Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Tooth Preparation”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 937 records · Page 52Linked to original sources
PubMed2005

Bond angle effects on microtensile bonds: laboratory and FEA comparison.

OBJECTIVE: To test the hypothesis that there is a reduction in bond strength when a microtensile load is applied to adhesive junctions prepared at 10, 20 and 30 degrees to the usual perpendicular interface. To evaluate the effect of bond angle and adhesive layer thickness on stress levels within the adhesive joint utilizing FEA. METHODS: Twenty-four non-carious third molars were selected, occlusal enamel removed and polished perpendicular to the long axis of the tooth. The Clearfil SE Bond and Single Bond were applied on the dentin. A 4 mm resin restoration, Z 100, was built up. The teeth were sectioned at 10 degrees, 20 degrees and 30 degrees to the bonding interface (n = 3). The control (n = 3) group had all cuts parallel to the tooth longitudinal axis (0 degrees bond angle). The bond values were calculated in MPa and Two-Way ANOVA and Tukey test applied. FEA was performed (1 mm/side square specimens) to obtain the maximum principal stress (MPS) in the microtensile-model for each bond angle and for varying adhesive thickness from 20 microm to 200 microm for each group. RESULTS: The bond strength results diminish as the angle on the interface increased (P<0.05) for Clearfil SE Bond between 0 (control) and 30 degrees, and for Single Bond between 0 (control) and 10, 20, and 30 degrees. The hypothesis can be fully accepted for Single Bond and partially accepted for Clearfil SE Bond. For the FEA, there was a trend toward decreasing MPS as the bond angle increased, while the MPS for each angled group increased with adhesive layer thickness. SIGNIFICANCE: The MPS results for angled interfaces, exhibited the same trend as the lab values. FEA results indicated an MPS increase with increased adhesive thickness.

Bisphenol A-Glycidyl Methacrylate↗
PubMedDate not supplied

Vertical shoulder preparation design for porcelain laminate veneer restorations.

The clinical success of porcelain laminate veneers depends on numerous factors that include the framework of the dental and gingival structures and their ability to withstand masticatory forces. In order to ensure aesthetic harmony, the clinician must reproduce numerous anatomical components (e.g., cementoenamel junction, points of concavity, developmental lobes, line angles, incisal edge survey form) in restorations while simultaneously providing sufficient functional integrity. This article demonstrates the vertical shoulder preparation design, which enhances the aesthetics and stabilization factors of porcelain laminate veneer restorations.

Adult↗
PubMed2006

The effect of preparation height and taper on cement lute stress: a three-dimensional finite element analysis.

Three dimensional finite element models of an upper second premolar and molar with full veneer gold crown preparations were developed from extracted samples. The cement lute width was kept constant at 40 microm, but the height and preparation taper were varied. For both models the preparation height was either 1.5 mm (short preparation) or 3 mm (long preparation). The preparation taper was either 10 degree or 30 degree, giving a total of eight models. Each model was loaded with a 10 N horizontal load, a 10 N vertical load or a 10 N load distributed across the occlusal surface. The maximum shear stress and the maximum Von Mises' stress in the cement lute of each model were recorded. For the premolar, the maximum shear stresses ranged from 0.3-5.43 MPa and the maximum Von Mises' stress ranged from 1.44-14.98 MPa. For the molar, the maximum shear stresses ranged from 0.15-5.22 MPa and the maximum Von Mises' stress ranged from 0.3 7-15.02 MPa. The stress fields were consistently higher in the premolar with a 30 degree preparation taper compared to the 10 degree taper. The attainment of a cavity taper of 100 is still important to minimise stress in the cement lute and is particularly important in teeth with a lower preparation surface area such as a premolar

Bicuspid↗
PubMed1995

Anterior maxillary aesthetics utilizing all-ceramic restorations.

The use of all-ceramic systems has increased significantly during recent years, due to the improved strength and the introduction of a new generation of dental adhesive agents and resin cements. Both factors permit reliable and predictable results in single jacket crown restorations in the maxillary anterior region. Due to their natural appearance, the all-ceramic materials, especially the glass ceramics, blend harmoniously with the oral environment and are particularly appreciated where aesthetics is a priority. The learning objective of this article is to demonstrate a routine utilization of all-ceramic systems in the maxillary anterior region, preceded by a proper case selection. Two clinical cases are used to illustrate the preparation procedure, the importance of well-integrated provisional restorations, and the accuracy in transferring provisional information onto the final jacket crowns.

Adult↗
PubMed1996

An investigation into the measurement of the working length of immature incisor teeth requiring endodontic treatment in children.

A study was undertaken to determine if a tactile technique, using absorbent paper points, could be used to estimate the working length of nonvital immature incisor teeth undergoing endodontic treatment. Two operators were involved in measuring 35 incisor teeth. The tactile technique was found to be valid and reliable. In 95% of the cases the estimated working length was within 1 mm of the radiographic diagnostic length. It is recommended that diagnostic radiographs are no longer necessary in the majority of cases involving endodontic treatment of incisor teeth requiring root end closure in children, for practitioners who are regularly carrying out endodontic treatment of immature incisor teeth. However, if a tooth has been on open drainage a diagnostic radiograph is still required.

Adolescent↗
PubMed2004

Effect of bur type on microtensile bond strengths of self-etching systems to human dentin.

PURPOSE: To compare the microtensile bond strength (microTBS) of five adhesives to human dentin prepared with 600-grit SiC abrasive paper (SiC), a diamond rotary instrument, or a carbide bur. The null hypothesis was that different cavity preparation instruments do not affect adhesion of resin adhesives. MATERIALS AND METHODS: Human molars (n = 45) were randomly divided into three groups according to surface treatment. Each group was bonded using a total-etch adhesive (Single Bond, 3M ESPE), one of three self-etching primer systems (Clearfil SE Bond or ABF, Kuraray; Imperva Fluorobond, Shofu), or a self-etching adhesive (One-Up Bond F, Tokuyama). A 4-mm composite crown was built over the bonded surface. Specimens were stored in water for 24 h at 37 degrees C. They were sectioned into 0.7-mm-thick slabs, trimmed to a cross-sectional area of 1 mm2, and loaded to failure at a crosshead speed of 1 mm/min using a tabletop tester (EZ-Test, Shimadzu). Microtensile bond strength data were analyzed using analysis of variance and Fisher's PLSD test. RESULTS: Surface preparation using a carbide bur generally yielded higher bond strengths than preparation using either a diamond rotary instrument or SiC abrasive paper. SE Bond had the highest mean microTBS of the five adhesives tested. CONCLUSION: Resin-dentin bond strengths can be affected by the type of instrument used to prepare the tooth. Specifically, higher bond strengths might be achieved by using carbide burs rather than diamond cutting instruments.

Acid Etching, Dental↗
PubMed2000

Fracture strength of In-Ceram all-ceramic bridges in relation to cervical shape and try-in procedure. An in-vitro study.

Investigations were performed on the strength of dental porcelain depending on whether it was exposed to saliva before or after the final firing. Forty porcelain specimens were fabricated and subjected to different treatments. A three-point flexural test was performed. In a second study investigations were performed to compare how the cervical shape of the preparation influenced the fracture strength of fixed partial dentures made of glass-infiltrated aluminium oxide. It was concluded that short-term exposure to saliva could have a negative effect on the strength of porcelain and that all-ceramic bridges luted with non-adhesive luting techniques should be supported by abutments with shoulder preparations.

Aluminum Oxide↗
PubMed2000

Clinical evaluation of a new resin composite crown system to eliminate postoperative sensitivity.

This study evaluated the long-term clinical performance of a new resin composite restorative system with a 4-META dentin-bonding agent to seal complete crown preparations prior to temporization and after permanent luting with a companion resin cement. Complete-coverage crown preparations were completed on 33 vital teeth and 5 nonvital teeth (control). The new restorative material demonstrated satisfactory clinical performance for the 3-year test period. The dentin-bonding agent and its companion resin cement successfully eliminated postoperative hypersensitivity in 100% of the prepared vital teeth over the 3-year term, suggesting excellent seal of dentinal tubules exposed by the complete-crown preparations.

Acrylic Resins↗
PubMed2003

Contemporary perspectives on post-core systems.

The challenge of restoring endodontically-treated teeth has spawned a considerable diversity in foundation restorations and a plethora of publications in the dental literature. Moreover, it seems that an inverse relationship has developed between the escalating complexity in selecting a post-core system and the volume of reliable scientific data upon which clinicians base their treatment decisions. In the quest to restore aesthetics, function, and reduce the risk of treatment failure there is now a much greater emphasis on the preservation of sound tooth structure, tooth isolation for intracanal procedures, sealing the root canal and adapting the advantages and limitations of dental materials to the presenting clinical situation. The relatively recent introduction of metal-free posts into mainstream prosthodontics has added an aesthetic dimension to treatment planning. New adhesive systems and resin-based luting agents have the potential to create a genuine adhesive continuum between the tooth and post-core complex. While these developments may have significant ramifications with respect to treatment prognosis, the long-term clinical performance of contemporary post-core systems is unclear.

Dental Materials↗
PubMed2005

Qualitative computer aided evaluation of dental impressions in vivo.

OBJECTIVES: Clinical investigations dealing with the precision of different impression techniques are rare. Objective of the present study was to develop and evaluate a procedure for the qualitative analysis of the three-dimensional impression precision based on an established in-vitro procedure. The zero hypothesis to be tested was that the precision of impressions does not differ depending on the impression technique used (single-step, monophase and two-step-techniques) and on clinical variables. METHODS: Digital surface data of patient's teeth prepared for crowns were gathered from standardized manufactured master casts after impressions with three different techniques were taken in a randomized order. Data-sets were analyzed for each patient in comparison with the one-step impression chosen as the reference. The qualitative analysis was limited to data-points within the 99.5%-range. Based on the color-coded representation areas with maximum deviations were determined (preparation margin and the mantle and occlusal surface). To qualitatively analyze the precision of the impression techniques, the hypothesis was tested in linear models for repeated measures factors (p < 0.05). RESULTS: For the positive 99.5% deviations no variables with significant influence were determined in the statistical analysis. In contrast, the impression technique and the position of the preparation margin significantly influenced the negative 99.5% deviations. SIGNIFICANCE: The influence of clinical parameter on the deviations between impression techniques can be determined reliably using the 99.5 percentile of the deviations. An analysis regarding the areas with maximum deviations showed high clinical relevance. The preparation margin was pointed out as the weak spot of impression taking.

Computer-Aided Design↗
PubMed2002

Crowns and other extra-coronal restorations: preparations for full veneer crowns.

Preparations for full veneer crowns is the eighth in the series on crowns and other extra-coronal restorations. Whilst handpiece skills are important, many other factors combine to ensure provision of a satisfactory full veneer crown (also termed 'full coverage crown'). Our aim in writing this article is to consider the principles which influence crown preparation, seasoned with clinical advice our undergraduate and postgraduate students have found useful.

Composite Resins↗
PubMed2001

[Impressions in conservative dentistry].

In conservative dentistry, indirect restorations are rather seldom choosen because direct restorations give relatively good results and fit well to conditions of social dentistry. If an indirect restoration is to be realised, it has to be decided if it will be an inlay, an onlay or a crown and which material will be used. A one step putty wash technique impression is the best for registering inlay-onlay preparations. Most often, preparations are few and grouped and allow the dual arch technique. By this technique, it is possible to register in one time the preparations, the antagonists and their occlusal relation. A complete description of this technique is given in a case report.

Bruxism↗
PubMed2002

Fluoride-releasing resin bonding of amalgam restorations in primary teeth: in vitro secondary caries effect.

PURPOSE: To evaluate the effects of a fluoride-releasing resin designed for amalgam bonding on secondary caries formation in primary teeth restored with amalgams. MATERIALS AND METHODS: Primary teeth with caries-free buccal and lingual surfaces were selected and underwent a fluoride-free prophylaxis. Cavity preparations were performed in the buccal and lingual smooth surfaces of 20 primary teeth. A fluoride-releasing dimethacrylate resin bonding agent (Alloybond) was placed prior to amalgam restoration (Dispersalloy) of the cavity preparations in 10 teeth. Amalgam restorations placed in 10 teeth following copal cavity varnish (Copalite) served as controls. The teeth were thermocycled in synthetic saliva (500 cycles, 5 degrees-50 degrees C), and then coated with an acid-resistant coating, leaving a 1mm rim of sound enamel surrounding the restorations. Artificial secondary caries were created (2.2 mM calcium, 2.2 mM phosphate, 50 mM acetic acid, 0.5 ppm fluoride, pH 3.90). Following lesion formation, longitudinal sections (five per tooth) were prepared for polarized light evaluation. Mean depths for the primary surface lesions were determined using a computer-interfaced digitized tablet. Cavity wall lesion frequencies were also evaluated. Comparisons were made between groups (ANOVA, DMR). RESULTS: Primary surface lesion depth was reduced significantly (P < 0.05) with Alloybond-amalgams (135 +/- 14 microm) when compared with Copalite-amalgams (184 +/- 21 microm). Cavity wall lesion frequency was decreased (P < 0.05) significantly with Alloybond-amalgams (57%) compared with Copalite-amalgams (89%). The beneficial effect of the fluoride-releasing amalgam bonding agent was not limited to the cavosurface enamel. The caries susceptibility of enamel surfaces adjacent to amalgams with the fluoride-releasing bonding agent was decreased considerably. The incorporation of the amalgam-bonding resin with fluoride-releasing capabilities provided greater protection against a constant cariogenic attack over that for a conventional amalgam restoration.

Analysis of Variance↗
PubMed1997

Full veneer versus traditional veneer preparation: a discussion of interproximal extension.

STATEMENT OF PROBLEM: Traditional veneer preparation has come to represent an almost universally accepted guideline of veneer preparation. It calls for an interproximal finish line at or just into the contact point. However, in certain situations, such an approach can have functional and esthetic limitations. PURPOSE: This article reviews those functional and esthetic limitations and discusses an alternative technique, the full veneer preparation. The advantages and disadvantages of this approach are discussed in relation to veneer cases with malaligned teeth, diastema, discoloration, black spaces, restorations, and/or veneers next to crowns.

Crowns↗
PubMed1999

Procera all-ceramic crowns: a new approach to an old problem?

Increasing patient expectations regarding the appearance of restorations continue to test the ingenuity and skill of the dental team. To this end the quest for sufficiently strong, metal-free, all-ceramic restorations to function in all areas of the mouth continues apace. We report on a possible solution to this problem that uses computer-aided design/computer-aided milling (CAD/CAM) technology coupled with a novel, densely sintered, ceramic material. In this article we offer suggestions for case selection, preparation design, and luting procedures, and in addition illustrate these with a number of completed cases.

Adult↗
PubMedDate not supplied

Placement protocol for an anterior fiber-reinforced composite restoration.

The new classification of metal-free restorative materials provides the clinician with a durable, flexible, and aesthetic laboratory-fabricated alternative to conventional porcelain-fused-to-metal (PFM) full-coverage crowns, inlay and onlay restorations, and single pontic bridges. With exceptional physical and optical characteristics, restorations fabricated utilizing the new ceramic optimized polymer (Ceromer) (Targis, Ivoclar Williams, Amherst, NY) and fiber-reinforced composite (FRC) framework (Vectris, Ivoclar Williams, Amherst, NY) materials can also be utilized predictably in the anterior segment. The success of metal-free restorations can be achieved by following conventional prosthodontic principles for preparation, cementation, and finishing. This article demonstrates the appropriate treatment protocol in order to achieve aesthetically acceptable and durable anterior results utilizing a metal-free restorative system for "Maryland-like" bridge restorations.

Adult↗