Metal allergy patient treated by titanium implant denture: A case report with at least 4-year follow-up

Patch testing with metal reagents was positive on female patient with history of metal hypersensitivity after dental treatment. All of the dental restorations with metal components were removed, and subsequent oral rehabilitation utilizing dental implants and metal-free prostheses was carried out. The treatments alleviate the presenting signs and symptoms.

Posterior disc displacement of the temporomandibular joint: A rare case report

BACKGROUND

Posterior disc displacement (PDD) of the temporomandibular joint (TMJ) is quite rare. The normal position of a disc is slightly anterior to the condyle, so the chances of disc displacement to the posterior direction are low.

CASE PRESENTATION

A 71-year-old Japanese female reported with a chief complaint of lack of occlusion on the right-side molar teeth. Clinical examination revealed lack of occlusal contact in the right posterior region, nearly normal range of mouth opening (41.0 mm), masseter muscle tenderness, and deviation to the left on opening. MRI of the right TMJ showed PDD in both the open- and closed-mouth position and joint effusion. Conservative treatment with a non-steroidal anti-inflammatory drug, stretch exercise with fingers, and stabilization splint improved symptoms for 9 months.

CONCLUSION

Conservative treatment was effective in managing the patient. A follow-up for 9 months with a repeat MRI was undertaken to monitor the progress.

Educational effects using a robot patient simulation system for development of clinical attitude

INTRODUCTION

The aim of this study was to assess the effectiveness of improving the attitude of dental students towards the use of a full-body patient simulation system (SIMROID) compared to the traditional mannequin (CLINSIM) for dental clinical education.

MATERIALS AND METHODS

The participants were 10 male undergraduate dental students who had finished clinical training in the university hospital 1 year before this study started. They performed a crown preparation on an upper pre-molar tooth using SIMROID and CLINSIM as the practical clinical trials. The elapsed time for preparation was recorded. The taper of the abutment teeth was measured using a 3-dimensional shape-measuring device after this trial. In addition, a self-reported questionnaire was collected that included physical pain, treatment safety and maintaining a clean area for each simulator. Qualitative data analysis of a free format report about SIMROID was performed using text mining analysis. This trial was performed twice at 1-month intervals.

RESULTS

The students considered physical pain, treatment safety and a clean area for SIMROID significantly better than that for CLINSIM (P < .01). The elapsed time of preparation in the second practical clinical trial was significantly lower than in the first for SIMROID and CLINSIM (P < .01). However, there were no significant differences between the abutment tapers for both systems. For the text mining analysis, most of the students wrote that SIMROID was similar to real patients.

CONCLUSION

The use of SIMROID was proven to be effective in improving the attitude of students towards patients, thereby giving importance to considerations for actual patients during dental treatment.

Cross-sectional observational study exploring clinical risk of titanium allergy caused by dental implants

PURPOSE

Studies have reported cases of metal allergy caused by titanium-containing materials. We wished to clarify the relationship between titanium allergy and dental implants by describing patients who suffered allergic symptoms after they had received such implants.

METHODS

A total of 270 patients who visited a Dental Metal Allergy Clinic at Tokushima University Hospital from April 2010 to March 2014 were the study cohort. Patch testing with 28 types of metal allergens (including four titanium allergens) was undertaken for patients.

RESULTS

A total of 217 patients (80.4 %) exhibited allergy-positive reactions to at least one type of metal allergen. Mercury, palladium, chromium and nickel exhibited a higher prevalence of allergy-positive reactions than other metals. Sixteen patients visited our clinic suffering allergic symptoms after receiving dental implants. Eleven of those patients exhibited allergy-positive reactions for any of the metal allergens, and 4 of these patients had allergy-positive reactions against titanium allergens. The total number of allergy-positive reactions for titanium allergens among all 270 patients was 17 (6.3 %). No patient exhibited a positive reaction only for the titanium allergen.

CONCLUSIONS

The prevalence of allergy-positive reactions for titanium allergens was lower than for other metal allergens. We suggest examination of pre-implant patients who have a history of hypersensitivity reactions to metals.

Validity of Peer Evaluation for Team-Based Learning in a Dental School in Japan

The aim of this study was to determine the validity of peer evaluation for team-based learning (TBL) classes in dental education in comparison with the term-end examination records and TBL class scores. Examination and TBL class records of 256 third- and fourth-year dental students in six fixed prosthodontics courses from 2013 to 2015 in one dental school in Japan were investigated. Results of the term-end examination during those courses, individual readiness assurance test (IRAT), group readiness assurance test (GRAT), group assignment projects (GAP), and peer evaluation of group members in TBL classes were collected. Significant positive correlations were found between all combinations of peer evaluation, IRAT, and term-end examination. Individual scores also showed a positive correlation with group score (total of GRAT and GAP). From the investigation of the correlations in the six courses, significant positive correlations between peer evaluation and individual score were found in four of the six courses. In this study, peer evaluation seemed to be a valid index for learning performance in TBL classes. To verify the effectiveness of peer evaluation, all students have to realize the significance of scoring the team member's performance. Clear criteria and detailed instruction for appropriate evaluation are also required.

Comparison between flipped classroom and team-based learning in fixed prosthodontic education

PURPOSE

We previously investigated the effects of team-based learning (TBL) on fixed prosthodontic education and reported that TBL could have higher efficiency with high student satisfaction than traditional lecture. In the current report, we introduced flipped classroom to the fixed prosthodontic education and compared their effectiveness based on the final examination score in addition to TBL.

METHODS

Participants were 41 students from Tokushima University School of Dentistry who attended a fixed prosthodontics course. The first six classes adopted the flipped classroom style while the latter eight classes adopted TBL. To evaluate the relationship between learning styles and their effectiveness, we compared results from the term-end examination between the curriculum covered by flipped classroom and TBL-style classes. To draw comparisons, a referential examination with the same questions was conducted to eight faculty members who had not attended any of these classes.

RESULTS

Term-end examination results showed that TBL classes had slightly higher scores than flipped classroom classes. Referential examination results also showed higher scores for the same curriculum and no significant interaction was found between class formats and the term-end and referential examination scores. Analysis revealed no noticeable difference in the effectiveness of the class formats.

CONCLUSION

Our previous study reported that TBL had higher efficiency than traditional style lecture. In the current study, there was no statistical difference in the examination score between flipped classroom and TBL. Therefore, we conclude that both styles are highly effective than traditional style lecture and constitute valid formats for clinical dental education.

Allergic contact dermatitis caused by titanium screws and dental implants

PATIENTS

Titanium has been considered to be a non-allergenic material. However, several studies have reported cases of metal allergy caused by titanium-containing materials. We describe a 69-year-old male for whom significant pathologic findings around dental implants had never been observed. He exhibited allergic symptoms (eczema) after orthopedic surgery. The titanium screws used in the orthopedic surgery that he underwent were removed 1 year later, but the eczema remained. After removal of dental implants, the eczema disappeared completely.

DISCUSSION

Titanium is used not only for medical applications such as plastic surgery and/or dental implants, but also for paints, white pigments, photocatalysts, and various types of everyday goods. Most of the usage of titanium is in the form of titanium dioxide. This rapid expansion of titanium-containing products has increased percutaneous and permucosal exposure of titanium to the population.

CONCLUSIONS

In general, allergic risk of titanium material is smaller than that of other metal materials. However, we suggest that pre-implant patients should be asked about a history of hypersensitivity reactions to metals, and patch testing should be recommended to patients who have experienced such reactions.

Masticatory performance alters stress relief effect of gum chewing

PURPOSE

We evaluated the effects of gum chewing on the response to psychological stress induced by a calculation task and investigated the relationship between this response and masticatory performance.

METHODS

Nineteen healthy adult volunteers without dental problems undertook the Uchida-Kraepelin (UK) test (30 min of reiterating additions of one-digit numbers). Before and immediately after the test, saliva samples were collected from the sublingual area of the participants. Three min after the UK test, the participants were made to chew flavorless gum for 3 min, and the final saliva samples were collected 10 min after the UK test. The experiment was performed without gum chewing on a different day. Masticatory performance was evaluated using color-changing chewing gum.

RESULTS

Salivary CgA levels at immediately and 10 min after the UK test were compared with and without gum chewing condition. Two-way repeated measures analysis of variance revealed significant interaction between gum chewing condition and changes in CgA levels during post 10 min UK test period. A significant correlation was found between changes in CgA levels and masticatory performance in all participants.

CONCLUSION

Our results indicate that gum chewing may relieve stress responses; however, high masticatory performance is required to achieve this effect.

Cross-Excitation in Peripheral Sensory Ganglia Associated with Pain Transmission

Despite the absence of synaptic contacts, cross-excitation of neurons in sensory ganglia during signal transmission is considered to be chemically mediated and appears increased in chronic pain states. In this study, we modulated neurotransmitter release in sensory neurons by direct application of type A botulinum neurotoxin (BoNT/A) to sensory ganglia in an animal model of neuropathic pain and evaluated the effect of this treatment on nocifensive. Unilateral sciatic nerve entrapment (SNE) reduced the ipsilateral hindpaw withdrawal threshold to mechanical stimulation and reduced hindpaw withdrawal latency to thermal stimulation. Direct application of BoNT/A to the ipsilateral L4 dorsal root ganglion (DRG) was localized in the cell bodies of the DRG and reversed the SNE-induced decreases in withdrawal thresholds within 2 days of BoNT/A administration. Results from this study suggest that neurotransmitter release within sensory ganglia is involved in the regulation of pain-related signal transmission.

Diagnosis and treatment for obstructive sleep apnea: Fundamental and clinical knowledge in obstructive sleep apnea

PURPOSE

This review article covers the diagnosis and treatment of obstructive sleep apnea (OSA) from a dental perspective. It addresses the issue of when and how to screen for and then, if indicated, refer the patient for a more comprehensive.

STUDY SELECTION

Our focus in this article was on identifying current unanswered questions that relevant to OSA problems that dental scientists have to pursue and on providing valuable information on that problems, consequently the previous studies which investigated or reviewed the diagnosis and treatment of OSA were included. In addition, we included studies on jaw movements during sleep and on the use of a lateral cephalometric film related to the diagnosis and treatment of OSA.

RESULTS

The role of portable sleep monitoring devices versus full laboratory polysomnography is discussed. This review also describes what is known about the efficacy of mandibular advancement devices and when and how they fit in to a treatment program for a patient with obstructive sleep apnea. Finally some basic research is presented on jaw movements during sleep and how a lateral cephalometric film can be used to assess the changes of the airway with body posture and head posture.

CONCLUSION

This article provides the valuable suggestions for the clinical questions in the diagnosis and treatment of OSA.

Effects of team-based learning on fixed prosthodontic education in a Japanese School of Dentistry

The aims of this study were to evaluate the quality of team-based learning (TBL) in prosthodontics education for fourth-year dental students at Tokushima University School of Dentistry and to compare this teaching method with traditional lecture-based delivery. Participants in the study were 36 students (22 males and 14 females) who attended the TBL-style fixed prosthodontics course. Ten 60-minute classes were held. The first three were traditional lecture-style classes and were followed by one class introducing the TBL style. The remaining six classes constituted the TBL-format fixed prosthodontics course. The effectiveness of TBL was evaluated through student questionnaires at the end of each class and the results of the term-end examination. The questionnaire revealed high student approval for TBL-style learning, and active group discussion among students during TBL was a key factor in these ratings. In the results of the term-end examination, there were significantly higher scores on the questions that covered TBL-taught material than those covering traditional lecture-taught topics. The results of this study suggest that TBL-style lecture was more effective than traditional-style lecture for teaching fixed prosthodontics and that TBL was a more efficient mode of delivering dental education than traditional lecture-based teaching.

A proposed core curriculum for dental English education in Japan

BACKGROUND

Globalization of the professions has become a necessity among schools and universities across the world. It has affected the medical and dental professions in terms of curriculum design and student and patient needs. In Japan, where medicine and dentistry are taught mainly in the Japanese language, profession-based courses in English, known as Medical English and Dental English, have been integrated into the existing curriculum among its 83 medical and 29 dental schools. Unfortunately, there is neither a core curriculum nor a model syllabus for these courses.

METHODS

This report is based on a survey, two discussion forums, a workshop, and finally, the drafting of a proposed core curriculum for dental English approved by consensus of the participants from each university.

RESULTS

The core curriculum covers the theoretical aspects, including dental English terms and oral pathologies; and practical aspects, including blended learning and dentist-patient communication. It is divided into modules and is recommended to be offered for at least two semesters.

CONCLUSIONS

The core curriculum is expected to guide curriculum developers in schools where dental English courses are yet to be offered or are still in their early development. It may also serve as a model curriculum to medical and dental schools in countries in Asia, Europe, Africa, and Central and South America, where English is not the medium of instruction.

Systematic review and recommendations for nonodontogenic toothache

Nonodontogenic toothache is a painful condition that occurs in the absence of a clinically evident cause in the teeth or periodontal tissues. The purpose of this review is to improve the accuracy of diagnosis and the quality of dental treatment regarding nonodontogenic toothache. Electronic databases were searched to gather scientific evidence regarding related primary disorders and the management of nonodontogenic toothache. We evaluated the level of available evidence in scientific literature. There are a number of possible causes of nonodontogenic toothache and they should be treated. Nonodontogenic toothache can be categorised into eight groups according to primary disorders as follows: 1) myofascial pain referred to tooth/teeth, 2) neuropathic toothache, 3) idiopathic toothache, 4) neurovascular toothache, 5) sinus pain referred to tooth/teeth, 6) cardiac pain referred to tooth/teeth, 7) psychogenic toothache or toothache of psychosocial origin and 8) toothache caused by various other disorders. We concluded that unnecessary dental treatment should be avoided.

Clinical application of removable partial dentures using thermoplastic resin. Part II: Material properties and clinical features of non-metal clasp dentures

This position paper reviews physical and mechanical properties of thermoplastic resin used for non-metal clasp dentures, and describes feature of each thermoplastic resin in clinical application of non-metal clasp dentures and complications based on clinical experience of expert panels. Since products of thermoplastic resin have great variability in physical and mechanical properties, clinicians should utilize them with careful consideration of the specific properties of each product. In general, thermoplastic resin has lower color-stability and higher risk for fracture than polymethyl methacrylate. Additionally, the surface of thermoplastic resin becomes roughened more easily than polymethyl methacrylate. Studies related to material properties of thermoplastic resin, treatment efficacy and follow-up are insufficient to provide definitive conclusions at this time. Therefore, this position paper should be revised based on future studies and a clinical guideline should be provided.