In clinical dentistry, it is necessary to treat the stomatognathic system as a functional unit rather than treating one tooth as a unit, and to perform examinations, diagnoses, and formulate treatment plans. A trend toward comprehensive treatment that began in the early 1900s has been established, and many long-term prognostic outcomes have been observed clinically. However, the quality of the treatment results also depends on the operator’s experience. Therefore, we thought to use digital equipment to incorporate patient-specific objective criteria into comprehensive treatment. Purpose: We aimed to treat a 38-year-old woman who came to our hospital with a chief complaint of mastication disorder due to detachment of the lower left bridge using digital equipment based on objective criteria. Conclusions: It was suggested that the use of digital equipment could lead to more accurate and comprehensive treatment.

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As we move towards a super-aging society, there is no doubt that the keywords for healthy longevity are improving immunity and basal metabolism, and dental treatment must help patients maintain their mental and physical health．However, 85.6% of people using dentures find it inconvenient when it comes to missing prostheses, and there are no shortage of medical com- plaints．Looking at the reality of these dentures, regardless of insurance or self-funding, they do not provide high performance, comfort, and longevity．By acquiring the skills to provide dentures, we can create healthy and healthy elderly people, reduce wasteful medical costs, and gain social support from the public．

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Purpose: To determine the change in coloration over time when oral moisturizing gel and distilled water are applied to the tooth surfaces. Methods: Twenty patients with healthy bilateral maxillary central incisors were recruited for the study. Using a spectrometer, color tones were measured at baseline, 5 minutes, and 10 minutes after application of oral moisturizing gel, and after covering with gauze impregnated with distilled water, respectively, and the color difference ΔE00 was calculated using CIE L*a*b*. Results: Significant differences were observed in all parameters of L*a*b* when using the moisturizing gel (p<0.05). In distilled water, significant differences were observed in all parameters except a* between baseline and 10 min post-baseline (p<0.05). No significant differences were found in both ΔL* and Δa* between 5 and 10 minutes after application with either the moisturizing gel or distilled water, but a significant difference was observed between the moisturizing gel group and the distilled water group (p < 0.05). The moisturizing gel showed a trend of increasing ΔL*, while distilled water showed a decreasing trend. No significant differences were observed in Δb* values between the groups (p ≥ 0.05). Similarly, no significant differences were observed in ΔE00 values between the groups (p ≥ 0.05). Conclusion: The color change was observed after 5 and 10 minutes when gel and distilled water were used on the tooth surfaces, but there was no significant difference between the two conditions.

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Objective: The purpose of this survey is to examine the quality of treatment in one aspect by surveying the status of rubber dam use among the members of the Society of Japan Clinical Dentistry (SJCD), and to consider measures to increase the rate of RDs use. Materials and Methods: A questionnaire-based survey was conducted among 1,338 members of SJCD dentists. A total of 19 questions were asked, including the use of RDs, past educational environment, and working conditions. The survey period was from September 22, 2022 to October 20, 2022. The collection and tabulation were outsourced to Cross Marketing Inc. to ensure anonymity. Results: The number of respondents was 449, and the response rate was 33.6%. 72.8% of the respondents at SJCD used RDs, and those who used RDs were aware of the need for them (80.7%). A χ² test was conducted between past and current use of RDs at their office, and significant differences were found in both use and non-use of RDs. Conclusion: The use of RDs by dentists at their past employers had a significant impact on their motivation to use RDs. Therefore, in order to improve the use of RDs, it is important to educate them about the need for RDs, but it is also highly necessary to make them aware that their actions are likely to have a significant impact on dental care in Japan.

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Objective: To evaluate the effectiveness of fluoride iontophoresis in treating dentin hypersensitivity and its toxicity to human periodontal ligament fibroblasts (HPdLF). Methods: The fluoride ion uptake in dentin slices was measured at different application times. Furthermore, HPdLF were cultured on dentin slices treated with fluoride ion to assess cytotoxicity. Additionally, a prospective interventional study evaluated pain reduction in patients. Results: A 10-minute fluoride iontophoresis significantly increased uptake compared to shorter application times and did not show toxicity to HPdLF survival rates. The 10-minute fluoride iontophoresis significantly reduced pain and was more effective than the conventional 3-minute treatment, suggesting its usefulness as a preoperative treatment for dentin hypersensitivity before root coverage procedures.

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Purpose: A cross-sectional observational study was conducted to determine the relationship between the amount of gingival recession and the amount of maxillary anterior crowding in patients aged 40 years or older who had started orthodontic treatment. Methods: Maxillary anterior crowding volume, gingival thickness, bleeding on probing (BOP), pocket depth (PD), and clinical attachment loss (CAL) were measured in 97 patients aged 40 years or older who had started orthodontic treatment. Results: The mean ± standard deviation of gingival recession was 2.06 ± 2.34 mm (median 1 mm, interquartile range 1.625 mm) in the group with maxillary anterior crowding volume of 5 mm or more, and 1.18 ± 1.38 mm (median 1 mm, interquartile range 1 mm) in the group with anterior crowding volume of less than 5 mm, showing no significant difference. The rank correlation coefficient between the amount of gingival recession in the same region and the amount of crowding in the maxillary anterior teeth was 0.269, showing a slight correlation. Conclusions: It was suggested that maxillary anterior crowding may have a lower risk of gingival recession than mandibular anterior crowding.

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In recent years, the maxillary tuberosity has attracted attention as a donor site for autologous bone grafts and as a potential site for orthodontic implant anchors. To utilize the maxillary tuberosity for bone grafting or for the safe placement of orthodontic anchors, detailed knowledge of its hard tissue morphology is essential. Although it has been reported that the morphology of the maxillary tuberosity varies among races, no detailed anatomical studies have been conducted in the Japanese population. The purpose of this study was to clarify the hard tissue morphology of the maxillary tuberosity using cone beam computed tomography (CBCT) data previously acquired for clinical purposes at general dental clinics. CBCT scans of male and female patients aged 20 years or older, obtained at a single institution between July 22, 2019, and July 2, 2023, were used as study materials. A total of 80 maxillary tuberosities were analyzed (41 in males and 39 in females), with a mean age of 43.2 ± 13.9 years. The bone width of the maxillary tuberosities was significantly greater in males than in females. The cortical bone thickness was significantly greater on the palatal side within the same patient and cross-sectional plane. A slight correlation was observed between age and the vertical bone height of the maxillary tuberosity in some measured cross-sections. These findings suggest that the anatomical hard tissue morphology of the maxillary tuberosity varies by gender and age, which should be considered when planning bone grafts or orthodontic anchor placement involving this region.

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Purpose: By visualizing and verifying the relationship between jaw movement and occlusal surface contact using a jaw movement measuring device (JMAnalyser), this study examined the clinical utility of the device. Materials and Methods: For patients with occlusal collapse, jaw movement was measured using a jaw movement measuring device. STL data obtained from an intraoral scanner was imported, and functional jaw movements were visualized using images. Discussion: With the development of digital equipment, it has become possible to capture detailed mandibular movements. By analyzing the data, it is possible to visualize jaw movement from the time of provisional restoration to the final prosthesis and one year post-treatment, thereby observing differences before and after surgery. This suggests a new application of digital solutions linked to diagnosis in daily clinical practice; however, issues such as the establishment of diagnostic criteria remain. Conclusion: By using a jaw movement measuring device to visualize the relationship between jaw movement and occlusal contact, we were able to compare the avoidance of dynamic occlusal interference and the stability of the static intercuspal position. However, regarding force control, which is essential for long-term tooth preservation, verification through long-term clinical occlusion practice fully confirmed the continued usefulness of analog dentistry. Digital dentistry is expected to further advance in this field in the future.

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Patients: We report two cases in which treatment plans were designed based on Turner’s classification, aiming to restore function in patients whose oral cavities had collapsed due to acid erosion. Discussion: In treating patients with occlusal collapse caused by erosion, it is essential to assess the presence of mandibular position discrepancy (between centric relation and maximum intercuspation), compensatory tooth extrusion depending on the rate of tooth wear progression, and reduction in occlusal vertical dimension. Successful outcomes require a thorough understanding of each patient’s individual condition. It is also necessary to select appropriate restorative options—such as crowns, occlusal veneers, and laminate veneers—tailored to the patient’s needs, in order to achieve optimal occlusion (anterior guidance, vertical stop) and stabilize the periodontal tissues. Conclusions: By understanding the lifestyle and preferences of each patient, referring to Turner’s Tooth Wear classification, and providing treatment with consideration for MI (minimally invasive) principles, we can offer long-term care that matches the progression of each case of dental erosion. This approach contributes to improved oral function and aesthetics.

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Teeth position is very important in prosthetic treatment, and if good anterior guidance cannot be obtained, orthodontic treat-ment is necessary. However, if there is a problem with the occlusion due to skeletal problems, surgical correction is required. Here, we report a case of skeletal mandibular prognathism in which prosthetic treatment was performed in cooperation with a surgeon and an orthodontist.

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Case Summary: Vertical changes or rotation of the occlusal plane are considered occlusal cants and may originate from either skeletal or dental factors. Such cants are also associated with facial asymmetry. It has been reported that the tilt of the maxillary occlusal plane correlates with lateral mandibular deviation, often deviating upward toward the side of mandibular displacement, which significantly impacts clinical function and esthetics. In this report, we describe a case involving a dental occlusal cant, multiple missing teeth, and unrestorable teeth. The patient was treated with orthodontic therapy and implant placement, along with a change in jaw position, resulting in favorable clinical outcomes. Discussion: The position of the maxillary central incisors was established as the esthetic reference point. Based on this, an appropriate horizontal jaw position and occlusal height were determined to assess the tooth position abnormality and develop a treatment plan. Tooth movement was performed with reduced mechanical pressure to improve esthetics and restore functional occlusion. Conclusion: When performing esthetic dental treatment, it is essential to diagnose not only intraoral conditions but also facial features. By integrating functional and esthetic diagnostics, a more stable and predictable long-term outcome can be achieved.

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Patients: She was 43 years old at the time of her first visit. She requested to replace metal teeth with ceramics. Her facial appear-ance showed lip incompetence, intraoral examination revealed an open bite between canine teeth, mild crowding, numerous prosthetic devices on the molars and unstable intercuspal position. Based on the cephalometric findings, a mild skeletal Class II open bite due to retroversion of the mandible was diagnosed. After adjusting the occlusion to the position where the canine teeth occlude, orthodontic treatment of the mandibular anterior teeth and restorative treatment such as non-prep veneers on the maxillary lateral incisors were performed. Four years later, the composite resin on the canine incisor had been lost and was replaced with veneer tips. Four years later, the occlusion is stable. Discussion: Slight counterclockwise rotation of the mandible was observed and lip closure was achieved. Conclusion: Traces of abrasion were indicative of the height of the occlusion. Non-prep veneers may be effective in improving the esthetics and anterior coupling in the case of mild open bite and plexus.

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Summary of the Case: Crowding of the anterior mandibular teeth often leads to a poor prognosis for root canal treatment and restoration of the anterior maxillary teeth. The patient was a 38-year-old female who presented with discomfort at the root of the upper anterior teeth and occasional pain in the right temporomandibular joint during mouth opening. Additionally, a silver crown on the lower left second molar (#37) had been removed. In this case, orthodontic treatment was performed to improve the mandibular position, the occlusal relationship between the upper and lower jaws, and the alignment of the teeth. The mandibular position was verified using axiographic analysis, and a final prosthesis was subsequently installed.

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