The post-and-core is a widely accepted method to restore endodontically treated teeth with compromised tooth structure. Currently, cast metal post-and-core systems and prefabricated fiber posts combined with composite resin cores are the most frequently options in dental clinical practice, but both also come with advantages and limitations. The development of computer-aided design/computer-aided manufacturing (CAD/CAM) custom fiber post-and-core represents one of the significant trends in the advancement of dentistry. Society of Digital Dental Industry, National Association of Health Industry and Enterprise Management organized experts to formulate Guidelines for CAD/CAM custom fiber post-and-core, standardizing the clinical operation procedures of this technology, enhancing the success rate of CAD/CAM custom fiber post-and-core, and promoting its application and development.
Computer-Aided Design ; Humans ; Post and Core Technique ; Composite Resins ; Dental Prosthesis Design

Digital technologies have become an integral part of complete denture restoration. With advancement in computer-aided design and computer-aided manufacturing (CAD/CAM), tools such as intraoral scanning, facial scanning, 3D printing, and numerical control machining are reshaping the workflow of complete denture restoration. Unlike conventional methods that rely heavily on clinical experience and manual techniques, digital technologies offer greater precision, predictability, and efficacy. They also streamline the process by reducing the number of patient visits and improving overall comfort. Despite these improvements, the clinical application of digital complete denture restoration still faces challenges that require further standardization. The major issues include appropriate case selection, establishing consistent digital workflows, and evaluating long-term outcomes. To address these challenges and provide clinical guidance for practitioners, this expert consensus outlines the principles, advantages, and limitations of digital complete denture technology. The aim of this review was to offer practical recommendations on indications, clinical procedures and precautions, evaluation metrics, and outcome assessment to support digital restoration of complete denture in clinical practice.
Humans ; Denture, Complete ; Computer-Aided Design ; Denture Design/methods* ; Consensus ; Printing, Three-Dimensional

OBJECTIVES: This study aims to explore the effect of improving clinical efficiency by replacing traditional impression workflow with centralized digital impression workflow. METHODS: The department of prosthodontics in Center of Stomatology, Peking University Shenzhen Hospital has improved the clinical workflow by replacing the traditional impression made by doctors using impression materials for each patient with a centralized digital impression made by one technician for all patients in the department. This cross-sectional study recorded the chairside time required for impression taking in patients undergoing single posterior zirconia full crown restoration before clinical process improvement; the time required for centralized digital impression production; the comfort level of patients; and the adjacency relationship, occlusal contact relationship, and time required for prostheses adjusting (i.e., whether centralized digital impressions would compromise the quality of pro-stheses and increase the time of prostheses adjusting). RESULTS: The average time to make a traditional impression was (9.98±1.41) min, and the average time required for each patient to make a centralized digital impression was (5.98±1.49) min, which was shorter than that to used make a traditional impression (P<0.05). Centralized digital impression made patients feel more comfortable compared with traditional impression (P<0.05). The adjacency relationship of restorations by centralized digital impression was more appropriate (P<0.05), and no significant difference in occlusal relationship was found (P>0.05). The time required for adjusting prostheses also had no significant differences (P>0.05). CONCLUSIONS Centralized digital impression can improve clinical efficiency for patients undergoing single posterior zirconia crown restoration. The time for impression taking is shorter, and patients feel more comfortable without compromising the quality of the prostheses.
Humans ; Cross-Sectional Studies ; Dental Impression Technique ; Crowns ; Zirconium ; Workflow ; Computer-Aided Design ; Time Factors ; Dental Impression Materials

Achieving precise restoration of tooth function and personalized restoration of natural tooth esthetics has always been a significant challenge in direct restorative dentistry. The traditional direct restorative techniques are limited by the subjective operations of dentists, resulting in high technical sensitivity, long operation time, and unpredictable restoration results, making it difficult to meet patients' personalized demands for restoration outcomes. An innovative flowable resin injection technique was introduced in this study. By combining digital design with personalized restoration guides, this technique achieves precise and personalized tooth restoration, thus revolutionizing the traditio-nal paradigm of direct tooth restoration. Specifically, this technique is guided by the patient's subjective aesthetic needs. It utilizes digital technology to pre-design the restoration result and creates a personalized restoration guide. During clinical operation, the dentist needs to only precisely inject the flowable resin into the guide, allowing for rapid completion of the restoration, thereby significantly reducing the operation time and improving the precision and predictability of the restoration. The perfect combination of digital design and flowable resin injection not only significantly improves the precision and predictability of direct tooth restoration but also remarkably shortens the clinical operation time and reduces the requirements for the dentist's technical level, making it widely applicable to the restoration of various tooth defects. Thus, it improves patient satisfaction and reduces the workload of dentists. This innovative restoration technique is expected to become a new productive force in future clinical direct adhesive restorations.
Humans ; Dental Restoration, Permanent/methods* ; Esthetics, Dental ; Composite Resins ; Computer-Aided Design ; Injections

Occlusal rehabilitation is an effective means of treating tooth wear, edentulous jaws and other oral diseases. Among them, full-mouth fixed occlusal reconstruction can effectively restore aesthetics and function, but the complexity of the clinical process, the high sensitivity of the technique, and the high incidence of various complications have always drawn much attention. With the application and development of digital technology in occlusal rehabilitation, the treatment outcome has been improved compared with traditional treatment. However, there are many kinds of digital technology with different efficacy, how to build an efficiently standardized digital clinical technical solution is a current difficulty. Therefore, combined with the long-term work of the department of prosthodontics in our hospital, in this paper, the minimum (occlusal perception of thickness) and maximum (centric relation) geometric quantities which should be paid attention to during reconstruction are put forward. We systematically organized the clinical procedure of digital full-mouth fixed occlusal rehabilitation used in our department for a long time. In conclusion, a 5-stage 19-step or n-step solution (5-19N for short) characterized by "from large to small" restorative space splitting logic is proposed. It has a certain reference value for the future use of digital technology to deal with complex occlusal rehabilitation cases.
Humans ; Dental Occlusion ; Computer-Aided Design ; Mouth, Edentulous/rehabilitation*

This study explored a novel digital design and fabrication method for a double constrained split orthodontic miniscrew guide to improve the accuracy and safety of clinical miniscrew implantation and reduce related complications. A patient requiring miniscrew implantation was selected, and data were acquired using cone beam computed tomography (CBCT) and intraoral optical scanning. For the construction of a double constrained split guide including a screw-hole guide and an insertion rod guide, different types of software such as Mimics 24.0, Geomagic wrap 2021, and Materialise magics 21.0 were utilized for 3D reconstruction, model integration, and guide design. The guide was then fabricated via laser metal 3D printing. Model and intraoral try-in results demonstrated that the guide fitted well and was stable. Postoperative CBCT verified that the final miniscrew implantation site was consistent with the preoperative design, and no related complications occurred. This double constrained split orthodontic miniscrew guide provides a precise and safe digital solution for clinical miniscrew implantation.
Humans ; Bone Screws ; Cone-Beam Computed Tomography ; Printing, Three-Dimensional ; Orthodontic Anchorage Procedures/instrumentation* ; Imaging, Three-Dimensional ; Computer-Aided Design

Objective: To explore the effect of scanning methods on finish line trueness of the full crown preparation. Methods: The standard full crown preparation model of the right maxillary first molars was prepared by using the maxillary standard resin dentition model. The standard preparation was scanned by imetric scanner and data were used as the true value. CEREC Omnicam and 3Shape TRIOS were used to scan the standard preparation. According to the scanning methods, they were divided into parallel scanning group, occlusal wave scanning group and buccolingual wave scanning group. Each group was scanned repeatedly 6 times. The data were imported into Geomagic Studio 2013 software, and the local finish line image data of the mesial, distal, buccal and lingual regions of the full crown preparation were extracted respectively. Three-dimensional deviation analysis was performed with the reference true value, and the root- mean-square error (RMSE) was the evaluation index of scanning trueness. The statistical method was one-way ANOVA. Results: Parallel scanning group: in general, the RMSE value of complete finish lines of scanner B [(35±6) μm] was significantly lower than that of scanner A [(44±7) μm](P<0.05). After scanner A occlusal wave scanning, the RMSE values of the mesial and distal finish lines [(33±5) and (50±12) μm] were significantly lower than those of parallel scanning group (P<0.05). After buccal and lingual wave scanning, the RMSE values of local finish lines in the mesial, distal, buccal and lingual regions [(37±3), (50±6), (28±6) and (29±8) μm] were significantly lower than those in parallel scanning group [(45±9), (63±7), (38±3) and (40±3) μm] (P<0.05). No significant difference was found in the RMSE values of the mesial, distal, buccal and lingual regions of scanner B between parallel scanning group, occlusal wave scanning group and buccolingual scanning group (P>0.05). Conclusions: The scanning trueness of the full crown preparation finish line obtained by the active triangulation scanning equipment can be improved by changing the scanning method to wave scanning.
Humans ; Imaging, Three-Dimensional ; Dental Impression Technique ; Computer-Aided Design ; Dental Care ; Crowns

Using digital technologies in concurrently performing missing tooth implantation and preparation of remaining teeth is a solution to reduce the number of visits and improve efficiency. This paper proposes a digital process for simultaneously implanting and preparing teeth. It integrates implant surgical guide and 3D-printed tooth preparation guide into a single guide and completes guided implant placement and precise tooth preparation. Based on "repair-oriented" virtual implant planning, the implant surgical guide can improve the efficiency and predictability of implant placement, and its linear accuracy is about 1 mm. The tooth preparation guide precisely guides tooth preparation and restoration space visualization, ensuring the quality of the tooth preparation. The two guides have different design accuracy requirements, and thus their combination improves the overall guiding accuracy requirements. The concurrent application of the two guides minimizes the clinical operation time, number of visits, and economic burden of patients.
Humans ; Surgery, Computer-Assisted ; Dental Implantation, Endosseous ; Printing, Three-Dimensional ; Technology ; Tooth Preparation ; Computer-Aided Design ; Dental Implants ; Imaging, Three-Dimensional ; Cone-Beam Computed Tomography

OBJECTIVE: To investigate the influence of 135° and 90° cavity design on quality of margin and marginal adaptation and microleakage of all-ceramic computer aided design/computer aided manufacturing (CAD/CAM) inlays. METHODS: One hundred extracted human molars were prepared by criteria of buccal occlusal (BO) inlay. On the buccal, the mesial margin was prepared as 135° bevel while the distal margin was prepared as butt-joint. All-ceramic restorations were made in the Sirona CEREC AC CAD/CAM system with VitaBlocs Mark Ⅱ, Upcera UP.CAD, IPS e.max CAD, Upcera Hyramic and Lava Ultimate. The gaps between each inlay's mesial margin-abutment and distal margin-abutment were recorded under an optical microscope. Each inlay was adhered to the abutment and aged by thermal cycling for 10 000 times. Each specimen was cut into 3 slices after staining. Dye penetration was evaluated under an optical microscope for mesial and distal margins. RESULTS: Mean marginal integrity rate, mean marginal gap value and mean depth of microleakage of 135° margin of Group Upcera Hyramic and Lava Ultimate were significantly better than those of Group VitaBlocs Mark Ⅱ, Upcera UP.CAD and IPS e.max CAD(P < 0.05). Mean marginal gap value, mean depth of microleakage and scale of mean depth of microleakage of 90° margin of Group Upcera Hyramic and Lava Ultimate were significantly better than those of Group Upcera UP.CAD and IPS e.max CAD (P < 0.05) while mean marginal integrity rate was not significantly different (P>0.05). Mean marginal integrity rate of 90° margin was significantly better than that of 135° margin in each group (P < 0.05) while mean depth of microleakage between different margins was not significantly different in each group (P>0.05). Mean marginal gap value of 90° margin of Group VitaBlocs Mark Ⅱ and IPS e.max CAD was significantly better than that of 135° margin (P < 0.05) while there was not significant difference in other 3 groups between 90° and 135° margin (P>0.05). Scale of mean depth of microleakage of 135° margin of Group Upcera Hyramic and Lava Ultimate was significant better than that of 90° margin (P < 0.05) while there was not significantly different in other 3 groups between 90° and 135° margin (P>0.05). CONCLUSION The mesial and distal margins of abutement of all-ceramic inlay should be prepared as butt-joint.
Humans ; Aged ; Molar ; Ceramics ; Computer-Aided Design ; Dental Porcelain ; Materials Testing

With the development of computer and digital technology, the application of computer-aided technology has become a new trend in the field of oral implant. Computer-guided oral implant surgery has the advantages of being safer and more accurate than traditional implant surgery, and it can truly realize the concept of restoration-oriented implant. However, computer-guided oral implant surgery has various steps which cause deviations accumulation, so that some clinicians remain sceptical about the accuracy of the technology. Currently, due to the lack of a quantitative system for evaluating the accuracy of computer-guided oral implantation, the implant deviation in each step is still inconclusively in the stage of research and debate. The purpose of this paper is to summarize the advantages and disadvantages, research progress, accuracy and influencing factors of computer-guided oral implantation, aiming to provide a reference for improving implant accuracy and guiding clinical design and surgery.
Computer-Aided Design ; Computers ; Cone-Beam Computed Tomography ; Dental Implants ; Imaging, Three-Dimensional ; Patient Care Planning ; Surgery, Computer-Assisted