Orthognathic surgery, which involve osteotomy and repositioning of the maxillomandibular complex, has recently emerged as a crucial method of correcting dentofacial deformities. The optimal placement of the maxillomandibular complex holds utmost significance during orthognathic surgery because it directly affects the surgical outcome. To accurately achieve the ideal position of the maxillomandibular complex, with the rapid advancements in digital surgery and 3D-printing technology, orthognathic surgery has entered an era of “Precision Surgery” from the pervious “Empirical Surgery.” This article provides comprehensive insights into our extensive research and exploration of the treatment modality known as “precision orthognathic surgery” over the years. We also present the technical system and application in“Ortho+X” treatment modality to offer valuable references and assistance to our colleagues in the field.

Implant treatment in the esthetic area requires stable osseointegration and successful esthetic outcomes. Achieving this goal requires careful consideration of accurate implant axis and ideal three-dimensional position. Owing to the high esthetics and the special anatomical structure of the maxillary, a successful implant means a synthesized deli-beration of the residual bone dimensions, soft-tissue thickness, and the relationship of the residual alveolar ridge with the planned restoration. This article offers an in-depth analysis of the clinical decisions and key factors affecting the implant direction in the esthetic area.

Crown replacement has remained one of the difficult methods for installing fixed prosthesis but is often performed because of aesthetic factors and invasion of biological width. This article focuses on the clinical scenario in which preexisting crown margin has defects. Given that clinical decisions regarding restoration management and perio-dontal tissues have to be made with caution, a decision tree of the decision making process for natural abutments in aesthetic area with preexisting defected crown margin is presented. The re-establishment of a new crown margin is the key to the success of a new restoration, and the new margin should be located at the proper esthetic position and right biological position. It should have fine, smooth, and continuous morphology.

Objective This study aims to analyze and summarize the characteristics of supernumerary teeth by using cone-beam computed tomography (CBCT). Methods A total of 718 patients with 1 138 supernumerary teeth were retrospectively collected. Age, gender, number, location, morphology, eruption status, and accompanying symptoms of the supernumerary teeth were statistically analyzed. The relationship relative to jaws, gender, and eruption status were analyzed and discussed. Results The average age of the patients was 9.54±5.32 years, and the male to female ratio was 2.88∶1. About 77.02% of the patients sought medical advice during the mixed dentition period, and 50.70% had one supernumerary tooth. These supernumeraries were most commonly conical in shape, and 85.76% of them were in the incisor region, 92.09% in the upper jaw, 46.75% in inverted position, and 86.20% unerupted. Overall, 65.29% of them had fully developed roots, and 60.63% had an impact on adjacent structures. Significant differences were found in eruption status, morphology, zoning, direction, root development, and impact on adjacent structures between the supernumerary teeth located in the upper and lower jaws (P<0.05). Significant differences were also detected in gender, morphology, zoning, orientation, root development, and impact on adjacent structures between erupted and unerupted teeth (P<0.05). The incidence of supernumerary teeth in the incisor region was higher in males than that in females. Moreover, the root of supernumeraries was more completely developed in males than in females (P<0.05). Conclusion For supernumerary teeth, CBCT images can provide accurate three-dimensional radiographic data and are valuable for clinical diagnosis and treatment planning.

Objective This study aims to evaluate the correlation between differences in intraoperative jumping gaps and soft tissue changes around immediate implant placement and provisionalization (IIPP) in the maxillary anterior region. Results will provide a basis for clinical evaluation of the change trend and long-term stability of the labial soft tissue contours of patients with different jumping gaps. Methods Thirty-two patients with single tooth loss in the maxillary aesthetic area were enrolled, and they all received immediate implant placement and restoration. All patients were divided into three groups: A, B, and C according to the size of the jumping gap, group A: horizontal defect dimension (HDD) ≤2 mm; group B: 2 mm<HDD≤3 mm; group C: HDD>3 mm. Geomagic studio 2013 was used to quantitatively analyze the contour volume of the soft tissue around the implant and the level of the labial gingival margin. The pink esthetic score (PSE) was used for the final aesthetic evaluation. Results All implants had osseointegration within 6 months after the surgery. The average thickness of soft tissue contour volume changed by 0.62 mm±0.15 mm, and the average PES was 11.09±0.99. The changes in the gingival mucosa levels in the three groups at 6 months after operation were 0.45 mm±0.11 mm, 0.40 mm±0.12 mm, and 0.35 mm± 0.11 mm, respectively. The changes in the average thickness of the soft tissue contour volume in the three groups at 6 months after the operation were 0.77 mm±0.16 mm, 0.63 mm±0.17 mm, and 0.54 mm±0.11 mm. A moderate negative correlation was found between the jumping gap size and the gingival mucosa level, and the average thickness changed. No significant correlation was found between size of jumping gap and PES. Conclusion Although the contour volume of the labial soft tissue continuously decreased within 6 months after IIPP in the maxillary anterior region, the surgical procedure can achieve a satisfactory aesthetic effect, and the level of soft tissue around the implant can be well maintained.

Objective This study aimed to explore the stress distribution of surface-mounted inlays with two ceramic materials and different strategies for fiber post-restoration on pulp-penetrating non-carious cervical lesion in a maxillary first premolar to provide minimally invasive and reasonable restorative methods. Methods The cone beam computed tomography data of the standard right upper first premolar were selected. Healthy control (HC) and defective control (DC) finite element models were established. Then, eight experimental models were established according to two different ceramic materials (IPS e.max CAD [LD] and Lava Ultimate [LU]) and different locations of fiber post (without fiber post [NP], fiber post in buccal root canal [B], fiber post in palatal root canal [P], fiber post in both root canals [BP]), namely, LD_NP, LD_B, LD_P, LD_BP, LU_NP, LU_B, LU_P, and LU_BP. Axial load F1 and lateral load F2 were applied. Maximum principal stress and displacement of the buccal tip were investigated using finite element analysis software. Then, the percentage change of the following indicators in each experimental group was analyzed: stress of defective tip with group DC, stress of enamel and dentine, and displacement of buccal tips with group HC. It was considered similar when the percentage change was less than 5%. Results LD and LU groups could effectively reduce the stress of the defective tip, but the decreasing amplitude in the former was greater than that of the latter. For the stress of surface-mounted inlays and resin adhesive layer, LD groups were higher than LU groups, and no significant difference in stress peak was found among different experimental groups in the same material. In addition, fiber posts in double root canals could significantly reduce buccal tip displacement. Conclusion For pulp-penetrating non-carious cervical lesions, the restorative strategy of surface-mounted inlays could be applied. Compared with Lava Ultimate, IPS e.max CAD could better protect the defective tip tooth. Furthermore, fiber posts in double root canals could decrease overall deformation and increase the retention of surface-mounted inlays.

Periodontitis is a chronic inflammatory disease that destroys the integrity of tooth-supporting tissue. Periodontitis is listed as a major oral disease by the World Health Organization and is a public-health problem affecting global oral and systemic health. The fourth national oral health epidemiological survey has revealed that periodontitis is one of the most common oral problems in China. With the development of science and medicine, increased attention is being paid to the importance of oral health and its influence on general health. Accordingly, stomatologists are required to master more relevant information on clinical diagnosis and treatment, as well as to pay more attention to the diagnosis and treatment methods of patients with different systemic diseases. This article expounds the diagnosis and treatment strategy of patients with systemic disease periodontitis. We aimed to help stomatologists make more reasonable diagnosis and treatment decisions.

Traditionally, vital pulp therapy (VPT) is mainly indicated for young permanent teeth. However, in recent years, VPT has been increasingly applied to mature permanent teeth. VPT was previously thought to be effective only for teeth with normal pulp or reversible pulpitis. However, an increasing body of evidence has demonstrated that VPT can successfully manage permanent teeth with irreversible pulpitis or apical periodontitis. This work discusses which teeth with irreversible pulpitis or apical periodontitis are suitable for VPT, the recommended method to evaluate and select this kind of case, and the clinical procedure involved to operate such a case.

Objective This study aimed to remove occlusal veneers of varied thicknesses and compositions by Er:Yag laser in vitro and analyze the interfacial microstructure between veneers and tooth that irradiated by laser, by which experimental evidence could be provided to support the non-invasive removal of occlusal veneerby laser. Methods Fresh mandibular premolars extracted for orthodontic requirements were collected for tooth preparation. Three kinds of ceramic materials (Vita Suprinity, Vita Mark Ⅱ, and Upcera Hyramic) were selected to fabricate occlusal veneer with different thicknesses (1.0, 1.5, and 2.0 mm). One week later, Er:Yag laser (2.5 W and 3.5 W) was used to irradiate and remove the occlusal veneer and recorded the timespan. After the removal operation, the micro-morphologies of samples were examined by scanning electron microscope. Results Upcera Hyramic veneer failed to be removed (>20 min); the operation span at 2.5 W, Vita Suprinity (96.0 s±16.0 s) was longer than Vita MarkⅡ(84.5 s±19.5 s) in the 1.0 mm group (P<0.05), and Vita Suprinity (246.5 s±13.5 s) was longer than Vita MarkⅡ(170.0 s±14.0 s) in the 1.5 mm group (P<0.05). At 3.5 W, Vita Suprinity (381.0 s±24.0 s) was longer than Vita MarkⅡ(341.5 s±26.5 s) in the 2.0 mm group. Conclusion Increasing laser power could shorten the operation span and facilitate the removal of occlusal veneers with the same thickness and composition. The occlusal veneer was sustained when insufficient laser power was applied. With the same laser power and ceramic thickness, laser penetration could interfere with the integral of the ceramic structure when the laser interacted with the bonding layer. With the same ceramic composition and laser power, the operation span and laser power increased with the thickness of the occlusal veneer. However, the laser was incapable of removing occlusal resin veneer directly.

Zirconia crown has been widely used in the field of prosthodontics. Traditional zirconia exhibits excellent mechanical properties but lacks translucency. The introduction of transparent zirconia significantly enhances its aesthetic performance. In clinical applications, factors affecting the aesthetic results of full zirconia crown should be comprehensively considered, and the most suitable restoration should be chosen. Additionally, clinicians need to design appropriate tooth preparation dimensions and methods based on an individual patient’s actual situation. During the clinical bonding process of zirconia, proper surface treatment of the tooth and restoration is essential. The selection of suitable adhesives is crucial for achieving optimal bonding strength and aesthetics.

Orthodontics is a discipline that is based on aesthetics. It coordinates the relationship among nose, lip, and chin through the movement of teeth and the adjustment of jaw relationship. Orthodontists need to fully analyze the patient’s soft tissue profile before treatment. They also need to analyze the existing problems and those that may be solved or caused during orthodontics to guide the design of orthodontic treatment and effectively improve the clinical effect of orthodontics. This article reviews the aesthetic preconditions that guide the design of orthodontic treatment from the perspective of orthodontists.

In the field of prosthodontics, the use of virtual patients for biomimetic restoration holds great promise for various applications. Virtual patients consist of digitized data that encompasses details on the morphology, structure, and spatial relationships within the maxillofacial and intraoral regions. Nonetheless, there are several challenges associated with acquiring digital data, achieving accurate alignment, and recording and transferring dynamic jaw movements. This paper aims to concentrate on the process of constructing virtual patients, highlight the key and challenging aspects of virtual patient construction, and advocate for the extensive adoption and utilization of virtual patient technology.

Objective This study aimed to observe the outcomes of iRoot BP Plus full pulpotomy in primary molars with partial irreversible pulpitis retrospectively. Methods Collect 102 cases of primary molars with partial irreversible pulpitis undergoing iRoot BP Plus full pulpotomy from January 2019 to August 2023, with a follow-up period of 24-47 months. Based on the presence of irreversible pulpitis symptoms before surgery, the included cases will be divided into asymptomatic group (n=53) and symptomatic group (n=49). Observe the clinical and imaging success rates of both groups. Results Clinical success rates were 96.2% and 97.9% in asymptomatic and symptomatic groups, and radiographic success rates were 96.2% and 93.9% respectively. Conclusion iRoot BP Plus full pulpotomy can be used for the treatment of primary molars with partial irreversible pulpitis under an enhanced pulpotomy protocol.

With the development of periodontal regenerative technology, an increasing number of scholars reported that advanced periodontitis involving teeth can be preserved through intentional replantation. Intentional replantation has become the last possible method to preserve natural teeth for advance periodontitis with signs of tooth extraction. However, the indications of intentional replantation are strict, and the success of the operation is closely related to the condition of cases and the operation skills of doctors. In this article, the operation steps and criteria of intentional replantation were summarized by introducing three success cases of advanced periodontitis involving teeth preserved by intentional replantation. The relevant factors that affect the prognosis of intentional replantation in advanced periodontitis involving teeth preservation were analyzed to help clinicians preserve natural teeth.

At present, the commonly used clinical protocols of oral cosmetic restoration are mostly based on the oral aesthetic indexes proposed by Western developed countries (referred to as Western aesthetics), which are different from the oral aesthetic indexes unique to Chinese people (referred to as Chinese aesthetics). In the design of restoration schemes and the evaluation of restoration effects, these differences have a large or small effect on the doctor-patient-technology triad. Improper handling could directly weaken the cooperation efficiency of the three parties, reduce patient satisfaction, and even lead to medical disputes in serious cases. From doing a good job of oral cosmetic restoration in China, the connotative characteristics of Chinese oral aesthetics are introduced in this paper, and the value of oral aesthetic analysis in diagnosis and treatment is discussed. The process and method of aesthetic analysis and assessment through the modified Chinese psychosocial impact of dental aesthetics questionnaire and the evaluation ruler of the expected value of oral cosmetic restoration are further introduced in detail.

Pregnancy is a special period for developing and treating oral diseases. Oral emergencies during pregnancy need to be handled appropriately. Changes in the physiological environments and personal habits of pregnant women increase susceptibility to some oral diseases. However, clinical treatment strategies are limited due to the need to ensure the safety of pregnant women and fetuses. Pregnant women should obtain oral health knowledge and enhance their awareness. Dentists should adhere to the principle of “prevention before pregnancy, controlling symptoms during pregnancy, and treating diseases after pregnancy” for different pregnancy periods. They should also formulate appropriate treatment plans to control emergencies, prevent disease progression, and avoid harmful effects on pregnant women by using the safest, simplest, and most effective strategies that avoid adverse effects on fetuses. Pregnant women and dentists should combine prevention and treatment while collaborating in maintaining oral health during pregnancy. This article focuses on the principles of treatment during pregnancy, and the treatment timing, clinical management, and treatment strategies of different diseases causing oral emergencies during pregnancy are reviewed.

At present, the commonly used clinical protocols of oral comestic restoration are mostly based on the aesthetic indicators proposed by Western developed countries (referred to as Western aesthetics). Mechanically copying the Western aesthetic scheme, ignoring the difference between it and the Chinese oral aesthetic indicators (referred to as Chinese aesthetics), is unable to effectively support personalized cosmetic restoration diagnosis and treatment. In addition, new technologies and new solutions for cosmetic restoration, which are developing rapidly in recent years, are emerging one after another, but many popular concepts are confusing and lack of proper hierarchical diagnosis and treatment norms, and there is indeed an urgent need for discussion and clarity. From the perspective of serving clinical application, this paper discusses the deficiencies of the Chinese translation of the word “aesthetics”, the diffe-rence and connection between aesthetics and cosmetology, and the relationship between cosmetic restoration and fixed restoration. It also discusses the difference between anterior teeth, esthetic zone and exposed zone, the diagnostic and therapeutic value of oral aesthetic analysis, as well as the application methods of desensitization, suggestion, and other therapies in difficult oral cosmetic restoration cases. We further introduce the decision tree and the clinical pathway for restoration and reconstruction of teeth in exposed zone guided by aesthetic analysis, and introduce the clinical process of aesthetic analysis and evaluation, the clinical triclassification of oral cosmetic restoration, and the corresponding clinical classification diagnosis and treatment points.

Objective This study aimed to compare the differences among four kinds of mechanical Ni-Ti files including T-Flex, Reciproc Blue (RB), ProTaper Gold (PTG), and ProTaper Universal (PTU) in dentinal microcrack generation after root canal preparation in vitro by using micro-computed tomography (micro-CT) analysis. Methods A total of 32 freshly extracted double-root-canal premolars with an angle not exceeding 10° were selected and established as root canal preparation models in vitro. Then, the specimens were randomly assigned to four experimental groups (n=8) according to the different Ni-Ti systems used for root canal preparation: group T-Flex, group RB, group PTG, and group PTU. The voxel size of the micro-CT was set at 17.18 μm. Pre- and post-operative cross-sectional images of roots (n=56 940) were scanned and analyzed to identify the presence of dentinal microcracks. The results of each group were expressed by the quantity and percentage of sectional images with microcracks. McNemar test was used to determine whether a significant difference existed in the existence of dentinal microcracks before and after instrumentation. The level of significance was set at P<0.05. Results Overall, 11.04% of the images presented dentinal defects (n=6 288). Dentinal microcracks were observed in 9.82%, 10.79%, 12.27%, and 11.25% of the post-instrumentation images from groups T-Flex, RB, PTG, and PTU, respectively. However, all these dentinal microcracks were already present in the corresponding pre-operative images. No new microcrack of premolars were generated after the root canal preparation utilizing the aforementioned systems. Conclusion Denti-nal microcracks already existed in advance in extracted teeth before root canal preparation. Root canal preparation using the T-Flex, RB, PTG, and PTU systems did not induce the formation of new dentinal microcracks on the straight root canals of premolars.

Complicated crown root fracture is a serious combined fracture of the enamel, dentin, and cementum in dental trauma. The treatment method is complicated. During the procedure, the condition of pulp, periodontal, and tooth body should be thoroughly evaluated, and a multidisciplinary approach combined with sequential treatment is recommended. This case reported the different treatment and repair processes of one case of two affected teeth after complicated crown root fracture of upper anterior teeth, including regrafting of broken crown after flap surgery at the first visit, direct resin repair to remove broken fragments, and pulp treatment and post-crown repair at the second visit. After 18 months of follow-up, the preservation treatment of the affected teeth with complicated crown root fracture was achieved. Therefore, fragment reattachment and post-crown restoration are feasible treatment options for children with complicated crown root fracture.

Robotic surgery is known as the “third technological revolution” in the field of surgery, and is an important milestone in the development of modern surgery. However, our country’s innovative surgical robot industry is still in its early stages, and it is only being utilized in certain surgical fields. To explore the effectiveness of the application of domestic surgical robot in oral and maxillofacial surgery, the author successfully completed a case of benign parotid tumor resection with the assistance of a domestic autonomous robot. The operation was successful, facial nerve function was preserved, and postoperative wound healing was good.

Objective To solve the current problems of loosening and dislodging caused by the high elastic modulus of solid implants, we attempted to study a gradient porous dental implant that can lower the stress concentration and reduce the elastic modulus. Methods SolidWorks software was utilized to design the abutment and mechanical structure of the gradient porous implant. The mechanical properties of the gradient porous implant were evaluated by an orthogonal experimental design from four aspects: pore shape, pore diameter, porous layer height, and circumferential distribution. ANSYS software was used to evaluate the distribution of Von-Mises stress in the implant and its surrounding bone tissues under different structural combination parameters to derive the optimal combination of gradient porous implant parameters. Results The effects of the four factors, namely, pore shape, pore diameter, porous layer height and pore distribution, on the maximum Von-Mises stress on the implant were as follows. As the pore shape became smaller and the circumferential distribution decreased, the Von-Mises stress decreased significantly. The pore diameter went from 500 μm to 600 μm and then to 700 μm. The Von-Mises stress decreased and then increased. It increased with the increase in the height of the porous layer. Conclusion The final optimal combination of parameters for the gradient porous implant was as follows: square pore shape, pore diameter of 600 μm, porous layer height of 3 mm, and quadratic step in pore distribution.

Objective The machine learning algorithm was used to construct a prediction model of children’s dental caries to determine the risk factors of dental caries in children and put forward targeted measures and policy suggestions to improve children’s oral health. Methods Stratified cluster random sampling was adopted in this study. In accordance with different policies and measures in Sichuan Province, 12-year-old students from 3-4 middle schools in eight cities of Sichuan Province were randomly selected for questionnaire survey, oral examination, and physical examination. Multivariate logistic regression analysis of risk factors for dental caries in 12-year-old children was conducted. The dataset was randomly divided into training set and validation set at a ratio of 7∶3. Four machine learning algorithms, including random forest, decision tree, extreme gradient boosting (XGBoost), and Logistic regression, were constructed using R version 4.1.1, and the prediction effects of the four prediction models were evaluated using the area under receiver operating characteristic curve (AUC). Results A total of 4 439 children aged 12 years were included in this study. The incidence of permanent teeth caries was 50.93%. The results of multivariate logistic regression analysis showed that body mass index, highest educational background of the father, highest educational background of the mother, whether to brush teeth, how many times a day, use of toothpaste when brushing teeth, duration of brushing teeth, mouthwash after meals, eating before going to bed after brushing teeth, sweet drinks, snacks, going to dental clinic to examine teeth, and age of brushing teeth were the factors influencing children’s dental caries (P<0.05). The AUC values predicted by random forest, decision tree, Logistic regression, and XGBoost were 0.840, 0.755, 0.799, and 0.794, respectively. In the random forest model, the variable with the highest contribution was eating before bed after brushing. Conclusion A prediction model of dental caries in children was established on the basis of random forest, showing good prediction effect. Taking preventive measures for the main factors affecting the occurrence of dental caries in children is beneficial.

Postoperative infection is one of the most common complications of tooth extraction. It may manifest as localized infection or develop to systemic infection. Clinically, oral surgeons can prevent postoperative infections by urging patients to strengthen oral hygiene, applying antibiotics in a rational and compliant manner, and choosing appropriate surgical methods for tooth extraction. For the treatment of infection, the oral surgeon should formulate a response strategy on the basis of different diagnoses. For local infections such as dry socket, delayed alveolar osteitis, gap infection, and marginal osteomyelitis of the jaws, the infection can be controlled by local debridement, therapeutic use of antibiotics, and incise and drain if necessary. For patients suspected of necrotizing fasciitis, timely extensive debridement should be made to reduce the area of tissue necrosis. For those who have received radiotherapy or anti-resorptive drugs, tooth extraction should follow the recommendations of the relevant clinical guidelines or expert consensus to minimize the risk of osteonecrosis of the jaws. For patients with poor systemic health or dysfunction of the immune system, attention should be paid to identifying infective endocarditis and intracranial infection to ensure the life safety of patients. In this study, the author intends to combine literature review and clinical experience to tackle postextraction infection and its prevention to provide a reference for colleagues on oral and maxillofacial surgery.

Anterior diastema is a common esthetic defect in China. The general treatment for a patient with diastemata, including orthodontics and direct and indirect restorations, is a multidisciplinary clinical procedure covering the orthodontics, operative dentistry, general dentistry, and prosthodontics department. Given the diversity of departments and the complex etiology of this defect, decision-making regarding the closing methods and time selection is undefined and unintegrated, which makes the long-term stability of closure unpredictable. This article proposed an etiology-based decision tree with actual measurement of diastemata width for diastemata closure. The decisional steps include classifying the etiological factors based on patients' medical history and clinical manifestation to evaluate the stability of diastemata. After maintaining the stability of diastemata, contemporary and multidisciplinary treatment plans were selected in accordance with the measured width of diastemata and patients' cosmetic psychology, economics, and available time. These decision trees focus on the challenges of collaboration among dental departments, propose an objective and efficient ways for connections, and promote efficient and effective diastemata closure.

Biodegradable magnesium-based metal-guided bone regeneration (GBR) membranes possess excellent mechanical properties, biodegradability, and osteopromotive capabilities, making them ideal implants for the treatment of maxillofacial bone defects. This review summarizes the current status and future research trends related to magnesium-based GBR membranes. First, the research history and application fields of magnesium-based metals are introduced, and the advantages of the use of magnesium-based materials for GBR membranes, including their mechanical properties, biocompatibility, osteopromotive performance, and underlying mechanisms are discussed. Finally, this review addresses the current limitations of magnesium-based GBR membranes and their applications and prospects in the field of dentistry. In conclusion, considerable advancements have been in fundamental and translational research on magnesium-based GBR membranes, which lays a crucial foundation for the treatment of maxillofacial bone defects.

To keep or extract severe periodontitis damaged teeth is one of the controversial topics in the dentistry from ancient times to present. From different perspectives, professions, technologies, time, and economics, there may be different choices with unidentified consensus. Based on the author’s own understanding, experience, literature review, and other aspects, this article proposes some exchange views on influencing factors, abandoning consideration, preserving possibility, and how to detect and prevent the development of lesions. The aim is to stimulate more thinking and accumulate clinical evidence-based data among peers, in order to facilitate cooperation and promote oral health.

Objective The aim of this study was to demonstrate a novel jaw position adjustment technique derived from digital twins and evaluate the application effect of digital technology-assisted optimization in the process of adjusting jaw position on patients with temporomandibular disorders (TMD). Methods A total of 74 patients with TMD who attended the Department of Temporomandibular Joint, West China Hospital of Stomatology, Si-chuan University, between June 2022 and May 2023 were selected. The patient’s initial computed tomography (CT) and bilateral temporomandibular joint data obtained by magnetic resonance imaging (MRI) were collected. The 148 joints were divided into the normal disc-condyle relationship (N) group, disc displacement with reduction (DDWR) group, and disc displacement without reduction (DDWoR) group. Assisted by digital technology, the patient’s CT data were reconstructed, and a personalized reference plane was established to adjust the jaw position. A three-point bite guiding splint was designed by the adjusted occlusal space and then fabricated by 3D printing technology. It was worn by the patients and then reviewed by MRI. Before and after the adjustment of jaw position, the amount and direction of condyle and disc displacement and the angle between condyle and disc were measured as the evaluation indexes of the effect of the adjustment. The correlation with condylar displacement was evaluated. Results In the N group, the disc moved backward and downward along the X and Z axes by (-0.60±0.62) and (0.51±0.71) mm, respectively. In the DDWR group, the disc moved backward and upward along the X and Z axes by (-1.33±1.38) and (-0.09±1.31) mm, respectively. In the DDWoR group, the disc moved forward and downward along the X and Z axes by (0.49±1.76) and (1.35±1.76) mm, respectively. The angle between the condyle and the disc decreased after adjustment of the jaw position in all three groups. All patients showed improvement in symptoms after adjustment. Conclusion Digital technology-assisted jaw position adjustment can simplify the process, reduce the sensitivity of the technique, and improve patients’ disc-condyle structure and symptoms. Therefore, its application in the treatment of patients with TMD is of great clinical significance.

Facial nerve training can prevent facial expression muscle atrophy and promote the recovery of facial para-lysis in patients with peripheral facial paralysis. However, there is still a lack of specific and unified technical standards for facial nerve training, which results in a variety of clinical training methods and uneven levels. In order to standardize the application of facial nerve function training technology for nursing staff, the study convened relevant domestic experts, based on evidence-based combination with the disease characteristics of peripheral facial paralysis and expert clinical experience, conducted in-depth interviews with experts, expert correspondence and expert meetings, and finally formulated the expert consensus on facial nerve function training in patients with peripheral facial paralysis. Overall, suggestions for standardizing the timing, training methods, evaluation methods, health education and other aspects were provided for clinical reference.

Objective To address the quality problems caused by high porosity in the preparation of dental cobalt-chrome alloy prosthetics based on selective laser melting (SLM) technology, we investigated the influence mechanism of different forming process parameters on the microstructure and properties of the materials. Moreover, the range of forming process parameters that can effectively reduce defects was precisely defined. Methods The effects of laser power, scanning speed, and scanning distance on the pore properties, surface roughness, and hardness of dental cobalt-chrome alloy were investigated by adjusting the printing parameters in the process of SLM. Through metallographic analysis, image analysis, and molten pool simulation, the pore formation mechanism was revealed, and the relationship between the porosity and energy density of SLM dental cobalt-chrome alloy was elucidated. Results When the linear energy density was higher than 0.18 J/mm, the porosity defect easily appeared at the bottom of the molten pool. When the laser energy density was lower than 0.13 J/mm, defects occurred in the gap of the molten pool due to insufficient melting of powder. In particular, when the linear energy density exceeded the threshold of 0.30 J/mm or was below 0.12 J/mm, the porosity increased significantly to more than 1%. In addition, we observed a negative correlation between free surface roughness and energy density and an inverse relationship between macroscopic hardness and porosity. Conclusion On the basis of the conditions of raw materials and molding equipment used in this study, the key process parameters of SLM of molding parts with porosity lower than 1% were successfully determined. Specifically, these key parameters included the line energy density, which ranged from 0.13 J/mm to 0.30 J/mm, and the scan spacing should be strictly controlled below 90 μm.

Objective This study aims to explore the status quo of health literacy and quality of life in elderly patients with chronic periodontitis and determine their correlation to understand the influencing factors of health literacy and quality of life. Methods A total of 150 elderly patients with chronic periodontitis were investigated using the general information questionnaire, Oral Health Literacy-Adult Questionnaire, and Oral Health Impact Profile for Chronic Periodontitis. Results The total scores of health literacy and quality of life of elderly patients with chronic periodontitis were 6.59±4.11 and 29.25±9.42, respectively. The total score of health literacy was negatively correlated with the total score of quality of life (r=-0.234, P<0.01). Regression analysis showed that age, place of residence, education level, and disease understanding were the influencing factors of health literacy. Family history, smoking, and education level were the influencing factors of quality of life. Conclusion The health literacy level of elderly patients with chronic periodontitis is insufficient, and their quality of life needs to be improved. Improving the health literacy of patients is an effective way to improve their quality of life. Nursing staff must formulate corresponding health education strategies to improve the health literacy of patients and improve their quality of life.

Objective This study aims to investigate the correlation between serum Galectin-3 levels and the risk of periodontitis in patients with type 2 diabetes mellitus (T2DM). Methods A total of 140 patients with T2DM admitted to the endocrinology department of Weifang People’s Hospital, Affiliated to Weifang Medical College from July 2021 to November 2022 were selected and divided into T2DM without periodontitis group (T2DM group, n=67) and T2DM with periodontitis group (T2DMP group, n=73) according to whether they were combined with periodontitis. In the same period, 65 non-periodontitis volunteers with normal blood glucose were selected as healthy control group (NC group). Blood samples of all subjects were collected, and serum Galectin-3 levels and related laboratory indices were detected and compared among the three groups. Results Serum Galectin-3 levels in the NC, T2DM, and T2DMP groups were 3.81 (3.49, 4.15), 4.82 (4.25, 5.26), and 6.83 (5.19, 7.28) ng/mL, respectively. After adjusting for the influence of baseline data by multiple linear regression, serum Galectin-3 levels in the T2DMP and T2DM groups were significantly higher than those in the NC group (all P<0.05). Multiple linear regression analysis showed that serum Galectin-3 levels were positively correlated with homeostatic model of the insulin resistance index (β=0.254, 95%CI:0.089-0.419, P=0.003), glycosylated hemoglobin A1c (β=0.397, 95%CI: 0.049-0.745, P=0.026), and clinical attachment loss (β=0.298, 95%CI: 0.024-0.572, P=0.033). After adjusting for the effects of covariates, binary logistic regression showed that serum Galectin-3 levels were significantly associated with the risk of periodontitis in patients with T2DM (OR=2.146, 95%CI: 1.260-3.655, P=0.005). Trend test showed that the risk of periodontitis in patients with T2DM increased with increasing serum Galectin-3 levels (P_trend=0.011). Receiver operating characteristic (ROC) curve analysis showed that the area under the curve (AUC) of serum Galectin-3 in predicting T2DM periodontitis was 0.861 (95%CI: 0.801-0.920, Z=11.806, P<0.001). Conclusion Serum Galectin-3 levels were elevated in patients with T2DM and pe-riodontitis and associated with the risk of periodontitis.

Stevens-Johnson syndrome (SJS), also known as the multifactorial erythematous drug eruption, is a class of adverse reactions of the skin and mucous membranes primarily caused by drug allergy often involving the oral cavity, eyes, and external genital mucosa, generally accompanied by fever, and can be life-threatening in severe cases. In February 2022, the Department of Stomatology, the First Affiliated Hospital of Zhengzhou University admitted a patient with huge inflammatory hyperplasia of bilateral lingual margins secondary to SJS. Upon admission, no other obvious symptoms were observed except for tongue hyperplasia. The patient suffered from a severe adverse drug reaction caused by acetaminophen 2 months ago and was complicated by liver dysfunction and pulmonary infection. After 1 month of treatment and rehabilitation, he developed a secondary tongue mass and was subsequently admitted to Dept. of Oral and Maxillofacial Surgery Ward 2, the First Affiliated Hospital of Zhengzhou University. After completing the examination, the tongue mass was surgically removed. After a follow-up of 11 months, the patient’s condition was satisfactory and no temporary discomfort was observed. The case of tongue mass secondary to SJS is extremely rare. If a stomatologist encounters a similar case, we should carefully inquire about the drug allergy history and recent medication history, and be alert to whether or not they had adverse drug reactions recently.

Objective This study aims to compare the sedative effects of remimazolam and midazolam during impacted tooth extraction to provide a comfortable sedation treatment for patients with dental anxiety. Methods A prospective randomized controlled trial was conducted, in which 60 patients undergoing intravenous sedation for mandibular impacted third molar extraction were evenly divided into either the remimazolam or midazolam group. Prior to receiving a nerve blocker, the patients were sedated with remimazolam or midazolam. Various parameters were recorded and analyzed, including onset time, awakening time, recovery time, modified dental anxiety scale (MDAS) scores before and after surgery, patient-doctor satisfaction levels, postoperative side effects within 24 hours, heart rate (HR), and mean arterial pressure (MAP) at different time points. Results Compared with the midazolam group, patients in the remimazolam group demonstrated significantly shorter onset, awakening, and recovery times as well as lower postoperative MDAS scores and higher levels of patient-doctor satisfaction. Fewer postoperative side effects were reported in the remimazolam group, although the differences were not statistically significant. Conclusion The use of remimazolam demonstrates faster onset and recovery, superior efficacy in reducing dental anxiety, and enhanced satisfaction among patients and doctors, thereby presenting distinct advantages for sedation treatment for patients with dental anxiety.

Langerhans cell histiocytosis (LCH) is a group of unexplainable abnormal proliferation and aggregation of Langerhans cell. LCH can be classified into four clinical variants: Letterer-Siwe disease, Hand-Schüller-Christian disease, eosinophilic granuloma, and congenital self-healing LCH. LCH is most prevalent in children. Lesions can be localized in a single system or multiple organs, and clinical manifestations vary depending on the affected organs. The skin and mucocutaneous tissues are the starting point of the affected tissue. This study presents a LCH case characterized by transient self-healing. This case can further provide references for the clinical diagnosis and treatment of LCH.

Objective This study aims to observe the clinical effect of bone plate reduction in combination with a resorbable plate on large mandibular cysts. Methods Between October 2017 and September 2022, patients with large mandibular cysts in the presence of labial and buccal cortical bone were involved in the study. Intraoral approach was performed for bone plate reduction. Cone beam computed tomography (CBCT) scan was reviewed at 3, 6, and 9 months postoperatively to observe postoperative complications. Osteogenic results were assessed at these times to determine the clinical outcomes of this procedure. Results Eleven cases with large mandibular cysts in the presence of cortical bone were evaluated. The average thickness of the cortical bone on the labial and buccal sides was measured to be about (1.98±0.37) mm before surgery, with a mean value of (0.73±0.17) mm at the thinnest part of the plate and up to 0.51 mm at the thinnest part of the plate. The cystic cavities were well revealed during the surgeries, which were completed successfully. Postoperatively, the wounds healed in one stage without infection. The percentages of cyst shrinkage were 20.01%, 41.76%, and 73.41% at 3, 6, and 9 months after surgery, respectively. Quantitative measurement of bone mineral density in the jaws by CBCT with MIMICS software. The bone mineral densities of the adult bone were 313.78, 555.85, and 657.45 HU at the 3, 6, and 9 month time intervals, respectively. No significant change in the patient’s maxillofacial appearance were observed from the preoperative period as assessed by the patient’s and observer’s visual analog scale. Conclusion Bone plate reduction is an effective treatment for large mandibular cysts of the oral and maxillofacial region with the presence of cortical bone.

Objective This work aimed to evaluate the effect of artificial aging on the translucency and color difference (ΔE) of ultra-translucent zirconia and provide a reference for clinical application. Methods The discs of ultra-translucent zirconia from six brands (Wieland, 3M ESPE, Amann Girrbach, Kuraray Noritake, Upcera, and Besmile) were cut and sintered according to each manufacturer’s product instructions; the experimental groups were named ZNT, LVP, AG, KAT, UPC, and BSM, respectively. IPS e.max Press was used as the control group (PLT). The specimens (n=6) were prepared with a diameter of 14 mm and a thickness of 1 mm. The specimens were subjected to artificial aging treatment according to the following conditions: in an autoclave at 134 ℃ at 0.2 MPa for 4, 8, and 12 h. According to the CIE1976Lab system, the CIE L*, a*, and b* values of the specimens before and after aging were measured by a co-lorimeter. The translucency parameter (TP) and ΔE were calculated. Results The mean TP values of each group before aging inorder were PLT>KAT>AG>ZNT>BSM>UPC>LVP. We found no significant difference in translucency in all experimental groups after aging for 4 and 8 h compared with those before aging. After 12 h of aging, the TP values of the KAT and ZNT groups were not significantly different from those before aging, but the TP values of the AG, BSM, LVP, and UPC groups were significantly lower than those before aging (P<0.05). The TP value of the control group was significantly higher than that of the other experimental groups at different stages (P<0.05). ΔE=3.3 was considered the visible color difference, and ΔE was less than 3.3 in all groups after 4 h of aging. After aging for 8 h, ΔE of the UPC group was slightly higher than 3.3. ΔE of the BSM and UPC groups was greater than 3.3 after 12 h of aging. Conclusion The TP and ΔE of different brands of ultra-translucent zirconia may change after various aging times. The translucency of some zirconia showed a decreasing trend and the color difference showed an increasing trend with the aging time.

Objective This study aims to understand the prevalence and treatment status of dental caries in preschool children aged 3-5 years in China among the past five years. Methods Databases including CNKI, WanFang data, VIP, MEDLINE, EMBASE were systematically searched for the epidemiological literature of dental caries in preschool children in China from 2017 to 2022 for Meta-analysis. Subgroup analysis was carried out by sex, age, geographical region, ethnology, and residence. Results The Meta-analysis enrolled 27 literatures, including 72 788 preschool children; of which, 38 344 children had dental caries. The merged prevalence of dental caries in preschool children was 59.3% (95%CI: 54.6%-63.9%), and the merged filling rate of caries was 5.7% (95%CI: 2.5%-8.8%). In the subgroup analysis, the merged prevalence rates of caries in children aged 3, 4, and 5 years were 46.9% (95%CI: 42.5%-51.4%), 59.0% (95%CI: 55.1%-62.8%), and 67.3% (95%CI: 62.5%-72.2%), respectively, and the difference was significant. In addition, significant differences were found among different regions. The merged prevalence of dental caries in preschool children was the highest in northwest China (68.6%, 95%CI: 55.5%-81.8%) and the lowest in central China (49.1%, 95%CI: 47.3%-51.0%). The merged prevalence of dental caries was not significantly different among preschool children of different genders, ethnicities, and residence. Conclusion The prevalence of dental caries in preschool children aged 3-5 years in China is high and continuously increases. The oral health of preschool children should be comprehensively strengthened, and a three-level strategy should be implemented to prevent diseases.

Objective This study aims to investigate bond strength between zirconia and resin cement through surface treatments with Er: YAG laser, Nd: YAG laser, and Si-Zr coating. Methods Seventy-five round pre-sintered zirconia discs with a diameter of 18 mm and a thickness of 1.5 mm were prepared by a powder compactor. Fifty discs were randomly divided into five groups of 10 discs each and were subjected to five surface treatments: no treatment (control group), sandblasting with alumina particles (sandblasting group), Er: YAG laser treatment (Er: YAG laser group), Nd:YAG laser treatment (Nd: YAG laser group), and Si-Zr coating treatment (Si-Zr coating group). The discs were then bonded to composite resin columns with resin cement. The shear bond strength of each group was tested with a universal tester. Roughness tester, scanning electron microscope (SEM), and energy dispersive spectroscopy were used to analyze surface performance. Results The bond strength of the Si-Zr coating group was higher than that of the remaining groups (P<0.05). The difference in bond strength between the sandblasting group and the Er: YAG laser group was not statistically significant (P>0.05), but both of them had higher bond strength than the Nd: YAG laser group (P<0.05). The Si-Zr coating group had the highest surface roughness (P<0.05). The surface roughness of the sandblasting, Er: YAG laser, and Nd: YAG laser groups was higher than that of the control group (P<0.05), but the difference among the three groups was not statistically significant (P>0.05). SEM observations showed irregular scratches on the surface of the sandblasting group and large pits with holes on the surface of the Er: YAG and Nd: YAG laser groups. In the Er: YAG laser group, the crystal structure was replaced by a smooth surface with a large amount of microcracks due to partial melting. Complex porous structures that comprised “island-like” structures and mass pores among the grains were observed on the surface of the Si-Zr coating. Only Zr, O, and Y were detected on the surfaces of the control, Er: YAG laser, and Nd: YAG laser groups. Al was found on the surface of the sandblasted group, and a higher proportion of Si was detected on the surface of the Si-Zr coating group. Conclusion Er: YAG laser and Nd: YAG laser treatment on the zirconia ceramic surface could increase roughness and improve the bond strength to resin cement. Si-Zr coating treatment is an effective alternative for increasing the roughness and bond strength of zirconia surface and is superior to sandblasting and laser treatments.

Objective The aim of this study was to evaluate the effects of collagen modification on the osteogenic performance of different surface-modified titanium, including alkaline etching, alkaline etching followed by silanization, and alkaline etching followed by dopamine modification. The proliferation, adhesion, and osteogenic differentiation abilities of MC3T3-E1 cells on the surfaces with collagen modification were analyzed and compared. Methods Collagen was immobilized on the surfaces of pure titanium (Ti-C), alkaline-etched titanium (Ti-Na-C), alkaline-etched and silanized titanium (Ti-A-C), and alkaline-etched and dopamine-modified titanium (Ti-D-C), with pure titanium (Ti) as the control group. The surface morphology was observed by scanning electron microscopy (SEM), and the surface elemental composition was analyzed by X-ray photoelectron spectroscopy (XPS). Contact angle measurements were conducted to evaluate the hydrophilicity of the surfaces. MC3T3-E1 cells were cultured on the surfaces, and their proliferation, adhesion, and osteogenic differentiation abilities were assessed using CCK-8 assay, laser scanning confocal microscope, alkaline phosphatase (ALP) staining, Alizarin red staining and quantitative analysis, as well as real-time quantitative polymerase chain reaction (RT-qPCR) to evaluate the mRNA expression levels of osteogenic-related genes, including ALP, typeⅠcollagen (COL-1), osteocalcin (OCN), osteopontin (OPN). Results SEM and XPS results confirmed the successful immobilization of collagen on the titanium surfaces, with the Ti-Na-C group exhibiting a higher amount of collagen modification. Contact angle measurements showed improved hydrophilicity of the surfaces after collagen modification. CCK-8 results indicated good compatibility of the materials with MC3T3-E1, with enhanced cell proliferation on the collagen-modified surfaces. Cell fluorescence staining revealed better cell spreading on the collagen-modified surfaces, and ALP and Alizarin red staining results suggested that the Ti-Na-C group exhibited the best osteogenic performance, with significantly higher absorbance values in the Alizarin red quantification analysis. RT-qPCR analysis showed that the Ti-Na-C group had the highest expression of the osteogenic-related gene OPN. Conclusion Among the different collagen modification approaches employed in this study, collagen modification on alkaline-etched titanium surfaces showed the most conducive effects on MC3T3-E1 cell adhesion, spreading, proliferation, and osteogenic differentiation. This approach can be considered as the optimal collagen modification strategy for enhancing osteogenesis on titanium surfaces.

Objective This study aimed to compare the effectiveness of ultrasound and acoustic and laser cleaning of curved root canals. Methods A total of 92 molars with independent root canals with a curvature of 20°-40° were prepared and standardized at 04 25# and stained with gentian violet solution for 72 h. Among them, 52 were randomly divi-ded into four groups for final rinsing (n=13): NI group, PUI group, EDDY group, and PIPS group. Ten samples in each group were cut horizontally along the long axis perpendicular to the root and divided into curved upper, curved, and apical segments. Images were taken with a stereomicroscope and Image J measurements were taken to calculate the depth of rinse penetration. The remaining three samples from each group were split along the long axis of the dentin, photographed by scanning electron microscope to record the dentin tubule exposure and staining layer, and scored for staining layer by double-blind method. SPSS 26.0 software was used to perform statistical analysis and select the best flushing method. An extra 40 samples were randomly divided into four groups for detection of flushing fluid penetration depth (n=10): 10, 20, 30, and 40 s. Results In the upper part, the mean depth of infiltration was not significantly different between the experimental and control groups (P>0.05). The PIPS group had a significantly lower smear layer score than the control group and the EDDY group (P<0.01). In the curved segment, the mean depth of infiltration was significantly greater in the PUI group than in the control group (P<0.05); the tarnish layer score was lower in each experimental group than in the control group. At the top, the mean depth of infiltration was greater in the PUI and PIPS groups than in the control group (P<0.05), and the smear layer score was lower in the PIPS group than in the other groups (P<0.05). After the time was changed, the depth of infiltration of PUI increased only in the apical segment as the flushing time increased. Conclusion The PUI and PIPS methods facilitate the penetration of irrigation solution into the dentin canal in curved root canals, especially in the apical segment. The PIPS technique is effective in removing the smear layer in curved root canals.