The primary goal of dental implant treatment is to restore the masticatory function of missing teeth. Therefore, a critical aspect is determining when and to what extent we can apply load to the implant throughout the treatment process. In order to clarify the effects of load on the osseointegrated implant, we focused on the bone quality around the implant. Fortunately, we encountered the concept of “bone preferential alignment” as an evaluation method for bone quality. Subsequently, we ultimately achieved the practical realization of a novel thread design for dental implants capable of influencing bone quality under various loads.

In this article, we provide an overview of the development research with regard to the newly launched implant design. We also explore the process of obtaining intellectual property rights associated with our research efforts and propose an ideal method for sharing these rights with society.

For patients who cannot take care of their own oral cavity, the idea of controlling biofilms by using the factors involved in biofilm formation has led to industry-academia collaboration. There are two major researches, the first is the use of L8020 lactic acid bacteria. The oral cavity contains a resident microflora called oral flora. Similar to the intestinal flora, oral flora contain lactic acid bacteria, so we have been conducting research on the application of probiotics to the oral cavity. In particular, we introduce seeds using Lactobacillus rhamnosus (L8020 lactic acid bacterium), which exhibits high antibacterial effects against mutans streptococci, periodontalburdens, and Candida species.

Second, in order to add antibacterial properties to the surface of teeth and implants, we developed Etak, which has both an antiseptic part used for disinfecting skins and/or mucosa, and a silane-based immobilization part. The Etak makes it possible to easily antibacterially process things that have not had antibacterial properties so far just by spraying or immersing them. This Etak also has an antiviral effect and is used for various purposes.

In this paper, we would like to introduce specific examples of industry-university collaborative research, such as patent acquisition and royalties from L8020 and Etak.

In evidence-based medicine since 1990’s, randomized controlled trials (RCTs) have been regarded as the most valuable clinical studies. However, treatment efficacy in RCTs is not always observed in clinical settings in the real world. Large-scale real-world data (RWD) is very useful to confirm clinical effectiveness of treatments in the real world, which RCTs have suggested. Observational studies using RWD are very susceptible to various biases. To control these biases, scientists should use appropriate methods, including propensity score method and instrumental variable method.

In recent years, “real-world data” collected from actual events, occurrences, or observations in the fields of healthcare and caregiving has been increasingly utilized in clinical research. This paper presents findings from a large cohort study on the association among partially edentulous arch, tooth loss, and all-cause mortality. This study is based on approximately 250,000 data points from dental checkups of older adults conducted in Osaka Prefecture from 2017 to 2021, as well as medical claim data from the Kokuho Database. The discussion focuses on the impact of partially edentulous arch on the subsequent loss of remaining teeth and systemic health from the viewpoint of Eichner’s, Cummer’s, and Miyaji’s classifications for missing dentition.

Generally, obesity and aging have been listed as causes of obstructive sleep apnea (OSA). Actually, the incidence of OSA increases with increasing levels of obesity and ageing. Additionally, gender differences in OSA incidence have been reported, with a higher incidence in males compared to females.

Therefore, from an epidemiological perspective, these three factors are considered to contribute to the cause of OSA. However, the detailed mechanism of OSA onset by these factors has not been revealed.

In this present report, the relationship between OSA onset and the aforementioned three factors was investigated through image-based observations, including the findings from previous imaging studies. Furthermore, compensatory response on awakening and other incidental findings related to OSA were investigated using cephalometric imaging and computed tomography.

Dentists fabricate oral appliances (OA) for patients with obstructive sleep apnea (OSA). OA therapy requires written correspondence, such as a letter of request for examination to a medical institution and a written prescription for an OA to dental technicians. A system of medical–dental collaboration centered on the patient is required to ensure smooth treatment and continuous follow-up. In this article, we introduce some key points that dentists should keep in mind when collaborating with medical institutions and dental laboratories for OA therapy for patients with OSA.

Purpose: This study examined the pathological classification of patients with occlusal discomfort syndrome (ODS) and the influencing factors involved in the pathological condition.

Objective: The subjects were 72 patients who complained of occlusal discomfort out of 272 patients who visited the specialized outpatient clinic at Kanagawa Dental University Hospital between January 17, 2012 and December 7, 2021.

Method: A medical interview was conducted based on the pre-examination chart, structured interview, the trigger for the onset of symptoms, and the results of examinations of occlusion and temporomandibular joints. Classification of ODS based on the pathological condition was performed, and modifiers were extracted from the obtained background of each patient, and the level of its strength was evaluated.

Results: The 72 subjects selected according to the ODS definition included 15 males (mean age 51.8±16.1) and 57 females (mean age 54.4±11.7).

The pathology could be classified into ODS due to occlusal disorder (ODS type I), ODS due to temporomandibular joint disorder (ODS type II), and ODS due to oral psychosomatic disorder (ODS type III). The frequency was 46% for ODS type I, 10% for type II, and 44% for type III. The influencing factors were classified into (1) psychosocial environmental factors, (2) patient-dentist relationship factors, (3) personality tendency factors, (4) psychological factors, (5) other factors, and (6) none, and their involvement levels were ODS I, II, and III. Significant differences in proportion of the factors were observed between the types.

Conclusion: The pathological classification of ODS was clarified, and the results suggested the importance of evaluating its influencing factors and their level.

Purpose: In this retrospective study, the longevity of full and facing cast crowns placed by six general practitioners and influencing factors were investigated.

Methods: All participants (20 years or older) had first visited respective dental clinics more than 10 years ago and had a history of full and/or facing cast crowns placed by the six dentists. To reduce selection bias, information about only the first full and/or facing cast crowns placed was obtained from the medical charts and recorded in the case report form. Survival time was defined as the period of time until the crown was retreated. If the crown was still surviving at the last examination, the case was treated as a censored case. Survival analysis was performed using the Kaplan–Meier method and log-rank test, and the Cox proportional hazards model.

Results: Information about the survival time of 824 cast crowns, 542 full cast crowns and 282 facing cast crowns was obtained from 682 participants. Ten-year survival rates for full cast crowns and facing cast crowns were 74.2% and 75.3%, and their median survival times were 20.8 years and 19.7 years, respectively. Main reasons for retreatment of the crowns were crown dislodgement, periapical periodontitis, root fracture and prosthetic requests. It was revealed that treatment history (initially placed or replaced) had the greatest influence on the longevity of the cast crowns (hazard ratio: 3.4), followed by the operator, the number of remaining teeth at the time of placement, and the retreatment risk at the time of placement.

Conclusion: The median survival time for all cast crowns was estimated at 20.7 years, but was found to be significantly shorter for replaced crowns at 14.6 years.

Patient: The patient was a 62-year-old woman with the chief complaint of tooth movement and pain during mastication due to severe marginal periodontitis. After tooth extraction, treatment dentures were used to examine the intermaxillary relationship, denture morphology and esthetics. A metal denture was fabricated as the final prosthesis.

Discussion: Four years have passed since wearing the dentures, and the patient reported that there was no pain wearing the dentures and that no dentures had broken. The patient’s satisfaction was high, suggesting that good results were obtained.

Conclusion: A lot of teeth were extracted for severe marginal periodontitis, followed by an examination of the intermaxillary relationship and esthetics using treatment dentures. It is thought that good results were obtained by reflecting this in the final prosthetic device.

Patient: A 63-year-old man presented with the chief complaint of difficulty in mastication due to the inappropriate mobility of a fixed partial denture attached to the left molar of the mandible. After extraction of the tooth with a poor prognosis that was causing the mobility of the fixed partial denture, implant treatment was performed on the mandibular left molar.

Discussion: Masticatory function was found to have improved after treatment of the tooth with a poor prognosis and placement of an implant-supported prostheses. The use of an intraoral scanner enabled the fabrication of a well-fitting prosthetic device, which was thought to have brought about a stable outcome.

Conclusion: In this case, fabrication of an implant-supported prosthesis using an intraoral scanner after placement of two implants resulted in the improvement of masticatory disorders, since it was possible to achieve high impression accuracy and simplification of the maxillomandibular registration.

Patient: A 62-year-old female visited our department complaining of pain in the upper left tooth. The upper left first premolar was extracted due to a root fracture. Implants were placed in the upper left posterior region, avoiding the first premolar site, because the root of the upper left canine was significantly distally inclined. Subsequently, an implant-supported hybrid composite resin-facing fixed partial denture with a mesial cantilever, made of a gold alloy, was installed.

Discussion: Since excessive occlusal forces and parafunction were suspected due to a history of root fracture, the occlusal surface of the final prosthesis was made of metal to prevent wear and chipping, which resulted in a stable long-term outcome.

Conclusion: The implant prosthesis for a patient with Kennedy class II partially edentulous resulted in good outcomes with high patient satisfaction by establishing occlusal support and selecting materials that can withstand occlusal force, along with concurrent training for oral function to help improve and maintain mastication.

Patient: The patient was a 59-year-old woman with the chief complaint of difficulty eating. Masticatory disorder due to defects in the left upper and right lower molars was diagnosed, and masticatory function was improved using fixed implant dentures. One of the causes of the defects was suspected to be the load on the molars during lateral mandibular movement, so a canine-guided occlusion was applied. After follow-up by provisional restoration, a definitive prosthesis reproducing the morphology was replaced.

Discussion: In this case, an implant denture was used at the site of the molar defect during lateral mandibular movement.

Conclusion: As a result of implant prosthetic treatment for masticatory disturbance caused by defects of the left upper molar and right lower molar, oral health-related quality of life (QOL) was improved.

Patient: A 59-year-old male was referred to us complaining of discomfort of a maxillary removable partial denture. He had a mild gag reflex and decreased interocclusal clearance and prosthetic space. After examining the gag reflex-inducing area, the vertical dimension was increased using a treatment denture and provisional restoration. The positions and types of major connectors that would not cause discomfort were verified using several types of record bases with occlusion rims. Desensitization therapy was used to reduce the gag reflex. Following all examinations, definitive prostheses, including a removable maxillary partial denture, were provided.

Discussion: The final prosthesis was fabricated after careful and sufficient examinations for discomfort, enabling a good long-term esthetic and functional prognosis.

Conclusion: A chief complaint of discomfort with a maxillary removable partial denture was appropriately addressed, and good long-term results and patient satisfaction were achieved with the definitive prosthesis.

Patient: An 80-year-old male with edentulous upper and lower jaws presented to our hospital with a chief complaint of dislodged and lifted dentures when opening the mouth even slightly and difficulty in mastication. He had infraocclusion and residual ridge resorption of the mandibular left side. In order to stabilize the denture, the denture base area was expanded and the treatment denture was placed at a height of 3 mm. The final denture was then placed with reference to the treatment denture.

Discussion: Oral health related QOL, masticatory performance and masticatory path pattern when using gummy jellies, and intraoral water content showed good values after use of the treatment denture and the new denture.

Conclusion: The application of new dentures to an edentulous patient with infraocclusion after applying the treatment denture resulted in improved oral QOL and masticatory performance, and showed good long-term results.

Patient: A 65-year-old man presented with the chief complaint of masticatory disorders. The patient exhibited loss of occlusal support in the posterior teeth, along with severe disruption of the occlusal plane. Additionally, there was attrition in the anterior teeth with a decrease in the occlusal vertical dimension and compromised esthetics. A comprehensive full-arch prosthetic treatment was undertaken with bite-raising.

Discussion: It is inferred that good results regarding masticatory function and esthetics were obtained by performing prosthetic treatment considering the prosthodontic reference plane and design of the prosthetic device using zirconia.

Conclusion: This case report describes the favorable clinical outcome in a patient with reduced occlusal vertical dimension secondary to the loss of posterior occlusal support. The problem was successfully mitigated through a comprehensive full-mouth rehabilitation regimen, strategically calibrated in order to establish an optimal prosthodontic reference plane and to restore the occlusal vertical dimension to its appropriate state.

Patient: A 65-year-old female patient presented at our clinic with a chief complaint of esthetic dissatisfaction caused by repeated direct restorative treatments on her maxillary anterior teeth. The patient was diagnosed with secondary caries and associated esthetic problems after multiple restorative treatments, and it was decided to place porcelain-veneered zirconia crowns on the six maxillary anterior teeth.

Discussion: The patient achieved a favorable long-term outcome due to the appropriate selection of material, prosthetic design, and adhesive bonding, with attention given to the occlusal relationship.

Conclusion: By utilizing porcelain-veneered zirconia crowns on the six maxillary anterior teeth, a sustained and esthetically pleasing improvement was attained, ensuring long-term stability.

Patient: A 79-year-old female presented with esthetic, pronunciation and masticatory problems due to defects in anterior teeth. Metal allergy was noted on examination, and allergy test was performed. A treatment denture was inserted to stabilize the occlusion and teeth to be extracted was examined. After the extraction, anterior prosthesis was fabricated, and the final denture for upper and lower jaws was fabricated again.

Discussion: Metal allergy testing and removal of prosthetics under a rubber dam to prevent moisture minimized intraoperative allergy symptoms and improved patient satisfaction.

Conclusion: After metal allergy testing, a full mouth rehabilitation was performed on a patient with metal allergy, and the esthetic appearance was restored, masticatory ability and pronunciation were improved, and the patient’s oral-related quality of life (QoL) was improved.

Patient: A 44-year-old female patient with a left cleft lip and palate complained of esthetic problems. The diagnosis was that there were caries on the abutment teeth of a maxillary bridge. Teeth diagnosed as difficult to preserve were extracted. Esthetics were improved by placing maxillary provisional dentures, and later, an electroformed telescopic crown-retained denture was inserted to address the issue.

Discussion: Due to the imbalance of the remaining teeth between the maxilla and mandible, concerns arose about overloading the maxillary teeth. Thus, an electroformed telescopic crown-retained denture was chosen to enhance support, esthetics, and functional load distribution. The sufficient support by the telescopic denture reduced the stress on the remaining teeth and distributed the functional load, leading to a good treatment outcome.

Conclusion: Prosthetic treatment with an electroformed crown-retained telescopic denture improved esthetics and oral health-related quality of life for a maxillary partially edentulous arch with cleft lip and palate.

Patient: A 45-year-old male patient came to our hospital with a chief complaint of difficulty in mastication due to his maxillary denture coming off. The position of artificial teeth and polishing of the maxillary complete denture were improper. After adjusting the border sealing of the old denture, a new denture was fabricated based on the adjusted old denture. The patient was highly satisfied with the new denture.

Discussion: After improving the border sealing by applying tissue conditioner on the old denture, the conditioner was also applied to the border and polished surface of the new denture. The patient was able to masticate without dislocation of the denture by increased retention.

Conclusion: Considering the neutral zone of the maxilla and confirming the denture space, the border sealing of a maxillary complete denture in a patient with cleft lip and palate history was improved.

Patient: The patient was a 70-year-old male complaining of recurrent fracture of a mandibular partial denture. It was suggested that the fracture was attributable not only to insufficient denture space narrowed by mandibular tori and tongue feeling, but also to excessive functional force due to bruxism and food preference. The patient did not consent to osteoplasty of mandibular tori. A metal framework was applied, but structural vulnerability remained. To reduce the adverse effects of excessive functional force, selection of occlusal scheme, acquisition of adequate support area and behavior therapy for bruxism and food preference were implemented.

Discussion: In this case, strengthening of the mechanical properties of the denture, reduction of functional force on the denture and dispersion of functional force were necessary to avoid denture fracture.

Conclusion: For this high-risk case of denture fracture, multiple approaches to control denture fracture contributed to achieving a successful outcome.

Patient: A 67-year-old woman complained of loss of retention of a maxillary denture and discomfort in the mandibular premolars on both sides, and suffered non-vertical stop occlusion and occlusal curvature. Therefore, interim dentures were fabricated to determine the occlusal plane, and then definitive overdentures were fabricated with stud attachments.

Discussion: The diagnosis of occlusal plane with the interim dentures and the definitive overdentures with the stud attachments corrected the occlusal curvature and increased the support and retention of the dentures.

Conclusion: The overdentures with stud attachments for the patient with non-vertical stop occlusion improved the stability of the dentures and provided functional recovery.

Patient: A 56-year-old woman presented with pain in the temporomandibular joint area and masticatory dysfunction caused by temporomandibular disorders. Since intraoral examinations revealed occlusal interference and infraocclusion, a stabilization splint was temporarily used to improve them. Occlusal reconstruction via provisional restoration was performed in the stabilized condylar position followed by fabrication of the definitive prosthesis.

Discussion: Fabrication of the provisional restoration in the stabilized condylar position may have enabled occlusal reconstruction in a physiological jaw position. Furthermore, using provisional restorations as a reference for the definitive prosthesis likely facilitated favorable treatment results.

Conclusion: A favorable treatment course was achieved by the definitive prosthesis after occlusal reconstruction with a stabilization splint and provisional restorations.

Patient: A 66-year-old male visited our hospital with the chief complaint of difficulty in mastication. A decrease of denture space due to missing bilateral mandibular molars that had been left untreated for a long time was observed. In addition, scissor bite and deep bite had developed due to the lack of occlusal support. Occlusal reconstruction by increasing the vertical dimension was performed by a splint-type treatment denture, and then the definitive prosthetic procedures were performed.

Discussion: A splint-type treatment denture was used for achieving adequate space for the prostheses. After it was confirmed that the patient had adapted to the new mandibular position, cap clasps were applied to maintain posterior occlusal support and deal with the high occlusal forces. Cap clasps have a high supporting function and resulted in a favorable outcome.

Conclusion: In a patient with scissor bite, a partial denture with cap clasps may be effective for reconstructing the occlusal plane and occlusal support without aggressive crown prostheses.

Patient: The patient was a 69-year-old male with the chief complaints of masticatory disturbance due to attrition and root fracture. After examination, masticatory disturbance due to attrition was diagnosed.

Discussion: The patient was suspected to have an irregular occlusal plane and a decreased occlusal height due to attrition.

Conclusion: The decrease in occlusal height of a patient with attrition was determined with dentures. Then, follow-up was performed using a provisional restoration. Masticatory function was improved by reflecting its position.

Patient: The patient was a 73-year-old woman who complained of difficulty in mastication due to the movement of her maxillary partial denture and tooth movement. After diagnosis, the occlusal plane and occlusal vertical dimension were corrected by using a provisional restoration and a treatment denture. A metal plate denture was selected due to its connecting rigidity because the case was at the level of bite collapse. As preprosthetic treatment, crowns were placed on the abutment teeth, following which the metal plate denture was inserted.

Discussion: In order to prevent the denture from rotating and sinking, a final prosthesis with a rigid connection was installed. As a result, proper support and bracing were obtained, occlusal forces could be distributed, and a good prognosis was achieved.

Conclusion: The masticatory ability of the patient, who was at the stage of bite collapse, was improved by wearing a definitive prosthesis with enhanced connector rigidity.

Patient: A 73-year-old woman complained of loose dentures and poor esthetics. The diagnosis determined that the occlusal height had decreased due to the misalignment. A metal base denture was designed considering the connecting rigidity between the abutment tooth and the denture, crown restoration was performed as a preprosthetic treatment, and the metal base denture was attached.

Discussion: Occlusal elevation improved the denture spaces, and a denture with improved esthetics could be fabricated. A good prognosis was obtained by a design that increased the strength of the connection between the abutment tooth and denture, dispersing the occlusal force and suppressing the movement of the denture.

Conclusion: In this case of non-vertical stop occlusion due to a decrease in occlusal height, it was possible to resolve the chief complaint by occlusal elevation and the attachment of a final prosthesis with increased connecting rigidity.

Patient: A 63-year-old female patient desired improvement of masticatory disturbance due to incompatibility of the maxillary complete denture and mandibular partial denture for missing 7+7 and 765|567 teeth, respectively; and improvement of taste disturbance due to palatal coverage of the denture. Functional restoration was achieved with a maxillary bone-anchored complete denture (immediate loading) for the 7+7 missing teeth (immediate restoration) and crown-type implant dentures for the 765|567 missing teeth.

Discussion: After functional restoration, the taste and masticatory disturbances did not reappear and there were no prosthetic complications such as detachment or breaking, with a good overall follow-up.

Conclusion: The maxillary immediate restorative implant-supported prosthetic treatment is considered to be one of the most effective treatment options for patients with the C2 defect pattern of Eichner’s classification having masticatory and taste disorders as their main complaints.

Patient: The patient was a 76-year-old male who complained of difficulty in mastication due to instability of a mandibular complete denture. The previous dentures showed significant occlusal wear of the artificial teeth in both the maxilla and mandible, and the dentures moved during occlusion due to the poor fit of the impression surface. New complete dentures were fabricated to improve the position of the artificial teeth and to improve the polished surface of the dentures.

Discussion: The appropriate vertical and horizontal positioning of the mandible, the position of the artificial teeth, the occlusal scheme, and the denture form were all important for the stability of the dentures and the improvement of masticatory ability.

Conclusion: The patient’s denture stability and masticatory function were improved by the appropriate mandibular position and denture form.

Patient: The patient was a 29-year-old woman who complained of poor esthetics and difficulty in mastication due to teeth loss and fractures owing to traffic accident trauma. Dental implant treatment and fixed prosthodontic treatment were performed. Although the alveolar ridge in the maxillary anterior region was marginally displaced to the palatal side due to trauma, the esthetics and masticatory function were improved by prosthodontic consideration of the superstructure.

Discussion: A favorable outcome and high patient satisfaction were achieved as a result of improvement in lip support by contour adjustments of the implant superstructure, use of gingival-colored porcelain, selection of suitable abutments, and ensuring appropriate occlusion.

Conclusion: Prosthodontic consideration of the dental implant superstructure is crucial when the implant placement position is not ideal due to alveolar ridge displacement.

Patient: A 63-year-old man complained of poor esthetic morphology and esthetics of his anterior teeth. Reduction of the occlusal vertical dimension caused by severe tooth attrition was found. After full-arch provisional restorations were fabricated, occlusal and morphological adjustments were performed for approximately one year. The final prostheses that accurately reproduced the morphology of the provisional restorations were fabricated using computer-aided design (CAD).

Discussion: Reproduction of the morphology of the provisional restorations, which was established through long-term adjustments, in the final prostheses using CAD achieved functional prosthodontic treatment with improved quality of life.

Conclusion: The occlusal reconstruction for the patient with reduction of the occlusal vertical dimension due to severe attrition led to good esthetics and predictability.

Patient: The occlusal plane and horizontal mandibular position are important in cases of multiple missing teeth with loss of occlusal support of the molars. This patient had edentulous maxilla and bilateral free-end missing in the mandible and was wearing a denture only for the maxilla. The patient had lost occlusal support a long time ago and so the jaw position was unstable and the occlusal plane was declined.

Discussion: The occlusal plane was corrected and molar occlusal support was established. The horizontal position of the jaw was evaluated using the gothic arch drawing method, and a prosthesis was fabricated at an appropriate mandibular position.

Conclusion: Provisional restorations and treatment dentures were placed first, and then evaluated using the gothic arch drawing method. As a result, the fabricated prosthetic appliance achieved good results.

Patient: A 54-year-old male patient complained of poor mastication caused by expansion of a defect of the molars and an ill-fitting maxillary denture. Occlusal support was present in only one area. Excessive occlusal force on the maxillary anterior prosthesis by mandibular anterior teeth was thought to be responsible for early detachment and damage to the abutment teeth, putting the patient at risk of developing a non-vertical stop occlusion. A bridge for the maxillary anterior teeth as primary splinting and partial dentures were provided, which restored esthetics and masticatory function.

Discussion: More than three years after the treatment, the bridge, partial dentures, and remaining teeth remain healthy as a result of starting treatment before the loss of occlusal support and maintaining frequent follow-up appointments.

Conclusion: Use of a maxillary anterior bridge as primary splinting and partial posterior dentures prevented progression to non-vertical stop occlusion.

Patient: A 36-year-old female visited our hospital complaining of poor esthetics and difficulty in chewing. The patient had dental phobia and had been treated with only first aid. She was diagnosed with poor esthetics and masticatory disorder due to caries and loss of occlusal support in the molars, therefore, it was decided to treat with a fixed bridge in the upper jaw and a removable partial denture in the lower jaw.

Discussion: Because orthodontic extrusion was performed on the canine teeth involved in the lateral guide, primary fixation was applied to distribute the force during the lateral guide. Face-bow transfer, gothic arch tracing method, lateral check bite-taking, and adjustment of the condylar path of the articulator were performed, resulting in good reproducibility of mandibular movement on the articulator.

Conclusion: Full-mouth prosthodontic treatment improved the patient’s quality of life and resulted in long-term success.

Patient: We present the case of a 79-year-old man who came to the clinic with a chief complaint of ill-fitting and painful dentures made by his family doctor. He had low clearance due to abrasion and repeated fractures of the retention appliance. A new maxillary denture with a metal base was fabricated, and replacement with metal teeth was performed to maintain the occlusal height.

Discussion: The patient was able to maintain a high value in the masticatory function test as a result of the new denture replacement with metal teeth before the occlusal height decreased.

Conclusion: In this case, metal teeth were used to restore the function of a partial denture in a patient with reduced occlusal height due to missing molars, high occlusal force, and significant abrasion, suggesting the usefulness of metal teeth for maintaining the occlusal height.

Patient: The patient was a 74-year-old female with the complaint of esthetic problems due to wear in the anterior teeth and chewing difficulties due to fracture in the molar region. Occlusal reconstruction to increase the occlusal vertical dimension using a composite resin in the anterior teeth and a removable partial denture was performed.

Discussion: The occlusal vertical dimension was increased to ensure clearance and provide an esthetic crown morphology. Occlusal reconstruction was able to control the occlusion. It is important to follow up and monitor changes in occlusal status.

Conclusion: Occlusal reconstruction by increasing the occlusal vertical dimension in a case of esthetic and chewing difficulties due to tooth wear resulted in better esthetics and function.

Patient: A 65-year-old male patient presented with chief complaints of difficulty with his removable partial denture and esthetic impairment in the anterior teeth. The patient desired restoration of masticatory function and esthetics with a fixed prosthesis. To resolve his chief complaint, a fixed dental bridge and a fixed implant-supported prosthesis were planned to restore function.

Discussion: Converting the removable partial denture into a fixed prosthesis supported by implants led to the patient’s satisfaction. During the recall period of 3 years after the final restoration, no inflammation of the implant body or fracture of the superstructure body have been found.

Conclusion: In this patient presenting with complaints of masticatory disturbance and esthetic impairment, the application of fixed prosthodontics produced excellent results.

Patient: A 47-year-old woman visited our hospital with the chief complaint of esthetic and masticatory dysfunction, and limitation of mouth opening. She was examined and diagnosed with infra-occlusion and functional reversed articulation. She underwent occlusal reconstruction, following fabrication of the final prosthesis.

Discussion: By using an occlusal stabilization appliance, proper vertical height of occlusion with which the patient felt comfortable was confirmed. In addition, proper anterior guidance and occlusion were checked by transferring the provisional restoration to the final occlusal relation.

Conclusion: In the present case, the jaw position was determined first, then the occlusion was reconstructed by using a stabilization appliance, and the final prosthesis was fabricated using a check bite. As a result, the esthetics and masticatory dysfunction were improved.

Patient: A 34-year-old female visited our clinic with the chief complaint of difficulty of mastication and esthetic disturbance. She had an underbite due to crowded maxillary dentition and multiple missing teeth in the posterior region. Prior to prosthetic treatment, hopeless teeth were extracted. Implant and orthodontic treatment were performed.

Discussion: It is considered that functional pressure was appropriately distributed by providing an appropriate anterior guidance, and mastication and esthetics remain good.

Conclusion: In the present case, the occlusion was restored by an implant prosthesis and orthodontic treatment for a patient with occlusal collapse, and good results were obtained.

Patient: The patient was a 69-year-old woman who experienced pain due to periodontitis and difficulty in mastication due to fracture and movement of an implant. Bilaterally missing molars caused a significant decrease in the occlusal supporting area. Prosthetic treatment with dental implants and a cantilever bridge resulted in a good prognosis.

Discussion: Although the patient did not undergo complete dental reconstruction, her masticatory function was recovered, and her oral health-related quality of life was improved. The treatment plan was challenging, aimed at avoiding the need for hard-to-adapt dentures and minimizing surgical invasiveness.

Conclusion: Satisfactory functional restoration was achieved by selectively using fixed prosthodontic treatment with the shortened dental arch concept.

Patient: A 68-year-old woman visited our clinic for mastication-related and esthetic issues. After extracting unsalvageable teeth, treatment prostheses were fabricated. After functional and morphological evaluation of the treatment prostheses, upper and lower telescopic dental prostheses were fabricated.

Discussion: Telescopic dental prostheses were used to provide secondary fixation to the remaining mandibular teeth, thereby improving the denture stability, mastication, and esthetics.

Conclusion: Upper and lower telescopic dental prostheses restored masticatory function and improved esthetics in a patient with multiple missing teeth, leading to high satisfaction.

Patient: The patient was a 74-year-old man with the complaint of pain in the mandibular basal seat mucosa. He was diagnosed with a masticatory disorder because of pain in the basal seat mucosa caused by severe alveolar ridge absorption and mandibular torus. New sets of complete dentures were made using a closed-mouth functional impression with duplicate dentures, and soft relining was performed on the mandibular denture.

Discussion: Using a duplicate denture enabled dentures to be made while preserving the form of the old denture. Applying soft relining to the mandibular denture prevented the accumulation of occlusal force on the mucosa in the mandibular ridges when using the bone ridges for denture retention. This improved the retention and support of dentures, occlusal force, and masticatory function.

Conclusion: For cases of severe alveolar ridge absorption and mandibular torus, applying soft relining and using an undercut of the mandibular torus are considered effective.

Patient: A 61-year-old woman presented with the chief complaint of mastication difficulty due to ill-fitting dentures. Full-mouth treatment was performed after implant installation.

Discussion: Five and a half years after the treatment, no significant change was observed in the occlusion. Long-term stability of the occlusion was achieved with the use of monolithic zirconia that restrains changes in occlusal form, supports oral implants for occlusion, and removes malocclusion in lateral excursions by improving the functional reverse articulation.

Conclusion: In this case, both the application of oral implant treatment and the improvement of functional reverse articulation led to the restoration of masticatory function.

Patient: The patient, a 37-year-old woman, presented with a chief complaint of pain and unusual feeling of the maxillary anterior teeth. The patient underwent extraction of 1|12 owing to root resorption, and first stage surgery 1| on |2 and was performed. Digital impressions of the morphology of the provisional restoration and gingival and mucosal morphology were taken using an intraoral scanner, and the obtained morphological data were used to fabricate a screw-retained 1|12 final superstructure using monolithic zirconia, which was placed in the patient.

Discussion: The method used in this case is more straightforward than the conventional method and reduces the time required for treatment and fabrication, as well as the materials used such as impression materials and plaster.

Conclusion: No clinical complications or fractures were reported after the implant superstructure fabricated using a fully digital workflow was delivered to the patient.

Patient: A 44-year-old man, who suffered from hemophilia A and had multiple hopeless teeth, visited our clinic to have dentures made. A full mouth provisional restoration and its modification after teeth extraction was used to first maintain the occlusal vertical dimension and then raise it. The finally obtained occlusion was transferred to the fixed and removable partial dentures, resulting in functional and esthetic recovery.

Discussion: The well-planned provisional restoration and timing of tooth extractions could prevent hemophilia A from causing systemic trouble. Although multiple tooth extractions reduced occlusal support, the provisional occlusal modification attained an optimal level of occlusal vertical dimension functionally and anterior tooth morphology esthetically.

Conclusion: Subjective satisfaction in terms of masticatory function and esthetics increased after treatment. Well-planned teeth extraction and careful adjustment of the provisional prostheses might have contributed to this outcome.

Patient: The patient was a 55-year-old male who came to the hospital complaining that his denture had fractured. After extracting the remaining teeth and fabricating complete dentures, an embolization part made with reference to the speech aid used was attached to improve the nasopharyngeal insufficiency.

Discussion: By sufficiently explaining the treatment, it was possible to continue the treatment for the patient with poor literacy of the oral cavity. Also, choosing complete dentures for the treatment led to a good prognosis.

Conclusion: Since the speech aid used maintained good nasopharyngeal closure, replicating the morphology and incorporating it into new dentures did not change the nasopharyngeal closure, leading to a good prognosis.

Patient: The patient was a 22-year-old female who visited our department with a chief complaint of esthetic dissatisfaction due to intermediary defect of a maxillary anterior tooth. The examination revealed insufficient bone on the labial side, so implant placement with osteogenesis was performed. The final prosthesis with a zirconia-based all-ceramic restoration was fabricated for esthetic improvement.

Discussion: By using an angled screw channel as an implant superstructure and reflecting the shape of the provisional restoration in the final superstructure, a crown prosthetic device with excellent functionality, esthetics, and cleanability could be fabricated.

Conclusion: It is considered that bone augmentation and implant treatment are effective in restoring esthetics and good oral function in cases with intermediary defects of maxillary anterior teeth.

Patient: A 66-year-old woman was suffering from poor esthetics of the anterior teeth and difficulty chewing due to extensive tooth attrition. Severe tooth attrition, a decrease in the occlusal vertical dimension, and poor denture fit were observed. Full-mouth rehabilitation, including an increase in the occlusal vertical dimension, was performed to improve the patient’s esthetic and masticatory function.

Discussion: After carefully increasing the vertical dimension of occlusion using an occlusal appliance and provisional restorations, definitive restorations and dentures were provided to the patient. These treatment interventions may have contributed to high patient satisfaction in terms of esthetics and function and improved oral health-related quality of life.

Conclusion: Full-mouth rehabilitation, including an increase in the occlusal vertical dimension, enables patients with severe attrition to achieve improved esthetics and function.