Intentional Replantation to Treat Apical Periodontitis of Maxillary First Molar with Foreign Body Located Outside Apical Foramen Using CBCT: A Case Report.

The recent use of cone beam computed tomography (CBCT) in the field of dentistry to obtain 3-dimensional (3D) images has enabled more effective examination and diagnosis in endodontic treatment. Such information has also been reported to be of benefit in surgical endodontic treatment such as intentional replantation. Here, we report a case of intentional replantation with the assistance of CBCT in which a good therapeutic outcome was achieved. The patient was a 30-year-old woman who visited our hospital with the chief complaint of spontaneous pain in the right maxillary first molar. Dental radiographs revealed a radiolucent area in the apical portion of the distal root, and a radiopaque area thought to be a broken shard from a small surgical instrument measuring approximately 1.5 mm in length. The shard was located outside the distal apical foramen. Based on these findings, the diagnosis was acute suppurative apical periodontitis of the right maxillary first molar. Infected root canal therapy was subsequently commenced. The patient's symptoms showed no improvement, however, and the pain persisted. Therefore, dental CBCT was performed to obtain 3D images, which confirmed a radiopaque area thought to be a broken shard from a small surgical instrument located outside the apical foramen of the distal root and facing in a direction that made it impossible to remove from the root canal. Because the patient's symptoms had shown no improvement and a foreign body was observed outside the apical foramen, intentional replantation combined with root resection was performed with informed consent. At a 1-year follow-up visit, progress was good, and there were no reported symptoms or signs. When reaching a diagnosis is difficult based on clinical findings and dental radiographs alone, the 3D images provided by CBCT offer a means of securing a more reliable diagnosis, allowing planning of treatment to be more effective.

CBCT-based Diagnosis of Periapical Lesion of Maxillary First Premolar Mimicking That of Second Premolar.

Apical periodontitis is usually diagnosed based on clinical findings and dental X-rays. Recently, however, dental cone beam computed tomography (CBCT), which provides 3-D images of the maxillofacial region, has enabled dentists to examine patients undergoing endodontic therapy more effectively, improving diagnostic accuracy. Here, we describe a positive treatment outcome achieved using CBCT to diagnose apical periodontitis of the maxillary premolars, which had proven difficult to diagnose based on clinical findings and dental radiography alone. The patient was a 42-year-old Japanese man who presented with the chief complaint of gingival swelling in the maxillary right premolar region. Our initial diagnosis, based on clinical findings and dental X-ray, was apical periodontitis of the maxillary right second premolar, and treatment was started. However, after the patient failed to respond to the treatment, CBCT was performed. Based on these new findings, the diagnosis was changed to one of apical periodontitis of the upper right first premolar, and the patient was treated accordingly. Previous studies have described the complex anatomical morphology of the upper premolars, noting multiple roots and variation in the morphology of the root canals. The 3-D images provided by dental CBCT allow better assessment of oral conditions than the traditional 2-D images provided by dental X-rays, which in turn enables the dentist to better select the most appropriate treatment. Here, the patient showed no symptoms and was progressing well at a 6-month follow-up visit. The present results indicate that when clinical findings and dental X-rays alone are insufficient to allow a secure diagnosis, CBCT offers an effective alternative which will enable the appropriate treatment to be selected more reliably.

Analysis of Needlestick and Similar Injuries over 10 Years from April 2004 at Tokyo Dental College Chiba Hospital.

Here we investigated needlestick and similar injuries reported over a 10-year period between April 2004 and March 2014. The purpose of this study was to prevent recurrence and reduce the incidence of such injuries at Tokyo Dental College Chiba Hospital. The Division of Medical Risk Management at Chiba Hospital anonymized the data to protect personal information prior to analysis. A total of 213 injuries occurred over the 10-year period investigated, but the number of cases decreased yearly. Many cases involved dental undergraduate students and dentists, followed by trainee dentists, students at the school of dental hygiene, nurses, dental hygienists, and cleaners. Suture needles, followed by injection needles, were the top two most common injury-causing instruments, contributing to approximately 50% of the total number of such cases. Many injection needle injuries occurred during tidying up, while those caused by suture needles occurred during dental treatment. Taken together, these findings suggest the importance of strict adherence to guidelines provided in safety manuals on error-free procedures and handling of instruments. Improvement in the ability to sense potential risk is essential if such injuries are to be avoided.

Personality traits in patients with oral malodor.

Many patients presenting at oral malodor clinics have psychological halitosis, which is characterized as being obsessive about having oral malodor or being distressed from a keen awareness of oral odor. We used the Tokyo University Egogram (TEG) to evaluate personality traits in patients presenting at the oral malodor clinic of this institute. The incidence of each TEG personality type was compared between a total of 600 patients presenting at the clinic and a cohort of healthy individuals. Differences were found between the malodor patient and healthy groups. Nurturing Parent (NP)-dominant, Adult (A)-dominant, inverse N (NP low, Free Child high), showed a significant decrease of 6.7, 11.3, and 3.6%, respectively; whereas N (A low) and N (NP high, Free Child low) showed a significant increase of 3.3 and 6.4%, respectively (p < 0.01).

An endodontic-periodontal lesion with primary periodontal disease: a case report on its bacterial profile.

The microflora in the periodontal pockets can affect the dental pulp and cause endodontic-periodontal lesions or retrograde pulpitis. Here we report an endodontic-periodontal lesion together with its bacterial profile. The lesion occurred in the maxillary right first molar of a 40-year-old woman who presented at our hospital complaining of a violent toothache since the previous night. Clinically, the tooth was caries-free and an electric pulp test showed it to be vital. The tooth showed signs of advanced periodontitis and the periodontal pocket was deep, reaching the apex of the palatal root. The clinical diagnosis was an endodontic-periodontal lesion with primary periodontal disease. Subsequent endodontic treatment comprised pulp extirpation and root canal filling, followed by periodontal treatment consisting of scaling and root planing. The tooth was finally restored with a full metal crown. No further signs of periodontal disease or periapical lesions have been observed to date. Bacteria were sampled from the root canal and periodontal pocket for a microbiological assessment using 16S rRNA gene-based PCR. Microbiologically, the profile of the bacterial species from the palatal root canal was similar to that from the periodontal pocket of the palatal root. Porphyromonas gingivalis, Fusobacterium nucleatum and Eikenella corrodens were detected in both samples. The occurrence of bacteria common to both sites in this patient further supports the proposition that periodontal disease is the definitive source of root canal infections. The present results suggest that a bacterial examination would be helpful in confirming and supporting the clinical diagnosis in such lesions.

Accidental ingestion or aspiration of foreign objects at Tokyo Dental College Chiba Hospital over last 4 years.

The aim of this study was to investigate cases of accidental ingestion or aspiration occurring at Tokyo Dental College Chiba Hospital over the last 4 years in order to determine how the incidence of such events could be reduced. Forty cases of accidents occurring at our hospital over a 4-year period commencing in 2008 (representing 27% of the total number of accidents) included accidental ingestion in 39 patients and aspiration in one. Most of these accidents occurred during the removal or placement of restorations or prosthetics, and the ingested objects were mostly crowns and inlays. Accidental ingestion or aspiration occurred more frequently in the right molar region and when procedures were conducted by practitioners with less than 1 to 7 years of experience, and especially 1 to 3 years only. A higher rate of such accidents was observed in male patients in their 50s to 70s. The conventional safety procedures developed by the Medical Risk Management Team should be adhered to wherever possible. Furthermore, we propose the following measures based on the present results: accident prevention training for students and clinical trainees; improvement of the in-hospital manual; personal coaching for those breaching the guidelines of the safety manual; and raising awareness of the need for greater care in preventing incidents of accidental ingestion or aspiration at the Tokyo Dental College Chiba Hospital.

Digital video image processing from dental operating microscope in endodontic treatment.

Recently, optical microscopes have been used in endodontic treatment, as they offer advantages in terms of magnification, illumination, and documentation. Documentation is particularly important in presenting images to patients, and can take the form of both still images and motion video. Although high-quality still images can be obtained using a 35-mm film or CCD camera, the quality of still images produced by a video camera is significantly lower. The purpose of this study was to determine the potential of RegiStax in obtaining high-quality still images from a continuous video stream from an optical microscope. Video was captured continuously and sections with the highest luminosity chosen for frame alignment and stacking using the RegiStax program. The resulting stacked images were subjected to wavelet transformation. The results indicate that high-quality images with a large depth of field could be obtained using this method.

Character traits of malodor patients.

Many patients visit oral malodor clinics because of malodors which are brought to their attention by friends and family, or because they note the behavior of people around them, they suspect a problem and develop a fear of having an oral malodor. However, only around 30% of such patients actually have levels of malodor high enough to bother other people. Many patients exhibit halitophobia symptoms, which present as self-perception of malodor, and thus have a strong obsession about their smell which results in distress. Here, we carried out a study on 300 outpatients who visited the Tokyo Dental College Chiba Hospital Odor Clinic. We used the Tokyo University Egogram (TEG) to elucidate character traits of affected outpatients and compared the occurrence of TEG types in these patients with those of normal individuals. We discovered that 10.4% of patients were A-dominant type, which was 10.6% lower than the 21.0% of normal individuals. On the other hand, 18.4% of patients were N-type (NP high, FC low), which was 9.9% higher than the 8.5% of normal individuals. Results revealed that very few of the malodor outpatients exhibited the trait that shows intelligence, calm judgment, and self-affirmation, and as a result enjoy their life. Instead, many of these patients tended to show high levels of kindness and appeared to be holding themselves back and exercising patience.

Dens evaginatus on occlusal surface of maxillary second molar: a case report.

Dens evaginatus is a rare dental anomaly characterized by the development of a tubercle on the occlusal surface of the tooth and can cause pulpitis, pulp necrosis, and periapical periodontitis due to tubercular fracture or attrition. Unlike with caries, pain caused by dens evaginatus may manifest itself in a distant location. Therefore, diagnosing the cause of that pain may prove problematic. Dens evaginatus usually occurs in the mandibular premolars. We report a successfully treated case in which dens evaginatus was difficult to diagnose due to distant radiation of pulpitis-induced pain. This pain occurred as a result of fracture of a tubercle located on the occlusal surface of the maxillary second molar, which is very rare.

Survey of accidental ingestion and aspiration at Tokyo Dental College Chiba Hospital.

The occurrence of accidental ingestion/aspiration and preventive measures were investigated at Tokyo Dental College Chiba Hospital. In addition, the characteristics of accidents at our hospital were analyzed by surveying the awareness of accidental ingestion/aspiration to utilize the data for prevention. Accidental ingestion accounted for about 30% of accidents that occurred at our hospital in fiscal 2008, but all ingested items were naturally excreted, and no accidental aspiration occurred. Accidental ingestion most frequently occurred when dental restorations were removed. Inlays and crowns were most frequently ingested, and dentists with 5 to less than 10 years of clinical experience tended to be involved in these accidents. According to the results of the questionnaire, removal of restorations was perceived as the treatment least likely to cause accidental ingestion/aspiration. Moreover, dentists who always took preventive measures against accidental ingestion/aspiration accounted for only 40% or less on average. To avoid accidental ingestion/aspiration, repeated courses and individual instruction for repeaters and the establishment of a surveillance system along with manuals to manage the violation should be emphasized.

Clinical usefulness of "Isolite Plus" for oral environment of Japanese people.

The recent demand for dental devices which are easier to handle and offer higher levels of reliability and safety has led to the development in the US of Isolite Plus, a new oral support device. When placed in the oral cavity, Isolite Plus enables marking of the surgical field, secures the treatment space, ensures a vacuum, protects the cheek and tongue, assists in opening the mouth, prevents accidental ingestion/aspiration, ensures treatment without contamination and enhances comfort and safety during dental treatment. The present study was carried out to verify whether Isolite Plus can fit well in the mouth of Japanese people and to determine whether it performs adequately. Thirty resident dentists were required to wear Isolite Plus in their mouth and perform mutual simulation training using an air turbine handpiece. After the training, both subjects playing the role of surgeon and those playing the role of patient were asked to complete questionnaires. On the basis of the results, we discuss the clinical usefulness of Isolite Plus in Japanese people. In the present investigation, Isolite Plus was rated slightly better by surgeons than by patients. The supportive functions of the device were judged inadequate due to the poor fit of the mouthpiece portion of the device to subjects' mouth. For the distribution of Isolite Plus in the Japanese market, the mouthpiece portion of the device should be improved so that it can fit the mouth of Japanese people.

Clinical training in department of general dentistry at Tokyo Dental College Chiba Hospital.

A compulsory postgraduate clinical training program was established in April 2006 in Japan, and an applicants-only postgraduate training program 9 years ago at Tokyo Dental College. In addition, a training program was also established in the Department of General Dentistry at Tokyo Dental College Chiba Hospital in April 2002. The curriculum consists of training in the outpatient clinic and the following: 1) clinical training (preparation of written treatment plans, simulation practice, submission of evaluation sheets, and submission of training journals), 2) tutorials, and 3) case reports. In 1), trainees write treatment plans for new patients, discuss them with their instructor, perform simulation practice using dummies based on those discussions, submit evaluation sheets and training journals concerning treatment, and receive their instructor's assessment. In 2), trainees are divided into small groups, independently study themes they have chosen, and present the results. In 3), they orally report cases they have treated and receive evaluation by other trainees and instructors in general discussion meetings. In addition, a course was also established at the Department of General Dentistry, Tokyo Dental College Chiba Hospital in April 2002. We report the training curriculum of this course.

Tissue reactions after intraosseous implantation of three retrofilling materials.

Bone tissue reactions to EBA, IRM, and cyanoacrylate cement (Base Liner) were studied in the rat mandible using an intraosseous implant method. Osseous cavities (1.4 mm in diameter) were surgically created in the mandibles, and materials were implanted in 60 male Wistar rats. Each specimen was evaluated histologically after 4 and 8 weeks. The development of fibrous connective tissue in direct apposition to the material was observed in the EBA and IRM groups at 4 weeks. A slight degree of macrophage infiltration was seen in the EBA group. After the 8-week observation period, IRM and EBA were frequently separated from the bone cavity by a fibrous connective tissue layer (p < 0.01). The Base Liner appeared to be in direct apposition to the osseous tissue in several areas (p < 0.01). These findings indicate that Base Liner reacts favorably with osseous tissue, compared with the EBA and IRM materials tested and seems to be a biocompatible material.