Amount Of Tooth Structure Research Articles

ADVANCES IN DENTAL VENEERS: A REVIEW

Veneers have made a breakthrough in dentistry in recent times. They have been predicted to increase a patient's selfcondence, personal relationship, and even success in his or her career. Hence, with veneers, it is possible to create amazing esthetic results and yet retain a considerable amount of tooth structure. Successful results depend not only on the clinical and laboratory technique used for the assembly of veneers but also on an understanding of the scientic background behind its material aspect and case selection. Veneers have evolved in the past 10 years or so in the material aspect. Various materials are used to fabricate veneers like composite, processed composite, porcelain, ceramic, preformed acrylic laminates, and glass-ceramic veneers. The current article is a review that illustrates recent advancements in the material aspect of dental veneers.

Minimal invasive dentistry

The ideal definition of "Minimal Invasive (MI) Dentistry" is the use of a biological method rather than a typical (surgical) operational dentistry strategy to treat dental caries. When operational dentistry is necessary, it is now done in the most conservative way possible, with the least amount of tooth structure being harmed. This novel method of caries cares shifts the focus from detecting carious lesions as cavities (and a recurring cycle of restorations) to diagnosing the oral ecological imbalance and affecting biological changes in the biofilm. After stopping the disease process, MI aims to restore lost tooth structure and function, while optimizing the tooth's healing capacity. “Caries treatment has evolved from G.V. Black's extension for prevention to minimally intrusive owing to advancements in dental adhesives and restorative materials, increased knowledge of the caries process and remineralization, and changes in the incidence of caries. A decrease in cariogenic bacteria, new classifications of caries based on the location and size of lesion remineralization, and procedures and materials for minimally invasive cavity preparation are some of the topics covered in this book.”

Crown Lengthening surgery: An overview.

The term 'crown lengthening surgery' refers to a variety of techniques which aim to expose a greater amount of tooth structure around a tooth or group of teeth. The decision to treat and which technique to use will depend upon: the underlying aetiology; a thorough history and examination; results of any supporting investigations and a clear understanding of the intended outcome of treatment. This paper aims to provide an overview of crown lengthening surgery and is illustrated with clinical cases.

Comparative evaluation of fracture resistance of self-adapting PFS and elastic FRC post and core systems –An in vitrostudy

Background: Endodontically treated teeth (ETT) with extensive coronal destruction are more prone to fracture, so restoring these teeth with techniques that will not compromise the integrity of remaining tooth structure with the use of Post and core systems to retain full and final crown restorations seems mandatory. Anatomic posts have been introduced which have better adaptability to the canal anatomy and conserve more amount of tooth structure. Aim: This study was done to compare the fracture resistance of ETT restored with two anatomic post systems elastic FRC post (everStick) and self adapting PFS (Spirapost). Materials and Methods: Twenty single rooted maxillary central incisors were selected for the study. All the samples were endodontically treated and randomly divided into 2 groups (n=10) according to the post system used (PFS post – Group I, FRC– Group II). In all the samples, post space preparation was done and the posts were luted using dual cure resin cement (Para core, Coltene, Mumbai, India).The remaining core was built using composite resin (Filtek, 3M, ESPE, USA). The samples were stored in saline for one week. All the samples were thermocycled for 500 cycles from 5 to 55 0 c ±5 0 c with a dwelling time of 30 seconds in each bath and a transfer time of five seconds. Fracture resistance of the samples was measured using universal testing machine. The obtained data was statistically analyzed by using independent t test. Results: There was no statistically siginificant difference between fracture resistance values of FRC and PFS groups. 30% and 70% of the samples of PFS and FRC showed favourable fractures respectively. Conclusion: In this study it was concluded that fracture resistance of PFS was comparable to that of FRC post. However FRC group showed predominantly more number of favourable fractures.

Finite element stress analysis of restored primary teeth: A comparative evaluation between stainless steel crowns and preformed zirconia crowns

Background: Stainless steel crowns (SSCs) till now accepted as the best restorative modality for primary teeth, are being frowned on due to their poor esthetic appeal. The recently introduced preformed zirconia crowns are a more esthetic alternative, but the ability of these crowns to withstand stresses in the intraoral environment has not been tested. This study is a continuation of an earlier study done by the same authors to understand the stresses an SSC is subjected to under occlusal forces.Aims: The aim of this study is to compare the effectiveness of preformed zirconia crowns with the gold standard SSC for the restoration of primary teeth through a finite element analysis.Settings and Design: In vitro.Materials and Methods: The study design employed two finite element models, with the same amount of tooth structure, one restored with SSC and the other with preformed zirconia crown. The finite element models were exported to ANSYS software and subjected to an average simulated bite force of 245N.Statistical Analysis Used: The finite element models were exported to ANSYS software subjected to an average simulated bite force of 245N.Results: Preformed zirconia crowns suffered lesser Von maximal stresses along with its underlying dentine.Conclusions: Even at maximal physiologic masticatory force levels, a grossly destructed tooth restored with preformed zirconia crown can withstand stress better than a tooth restored with SSC.

Functional and esthetic rehabilitation of anterior primary teeth using two different approaches

Esthetic requirement of severely mutilated primary anterior teeth in the case of early childhood caries (ECC) has been a challenge to pediatric dentists. Numerous treatment approaches have been proposed to address the esthetics and retention of restorations in primary teeth. The choice of restoration depends on various factors such as amount of tooth structure remaining, ability to obtain adequate moisture control, child's cooperating ability, esthetic demands, and cost factor. This case report documents comparison of two esthetic techniques for the management of primary anterior teeth.

Restoration of endodontically treated teeth: criteria and technique considerations.

The restoration of endodontically treated teeth is often required and may represent a challenge as there is no consensus on ideal treatment. The failure of endodontically treated teeth is usually not a consequence of endodontic treatment, but inadequate restorative therapy or periodontal reasons. Prior to the initiation of endodontic treatment the restorability, occlusal function, periodontal health, biologic width, and crown-to-root ratio need to be assessed. If acceptable, the appropriate technique, material, and type of restoration to restore function need to be considered. Posts are used to provide retention for the core material and to replace missing tooth structure. The residual amount of tooth structure will determine its stability for restoration. The creation of adequate ferrule (approaching 2 mm circumferentially is ideal) minimizes the damaging effects of lateral and rotational forces on the restoration and post.

Ceramic onlay for endodontically treated mandibular molar

Restoration of endodontically treated teeth is important for the success of endodontic treatment. In full coverage restorations, maximum amount of tooth structure is compromised, so as to conserve the amount of tooth structure partial coverage restorations, can be preferred. This case report is on fabrication of a conservative tooth colored restoration for an endodontically treated posterior tooth. A 22-year-old male patient presented with pain in the mandibular left first molar. After endodontic treatment, composite material was used as postendodontic restoration. The tooth was then prepared to receive a ceramic onlay and bonded with self-adhesive universal resin cement. Ceramic onlay restoration was periodically examined up to 2 years.

Evaluation and comparison of the effect of enamel preparation designs on fracture resistance of micro-filled and nano-filled composite resin: Anin vitrostudy

Background and Objectives: The main objective of this study was to compare and evaluate the effect of enamel preparation designs; bevel and stair step chamfer, on fracture resistance of composite resins (micro-filled and nano-filled) using incremental technique. Materials and Methods: The sample group consisted of 60 non-carious maxillary permanent central incisors. They were divided into four groups of 15 teeth each. According to the group, the teeth were prepared and restored with corresponding design and material. The teeth were subjected to compression bending test under instron testing machine then were examined under stereomicroscope. The results were subjected to statistical analysis. Results: Mean peak failure load (Newton) of among experimental groups was observed in the order; Group I (Bevel with micro-filled material) was 255.6 ± 65.0 N and Group II (bevel with nano-filled material) l was 282.1 ± 67.7 N. Group III (Stair-step chamfer with micro-filled material) was 249.8 ± 78.0 N. and Group IV (Stair-step chamfer with nano-filled material) was 283.3 ± 52.0 N. Results of the analysis of variance revealed there was no significant difference in the mean peak failure load values of the four different groups. Failure mode evaluation revealed, majority of the failures occurred as cohesive and mixed type for all the experimental groups. Adhesive type failure was observed maximum (47%) in the bevel group. Stair-step chamfer preparation showed the greatest potential for application, but also involved sacrificing less amount of tooth structure adjacent to fractured edge. Conclusion: This study concludes that both the preparations, bevel as well as stair-step chamfer are equally good to resist fracture when restored either with micro-filled or nano-filled composite resins.

COMMENTARY. Clinical Decisions for Anterior Restorations: The Concept of Restorative Volume1

Minimally invasive treatment has become a mantra for all health care providers. It has often been said that “dentistrybegets dentistry.”The more dentistry you perform for an individual, the more dentistry that person will be likely toneed in the future.We know there is no such thing as a “permanent restoration.”With future treatment a possibilityfor many restored teeth, it becomes apparent that the more tooth structure that can preserved, the more that will beavailable later.Years ago, the only type of indirect restoration that could adequately restore significant amounts of diseased toothstructure was gold.The demand for more esthetic restorations led to the development of acrylic to gold and porcelainfused to metal restorations.These required removal of more tooth structure to allow for thickness of both metal- andtooth-colored material.The advent of all-ceramic crowns often necessitated even more removal of tooth structure foradequate strength. More involved and demanding adhesive techniques were required.The combination of moreintrusive preparation and technique-sensitive bonding procedures resulted in an increased need for endodonticroot-canal therapy.The public has become aware of these problems and is demanding more conservative treatment. Itis not surprising that controversies abound today about prepared versus non-prepared porcelain laminate veneers.In today’s economic environment patients are seeking more economical solutions to their problems.They arechallenged to afford extensive indirect procedures and are opting for simpler, less expensive direct restorations.Thenumber of indirect procedures has reportedly decreased in North America the past 3 years. During this same periodof time, several new all-ceramics restorations with increased strength have become popular. Lithium disilicaterestorations and zirconia-based crowns have increased.These restorations do not require bonding but can becemented.The all-zirconia crowns do not require as much removal of tooth structure.This paper is one of the first to logically address the treatment decision-making process for specific treatments withregards to the amount of tooth structure that will have to be removed.

Full-mouth minimally invasive adhesive rehabilitation to treat severe dental erosion: a case report.

Dental erosion is increasing, and only recently are clinicians starting to acknowledge the problem. A prospective clinical trial investigating which therapeutic approach must be undertaken to treat erosion and when is under way at the University of Geneva (Geneva Erosion Study). All patients affected by dental erosion who present with signs of dentin exposure are immediately treated using only adhesive techniques. In this article, the full-mouth adhesive rehabilitation of one of these patients affected by severe dental erosion (ACE class IV) is illustrated. By the end of the therapy, a very pleasing esthetic outcome had been achieved (esthetic success), all of the patient's teeth maintained their vitality, and the amount of tooth structure sacrificed to complete the adhesive full-mouth rehabilitation was negligible (biological success).

The Influence of Post in Endodontically Treated Molar Abutment on Fixed Dentures Success Rate

Many dentists believe that the tooth need reinforcement provided by post before the definite restoration is placed. However, others suggest not to use post when posterior teeth especially molars, still have significant amount of tooth structure. Therefore, when endodontically treated molar is considered to be used as fixed denture abut-ment, clinicians must have proper knowledge about the impact of post placement. This literature will describe considerations regarding post placement in endodontically treated molar abutment in fixed partial dentures and their influence to the success rate. Previous studies implied the need of proper measurement of the amount of remaining tooth structure, the type of intracoronal reinforcement of the abutment, and the functional loads to ensure the success of fixed denture treatment. When planning definitive restorations for endodontically treated abutment teeth, some even suggest to use post and core to fulfill the need of reinforcement. On the contrary, others find that when a post is use in endodontically treated abutment teeth, the failure of custom made-tapered cast post and core is relatively high, whereas the use of amalgam or composite core in posterior teeth especially molars with adequate amount of tooth structure is sufficient due to post system’s limited influence on the suc-cess rate. Based on literature review, for cases with adequate tooth stucture, it can be concluded that the influ-ence of post placement in endodontically treated molar abutment to fixed partial dentures success rate is very limited. DOI: 10.14693/jdi.v18i2.64

Mechanical retention versus bonding of amalgam and gallium alloy restorations

The retention of amalgam and gallium alloy restorations in proximal box forms was measured in vitro, and three different adhesives to conventional undercuts were compared. For control, restorations were placed without undercuts or adhesives. No significant difference was found between amalgam and gallium alloys with each of the five methods of retention used. Alloys placed without retention or adhesives were significantly less retentive than all other groups. When Tytin alloy was used, no difference was found in retention among the restorations retained with Panavia or All-Bond adhesive or an occlusal dovetail and retention grooves, but Amalgambond adhesive was less retentive than all three of these methods. When gallium alloy was used, both Panavia and All-Bond adhesive were more retentive than undercuts, but the effect of Amalgambond adhesive was comparable to that of undercuts. The results of this study indicate that adhesives could be used ia place of traditional undercuts to retain amalgam and gallium alloys, thus saving a considerable amount of tooth structure.

Enhancement of Argon Laser Effect on Dissolution and Loss of Human Enamel

ABSTRACT Previous studies have recorded the reduction of caries-like lesions in extracted human teeth that have been irradiated with CO2 laser. Other studies have shown a decrease in dissolution of enamel that has been irradiated with Argon laser. This study was conducted to see if there are additive effects between argon laser irradiation and those of chemical inhibitors, ethane-l-hydroxy-l,l-diphosphonic acid (EHDP) and dodecylamine HC1 (DAC) on the loss of tooth structure due to demineralization of dental enamel. The amount of demineralization was determined in a rotating disk assembly (0.1 M acetate buffer, pH 4.5) for 24 hr and the results determined and plotted against the nonlased control using microradiography and computerized imaging. The amount of tooth structure lost to demineralization in 4.5 pH acid bath in a 24-hr period was reduced from approximately 140 μm to nearly zero when Argon lased enamel was exposed to DAC or EHDP.

ALTERNATIVE CROWN SYSTEMS: Is the Metal-Ceramic Crown Always the Restoration of Choice?

ALTERNATIVE CROWN SYSTEMS: Is the Metal-Ceramic Crown Always the Restoration of Choice?

Clinically significant factors in dowel design

When a method of intracoronal reinforcement is selected, many factors must be weighed. The hazards include (1) the induced stresses and the risk of fracture during placement of the dowel, (2) the probability of root perforation during post space preparation, (3) the wedging action of tapered dowels, and (4) the incidence of fracture with self-threading pins in devitalized teeth. The amount of tooth structure that remains after endodontic therapy and post space preparation is paramount. Endodontic and restorative treatment must be aimed at preserving tooth structure to provide strength and resistance to fracture of the pulpless tooth. To fabricate a large-diameter dowel with a strength that greatly exceeds that of the endodontically treated root decreases the prognosis for clinical success.