• The Journal of Korean Academy of Prosthodontics
• /
• v.52 no.3
• /
• pp.177-185
• /
• 2014

Purpose: This study is designed to investigate the various impacts of different types of scaler tips such as cooper alloy base tip and the others on the surface roughness of teeth and implant by the method which is currently in clinical use. Materials and methods: Four different types of disc shaped porcelain, titanium, zirconia, and Type III gold alloy dental materials sized 15 mm diameter, 1.5 mm thickness were used for the experiment. Plastic hand curette (Group PS), cooper alloy new tip (Group IS), and stainless steel tip (Group SS) were used as testing appliances. A total of 64 specimens were used for this study; Four specimens for each material and appliance group. Surface roughness was formed with 15 degree angle in ultrasonic scaler tip and with 45 degree angle in hand curette of instrument tip and the specimen surface with 5 mm long, one horizontal-reciprocating motion per second for 30 seconds by 40 g force. To survey the surface roughness of each specimen, a field emission scanning electron microscope, an atomic force microscope, and a surface profiler were used. (Ra, ${\mu}m$). Results: According to SEM, most increased surface roughness was observed in SS group while IS groups had minimal roughness change. Measurement by atomic force microscope presented that the surface roughness of SS group was significantly greater than those of PS, IS and control groups in the type III gold alloy group (P<.05). IS group showed lesser surface roughness changes compared to SS group in porcelain and gold alloy group (P<.05). According to surface profiler, surface roughness of SS group showed greater than those of PS, IS and control groups and IS group showed lesser than those of SS group in all specimen groups. Type III gold alloy group had large changes on surface roughness than those of porcelain, titanium, zirconia (P<.05). Conclusion: The result of this study showed that newly developed copper alloy scaler tip can cause minimal roughness impacts on the surface of implant and dental materials; therefore this may be a useful alternative for prophylaxis of implant and restored teeth.

• Journal of dental hygiene science
• /
• v.1 no.1
• /
• pp.46-52
• /
• 2001

The purpose of this study was to examine dental personnels' concern for health, their personal protection manner, and whether or not they were inoculated against hepatitis B and made an inquiry of patients about that. It's ultimately meant to serve as a basis for the preparation of an anti-infection guide for the protection of dental personnels against all sorts of infectious diseases. After a survey was conducted from March 29 through May 9, 2001, the following findings were obtained: (1) The dental personnel group that had worked for 5 to less than 7 years took health examination the most, with 71.4%, before joining the hospital, and 61.5% of those who had served for 9 years or more, the greatest percentage, took medical checkup after joining the hospital(P<0.05). (2) The largest percentage of being inoculated against the anti-B type hepatitis after employment was 71.4% of the dental personnels over 35, and 57.7% of those with 9-year or more working experiences. Therefore, their age and service term made a significant difference(P<0.05). (3) There was no significant gap in personal protection practices between the dental hygienists and nurse aids(P>0.05). But the use of safety goggles for treatment was not properly done, with just 1.48 on the basis of 3 points, whereas the use of mask was scored 2.40 and the use of gloves was scored 1.96. (4) After a narcotic was used once, the leftovers were wasted by 89.7% of the dental hygienists and 70.0% of the nurse aids. More dental hygienists wasted them(P<0.05). (5) For hand washing, antibiotic liquid soap was used by 19.3% of the dental hygienists and 10.0% of the nurse aids, which were both very low percentage. And just 37.2% of the dental hygienists utilized a disposable paper towel to dry their hands, and only 36.0% of the nurse aids used the same(P<0.05).

• The Journal of the Korea Contents Association
• /
• v.13 no.11
• /
• pp.306-312
• /
• 2013

The purpose of this study was to grasp the recognition of medical consumer over the infection in dental clinic. The study performed the questionnaire by selecting the patients visiting 3 dental clinics of Daegu area as targets and analyzed 213 question papers collected. The result revealed that the infection control, which was most important for the patients, was 'instrument disinfection' (64.3%) and it was significant in age factor(P<0.01). For the responsibility of infection control, 72.3% replied that 'dentist or dental clinic staff' should be responsible for it and it was significant in academic background factor(P<0.001). For the importance of cleaning and sanitation, 70.0% replied that 'it is very important' and it was gender(P<0.05)and the age factor.((P<0.01) The person who experienced the information about the infection control of dental clinic observed hand washing(P<0.001), replacement of suction tip(P<0.001) and replacement of teeth washing cup (P<0.01) more carefully and considered whether dentist wears protective goggle more importantly than the person who did not experience it(P<0.01). If dental clinic recognizes the evaluation of infection control notified by the Ministry of Health & Welfare and performs the infection control suitable for the eye level of general medical consumer on the basis of the study result above, it can improve the reliance of hospital as well as patient's satisfaction.

• Journal of dental hygiene science
• /
• v.10 no.4
• /
• pp.199-209
• /
• 2010

The purpose of this paper is to suggest fundamental data for finding problems and ways to improve Korean dental infection control studies through the classification of literature on dental infection control which have been conducted in Korea. The collection of literature was done via seven online database programs only for domestic literature. The date of first search was September 16-17th, 2009, and the final search was completed on December 20th, 2009. (1) From the examination of the frequency of research according to the publishing form by year, it is revealed that after 2006, dental infection control is being performed most vigorously, compared with 1980's when the studied on this area started. (2) According to the classification of research method by research design of original article among the literature, original articles were 45 studies, and the others were 20 studies. It was also found that in 45 studies of original article, there were 37 studies of survey research, and there were 8 studies which include microbiology examination. (3) On the analysis of the subject of each study, glob and mask using rate have gradually increased, and the frequency of pierced with sharp implement or needle have gradually decreased. Through this research, it can be observed roughly how the results depended on subject of each studies change. However, it may be restricted to generalize the results of this research, because there are lack of clear standard and literature evidence to assess the interrelationship between each study. Also, since there are shortage of research and studies in dental infection control, the research to examine the effects should be tried actively after the standards and precaution of dental infection control developed.

• Korean Journal of Dental Materials
• /
• v.45 no.4
• /
• pp.275-286
• /
• 2018

The purpose of this study was to evaluate the effect of needle tip design and position, and irrigant flow rate on apical pressure (AP) during root canal irrigation. Five human mandibular premolars were instrumented up to #35 (0.06 taper) using nickel-titanium rotary instruments. Three different needles according to change of needle tip design (notched, side-vented, and flat) were positioned at the point of 1, 3, and 5 mm from the apical constriction (needle tip position). For each needle tip design and position, APs were measured with varying flow rates of 0.05, 0.1, 0.2, and 0.3 ml/s. When the other conditions were controlled, AP increased with decreasing needle tip position or increasing irrigant flow rate (p<0.05). The AP of flat needle was the highest, followed by notched, side-vented needle for the same needle tip position and irrigant flow rate. The APs at needle tip position of 1 mm or with more than 0.1 ml/s flow rate were higher than central venous pressure (5.88 mmHg) for all conditions. Flat needle was not recommended for clinical use due to sharp increase of AP with changing needle tip position and irrigant flow rate. For safe and effective root canal irrigation, irrigant should be applied with the needle tip position of 3 mm and flow rate of less than 0.05 ml/s.

• Journal of Convergence for Information Technology
• /
• v.9 no.5
• /
• pp.158-164
• /
• 2019

Recently many studies to reduce the noise of dental hand piece which generate inevitably mechanical sound to offend to the ear of a patient have been spotlighted. Generally, methods of adding a sound absorbing material inside the exhaust valve, air pump of machine or automobile are widely reported as optimal way to reduce the mechanical noise. In this paper we studied a new UV laser aided manufacturing of micro-porous structure of EPP substrate and applied dental hand piece to improve the efficiency of sound absorption. A lot of micro-sized pores were fabricated with UV laser processing on the surface of sliced EPP substrate. From fundamental experiments, more high-performance of micro-porous EPP substrate has finally demonstrated for sound-absorbing structure of the micro muffler inside dental hand piece, which actually has the excellent potential to apply a lot of potable machine.

• The Journal of Korean Academy of Prosthodontics
• /
• v.52 no.3
• /
• pp.233-238
• /
• 2014

Purpose: A method detecting change of jaw or alveolar bone density may be helpful in periodontal care, implant dentistry and evaluation of bone density of whole body. Materials and methods: In this study, bone density of intraoral periapical radiography using phantom-integrated XCP is compared with that of quantitative computed tomography (QCT). Results: Bone density of intraoral periapical radiography and the one measured by QCT showed high correlation (correlation coefficient = 0.92, P<.001) in alveolar bone, and relatively high correlation (0.73, P<.001) in cancellous bone. Conclusion: This study revealed possibility of scoring of bone density by intraoral periapical radiography.

• The Journal of Korea Assosiation for Disability and Oral Health
• /
• v.7 no.1
• /
• pp.29-32
• /
• 2011

There are a lot of dental emergency situations and accidental aspiration or ingestion of a dental instrument is one of the common accidents in dental practice especially on disabied or pediatric patient with negative behavior. Most of ingested foreign bodies pass through the gastrointestinal tract spontaneously, but some of them (about 20%) need endoscopic or surgical removal. This is a case of an accident during the treatment of a 18 months male patient with caries of anterior deciduous teeth. During the treatment, the gauze was used by waterproofing instead of a rubber dam. #4 round bur (approximately 2.2cm long) which was put on the tray was cling to the gauze and the bur was fell into the patient's throat. The bur was 2.2cm long and very sharp so it could not be passed spontaneously through the pylorus, so we tried to remove the bur by esophagogastroduodenoscopy. Endoscopic removal of foreign bodies in the upper gastrointestinal tract is an effective and safe procedure.

• The Journal of the Korean dental association
• /
• v.48 no.12
• /
• pp.893-918
• /
• 2010

This article is purposed of reviewing the development history of Japanese dental devices and instrument, and their related advertisement activities during the Japanese colonized period in Korea in early 20th century. Japanese dental devices and instrument were redesigned to accommodate their ergonomic shape above the simple imitation, and it implies the excessive desires brought them frustrations. The tragic earthquake on Sep. l, 1923, medical insurance law enforcement on Jan. 1, 1927, celebration of "Cavity prevention Day" started on Jun. 4, 1928, and the attack of Manchuria and China by Japan after 1931, all of these historical incidents become the preliminary requirement for the development of dental devices. On Nov. 1, 1937, Japanese government started to control dental materials, driving the campaigns for excluding foreign products and encourging the use of local products. In 1939, Nakajima dental manufacturers used this political and social atmosphere on their advertisement as saying "Our Nakajima's products have no compromise with the short raw materials, but only commitment to our quality". Since after 1940, the price and supply have been strongly under control, and the control group was appeared to manage all of supply and distribution of raw materials, regular price system, and specifications. At last, the Japanese national power were devastated in its production and distribution capacities, and get to the frustrated period. The main advertised dental devices and instruments in Korea during the Japanese colonized period were 1) dental chair, unit and cabinet, 2) dental x-ray, 3) compressors, 4) dental needles, 5) small instrument and carryon medical(emergency) kit, 6) oral hygiene and pyorrhea alveolaris, infrared rays, sunlight lamp, ultrashort wave treatment devices, 7)crown former, electric furnace, casting machine, articulator, electric lathe, and laboratory equipments, etc.

• The Journal of Korean Academy of Prosthodontics
• /
• v.35 no.3
• /
• pp.504-516
• /
• 1997

Ultrasonic instruments transfer electrical energy to mechanical energy resulting in vibration used for various dental treatments. If we could know the effect of ultrasonic instruments on the dental cements within the cast crown, we could take care when conducting periodontal surgery and when using the ultrasonic instrument to remove cast crown, it would be much more convenient. The purpose of this study was to compare the bond strength of several dental cements according to ultrasonic instrumentation time. In this study 4 types of cements were used to cement the specimens. they were treated with ultrasonic instrumentation for 0-5 minutes and the change in bond strength were statistically compared. The results were as followed. 1. The tensile bond strength of zinc phosphate cement decreased according to the increase in time of ultrasonic instrument and showed significant difference between 0 minutes and the others and between 1 minute and 2,3,4,5 minutes (p<0.05). 2. The tensile bond strength of polycarboxylate cement decreased according to the increase in time of ultrasonic instrument and showed significant difference between 5 minutes and the others and between 4 minutes and 0 minutes (p<0.05). 3. The tensile bond strength of zinc phosphate cement decreased according to the increase in time of ultrasonic instrument and showed significant difference between 5 minutes and the others (p<0.05). 4. The tensile strength of resin cements showed no statistically differences according to the ultrasonic instrumentation time. In conclusion, it is considered that zinc phosphate cements is most affected by ultrasonic instrumentations and resin cement is the least affected. When using ultrasonic instruments the result avove should be used as an index.