for making impressions of natural teeth and implants. Due to the higher initial hydrophilicity and constant flow behavior of polyethers, they may show a superior reproduction of the relevant details, especially in more complex cases where extra working time is needed. Based on this assumption, they are often preferred in clinically challenging situations and recommended for implant cases with multiple units. Our recommendation is that if a VPS impression material is used, the clinician should select a product, which is hydrophilic already in the unset state and offers good flow properties; e.g. 3M™ Imprint™ 4 VPS Impression Material.

Horowitz RA, Leventis MD, Rohrer MD, Prasad HS. Bone grafting: history, rationale, and selection of materials and techniques. Compend Contin Educ Dent. 2014;35(4 Suppl):1-6. Ideally, the impression material should flow freely and wet the tissue as it is being injected to achieve adaptation, and then resist flow away from the intended surface areas. The same procedure will facilitate spreading of heavy-body material on the impression tray and retain it in the tray. This phenomenon is called shear thinning ( Chapter 3). Essentially, a stress-thinning material becomes less viscous when stressed as during injection and then recovers its viscosity when it rests on the tissue or or in the tray. All elastomeric impression materials exhibit shear-thinning characteristics before setting. Many dental offices now have the ability to take digital dental impressions. During this procedure, your healthcare provider uses a digital handheld wand to capture thousands of pictures of your teeth and gums. As your healthcare provider passes the wand over your teeth, images of your mouth will come up on a computer screen. Next, the computer software will stitch the images together, creating a digital, 3D representation of your dental arches. There’s no need for putty when taking digital dental impressions. Prepare teeth with a new, or nearly new bur. This will make the cutting more efficient, reduce appointment times, and reduce the heat you transmit to the pulp, reducing the risk of pulpal complications. Good retraction and good vision

Features of a perfect crown preparation

Clinical and cone beam computed tomography comparison of NovaBone Dental Putty and PerioGlas in the treatment of mandibular class II furcations. Asmita, Gupta V, Bains VK, Singh GP, Jhingran R., Indian J Dent Res, 2014 25(2):166-73. The putty/wash techniques fall into 2 basic categories: (1) a single-step procedure where the putty is loaded into the tray and inserted immediately after syringing a wash material around the prepared tooth or teeth, or (2) a 2-step procedure where the putty is used to take an impression before starting the preparation, allowed to set, and removed from the mouth. After tooth preparation is complete, the tooth has a wash material syringed over it, and the initial tray and putty impression are reinserted over the wash. Variations of this include routing out part of the putty impression around the prepared tooth to produce space for the wash, and relining the entire impression with wash material. A colleague recently pointed out that it is appropriate to change terminology from gingival retraction to the more correct sulcus expansion. Gingival retraction, which may have been a more viable term in years past when a patient’s tissue health might have been less than ideal, is no longer descriptive of the procedure that is actually performed. When a patient has good gingival health—and there should be no reason to begin an indirect restoration until that has been achieved—the procedure that is accomplished is a temporary expansion of the sulcus to permit access for final preparation of the margin and then taking the impression. Removing the cords after completing the impression then permits the tissue to return to its normal biological position without a change in the occlusal-apical height of the tissue. Changing the terminology helps the dentist, chairside assistant, and patient more accurately visualize and then achieve the ideal result. Dentistry is evolving and advancing at a rapid pace and traditional methods are being replaced by new and innovative technology. The introduction of new technology often improves accuracy and efficacy of treatment, reduces time in the dental chair, increases cost-effectiveness and makes the process less stressful and time-consuming for both the patient and the dentist. Digital impressions Polysiliconteeth impression material is one of the most precise materials. It is a polymer synthetic rubber putty and an elastic irreversibleimpressionmaterial. It has good elasticity, toughness and strength, and the precision of the teeth impressionis high. It has good chemical stability and easy demoulding. It is an ideal impression material at present.

After the impression material has completely solidified, gently tilt the tray to dislocate the impression and then rotate the tray out of the mouth. Avoid violent use when removing the impression, avoid excessively tilting the tray, to avoid deformation of the tray and the impression, or to release the impression material, to avoid the tray rubbing against the jaw or damage the soft tissue. If necessary, your dentist can place a temporary restoration while you’re waiting on your case to be completed. This is common practice for people who are missing a front tooth. That way, you won’t have a gap in your smile in the meantime. Are there risks associated with dental impressions? FIGURE 8-6 The initiator, aromatic sulfonate ester, dissociates and forms alkyl cations that bind the nitrogen atoms of the aziridine ring terminals of the prepolymer ( top, left). The arrows indicate binding between the cations (R +) with the nitrogen atoms. This action opens up the ring, and the reacted prepolymer ( center) now has two charged ethylene imine terminals ( NR CH 2 C +H 2), which can react with the nitrogen atoms of adjacent unreacted prepolymers, shown as the R 2-aziridine ring. This chain-propagation polymerization reaction yields a larger molecule ( right), which continues growing by binding with aziridine rings of additional unreacted prepolymers. The polymerization reaction terminates when the growing chain combines with a counterion. This cookie is set by the provider SnapEngage for the live chat functionality. This cookie is used for sending alias to chat agent and update the chat case. Peyton, J. H. 2002. Direct restoration of anterior teeth: review of clinical technique and case presentation. Pract. Proced. Aesthet. Dent. 14: 203– 210.Impression materials are introduced into the mouth as viscous pastes with precisely adjusted flow properties. The viscosity and flow behavior of the unmixed components are also important in regard to the ease of mixing, air entrapment during mixing, and the tendency for the trapped air to escape before the impression is made. Addition silicone impression material is generally used as a “final impression material” for the fabrication of crowns and bridges. Dental hygienists may (or may not) take this type of impression depending on their state practice act. From time to time, however, even those who do not take this type of impression may find themselves assisting with this procedure. An advantage of this material is that it does not need to be poured immediately after the impression is taken. Its stability and accuracy make it a very popular material. II.Procedure for the Double-Mix Putty-Wash Technique Polyvinyl ether siloxane (PVES) possesses ideal characteristics for making precise and accurate dental impressions. PVES dimensional stability owes to its better polymeric properties derived from its parent materials poly ethers and polyvinyl siloxanes. As recommended use of chemical disinfecting agents is getting more popular, there is a growing concern associated with the effect of disinfectants on PVES dimensional stability. This study was aimed to understand the PVES behavior when subjected to chemical disinfectants. Traditionally, creating an impression involves using dental putty to form a mould of the mouth; not only is this messy and potentially inaccurate; it may also be very uncomfortable and unpleasant for the patient, especially if they feel anxious or they have a very sensitive gag reflex. When a dentist creates a mould in this way, they insert the putty into the mouth and then shape it, so that it covers the teeth and gums; when the putty sets, a model of the mouth is formed. These models are then sent away to a laboratory where dental technicians will use them as a basis for a new restoration, such as a crown or bridge, or a gum shield for sport, for example.