Healing of peri-implant diseases is still difficult, and there is no consensus on the best approach. In recent years, dental laser irradiation has attracted attention as an effective method for eliminating implant surface contaminants brought by peri-implant diseases. In this article, the effect of dental laser irradiation on the treatment of peri-implant diseases is revisited by reviewing literature on the effect of laser use.

In the super-aged society, dentistry needs to progress in proportion to population pyramid of the time. For that, the prime problem will be "reinforcement and enhancement of the medical/dental cooperation". With the rapid increase of the elderly people, systemic problems of the patients becomes big risk for future dentistry. By the way, less knowledge of dentists about "the concept of the systemic disease" and "the relations of oral and body" would be one problem here. Getting over this, medical/dental cooperation will be established and convinced definitely. And the medical side will understand that oral health influences whole body, that produces the importance of oral frailty surely. The presence of the implant treatment improves surely the prevention of oral frailty by implant treatment is possible.

We report a case in which a chipped carbide bar strayed into the maxillary sinus during a maxillary wisdom tooth extraction procedure. A 23-year-old female patient initially visited a local dentist for left maxillary wisdom tooth extraction. While performing a root split, the carbide bar disappeared and a panoramic X-ray image showed a single opaque substance in the maxillary sinus, which was thought to be the missing carbide bar. Since removal was difficult at the local clinic, the patient was referred to our department on the same day for consultation and treatment. At that first visit, bleeding from the tooth extraction socket was observed, thus hemostasis was performed, and an antibacterial drug prescribed to reduce inflammation. Fourteen days after entry of the foreign body, the carbide bar was removed from the left maxillary sinus under local anesthesia.

Biomechanical and prosthetic factors affecting the peri-implant bone change following the superstructure placement have been still unclear. This clinical pilot study aimed to evaluate the factors affecting the three-dimensional (3D) volumetric changes of peri-implant buccal bone using cone beam computed tomography (CBCT) data following the superstructure placement. Fifteen implants placed in a single mandibular molar or premolar area of 13 patients were enrolled in this study. A screw retained superstructure made of monolithic zirconia was placed at an average of 4.6 ± 1 months following implant placement. CBCT examinations were performed twice: at the superstructure placement and approximately 1-year (12.5 ± 0.9 months) following placement. 3D superimposition of the two sets of CBCT images was performed, and the peri-implant buccal bone volumetric change was calculated. Multiple regression analysis was conducted to evaluate the association between peri-implant buccal bone volumetric change and the biomechanical and prosthetic factors. Although both bone increase and decrease cases were observed, remarkable 3D buccal bone volumetric changes were not observed in most cases. Bone changes were significant surrounding the implant platform area compared to the implant apex area. Multiple regression analysis revealed that a large crown-to-implant ratio significantly influenced the 3D bone volumetric change (p < 0.05).

The objective of this study was to examine the characteristics of four commercially available resin composite blocks for CAD/CAM crowns of anterior teeth [Cerasmart Layer (CL),Katana Avencia N(AN),KZR-CAD HR4 E-VA (KE) and Shofu Block HC Hard AN (HA)]. The mechanical properties [Vickers hardness, flexural strength, and flexural modulus (storage in air at 23 ± 2℃ for 1 day, immersion in deionized water at 37 ± 2 ℃ for 7 days, or thermal cycling for 10,000 cycles)], inorganic filler content, surface roughness after toothbrush abrasion test (up to 12,000 strokes), water sorption (up to 28 days) and color difference (distilled water, coffee liquid, or curry liquid) were investigated for each resin composite block. The Vickers hardness of the blocks was in the order of AN<CL<KE<HA, which showed a trend same as that of the inorganic filler content. The flexural strength and flexural modulus after immersion in deionized water for 7 days or thermal cycling test for all blocks significantly decreased as compared with those in air. The toothbrush abrasion test showed that the surface roughness of each resin block increased as the number of abrasions increased. After 6-hour immersion, HA significantly increased the water sorption value as compared to the other blocks. The color difference after immersion in curry liquid for all blocks exceeded the value of 2.0 which is believed to distinguish the color difference by naked eyes. Under the present experimental conditions, mechanical properties, water sorption, abrasion by toothbrushing, color change behavior by food and beverage and inorganic filler contents of the resin blocks were varied among the resin composite blocks for CAD/CAM crowns of anterior teeth.

Tooth extraction prior to implant treatment often causes gingival recession and alveolar bone loss, resulting in esthetic problems at the time of prosthesis placement. Various soft and hard tissue augmentation techniques have been used to solve this problem, and it is a well-known fact that these techniques have often produced desirable outcomes. However, soft and hard tissue augmentation often involves significant surgical invasion, prolonged treatment time, and increased number of surgeries, all of which are undesirable process for the patient. In this study, we report on the use of the socket shield technique for immediate loading of implants, which is minimally invasive, shortens the treatment time, requires fewer surgeries, prevents postoperative gingival recession and alveolar bone loss, and achieves esthetic results.

In daily clinical practice, we are often faced with cases where pulp is guttationed when softened dentin is thoroughly removed, but we wish to preserve the pulp as much as possible. By removing the caries while remineralizing and rehardening the dentin with stepwise excision, the pulp can be preserved without guttation. In this report, we describe a case of pulp preservation using the Er:YAG laser to improve the accuracy of stepwise excision. Stepwise excision was performed according to the guidelines of the Japanese Society of Conservative Dentistry, and the pulp side was irradiated with Er:YAG laser (Erwin Adverl EVO: Morita; C400F 20pps, 30-40mj) before the pulp is covered with tannin and fluoride cement (The caries was gradually removed while remineralizing the teeth using a carboxylate cement (Hybond Temporary Cement Soft: shofu) containing tannin and a fluoride compound. As a result, a sufficiently hard remineralized image was observed after removal of the caries. This technique can be expected to activate the pulp and sterilize the fossa, and better remineralization can be expected.

In order to remove inflammatory substances in the root canal, it is necessary to perform adequate root canal irrigation in addition to proper root canal preparation. Conventional syringe irrigation and ultrasonic irrigation do not sufficiently clean the root canal while preventing irrigation solution leaking into the apical periodontium and any ensuing damage in the periodontia. Intracanal aspiration technique is a method that can clean the root apex with minimal leakage of irrigation solution out into the root apex. In the patient presented here, #47 was diagnosed with pulp necrosis in the root canal and symptomatic apical periodontitis. #37, the previously treated tooth, was diagnosed with symptomatic apical periodontitis, and root canal treatment was performed. #37 had deep periodontal pockets and an endo-perio lesion. Both teeth had a high probability of having inflammatory material extending to the root apex, but good results were obtained by root canal treatment using intracanal aspiration technique.

The expansion of the median palatine suture is often performed in pediatric orthodontic treatment guiding occlusal development. However, inadequate preoperative examination of the jaw position and symmetry may lead to misalignment of the dental arch and the median palatine suture, which may cause significant facial asymmetry in the future. Therefore, preoperative examination of the jaw position is important. Although a jaw movement measuring device can be used to examine the jaw position, due to the mismatch between the size of the ear rods and the child's ears and lack of understanding on the patientʼs part, the reliability of the results may be questionable. As such, there is a need for a more convenient method to examine the jaw position during lateral expansion and periodic follow-up after surgery. In this report discussed are cases of a 7-year and 4-month-old girl and a 7-year and 6-month-old girl, who came to the clinic for non-extraction treatment and were subsequently treated with stabilization splinting, which is Koide's technique, because of suspected misalignment of the jaw position at pre-expansion. And as a more simple and more reliable examination method, moire topography (KDD KD-Z for whole body) was employed. Further, the periodic evaluation using moire topography over the period of growth observation follow-up was performed to promote dentition and jawbone growth as symmetrical as possible, which altogether lead to good results and patient satisfaction.

This report is to present a case of occlusal reconstruction for a patient with occlusal collapse and a significant discordance in the skeletal relationship between the maxilla and mandible. A 53 years-old woman presented with the pain in the upper anterior teeth. The examination revealed that her maxillary anterior teeth were fractured due to the protrusion of the mandibular anterior teeth, caused by loss of molar occlusal support. Further, the periodontal tissues were swollen, and she was on the verge of losing occlusal support altogether. After treatment planning, a full mouth reconstruction was started, first with correction of occlusal plane using provisional restorations. Then, implant treatment with guide bone regeneration was performed. The maxillary molars were restored after crown lengthening and partial orthodontic treatment to improve the tooth axis. For functional recovery, the laterally deviated mandible with asymmetric ramus was restored with supported removable denture. For the anterior multiple-tooth defects in the maxilla, mechanical problems often caused by long-span bridges and esthetic problems often brought by clasps were avoided by application of implants. The results suggested that the use of implants and removable dentures for occlusal reconstruction of multiple missing teeth with jaw deformity is effective.

Due to root fracture or bridge fracture, teeth may not be preserved. It is a serious situation at any age, but deterioration of masticatory function can lead to deterioration of general health, especially in the elderly. In this case, root fracture and bridge fracture occurred in succession, and the cause of eating disorder due to mandibular molar defect was analyzed by occlusal examination and diagnosed in accordance with mouth-as-a-unit approach. Furthermore, in consideration of occlusal rehabilitation, ease of maintenance, and long-term stability, a treatment plan was formulated to recover the occlusion with a removable partial floor denture using the Konus-crown telescope technique for the abutment. As a result, an appropriate occlusal relationship was obtained and the masticatory ability was improved, and good results and patient satisfaction were obtained.