Spray coverage and pest management efficacy of a solid set canopy delivery system in high density apples.

BACKGROUND: Air blast sprayers are not optimized for spraying the short statured trees in modern apple orchards, resulting in off target drift and variable coverage. A solid set canopy delivery system (SSCDS) consisting of a microsprayer array distributed throughout the orchard was investigated as a replacement agrochemical application method in this study. SSCDS's have the potential to optimize coverage, rapidly spray applications, and remove the operator and tractor from the orchard. RESULTS: Air blast and SSCDS applications were compared using water sensitive paper, bioassays, and pest damage assessments. Pest management and coverage were compared using application volumes of 700 and 795 L ha-1 , respectively. In 2013, adaxial coverage measurements showed no difference between the treatments, but air blast sprayers had higher coverage levels on the abaxial surfaces. There were no significant differences in coverage in 2014. Bioassays using Choristoneura rosaceana fed on leaf discs treated by the SSCDS displayed 95.8% mortality in 2013 and 94.2% mortality in 2014, and air blast treated larval mortality was 95% in 2013 and 100% in 2014. Damage evaluations in both years generally showed no significant differences between the air blast plots and the SSCDS plots, but significant differences between the treated plots and untreated control. CONCLUSIONS: The prototype SSCDS was an effective pest management tool in high density apples, and offered a number of advantages over an air blast. Further engineering and research into coverage optimization would offer producers a novel tool for foliar agrochemical applications. © 2019 Society of Chemical Industry.

Effect of instruction, light curing unit, and location in the mouth on the energy delivered to simulated restorations.

PURPOSE: To determine the amount of energy (Joules/cm²) delivered by students to simulated restorations in a patient simulator based on the restoration location, the curing light unit used, and before vs. after instruction on how to improve their light curing technique. METHODS: 30 dental students "light cured" two simulated restorations (that were 1-mm deep anterior and 4-mm deep posterior) using three light-curing units (LCUs) : VALO, Bluephase G2, and Optilux 401. A MARC Patient Simulator was used to measure the irradiance (mW/cm²) received by the restorations in real-time to calculate the radiant exposure (J/cm²) delivered during a 20-second exposure. At first, students were asked to use the light curing technique that they had been previously taught. They were then given 5 minutes of additional verbal instructions and a practical demonstration on proper curing technique using the patient simulator. They then light cured the restorations again. Based on a literature review, 16 J/cm² was considered the minimum acceptable radiant exposure. RESULTS: Before receiving instruction using the simulator, some students delivered as little as 4 J/cm² to the restoration. A mixed model test determined that the radiant exposure delivered to the anterior restoration was significantly greater than that delivered to the posterior restoration (Plt; 0.001). Additionally, when the locations were compared for each LCU individually, a paired t-test determined that before the students received the additional instruction, the anterior restoration received a significantly greater radiant exposure than the posterior restoration, for all three LCUs. Further paired t-tests and Wilcoxon signed-rank tests determined that after instruction, the radiant exposure improved significantly at both the anterior and posterior locations, for all three LCUs. The Bluephase G2 and the VALO each individually delivered 45% more radiant exposure than the Optilux 401 (P< 0.001 for both). The Bluephase G2 and VALO lights delivered similar mean radiant exposures (25.4 J/cm² and 25.7 J/cm², respectively). This difference was not significant. Depending on the light unit used, at the posterior location, there was a 24 to a 52% increase in the mean radiant exposure that was delivered after instruction compared to before instruction. CLINICAL SIGNIFICANCE: Prior to using the patient simulator, students and their instructors thought that the students were delivering an adequate amount of energy when light curing. This was not always the case. The location of the restoration, the curing light output, its size and shape and how it is used all affected the amount of energy delivered to a restoration. Dental professionals and educators should be aware that appropriate training can improve the amount of energy delivered, and that restorations in posterior teeth will require longer exposure times than those in anterior teeth.

Clinical Significance of Bis-GMA and HEMA Orthodontic Resins Bonding to Enamel and Ceramic Materials.

The advancement of new ceramic materials for dental crowns has prompted the need for improved methods of bonding orthodontic brackets to these surfaces. Currently, lithium-disilicate is the primary material being used for anterior crowns, while zirconia is the primary material being used in the posterior. The purpose of this study was to compare the shear bond strength of HEMA (Assure® Universal Bonding Resin) and bis-GMA (Assure® PLUS All Surface Bonding Resin) orthodontic bonding resins on enamel, lithium-disilicate, and zirconia materials. Two groups were formed, with three tested surfaces per group (n = 20). The categories included premolars, zirconia rods, and lithium-disilicate rods. Group 1 was treated with Assure, and group 2 was treated with Assure PLUS. Zirconia rods (1 cm x 1 cm x 4 cm) were used to represent zirconia crowns, and IPS e.max CAD rods (1 cm x 1 cm x 2 cm) were used to represent lithium-disilicate crowns. Assure and Assure PLUS bonding agents were applied according to the manufacturer's specifications, and standard edgewise universal premolar brackets were secured using Light Bond™ paste without fluoride. After 24 hours the brackets were sheared with a universal testing machine (Instron® 5566A) and the results were recorded. Data were analyzed using a combination of ANOVA and Tukey tests. A P value of less than .05 was considered statistically significant. Although group 1 and group 2 gave statistically equivalent results, the authors found that the ease of use when applying the group 2 bonding agent made it a safer, superior product within the confines of this study. It did not require a 4-minute hydrofluoric acid-etch and needed half the curing time of the group 1 agent when bonding to ceramic materials.

Key Value Considerations for Consultant Pharmacists.

Managing the efficiency and costs of residents' drug regimens outside the acute-care hospital and through transitions of care requires a toolbox filled with cost-control tools and careful collaboration among the pharmacy provider(s), facility staff, and the consultant/senior care pharmacist. This article will provide the reader with key long-term care business strategies that affect the profitability of the pharmacy provider in various care settings while, at the same time, ensuring optimal therapy for residents as they transition across levels of care. Readers can take away ideas on how to access critical information, what they can do with this information, and how they can improve the overall care process. Four experts in various aspects of pharmacy management share their insights on pharmacy practice issues including formulary management, performance metrics, short-cycle dispensing challenges/solutions, cost-control measures, facility surveys, billing practices, medication reconciliation, prospective medication reviews, and transitions of care.

Effect of curing light and restoration location on energy delivered.

This study determined how long it would take skilled operators to deliver 16 J/cm2 to an anterior or a posterior restoration using different light-curing units (LCUs). Three skilled operators used the following LCUs at two locations in the MARC-patient simulator: Optilux 501 standard mode for 20 s; Sapphire Supreme for 5 s; Elipar™ S10 for 5 s and 20 s; Demi™ Plus standard mode for 5 s; SmartLite® Max boost mode for 5 s and continuous mode for 20 s; Radii Plus for 30 s; Valo (main version) in standard mode for 20 s and Xtra Power mode for 3 s; and Valo Cordless in standard mode for 20 s and Xtra Power mode for 3 s. The three MARCtrained operators made 30 readings with each light over 7 days. The energy (J/cm2) delivered to the anterior Class III and posterior Class I simulated restorations in MARC was recorded using a laboratory-grade spectroradiometer, and the time each light would take to deliver 16 J/cm2 calculated. ANOVA and Fisher's PLSD tests compared differences in the time to deliver 16 J/cm2 of energy, α = 0.05. Three-way ANOVA showed there was no significant difference between the operators, but there was a difference between the lights and locations. The Valo main and Valo Cordless in the Xtra Power mode delivered 16 J/cm2 in the shortest time at both locations. The Radii Plus took the longest to deliver 16 J/cm2, taking twice as long in the posterior location.

Thermal effects on pulp due to laser and handpiece usage.

OBJECTIVE: The study was designed to compare changes in pulpal temperature during ablation of dental hard tissue while using two established erbium dental laser systems, a new CO2 laser system, and a conventional high-speed handpiece. METHODS: Eighty non-carious human extracted molars were separated into four sample groups of 20 teeth each. Three laser systems were used, respectively, to ablate the occlusal surface of the teeth in three of the groups for 60 seconds each. The high-speed handpiece was used to drill the occlusal surface of the fourth group for 60 seconds. Pulpal temperatures were measured using thermocouples inserted into each tooth's pulpal chamber prior to ablation. RESULTS: None of the average temperature increases approached the threshold of 5.5°C at which pulpal damage begins. On average, the pulpal temperature of teeth ablated with the Waterlase MD system increased the most (3.56°C). The traditional handpiece caused the lowest average temperature increase (1.57°C), followed by the LightWalker DT system (3.20°C) and the Solea CO2 system (3.30°C).

Comparative performance of two whitening systems in a dental practice.

OBJECTIVE: A randomized, controlled clinical trial was conducted to compare the safety and whitening efficacy of high-adhesion tooth-whitening strips with a marketed in-office professional tooth-whitening system. METHODS AND MATERIALS: This open-label study was conducted in a private dental practice, and adult volunteers were assigned (2:1) to either 9.5 percent hydrogen-peroxide whitening strips (Strip group) or an in-office light plus 25 percent hydrogen-peroxide whitening gel treatment (In-office group). The Strip group was instructed to treat the maxillary arch once daily for 30 minutes over a 20-day period, while the In-office group underwent professional application of light plus whitening gel in a single office visit. Whitening response was measured as change in yellowness (b*) and lightness (L*) at Day 21 using standardized digital images of the maxillary anterior teeth, while safety was assessed as tooth sensitivity and oral irritation occurrence. A total of 45 subjects enrolled, were randomized, and received treatment; 44 completed the study. RESULTS: At Day 21, significant improvement in b* and L* was noted in both groups (P≤0.001). The adjusted mean (SE) ΔL* in the Strip group (1.72 (0.104)) was significantly greater than that in the In-office group (1.17 (0.153)) (P = 0.005). Both test products were well tolerated. Overall, both the strip and in-office treatments resulted in significant tooth whitening.

Comparison of the effect of two interdental cleaning devices around implants on the reduction of bleeding: a 30-day randomized clinical trial.

OBJECTIVE: To determine the effectiveness of a water flosser in reducing the bleeding on probing (BOP) index around dental implants as compared to flossing. METHODS AND MATERIALS: Patients with implants were randomly assigned to one of two groups in this examiner-masked, single-center study. The study compared the efficacy of a manual toothbrush paired with either traditional string floss or a water flosser. RESULTS: The primary outcome was the reduction in the incidence of BOP after 30 days. There were no differences in the percent of bleeding sites between the groups at baseline. At 30 days, 18 of the 22 (81.8%) implants in the water flosser group showed a reduction in BOP compared to 6 of the 18 (33.3%) in the floss group (P=0.0018). CONCLUSIONS: These results demonstrate that the water flosser group had statistically significantly greater bleeding reduction than the string floss group. The authors concluded that water flossing may be a useful adjuvant for implant hygiene maintenance.

Two-year evaluation indicates zirconia bridges acceptable alternative to PFMs.

OBJECTIVE: The aim of this in-vivo study was to evaluate the 2-year clinical performance of zirconia computer-aided design/computer-aided manufacturing (CAD/CAM)-generated bridges. METHODS: A total of 16 three- or four-unit Lava zirconia bridges were done on 15 subjects. The bridges were cemented using RelyX™ Unicem Self-Adhesive Universal Resin Cement. Evaluation was done at 6-month, 1-year, and 2-year recall visits. Evaluation criteria were color stability and matching, marginal integrity, marginal discoloration, incidence of caries, changes in restoration-tooth interface, changes in surface texture, postoperative sensitivity, maintenance of periodontal health, changes in proximal and opposing teeth, and maintenance of anatomic form. In each of these parameters, the bridges were rated in one of three possible categories: "A" (alpha)--ideal; "B" (bravo)--acceptable; and "C" (charlie)--unacceptable. RESULTS: After 2 years, 100% of the bridges were rated "A" for color stability and matching, marginal discoloration, incidence of caries, changes in restoration-tooth interface, changes in surface texture, postoperative sensitivity, and change in proximal or opposing teeth. In the parameter of marginal integrity, 6.25% of the bridges were rated "B;" the remaining 93.75% were rated "A." Maintenance of periodontal health was rated "B" for 6.25% of the bridges and "A" for 93.75%. At 2 years, 12.5% of the bridges rated "C" in maintenance of anatomic form and 87.5% rated "A." CONCLUSION: The overall clinical outcome was that the CAD/CAM-generated zirconia bridges were clinically acceptable.

Impact of pen utilization on insulin cost reduction in long-term care facilities.

OBJECTIVE: To determine the impact on insulin acquisition cost of a pharmacy program to convert insulin utilization from multidose vials to pen-delivery systems for long-term care residents covered by Medicare Part A, and managed care plans. DESIGN: Retrospective cost comparison. SETTING: Long-term care facilities. PATIENTS: Residents covered by Medicare Part A and managed care plans. INTERVENTIONS: Policy to replace insulin vials with pen devices, effective July 2009. MAIN OUTCOME MEASURES: Mean insulin cost-per-patient day (total insulin purchases divided by patient admission days) and pen utilization (pen purchases as a percent of total insulin purchases). RESULTS: Insulin purchase data covered 2,405 admissions in 75 facilities over the 12-month period ending June 2010. Pen device purchases increased from less than 1% to almost 35% of total insulin purchases over the study period during which insulin cost per patient-day declined from $10.29 to $4.08. For Medicare Part A patients with admissions of 30 days or fewer, the most frequent visit type, mean cost per patient-day decreased from $13.73 to $9.19 as pen purchases increased from less than 1% to about 32%. For these same patients, mean cost per patient-day for admissions using only pen devices was $7.04, compared with $11.79 for admissions using only vials (P < 0.001). Significant differences in mean cost per patient-day were also found for residents covered by managed care and for longer admissions. CONCLUSION: Total insulin costs can be reduced through higher utilization of pen devices by patients in long-term care facilities.

Provisional materials: key components of interim fixed restorations.

Clinicians have many choices of provisional materials from which to choose when fabricating interim fixed restorations. While traditional materials are still in use today, temporary materials are continuously being updated and improved upon. In addition to the functional necessities required of the provisional material, it must also provide esthetic value for the patient. This article provides an overview of provisional materials, including newer bis-acryls that have helped eliminate some of the challenges associated with traditional acrylic materials. Composite resin preformed crowns for single-unit provisional applications are also discussed, along with CAD/CAM-fabricated materials. Regardless of the material selected, a provisional restoration must maintain and protect the underlying tooth structure from ill effects.

The protective action decision model: theoretical modifications and additional evidence.

The Protective Action Decision Model (PADM) is a multistage model that is based on findings from research on people's responses to environmental hazards and disasters. The PADM integrates the processing of information derived from social and environmental cues with messages that social sources transmit through communication channels to those at risk. The PADM identifies three critical predecision processes (reception, attention, and comprehension of warnings or exposure, attention, and interpretation of environmental/social cues)--that precede all further processing. The revised model identifies three core perceptions--threat perceptions, protective action perceptions, and stakeholder perceptions--that form the basis for decisions about how to respond to an imminent or long-term threat. The outcome of the protective action decision-making process, together with situational facilitators and impediments, produces a behavioral response. In addition to describing the revised model and the research on which it is based, this article describes three applications (development of risk communication programs, evacuation modeling, and adoption of long-term hazard adjustments) and identifies some of the research needed to address unresolved issues.

Hospital planning for weapons of mass destruction incidents.

As terrorist attacks increase in fre-quency, hospital disaster plans need to be scrutinized to ensure that they take into account issues unique to weapons of mass destruction. This paper reports a review of the literature addressing hospital experiences with such incidents and the planning lessons thus learned. Construction of hos-pital disaster plans is examined as an ongoing process guided by the disaster planning committee. A review is completed of six special elements of weapons of mass destruction incidents that should be addressed in hospital disaster plans. The paper closes with a dis-cussion of the importance of train-ing and exercises in maintaining and improving the disaster plan.

Investigation of a new approach to measuring contact angles for hydrophilic impression materials.

PURPOSE: The purpose of this investigation was to examine the initial water contact angles of seven unset impression materials using commercially available equipment, in an effort to determine whether polyether impression materials (Impregum) have lower contact angles and are, therefore, more hydrophilic than VPS impression materials. MATERIALS AND METHODS: The hydrophilic properties of unset polyether and VPS impression materials were analyzed with respect to their water contact angle measurements using the commercially available Drop Shape Analysis System DSA 10. Twenty-five data points per second were collected via video analysis. There was no delay from start of measurement and data collection. Data was collected for approximately 12 s. Droplet size was determined on the thickness of canula. If the droplets became too small in volume, the water that evaporated during the measurement was large in comparison to the volume of the droplet. Therefore, 5 microl was chosen as the lowest volume. Five trials were conducted per series for each featured material. Contact angles were calculated using the circle fitting method. Three tests using this technique were designed to control the variables of contact angle measurement with regard to time, the varying amount of fluid in contact with impression material during clinical use, and material thickness. Sample thickness of impression material was controlled by stripping the paste flat on a glass plate using a marking template to ensure a constant film thickness. Tests were conducted in a climatized room at 24 degrees C +/- 1 degree C. Deionized water was used as the fluid. The device was calibrated according to manufacturer's instruction for Young-Laplace fitting prior to the measurements. Results were analyzed using One-Way ANOVA, Tukey test, and t-test, as appropriate. RESULTS: Comparing the fast setting impression materials by One-Way ANOVA and Tukey tests (p < .05) revealed the initial contact angles to range from 66.2 +/- 1.5 degrees to 127.5 +/- 4.4 degrees , of which the polyether material was the lowest after 45 s (66.2 +/- 1.5 degrees ), 120 s (70.3 +/- 2.8 degrees ), and 24 h (80.3 +/- 1.0 degrees ) after start of the mix. The selected times represent the different stages of unset material, ranging from 45 s as the earliest practical data collection time to 24 h, at which a stone model would be poured. The polyether materials tested exhibited lower contact angles and, thus, significantly higher initial hydrophilicity than all measured VPS materials. Additionally, Impregum impression materials are more hydrophilic in the unset stage than in the set stage. VPS may show a stepwise development of hydrophilicity in the set stage that was not observed in the unset stage. CONCLUSIONS: The polyether impression materials tested were significantly more hydrophilic before, during, and after setting than that of VPS impression materials. Regardless of the amount of water in contact with the impression material, the polyether impression materials showed a significantly higher hydrophilicity in the unset stage than the VPS materials. The initial contact angle was not dependent on the thickness of the material. All parameters, including variation of time, volume of water droplet, and thickness of material, resulted in different absolute contact angles, but did not lead to a dramatic change in the ranking of the materials with regard to their hydrophilic behavior.

Clinical evaluation of total-etch and self-etch bonding systems for preventing sensitivity in Class 1 and Class 2 restorations.

The author conducted an in vivo investigation to compare the clinical performance of 4 commercial bonding agents on postoperative sensitivity. Restorations in this study were limited to Class I and Class II lesions. The patient pool consisted of 36 patients and 72 teeth (2 teeth per patient) with either a Class I or Class II lesion > 1 mm in depth present in both teeth. The 4 adhesives tested in this study were distributed among patients as follows: on the first tooth, 12 patients received an application of adhesive 1, 12 received adhesive 2, and 12 received adhesive 3. All 36 patients received an application of adhesive 4 on the second tooth. All lesions were restored using a submicron particle hybrid composite. One-day and 1-week recall evaluations to measure sensitivity were taken by administrative staff in-office and by telephone. An independent clinician assessed the 1-month recall of each patient with the patient present in a clinical setting. No statistically significant differences were seen among the groups at any recall interval; however, the fourth adhesive performed consistently better than the other 3 at all intervals. All 4 bonding agents performed with clinically acceptable outcomes after a 30-day period. Certain lesion, tooth, and patient characteristics may predispose restorations to sensitivity.

Applicable research in practice: understanding the hydrophilic and flow property measurements of impression materials.

The flow properties and hydrophilicity of an impression material are key factors that affect its performance. This article details in vitro studies comparing these properties in 1 polyether and several vinyl polysiloxane light-body impression materials. The first series of studies examined the materials' flow properties used in a "shark fin" measurement procedure to determine which exhibited superior flow characteristics. The second series of studies reviewed the hydrophilic properties of the materials. Video analysis was used to record contact angle measurements at the early- and late-stage working times. Results showed 1 polyether material to be more hydrophilic. Applying this knowledge to practice, the authors present a clinical case in which a polyether's superior flow and quality of detail were used to make impressions for a patient receiving 8 single-unit zirconia crowns.

Comparison of temperature changes in the pulp chamber induced by various light curing units, in vitro.

This study compared the temperature increase in a pulp chamber as a result of using various light-curing units during resin composite polymerization, and it determined the effect of remaining dentin thickness on temperature rise. A Class II occlusodistal cavity with a remaining dentin thickness of 2 mm was prepared in an extracted human mandibular molar. A 2-mm layer of fine hybrid resin composite was placed on the floor of the proximal box. A K-type thermocouple was inserted into pulp chambers filled with heat sink compound, and pulp chamber temperature rise (starting temperature: 37.0 +/- 0.1 degrees C) during polymerization of the composite was measured. The light-curing units tested included two halogen lights, Spectrum 800 and Elipar Trilight (Standard and Exponential mode); a light-emitting diode (LED, Elipar Freelight) and a plasma arc (Virtuoso, Xenon Power Arc). Irradiation time was 40 seconds for the halogen and LED lights and 3 seconds for the plasma arc light. Five measurements were carried out for every light-curing unit. The same experimental design was conducted after the cavity preparation was modified, leaving a 1-mm thick dentin layer. The Kruskal-Wallis and multiple comparison tests were used to evaluate the differences among the tested curing units. Mann Whitney-U tests were used to compare the mean temperature rise in each curing unit for different remaining dentin thicknesses. The increase in pulp chamber temperature ranged between 1.40-3.8 degrees C. The highest temperature rise was observed when using Elipar Trilight Standard mode, and the lowest temperature rise was observed with light emitting diode for both remaining dentin thicknesses. The only significant differences in temperature rise were observed between Elipar Trilight Standard mode and LED. No significant difference (p > 0.01) existed for the different modes of Elipar Trilight. A statistically significant higher temperature rise was observed within each curing unit at a depth of 1 mm compared to 2 mm. Although the tested light-curing units caused a temperature rise in the pulp chamber, none exceed the critical value of 5.5 degrees C.

Restoring anterior maxillary dentition using alumina- and zirconia-based CAD/CAM restorations.

Despite proven strength, durability, and improved esthetics, ceramometal restorations have not consistently enabled the most esthetic, lifelike reproduction of natural dentition. Also, inherent weaknesses in many metal-free materials have precluded their use in the high stress-bearing posterior region. Therefore, as a result of the need for esthetic and durable all-ceramic restorations, manufacturers have introduced ceramics with an increased alumina or zirconia content that are recommended for placement anywhere in the mouth for single units and as far back as the first premolar.