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1.
Article in English | WPRIM | ID: wpr-893750

ABSTRACT

Background@#The microsporidian parasite Nosema ceranae is a global problem in honeybee populations and is known to cause winter mortality. A sensitive and rapid tool for stable quantitative detection is necessary to establish further research related to the diagnosis, prevention, and treatment of this pathogen. @*Objectives@#The present study aimed to develop a quantitative method that incorporates ultra-rapid real-time quantitative polymerase chain reaction (UR-qPCR) for the rapid enumeration of N. ceranae in infected bees. @*Methods@#A procedure for UR-qPCR detection of N. ceranae was developed, and the advantages of molecular detection were evaluated in comparison with microscopic enumeration. @*Results@#UR-qPCR was more sensitive than microscopic enumeration for detecting two copies of N. ceranae DNA and 24 spores per bee. Meanwhile, the limit of detection by microscopy was 2.40 × 104 spores/bee, and the stable detection level was ≥ 2.40 × 105 spores/ bee. The results of N. ceranae calculations from the infected honeybees and purified spores by UR-qPCR showed that the DNA copy number was approximately 8-fold higher than the spore count. Additionally, honeybees infected with N. ceranae with 2.74 × 104 copies of N. ceranae DNA were incapable of detection by microscopy. The results of quantitative analysis using UR-qPCR were accomplished within 20 min. @*Conclusions@#UR-qPCR is expected to be the most rapid molecular method for Nosema detection and has been developed for diagnosing nosemosis at low levels of infection.

2.
Article in English | WPRIM | ID: wpr-901454

ABSTRACT

Background@#The microsporidian parasite Nosema ceranae is a global problem in honeybee populations and is known to cause winter mortality. A sensitive and rapid tool for stable quantitative detection is necessary to establish further research related to the diagnosis, prevention, and treatment of this pathogen. @*Objectives@#The present study aimed to develop a quantitative method that incorporates ultra-rapid real-time quantitative polymerase chain reaction (UR-qPCR) for the rapid enumeration of N. ceranae in infected bees. @*Methods@#A procedure for UR-qPCR detection of N. ceranae was developed, and the advantages of molecular detection were evaluated in comparison with microscopic enumeration. @*Results@#UR-qPCR was more sensitive than microscopic enumeration for detecting two copies of N. ceranae DNA and 24 spores per bee. Meanwhile, the limit of detection by microscopy was 2.40 × 104 spores/bee, and the stable detection level was ≥ 2.40 × 105 spores/ bee. The results of N. ceranae calculations from the infected honeybees and purified spores by UR-qPCR showed that the DNA copy number was approximately 8-fold higher than the spore count. Additionally, honeybees infected with N. ceranae with 2.74 × 104 copies of N. ceranae DNA were incapable of detection by microscopy. The results of quantitative analysis using UR-qPCR were accomplished within 20 min. @*Conclusions@#UR-qPCR is expected to be the most rapid molecular method for Nosema detection and has been developed for diagnosing nosemosis at low levels of infection.

3.
Article in Korean | WPRIM | ID: wpr-919875

ABSTRACT

The purpose of this study is to evaluate the position of the mandibular foramen and location and morphological characteristics of the mandibular lingula using Cone-Beam Computed Tomography (CBCT).Mandibular CBCT images of children aged 6 - 16 years were collected. A total of 180 patients were divided into 3 groups, 6 - 7, 10 - 11 and 15 - 16 years, with 30 male and female patients per group. Either side of the ramus was analyzed. The shortest distances from the anterior, posterior, superior and inferior border of the ramus to the mandibular lingula were measured. The shortest distance between the mandibular lingula and the mandibular foramen was also measured. The vertical distance from the mandibular lingula and the mandibular foramen to the occlusal plane was measured. The shapes of the mandibular lingula was classified into 4 types according to the criteria.The distances of the mandibular lingula from the anteroposterior and vertical reference points of the ramus increased in all directions with age. The distance between the mandibular lingula and the mandibular foramen also increased with age. The location of the mandibular lingula and the mandibular foramen in relation to the occlusal plane moved upwards with age. The most common shape of the mandibular lingula was triangular, followed by nodular, truncated and assimilated, and there was no difference in the shape according to age.It is recommended that the horizontal insertion point of the anesthesia from the anterior border of the ramus increased to 17 mm, 18 mm, and 19 mm according to the age groups. It is also suggested that the vertical insertion point increased by 2 - 3 mm, 5 - 6 mm and 9 - 10 mm above the occlusal plane according to the age groups.

4.
Article in Korean | WPRIM | ID: wpr-919866

ABSTRACT

Color stability of pulp-capping material is considered vital to the final aesthetic result since the material is placed in the coronal area. The purpose of this study was to compare the color stability of various pulp-capping materials by analyzing color change of tooth over time. A cavity was formed in the crown of the extracted premolar, and 4 types of pulp-capping materials were filled. Color assessment was performed with a spectrophotometer at different intervals: before placement; immediately after material placement; 1 day, 1 week, 2 weeks, 4 weeks, 8 weeks, 12 weeks, and 16 weeks after placement. Proroot white MTA® and TheraCal LC® showed a significant decrease in the L* value and an increase in the ΔE* value over time. In contrast, Biodentine® and Well-Root™ PT showed no significant change in the L* value and maintained a steady ΔE* value. The application of pulp-capping materials containing bismuth oxide as a radiopacifier may result in a color change of teeth. Long-term color stability of pulp-capping materials should be considered when treating teeth with thin enamel thickness or in aesthetically important area.

5.
Article in Korean | WPRIM | ID: wpr-919864

ABSTRACT

The purpose of this study was to develop prototype of virtual reality(VR) simulation with malocclusion models and evaluate its applicability. Task abilities, task completion time, and a satisfaction survey were compared between dentist trainees and dental students. Participants were instructed to observe virtual malocclusion models and then performed three tasks to diagnose the type of malocclusion, determine clinical findings and develop treatment plans. Their satisfaction with the simulation experience were evaluated using a questionnaire containing five questions. Task abilities of trainees related to clinical features and treatment plans were significantly higher than that of students(p < 0.01). In both groups, the task completion time for the second case was significantly reduced compared to that for the first case(p < 0.01). The satisfaction survey showed high scores and positive responses for this simulation in both groups. If the prototype of VR simulation is continuously advanced, it will be applicable for orthodontic education in pediatric dentistry.

6.
Article in Korean | WPRIM | ID: wpr-919858

ABSTRACT

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked recessive disorder and is the most common enzyme deficiency worldwide. Although this disease is rare in Korea, its prevalence may increase due to an increase of multicultural families. Patients with this deficiency are prone to hemolytic anemia provoked by specific drugs commonly used or prescribed in pediatric dentistry. It is necessary for pediatric dentists to have accurate knowledge of a patient's medical history and to consult with a pediatric hematologist to avoid oxidative stress that can lead to hemolysis. The most effective treatment is prevention of exposure to factors that may trigger anemia. Appropriate education regarding risk factors is essential for patients diagnosed with this disease. This case report aimed to discuss the drugs and dental management methods that should be cautious in children with G6PD deficiency.

7.
Article in English | WPRIM | ID: wpr-893716

ABSTRACT

Fast and accurate detection of viral RNA pathogens is important in apiculture. A polymerase chain reaction (PCR)-based detection method has been developed, which is simple, specific, and sensitive. In this study, we rapidly (in 1 min) synthesized cDNA from the RNA of deformed wing virus (DWV)-infected bees (Apis mellifera), and then, within 10 min, amplified the target cDNA by ultra-rapid qPCR. The PCR products were hybridized to a DNA-chip for confirmation of target gene specificity. The results of this study suggest that our method might be a useful tool for detecting DWV, as well as for the diagnosis of RNA virus-mediated diseases on-site.

9.
Article in English | WPRIM | ID: wpr-901420

ABSTRACT

Fast and accurate detection of viral RNA pathogens is important in apiculture. A polymerase chain reaction (PCR)-based detection method has been developed, which is simple, specific, and sensitive. In this study, we rapidly (in 1 min) synthesized cDNA from the RNA of deformed wing virus (DWV)-infected bees (Apis mellifera), and then, within 10 min, amplified the target cDNA by ultra-rapid qPCR. The PCR products were hybridized to a DNA-chip for confirmation of target gene specificity. The results of this study suggest that our method might be a useful tool for detecting DWV, as well as for the diagnosis of RNA virus-mediated diseases on-site.

10.
Article in Korean | WPRIM | ID: wpr-919849

ABSTRACT

Proper treatment of an impacted tooth is required as it causes functional and esthetic disharmony, as well as it can cause root absorption of adjacent teeth. Treatment options for impacted teeth include periodic observation, surgical exposure, orthodontic traction followed by surgical exposure, tooth transplantation, and extraction. Modified Nance appliance, used for orthodontic traction, is clinically useful because it does not require patient cooperation. Through orthodontic traction combined with surgical exposure of impacted maxillary incisors, canines, and molars using modified Nance appliance, adequate results can be obtained.

11.
Article in Korean | WPRIM | ID: wpr-919848

ABSTRACT

Epidermoid cysts are rare benign lesions in the oral cavity that may be either congenital or acquired. The cysts are usually slow-growing and asymptomatic until becoming secondarily infected or large enough to interfere with mastication and speech. Consequently, diagnosis is often delayed. The condition is also uncommon in newborns and infants. Most of the lesions occur in the floor of the mouth and rarely in the upper lip. This report describes the case of a 29-month-old girl with a palpable mass in the inner mucosa of the upper lip. The lesion was surgically enucleated using an intraoral approach and histopathologically diagnosed as epidermoid cyst.

12.
Article in Korean | WPRIM | ID: wpr-919838

ABSTRACT

The purpose of this study was to determine whether the palatal rugae could be used as an appropriate reference area for serial model superimposition following Rapid maxillary expansion(RME) and facemask treatment.A total of 52 pediatric patients who had undergone RME and facemask treatment were selected. Palate and palatal rugae in the pre- and post- treatment casts from the patients were measured.In spite of dentoalveolar changes occurred by RME and facemask, anteroposterior changes in palate and palatal rugae were not significant. Anatomical changes of palate and palatal rugae were mostly shown in the transverse dimension. The soft tissue of the palatal rugae stretches in adaptation to hard tissue movement. Among the evaluated landmarks, the medial point of the third palatal rugae seemed to be the most stable.The observed alterations in the palatal rugae demonstrated the potential of medial points of third palatal rugae as a reference point in model superimpositions to evaluate dental movement within the maxillary arch following RME and facemask treatment.

13.
Article in Korean | WPRIM | ID: wpr-919827

ABSTRACT

The purpose of this study is to evaluate the morphological characteristics of the roots and roots canals of primary molar teeth using Cone-Beam Computed Tomography (CBCT).A total of 68 CBCT images of children aged 4 - 5 years was used for this study. A total of 160 molar teeth were analyzed. Various parameters such as the number of roots and canals, length of root and root canal, and the angulation and shape of the roots were analyzed.All maxillary primary molars had 3 roots. The presence of 2 root canals in 1 root was only observed in the mesiobuccal root of maxillary primary second molars. Most mandibular primary molars had 2 roots, and most mesial roots had 2 root canals.Concerning the length of the roots, the palatal root of the maxillary primary molar was found to be longest whereas the distobuccal root was shortest. In mandibular primary molars, the mesial root was longer than the distal root. In maxillary primary molars, the palatal root had the greatest angulation whereas the distal root has the greatest in mandibular molars. The root and root canals of maxillary primary molars were more curved in shape whereas mandibular primary molars were straight.

14.
Article in Korean | WPRIM | ID: wpr-919813

ABSTRACT

The purpose of this study was to evaluate the applicability of virtual reality simulation after experience of dental caries diagnosis for dental students before exposing to clinical pediatric practice. A pediatric patient model of a five-year-old child with primary dentition was developed and a caries model that is amenable to VR(virtual reality) diagnosis was organized and set-up. The dental student’s were allowed to use the simulated model for fifteen minutes and their experiences were evaluated using a self-reported questionnaire to evaluate presence and usability of this application. Overall, virtual presence and appearance area of the simulation were highly scored. The result indicates that the VR model has no significant difference from the actual clinical caries regardless of grade of students, gender and VR experience. If the prototype is continuously advanced, its applicability in dental education will increase.

15.
Article in Korean | WPRIM | ID: wpr-787385

ABSTRACT

The purpose of this study was to examine dental complications and to evaluate the effects of initial treatment age, treatment modalities, and treatment duration on the disorder after radiation and chemotherapy in pediatric cancer patients.For 93 children with clinical and radiographic data, the number of teeth, the morphology of teeth, the shape of the roots, and development status of the dentition were evaluated.Dental development disorders were found in 61.3% of the children. The mostly found abnormality was root deformity with the prevalence of 31.2%. In children submitted to the therapy before the age of 6, the number of missing teeth (p = 0.029) and microdontia (p = 0.003) were greater compared to the children who started to receive the treatment after the age of 6. The combination of radiation and chemotherapy showed significantly greater incidences of missing teeth (p = 0.030), microdontia (p = 0.046), and root deformity (p = 0.009) when compared with the sole application of chemotherapy. When the children were submitted to anticancer therapy for 18 months or longer duration, greater number of missing teeth (p = 0.032), microdontia (p = 0.011), root deformity (p = 0.025), and total number of teeth affected (p = 0.036) were observed compared with duration less than 18 months.The number of dental abnormalities increased when the children were treated at earlier ages, with combination of radiation and chemotherapy, and for longer period of time.


Subject(s)
Child , Congenital Abnormalities , Dentition , Drug Therapy , Humans , Incidence , Prevalence , Tooth
16.
Article in Korean | WPRIM | ID: wpr-787348

ABSTRACT

Post-endodontic restorations are both important and challenging for clinical success in endodontically treated posterior teeth. Several options have been proposed to restore endodontically treated molars.In pediatric dentistry, restoration using conventional single crowns, especially for partially erupted molars with insufficient retentive tooth structure, has proven to be difficult. However, the endocrown presents a conservative and esthetic restorative alternative to conventional crowns with post-and-core, as it acquires additional retention within the pulp chamber. The tooth preparation consists of a circular, equigingival, butt-joint margin and a central retention cavity in the pulp chamber that helps to construct both the crown and core as a single unit.This case report describes the esthetic and conservative endocrown restorations of erupting permanent first molars with extensive coronal destruction.


Subject(s)
Crowns , Dental Pulp Cavity , Molar , Pediatric Dentistry , Tooth , Tooth Preparation
17.
Article in Korean | WPRIM | ID: wpr-787341

ABSTRACT

The purpose of this study was to evaluate the effect of the intracanal medicaments on the push-out bond strength of the calcium silicate-based materials.Forty extracted single-root human mandibular premolars were sectioned below cementoenamel junction. Standardized root canal dimension was obtained with a parallel post drill. The specimens were randomly divided into a control group (no medicament), and experimental groups received medicaments with either CH (calcium hydroxide), DAP (double antibiotic paste; a mixture of ciprofloxacin and metronidazole), or TAP (triple antibiotic paste; a mixture of minocycline, ciprofloxacin and metronidazole). Following removal of medicaments with irrigation, roots were cut into sections with 1-mm-thickness. Thereafter, calcium silicate-based materials are applied to the specimens : (i) ProRoot MTA® and (ii) Biodentine®. A push-out bond strength was measured and each specimen was examined to evaluate failure mode.Intracanal medication using CH significantly increased the bond strength to the root dentin. But there are no significant differences on the bond strength of ProRoot MTA® or Biodentine® among TAP, DAP and control groups. The dislodgement resistance of Biodentine® from root dentin was significantly higher than that of ProRoot MTA® regardless of the type of intracanal medicaments.


Subject(s)
Bicuspid , Calcium , Ciprofloxacin , Dental Pulp Cavity , Dentin , Humans , Minocycline , Tooth Cervix
18.
Article in Korean | WPRIM | ID: wpr-787329

ABSTRACT

The aim of this study was to evaluate the effect of etching time and bonding agents on bond strength of sealant applied to the occlusal surface of primary molars.Forty non-carious exfoliated human primary molars were included in the study. The teeth were randomly divided into 4 groups for measurement. For group I, no acid etching treatment was used. For group II, III, and IV, acid etching gels were applied on the occlusal surface for 15, 30, and 60 seconds, respectively. Each group was divided into 2 subgroups; one group was treated with bonding agents on the enamel while the other was not. Microtensile bond strength was evaluated using a universal testing machine.There were no statistically significant differences in bond strength with varying duration of etching among groups. The results revealed that the use of bonding agents prior to application of fissure sealant increased the bond strength(p < 0.05).It could be concluded that etching time greater than 15 seconds does not significantly enhance the bond strength, but the use of bonding agents as an intermediate layer between the primary molar and fissure sealant would be beneficial in increasing the bond strength.


Subject(s)
Dental Enamel , Gels , Humans , Molar , Pit and Fissure Sealants , Tooth
19.
Article in Korean | WPRIM | ID: wpr-787303

ABSTRACT

Osteopetrosis is characterized by impaired osteoclast function and increased bone density. Infantile osteopetrosis is a severe form of the disease and has characteristics such as diffusely sclerotic skeleton, pancytopenia, cranial nerve entrapment, infection susceptibility, and abnormal craniofacial appearance. Patients with infantile osteopetrosis often experience developmental delay, and may have a short life span.A 14-month-old girl with osteopetrosis presented to the department of pediatric dentistry. Incipient caries on deciduous incisors were observed. The patient revisited 4 years of age. Besides medical problems, oral complications such as growth retardation, narrow upper arch, crowding, dental caries, and abnormal tooth development were observed. After consultation with her pediatrician, dental treatments were performed on the deciduous molars under sedation after a prophylactic antibiotic injection. At a periodic follow-up, multiple deciduous teeth were treated and extracted, and oral-rehabilitation with a removable partial denture was initiated.Patient with osteopetrosis are highly susceptible to infection because of their compromised immune system and problems associated with wound healing that lead to osteomyelitis or sepsis development.Active participation in dental care for sugar intake management and proper oral hygiene are obligatory.


Subject(s)
Bone Density , Cranial Nerves , Crowding , Dental Care , Dental Caries , Denture, Partial, Removable , Female , Follow-Up Studies , Humans , Immune System , Incisor , Infant , Molar , Oral Hygiene , Osteoclasts , Osteomyelitis , Osteopetrosis , Pancytopenia , Pediatric Dentistry , Sepsis , Skeleton , Tooth , Tooth, Deciduous , Wound Healing
20.
Article in Korean | WPRIM | ID: wpr-787292

ABSTRACT

This study aimed to evaluate the nasopharyngeal and oropharyngeal dimensions of the patients with skeletal class II division 1 or division 2 patterns during the pre-peak, peak, and post-peak growth periods for comparison with a skeletal class I control group (79 for pre-peak, 40 for peak, 40 for post-peak). Total 159 lateral cephalograms (70 for skeletal class I, 51 for skeletal class II, division 1, and 38 for skeletal class II, division 2) were selected.The growth of anteroposterior dimension of the pharyngeal airway were statistically significant among growth periods. The dimension for the nasopharyngeal and oropharyngeal airway space was the smallest in the division 1 skeletal class II group followed by class II division 2 and skeletal class I.


Subject(s)
Adolescent , Humans
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