Osteomyelitis on the Mandibular Malunion and Nonunion Site: A Case Report

Song, Chi-Woong,Yoon, Hyun-Joong,Lee, Sang-Hwa Korean Academy of Dental Science 2013 Journal of korean dental science Vol.6 No.2

The proper management of mandibular fractures involves reduction, rigid fixation, and immobilization to allow bone healing. Nonunion or malunion at the fractured sites is a well-known complication of fracture when the treatments are inappropriate. We present a case of left mandibular fracture due to shrapnel during the Korean War. The patients did not receive appropriate treatment at that time, so nonunion and malunion developed. Sixty years after the accident, mandibular osteomyelitis on the fracture site developed due to dental-origin inflammation. The treatment was based on relatively conservative care, such as saucerization and administration of antibiotics. There was no complication during the short-term follow-up. We present the case with literature review.

The Role of Autonomous Wntless in Odontoblastic Differentiation of Mouse Dental Pulp Cells

Choi, Hwajung,Kim, Tak-Heun,Ko, Seung-O,Cho, Eui-Sic Korean Academy of Dental Science 2016 Journal of korean dental science Vol.9 No.1

Purpose: Wnt signaling plays an essential role in the dental epithelium and mesenchyme during tooth morphogenesis. Deletion of the Wntless (Wls) gene in odontoblasts appears to reduce canonical Wnt activity, leading to inhibition of odontoblast maturation. However, it remains unclear if autonomous Wnt ligands are necessary for differentiation of dental pulp cells into odontoblast-like cells to induce reparative dentinogenesis, one of well-known feature of pulp repair to form tertiary dentin. Materials and Methods: To analyze the autonomous role of Wls for differentiation of dental pulp cells into odontoblast-like cells, we used primary dental pulp cells from unerupted molars of Wls-floxed allele mouse after infection with adenovirus for Cre recombinase expression to knockout the floxed Wls gene or control GFP expression. The differentiation of dental pulp cells into odontoblast-like cells was analyzed by quantitative real-time polymerase chain reaction. Result: Proliferation rate was significantly decreased in dental pulp cells with Cre expression for Wls knockout. The expression levels of Osterix (Osx), runt-related transcription factor 2 (Runx2), and nuclear factor I-C (Nfic) were all significantly decreased by 0.3-fold, 0.2-fold, and 0.3-fold respectively in dental pulp cells with Wls knockout. In addition, the expression levels of Bsp, Col1a1, Opn, and Alpl were significantly decreased by 0.7-fold, 0.3-fold, 0.8-fold, and 0.6-fold respectively in dental pulp cells with Wls knockout. Conclusion: Wnt ligands produced autonomously are necessary for proper proliferation and odontoblastic differentiation of mouse dental pulp cells toward further tertiary dentinogenesis.

Factors Affecting Dental Fear in Korean Adolescents

Kim, Ah-Hyeon,Ahn, Eun-Suk,An, So-Youn Korean Academy of Dental Science 2017 Journal of korean dental science Vol.10 No.1

Purpose: The purpose of this study was to evaluate the dental fear experienced among Korean adolescents and to identify the relevant factors. Materials and Methods: In order to compare the level of dental fear depending on the subjects' previous experience, descriptive statistical analysis was performed. Gender- and grade-dependent evaluation was performed according to the presence of their previous dental visit and dental fear. Subjective oral health status was also investigated. In order to determine the factors affecting dental fear, logistic regression analysis was performed. Result: Among the total of 333 subjects who had experienced dental fear, females were found to experience 1.766 times greater dental fear than males (P=0.007). The worse subjective perception of their oral health was associated with increase in the experience of dental fear by 1.245-fold (P=0.047). Conclusion: The dental fear was likely to be formed during the visit to the dentist's office or through previous experience of dental treatment. Therefore in order to reduce the fear associated with dental treatment in adolescents, establishemnt of a proper environment in the dental clinic and a patient management program are necessitated.

Retrospective Study on the Flow and Characteristics of Dental Emergency Patients in Chosun University Hospital

Lee, Sung-Suk,Kim, Su-Gwan,Oh, Ji-Su,Moon, Seong-Yong,You, Jae-Seek,Yu, Kyoung-Hwan,Jo, Ji-Ho,Park, Jin-Sung,Yang, Wang-Sik,Seo, Dong-Kook Korean Academy of Dental Science 2015 Journal of korean dental science Vol.8 No.1

Purpose: The aim of the present study is to assess the importance of proper treatment timing for dental emergency patients by characterizing current patient care in the emergency room. Materials and Methods: A retrospective chart review of 3,211 patients who visited the Chosun University Hospital's dental emergency department (Gwangju, Korea) was conducted from January 1, 2011 to May 31, 2014. Information regarding age, gender, onset date, main causes, and diagnoses were collected and analyzed. The main causes were divided into six categories: assault, household/play, sports, traffic, work, and others. Result: Emergency visits were more common for men (69%), and the ratio of males to females was 2.2:1 On average, the major cause was household/play (49.8%), followed by others (18.9%), traffic (16.6%), assault (9.1%), sports (2.9%), and work (2.6%). The most frequent diagnosis on average was dental trauma with 82.4%, followed by infection (10.7%), others (4.7%), and bleeding (2.2%). Conclusion: The main reasons for visits to the dental emergency department are dental trauma, dental infection, bleeding, and others. The most frequent reason for dental emergency patients to visit the emergency department was dental trauma (82.4%).

Retrospective Clinical Study on Flapless Implant Placement

Kim, Jong-Hee,Kim, Young-Kyun,Yi, Yang-Jin Korean Academy of Dental Science 2012 Journal of korean dental science Vol.5 No.2

Purpose: The purpose of this study was to evaluate the prognosis (clinical outcomes) of one-stage flapless implant surgery based on success and survival rate and marginal alveolar bone loss. Materials and Methods: Ninety dental implants were placed according flapless surgical procedure in forty-one patients at Hospital between April 2004 and May 2009. The mean age of the patients was 54, and the patients were comprised of 24 men and 17 women. Each patient was investigated radiographically and clinically being with average follow up 49.7 period. Result: Average healing period is 4.45 month (maxilla: 5.31 month, mandible: 3.20 month) after installation and survival rate is 95.7% in this period. The survival rate and success rate at 1 year after function (prosthodontics setting) are 92.4% and 88.0%. At final observation, the survival rate and success rate are 90.2% (maxilla: 89.1%, mandible: 92.9%) and 84.8% (maxilla: 82.8%, mandible: 89.3%). The mean residual alveolar bone resorption at 1-year after function and final observation are 0.8 mm and 1.07 mm. Conclusion: Our study suggest that if appropriate surgical technique with proper patients selection, flapless implants surgery is predictable simple and safety technique.

Comparative Biomechanical Study of Self-tapping and Non Self-tapping Tapered Dental Implants in Artificially Simulated Quality 2 Bone

Baek, Yeon-Wha,Kim, Duck-Rae,Park, Ju-Hee,Lim, Young-Jun Korean Academy of Dental Science 2011 Journal of korean dental science Vol.4 No.2

Purpose: Modifications of implant design have been related to improving initial stability. The purpose of this study was to investigate their respective effect on initial stability between two tapered implant systems (self-tapping vs. non-self-tapping) in medium density bone using three different analytic methods. Materials and Methods: Self-tapping implant (GS III$^{(R)}$; Osstem Implant Co., Busan, Korea) and non-self-tapping implant (Replace Select$^{(R)}$; Nobel Biocare, G$\H{o}$teborg, Sweden) were investigated. In Solid rigid polyurethane blocks of artificially simulated Quality 2 bone, each of the 5 implants was inserted according to the manufacturer's instructions for medium-bone drilling protocol. Evaluation of initial stability was carried out by recording the maximum insertion torque (IT) and performing the resonance frequency analysis (RFA), and the pull-out test. Results: The IT and RFA values of self-tapping implant were significantly higher than those of non self-tapping implant (P=.009 and P=.047, respectively). In the pull-out values, no significant differences were found in implants between two groups (P=.117). Within each implant system, no statistically significant correlation was found among three different outcome variables. Conclusions: These findings suggest that design characteristics of implant geometry significantly influence the initial stability in medium bone density.

Improved Cleaning Method for Dental Instruments

Kim, In-Geol,Lee, Yun-Ji Korean Academy of Dental Science 2010 Journal of korean dental science Vol.3 No.2

We searched at the "PubMed.gov" and "jendodon.com" sites to conduct a literature review on dental instruments that are reused in clinical settings and on infection control involving pre-disinfection or sterilization cleaning/rinsing. The keyword "dental clean" was used for the Web search. We found the present official definition of instrument cleaning performed prior to disinfection or sterilization rather limiting ("removal of foreign matter (soil, organism, etc.) from the instruments"). Thus, we proposed to expand the definition to include the removal of oils applied to protect the metallic instruments and from corrosion, stains, and rust resulting from the frequent reuse of the instruments. Clinicians are found to clean their dental instruments (a) immediately after treating their patients or (b) following their treatment but not immediately afterward. In the latter case, we recommend presoaking to be added. Ultrasonic sterilization of 5~15 minutes is found to be more effective in terms of eliminating residual matter from the instruments compared to other methods. To check on the cleaning results, we recommend visual inspection, which can be quick and practical in clinical settings. The latest products being developed and marketed on the market address the related problems. Nonetheless, research must be continued on the effects of presoak, cleaning/rinsing, disinfection, and high-temperature or heating-based sterilization on the dental instruments and on dental clinicians' practices in cleaning, disinfection, and sterilization. We advise dental clinicians to select the proper cleaning methods and detergents for their instruments to help eliminate or prevent corrosion, staining, and rusting, to reduce the maintenance costs, and to ensure user-friendly instruments/apparatuses.

Success and Failure of Surgical Endodontic Treatment in Molar Teeth

Geum, Yun-Seon,Lee, Jang-Ryeol,Kim, Hyeon-Cheol,Lee, Sang-Cheol,Kim, Yeong-Uk Korean Academy of Dental Science 2010 Journal of korean dental science Vol.3 No.2

Despite the latest advancement made in its techniques and devices/apparatuses and the resulting rising expectation in the field of dental surgery, apicoectomy performed in the molar teeth remains a technical challenge and lacks evidence substantiated by long-term follow-up studies. This study sought to investigate the treatment outcomes and post-operative success rate in the root-end resected molar teeth accompanied by a high level of surgical risks due to their close proximity to the mandibular canal and maxillary sinus. A total of 68 patients who received treatment at Livingwell Dental Hospital between 2004 and 2010 and underwent apical surgery in the maxillary or mandibular molar area were enrolled in this study. A total of 160 roots collected from 75 molar teeth were subjected to surgical endodontic treatment and subsequently evaluated clinically as well as radiographically. Based on the results of the study, the clinical success rate was found to be 78.8% in cases involving radiological healing. Likewise, 90.7% of the roots recorded a robust clinical survival rate, but with incomplete healing as shown by radiography. The results indicate that the apical procedure involving molar teeth is a prognosis-friendly method that promises positive outcomes and higher success rate based on long-term follow-up observations.

Full Mouth Rehabilitation of a Patient with Bite Collapse in the Molar Area Using Removable Partial Denture and Dental Implant Prosthetics

Hong, Jun-Won,Seo, Jae-Min,Seong, Dong-Hwan,Song, Gwang-Yeop,Park, Ju-Mi,Ahn, Seung-Geun Korean Academy of Dental Science 2010 Journal of korean dental science Vol.3 No.2

Dental clinicians often encounter cases wherein the patient's lost molar area was neglected and left untreated for an extended period of time, thereby causing the extrusion of opposite molars and occlusal disharmony as well as occlusion in the anterior teeth and consequently resulting in anterior displacement in the area. Clinicians normally carry out prosthetic treatment via occlusal plane lifting when such becomes absolutely necessary due to the lack of sufficient space needed for prosthetic therapy aimed at proper anterior and lateral induction. In this case report, we examined occlusal disharmony and VDO loss in a patient who had lost his molars and had not received prosthetic treatment for an extended period of time. We treated the maxillary area with dental implant prosthetics and Kennedy Class I RPD and the mandibular area with residual natural tooth-based implant placement and dental implant prosthetics. The patient reported treatment outcomes that were deemed satisfactory both functionally and aesthetically.

Clinical Study of Natural Recovery of Altered Sensation after Minor Dental Surgery

Kim, Jong-Hwa,Yun, Pil-Young,Kim, Young-Kyun Korean Academy of Dental Science 2011 Journal of korean dental science Vol.4 No.1

Purpose: The aim of our study was to evaluate natural recovery of neurologic injury after minor dental surgery based on subjective neurologic evaluation. Materials and Methods: From December 2005 through July 2009, 30 patients from Seoul National University Bundang Hospital were identified as having been treated with minor dental surgery. The patients were composed of 12 men and 18 women, with a mean age of 50.6 years. The median duration of this study was 62 weeks. Results: The patients were treated by implants (17 cases), tooth extractions (6 cases), bone grafts (4 cases), inferior alveolar nerve transpositions (2 cases) and periodontal surgery (1 case) prior to the occurrence of altered sensation. Areas of altered sensation after minor surgery included the lip (36.7%), chin (30.0%) and tooth (21.7%), and at final follow-up, there was no change of ranking. Altered sensations expressed by patients included numbness (33.3%), discomfort (22.9%), relieving sense (14.6%), tingling (14.6%) and itching (14.6%). There was no change of ranking of altered sensation at the last follow-up. Patients experienced the altered sensation always (47.8%), during tactile stimulation (26.1%), when chewing food (13.0%), and talking (13.0%). Mean visual analogue scale (VAS) was $3.43{\pm}2.84$ for pain and $6.64{\pm}2.72$ for paresthesia. VAS of pain was decreased significantly between the first visit and the end of follow-up, and paresthesia also showed a significant difference. Conclusion: Altered sensations may occur at any time after minor dental surgery, but we observed that natural recovery of altered sensation occurred as time went on.