Bond strength of etch-and-rinse and self-etch adhesive systems to enamel and dentin irradiated with a novel CO2 9.3 µm short-pulsed laser for dental restorative procedures.

The objective of this study was to evaluate the influence of CO2 9.3 µm short-pulsed laser irradiation on the shear bond strength of composite resin to enamel and dentin. Two hundred enamel and 210 dentin samples were irradiated with a 9.3 µm carbon dioxide laser (Solea, Convergent Dental, Inc., Natick, MA) with energies which either enhanced caries resistance or were effective for ablation. OptiBond Solo Plus [OptiBondTE] (Kerr Corporation, Orange, CA) and Peak Universal Bond light-cured adhesive [PeakTE] (Ultradent Products, South Jordan, UT) were used. In addition, Scotchbond Universal [ScotchbondSE] (3M ESPE, St. Paul, MN) and Peak SE self-etching primer with Peak Universal Bond light-cured adhesive [PeakSE] (Ultradent Products) were tested. Clearfil APX (Kuraray, New York, NY) was bonded to the samples. After 24 h, a single plane shear bond test was performed. Using the caries preventive setting on enamel resulted in increased shear bond strength for all bonding agents except for self-etch PeakSE. The highest overall bond strength was seen with PeakTE (41.29 ± 6.04 MPa). Etch-and-rinse systems achieved higher bond strength values to ablated enamel than the self-etch systems did. PeakTE showed the highest shear bond strength with 35.22 ± 4.40 MPa. OptiBondTE reached 93.8% of its control value. The self-etch system PeakSE presented significantly lower bond strength. The shear bond strength to dentin ranged between 19.15 ± 3.49 MPa for OptiBondTE and 43.94 ± 6.47 MPa for PeakSE. Etch-and-rinse systems had consistently higher bond strength to CO2 9.3 µm laser-ablated enamel. Using the maximum recommended energy for dentin ablation, the self-etch system PeakSE reached the highest bond strength (43.9 ± 6.5 MPa).

Influence of irradiation by a novel CO2 9.3-µm short-pulsed laser on sealant bond strength.

The objective of this in vitro study was to evaluate whether irradiation of enamel with a novel CO2 9.3-µm short-pulsed laser using energies that enhance caries resistance influences the shear bond strength of composite resin sealants to the irradiated enamel. Seventy bovine and 240 human enamel samples were irradiated with a 9.3-µm carbon dioxide laser (Solea, Convergent Dental, Inc., Natick, MA) with four different laser energies known to enhance caries resistance or ablate enamel (pulse duration from 3 µs at 1.6 mJ/pulse to 43 µs at 14.9 mJ/pulse with fluences between 3.3 and 30.4 J/cm2, pulse repetition rate between 4.1 and 41.3 Hz, beam diameter of 0.25 mm and 1-mm spiral pattern, and focus distance of 4-15 mm). Irradiation was performed "freehand" or using a computerized, motor-driven stage. Enamel etching was achieved with 37% phosphoric acid (Scotchbond Universal etchant, 3M ESPE, St. Paul, MN). As bonding agent, Adper Single Bond Plus was used followed by placing Z250 Filtek Supreme flowable composite resin (both 3M ESPE). After 24 h water storage, a single-plane shear bond test was performed (UltraTester, Ultradent Products, Inc., South Jordan, UT). All laser-irradiated samples showed equal or higher bond strength than non-laser-treated controls. The highest shear bond strength values were observed with the 3-µs pulse duration/0.25-mm laser pattern (mean ± SD = 31.90 ± 2.50 MPa), representing a significant 27.4% bond strength increase over the controls (25.04 ± 2.80 MPa, P ≤ 0.0001). Two other caries-preventive irradiation (3 µs/1 mm and 7 µs/0.25 mm) and one ablative pattern (23 µs/0.25 mm) achieved significantly increased bond strength compared to the controls. Bovine enamel also showed in all test groups increased shear bond strength over the controls. Computerized motor-driven stage irradiation did not show superior bond strength values over the clinically more relevant freehand irradiation. Enamel that is made caries-resistant with CO2 9.3-µm short-pulsed laser irradiation showed at least equal or significantly higher shear bond strength to pit and fissure sealants than non-laser-irradiated enamel. The risk of a sealant failure due to CO2 9.3-µm short-pulsed laser irradiation appears reduced. If additional laser ablation is required before placing a sealant, the CO2 9.3-µm enamel laser-cut showed equivalent or superior bond strength to a flowable sealant.

Treatment planning in dentistry using an electronic health record: implications for undergraduate education.

OBJECTIVE: Treatment planning, an essential component of clinical practice, has received little attention in the dental literature and there appears to be no consistent format being followed in the teaching and development of treatment plans within dental school curricula. No investigation, to our knowledge, has been carried out to explore the subject of treatment planning since the advent of electronic health record (EHR) use in dentistry. It is therefore important to examine the topic of treatment planning in the context of EHRs. METHODS: This paper reports on how 25 predoctoral dental students from two U.S. schools performed when asked to complete diagnosis and treatment planning exercises for two clinical scenarios in an EHR. Three calibrated clinical teaching faculty scored diagnosis entry, diagnosis-treatment (procedure) pairing, and sequencing of treatment according to criteria taught in their curriculum. Scores were then converted to percent correct and reported as means (with standard deviations). RESULTS: Overall, the participants earned 48.2% of the possible points. Participants at School 2 earned a mean of 54.3% compared with participants at School 1, who earned 41.9%. Students fared better selecting the appropriate treatment (59.8%) compared with choosing the correct diagnoses (41.9%) but performed least favorably when organizing the sequence of their treatment plans (41.7%). CONCLUSION: Our results highlight the need to improve the current process by which treatment planning is taught and also to consider the impact of technology on the fundamental skills of diagnosis and treatment planning within the modern educational setting.

Profilometric surface roughness analysis of christensen metal temporomandibular joint prostheses.

Functional impairment affecting the quality of life results when a wide range of both muscular and joint pathologies affect the temporomandibular joint (TMJ). Alloplastic reconstruction of joints using Christensen metal TMJ implants have been used since the 1960s for many such patients. To ensure the longevity of such TMJ prostheses, the wear rate of such implants should be minimal. Because surface roughness is an important factor that influences the wear rate, in this study we measured the surface roughness of the condylar and the fossa elements of the new and retrieved Christensen metal TMJ prostheses using the noncontacting optical interferometer (ZYGO-New View 5000). The roughness parameters of the retrieved specimens were statistically higher (p < 0.05) than those for the new specimens, but were less than the retrieved metal total knee implants as reported in the literature.