Denture stabilizers are available on the retail market and often used by denture wearers to improve the function of an ill-fitting denture. They can be broadly divided into denture adhesives, available in cream, powder, and sheet （tape） forms, and home reliners, which are in cushion form. Although denture stabilizers were initially considered to have negligible effects, the usefulness of denture adhesives has been increasingly recognized by researchers in recent years. In those studies, cream and powder types have been shown to be useful adjuncts for denture maintenance and denture prosthesis applications when used in a correct manner under suitable conditions. However, harmful effects caused by improper use are often found in patients. Therefore, it is important for dentists to acquire proper knowledge regarding denture adhesives and their correct application in order to take advantage of the materials and prevent incorrect use.

Since 1970ʼs, application of a cast post system commenced in Japan, which enabled conservation of teeth that had previously been diagnosed the need for extraction. Since it was integrated into Japanese health insurance system in 1985, the number of these treatments has been multiplying, and it had been expected that there would continue to be an increase in the occurrence of root fractures. Investigation of etiology of permanent tooth loss by 8020 Promotion Foundation in 2005 reported that 11％ of tooth loss was due to root fractures. 4-META/MMATBB resin cement was developed in Japan in 1982, having high bond strength and excellent biocompatibility. This material was applied to adhesive treatment of vertical root fractures in the same year and has been demonstrating favorable result. This article focuses on development and evidence-based background of vertical root fracture adhesive treatment.

This case report introduces diagnosis and treatment methods of temporomandibular disorder using a soft splint. Temporomandibular disorder, or TMD can be triggered by vari-ous combinations of systemic and psychological causes beyond the physiological capacity. Although occlusion–related factors are considered to be one of the greatest causes in a number of cases, the causal relationship between TMD and occlusion is still controversial due to the shortage of scientific evidence. There is no clear consensus on the diagnosis and treatment among clinicians; many of them are unsure whether they should inter-vene with the occlusion, and if so, how they should deliver the treatment. Therefore, we suggest to firstly examine to what extent occlusal causes are factors and to then conduct treatment to the relevant factors when dental causes are observed partially or totally, and occlusal factors do not require urgent intervention. The authors utilise a soft splint, which prevents dental contact in occlusion, in order to deliver a differential diagnosis and treatment for dental causes in cases with various TMD symptoms. Many clinical cas-es have resulted positively by adjusting the splint according to symptom observations, such as mouth opening width, mouth opening and closing trajectory, and provoked pain on muscle palpation, which is presumably an accompanying symptom of TMD and jaw pain during mandibular movement.

In the current trends, anatomical, traumatic, occlusal, behavioral, and psychological factors are considered as the cause(s) of TMJ disorder; Some events such as trauma or stress happen and when they exceed a certain threshold of physiological tolerance, TMJ disorder may be manifested. Reversible interventions such as functional training (rehabilitation) and splint therapy are considered as primary treatment options and often prioritized. These remedies are, however, symptomatic treatments. Hence in dental practice, first, differential diagnosis―whether the symptom is occlusion related―need be made, and if so, etiotropic treatment on the occlusion needs to be applied. In the present paper discussed is a case of temporomandibular joint dysfunction (TMD criteria group IIIb: osteoarthritis of the TMJ), suspectedly due to occlusal factors. Splint therapy to stabilize the masseter muscles and the TMJ proved effective in improving mandibular function; and subsequent occlusal reconstruction with reference to the condyle position in X-ray images was also successful in improving the patientʼs chief-complain, namely, symptoms of the TMJ and chewing dysfunction.

Due to change in living circumstances, sanitary conditions, diet, quality of water, soil- and air-environment, increase of allergy patients has become a societal issue in the developed countries, including our country. The allergic reaction is an excessive immunoreaction to certain antigenic agents and a necessary physiological function to keep foreign bodies (antigens) away. Among various causes and pathogeneses of allergies, metal allergies related to dental treatment (iatrogenic) have attracted attention in recent years. While prosthetic materials in dentistry have been shifting to the non-metal, there still remain many patients with dental-related allergosis due to the long history of metal-material dependent restorations. Presented in this report is a case of a patient with ongoing systemic dermatitis, diagnosed as metallic allergy with patch skin test by a dermatologist in university hospital. Intraoral findings included metal restorations in multiple teeth. The patientʼs dermatological symptom was observed by the dermatologist in conjunction with dental treatment replacing metal restorations. About one year from the onset of treatment, improvement of the skin condition was observed, and prosthetic treatment also resulted in recovery of occlusal function.

The purpose of the present study was to examine the influence of medical history of periodontal disease on the outcomes of treatment with implants with modified titanium surfaces. Placed in 124 patients were a total of 425 implants with titanium surfaces modified by wire electrical discharge machining. Of those patients selected were the patients whose implant superstructures had stayed in place for 8-20 years; the subjects were then divided into two groups, with (Group A) and without medical history of periodontal disease (Group B) according to the alternative method described by Hardt et al. The clinical courses of the implant treatment provided to each group were evaluated. The group with medical history included 41 patients with a total of 154 implants. The mean observation period was 13.8 years in Group A, and the number of implants that were removed during the observation period was 15 (9.7％). Additionally, bone resorption of more than 3 mm in the mesial and distal sites of the peri-implant marginal bone was observed in 13 implants (8.4％) although the bodies had not been removed. On the other hand, Group B included 41 patients with a total of 129 implants, and the mean observation period was 14.1 years. Four implants (3.1％) were removed during the observation period. Additionally, bone resorption of more than 3 mm in the mesial and distal sites of the periimplant marginal bone was observed in 3 implants (2.3％) although the bodies had not been removed. Consequently, Group A presented an implant survival rate of 90.3％ and a success rate of 81.8％ while in Group B the survival rate and success rate were 96.8％ and 94.6％, respectively. Thus, there were significant differences in the survival rate and the success rate between the two groups. Additionally, the removal of implants and the bone resorption in the peri-implant-neck marginal sites without causing implant removal occurred more frequently in Group A.