Bulletin of Tokyo Dental College最新文献

Many cases of immunoglobulin G4-related disease (IgG4-RD) involve swelling of the salivary glands, often affecting the parotid and submandibular glands in the head and neck region, in addition to the lacrimal glands. Cases of IgG4-RD characterized by swelling of the palatal glands, however, are extremely rare. Here, we describe a case of IgG4-RD involving bilateral swelling of the palatal glands. An 83-year-old man presented at our hospital with bilateral swelling of the lacrimal and submandibular glands. A solid bilateral swelling of normal colour and unclear boundaries was observed in the hard palate. The lesion was diagnosed as IgG4-RD and steroid therapy initiated. A subsequent decrease in swelling of the palatal, lacrimal, and submandibular glands was confirmed by magnetic resonance imaging. These results indicate that dentists should suspect IgG4-RD in patients presenting with bilateral swelling of the palatal glands.

A range of experimental designs have been used in destructive testing of composite resin CAD/CAM crowns. Various materials have been adopted for the abutment in such tests, including human or bovine dentin, stainless steel, PMMA, and composite resin, the selection of which is made in accordance with study objective or preference of the researcher. The purpose of this study was to determine how the material selected for the abutment material affected fracture load and maximum displacement. Destructive tests were conducted on composite resin crowns of the same design. Three types of material were used for the abutments together with 2 types of adhesive material. Images of each sample were acquired before destruction using a microfocus X-ray CT scanner to confirm the feasibility of a non-destructive test.The load required to fracture the composite CAD/CAM resin crowns depended on the abutment material used, with a decrease being observed in the order of composite resin, stainless steel, and PMMA. Maximum displacement decreased in the order of PMMA, composite resin, and stainless steel. Differences in the material used for setting (adhesive resin or polycarboxylate cement) showed no effect on fracture load. These results indicate that the load required to achieve destruction of resin CAD/CAM crowns varies according to the abutment material used.

Candida albicans is the primary candidiasis-causing fungal pathogen in humans, and one of its most important virulence factors is the ability to form biofilms. Moreover, these biofilms are often resistant to antifungal agents, so there is a need to develop alternative elimination strategies and therapeutic agents for such infections. The antifungal activity of resveratrol, a phytoalexin polyphenolic compound, impairs the morphological transition of C. albicans under various hypha-inducing conditions and inhibits growth of the yeast-form and mycelia. The purpose of this study was to investigate the effect of resveratrol against C. albicans biofilm formation. The developmental, sustained, and mature stages of biofilm formation were affected or inhibited by resveratrol. Exposure to resveratrol at the developmental stage inhibited growth of C. albicans in a dose-dependent manner. A >30% reduction was observed in sustained biofilm growth in the presence of 200 μg/ml resveratrol in comparison with in its absence. In terms of disruption of matured biofilm, 6.25-100 μg/ml resveratrol significantly reduced cell viability of C. albicans compared with in a control sample (p<0.05). The present results indicate that resveratrol has the potential to serve as an anti-Candida treatment and preventive tool which functions by inhibiting existing or under-forming C. albicans biofilms.

An ameloblastic fibroma (AF) is a proliferative mixed tumor which includes components of both odontogenic epithelium and mesenchymal tissue. It is a relatively rare neoplasm, accounting for approximately only 1.5－4.5% of odontogenic tumors. This case report describes an AF that occurred in the mandibular anterior tooth region in a 9-year-old girl who presented with the chief complaint of swelling in the left mandibular anterior tooth region. Intraoral examination revealed a swelling along the labial gingiva, extending from the left mandibular lateral incisor region to the left mandibular canine. Upon palpation, the swelling appeared to comprise a hard tissue. Computed tomography revealed a supernumerary impacted tooth; soft tissue density in the bone surrounding the region extending from the left mandibular lateral incisor to the left mandibular canine; labial bone expansion; and thinning of the labial cortical bone. A biopsy was performed under local anesthesia and the lesion subsequently diagnosed as an AF. Tumor resection and extraction of the supernumerary impacted tooth were carried out under general anesthesia. At 2 years postoperatively the prognosis is good. Although relapse with an AF is rarer than that with an ameloblastoma, strict follow-up is required, as malignant transformation to an ameloblastic fibrosarcoma has been reported in relapsed cases.

The purpose of the present study was to clarify the long-term effects of frequent chewing of unflavored and odorless gum (hereafter, gum base) on oral hygiene and mental health. This single-arm study, which started with a 4-week control and ended with a 4-week intervention period, was conducted in two phases: one in 2017 and one in 2018. The participants comprised 36 dental hygiene students (17 in 2017, 19 in 2018). During the intervention period, all participants were required to chew a piece of gum base 7 times a day for 10 min each time. The unstimulated salivary flow rate and masticatory efficiency were measured and chewing number counted. Two questionnaires －the Profile of Mood States, second edition (POMS2) and the 30-item General Health Questionnaire (GHQ-30)－ were administered to assess mental health. In both phases, the unstimulated salivary flow rate showed a significant increase after the intervention period (p<0.05). In 2017, the GHQ-30 scores and masticatory efficiency showed a tendency toward a negative correlation after the intervention period (r=－0.4647, p=0.06). In 2018, a significant negative correlation was observed between chewing number and the POMS2 scores after the intervention period (r=－0.6296, p<0.01). These findings suggest that frequent chewing of gum base increases unstimulated salivary flow rate. However, no significant change was observed in the mental health.

Aggressive periodontitis during adolescence has a poor prognosis due to rapid alveolar bone resorption. Few studies have investigated long-term follow-up after surgical orthodontic treatment performed in conjunction with that for invasive periodontitis. Here, we report a case of mandibular prognathism accompanied by generalized aggressive periodontitis and crowding. A 31-year-old woman was referred to our department for treatment of masticatory dysfunction due to reverse overjet. The patient exhibited a class III molar relationship, protrusion of the ANB of －6.0°, and severe maxillary crowding. Initial periodontal examination revealed deep periodontal pockets and extensive inflammation. Mandibular prognathism accompanied by generalized aggressive periodontitis and crowding was diagnosed. Therefore, it was necessary to adopt an interdisciplinary approach involving surgical, orthodontic, and periodontal treatment. Prior to commencement of orthodontic treatment, plaque control, scaling, and root planing of all teeth were performed by a periodontist to suppress inflammation and reduce probing depth. During pre-surgical orthodontic treatment, the maxillary first premolars were extracted to reduce crowding of the maxillary incisors. To correct the mandibular prognathism, the mandible was repositioned by sagittal split ramus osteotomy. Proper occlusion of the incisors and maximum intercuspation were achieved by post-surgical orthodontic treatment. After completion of active orthodontic treatment, acceleration of inflammation was observed together with aggravated resorption of the alveolar bone surrounding the molars. However, reduction of probing depth and inflammation were observed after scaling and root planing. The surgical-orthodontic treatment time was 1 year and 11 months, which was followed by a 2-year retention period. There was no tooth loss due to periodontitis, and an overall satisfactory outcome was achieved.

This report describes a patient with severe high angle class II malocclusion and mandibular retrusion in whom surgical orthodontic treatment to prevent an increase in ramus height resulted in a significant improvement in esthetics and long-term stability. The patient was a woman aged 30 years 5 months who presented with the chief complaint of maxillary protrusion. She had a convex facial type, a chin button on lip sealing, and a gummy smile. Cephalometric analysis revealed a normal maxilla anterior-posterior position, but significant mandibular retrusion with pronounced clockwise rotation. The anterior maxillary tooth axis was standard, but labially inclined in the mandible. Based on these findings, the diagnosis was skeletal class II high angle malocclusion and mandibular retrusion. The proposed treatment plan comprised 2-jaw surgery with premolar extraction. Le Fort I osteotomy, in particular, was planned in the maxilla to move the ANS upward by 3.0 mm and the PNS downward by 3.0 mm. Sagittal split ramus osteotomy (SSRO) was planned to adjust the mandible and move the mandible forward by 10.0 mm. To prevent postoperative relapse, the short lingual split method was used in performing the SSRO. The mandible was split to minimize stretching of the median pterygoid muscle. Postoperatively, the ANS, PNS, and pogonion showed movement of 2.0 mm upward, 3.0 mm downward, and 8.0 mm forward, respectively. Additionally, lip closure was now natural, and the gummy smile had markedly improved. At 6 years postoperatively, there has been no change skeletally or dentally. Follow-up is being continued to monitor further progress.

Here, we report a case of generalized chronic periodontitis with furcation involvement that was treated successfully by means of surgical intervention. The patient was a 43-year-old man requesting treatment for periodontal disease. An initial examination revealed 42% of sites with a probing depth of ≥4 mm and 42.9% of sites with bleeding on probing. The maxillary molars showed varying degrees of furcation involvement. Radiographic examination revealed bone resorption in the molar and mandibular anterior teeth regions. Microbiological examination of subgingival plaque revealed the presence of Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, and Tannerella forsythia. The patient's oral health-related quality of life (OHRQL) was also assessed. Based on a clinical diagnosis of severe chronic periodontitis, initial periodontal therapy was performed. Plaque control, scaling and root planing, extraction, temporary fixed restoration, occlusal adjustment, and root canal treatment were implemented. Following reevaluation, open flap debridement was performed at selected sites. Root resection was performed on the distal root of #16. Prosthetic treatment was then initiated for recovery of oral function. After confirmation of appropriate occlusion and cleanability, the patient was placed on supportive periodontal therapy. Root resection improved cleanability. This clinical improvement has been adequately maintained over a 2-year period. The patient's OHRQL score showed a slight deterioration during the supportive periodontal therapy OK period, however. This indicates the need for further careful monitoring of periodontal conditions, as well as of how they are perceived by the patient themselves.

This case report describes the unusual choice of extraction of maxillary incisors with short roots as part of an orthodontic treatment plan. The patient was a 20-year-old woman referred to our department in whom the diagnosis was maxillary protrusion and open bite. Both of the maxillary central incisors had short roots. Two treatment options were considered. The first involved extraction of the 4 first premolars with the aim of improving dentoalveolar protrusion and crowding. If preservation of the central incisors subsequently became difficult due to root resorption, prosthetic options were to be considered. The second treatment option involved extraction of the maxillary central incisors with short roots and the mandibular first premolars. The second treatment option was selected as survival of the central incisors following orthodontic movement was uncertain and the patient also wanted to minimize the risk of future extractions and the use of prosthetics. Active treatment was performed over a span of 31 months, and circumferential type retainers were used on both arches for retention. For such treatment to be successful, careful diagnosis and orthodontic treatment planning must be taken to ensure the anterior dental esthetics are properly restored.

Clinical use of 0.3% recombinant human fibroblast growth factor (rhFGF)-2 for periodontal regeneration received formal approval in Japan in 2016. The combination of growth factor and bone graft material is used to enhance periodontal healing in regenerative therapy. The exact effects of combination therapy on periodontal healing remain unknown, however. Here, we report three cases of chronic periodontitis treated with the combination of rhFGF-2 and deproteinized bovine bone mineral (DBBM). Following initial periodontal therapy, periodontal regenerative therapy using rhFGF-2 in combination with DBBM was performed to treat wide intrabony defects. Periodontal parameters and radiographic bone fill were reevaluated at 3 months, 6 months, and 1 year postoperatively. Oral health-related quality of life (OHRQL) was assessed as a patient-reported measure of outcome. At 1 year postoperatively, probing pocket depth and clinical attachment level showed a significant improvement in comparison with at baseline. An improvement was also noted in radiographic evidence of bone fill and total OHRQL scores. Combination therapy yielded clinically favorable results in the present cases.