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.

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.

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.

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 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.

Root canal therapy is the primary treatment method for pulpal and periapical diseases. Various advanced endodontic instruments for mechanical preparation have been marketed. The emergence of nickel-titanium rotary instruments has greatly improved the efficiency of root canal preparation. New demands have been put forward for nickel-titanium rotary instruments as a result of the deepening of clinicians’ awareness of root canal anatomy system as well as the purpose and prognosis of root canal treatment. These clinical-oriented demands accelerate instrument reform and innovation. This work presents new marketed nickel-titanium systems and discusses the advantages and limitations of these systems and how they perform in terms of the efficiency and outcome of root canal preparation.

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.

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.

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.

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.

Hypophosphatemia rickets is a rare disease that is divided into two categories, namely, hereditary and acquirability. Its clinical manifestations include growth disorders, limb deformities and dysfunction, poor mineralization of the teeth, and growth retardation in children as well as hyperparathyroidism, osteoarthritis, osteomalacia, and pseudofracture in adults. Oral manifestations include non-carious teeth with recurrent apical periodontitis, periapical abscess and even cellulitis, periodontitis, and early tooth loss. X-linked hypophosphatemia rickets (XLHR) accounts for approximately 80% of all hypophosphatemia rickets. We report a 3-year-old child with XLHR whose first diagnosis was apical periodontitis of multiple non-carious and non-traumatic teeth. Through medical history, clinical examination, laboratory examination, radiographic findings, genotype testing, and literature analysis, we analyze the pathogenesis, clinical manifestations, radiographic features, diagnosis and differential diagnosis, treatment, and follow-up. This work provides reference for clinical diagnosis and treatment and reduces missed diagnosis and misdiagnosis by dentists.

Objective The effect of metal precrown restoration of distal proximal maxillofacial caries in the first deciduous molar on the composite resin filling of mesio-adjacent maxillofacial caries in the second deciduous molar was investigated. Methods A total of 80 children aged 4-8 who visited our clinic were selected, and 120 teeth were examined. Two consecutive deciduous molars in one jaw were considered a single case when the distal proximal maxillary surface of the first deciduous molar and the mesial proximal maxillary surface of the second deciduous molar simultaneously had caries. The teeth were randomly divided into two groups: group A (68 cases), in which the first and second molars were repaired with composite resin, and group B (52 cases), in which the first deciduous molar was repaired with metal precrown after composite resin filling and the second deciduous molar was filled with composite resin. The two groups were compared in terms of the success rate of composite resin filling in the second deciduous molar. Results At 3 months, no significant difference (P>0.05) was found between groups A (92.65%) and B (96.15%). At 6 months, no significant difference (P>0.05) was observed between groups A (89.71%) and B (94.23%). At 12 months, statistically significant difference (P<0.05) was found between groups A (73.53%) and B (88.46%); At 24 months, statistically significant difference (P<0.05) was found between groups A (66.18%) and B (86.54%). Conclusion Compared with composite resin filling of the first deciduous molar, the metal precrown restoration of the first deciduous molar can improve the success rate of composite resin filling of the second deciduous molar.

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.

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 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.

The clinical demand for occlusal reconstruction increases rapidly with increasing number of patients who have lost their normal occlusion because of tooth wear and dentition defects. Occlusal reconstruction is a special type of restoration defined as a comprehensive restoration of the function of the stomatognathic system by reestablishing a uniform and stable occlusal relationship between the upper and lower dentitions. Occlusal function analysis is an important part of occlusal reconstruction to achieve accurate restoration design and adjustment. Digital occlusal function analysis was conducted to monitor the movement of the mandible and obtain related data for the parameter design of occlusal reconstruction. Preoperative design, intraoperative adjustment, and postoperative verification were achieved, thereby improving the efficiency and accuracy of occlusal reconstruction.

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 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 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 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.

The temporomandibular joint (TMJ) is the critical functional unit in the human stomatognathic system. Damage of the TMJ causes orofacial dysfunction and secondary jaw deformities, leading to seriously decreased quality of life in patients. The TMJ prosthetic replacement is an important treatment method for severe joint destruction because of its remarkable advantages compared with other methods. In recent years, this technique has gradually attracted wide attention in China, but it has not been popularized on a large scale in our country because of several limitations. Thus, in this study, the clinical experience of patients with TMJ prosthetic replacement in clinical units was summarized, and the treatment principles, treatment processes, and technical advantages were systematically discussed, aiming to promote the popularization and application of TMJ prosthetic replacement in China.

Centric relation (CR) was used in the complete dentures for edentulous jaws firstly. Then, CR was gradually applied in the clinical diagnosis and treatment of dentate jaws. Regarding the application of CR in dentate jaws, there are many doubts about its rationality. For instance, should CR be the core of diagnosis and treatment of temporomandibular disorders? Should CR be used as the jaw position of establishing occlusion in occlusal reconstruction? Should CR serve as the target jaw position in orthodontic treatment? Meanwhile, varieties of CR clinical applications are objective. According to the existing evidence, this paper summarizes the applicable conditions of several main clinical situations with little controversy. We preliminarily put forward the decision tree for the clinical application of CR, which can be used as a reference in clinical practice.

Objective This study proposes a chairside digital design and manufacturing method for band and loop space maintainers and preliminarily validates its clinical feasibility. Methods Clinical cases of 10 children requiring space maintenance caused by premature loss of primary teeth were collected. Intraoral scan data of the affected children were also collected to establish digital models of the missing teeth. Using a pediatric band and loop space maintainer design software developed by our research team, a rapid personalized design of band and loop structures was achieved, and a digital model of an integrated band and loop space maintainer was ultimately generated. A chairside space maintainer was manufactured through metal computer numerical control machining for the experimental group, whereas metal 3D printing in the dental laboratory was used for the control group. A model fitting assessment was conducted for the space maintainers of both groups, and senior pediatric dental experts were invited to evaluate the clinical feasibility of the space maintainers with regard to fit and stability using the visual analogue scale scoring system. Statistical analysis was also performed. Results The time spent in designing and manufacturing the 10 space maintainers of the experimental group was all less than 1 h. Statistical analysis of expert ratings showed that the experimental group outperformed the control group with regard to fit and stability. Both types of space maintainers met clinical requirements. Conclusion The chairside digital design and manufacturing method for pediatric band and loop space maintainers proposed in this study can achieve same-day fitting of space maintainers at the first appointment, demonstrating good clinical feasibility and significant potential for clinical application.

Objective To determine the optimal placement of miniscrews, this study compared adult male and female patients in terms of cortical bone density, cortical bone thickness, and available bone width in the infrazygomatic crest region. Methods The cone beam computed tomography imaging data of 200 patients (20-30 years old; 100 males and 100 females) were collected. The right maxillary posterior teeth in the sagittal plane were divided into six levels from proximal to distal, and three measurement sites were positioned at vertical distances of 8, 10, and 12 mm from the cementum. Cortical bone density, cortical bone thickness, and available bone width were measured in 18 measurement sites in the infrazygomatic crest and analyzed statistically. Results The highest cortical bone density, cortical bone thickness, and available bone width in the infrazygomatic crest in adult male and female patients were at the level of the interradicular space between the maxillary second premolar and maxillary first molar. The bone cortical density and thickness increased with vertical height, whereas the available bone width decreased with increasing vertical height. Differences were observed in cortical bone density, cortical bone thickness, and available bone width between adult male and female patients. Conclusion The optimal implantation sites of the micro-implant anchorages in the infrazygomatic crest were at the level of the interradicular space between the maxillary second premolar and the maxillary first molar, and the vertical height of the optimal implantation site in males was appropriately higher than that in females.

Objective This clinical study aimed to assess the trueness of three intraoral scanners for the recor-ding of the maximal intercuspal position (MIP) to provide a reference for clinical practice. Methods Ten participants with good occlusal relationship and healthy temporomandibular joint were recruited. For the control group, facebow transferring procedures were performed, and bite registrations at the MIP were used to transfer maxillary and mandibular casts to a mechanical articulator, which were then scanned with a laboratory scanner to obtain digital cast data. For the experimental groups, three intraoral scanners (Trios 3, Carestream 3600, and Aoralscan 3) were used to obtain digital casts of the participants at the MIP following the scanning workflows endorsed by the corresponding manufacturers. Subsequently, measurement points were marked on the control group’s digital casts at the central incisors, canines, and first molars, and corresponding distances between these points on the maxillary and mandibular casts were measured to calculate the sum of measured distances (D_A). Distances between measurement points in the incisor (D_I), canine (D_C), and first molar (D_M) regions were also calculated. The control group’s maxillary and mandibular digital casts with the added measurement points were aligned with the experimental group’s casts, and D_A, D_I, D_C, and D_M values of the aligned control casts were determined. Statistical analysis was performed on D_A, D_I, D_C, and D_M obtained from both the control and experimental groups to evaluate the trueness of the three intraoral scanners for the recording of MIP. Results In the control group, D_A, D_I, D_C, and D_M values were (39.58±6.40), (13.64±3.58), (14.91±2.85), and (11.03±1.56) mm. The Trios 3 group had values of (38.99±6.60), (13.42±3.66), (14.55±2.87), and (11.03±1.69) mm. The Carestream 3600 group showed values of (38.57±6.36), (13.56±3.68), (14.45±2.85), and (10.55±1.41) mm, while the Aoralscan 3 group had values of (38.16±5.69), (13.03±3.54), (14.23±2.59), and (10.90±1.54) mm. Analysis of variance revealed no statistically significant differences between the experimental and control groups for overall deviation D_A (P=0.96), as well as local deviations D_I (P=0.98), D_C (P=0.96), and D_M (P=0.89). Conclusion With standardized scanning protocols, the three intraoral scanners demonstrated comparable trueness to traditional methods in recording MIP, fulfilling clinical requirements.

Objective This study aimed to explore the expression trends of innate immune cells and immune-checkpoint molecules validated by data calculation in the process of oral mucosal carcinogenesis, as well as to explore methods of suppressing oral mucosal carcinogenesis based on immunotherapy by predicting their interactions. Me-thods　1) The cancer genome atlas (TCGA) database comprehensively scores immune cells and immune-checkpoint molecules in the process of oral mucosal carcinogenesis and screens out intrinsic immune cells and immune-checkpoint molecules that interfere with tumor immune escape. 2) Clinical patient blood routine data were collected for the statistical analysis of peripheral blood immune cells during the progression of oral mucosal carcinogenesis. Immune cells in peripheral blood that may affect the progression of oral mucosal carcinogenesis were screened. 3) Immunohistochemical staining was performed on intrinsic immune cells and immune-checkpoint molecules validated based on data calculation in various stages of oral mucosal carcinogenesis. 4) Special staining was used to identify innate immune cells in various stages of oral mucosal carcinogenesis based on data-calculation verification. 5) Survival analysis was conducted on intrinsic immune cells and immune-checkpoint molecules validated based on data calculation during the process of oral mucosal carcinogenesis. The association of intrinsic immune cells and immune-checkpoint molecules with the prognosis of oral squamous cell carcinoma was verified. Results The expression of monocytes and neutrophils increased during the process of oral mucosal carcinogenesis. The expression of eosinophils showed a single peak trend of up and down. The expression of mast cells decreased. In the process of oral mucosal carcinogenesis, the expression of the immune-checkpoint molecules cytotoxic T-lymphocyte-associated protein 4 (CTLA4) and programmed cell death-ligand (PD-L1) increased. The expression trends of monocytes, neutrophils, and eosinophils were positively correlated with those of CTLA4 and PD-L1 immune-checkpoint molecules. The expression trend of mast cells was negatively correlated with the expression of CTLA4 and PD-L1. Monocytes, neutrophils, and eosinophils may promote tumor immune escape mediated by CTLA4 and/or PD-L1, thereby accelerating the progression of oral mucosal carcinogenesis. Mast cells may inhibit tumor immune escape mediated by CTLA4 and/or PD-L1, delaying the progression of oral mucosal carcinogenesis. Conclusion Therefore, interference with specific immune cells in innate immunity can regulate the expression of CTLA4 and/or PD-L1 to a certain extent, inhibit tumor immune escape, and delay the progression of oral mucosal carcinogenesis.

Objective This study aimed to investigate the temporal and spatial changes in the expression of periostin during periodontal inflammation in mice. Methods A periodontitis model was constructed using silk thread ligation. Mice were randomly divided into five groups including control group, 4-day ligation group, 7-day ligation group, 14-day ligation group, and self-healing group (thread removal for 14 days after 14-day ligation). Micro-CT and histological staining were performed to characterize the dynamic changes in the mouse periodontal tissue in each group. RNAscope and immunohistochemical staining were used to analyze the pattern of changes in periostin at various stages of periodontitis. The cell experiment was divided into three groups: control group, lipopolysaccharide (LPS) stimulation group (treated with LPS for 12 h), and LPS stimulation removal group (treated with LPS for 3 h followed by incubation with medium for 9 h). Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of periostin, transforming growth factor-β1 (TGF-β1), and matrix metalloproteinase 2 (MMP2). Results Significant alveolar bone resorption was observed 7 days after ligation. With increasing duration of ligation, the damage to the mouse periodontal tissue was aggravated, which manifested as increased osteoclasts, widening of the periodontal membrane space, and decreased alveolar bone height. Some degree of periodontal tissue repair was observed in the self-healing group. Periostin expression decreased at 4 and 7 days compared with the control group and increased at 14 days compared with 4 and 7 days. A significant recovery was found in the self-healing group. The qRT-PCR results showed that the expression of periostin and TGF-β1 in the LPS stimulation group decreased compared with that in the control group but significantly recovered in the LPS removal group. Conclusion Periostin expression in the PDL of mice showed a downward and upward trend with inflammation progression. The significant recovery of periostin expression after removing inflammatory stimuli may be related to TGF-β1, which is crucial to maintain the integrity of the PDL.

Objective To investigate the mechanism of circadian clock protein Bmal1 (Bmal1) on renal injury with chronic periodontitis, we established an experimental rat periodontitis model. Methods Twelve male Wistar rats were randomly divided into control and periodontitis groups (n=6, each group). The first maxillary molars on both sides of the upper jaw of rats with periodontitis were ligated by using orthodontic ligature wires, whereas the control group received no intervention measures. After 8 weeks, clinical periodontal parameters, including probing depth, bleeding index, and tooth mobility, were evaluated in both groups. Micro-CT scanning and three-dimensional image reconstruction were performed on the maxillary bones of the rats for the assessment of alveolar bone resorption. Histopatholo-gical observations of periodontal and renal tissues were conducted using hematoxylin-eosin (HE) and periodic acid-Schiff (PAS) staining. Renal function indicators, such as creatinine, albumin, and blood urea nitrogen levels, and oxidative stress markers, including superoxide dismutase, glutathione, and malondialdehyde levels, were measured using biochemical assay kits. MitoSOX red staining was used to detect reactive oxygen species (ROS) content in the kidneys. The gene and protein expression levels of Bmal1, nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) in rat renal tissues were assessed using real-time quantitative polymerase chain reaction (RT-qPCR) and immunohistochemical staining. Results Micro-CT and HE staining results showed significant bone resorption and attachment loss in the maxillary first molar region of the periodontitis group. Histological examination through HE and PAS staining revealed substantial histopathological damage to the renal tissues of the rats in the periodontitis group. The findings of the assessment of renal function and oxidative stress markers indicated that the periodontitis group exhibited abnormal levels of oxidative stress, whereas the renal function levels showed abnormalities without statistical significance. MitoSOX Red staining results showed that the content of ROS in the renal tissue of the periodontitis group was significantly higher than that of the control group, and RT-qPCR and immunohistochemistry results showed that the expression levels of Bmal1, Nrf2, and HO-1 in the renal tissues of the rats in the periodontitis group showed a decreasing trend. Conclusion Circadian clock protein Bmal1 plays an important role in the oxidative damage process involved in the renal of rats with periodontitis.

Objective This study aimed to systematically compare the effects of flapless and flapped implantations on the surrounding soft tissues of dental implants. Methods Nine databases were searched, including PubMed, Embase, Cochrane Library, Web of Science, Clinical Trials, OpenGrey, OpenDoar, Scopus, and Ovid, from January 1, 2013, to August 27, 2023. Randomized controlled trials comparing flapless implantation with flapped implantation for restoration of missing teeth were included. Meta-analysis was conducted on studies that met the inclusion criteria by using RevMan 5.3 and Stata 14.0. Results A total of 1 245 articles were retrieved, and 17 studies were ultimately included. The results of Meta-analysis showed that flapless implantation resulted in better healing of the soft tissues around the dental implants than flapped implantation. Moreover, flapless implantation showed superior changes in implant success rate [mean difference (MD)=1.06, 95% confidence interval (CI) (1.02, 1.10), P=0.004], the width of keratinized gingival changes [MD=0.10, 95%CI (0.00, 0.20), P=0.04], and probing depth [MD=-0.60, 95%CI (-0.67, -0.53), P<0.000 01], with statistically significant differences. The final combined results of modified plaque index [standardized mean difference (SMD)=-0.41, 95%CI (-0.81, 0.00), P=0.05] and modified sulcus bleeding index [SMD=-0.44, 95%CI (-0.78, -0.10), P=0.01] showed superiority over flapped implantation. The papillary presence index was higher in the flapless implantation group than in the flapped implantation group. No statistically significant differences were observed in plaque index and gingival indices changes between the two groups. Conclusion Flapless implantation can achieve higher implant success rate, smaller changes in the width of keratinized gingival, and smaller probing depths than flapped implantation. It also has advantages in terms of modified plaque index, modified sulcus bleeding index, and papillary presence index.

Objective To explore the mechanism of ginseng in the treatment of periodontitis based on network pharmacology and molecular docking technology. Methods Potential targets of ginseng and periodontitis were obtained through various databases. The intersection targets of ginseng and periodontitis were obtained by using VENNY, the protein-protein interaction network relationship diagram was formed on the STRING platform, the core target diagram was formed by Cytoscape software, and the ginseng-active ingredient-target network diagram was constructed. The selected targets were screened for gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis. The core targets of ginseng’s active ingredients in treating periodontitis were analyzed by molecular docking technique. Results The 22 ginseng’s active ingredients, 591 potential targets of ginseng’s active ingredients, 2 249 periodontitis gene targets, and 145 ginseng-periodontitis intersection targets were analyzed. Ginseng had strong binding activity on core targets such as vascular endothelial growth factor A and epidermal growth factor receptor, as well as hypoxia induced-factor 1 (HIF-1) signaling pathway and phosphatidylinositol 3-kinase-protein kinase B (PI3K-Akt) signaling pathway. Conclusion Ginseng and its active components can regulate several signaling pathways such as HIF-1 and PI3K-Akt, thereby indicating that ginseng may play a role in treating periodontitis through multiple pathways.

Objective This study aimed to reveal critical genes regulating peri-implantitis during its development and construct a diagnostic model by using random forest (RF) and artificial neural network (ANN). Methods GSE-33774, GSE106090, and GSE57631 datasets were obtained from the GEO database. The GSE33774 and GSE106090 datasets were analyzed for differential expression and functional enrichment. The protein-protein interaction networks (PPI) and RF screened vital genes. A diagnostic model for peri-implantitis was established using ANN and validated on the GSE33774 and GSE57631 datasets. A transcription factor-gene interaction network and a transcription factor-micro-RNA (miRNA) regulatory network were also established. Results A total of 124 differentially expressed genes (DEGs) involved in the regulation of peri-implantitis were screened. Enrichment analysis showed that DEGs were mainly associated with immune receptor activity and cytokine receptor activity and were mainly involved in processes such as leukocyte and neutrophil migration. The PPI and RF screened six essential genes, namely, CD38, CYBB, FCGR2A, SELL, TLR4, and CXCL8. The receiver operating characteristic curve (ROC) indicated that the ANN model had an excellent diagnostic performance. FOXC1, GATA2, and NF-κB1 may be essential transcription factors in peri-implantitis, and hsa-miR-204 may be a key miRNA. Conclusion The diagnostic model of peri-implantitis constructed by RF and ANN has high confidence, and CD38, CYBB, FCGR2A, SELL, TLR4, and CXCL8 are potential diagnostic markers. FOXC1, GATA2, and NF-κB1 may be essential transcription factors in peri-implantitis, and hsa-miR-204 plays a vital role as a critical miRNA.

Objective This study aims to investigate the primary target and potential mechanism of mangiferin (MF) in treating oral submucous fibrosis (OSF) through Gene Expression Omnibus (GEO) database chip mining, network pharmacology, and molecular docking techniques. Methods Potential therapeutic targets for OSF were identified using GEO chip data. The potential targets of MF were predicted, and disease-related targets for OSF were collected from databases. A Venn diagram was created using the EVenn platform to identify overlapping targets. The protein-protein interaction (PPI) network was constructed using the STRING database. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed using the DAVID platform. Cytoscape 3.10.1 software was used to visualize a drug-target-pathway-disease network, while AutoDocktools 1.5.6 software was employed for molecular docking analysis. Results A total of 356 potential targets for MF and 360 disease-related targets for OSF were obtained from multiple databases. The top 15 key target proteins in the PPI network were selected as significant candidates. GO function and KEGG pathway enrichment analyses revealed that MF treatment primarily involved advanced glycation end products-receptor (AGE-RAGE), epidermal growth factor receptor (EGFR), and other signaling pathways associated with OSF pathogenesis. Molecular docking analysis demonstrated that MF exhibited a strong binding activity toward AKT serine kinase 1 (AKT1), tumor necrosis factor (TNF), and other core targets. Conclusion These findings suggest that MF may exert its therapeutic effects on OSF through a multitarget approach involving various signaling pathways.

This study explores the potential application of computer aided design (CAD)/computer aided manufac-turing (CAM) for one-piece glass fiber posts and cores in restoring tooth defects post-removal of a broken fiber post using a digital guide plate. This paper reports a fractured left upper incisor fiber post removed using a customized needle and digital guide plate. Following root canal retreatment, CAD/CAM integrated fiber post-core and zirconia full crown restoration were completed. The occlusion testing was conducted using the T-Scan Ⅲ system. This study offers insights for managing secondary repair after fiber post fractures.

Oral wounds caused by injuries, surgeries, diseases, and chemical irritations bring pain to the patient and increase the risk of infection. Effective wound protection and repair are crucial for improving patients’ quality of life and maintaining oral health. Wound dressings provide ideal healing conditions by isolating the wound from the oral environment. However, in the highly moist, microbiologically rich environment of the oral cavity, maintaining the stability of wound dressings remains a considerable challenge. Hydrogels show promising prospects for oral applications and are gradually becoming a research hotspot for addressing the challenges of oral wound protection and repair due to their excellent biocompatibility and versatile performance. In this paper, the current design strategies of hydrogel wound dressings that overcome the unique oral environment, achieve sustained adhesion and fulfill their functions are reviewed to provide new insights for the design of ideal oral wound barrier materials.

Objective This study aimed to investigate the incidence and severity of surgical fear in patients with oral and maxillofacial tumors. Methods The survey participants were composed of patients with oral and maxillofacial tumors, who were scheduled to undergo surgery. A general information questionnaire, the Surgical Fear Questionnaire (SFQ), the Patient Health Questionnaire (PHQ)-9, and the Generalized Anxiety Disorder (GAD)-7 score were used for the investigation. Results A total of 203 patients were investigated. Among them, 85.22% had fear of surgery. The median score of SFQ was 20, and the quartile was (6, 36). The patients were categorized into none, mild, moderate, and severe groups according fear level. Gender, diabetes, obvious discomfort before surgery, PHQ-9, and GAD-7 scores were the variables with statistical difference in each fear level. Multifactor analysis showed that women were more likely to have moderate and severe fear than men (OR=2.19, P=0.03; OR=2.72, P=0.01), patients with obvious preoperative discomfort symptoms were more inclined to have no fear (OR=4.73, P=0.02), and patients with diabetes were more likely to have severe fear (OR=3.33, P=0.02). The incidence rates of depression and anxiety were 31.03% and 24.63%, respectively. The incidence of anxiety and depression in patients with severe fear was 40.00%. Surgical fear was moderately positively correlated with anxiety (r=0.491, P<0.001) and depression (r=0.514, P<0.001). Conclusion The fear of surgery in patients with oral and maxillofacial tumors is common and distributed in all levels. Medical staff can screen and assess patients with moderate and severe fear of surgery in accordance with the influencing factors and implement targeted interventions to reduce fear of surgery, anxiety, and depression on the basis of the source of fear.

Objective This study aimed to evaluate the application of digital impression and resin model technology in removable partial dentures (RPD) for Kennedy classⅠandⅡdentition defects. Methods Patients with Kennedy classⅠorⅡdental defect were selected and grouped in accordance with the following denture production processes: digital impression/resin model/cast cobalt-chromium alloy framework group (group A), digital impression/resin model/laser printed titanium framework group (group B), alginate impression/plaster model/cast cobalt-chromium alloy framework group (group C), and alginate impression/plaster model/laser printed titanium framework group (group D), with 40 cases in each group. The final RPD was examined in place in the mouth, and the evaluation indicators included the retention force of clamp ring, the tightness of connector and base, and the accuracy of occlusion. The evaluation scores of each index were used for analysis on the Kruskal-Wallis rank-sum test. Results No statistically significant difference in the score of each index was found among the four groups in RPD. Conclusion The cast cobalt-chromium alloy and laser-printed titanium framework RPD using digital impression and resin model can meet the clinical restoration requirements of patients with Kennedy classⅠandⅡdentition defects.

Dental invagination is an abnormality of the crown or root development induced during tooth germ development when the enamel-forming apparatus or epithelial root sheath overpopulates and folds into the papilla. In severe cases, the invaginated channels are connected to the pulp and periodontal tissues, often causing endodontic and periapical diseases. The complex anatomical pattern of this disease adds difficulty in its preoperative diagnosis and clinical operation. In this paper, we report a case of non-surgical treatment assisted by cone beam CT and microscopy for maxillary lateral incisor double dens invaginatus type Ⅲ (Ⅲa and Ⅲb) with apical periapical infection. After 1-year follow-up, the affected tooth was asymptomatic and the periapical lesion was significantly reduced.

Objective This study aims to evaluate the efficacy of concentrated growth factor (CGF) membrane and collagen as barrier materials in sealing the alveolar socket in alveolar ridge preservation (ARP) in the posterior region during a one-year follow-up. Methods A total of 24 patients who underwent ARP in the posterior region were selected for inclusion and randomly assigned to the CGF group (12 cases) and Collagen group (12 cases). The patients in both groups underwent extraction of posterior teeth. The extraction sockets were filled with a bone substitute to the level of the pre-extraction buccal and lingual or palatal alveolar bone plates. The wounds in the CGF group were closed with a fabricated CGF overlaying the upper edge of the bone substitute material, whereas those in the Collagen group were closed with Bio-Oss Collagen. The implants were placed after 6 months. The evaluation was based on implant retention, re-grafting rate, and vertical and horizontal alveolar ridge bone volume changes measured by cone beam computed tomography (CBCT). Data were statistically analyzed using SPSS 28.0 software. Results No patient withdrew throughout the follow-up period. No implant failure and no severe peri-implant or mucosal soft tissue complications were observed. Six months after the operation, the degree of vertical alveolar ridge height resorption in the CGF group was lower than that in the Collagen group (P<0.05). There were no statistically difference between the groups at 1 year after the operation (P>0.05). The amount of bone reduction in horizontal alveolar ridge width showed no difference between the groups at 6 months and 1 year after surgery (P>0.05). Conclusion CGF membrane and Bio-Oss Collagen as barrier materials for posterior ARP inhibited reduction in alveolar ridge bone mass.

In clinical dentistry, addressing unique conditions such as tilted, elongated, and torsion teeth during preparation can be effectively managed through digital tooth morphology design. The production of a multi-stage 3D-printed guide offered a more efficient and accurate solution. This article presented a case of significant inclination, elongation, and torsion in the maxillary and mandibular canines that were successfully treated using crown restoration modification. A crown preparation guide was fabricated based on the final form design of the restoration using the target restorative space analysis technique to ensure precise tooth preparation. A tooth preparation guide was also designed and utilized further to enhance accuracy and efficiency during complex tooth preparation. The combined application of these multi-stage guides demonstrated promising clinical prospects.

Most of the maxillary impacted third molars are located in the maxillary tuberosity, where the vision and operation space are limited. This paper reports a case of surgical extraction of the left maxillary horizontal superhigh impacted third molar, which is located between the roots of the adjacent teeth and is closely related to the maxillary sinus. The digital simulation technology was used to reconstruct a three-dimensional visual image of the patient’s maxilla, related teeth, and other adjacent anatomical structures to assist in finding the optimal surgical method accurately. Root dislocation before the crown not only protects the roots of the adjacent tooth, but also reduces the risk of maxillary sinus lining damage or perforation during operative procedures, improves the efficiency of the operation, and reduces surgical trauma, which conforms to the concept of minimally invasive surgery and provides a new idea and experience for the clinical extraction of such maxillary impacted third molars.