Field Of Prosthodontics Research Articles

Application of lasers in prosthodontics: A review

LASERS has a wide range of action, and it is application in the field of prosthodontics have replaced scalpel to reasonable extend all over the surgical field and other conventional methods. An upcoming new technology replaces several shortcomings but by having its own risks and limitations. The aim of this article is to elaborate the application and uses of lasers in prosthodontics and the revolution by lasers in providing precise procedures to the patient.

Additive Manufacturing Techniques in Prosthodontics: Where Do We Currently Stand? A Critical Review.

The aim of this article was to critically review the current application of additive manufacturing (AM)/3D-printing techniques in prosthodontics and to highlight the influence of various technical factors involved in different AM technologies. A standard approach of searching MEDLINE, EMBASE, and Google Scholar databases was followed. The following search terms were used: (Prosth* OR Restoration) AND (Prototype OR Additive Manufacture* OR Compute* OR 3D-print* OR CAD/CAM) AND (Dentistry OR Dental). Hand searching the reference lists of the included articles and personal connections revealed additional relevant articles. Selection criteria were any article written in English and reporting on the application of AM in prosthodontics from 1990 to February 2016. From a total of 4,290 articles identified, 33 were seen as relevant. Of these, 3 were narrative reviews, 18 were in vitro studies, and 12 were clinical in vivo studies. Different AM technologies are applied in prosthodontics, directly and indirectly for the fabrication of fixed metal copings, metal frameworks for removable partial dentures, and plastic mock-ups and resin patterns for further conventional metal castings. Technical factors involved in different AM techniques influence the overall quality, the mechanical properties of the printed parts, and the total cost and manufacturing time. AM is promising and offers new possibilities in the field of prosthodontics, though its application is still limited. An understanding of these limitations and of developments in material science is crucial prior to considering AM as an acceptable method for the fabrication of dental prostheses.

Application and outlook of three-dimensional printing in prosthetic dentistry

At present, three-dimensional (3D) printing has been applied in many aspects in the field of prosthodontics, such as dental models, wax patterns, guide plates, dental restoration and customized implants. The common forming principles include light curing, sintering and melting-condensation, the materials include pure wax, resin, metal and ceramics. However, the printing precision and the strength of multi-material integrated forming, remains to be improved. In addition, as a technology by which the internal structure of a material can be customized manufacturing, further advantage of 3D printing used in the manufacture of dental restoration lies in the customization functional bionic micro-structures, but the related research is still in its infancy. The review briefly summarizes the commonly used 3D printing crafts in prosthetic dentistry, and details clinical applications and evaluations, provides references for clinical decision and further research.

Prosthetic Rehabilitation in a Partially Edentulous Patient with Magnetic Dentures

Since their introduction in the field of dentistry, magnets have been gaining popularity. In the field of prosthodontics, they can be used to enhance the retention of the denture in a completely edentulous patient as well as in partially edentulous patient in form of magnetically retained overdenture. This article demonstates the rehabilitation of a partially edentulous patient with a magnetic assembly mandibular overdenture and conventional maxillary complete denture.

Low-temperature Degradation of Zirconia-based All-ceramic Crowns Materials: A Mini Review and Outlook

Zirconia-based bioceramics have been widely applied in the field of prosthodontics owing to its desirable mechanical performance, biocompatibility and aesthetics. However, the low-temperature degradation (LTD) of tetragonal zirconia (ZrO2) under intraoral condition can lead to the deterioration of mechanical properties of ZrO2 dental crowns, which contribute to many clinical failures in long-term observations. The long-term tetragonal phase stability and mechanical properties of yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) are influenced by grain size of ZrO2 crystals, distribution and properties of stabilizers, the humid environment, etc. However, it is still difficult to control the abovementioned factors at the same time. This review summarizes the major advances in researches dealing with LTD and clarifies the obstacles to stabilization of the tetragonal ZrO2. Furthermore, the suggestions on improving the LTD resistance of tetragonal ZrO2 are proposed, which is the catalyst to promote the long-term stability of ZrO2-based all-ceramic crowns.

Development and prospect of digital technology in the field of prosthodontics

The development of digital technology is gradually changing clinical practice and laboratory procedure of prosthodontics. After decades of exploration and development, the modern digital technology has been perfectly merged with prosthodontics and created a brand new treatment mode. The application of digital impression, digital design and digital processing has changed the way we treat patients and the way we communicate with patients. The data storage also provides a basis for long-term follow-up. The establishment of digital remote system, transferring data through internet, has improved communication in dental technique, tracing analysis of patient's condition, sharing and management of medical data, and popularization and promotion of knowledge. Digital technology promoted the development of prosthodontics in the direction of more precision, more convenience, more efficiency and more simulation in functional recovery, which will be one of the development directions of dentistry and even the medical science in the future.

Infection Control in Prosthodontics

The dentists and allied health workers are exposed to wide variety of potentially dangerous micro-organisms. This occupational potential for disease transmission becomes evident as most human microbial pathogens have been isolated from oral secretions. Because of repeated exposure to the microorganisms present in blood and saliva, the incidence of certain infectious diseases has been significantly higher among dental professionals.HIV, Hepatitis B, Tuberculosis and Herpes simplex virus infections are well recognized and indicate the need for increased understanding of modes of disease transmission and infection control procedures. Dental prostheses, impressions, models and items used in their fabrication are potential sources for cross infectio n and should be handled in a manner that prevents exposure of dental health care professionals and patients to infectious agents. This article highlights various methods of infection control particularly in the field of Prosthodontics to prevent the transmi ssion of diseases between patients, dentists and lab personnel. Routinely dental care professionals are at an increased risk of cross infection while treating patients. This occupational potential for disease transmission becomes evident initially when one realizes that most human microbial pathogens have been isolated from oral secretions. Because of repeated exposure to the microorganisms present in blood and saliva, the incidence of certain infectious diseases has been significantly higher among dental professionals than observed for the general population. Hepatitis B, HIV, Tuberculosis and Herpes Simplex Virus infections are well recognized and indicate the need for increased understanding of modes of disease transmission and infection control procedures by dental care providers. (1)

Publication of statistically significant research findings in prosthodontics & implant dentistry in the context of other dental specialties

ObjectivesTo assess the hypothesis that there is excessive reporting of statistically significant studies published in prosthodontic and implantology journals, which could indicate selective publication. MethodsThe last 30 issues of 9 journals in prosthodontics and implant dentistry were hand-searched for articles with statistical analyses. The percentages of significant and non-significant results were tabulated by parameter of interest. Univariable/multivariable logistic regression analyses were applied to identify possible predictors of reporting statistically significance findings. The results of this study were compared with similar studies in dentistry with random-effects meta-analyses. ResultsFrom the 2323 included studies 71% of them reported statistically significant results, with the significant results ranging from 47% to 86%. Multivariable modeling identified that geographical area and involvement of statistician were predictors of statistically significant results. Compared to interventional studies, the odds that in vitro and observational studies would report statistically significant results was increased by 1.20 times (OR: 2.20, 95% CI: 1.66–2.92) and 0.35 times (OR: 1.35, 95% CI: 1.05–1.73), respectively. The probability of statistically significant results from randomized controlled trials was significantly lower compared to various study designs (difference: 30%, 95% CI: 11–49%). Likewise the probability of statistically significant results in prosthodontics and implant dentistry was lower compared to other dental specialties, but this result did not reach statistical significant (P>0.05). ConclusionsThe majority of studies identified in the fields of prosthodontics and implant dentistry presented statistically significant results. The same trend existed in publications of other specialties in dentistry.

Intraoral Digital Impression Technique: A Review.

With the techniques of computer-aided design and computer-aided manufacturing (CAD/CAM) being applied in the field of prosthodontics, a concept of intraoral digital impressions was put forward in the early 1980s. It has drawn comprehensive attention from dentists and has been used for dental prosthesis fabrication in a number of cases. This new digital impression technique is expected to bring about absolute digitization to the mode of prosthodontics. A few published articles have indicated that dental prostheses fabricated from intraoral digital impressions have exhibited remarkable advantages over those from conventional impressions in several respects. The present review discusses intraoral digital impression techniques in terms of the following aspects: (1) categories and principles of intraoral digital impression devices currently available; (2) operating characteristics of the devices; and (3) comparison of the manipulation, accuracy, and repeatability between intraoral digital impression and conventional impression.

Pre-Definitive Prosthodontic Treatment with Rehabilitation Devices

AbstractIn prosthodontic treatment plan, decisions must be made regarding oral tissue rehabilitation and other necessary pre-prosthetic measures. The rehabilitation prostheses are very useful devices in the field of prosthodontics. It is essential that the mouth should be in an optimal state of health prior to commencing prosthetic treatment and failure to achieve this may produce an unsatisfactory treatment result. Depending on a variety of situations, the dentist may find it necessary to modify the patient's existing dentures or, occasionally, to construct a special appliance. This article deals with several preliminary (non-definitive) treatment options available along with a brief account of their rationale.

Revolutionizing restorative dentistry: an overview.

The field of science and research is ever changing and the scientific discipline of prosthodontics is no exception. The practice of prosthodontics and the supporting technology involved has evolved tremendously from the traditional to the contemporary. As a result of continual developments in technology, new methods of production and new treatment concepts may be expected. Clinicians must have certain basic knowledge if they are to benefit from these new procedures. This article reviews the contemporary trends in the field of prosthodontics and provides an insight into what one might expect in the near future.

An in vitro study of the effect of design of repair surface on the transverse strength of repaired acrylic resin using autopolymerizing resin

The fracture of complete denture is a common occurrence in the field of prosthodontics. Often if all other criteria are met such as good aesthetics, occlusion, and functionality; denture repair is acceptable. Once denture fractures, we would want the joint surface strength to be as good as original. The purpose of this study was to determine the effect of different repair surface design on the transverse strength of repaired acrylic denture resin. Sixty specimens of heat-cured acrylic resin of dimension 65 mm × 20 mm × 2.5 mm were prepared using a special die. Transverse strength of 15 samples was calculated which serves as a control group. Three different types of joint surface contours were prepared each having 15 samples each as butt, round, and rabbet joint. Transverse strength of three joint contours was then compared with control group and also they were compared with each other and result was statistically analyzed with one-way analysis of variance (ANOVA) and Post-hoc ANOVA Tukey's HSD test at 5% level of significance. Z-test of proportion was also done for types of failures. Transverse strength of original specimen was higher than that of repaired specimens. Transverse strength of round joint was higher than the butt and rabbet joint. Methods of repair have significant effect on strength of repaired denture. Round joint design of repair technique was far superior.

Comparative analysis on measuring performances of dental intraoral and extraoral optical 3D digitization systems

Implementation of the methods of 3D digitization in dental practice is a modern and sophisticated alternative to the method of conventional impressions. Among many different methods of 3D digitization applied in dentistry, optical methods can be considered as today mostly applied, especially in the field of prosthodontics. The developments of this kind of systems have converged in two main directions – extraoral and intraoral systems. The main quality parameters for evaluating measuring performances of 3D digitization methods and systems include accuracy and precision. By introducing LED blue light in intra- and extraoral cameras, the Cerec system has significantly improved the quality of 3D digitization results. As the technical features of cameras in both types of systems are identical and the difference of the digitization methods is connected only to operating environments, the main goal of the research was to analyze whether different digitization conditions significantly influence the systems’ measuring performances. Analyzes were focused on investigating accuracy and precision of two mentioned specialized dental optical systems on the basis of CAD inspection, with special attention on evaluating statistically significant differences within the obtained results. Statistically significant difference was not found in systems’ precision, while the extra oral system was found as of significantly higher accuracy.

Mandibular Overdenture Retained by Magnetic Assembly: A Clinical tip.

The preservation of remaining root structure and alveolar bone covering them with denture has been used since many years. Tooth-retained overdentures transfer occlusal forces to the alveolar bone through the periodontal ligament of the retained tooth roots and thereby prevent bone resorption. Applications of magnets in overdenture technique has been widely used in dentistry in the field of prosthodontics, as they can be manufactured in small dimensions as retentive devices for complete denture, removable partial dentures, obturators and maxillofacial prosthesis. This article presents a simple and efficient method of fabrication of mandibular over denture retained by magnets in a patient whose mandibular residual ridge is severely resorbed with few remaining teeth and maxillary conventional removable partial denture. Mandibular over denture retained by magnets assembly consist of magnet and coping with keeper on remaining tooth structure to rehabilitate the patient since magnetic attachments can provide support, stability and retention.

Diagnosis and Management of Occlusal Wear: A Case Report

The rationale for doing full mouth rehabilitation are, when occlusal forces become traumatic hampering the health of periodontal tissues, extensive occlusal diseases, trauma, temporomandibular joint disease and congenital disorders with malformed dentition. Literature exposes that full mouth fixed rehabilitation is one of the taxing procedures in the field of Prosthodontics. A critical aspect for successful occlusal rehabilitation is to determine the aetiology, correct sequence of treatment and most importantly the occlusal vertical dimension and centric relation in which to plan the treatment. A systematic approach in managing these patients can lead to a predictable and favourable prognosis. This article presents the stages of prosthodontic rehabilitation, from diagnosis to final treatment and follow-up, of a bruxer patient with severely worn dentition.

Videoendoscopic measurement of food bolus formation for quantitative evaluation of masticatory function

In the field of prosthodontics, many methods for evaluating the masticatory function involve ejection of the food bolus from the mouth. In addition, these methods could not evaluate mastication and swallowing function comprehensively. The present study aimed to quantitatively evaluate masticatory functions during a series of masticatory and swallowing movements by using videoendoscopy. Subjects are ten healthy dentulous adults without dysphagia. The test foods used were 2-colored (green and white) molded rice and uirou (rice cake). The test foods were consumed under the restriction on the number of mastication (10, 15, 20, and 30), and under the instruction to "chew normally" or "chew well". The masticatory function was evaluated by observing the food bolus in the oropharynx with a videoendoscope. The bolus formation index (BFI), in terms of the degree of mixing of the green and white parts, was quantitatively determined using an image measurement software. The BFI of the rice and uirou increased significantly with increase in the number of mastication times (p<0.01). A significantly correlation coefficient was observed between the BFI and the number of mastication (0.84 for rice and 0.89 for uirou). The BFI obtained by "chewing well" was significantly higher than that obtained by "chewing normally" (p<0.01). The results of this study confirm that the endoscopic measurement of food bolus formation by mastication in terms of the color tones of 2-colored test foods enables quantitative evaluation of the masticatory function during a series of masticatory and swallowing movements.

Comparison of obturator design for acquired maxillary defect in completely edentulous patients

The most challenging and appreciated area in the field of Prosthodontics is the rehabilitation of maxillary defects. Tumors of the head and neck are the common cause for acquired maxillofacial defects. Surgical consequences predispose the patient to hypernasal speech, fluid leakage into nasal cavity, impaired masticatory function, and cosmetic deformity. The Prosthodontists play a significant role in the intervention and improve the quality of life of such patients. The current article describes two clinical case reports of completely edentulous patients with acquired maxillary defects.

Microstructure, mechanical performance and corrosion properties of base metal solder joints

Alloys have been considered to be of paramount importance in the field of prosthodontics. Long span prosthesis may often require joining of one or more individual castings to obtain better fit, occlusal harmony and esthetics in comparison to one-piece casting. This study was undertaken to evaluate the mechanical properties of base metal alloys joined by two different techniques, namely, gas oxygen torch soldering and laser fusion, compared to a one-piece casting. Mechanical properties evaluated were tensile strength, percentage of elongation and hardness of the solder joint. In addition, corrosion properties and scanning electron microscopic appearance of the joints were also evaluated. The samples were prepared according to American Society for Testing Materials specifications (ASTM, E8). Specimens were made with self-cure acrylic and then invested in phosphate-bonded investment material. Casting was done in induction casting machine. Thirty specimens were thus prepared for each group and compared with 30 specimens of the one-piece casting group. SPSS software (version 10.0, Chicago, IL, USA) was used for statistical analysis. ANOVA and Benferroni post hoc tests were done for multiple comparisons between the groups and within the groups for mean difference and standard error. Results showed that tensile strength of the one-piece casting was higher than laser fused and gas oxygen torch soldered joints. Laser fused joints exhibited higher hardness values compared to that of gas oxygen torch soldered joints. Scanning electron microscopic examination revealed greater porosity in the gas oxygen torch soldered joints. This contributed to the reduction in the strength of the joint. Gas oxygen torch soldered joints showed less corrosion resistance when compared to laser fused joints and one-piece casting. Laser fusion, which is a recent introduction to the field of prosthodontics, produces joints which have properties between those of one-piece casting and the gas oxygen torch soldering.

Probabilistic fatigue analysis of all-ceramic crowns based on the finite element method

The reliability evaluation and lifetime prediction of oral restorations for dentists have always been the major concern in the field of prosthodontics. This study introduced a new methodology for dealing with stress–strength interference and an analysis to quantify the reliability of all-ceramic crowns. The response stress was based on finite element models of all-ceramic crowns, which were constructed by reverse techniques. The method utilized in this study was a probabilistic analysis that considered the all-ceramic crown as a structural component associated with multiple factors involved in the all-ceramic system including occlusal loads and mechanical properties of porcelain. The results suggested the survival probability of all-ceramic crowns after 1, 5, 10, 15, and 20 years could be computed to be 98.89%, 98.03%, 97.50%, 97.13%, and 96.93%, respectively. Probabilistic analysis methods offer a systematic technique to incorporate and account for the nature of uncertainty in ceramic restorations and allow prediction of the reliability of all-ceramic crowns under cyclic occlusal loads with accuracy.

Lasers in prosthodontics — An overview part 1: Fundamentals of dental lasers

The introduction of lasers in the field of prosthodontics has replaced many conventional surgical and technical procedures and is beginning to replace the dental handpiece. Although lasers were introduced in dentistry as early as the 1960s it has gained widespread popularity mainly in the developed countries only from the early 90s. Today, prosthodontists can select from a variety of laser wavelengths available in dentistry. This has led to great confusion regarding laser operation and selection of the most appropriate laser wavelength for a given procedure. This article reviews literature on lasers with the aim of providing a complete understanding of the fundamentals of lasers and their applications in the various disciplines of prosthodontics. Peer reviewed literature published in English language between 1991 and 2007 obtained using Medline, and hand searches is reviewed in a series of three articles: Part 1 will describe the fundamentals of laser science, laser tissue interaction, laser wavelengths available in dentistry, laser parameters and safety measures in brief to enable the clinician to select the best laser for a certain procedure and also understand the biologic rationale for its use. Part 2 will deal in brief with the applications of lasers in the various branches of prosthodontics and their advantages over conventional techniques. Part 3 will deal with lasers in prosthodontics from an Indian perspective.