The concept of the biomimetic approach to restorative dentistry is currently widespread, and adhesive restorationsthat preserve enamel and tooth structure as much as possible are becoming a mainstream approach worldwide.Thanks to the advance of adhesive technology and the advent and evolution of dental implants, an aggressive toothpreparation for crown and bridge restorations to provide conventional retention and resistance forms should nowonly be used in the case of retreatment, for both anterior and posterior teeth. Since it is difficult to regenerate thehard tissues of teeth at this stage, the objective of restorative treatment is to minimize treatment invasion, preservethe remaining tooth structure and tissues, and maximize the advantages inherent in natural teeth, approximatingand reproducing the biological, structural mechanical, functional, and esthetic properties of the natural teeth. Thetooth preparation design of posterior veneer restorations should be derived on an individual case basis from the followingaspects: 1) remaining tooth structure and surface coverage, 2) bond quality, 3) biomechanics, 4) tooth flexureeffects, 5) maintenance of the bonding interface, 6) material selection, 7) material thickness, and so on. In this review,we discussed the recommended basic preparation designs for anterior veneer restoration from both evidence-basedand experience-based perspectives, with reference to the literature. Therefore, we propose a systematic classificationof occlusal veneers based on the preservation of enamel.

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It has been seven years since developmental insufficiency of oral function (DIOF) was firstlisted under Japanese universal health care coverage. Although we dental healthcare professionalshave started to tackle this issue and support in clinical settings is gradually becoming morecommon, we do not feel that the oral functions of children have improved. As we do not yet havea clear way of measuring and evaluating oral functions, it is difficult to tell whether they are improvingor deteriorating, but this is precisely why it is essential to take a scientific approach inthis field in the future. To this end, this paper first lays out the current evidence on breastfeedingsupport and weaning support which are related to the development of oral function and eatingbehavior in pursuit of better childcare support.

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A removable partial denture (RPD) with a proper design and fabrication can be expected to maintainthe occlusal relationship for a long time without adversely affecting the remaining tissues, even whensubjected to repeated loads of severe occlusal forces over many years, and to extend the period of dentureuse. Conversely, an improperly designed denture can cause the mobility or loss of the remaining teeth, aswell as alveolar ridge resorption, which can lead to denture malfunctions and fractures, which can causerepeated instability of the occlusion and the need for dentures to be remade, ultimately ending in occlusalcollapse. The process of losing the remaining teeth due to improper prosthetic treatment and occlusal collapseis a negative spiral caused by a chain reaction that ends in an Eichner classification C1 or edentulousjaw. To prevent such situations, we should aim to manufacture dentures that can be used for a long timethat protect from further tooth loss. RPD designs must satisfy functional, physiological, and aesthetic conditions.They must be strong, durable, and adapt easily to changes. This article considers the essences ofRPD that have been used for more than 50 years. The principles of denture design with the goal of preservingthe remaining tissue, structural design to prevent denture fractures, and what dentures should be liketo adapt to a super-aging society are also reviewed.

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In recent years, the relationship between occlusion and systemic diseases has been attracting attention, and ithas been suggested that occlusion in particular is deeply related to systemic diseases such as temporomandibularjoint disorders and headaches. In Japan, taking the worldwide lead, treatment with occlusal appliances (biteraisingplates, mouthpieces, splints) was taken up at the Central Social Health and Medical Council in the 1990sas a treatment measure for temporomandibular joint disorders and as a preventive measure for bruxism, andwas in effect included in the medical fee schedule for public health insurance. As a result, in 2018, approximately750,000 appliances were prescribed annually. No appliance design, however, has gained a global consensus. Atour clinic, over 38 years of clinical practice, we have treated 17,000 registered patients, of whom more than 2,000were treated with occlusal appliances, incessantly tuning them up. The basic concept of our appliance, whichtook the current design in 2017, is an “appliance in harmony with the biological functions of each individual”,comparable to the “Ideal Occlusion” namely, the goal of full mouth reconstruction treatment. This is a design thatallows dynamic physiological swallowing functions to be performed unconsciously. In this report, we reviewed thedefinitions of terminology related to unclear definitions of the term “occlusion” cited in Glossary of ProsthodonticTeams (2023) and the 6th edition of Japanese Prosthodontics Glossary, based on clinical data from many full-mouthreconstructive treatments. We also verified the differences between Japan and the United States. We in turn proposea New Occlusal Concept, “Functional Balanced Occlusion within Centric Space,” by clarifying the positionsof the centric relation, centric occlusion, and centric relation occlusion, which are the basics of occlusal theory,using conceptual values based on an analysis of occlusion function. We named a device incorporating this occlusalconcept “CSO Appliance” and introduced it into clinical practice. We also recorded and analyzed changes inpatients' conditions before and after wearing the Appliance. Notable results include a reduction in symptoms in 127of 181 cases (69%) complained of headaches, and a reduction in symptoms in 119 of 206 cases (58%) complained ofdiscomfort in the temporomandibular joint, suggesting the positive effects of the “CSO Appliance”.

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We report on a case in which good treatment results were obtained using vital pulp therapy(VPT) for a deep carious lesion. A 28-year-old female first presented with a chief complaint ofcold pain. A deep carious lesion was found in #45, and since pulp expousure was anticipated, VPTusing MTA cement was planned. As accidental exposure of the pulp occurred during the removalof the infected tooth structure, a pulp diagnosis was performed under a strong magnifying fieldusing a microscope, and after pulp amputation at the cervical level, the pulp was capped withMTA cement. As the patient showed no signs of pulp symptoms such as spontaneous pain duringthe follow-up, the final prosthetic restoration was performed using a lithium disilicate glassceramicinlay. The main complaint of cold pain was improved, and good results were obtainedregarding esthetics and function.

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A 75-year-old female patient, who had developed Addison's disease in her 40s, presented witha chief complaint of being unable to eat properly since her 60s when she started wearing completedentures. Although loss of appetite due to Addison's disease was a concern, many of the issues withher occlusion and eating function were attributed to complete dentures. Therefore, the treatmentplan focused on first remounting and adjusting her current dentures to restore functionalitywhile concurrently fabricating new dentures. This approach allowed for relatively easy functionalrecovery. Twelve years have passed since the new dentures were made, and the patient has notreported any issue with the dentures.

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A male patient in his 50s with a chief complaint of esthetic disturbance underwent a full-maxillaryrestorative procedure using MI restoration and digital dentistry. This report aims to digest andshare treatment procedures and methods. The patient was treated with a complete jaw examinationto achieve an esthetic goal while preserving as much of the existing enamel and tooth structure aspossible. In the basic treatment, all enamel was preserved and re-evaluated, and the patient wastreated with an aligner orthodontic treatment as a pre-prosthetic treatment to improve the dentalaxis and minimize teeth cutting. After the end of the retention period, the patient was reevaluated. Aprinter model was extracted from the superposition of STL data from the intraoral scanner, DICOMdata from the CT, and facial photograph data. A mock-up was made for the patient and used forconsultation. A simulation of tooth cutting was performed on the mock-up, and after the provisionalrestoration was placed, restorative treatment was performed using an adhesive technique. While theformation of a conventional full crown results in a significant loss of tooth strength, an approach suchas this that preserves enamel may be effective for the long-term preservation and stability of teeth.In addition, the use of digital equipment for examination and diagnosis was helpful in referring toanatomical criteria and highly effective in providing consultation to the patient.

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