Fixed dental prosthesis is one of the treatment methods for patients with missing teeth to restore oral functions and aesthetics. The purpose of this study was to compare the survival and success rates of bridge treatment in patients with the same number of missing teeth at the outpatient denture clinic of Iwate Medical University Dental Center, and to help obtain a long-term prognosis for prosthetic treatment.

The subjects were 332 patients who underwent three-unit fixed dental prosthesis treatment at the current Iwate Medical University Dental Center denture outpatient clinic over a period of about four years from April 1, 2011 to December 31, 2014, when patient information was available. The cumulative success rate of the entire bridge was 88.1%, and the survival rate was 92.3%.

The cumulative success rate and survival rate of adhesive bridges were 71.4% and 78.6%, respectively, which were lower than those of conventional and extended fixed prosthetic denture. Among the complications, all of the abutment teeth of root fracture were inactive.

The results suggest that the use of metal cores for abutment teeth may be one of the factors that cause fracture. It was inferred that the risk of root fracture may be lower if metal-free treatment is chosen when posts are used.

We report a case of systemic AL amyloidosis complicated by multiple oral masses in a patient with Waldenström macroglobulinemia. A 65-year-old man was referred to our department for comprehensive evaluation of multiple intraoral masses. He reported a history of WM in 2002 and received chemotherapy. In 2012, he developed a skin nodule and was diagnosed with amyloidosis. Intraoral examination revealed a mass （25 × 20 × 15 mm） involving the anterior mandibular vestibule and several masses （each approximately the size of a soy bean） in the bilateral premolar areas. A separate mass （20 × 15 × 5 mm） was observed on the mid-dorsum of the tongue and another mass （30 × 15 × 10 mm） on the ventral aspect of the tongue. These masses appeared yellowish in color and were elastic hard with clear borders and smooth overlying mucosa. Biopsy of each mass revealed amyloidosis, and he was diagnosed as AL kappa type by histochemical methods, and the final diagnosis of systemic AL amyloidosis associated with Waldenström macroglobulinemia was made. The patient refused resection of the oral masses and only underwent follow-up. Subsequently, he received chemotherapy over 2 years at the department of hematology; however, progressive gastrointestinal amyloidosis led to malabsorption and nutritional imbalance with deterioration in his general condition, and he died in May 2016.

Displacement of tooth is one of incidents in tooth extraction. We report a case of wisdom tooth displaced into oral floor and removed using an endoscope under general anesthesia at a later date. A 32-years-old man referred to our institution for extraction of bilateral mandibular wisdom teeth. Bone defect was detected at the lingual cortical bone around the left mandibular wisdom tooth by preoperative dental corn-beam CT. At the time of extraction of the left mandibular wisdom tooth, the tooth was divided into several pieces and the extraction was carefully performed, but a part of the tooth root displaced into the floor of the mouth. The displaced tooth was detected at the lingual side of mandibular by dental corn-beam CT. Since it was expected that direct vision of the displaced tooth would be difficult, the removal was performed using an endoscope under general anesthesia at a later date. After the operation, there were no adverse events such as lingual nerve injury due to surgery, and the course was good.

Down syndrome is the most frequent chromosomal abnormality that survives in humans. It occurs with excessive replication of all or required areas （Down syndrome critical region） of chromosome 21.

Since this case has Down syndrome, severe intellectual disability and schizophrenia, and dental treatment is difficult even after training, it was decided to perform dental treatment by pharmacological method.

With regard to pharmacological behavioral adjustment, deep sedation was selected because pulmonary shading had been observed for three years but there had been no change recently, and since the response to the preoperative inquiry, examination of the airway, and human and equipment conditions were in place.

At the time of introduction, abnormal breathing and mild decrease in SpO2 were observed during the excitement phase, but it was improved by auxiliary ventilation. Accidental ingestion and aspiration in deep sedation is thought to be caused by suction of water injection or saliva or by suction of cutting pieces. During surgery, aspiration prevention measures were taken, and in addition to the usual dental vacuum, suction catheters that easily sucked the pharynx were used as appropriate. During the operation, measures were taken to prevent aspiration, and in addition to the usual dental vacuum, a suction catheter that easily sucks water from the pharynx was used as needed. In addition, the amount of water injected during dental treatment was adjusted so as not to be large, and rubber dams were attached when resin was repaired, and cutting pieces and inflow into the pharynx and larynx were prevented by preventing irritation. Intraoperative vital signs and auscultatory findings were normal. Chest X-ray and auscultation were performed immediately after the operation, and the patient was able to complete the dental treatment under deep sedation without any change in his general condition. After returning home, no symptoms of upper respiratory tract infection such as fever and cough were observed.

Fanconi Anemia （FA） is a congenital bone marrow failure syndrome that causes pancytopenia. In dental procedures, it may be necessary to consider blood transfusion based on the prediction of the amount of bleeding. In addition, the frequency of leukemia and solid tumors is high, and this tendency is particularly strong in the oral cavity. Therefore, it is important to regularly scrutinize the presence or absence of oral tumors. In addition, since it is highly sensitive to radiation, it is necessary to avoid X-ray imaging as much as possible. In addition, it is thought that immunity is also reduced by leukopenia.

This time we experienced the evulsion of a deciduous tooth of an FA boy. Age was 7 years and the platelet count was 64,000/µL. Because the root of the tooth had been physiologically resorbed with the eruption of the subsequent permanent tooth, bleeding after evulsion was considered to be minimal. Bleeding was actually minimal, and hemostasis was achieved after 5 minutes of gauze compression. In addition, we were able to prevent infection by taking antibacterial drugs internally before and after the procedure under the instruction of the attending physician.

Verruciform xanthoma is a benign mucosal disease characterized by papillary proliferation of coated stratified squamous epithelium and aggregation of foam cells confined to the connective tissue papillae, and is considered a reactive change rather than a true tumor. It is generally found in the genital organs and skin, but it can also be found in the oral cavity. We report three cases of verruciform xanthoma, each with intraoral findings: a band of coarse surface whitish plaque on the lingual gingiva of the left mandibular premolar, a similarly round, surface granular yellowish-white papule on the lingual gingiva of the right mandibular premolar, and a granular surface pale yellow mass on the buccal gingiva of the left maxillary premolar. All three cases were resected and are doing well.