Dental Dam and Isovac Usage: Factors Influencing Dental Students' Decisions on Isolation Techniques.

The Isovac system was introduced into the Virginia Commonwealth University dental curriculum with the intention that it would be used as a substitute when the dental dam could not be placed. The aim of this study was to determine the usage and factors that influenced dental students' decisions to use the dental dam or Isovac. All third-and fourth-year dental students (n=210) were asked in 2017 to complete a 26-item survey. The survey asked about students' operative procedures completed using the dental dam and Isovac, their own and their patients' preferences, basic dental dam knowledge, full-time and adjunct faculty recommendations of method, importance of factors influencing their decisions, and anticipated dental dam use after graduation. Comments were also allowed. A total of 164 students responded to the survey, for a 78% response rate. Of the respondents, 58% said they used the Isovac only when they could not use the dental dam. Among the eight general practice groups in which students are educated in delivery of comprehensive dental care, preference was significantly different for placement of Class II restorations. Overall, the students' dental dam knowledge was low, and the knowledge results were not associated with its use. According to the students, recommendations by full-time and adjunct faculty members were significantly different. Factors ranked by importance from greatest to least for determining which isolation method to use were as follows: moisture control, procedure, patient comfort, application time, ease of placement, and attending faculty. Student comments overwhelmingly favored dental dam usage if a dental assistant was available. This study found that dental dam and Isovac use was not standardized among the general practice groups and faculty. Student education, faculty calibration, and increased use of trained dental assistants are required to ensure education is consistent among all general practice groups.

Eficácia entre dois localizadores apicais eletrônicos testados no nível do forame e ultrapassando e retornando ao forame / Effectiveness between two electronic apex locators tested at foramen level and passing through and returning to the foramen

Introdução: O localizador apical eletrônico é uma ferramenta que facilita o tratamento endodôntico. O objetivo do presente estudo foi avaliar, in vitro, a precisão de dois localizadores apicais usados de duas maneiras distintas. Material e métodos: As medidas reais de 20 molares inferiores extraídos de humanos foram determinadas, posicionando-se os instrumentos até o forame, auxiliados por um microscópio clínico com 20x de aumento. As medidas foram realizadas com um paquímetro. Feito isso, os dentes foram montados em uma plataforma de polietileno, posicionada dentro de uma cuba plástica contendo gelatina preparada com soro fisiológico e, então, as medidas eram realizadas com os localizadores Novapex e Root ZX, posicionando os instrumentos na posição zero ou passando com o instrumento além do zero e voltando a essa posição. Para a análise dos resultados foi usada a diferença das duas medidas (real do dente e obtida pelo aparelho). Resultados: Os dados das raízes distais e mesiais foram submetidos à análise estatística. Na raiz distal o teste Anova mostrou diferença significante entre os grupos (p<0,01) e o teste de Tukey demonstrou diferença entre os valores do Novapex passando e do Root ZX na posição zero. Na raiz mesial, o teste Anova não mostrou diferença significante entre os grupos (p>0,01). Conclusão: Conclui-se que quando se usou a técnica de ir até o zero, o aparelho Novapex mostrou-se mais preciso, porém na técnica de passar e retornar ao zero, o aparelho mais preciso foi o Root ZX (AU)

Introduction: The electronic apex locator is a tool that facilitates endodontic treatment. The aim of this study was to evaluate in vitro the accuracy of two apex locators used in two different ways. Methods: Real measurements of 20 lower molars extracted from human were determined by positioning the instruments until the foramen aided by a 20x clinical microscope. The measurements were taken with a caliper. After this, the teeth were mounted on a polyethylene platform, positioned inside a plastic tub containing gelatin prepared with saline and the measures were carried out with the locators Novapex and Root ZX positioning instruments in zero or passing with the instrument beyond zero and returning to this position. The difference between the two measurements (real tooth and obtained by the device) were used for results analysis. Results: Data from the distal and mesial roots were subjected to statistical analysis. In the distal root, ANOVA showed significant difference between groups (p <0.01) and Tukey's test showed difference between the Novapex values ​when passing and Root ZX in zero. At the mesial root, ANOVA showed no significant difference between groups (p> 0.01). Conclusion: It was concluded that when using the technique positioning instruments in zero the Novapex was more accurate, however when the technique was to pass and to return to zero, the most accurate device was the Root ZX (AU)

Economic impact of dental hygienists on solo dental practices.

The fact that a significant percentage of dentists employ dental hygienists raises an important question: Are dental practices that utilize a dental hygienist structurally and operationally different from practices that do not? This article explores differences among dental practices that operate with and without dental hygienists. Using data from the American Dental Association's 2003 Survey of Dental Practice, a random sample survey of U.S. dentists, descriptive statistics were used to compare selected characteristics of solo general practitioners with and without dental hygienists. Multivariate regression analysis was used to estimate the effect of dental hygienists on the gross billings and net incomes of solo general practitioners. Differences in practice characteristics--such as hours spent in the practice and hours spent treating patients, wait time for a recall visit, number of operatories, square feet of office space, net income, and gross billings--were found between solo general practitioners who had dental hygienists and those who did not. Solo general practitioners with dental hygienists had higher gross billings. Higher gross billings would be expected, as would higher expenses. However, net incomes of those with dental hygienists were also higher. In contrast, the mean waiting time for a recall visit was higher among dentists who employed dental hygienists. Depending on personal preferences, availability of qualified personnel, etc., dentists who do not employ dental hygienists but have been contemplating that path may want to further research the benefits and opportunities that may be realized.

Musculoskeletal disorders amongst practising South African oral hygienists.

OBJECTIVES: The study sought to determine the level of musculoskeletal disorders among working oral hygienists in South Africa and potential determinants that are associated with these disorders. METHODS: Oral hygienists registered with the HPCSA were requested to complete an anonymous questionnaire. Apart from demographic information they were asked to report on any musculoskeletal symptoms experienced in the hands, neck, shoulders and lower back as well as details of workload, types of scaling procedures, size of instruments, the mobility of the operator's chair and the adjustability of patient chairs. RESULTS: Of the 362 respondents, 61.3%, 66.5%, 56.6% and 59.6%, experienced hand, neck, shoulder and lower back symptoms respectively. Twenty-eight percent of the respondents performed hand-scaling for more than four hours per day. Twenty-six percent reported immobile operator chairs, while 12.6% reported patient chairs that were difficult to adjust. Employing multivariate analysis, excessive hand scaling was associated with hand and shoulder symptoms, while immobile operator's chairs and poorly adjustable patient chairs were respectively associated with neck and lower back problems. CONCLUSIONS: The prevalence of work-related musculoskeletal disorders in practising oral hygienists in South Africa appears to be similar to that in developed countries. Significant determinants of musculoskeletal disorders may be immobile operator stools, poorly adjustable patient chairs and excessive hand-scaling daily.

Computer and Internet usage by Canadian dentists.

OBJECTIVES: To determine the frequency of computers in Canadian dental offices and to assess their use; to evaluate Internet access and use in Canadian dental offices; and to compare use of computers and the Internet by Canadian dentists, by the general public and by other dental groups. METHODS: An anonymous, self-administered survey of Canadian dentists was conducted by mail. A potential mailing list of 14,052 active Canadian dentists was compiled from the 2003 records of provincial regulatory bodies. For each province, 7.8% of the general dentists were randomly selected with the help of computer software. The surveys were mailed to this stratified random sample of 1,096 dentists. RESULTS: The response rate was 28%. Of the 312 respondents, 4 (1%) were in full-time academic positions, 15 (5%) were not practising, and 9 (3%) provided incomplete data. Therefore, 284 survey responses were available for descriptive analysis. Two hundred and fifty-seven (90%) of the respondents had a computer in their primary practice. Computers were used mainly for administrative tasks (accounting, bookkeeping and scheduling) rather than clinical tasks. Internet access was common (185/250 or 74%), and high-speed Internet access (93/250 or 37%) was increasingly common, judging from the results of previous studies on computer use. The main reasons given for not having in-office Internet access were security or privacy concerns and no reported need for or interest in the service. CONCLUSIONS: Computer use was high in this sample of Canadian dentists, but a small proportion of dental offices remained without computers. Canadian dentists" use of the Internet was greater than that of American dentists, private enterprise and the North American public in general.

The importance of productivity in estimating need for dentists.

BACKGROUND: Although the number of dentists is an important determinant of supply, other factors also contribute. Technological advancements and well-trained and managed auxiliary personnel affect supply by allowing dentists to produce more dental services per unit of time. METHODS: This article examines trends in dental output, productivity, number of dentists and dental care utilization from 1960 through 1998. The authors estimated growth rates for the entire period and selected subperiods using regression analysis. Growth rates for dentist productivity and per capita utilization are important to estimate the number of active dentists needed in the year 2020. RESULTS: Based on ADA practice survey data, the annual growth rate in dentists' productivity was 1.41 percent from 1960 through 1998. However, productivity grew at different rates during this period. It increased 3.95 percent per year from 1960 to 1974. There was a decline in productivity of 0.13 percent annually from 1974 to 1991. From 1991 to 1998, productivity grew 1.05 percent annually. CONCLUSIONS: Accurate estimates of changes in dentist productivity are important in evaluating the adequacy of the number of dentists to meet the demand for dental services. PRACTICE IMPLICATIONS. Since productivity generally increases over time, failure to account for changes in productivity can lead to an overestimation of the number of dentists required for any given level of demand for dental services.

Disability part 2: access to dental services for disabled people. A questionnaire survey of dental practices in Merseyside.

This article aims to identify how accessible general dental practitioners thought that their services were and to identify the barriers they face in providing care for disabled people. A postal questionnaire survey was undertaken of all general dental practices in the Liverpool, Sefton, St Helens and Knowsley Health Authorities. Only one quarter of practices described themselves as having full physical access for disabled patients. However, despite this, over 90% of practices reported treating disabled patients and most were willing to treat more disabled patients. Dentists identified physical barriers, lack of time and the lack of domiciliary equipment as the main barriers to providing care for disabled people. Although dentists were willing to treat disabled patients few dental practices were accessible at the time of the survey. Further work is needed to ensure that dental practices comply with the Disability Discrimination Act.

Development and application of a new abrasion testing device.

STATEMENT OF PROBLEM: Wear of gypsum materials is a significant problem in the fabrication of accurately fitting cast prosthetic devices. Unfortunately, there is little agreement on how to measure it. PURPOSE: This study was designed to evaluate the efficacy of a newly designed abrasion device and to develop a test methodology that provides a clinically relevant measure of material loss from gypsum material. MATERIAL AND METHODS: In this study, a unique benchtop microabrasion/microimpact device was created. The device consists of a vertical arm with a variably loaded stylus and a reciprocating table that moves the specimen under the stylus. Type IV gypsum samples (Silky Rock, Whip Mix Corp, Louisville, Ky.) were made with 1 mm vertical, 45-degree angled ridges used to represent crown margins. Samples (n = 30) were separated 1 hour after pouring and allowed to bench set for 24 hours or 7 days. Three loads (15, 50, and 75 g) were used, and the resulting defect was evaluated after 5, 10, 15, or 20 cycles of loading. Changes in mass and volume were recorded. RESULTS: At both 24 hours and 7 days, there was an increase in both mass and material volume loss with increasing load on the stylus (P<0.0001). There was no significant change in mass after 5 cycles of loading (P<0.05), but an increase in the volume loss occurred because of compaction of the walls of the defect (P<0.0001). CONCLUSION: Under these conditions, the increasing load had a greater effect than the number of load cycles on gypsum brittle fracture.

Biological monitoring of sterilizers and sterilization failures in Norwegian dental offices in 1985 and 1996.

It is essential that dental office sterilizers be regularly challenged with biological indicators (BIs) in order to prove that the test spores are being killed during sterilization. The aims of the study were to biologically monitor Norwegian dental office sterilizers and to identify factors contributing to sterilization failure. In 1985, participants received a packet containing: (i) 4 BI units; (ii) a set of instructions; (iii) a questionnaire concerning operation (including biological monitoring) of the office sterilizer(s), and (iv) a return-address envelope. In 1996, offices were sent (i) a survey which included demographic questions and inquiries concerning instrument sterilization processes; (ii) 2 sets of 3 BI units with instructions for their use on 2 different days; (iii) 1 control BI unit that was not to be processed, and (iv) a return-address envelope. Both private and public offices participated. Response rate to the 1996 study was 60%, which was 9.1% of all dental offices in Norway. Testing results indicated a 6.3% overall sterilization failure rate. Three out of 163 steam autoclaves (SAs) (1.8% of total) and 14 out of 109 dry heat (DH) ovens (12.8% of total) failed. DH ovens were over 7 times more likely to fail BI testing than were SAs (chi2, P < 0.01). Demographic or hygiene procedural factors could not be correlated to sterilization performance (chi2, P > 0.05). The failure rate for SAs (n = 216) in 1985 was almost 5 times greater than in 1996 (8.8% vs 1.8%). Improvement in sterilizer performance during the decade may be related to issuance in 1986 of Norway's 1st infection control guidelines for dentistry and greater awareness of infection control practices and/or to increases over the previous 10 years in the number of postgraduate courses offered in infection control. The current Norwegian guidelines on infection control practices in public health services, including dentistry, recommend regular biological monitoring of sterilizers without specifying how often. There is a lack of information among Norwegian dentists as to how frequently dental office sterilizers should be regularly monitored by BI.

Performance and reproducibility of a laser fluorescence system for detection of occlusal caries in vitro.

The diagnosis of occlusal caries at non-cavitated sites remains problematic, especially since clinical visual detection has limited sensitivity. Electrical methods of detection show considerable promise, but specificity is reduced. The aims of this in vitro study were: (1) to assess the validity of a new laser fluorescence device--the DIAGNOdent--(and compare the values with those of a fixed-frequency electrical device); (2) to determine the optimum cut-off points of the new device for different stages of the caries process, and (3) to assess the reproducibility of the new laser device. For validity and determination of optimum cut-off points, 105 extracted teeth with macroscopically intact occlusal surfaces were measured by a single examiner, using both the laser fluorescence device (on both moist and dried teeth) and an Electronic Caries Monitor. The teeth were subsequently examined histologically to determine the specificity, sensitivity and likelihood ratio at the D2 (caries extending through more than half of the enamel thickness) and D3 (caries involving dentin) levels. The values obtained for the laser device ranged from 0.72 to 0.87 (specificity), 0.76 to 0.87 (sensitivity) and 3.0 to 5.6 (likelihood ratio). Those for the ECM ranged from 0.64 to 0.78 (specificity), 0. 87 to 0.92 (sensitivity) and 2.4 to 4.1 (likelihood ratio). To determine intra- and interexaminer reproducibility of the DIAGNOdent, 11 dentists recorded two different measurements at the same site on a separate set of 83 extracted molar teeth, and these were compared using Cohen's kappa (at D2 and D3 levels) and Spearman's correlation coefficient. The average intra-examiner kappa scores were 0.88 (D2) and 0.90 (D3), with a Spearman correlation of 0.97. For interexaminer reproducibility, the average kappa values were 0.65 (D2) and 0.73 (D3), with a Spearman correlation of 0.84. It is concluded that for occlusal caries (1) the new laser device has a higher diagnostic validity than the ECM, and (2) in vitro, measurements using the device are highly reproducible. Thus, the laser device could be a valuable tool for the longitudinal monitoring of caries and for assessing the outcome of preventive interventions.

[The type testing of light-polymerization equipment, II: the 1998 status]. / Typenprüfung von Lichtpolymerisationsgeräten II: Stand 1998.

In this study 16 different light curing units, available on the Swiss market, were tested for their features, radiant power and light distribution across the face of the curing tip and components like integrated radiometer, timer and cooling device. The basis of this study was the test protocol published in the november edition (11/1999). The features of the light curing units differed from one another. The Optilux 500 had all conceivable features that it could be designated the standard in features. If all these technical options are necessary has to be decided by the consumer. However, the components such as the timer, radiometer and voltage stabilizer are important because they influence the time of irradiation and the radiant power. The radiant power (mW) i.e., the radiance (mW/cm2) were measured in 2 spectral areas which are important for visible light polymerisation. The absolute values for the standard curing tip at a voltage of 230 V lay between 143.4 and 389.7 mW for the wavelengths between 400-520 nm and between 17.7 and 41.8 mW for the wavelengths between 462-472 nm. The resultant specific radiance values were between 268.3 and 862.6 mW/cm2 in the broad spectrum of 400-520 nm and 33.5 and 95.4 mW/cm2 in the narrow spectrum of 462-472 nm. Where the standard curing tips were replaced by guides with other diameters, tips with larger entrances showed more radiant power, light guides with smaller exits also showed more radiance. Turbo tips have larger entrances than exits and therefore combine both positive effects. The intensity wasn't distributed equally across the face of the curing light guide. Characteristically there was a concentric distribution of the intensity, with the maximum found in the centre and a decrease to the margin. Corresponding to the radiance values, curing light tips with decreasing diameters showed more homogeneous distribution patterns. Only Turbo tips showed worse distribution. Comparing the light intensity at a voltage of 207 V and 244 V to the normal voltage of 230 V it was found that not all curing units had an integrated voltage stabilizer. Just 9 out of the 16 tested units had an integrated radiometer. Comparison of the evaluated radiance values to the values given by the integrated radiometer revealed an agreement in just two cases. The marginal values, programmed by the manufacturer varied between 70 and 300 mw/cm2 and lie therefore, too low.

Evaluation of curing units used in private dental offices.

It is well known that numerous factors influence the light output of curing units, but many dentists are unaware that the output of their curing lights are inadequate. This study was conducted to evaluate the light intensity of visible-light curing units in private dental offices and to assess their curing efficiency by measuring compressive strength of a light-cured resin. Also, in order to determine the maximum light intensity of the curing units, lamps, filters, and fiber optic bundles were replaced by new ones and curing efficiency remeasured. Light intensity was measured by employing a Quantum Radiometer LI-189 at a wavelength of 470 +/- 40 nm using a bandpass filter. Compressive strength of a light-cured resin using the light units was measured employing an Instron Testing Machine at a crosshead speed of 1.0 mm/min. From the evaluation of 105 light units, the light intensity ranged from 28 to 1368 W/m2 (0 approximately 500 W/m2; 41.9%, 500 approximately 1000 W/ m2; 45.7%, 1000 approximately 1500 W/m2; 12.4%). Light intensity of the light unit in private offices decreased 15.9 approximately 82.1% compared to brand-new units. Reduction of light intensity impaired compressive strength of the light-cured resin to varying degrees (148.3 approximately 279.9 MPa) compared with the highest value (317 MPa) obtained from brand-new light units. The replacement of the parts increased the light intensity, with maximum increases of 36.0% for lamps, 157.7% for filters, 46.2% for fiber optics, and 322.7% for all three parts. The results of this study indicated that the light intensities of the curing units used in private practice were lower than expected.

Aparelhos de fotopolimerizaçäo e o comportamento clínico das restauraçöes / Curing units equipments and the restorations clinical conduct

A resinas restauradoras fotopolimerizáveis permitiram uma revoluçäo na forma de restaurar os dentes, entretanto, a utilizaçäo de um aparelho de fotopolimerizaçäo, indispensável para o processo de "endurecimento" do material, trouxe outras preocupaçöes para o dia-a-dia do consultório. Realizamos uma coleta de dados junto a um grupo de Cirurgiöes Dentistas de origem heterogênea, onde foi possível perceber um certo descaso ou desconhecimento das variáveis envolvidas neste processo (técnica de polimerizaçäo, aparelho de polimerizaçäo e material utilizado). É objetivo deste artigo revisar a Literatura com respeito a essas variáveis, destacando o controle da intensidade de luz do aparelho como fator prepoderante dentro deste processo e demonstrar como estas variáveis podem afetar negativamente a performance clínica das restauraçöes realizadas com resinas compostas

Aparelho de raios X odontológico: avaliaçäo densitométrica da radiaçäo de fuga do receptor da imagem / Dental X-ray equipment: densitometric evaluation of leaking radiation

Com a finalidade da avaliar a segurança na utilizaçäo dos aparelhos de raios X odontológicos no tocante à emissäo de radiaçäo vazante (radiaçäo de fuga), foram avaliados 08 aparelhos de raios X odontológicos utilizados rotineiramente em uma instituiçäo de ensino, utilizando-se, para isso, análise densitométrica em filmes radiográficos expostos à radiaçäo emitida pelos referidos aparelhos. Ficou constatado que todos os aparelhos utilizados no experimento estäo emitindo radiaçäo de fuga acima dos níveis preconizados na N.I.P. (Normas Internacionais de Proteçäo)

A metal halide light source for laboratory curing of prosthetic composite materials.

A high-intensity laboratory photo-curing unit has been developed with the aim of improving the post-curing properties of composite veneering materials. This study introduces the structure of the curing unit and examines the resulting properties of a representative composite material. The curing unit is equipped with two metal halide lamps that radiate both ultraviolet and visible light. Unlike conventional metal halide lamps for industrial use, these metal halide lamps radiate an increased intensity of visible radiation. Properties of a microfilled composite veneering material cured with the new metal halide unit were ascertained. A xenon photo-curing unit was also used as a control. The specimens cured with the metal halide unit exhibited greater Knoop hardness numbers and flexural moduli as compared with those cured with the xenon unit, and also showed reduced water solubility values. These results suggest that the metal halide light source is effective in curing composite materials within a shorter period of time and with improved conversion.

Effectiveness of light-curing units in vocational training practices. A project administered by the Research Committee of the Faculty of General Dental Practitioners (UK).

A project has been organised by the Research Committee of the Faculty of General Dental Practitioners (UK) in conjunction with vocational training advisers in which vocational dental practitioners (VDPs) tested the effectiveness of the light-curing units in their surgeries using Heliotests (Ivoclar-Vivadent) and Z100 Composite (3M). The VDPs also completed a questionnaire giving details of their light-curing units. The mean incremental depth stated as being used by the respondents was 2.6 mm; 43.5% of the participants' light-curing units (n = 63) were found to produce a depth of cure less than this figure. However, no correlation was found between reported post-operative clinical problems and cure depth lower than 2.6 mm. A negative correlation between depth of cure and age of light-curing unit was noted, with older units tending to cure the composite samples to less depth than newer units (p = 0.002). One-fifth of the participating VDPs' practices had some means of checking curing-light effectiveness. Greater awareness of the need to monitor practice light-curing units is therefore required.