Three-way Syringe Research Articles

Microbial Contamination of Dental Unit Waterlines among Dental Clinics of India- An In vitro Study.

Dental Unit Water Line (DUWL) deliver water to different handpieces in a dental unit. The water in DUWL circulates in a closed system, where it is taken from a container. The quality of dental water is of considerable importance since patients and dental staff are regularly exposed to water and aerosols generated from dental equipment. Output water from DUWLs may be a potential source of infection for both dental health care personnel and patients. To assess the microbial contamination in the DUWL among dental clinics in Chennai. An in vitro study was conducted on 60 water samples from 20 dental clinics in Chennai in December 2019. Water samples were collected from three different sources of the Dental unit according to ADA guidelines. The collected samples were assessed for the presence of Aspergillus, Acinetobacter, Pseudomonas aeruginosa, and Legionella by agar plate method. The data were analysed using SPSS software version 20. Legionella was the most prevalent microorganism with 70% prevalence in a three-way syringe and 50% in scaler and airotor, followed by Pseudomonas aeruginosa and Acinetobacter with 10% prevalence in scaler and airotor and Aspergillus with a prevalence of 10% in the three-way syringe. Most of the dental units were contaminated with Aspergillus, Legionella, Pseudomonas aeruginosa and Acinetobacter which pose a serious threat to the patients as well as the dentists.

Assessment of Prevalent Gingival Shades in the South Indian Population: An Observational Study.

Gingival shade matching, often overlooked, plays an integral role in designing prostheses for patients with high smile lines, gingival defects, and cases where the acrylic flange of removable dentures extends into the aesthetic zone.The purpose of this study was to find the most prevalent gingival shade in a sample of the South Indian population. A total of 110 participants were included in the study based on the inclusion and exclusion criteria. The standard daylight method of shade matching was used for this study. The participants were seated in a dental chair in the vertical position with their heads supported, their mouths open, and cheek retractors in place. The study area, gingiva, and vestibular region in relation to maxillary and mandibular right central incisors were dried with a three-way syringe, 15cm away, for 3 seconds before shade matching for 5 seconds at each reference point with an Ivoclar Vivadent IPS Dsign shade guide. The most prevalent shade in the marginal and vestibular regions of the gingiva of the South Indian population was found to be GM2 shade, while the most prevalent shade of the attached gingiva was found to be G2 shade. A good percentage of the attached gingival shade was not matched with the tabs available in this shade guide.

Effectiveness of a Single Chair Side Application of NovaMin® [Calcium Sodium Phosphosilicate] in the Treatment of Dentine Hypersensitivity following Ultrasonic Scaling-A Randomized Controlled Trial.

Dentinal hypersensitivity or cervical dentinal sensitivity is one of the commonest clinical problems. The aim of this randomized controlled trial was to evaluate the effectiveness of a single chair side application of 100% pure calcium sodium phosphosilicate (NovaMin®) in reducing dentin hypersensitivity following ultrasonic scaling as evaluated on a visual analogue scale (VAS). The study included 50 subjects who were selected based on an evaluation of dentinal hypersensitivity on a VAS carried out using a metered air blast from a three-way syringe and divided into two groups (n = 25/group); i.e., the test group (Group A) received the NovaMin® paste and the control group (Group B) received a placebo paste made from pumice. All the 50 subjects included in the study were had VAS scores of 3 or more. The NovaMin® powder mixed with distilled water was applied. Dentinal hypersensitivity was reassessed immediately and after 1, 2 and 4 weeks after the procedure. Results showed that the percentage reduction of dentinal hypersensitivity following a single application of NovaMin® in powder form was about 76.38% immediately, 67.72% one week postoperatively, 52.76% two weeks postoperatively and 26.78% four weeks postoperatively. It can be concluded from the results of the current clinical study demonstrated that a single chair side application of NovaMin® in powder form has a significant and immediate reduction in dentinal hypersensitivity, which lasted nearly for four weeks.

Subcutaneous Emphysema of Dental Origin – Two Case Reports with a Comprehensive Review of Literature from 1965 to 2020, with an Emphasis on Timely Management

Subcutaneous emphysema (SE) is a rare but possible complication of dental treatment resulting from the usage of high-speed air-driven instruments and introduction of irrigating solutions like hydrogen peroxide into soft tissues. Two case reports are described here, namely (a) drying of root canals using a three-way syringe by “Venturi” technique and (b) accidental injection of hydrogen peroxide instead of local anesthesia in an infiltration technique. A review of the literature is done wherein a search for terms such as pneumomediastinum, mediastinitis, embolism, or extensive SE (ESC) from 1965 to 2020 using the PubMed search engine was done and the results were tabulated. Since the number of cases and complications reported are on the rise, data regarding diagnosis, investigations, and a management protocol with an emphasis on prevention have been elaborated. Methods such as reductive manipulation or “counter incision,” as incited from medical literature, have been suggested to reduce morbidity and mortality. In both of the case reports, subcutaneous cervicofacial emphysema resolved briefly due to the effectual reduction maneuver implemented promptly.

Orthodontic bond strength with the use of non-aerosol producing bonding primers in lieu of conventional primers: An in vitro evaluation.

To evaluate the efficacy of non-aerosol producing restorative self-etching primers (SEPs) as a substitute for conventional orthodontic bonding primers and to analyze the extent of residual composite on the tooth post-debonding. Eighty-four extracted human premolars were randomly divided into seven groups based on the adhesive and the bonding protocol used. The study comprised Prime and Bond one select (Dentsply), G-Premio Bond (GC), which were each divided into three subgroups based on the method used for moisture control and the control group (Transbond XT conventional total etch). The three methods for moisture control in study groups were: without drying, air-drying with the use of a three-way syringe, and with the use of blotting paper. Shear bond strength (SBS) was tested using a universal testing machine (UTM), and after debonding, the enamel surface of each tooth was examined under 10× magnification to evaluate adhesive remaining index (ARI) scores. Groups 2A (Prime and Bond; without drying) & 1 (Transbond XT) had the lowest and highest SBS values, respectively (P = 0.001). Comparison of ARI between the control group and group 2b (Prime and Bond; air-drying with 3 in 1) showed a significant difference (P = 0.041). Comparison of ARI between control group and group 2c (Prime and Bond; blotting paper) showed a significant difference (P = 0.017). Rest all other comparisons were non-significant. Transbond XT had SBS values higher than the self-etch groups. Among the self-etch groups, G-Premio Bond had higher SBS values when the traditional methods of air-drying were followed. Use of blotting paper for drying that produced variable SBS values can be an effective alternative method. G-Premio Bond with its adequate bond strength under manufacturer's instruction seems promising in this regard.

Influence of Liquid on the Tooth Surface on the Accuracy of Intraoral Scanners: An In Vitro Study.

To assess the influence of liquid attached on the tooth surfaces on the accuracy (trueness and precision) of intraoral scanners and the effectiveness of the drying method (using compression air) to exclude the influence of liquid on the scanning results. A mandibular jaw model was scanned using an industrial computed tomography scanner to obtain a reference model. A scanning platform was designed to simulate three specific tooth surface states (dry, wet, blow-dry). Two kinds of liquids (ultra-pure water and artificial saliva) were used for the test. Two intraoral scanners (Trios 3 and Primescan) were used to scan the mandibular jaw model 10 times under each condition. All scanning data were processed and analyzed using dedicated software (Geomagic Control 2015). Trueness and precision comparison were conducted within the 12 groups of 3D models divided based on different intraoral scanners and liquids used under each condition. The root mean square (RMS) value was used to indicate the difference between the aligned virtual models. The color maps were used to evaluate and observe the deviation distribution patterns. The 3-way ANOVA (condition, intraoral scanner, liquid) followed by the Tukey test were used to assess precision and trueness. The level of significance was set at 0.05. The mean RMS values obtained from wet condition were significantly higher than those of the dry and blow-dry condition (p < 0.001, F = 64.033 for trueness and F = 54.866 for precision), which indicates less accurate trueness and precision for wet condition. For two different types of liquids, the mean RMS value was not significantly different on trueness and precision. The deviations caused by liquid were positive and mainly distributed in the pits and fissures of the occlusal surface of posterior teeth, the interproximal area of the teeth, and the margin of the abutments. Liquid on the tooth surface could affect intraoral scanning accuracy. Blow-drying with a three-way syringe can reduce scanning errors.

Effect of Inhibition of Bacterial Proliferation by Neutral Electrolytic Water inDental Unit Waterlines

Background: Microbial contamination in dental unit waterlines (DUWLs) has recently become an important issue in the field of dental infection control. Using neutral electrolytic water as a new disinfecting method has attracted considerable attention. However, long term data about the effect of using neutral electrolytic water in clinical settings are scarce. This is the first study to evaluate the long term effectiveness of inhibition of bacterial proliferation using the purification system to supply neutral electrolytic water to refine the waterworks in DUWLs. Methods: Before the study, we investigated the actual levels of bacterial contamination in DUWLs. Then we did thorough cleaning of DUWLs and water samples were collected 6 dental units. Three dental units assigned as Group A had purification systems that used neutral electrolytic water, and the other 3 units were the Control group. Water samples were collected from the gargle water, high-speed handpieces and the three-way syringe. We utilized the equipment in Group A, and both groups were maintained for daily clinic work for 14 months. We counted the bacterial colony forming units (cfu) for each sample and identified the pathogenic bacterial species. Results: 3 and 14 months later, no microbes were detected during the study period in Group A whereas numbers of cfu which grew from the Control group increased and glucose non-fermenting gram-negative rod of possible pathogenic organisms to human were identified in the control groups. Conclusions: The water purification system using neutral electrolytic water was effective to control the proliferation of bacteria and could maintain a hygienic environment in DUWLs.

Improving High Viscosity Extrusion of Microcrystals for Time-resolved Serial Femtosecond Crystallography at X-ray Lasers.

High-viscosity micro-extrusion injectors have dramatically reduced sample consumption in serial femtosecond crystallographic experiments (SFX) at X-ray free electron lasers (XFELs). A series of experiments using the light-driven proton pump bacteriorhodopsin have further established these injectors as a preferred option to deliver crystals for time-resolved serial femtosecond crystallography (TR-SFX) to resolve structural changes of proteins after photoactivation. To obtain multiple structural snapshots of high quality, it is essential to collect large amounts of data and ensure clearance of crystals between every pump laser pulse. Here, we describe in detail how we optimized the extrusion of bacteriorhodopsin microcrystals for our recent TR-SFX experiments at the Linac Coherent Light Source (LCLS). The goal of the method is to optimize extrusion for a stable and continuous flow while maintaining a high density of crystals to increase the rate at which data can be collected in a TR-SFX experiment. We achieve this goal by preparing lipidic cubic phase with a homogenous distribution of crystals using a novel three-way syringe coupling device followed by adjusting the sample composition based on measurements of the extrusion stability taken with a high-speed camera setup. The methodology can be adapted to optimize the flow of other microcrystals. The setup will be available for users of the new Swiss Free Electron Laser facility.

Use of confocal microscopy for quantification of plastic remnants on rough titanium after instrumentation and evaluation of efficacy of removal.

Many experts have proposed the treatment of titanium surfaces with plastic or nonmetal tips to prevent damage to implant surfaces by metal instruments during professional cleaning. It is also known that any material that is softer than titanium may leave remnants of itself on the treated surface. The aim of this study was to quantify the surface area covered by plastic remnants after instrumentation with various plastic instruments and to evaluate the efficacy of the removal of these remnants by confocal microscopy. Twenty-seven rough-surfaced titanium disks were used for quantification of plastic remnants. Nine disks each were cleaned with (1) a plastic tip on ultrasonic scaler A, (2) a carbon tip on ultrasonic scaler B, or (3) a plastic curette. Three disks from each group were cleaned with a three-way syringe for 10 seconds, and three other disks were cleaned with 0.2% chlorhexidine-soaked cotton pellets. Images were obtained at random areas on each disk with a confocal microscope, and a digital image analysis program was used to quantify the area with autofluorescence. Approximately 10% to 20% of the surface was covered with plastic remnants of the instrument, irrespective of the instrument used. These remnants were not removed with a three-way syringe or chlorhexidine-soaked cotton pellets. Plastic remnants remained after instrumentation, regardless of the instrument used. Moreover, the study highlighted the difficulty of removing all remnants with water spray or a chlorhexidine-soaked cotton pellet. This study suggests that confocal microscopy is a reproducible method for quantification that may be applied for future comparisons of methods to remove plastic residue. Further research is warranted to evaluate the biologic effects of plastic remnants.

Microbial diversity in dental unit waterlines.

Dental health care providers and patients are exposed during ongoing work to contamination by the water used in the dental units, due to accidental swallowing or aspiration of the sprays generated by the high-speed handpiece and the threeway syringe. This study evaluated the quality of water in dental units in the public dental care system of Maceio, Alagoas, Brazil, by conducting analyses of contamination by total coliforms, E.Coli, heterotrophic bacteria and filamentous fungi. We collected 200 mL of water at 5 sites in 6 dental offices of the Department of Health located in different parts of the city. A total 212 isolates and 16 genera of filamentous fungi were identified in the water collected from the dental units. Total coliforms indicated that the water used in dental units was not appropriate for human consumption. The high levels of contamination found in this study showed that water was a potential source of cross-infection.

ラバーダム装着から除去後に至るまでのＮｄ：ＹＡＧレーザーによる疼痛緩和効果に関する経時的変化

The purpose of this study was to compare the pain-relieving effects of pulsed Nd:YAG laser irradiation with topical anesthetic application during placement of a rubber dam clamp.Twenty-two students, aged 22 to 31 years (mean 24.05), who had not experienced either endodontic or cervical restorative treatment of first permanent molars, participated in this study. In this study, the same tooth for the same patient was tested three times every week. The following were the conditions of each site: 1) control site: no pretreatment before placement of the rubber dam clamp, 2) topical anesthetic site: application of topical anesthetic 60 seconds before placement of the rubber dam clamp and wash-out by three-way syringe water, 3) Nd:YAG laser irradiation site: Nd:YAG laser irradiation before placement of the rubber dam clamp. The irradiation conditions were 120 mJ, 1.2 W, 10 pps, and irradiation time was 30 sec twice. The efficacy of pain-relief was assessed by visual analogue scale (VAS) at the start, before placement of the rubber dam clamp, after placement of the rubber dam clamp, and until 20 minutes at 2-minute intervals. The clamp was removed 14 minutes after the start. Pain-relieving effects were also examined by questionnaire.The VAS levels of both placement and removal of the rubber dam clamp were high for all sites. On placement of the rubber dam clamp, the VAS level with Nd:YAG laser irradiation was statistically significantly lower than with no preparation (P<0.05: Wilcoxon signed-ranks test). During placement of the rubber dam clamp, the VAS level with Nd:YAG laser irradiation and topical anesthetic application were statistically significantly lower than with no preparation (P<0.05: Wilcoxon signed-ranks test).

INFLUENCE OF SELF‐ETCHING PRIMER DRYING TIME ON ENAMEL BOND STRENGTH OF RESIN COMPOSITES

ABSTRACT Objective: The purpose of this study was to evaluate the effects of self‐etching primer drying times on the bond strength of resin to bovine enamel. Materials and Methods: Three self‐etching primer adhesive systems–Imperva Fluoro Bond® (Shofu Inc., Kyoto, Japan), Clearfil® Liner Bond (Kuraray Co. Ltd., Osaka, Japan), and Mac Bond® II (Tokuyama Corp., Tokyo, Japan)– were used in this study, The labial enamel surfaces of bovine incisors were exposed by grinding with 240‐grit and 600‐grit wet silicon carbide paper. The primers were applied to enamel surfaces as per manufacturers' instructions. After priming, the surfaces were dried with compressed air for 0, 2, 5, 10, 20, or 30 seconds from 10 cm above the surface using a three‐way syringe. Following the application of adhesive resin, resin composites were applied into molds (diameter = 4 mm, depth = 2 mm) and were light‐cured. The shear test was performed at a crosshead speed of 1.0 mm/min. The ultrastructure of resin‐enamel interfaces was observed with SEM at magnifications of 2,000× to 3,500×. Results: Mean enamel bond strengths varied with the different drying times and ranged from 8.2 to 17.4 MPa for Clearfil Liner Bond, from 10.9 to 16.3 MPa for Imperva Fluoro Bond, and from 17.5 to 19.4 MPa for Mac Bond. For Clearfil Liner Bond and Imperva Fluoro Bond, mean bond strengths increased significantly at the 10‐second drying time, whereas Mac Bond did not experience a significant change in bond strengths. SEM examination revealed morphologic differences among the groups with varying drying times. Resin tag penetration was not clearly seen at the 0‐second drying time, but resin tags appeared to be intimately adapted to the enamel surface in specimens at the 30‐second drying time. Conclusions: The drying time of the self‐etching primer prior to the application of bonding resin affected the shear bond strength of resin to enamel for two self‐etch adhesive systems.

Influence of self-etching primer drying time on enamel bond strength of resin composites

Objectives: In clinical situations, a dentine primer is usually applied to enamel, in addition to dentine. This study was carried out to determine the influence of the air drying time of self-etching primers on their bond strength to enamel. Methods: Three self-etching primer systems, Fluoro Bond (FB, Shofu Inc.), Liner Bond II (LB, Kuraray Co.) and Mac Bond 2 (MB, Tokuyama Co.) were employed. Bovine mandibular incisors were mounted in self-curing resin and the enamel surfaces were wet ground with number 600 SiC paper. Following primer application, the enamel surface was dried with compressed air for 0, 2, 5, 10, 20, and 30 s from 10 cm above the enamel surface using a three-way syringe. Adhesives were applied and composites were condensed into a Teflon mold (4×2 mm) placed on the enamel and light activated. Ten samples per test group were stored in 37°C water for 24 h, then shear tested at a crosshead speed of 1.0 mm min −1. One-way ANOVAs followed by Duncan tests ( p<0.05) were done. Results: The enamel bond strengths varied with the different air drying times and ranged from 8.2±3.2–17.4±3.0 MPa for LB, 10.9±2.8–16.3±3.3 MPa for FB, and 17.5±2.5–19.4±2.2 MPa for MB. For LB and FB, there appeared to be a minimum drying time of 10 s. LB was the most affected by drying time, while MB did not change. Conclusions: The data suggests that the enamel bond strengths of these bonding systems can be influenced by the drying time of the primer applied prior to bond agent application and the tendency was different among the systems studied.

Time line analysis of dental restorative procedures related to dynamic instrument location

The detailed timing and recording of the sequence of tasks for dental restorative procedures was used to evaluate the effects of the location of the hand-piece and three-way syringe on the dental team performance. Sixty-four audiovisual tapes of ten dental teams, performing complete, actual restorative procedures, were made in two dental operatories that differed only in the location of the dentist's instrument cabinet. Total treatment sessions were divided into four major divisions and expressed as a percentage of the total time: patient preparation, 14%; tooth preparation, 32%; tooth restoration, 50%; and patient release, 4%. Tooth preparation and restoration took longer with the instruments in the 8-o'clock location than with them in the 12-o'clock location. When the teams were reversed, that is, changed to the other operatory, there was an increase in tooth preparation and restoration time. Instrument transfer and use, especially for the three-way syringe, tended to take longer for the 8-o'clock location. In contrast, the dentist's idle time tended to increase working with the 12-o'clock instrument location because of differences in work loads. Time line analysis provided a means of evaluating the impact of instrument location as well as an approach to assessing individual team performance.

Comparison of the effects of two handpiece locations on dental team performance

Using audiovisual tapes of 150 actual dental treatment sessions, five dental teams working with handpieces positioned in the 8-o'clock location were compared with five dental teams working with hand pieces positioned in the 12-o'clock location. Criteria used for analysis were frequency and duration of instrument transfer, critical incidents that interfered with instrument movements, and subjective responses of the dental team members. The data showed that the handpiece transfers were faster and more frequent in the 12-o'clock location where they were done via the assistant. However, the reverse was true for transfers of the three-way syringe. Most critical incidents occurred with equal frequency and were common to both rooms, but some were related to instrument location. The subjective responses indicated that the assistant working with the 12-o'clock instrument location had many more tasks and must be more highly trained.

A THREE-WAY SYRINGE AND CANNULA.

A THREE-WAY SYRINGE AND CANNULA.