Interest In Dentistry Research Articles

Peptide-functionalized zirconia and new zirconia/titanium biocermets for dental applications

ObjectiveTitanium materials have been functionalized with biomolecules as a modern strategy to incorporate bioactive motifs that will expand and improve their biomedical applications. Here, we have biofunctionalized biomaterials based on zirconia of much interest for dentistry: the widely used bioceramic 3Y-TZP and a newly developed 3Y-TZP/Ti biocermet. MethodsThe biosurfaces were activated, silanized, and functionalized with coatings made of oligopeptides. Surface activation by plasma or alkaline-etching was optimized. The surfaces were coated by tethering a purposely-designed RGD-containing peptide. We selected this oligopeptide as a model peptide to validate the effectiveness of the biofunctionalization process. Successful treatments after each step of the process were assessed by surface physical and chemical characterization with water contact angles and XPS, respectively. Coatings’ stability was evaluated after 2h sonication in water. Pre-osteoblasts adhesion on the functionalized surfaces was also studied. Results10-min air-plasma treatment effectively activated all types of materials with no detrimental effects on the material structure and hardness. Nitrogen XPS-peak confirmed that RGD-peptides were chemically-attached on the silanized samples. This was further confirmed by visualizing the functionalized surfaces with flourescence-labelled RGD-peptides before and after ultrasonication. Furthermore, RGD-functionalized surfaces significantly enhanced osteoblast adhesion on all types of substrates, which demonstrated their successful bioactivation. ConclusionsWe successfully developed stable functional biocoatings on zirconia and biocermets made of oligopeptides. Surface bioactivation of zirconia-containing components for dental implant applications will enable their improved clinical performance by incorporating signalling oligopeptides to accelerate osseointegration, improving permucosal sealing, and/or incorporating antimicrobial properties to prevent peri-implant infections.

Material Fatigue Research for Zirconia Ceramic Dental Implant: a Comparative Laboratory and Simulation Study in Dentistry

This research focuses on the biocompatible zirconia ceramic (ZrO2) material and load behavior causing fatigue on the surface of the dental implant in dentistry. Fatigue fracture and wear have been identi ed as some of the major problems associated with implant loosening, stress-shielding and ultimate implant failure. A static and cyclic fatigue testing of ceramic dental implant in laboratory conditions for this investigation were carried out according to the ISO protocol 14801 under worst-case conditions. A nite element analysis (FEA) of dental implant with accurate geometry and material properties were developed to make realistic investigations on biocompatibility of the implant biomaterial properties and mechanical fatigue behavior of new dental implant comparing Von-Mises criteria and maximum stress levels. The comparison of calculated fatigue life simulation data of and experimental data for the biocompatible zirconia ceramic dental implants is presented. As a conclusion zirconium implant exceeded the established values for maximum incisal bite forces reported in the literature and and also shows better performance than titanium implant material. The results of fatigue of biocompatible zirconia analysis are helpful for implant biomaterial selection and design for clinical interest in dentistry.

Effect of cinnamate comonomers on the dental formulation properties

AbstractThis study reports the synthesis and characterization of two urethane dimethacrylates containing poly(ethylene oxide) or poly(propylene oxide) segment and cinnamate pendant moieties to be formulated in dental resin composites. 1H NMR, 13C NMR, and Fourier transform infrared spectroscopies, gel permeation chromatography, electrospray ionization‐mass spectroscopy, and thermogravimetric measurements confirmed their structure, whereas the photopolymerization evolution of oligodimethacrylates relating to a low–molecular‐weight dicinnamate methacrylate under ultraviolet irradiation was investigated by photo‐differential scanning calorimeter, monitoring the degree of conversion (DC) and polymerization rate. The photopolymerization results reveal that the investigated derivatives display a good photoreactivity (DC: ∼ 70%) during the formation of crosslinked polymers, the DC depending especially on the sample viscosity. The polymerization shrinkage for several mixtures including the urethane oligocinnamates (20 wt %) and diglycidyl methacrylate of bisphenol A/triethyleneglycol dimethacrylate system in the absence of filler was determined, the obtained values being in the range of 6.1–8.2 vol %. For few cured specimens incorporating quartz filler (75 wt %), water sorption/solubility, contact angle, and mechanical parameters were measured to establish if such monomers could be of interest in dentistry. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Use of Zirconia to Restore Severely Worn Dentition: A Case Report

The management of tooth wear has been a subject of increasing interest from both preventive and restorative points of view. Severe tooth wear is frequently multifactorial and variable. Successful management is a subject of interest in dentistry. A critical aspect is to determine the occlusal vertical dimension (OVD) and a systematic approach that can lead to a predictable and favorable treatment prognosis. Management of patients with worn dentition is complex and difficult. Accurate clinical and radiographic examinations, a diagnostic wax-up, and determining OVD are crucial. This paper describes the full-mouth rehabilitation of a 47-year-old bruxer with a severely worn dentition.

Full‐Mouth Rehabilitation of a Patient with Severely Worn Dentition and Uneven Occlusal Plane: A Clinical Report

Severe tooth wear is frequently multifactorial and variable. Successful management is a subject of interest in dentistry. A critical aspect is to determine the occlusal vertical dimension (OVD) and a systematic approach that can lead to a predictable and favorable treatment prognosis. Management of patients with worn dentition is complex and difficult. Accurate clinical and radiographic examinations, a diagnostic wax-up, and determining OVD are crucial. Using mini-implants as orthodontic anchorage may facilitate orthodontic movement of teeth to improve their position, which is necessary for favorable prosthetic treatment. A 46-year-old man was referred for restoration of his worn and missing teeth. After diagnostic work-up, provisional removable prostheses were fabricated for both jaws, evaluated clinically, and adjusted according to esthetic, phonetic, and vertical dimension criteria. Clinical crown lengthening and free gingival graft procedures were performed in appropriate areas. Drifting of the left posterior mandibular teeth was corrected using mini-implants as orthodontic anchorage. Two conventional implants were inserted in the right mandibular edentulous area. After endodontic therapy of worn teeth, custom-cast gold dowels and cores were fabricated, and provisional removable prostheses were replaced with fixed provisional restorations. Metal-ceramic restorations were fabricated, and a removable partial denture with attachments was fabricated for maxillary edentulous areas. An occlusal splint was used to protect the restorations. Full-mouth rehabilitation of the patient with severely worn dentition and an uneven occlusal plane was found to be successful after 3 years of follow-up. This result can encourage clinicians to seek accurate diagnosis and treatment planning to treat such patients.

U.S. Dental School Applicants and Enrollees, 2009 Entering Class

Over the past two decades, interest in dentistry in the United States has shown a steady period of growth. There were 12,210 individuals who applied to the 2009 entering class of U.S. dental schools. The number of first-time enrollees was 4,871, the highest figure since 1990. Men continue to comprise the majority of applicants and enrollees; however, the percentages of women continue to increase. While the 2009 underrepresented minority applicants comprised 12 percent of both the applicant and first-time enrollee pools, the percentage of underrepresented minority enrollees of underrepresented minority applicants decreased from 2008. Seventy-one percent of enrollees earned a baccalaureate degree in biological science or chemistry/physical science. Regardless of major fields of study, the percent rates of enrollment generally exceeded 32 percent.

Using occlusal wear information and finite element analysis to investigate stress distributions in human molars

Simulations based on finite element analysis (FEA) have attracted increasing interest in dentistry and dental anthropology for evaluating the stress and strain distribution in teeth under occlusal loading conditions. Nonetheless, FEA is usually applied without considering changes in contacts between antagonistic teeth during the occlusal power stroke. In this contribution we show how occlusal information can be used to investigate the stress distribution with 3D FEA in lower first molars (M(1)). The antagonistic crowns M(1) and P(2)-M(1) of two dried modern human skulls were scanned by μCT in maximum intercuspation (centric occlusion) contact. A virtual analysis of the occlusal power stroke between M(1) and P(2)-M(1) was carried out in the Occlusal Fingerprint Analyser (OFA) software, and the occlusal trajectory path was recorded, while contact areas per time-step were visualized and quantified. Stress distribution of the M(1) in selected occlusal stages were analyzed in strand7, considering occlusal information taken from OFA results for individual loading direction and loading area. Our FEA results show that the stress pattern changes considerably during the power stroke, suggesting that wear facets have a crucial influence on the distribution of stress on the whole tooth. Grooves and fissures on the occlusal surface are seen as critical locations, as tensile stresses are concentrated at these features. Properly accounting for the power stroke kinematics of occluding teeth results in quite different results (less tensile stresses in the crown) than usual loading scenarios based on parallel forces to the long axis of the tooth. This leads to the conclusion that functional studies considering kinematics of teeth are important to understand biomechanics and interpret morphological adaptation of teeth.

Synthesis and solubility of calcium fluoride/hydroxy-fluorapatite nanocrystals for dental applications

As the mineral phase of tooth enamel consists of apatite containing fluoride, the “CaF 2-like” salts are of significant interest in dentistry for their roles as labile fluoride reservoirs in caries prevention. Fluoride ion is required for normal dental development because of its therapeutic ability of osteoporosis healing and stimulating osteoblast activity both in vitro and in vivo. In this research, biphasic Calcium fluoride/fluorinated-hydroxyapatite (CF/FHAp) nanocrystals have been successfully synthesized via co-precipitation method. The synthesized powder was characterized by the commonly used bulk techniques such as chemical analysis, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray powder diffraction (XRD) analyses. The obtained results confirmed the formation of biphasic powder composed of about 46% CF and 54% (w/w%) apatite phase which was a solid solution composed of more than 50% fluorapatite (FAp). In addition, in vitro evaluations of the powder were performed, and for investigating their bioactive capacity they were soaked in simulated body fluid (SBF) at different time intervals. The samples showed significant enhancement in bioactivity within few hours of immersion in SBF solution. Also, the EDS analysis clearly showed dissolution and deposition of calcium and phosphate ions on the surface of synthesized biphasic powder after the first week of immersion in SBF solution.

The Saudi Dental Journal’s mission for the Saudi Dental Society

The Saudi Dental Society (SDS) is a community of dental professionals whose mission is to diffuse awareness of and interest in dentistry, promote scientific research in the fields of dentistry and establish a closer relationship amongst its members locally and internationally. These are the missions I plan to achieve in my service as the Society’s current President for which I am honored and count as a privilege. The Saudi Dental Journal was established to serve as the official publication of the Saudi Dental Society to achieve the Society’s purpose in promoting scientific research by means of publishing scientific articles in a journal. To fully serve the almost 2500 current active SDS members, the Society has given its extensive support to the Saudi Dental Journal to help achieve its objective. The Saudi Dental Journal is accessible online free of charge, a benefit offered to all its members. After facing challenges and identifying expectations, the Saudi Dental Journal under the new editorship of Prof. Khalid Al-Wazzan made extensive efforts to conduct a benchmark exercise to obtain its strategic objectives and to ensure the Journal becomes an internationally recognized journal. The Saudi Dental Journal has experienced unprecedented development and transformation as it accelerates its ambition to be of international standard. To start with, the Journal is now officially published by King Saud University Academic Press and Elsevier B.V. who also provided the online editorial system. The Journal had achieved substantial results towards fulfillment of its major objectives. From the time it commenced its submission and review process online through Elsevier Editorial System, the number of submitted manuscript for publication escalated to almost a hundred percent in just several months. The duration from submission to decision process was significantly reduced. The quality of submitted articles has also improved. The Saudi Dental Journal is continually making efforts to improve its standard and is currently pursuing its mission to apply to the ISI Web of Knowledge and Medline. Colleagues and members of the Society can openly support the Journal by publishing upcoming quality research manuscripts as well as cite recently published articles from the Saudi Dental Journal. Articles can be viewed from the following URLs: http://www.sdsjournal.org/saudi-dental-journal.html http://www.sciencedirect.com/science/journal/10139052 http://www.ees.elsevier.com/sdentj/ The Saudi Dental Society strives to give power to the dental population through a novel and varied approach which is reflected in the community we serve. We express our principles through veracity and concern, and promoting social responsibility. As members, we should be determined to take a strong step ahead to develop our systems and to improve ourselves as dentists.

Nanodentistry – The New Horizon

Developments in dentistry, driven by years of research, have made dental procedures less painful, fast, reliable, effective and safe. Innovative technologies such as digital dentistry, lasers, cosmetic dentistry, implants, nanotechnology, and nanorobots have had a significant impact on the dental equipment and efficiency of dental personnel. Nanotechnology in particular, has emerged as a promising area of interest in dentistry due to the variety of new treatment options it offers. Nanodentistry will make possible the maintenance of near-perfect oral health and oral health trends will change the focus on specific diagnostic and treatment modalities.

Ortodontia como fator de risco para disfunções temporomandibulares: uma revisão sistemática

INTRODUÇÃO: nos últimos anos, a inter-relação entre a Ortodontia e as disfunções temporomandibulares (DTMs) tem despertado interesse crescente na classe odontológica, sendo tema de discussões e controvérsias. Em um passado recente, a oclusão era considerada como principal fator etiológico das DTMs, sendo o tratamento ortodôntico uma medida terapêutica primária para um restabelecimento fisiológico do sistema estomatognático. Assim, passou-se a investigar o papel da Ortodontia na prevenção, desencadeamento e tratamento das DTMs. Com a realização de estudos científicos com metodologias mais rigorosas e precisas, a relação entre o tratamento ortodôntico e as DTMs pôde ser avaliada e questionada dentro de um contexto baseado em evidências científicas. OBJETIVO: o presente trabalho, através de uma revisão sistemática de literatura, teve como objetivo analisar a inter-relação entre a Ortodontia e as DTMs, verificando se o tratamento ortodôntico é fator contribuinte para o desenvolvimento de DTM. MÉTODOS: foi realizado um levantamento em bases de pesquisa (Medline, Cochrane, Embase, Pubmed, Lilacs e BBO) entre os anos de 1966 e 2009, com enfoque em estudos clínicos randomizados, estudos longitudinais prospectivos não randomizados, revisões sistemáticas e meta-análises. RESULTADOS: após a aplicação dos critérios de inclusão, chegou-se a 18 artigos, sendo que 12 eram estudos longitudinais prospectivos não randomizados, 4 revisões sistemáticas, 1 estudo clínico randomizado e uma meta-análise, os quais avaliaram a relação entre tratamento ortodôntico e DTM. CONCLUSÕES: pela análise da literatura, conclui-se que o tratamento ortodôntico não pode ser considerado fator contribuinte para o desenvolvimento de disfunções temporomandibulares.

U.S. Dental School Applicants and Enrollees, 2008 Entering Class

Over two decades, interest in dentistry in the United States has shown a steady period of growth. Nearly 12,200 individuals applied to the 2008 entering class of U.S. dental schools, while the number of first‐time enrollees was 4,794, the highest figure since 1990. Men continue to comprise the majority of applicants; however, the percentage of women applicants continues to increase. Underrepresented minority applicants comprised 12 percent of both the applicant and first‐time enrollee pools. The largest number of applicants came from states that are among those with the largest populations in the United States: California, New York, Florida, and Texas. Nearly four out of five enrollees earned a baccalaureate degree in biological science, chemistry/ physical sciences, or pre‐dentistry. Regardless of major fields of study, the percent rates of enrollment generally exceeded 34 percent. The majority of applicants and enrollees placed in the upper GPA and Dental Admission Test (DAT) percentiles. The average age of 2008 enrollees was twenty‐four years.

Accreditation of Dentist Anesthesiologist Residencies is Approved by CODA

Accreditation of Dentist Anesthesiologist Residencies is Approved by CODA

The Hungarian version of the Oral Health Impact Profile

Oral health-related quality of life (OHRQoL) is increasingly of interest in dentistry. The current internationally accepted instruments used to measure OHRQoL need to be cross-culturally adapted for use in other cultural environments. It was the aim of the present study to develop a Hungarian version of the Oral Health Impact Profile (OHIP-H) following accepted guidelines. The original English-language version was translated into Hungarian, back-translated into English, and tested for its psychometric properties. Construct validity was tested on 144 prosthodontic patients and 200 randomly selected subjects. A priori hypothesized associations between OHIP summary scores and self-reported oral health and six self-reported oral conditions were investigated. The pattern of the observed associations supported the new instrument's construct validity. Responsiveness tested in 28 oral surgery patients was indicated by a statistically significant mean OHIP score change from 39.2 to 23.0. Test-retest reliability was demonstrated by intraclass correlation coefficients of 0.81-0.90 for OHIP summary scores and subscales in 31 prosthodontic patients. Cronbach's alpha values between 0.71 and 0.96 proved to have high internal consistency. Adequate psychometric properties in typical patient populations make the new instrument suitable for assessment of OHRQoL in Hungary.

Temporomandibular Joint, Disorders and Approaches

ABSTRACTThe study of temporomandibular joint (TMJ) and its relationship to function of the stomathognathic system has been a topic of interest in dentistry for many years. This relationship has proved to be quite complex. The TMJ is certainly one of the most complex joints in the body. As knowledge of the anatomy and physiology of the TMJ increases, and instruments and techniques for measuring dynamic skull-fossamandibular factors are developed, many more general dentists are attempting to—and are expected to- diagnose and treat TMJ-oriented problems. Temporomandibular disorders (TMD) include clinical disorders involving the masticatory muscles, the TMJ and the adjacent structures. TMD was recognized as a main source for pains in the orofacial area, which are not caused from dental origin, and is defined by the American Academy of Orofascial Pain (AAOP) as a sub-group within the frame of musculoskeletal disorders. The main etiology for TMD has not been found yet.

Appraisal of the Dental School Learning Environment: The Students’ View

The majority of studies examining dental school curriculum have addressed organization, structure, and content issues from the perspectives of administrators, faculty, practitioners/alumni, and professional organizations. However, few studies have focused on students' opinions of dental school. The purpose of this study was to determine students' perceptions of the learning environment, intellectual climate, and teacher-student relationships in dental school. This report describes how the "dental version" of the Medical Student Learning Environment Survey (MSLES) was used to identify students' perceptions of their dental education. Freshman and junior dental students' perceptions were measured with the Dental Student Learning Environment Survey (DSLES), which evaluates learning environment, intellectual climate, and relationships among students and teachers in seven areas: flexibility, student-to-student interaction, emotional climate, supportiveness, meaningful experience, organization, and breadth of interest. The DSLES was mailed to twenty-three dental schools in North America with eighteen of the schools distributing the inventory. A total of 619 dental students responded. Results were differentiated between freshman and junior dental students. Both freshman and junior students provided the highest (most positive) ratings for the DSLES subscales of "breadth of interest" (interest in dentistry and outside interests are encouraged) and "meaningful learning experience" (significance of courses to dentistry). Freshman students provided the lowest (least positive) ratings for "emotional climate" (students' responses to the way their courses were conducted and stress levels), and junior students provided the least positive ratings for "faculty supportiveness" (extent of faculty support and encouragement provided to students). The DSLES identified students' perceptions of their educational experience and localized areas for improvement. By addressing these areas of concern, faculty can increase student satisfaction with their dental education.

Predental Enrichment Activities of U.S. Colleges and Universities

The purpose of this study was to examine predental enrichment activities and their impact on the number of applicants from some of the nation's top dental school feeder institutions (DSFI). The DSFI were identified by their total number of applicants to dental schools and the number of applicants per total student enrollment. A survey consisting of twenty-seven questions on possible predental enrichment activities was administered by phone or sent by email to eighty-eight DSFI, with forty-nine responding. In addition to identifying and characterizing the most common predental enrichment activities, the relationships among the number of applicants, predental activities, and total student enrollments per institution were evaluated. The total number of dental school applicants/institution was correlated with the total student enrollment/institution (r=0.529) and the number of predental activities/institution (r=0.520). No correlation was observed between the number of activities at an institution and dental school applicants per thousand enrolled. Sixteen of the DSFI reported ten or more enrichment activities, the most common being preprofessional health advising (96 percent), dentistry club (88 percent), and volunteer programs (73 percent). In general, larger institutions produced more applicants and provided more enrichment activities. However, there was no correlation between the number of dental school applicants per thousand students enrolled and the number of activities at an institution. Results indicate that there are specific predental enrichment activities common to some of the top dental school feeder institutions in the United States. A better understanding of successful feeder programs may assist nonfeeder schools in developing or strengthening an interest in dentistry as a career option.

Positive effect of early loading on implant stability in the bi‐cortical guinea‐pig model

Loading, early after implant placement, has gained rapid interest in dentistry. Primary implant stability, as e.g. defined by resonance frequency instrumentation, has been isolated as a predicator when immediate and early implant loading is applied. The aim of this study was to investigate the effect of early (after 7 days) mechanical loading on the establishment of osseointegration by means of resonance frequency analysis (RFA). Percutaneous titanium implants were installed in both tibiae of 10 guinea-pigs. One week after implant installation, one implant (test) was loaded daily for 6 weeks, while the contra-lateral served as the unloaded one (control). A sinusoidally varying bending moment was applied at a frequency of 3 Hz and a force amplitude of 5 N, for 1800 cycli. Resonance frequency was measured at implant installation and from then on weekly using the RFA-device (Osstell). Contrary to control implants, that showed a decrease in stability 1 week after installation, reaching a minimum at 3 weeks (-200 Hz), test implants showed a progressive increase in stability over time. After 6 weeks, the mean resonance frequency of test and control implants reached the same values. As confirmed by recent literature, early loading does not have to endanger the establishment of osseointegration of titanium implants. On the contrary, controlled loading is beneficial to maintain the implant stability during the early critical healing period as determined by RFA-measurements.

The future of the profession — a survey of dental school applicants

To gather background information about applicants to the dental undergraduate course, and ascertain the factors involved in their decision to study dentistry. Applicants attending for interview at Dundee and Manchester Dental Schools completed anonymous questionnaires. The useable response rate was 94% (n = 436). There were equal numbers of male and female applicants to the two schools as a whole. Although there was a much broader ethnic mix in the applicants to Manchester, the overall proportion of minority ethnic groups was considerably greater than in the UK population as a whole. Seventy-five per cent came from professional backgrounds, although marked differences were apparent between ethnic groups. A quarter had family relations who were dentists, and 30% were related to doctors. Over half (53%) decided to apply within the last year, with popular motivating factors including a general interest in dentistry, a desire to help people and to work with their hands. Dentistry was the first choice of career of 89%, with medicine the most popular alternative. Valuable information was gathered from these prospective dental students regarding their backgrounds and the decision process involved in their career selection. This will prove beneficial when developing the recruitment process and allow appropriate tailoring to the target audience.

Promoting dentistry as a career: a local initiative.

This was to ascertain reasons for pupils' interest in dentistry, and what appealed to them from their current knowledge of the profession. The findings were compared with those of undergraduates and practising dentists. Three different groups of subjects (school pupils, fourth-year dental undergraduates and general dental practitioners) in West Yorkshire were asked to complete a single-sided A4 questionnaire. All respondents completed the questionnaire fully. Promotion of dentistry as a career should be targeted at the 14-15-year-old age group and above. Advice on a career in dentistry may be sought from general dental practitioners (who should keep up to date with dental degree/career information), careers fairs, and written information (which should be well-presented and informative). Dental schools might provide information via 'predental advisers' and recruiting courses, with help for applicants from professionals with relevant experience.