Dentistry ; methods ; Humans ; Minimally Invasive Surgical Procedures

Tooth agenesis is a common human dental anomaly and the agenesis of mandibular second premolars has been proven to be the most frequently observed. The aim of this study is to investigate tooth agenesis and delayed tooth development in patients with agenesis of mandibular second premolars.This study reviewed 9 to 15 year-old patients with agenesis of mandibular second premolars who visited the department of pediatric dentistry of Yonsei University Dental Hospital and took panoramic radiographs from January 2014 to December 2016. On panoramic radiographs, agenesis of teeth was observed and developmental delay of teeth was evaluated by the Nolla method. Among 125 patients with agenesis of mandibular second premolars, 58 patients (46.4%) showed agenesis of other teeth and 38 patients (30.4%) showed delayed tooth development. In this study, patients with agenesis of mandibular second premolars were more likely to have tooth agenesis or delayed eruption of other teeth.
Bicuspid ; Humans ; Methods ; Pediatric Dentistry ; Tooth

Recently computer-aided technology has been widely used in dentistry. DENTCA™ CAD/CAM denture system (DENTCA Inc.), one of CAD/CAM systems for fabricating complete denture, tries to collect and store all of a patient's information at the first visit. This system aims to deliver denture at the second visit through utilizing the CAD/CAM software to access the stored data for designing the 3D denture model. The 3 dimensional (3D) denture will then be fabricated with 3D printer. Many case reports have evaluated clinical application of CAD/CAM system for fabricating complete dentures. This case report is about fabricating of complete dentures using DENTCA system and conventional method in same patient. With two cases, usefulness and limitation of DENTCA system could be evaluated.
Dentistry ; Denture, Complete* ; Dentures ; Humans ; Methods ; Printing, Three-Dimensional

Patient management is considered an important factor in dental field. The aim of this review is to analyze the efficacy of hypnosis to treat fear, anxiety, pain, stress of dental patients, and see how it can be adopted in dentistry for improving patient satisfaction. Medline research was carried out to find the use of hypnosis in dentistry and other aspects of hypnosis in medical area. It can help patient more comfortable, relax, and accordingly reduce patient's negative feelings such as fear, anxiety, pain, stress during dental treatment. Also, it affects patient recovery after surgery by accelerating healing speed and reinforce immune system. When hypnosis is used with other anesthetic method, it can reduce the use of main medication, leading to reduce possibility of side effect. Therefore, using Hypnosis can give patients more comfortable dental experience, both mentally and physically, ultimately making patients more satisfied with the dental treatment.
Anxiety ; Dentistry* ; Humans ; Hypnosis* ; Immune System ; Methods ; Patient Satisfaction*

Efforts to apply augmented reality (AR) technology in the medical field include the introduction of AR techniques into dental practice. The present report introduces a simple method of applying AR during an inferior alveolar nerve block, a procedure commonly performed in dental clinics.
Anesthesia* ; Dental Clinics ; Dentistry ; Mandibular Nerve* ; Methods ; Nerve Block

PURPOSE: This study was to evaluate the wear resistance of 3D printed, milled, and conventionally cured provisional resin materials. MATERIALS AND METHODS: Four types of resin materials made with different methods were examined: Stereolithography apparatus (SLA) 3D printed resin (S3P), digital light processing (DLP) 3D printed resin (D3P), milled resin (MIL), conventionally self-cured resin (CON). In the 3D printed resin specimens, the build orientation and layer thickness were set to 0° and 100 µm, respectively. The specimens were tested in a 2-axis chewing simulator with the steatite as the antagonist under thermocycling condition (5 kg, 30,000 cycles, 0.8 Hz, 5℃/55℃). Wear losses of the specimens were calculated using CAD software and scanning electron microscope (SEM) was used to investigate wear surface of the specimens. Statistical significance was determined using One-way ANOVA and Dunnett T3 analysis (α = .05). RESULTS: Wear losses of the S3P, D3P, and MIL groups significantly smaller than those of the CON group (P < .05). There was no significant difference among S3P, D3P, and MIL group (P > .05). In the SEM observations, in the S3P and D3P groups, vertical cracks were observed in the sliding direction of the antagonist. In the MIL group, there was an overall uniform wear surface, whereas in the CON group, a distinct wear track and numerous bubbles were observed. CONCLUSION: Within the limits of this study, provisional resin materials made with 3D printing show adequate wear resistance for applications in dentistry.
Clothing ; Dentistry ; In Vitro Techniques ; Mastication ; Methods ; Printing, Three-Dimensional

Age estimation is a hot and difficult issue in forensic practice. Teeth are the most solid organs in human body and can be kept in vitro for a long time. With age, the secondary dentin gradually generates and the volume of pulp cavity constantly decreases. Therefore, forensic dentists proposed that age-related changes of dentin-pulp complex could be used to estimate age, which has been widely applied in forensic practice over the years. Due to the development of imaging technology, a variety of methods have been advocated by forensic dentists to detect the age-related changes of dentin-pulp complex for age estimation. However, different methods have their own advantages and limitations, forensic scientists should combine the use of different methods for improving the accuracy of age estimation according to the actual situation. This paper reviews current research of age estimation based on dentin-pulp complex, so as to provide reference for related research.
Age Determination by Teeth ; Dental Pulp ; Dentin ; Forensic Dentistry/methods* ; Humans

Resin infiltration has been used as a treatment option for the management of early caries lesions recently. However, the etching procedure with hydrochloric acid might be somewhat stressful for the clinicians due to safety problem especially for young children, leading to less utility.This study aims at searching for some alternative surface pretreatment methods of resin infiltration for the early caries lesions in primary anterior teeth by comparing penetration depth of various methods.No significant difference was found in penetration ratio between etched surface with 15% hydrochloric acid and 35% phosphoric acid. However, the penetration ratio was significantly higher in groups pretreated either with dental pumice or abrasive metal strip (p < .05).By the result of this study, etching with phosphoric acid as an alternative of hydrochloric acid was thought clinically acceptable as a pretreatment method for resin infiltration in early caries lesions for primary anterior teeth.It was notable that surface conditioning with dental pumice or metal strip before etching was effective in increasing the penetration. This procedural modification might be much more correspondent with minimally invasive concept and hopefully contribute to increased safety and utility in pediatric dentistry.
Child ; Humans ; Hydrochloric Acid ; Methods ; Pediatric Dentistry ; Tooth

Dental Enamel ; surgery ; Dentin ; surgery ; Dentistry, Operative ; methods ; Humans ; In Vitro Techniques ; Laser Therapy ; methods

OBJECTIVETo develop a dental CAD/CAM system with the autonomic intellectual property.

METHOD28 standard teeth crowns were scanned using a newly 3-D laser scanner. As a development platform the Matlab 5.3 were used to process the acquired data, also be used to define the characterized areas on the surfaces of the crowns and to change the crowns form. The software of Surfacer 10.5 to develop a new CAD software for fixed prosthetics, and the 3.5 axis numerical controlled machine to manufacture the prosthetics were used.

RESULTIt is the first time, the 3D graphic data bank of Chinese teeth crowns with a standard form was established. A software of the occlusal adjustment and the form modification were developed. It is also the first time, the authors realized the whole process to use the CAD-CAM for the manufacture of a crown.

CONCLUSIONThe successful result shows, that we have already mastered well the base theory, the mathematics method, the technology of a CAD-CAM system. It provides the basics for the future development.

Computer-Aided Design ; Dental Prosthesis Design ; methods ; trends ; Dental Restoration, Permanent ; methods ; Dentistry, Operative ; methods ; Humans ; Research ; trends ; Research Design