Endodontic microsurgery is defined as the treatment performed on the root apices of an infected tooth, which was unresolved with conventional root canal therapy. Recently, the advanced technology in 3-dimensional model reconstruction based on computed tomography such as cone beam computed tomography has opened a new avenue in application of personalized, accurate diagnosis and has been increasingly used in the field of dentistry. Nevertheless, direct intra-oral localization of root apex based on the 3-dimensional information is extremely difficult and significant amount of bone removal is inevitable when freehand surgical procedure was employed. Moreover, gingival flap and alveolar bone fenestration are usually required, which leads to prolonged time of surgery, thereby increasing the chance of trauma as well as the risk of infection. The purpose of this case report is to present endodontic microsurgery using the guide template that can accurately target the position of apex for the treatment of an anterior tooth with calcified canal which was untreatable with conventional root canal therapy and unable to track the position of the apex due to the absence of fistula.
Apicoectomy ; Cone-Beam Computed Tomography ; Dentistry ; Diagnosis ; Fistula ; Humans ; Microsurgery ; Printing, Three-Dimensional ; Root Canal Therapy ; Tooth

OBJECTIVES: The aim of this study was to evaluate the various NiTi rotary instruments regarding their ability to provide a circular apical preparation. MATERIALS AND METHODS: 50 single canal roots were selected, cut at the cementodentinal junction and the coronal 1/3 of the canals was flared using Gates Glidden burs. Samples were randomly divided into 5 experimental groups of 10 each. In group I, GT files, Profile 04 and Quantec #9 and #10 files were used. In Group II Lightspeed was used instead of Quantec. In Group III, Orifice shaper, Profile .06 series and Lightspeed were used. In Group IV, Quantec #9 and #10 files were used instead of Lightspeed. In Group V, the GT file and the Profile .04 series were used to prepare the entire canal length. All tooth samples were cut at 1 mm, 3 mm and 5 mm from the apex and were examined under the microscope. RESULTS: Groups II and III (Lightspeed) showed a more circular preparation in the apical 1mm samples than the groups that used Quantec (Group I & IV) or GT files and Profile .04 series.(Group V)(p < 0.05) There was no significant difference statistically among the apical 3, 5 mm samples. In 5 mm samples, most of the samples showed complete circularity and none of them showed irregular shape. CONCLUSIONS: Lightspeed showed circular preparation at apical 1 mm more frequently than other instruments used in this study. However only 35% of samples showed circularity even in the Lightspeed Group which were enlarged 3 ISO size from the initial apical binding file (IAF) size. So it must be considered that enlarging 3 ISO size isn't enough to make round preparation.
Nickel ; Titanium ; Tooth

OBJECTIVES: This study was performed to determine whether the combined use of one-bottle self-etch adhesives and composite resins from same manufacturers have better bond strengths than combinations of adhesive and resins from different manufacturers. MATERIALS AND METHODS: 25 experimental micro-shear bond test groups were made from combinations of five dentin adhesives and five composite resins with extracted human molars stored in saline for 24 hr. Testing was performed using the wire-loop method and a universal testing machine. Bond strength data was statistically analyzed using two way analysis of variance (ANOVA) and Tukey's post hoc test. RESULTS: Two way ANOVA revealed significant differences for the factors of dentin adhesives and composite resins, and significant interaction effect (p < 0.001). All combinations with Xeno V (Dentsply De Trey) and Clearfil S3 Bond (Kuraray Dental) adhesives showed no significant differences in micro-shear bond strength, but other adhesives showed significant differences depending on the composite resin (p < 0.05). Contrary to the other adhesives, Xeno V and BondForce (Tokuyama Dental) had higher bond strengths with the same manufacturer's composite resin than other manufacturer's composite resin. CONCLUSIONS: Not all combinations of adhesive and composite resin by same manufacturers failed to show significantly higher bond strengths than mixed manufacturer combinations.
Adhesives* ; Composite Resins* ; Dentin* ; Humans ; Molar

Endodontic treatment of primary molars is a great challenge to the dentists because of their complex morphology. However, there have been limited controlled in vivo studies about filling materials for primary teeth. Hence, the aim of this study is to evaluate and compare histologic responses of different calcium hydroxide canal filling materials that are used in daily clinical practice.Pulpectomies were performed in 132 teeth of the dogs. The root canals were randomly filled with either Vitapex® (n = 44), Metapex® (n = 44), or Metapaste® (n = 44). After 4 or 13 weeks, respectively after operation, the dogs were sacrificed, and teeth were processed for histologic examinations. Inflammatory reaction was evaluated and scored in a blind manner. The Fisher's exact test and Kruskal-Wallis test were used to compare the tested groups.In 4-week-group, all inflammatory responses were in normal range except for fibrosis. In 13-week-group, increased response to various inflammation reaction was shown compared to the 4-week-group. However, there were no statically significant differences between the tested groups in all inflammatory reaction.Overall, there were no significant differences among three materials in responses of apical tissues and all of them showed favorable tissue responses.
Animals ; Calcium Hydroxide ; Dental Pulp Cavity ; Dentists ; Dogs ; Fibrosis ; Humans ; Inflammation ; Molar ; Pulpectomy ; Reference Values ; Tooth ; Tooth, Deciduous

During clinical endodontic treatment, we often find radiopaque filling material beyond the root apex. Accidental extrusion of calcium hydroxide could cause the injury of inferior alveolar nerve, such as paresthesia or continuous inflammatory response. This case report presents the extrusion of calcium hydroxide and treatment procedures including surgical intervention. A 48 yr old female patient experienced Calcipex II extrusion in to the inferior alveolar canal on left mandibular area during endodontic treatment. After completion of endodontic treatment on left mandibular first molar, surgical intervention was planned under general anesthesia. After cortical bone osteotomy and debridement, neuroma resection and neurorrhaphy was performed, and prognosis was observed. But no improvement in sensory nerve was seen following surgical intervention after 20 mon. A clinician should be aware of extrusion of intracanal medicaments and the possibility of damage on inferior alveolar canal. Injectable type of calcium hydroxide should be applied with care for preventing nerve injury. The alternative delivery method such as lentulo spiral was suggested on the posterior mandibular molar.
Anesthesia, General ; Calcium Hydroxide* ; Calcium* ; Debridement ; Female ; Humans ; Mandibular Nerve* ; Molar ; Neuroma ; Osteotomy ; Paresthesia ; Prognosis

PURPOSE: Laparoscopic subtotal cholecystectomy (LSC) can be an alternative surgical technique for difficult cholecystectomies. Surgeons performing LSC sometimes leave the posterior wall of the gallbladder (GB) to shorten the operation time and avoid liver injury. However, leaving the inflamed posterior GB wall is a major concern. In this study, we evaluated the clinical outcomes of standard laparoscopic cholecystectomy (SLC), LSC, and LSC removing only anterior wall of the GB (LSCA). METHODS: We retrospectively reviewed the medical records of laparoscopic cholecystectomies performed between January 2006 to December 2015 and analyzed the outcomes of SLC, LSC, and LSCA. RESULTS: A total of 1,037 patients underwent SLC. 22 patients underwent LSC; and 27 patients underwent LSCA. The mean operating times of SLC, LSC, and LSCA were 41, 74, and 68 minutes, respectively (P < 0.01). Blood loss was 5, 45, and 33 mL (P < 0.05). The mean lengths of postoperative hospitalization were 3.4, 5.4, and 5.8 days. Complications occurred in 24 SLC patients (2.3%), 2 LSC patients (9%), and 1 LSCA patient (3.7%). There was no mortality among the LSC and LSCA patients. CONCLUSION: LSC and LSCA are safe and feasible alternatives for difficult cholecystectomies. These procedures help surgeons avoid bile duct injury and conversion to laparotomy. LSCA has the benefits of shorter operation time and less bleeding compared to LSC.
Bile Ducts ; Cholecystectomy* ; Cholecystectomy, Laparoscopic ; Gallbladder ; Hemorrhage ; Hospitalization ; Humans ; Laparotomy ; Liver ; Medical Records ; Mortality ; Retrospective Studies ; Surgeons

This case report is to present a maxillary first molar with one O-shaped root, which is an extended C-shaped canal system. Patient with chronic apical periodontitis in maxillary left first molar underwent replantation because of difficulty in negotiating all canals. Periapical radiographs and cone-beam computed tomography (CBCT) were taken. All roots were connected and fused to one root, and all canals seemed to be connected to form an O-shape. The apical 3 mm of the root were resected and retrograde filled with resin-modified glass ionomer. Intentional replantation as an alternative treatment could be considered in a maxillary first molar having an unusual O-shaped root.
Adult ; Anatomic Variation ; Apicoectomy ; methods ; Cone-Beam Computed Tomography ; methods ; Dental Pulp Cavity ; diagnostic imaging ; pathology ; Glass Ionomer Cements ; therapeutic use ; Humans ; Male ; Maxilla ; Molar ; diagnostic imaging ; pathology ; Periapical Periodontitis ; therapy ; Retrograde Obturation ; methods ; Root Canal Filling Materials ; therapeutic use ; Root Canal Preparation ; methods ; Tooth Replantation ; methods

This study intended to evaluate noise level of dental handpieces and the effects of noise cancelling devices. An ear model was designed to measure the level of the noise delivered to the inner ear during dental handpiece operation. The level of noise was measured in various conditions using the ear model and the portable noise meter. Noise level was measured again after applying of 4 different noise cancelling devices to the model ear.
The noise level of dental handpieces was 82.5 - 84.4 dB. When 4 types of noise canceling devices were applied, the noise level reduced to 67.4 - 73.8 dB. All 4 devices had statistically significant effect in reducing the noise of the handpiece.
Considering the intensity and exposure time, noise in dental clinics can cause hearing damage to dentists. For protection from the risk of occupational hearing damages, noise canceling devices can be recommended.

PURPOSE: Therapeutic hypothermia (TH) has become a standard strategy for reducing brain damage in the postresuscitation period. The aim of this study is to investigate the outcomes and current performance of TH with out-of-hospital cardiac arrest (OHCA) survivors through the Korean hypothermia network (KORHN) registry. METHODS: We used the KORHN registry, a web-based, multicenter registry that includes 24 participating hospitals throughout the Republic of Korea. Adult comatose OHCA survivors treated with TH from 2007 to 2012 were included. The primary outcomes were neurologic outcome at hospital discharge and in-hospital mortality. The secondary outcomes were TH performance and adverse events during TH. RESULTS: A total of 930 patients were included; of these, 556 (59.8%) patients survived to discharge and 249 (26.8%) were discharged with good neurologic outcomes. The median time from return of spontaneous circulation (ROSC) to the start of TH was 101 (interquartile range (IQR): 46-200) minutes. The induction, maintenance, and rewarming durations were 150 (IQR: 80-267) minutes, 1440 (IQR: 1290-1440) minutes, and 708 (IQR: 420-900) minutes, respectively. The time from the ROSC to coronary angiography was 1,045 (IQR: 121-12,051) hours. Hyperglycemia (46.3%) was the most frequent adverse event. CONCLUSION: Over one quarter of OHCA survivors (26.8%) were discharged with good neurologic outcome. TH performance was managed appropriately in terms of the factors related to the timing of TH, which were the start time for cooling and the rewarming duration.
Adult ; Brain ; Coma ; Coronary Angiography ; Hospital Mortality ; Humans ; Hyperglycemia ; Hypothermia* ; Hypothermia, Induced ; Korea ; Out-of-Hospital Cardiac Arrest* ; Registries ; Republic of Korea ; Rewarming ; Survivors