In the field of oral medicine, 3D-printed individualized titanium mesh technology is gradually becoming an important means for the treatment of severe alveolar bone defect augmentation. This article provides a comprehensive analysis of the advantages of this technology, the evaluation of osteogenic effects, and the progress of research in clinical applications. In response to the current issue of variability in bone augmentation outcomes, this paper delves into multiple factors affecting bone augmentation effects, including individualized titanium mesh design (involving the thickness, pore size, pore shape, porosity, contour shape, selection of titanium alloy materials, and 3D printing technology), intraoperative procedures (the accuracy of placement during 3D-printed individualized titanium mesh surgery), and postoperative care (including the prevention of complications, formation of pseudoperiosteum, and stability of the titanium mesh). By integrating the clinical experience and research findings of our team, we propose a series of targeted optimization strategies, including designing, manufacturing, and clinically applying self-positioning individualized titanium meshs (positioning wings + individualized titanium meshs) to improve the positioning accuracy of the titanium mesh; propose individualized treatment processes and titanium mesh design schemes based on specific conditions of alveolar bone defects and soft tissue status; and emphasize the importance of long-term stable fixation of the titanium mesh to reduce the risk of postoperative mesh loosening and displacement. In addition, we appropriately summarize the evaluation methods for the bone augmentation effects of 3D-printed individualized titanium meshes, covering the following key indicators: (1) vertical bone augmentation and horizontal bone augmentation; (2) changes in bone contour morphology; (3) bone volume increase; (4) clinical indicators (surgical success rate, titanium mesh exposure, infection rate, and postoperative recovery); (5) aesthetic effect evaluation; (6) long-term stability; (7) radiological assessment; (8) patient satisfaction; and (9) precision of surgical operation, aiming to assist doctors in comprehensively assessing and in-depth analyzing the surgical outcomes to achieve the best therapeutic effects. The purpose of this article is to provide a reference for the optimization and clinical application of 3D-printed individualized titanium mesh technology and to lay a theoretical foundation for achieving the best osteogenic effects.

Objective To reveal the role of periodontal ligament stem cell-derived exosomes (PDLSC-Exos) in orthodontic bone remodeling, in order to provide new therapeutic strategies for orthodontic tooth movement (OTM). Methods This study has been reviewed and approved by the Ethics Committee. Healthy periodontal ligament tissues from clinical orthodontic reduction extractions were collected, and periodontal ligament stem cells (PDLSCs) were isolated and cultured. When cultured to the third generation, their self-renewal ability and multidirectional differentiation potential were detected. PDLSC-Exos were isolated and purified by gradient centrifugation and identified by transmission electron microscopy, immunofluorescence, ZetaView, and nanoflow cytometry. The co-culture of 10 μg/mL PDLSC-Exos and PDLSCs (PDLSCs+Exos) induced osteogenic differentiation to evaluate the effect of osteogenesis. Bone marrow-mononuclear cells (BMMs), promoted by osteoclast differentiation [30 ng/mL macrophage colony stimulating factor (M-CSF) + 50 ng/mL receptor activator of nuclear factor-κ B ligand (RANKL)], and then were treated with 10 μg/mL PDLSC-Exos to assess the effect on osteoclasts. We established a rat model of OTM, and 50 μg/mL PDLSC-Exos was injected locally into the periodontal ligament before we established the model (OTM + Exos), every 2 days for 14 days. Alveolar bone remodeling was analyzed by micro-CT, and alveolar bone osteoclasts were analyzed by immunohistochemistry and immunofluorescence. Results The isolated and purified PDLSCs met the basic characteristics of mesenchymal stem cells, and PDLSC-Exos had typical characteristics of extracellular vesicles. PDLSCs-Exos significantly promoted the osteogenic differentiation of PDLSCs, and promoted the osteoclast differentiation and bone resorption activity of BMMs (P < 0.05). The rate of alveolar bone remodeling in rats with local periodontal injection of PDLSC-Exos was significantly accelerated, and the tooth movement distance was significantly increased (P < 0.05); immunohistochemistry results showed that PDLSC-Exos promoted the differentiation of osteoclasts (P < 0.05). In addition, immunofluorescence showed that PDLSC-Exos co-localized with osteoclasts, indicating that PDLSC-Exos may promote osteoclast differentiation in vivo. Conclusion PDLSC-Exos accelerate the rate of orthodontic bone remodeling by promoting osteogenic differentiation of PDLSCs and osteoclast differentiation of BMMs, thereby accelerating OTM.

Objective To investigate the effect of neurite outgrowth inhibitor extracellular peptide residues 1-40 (NEP1-40) combined with poly (lactic-co-glycolic acid) (PLGA) and gelatin electrospun fiber membrane on facial nerve repair in rats. Methods According to the principle of random grouping, 108 male SD rats were divided into four groups (n = 27 in each group, approved by the ethics committee), namely, the sham group, control group, PLGA group, and NEP1-40 + PLGA group. A facial nerve fracture model was established for all of the groups except for the sham group. The control group received no further treatment, the PLGA group and the NEP1-40+PLGA group were supported by PLGA membrane, and the NEP1-40+PLGA group received one immediate local injection of NEP1-40 (5 μg/μL) at a dose of 10 μL. Facial nerve function analysis, electrophysiological examination, transmission electron microscope observation, HE staining, and immunohistochemical staining of myelin marker S100β and axonal marker β3-tubulin were used to evaluate the recovery of injured facial nerves of rats at 2, 4 and 8 weeks. Results At 8 weeks, the facial nerve function score of the NEP1-40+PLGA group was better than that of the control group and PLGA group (P < 0.001), and facial nerve function was significantly restored. Electrophysiological examination of nerve action potentials at the injured facial nerve showed that the amplitude in the NEP1-40+PLGA group was higher than that of the control group and PLGA group (P < 0.001), but there was no significant difference in latency and conduction velocity results between the groups (P > 0.05). At 2, 4, and 8 weeks, transmission electron microscopy showed that the number of myelinated nerve fibers and myelin sheath thickness in the cross-section of the injured facial nerve in the NEP1-40+PLGA group were greater than those in the other groups (P < 0.05). At 8 weeks, HE staining showed that the facial nerves in the control group had partially recovered, but the overall cell distribution was uneven and the boundary with surrounding tissues was slightly blurred. In contrast, the NEP1-40+PLGA group had a relatively uniform cell distribution and a clearer boundary with surrounding tissues. At 2, 4, and 8 weeks, the immunohistochemical results showed that in the cross-section of the injuried facial nerve, NEP1-40 increased the expression of neural markers S100 β and β3-tubulin, especially β3-tubulin, which was close to normal levels (P > 0.05). Conclusion NEP1-40 is beneficial for the generation of new myelin sheaths and axons at the site of injury, and it can promote the repair and regeneration of injured facial nerves to a certain extent, thus accelerating the recovery of injured nerve function.

Objective To investigate the biomechanical effect of alveolar bone graft (ABG) resorption on the maxillary alveolar process under occlusal force in a patient with unilateral cleft lip and palate (UCLP) and provide evidence for the clinical application of ABG. Methods A 3D finite element maxillary model of an 11-year-old female patient with UCLP was generated. The occlusal force was applied to six models with different ABG resorption, namely non-resorption, upper 1/3 resorption, upper 2/3 resorption, lower 1/3 resorption, lower 2/3 resorption, and upper&lower 1/3 resorption. The properties of structures in all models were set to be linear, elastic, and isotropic. The displacement and Von Mises stress of each reference node of the alveolar process were compared and analyzed. Results Under occlusal force, the most significant displacement of the alveolar process was located in the anterior area, and it decreased gradually from anterior area to both sides in all groups. The displacement values of the alveolar process under cleft side lateral occlusion were as follows: non-resorption group < lower 2/3 resorption group < upper&lower 1/3 resorption group < lower 1/3 resorption group < upper 2/3 resorption group < upper 1/3 resorption group. The displacement values of the alveolar process under centric occlusion were as follows: non-resorption group < lower 1/3 resorption group < upper&lower 1/3 resorption group < upper 2/3 resorption group < lower 2/3 resorption group < upper 1/3 resorption group. The displacement values of the alveolar process under non-cleft side lateral occlusion were as follows: non-resorption group < lower 1/3 resorption group < upper 1/3 resorption group < lower 2/3 resorption group < upper&lower 1/3 resorption group < upper 2/3 resorption group. The stress was concentrated on the premolar area on the functional side of the alveolar process, followed by the canine and molar areas in all groups. The stress values of the alveolar process under cleft side lateral occlusion were as follows: non-resorption group < lower 2/3 resorption group < upper&lower 1/3 resorption group < upper 2/3 resorption group < lower 1/3 resorption group < upper 1/3 resorption group. The stress values of the alveolar process under centric occlusion were as follows: non-resorption group < upper 1/3 resorption group < lower 1/3 resorption group < lower 2/3 resorption group < upper&lower 1/3 resorption group < upper 2/3 resorption group. The stress values of the alveolar process under non-cleft side lateral occlusion were as follows: non-resorption group < lower 2/3 resorption group < upper&lower 1/3 resorption group < lower 1/3 resorption group < upper 2/3 resorption group < upper 1/3 resorption group. Under occlusal force, the displacement and stress of the alveolar process in the non-resorption model were significantly lower than those in other models. The displacement and stress of the alveolar process in the models with resorption in the lower area of the ABG were significantly lower than those in the models with resorption in the upper-middle areas of the ABG. Conclusion After unilateral complete cleft lip and palate bone grafting, the integrity and continuity of the middle and upper parts of the alveolar process bone grafting play a key role in the biomechanical status of the alveolar process. If bone resorption occurs in the above parts, bone grafting should be considered.

Objective To explore the therapeutic effects of different surgical methods for temporomandibular joint disc reduction and anchoring surgery, providing reference for optimizing this surgical procedure. Method The study was approved by the hospital ethics committee. 173 patients (195 joints) who underwent temporomandibular joint disc repositioning and anchoring surgery were selected for retrospective analysis. Patients were categorized into groups A (traditional preauricular incision-scalpel/tissue scissors anterior attachment release), 35 patients (40 joints), B (traditional preauricular incision-plasma bipolar radiofrequency electrode anterior attachment release), 42 patients (46 joints), C (revised tragus incision - scalpel/tissue scissors anterior attachment release), 50 patients (58 joints), and D (revised tragus incision-plasma bipolar radiofrequency electrode anterior attachment release), 46 patients (51 joints). After a 6-month postoperative follow-up, the differences in maximum mouth opening (MMO), visual analogue scale (VAS), effective rate of joint disc reduction, incidence of preauricular numbness, obvious scars among patients in each group at 1, 3, and 6 months were compared postoperatively. Results After surgery, the MMO of all four groups of patients initially shrunk and then gradually increased compared to before surgery. At the 1-month follow-up after surgery, the plasma bipolar radiofrequency release (B+D) group had a smaller impact on the patient’s MMO compared to the surgical knife/tissue scissors release (A+C) group (P < 0.05). Postoperative VAS scores for all four groups showed a gradual decrease from pre-operative levels, with the (B+D) group scoring significantly lower in the first month post-surgery compared to the (A+C) group (P < 0.05). Six months post-surgery, the rate of joint disc reduction of the four groups were higher than 95%, with no significant differences observed between the groups (P > 0.05). Patients in the revised tragus incision (C+D) group experienced a lower rate of preauricular numbness compared to those in the traditional preauricular incision (A+B) group (4.59% vs. 12.79%, P < 0.05), The incidence of obvious scars in the (C+D) group was significantly lower than that in the (A+B) group (3.67% vs. 23.26%, P < 0.05). Conclusion The revised tragus incision is superior to traditional preauricular incision in terms of protecting the auriculotemporal nerve and the scars were more inconspicuous. Further, the plasma bipolar radiofrequency electrode is superior to the scalpel/tissue scissors in terms of mouth opening recovery and pain control. For temporomandibular joint disc reduction and anchoring surgery, a modified tragus incision combined with plasma bipolar radiofrequency electrode to release the anterior attachment of the joint disc can be recommended as a surgical option.

Objective To explore the advantages of static navigation in locating calcified root canal therapy, and to provide reference for clinical diagnosis and treatment of calcified teeth. Methods A case of acute periapical periodontitis of anterior teeth with full-length calcification of root canal was reported. A lingual minimally invasive approach was used as a conservative method of controlling the infection of teeth and preserving the incisors through the digital guide plate. The diagnosis and treatment of this type of case were analyzed retrospectively with reference to the literature. Results One patient complained that the pain of left anterior teeth was aggravated for 2 days. After examination, he was diagnosed with acute periapical periodontitis of 21 teeth with total root canal calcification. With the assistance of static navigation, the root canal was located after 10 minutes, the calcification was dredged for 15 minutes, and the acute pain symptoms of the patient were relieved that day. After one year of follow-up, there was no discomfort in the teeth, and the range of low-density shadow in the apical film was reduced. After 3 years of follow-up, there was no discomfort in the teeth, and the low-density shadow of the apical root was further reduced by apical film examination. As shown by the results of the literature review, static navigation technology is advantageous because the success rate of dredging calcified root canals is neither associated with the operator’s treatment experience nor the use of microscope and ultrasonic equipment. Regardless of the degree of calcification, this method can significantly reduce the iatrogenic risk, but it is closely related to the accuracy and stability of the guide plate. However, this method is not suitable for calcified teeth with calcification under root canal curvature and limited operating space. Cone-beam computed tomography (CBCT) is recommended to locate calcified root canals, and the imaging quality is an important factor that affects the correct preoperative planning. When performing static navigation endodontic treatment, thermal damage can be reduced by selecting a drill with a small diameter that matches the guide ring and cooling the drill with frozen irrigation solution. Conclusion Static navigation-assisted treatment of calcified root canals is accurate and minimally invasive, which reduces clinical treatment time, preserves the lingual approach at the incisal ridge to further ensure the integrity of teeth, and ensures the long-term preservation of affected teeth.

Objective To evaluate the effectiveness of the biologically oriented preparation technique (BOPT) in restoring traumatic tooth defects within the aesthetic zone, serving as a clinical reference. Methods This study has been reviewed and approved by the Ethics Committee, and informed consent has been obtained from patients. Two cases are detailed, involving traumatic tooth defects under the gingival level, repaired using BOPT in the aesthetic region. Both individuals reported defects resulting from trauma to the upper right anterior teeth occurring over a month prior. Case 1: male, 67 years old. The patient complained of a defect and exposed pulp in the right upper front tooth caused by trauma one month ago. Root canal treatment was performed in the dental pulp department, but there was no discomfort after the surgery. Due to the impact on chewing and aesthetics, restoration is required. Oral examination: 11 residual roots, the deepest part of the lip side fracture, in a V-shape, located 2 mm subgingival, 1-2 mm subgingival near and far, and 2-3 mm supragingival on the palatal side fracture. There is little remaining dental tissue, and filling material can be seen at the root canal opening. The proximal and distal diameters are small, and the tooth root is tilted towards the palatal side. After tapping (-), no obvious looseness is observed. 11 missing gingival papilla near and far; 21 dental crowns tilted towards the middle; thick gingival biotype; dental calculus (+), probing depth (PD): 2-4 mm; Attachment loss (AL): 1-2 mm; Gingival recession (GR): 0-1 mm; bleeding index (BI): 1-2, diagnosis: 11 residual roots; chronic periodontitis. Case 2, male, 34 years old. The patient complained of a defect and exposed pulp in the right upper front tooth caused by trauma one month ago. Root canal treatment was performed in the dental pulp department, but there was no discomfort after the surgery. Due to the impact on chewing and aesthetics, restoration is required. Oral examination: Large area defects were found in sections 12 and 13, with the lip side wall defect reaching about 1 mm subgingival and filling visible at the fracture end. The proximal and distal fracture ends were located about 2-4 mm above the gingiva, and the palatal fracture end was located about 3-4 mm above the gingiva. After tapping (-), no obvious looseness was observed, and the lip side gingiva was slightly red and swollen; thick gingival biotype; dental calculus (++~+++); PD: 3-5 mm; AL: 1-3 mm; GR: 0-2 mm; BI: 2-3; diagnosis: 12 and 13 tooth defects; chronic periodontitis. Treatment plan: following systematic periodontal treatment, the BOPT was implemented using vertical tooth preparation. Temporary restorations were employed to sculpt the soft tissue, and high-translucency zirconia all-ceramic crowns were selected. Utilizing computer aided design/computer aided manufacturing technology, the temporary restorations’ contours were meticulously recreated to achieve optimal pink and white aesthetics. Results The BOPT enables the restoration of traumatic tooth defects in the aesthetic area as well as soft tissue shaping. In Case 1, the patient’s originally palatally inclined the upper right central incisor achieved gingival shaping and harmonized with the upper left central incisor. In Case 2, the previously swollen and poorly shaped gingival margins of the upper right lateral incisor and upper right canine showed significant improvement.By applying the BOPT, the two cases developed healthy soft tissue cuffs, achieving excellent pink and white aesthetic restoration effects. One-year postoperative follow-up of two patients showed that the gingival margins of the upper right central incisor in Case 1 and the upper right lateral incisor and upper right canine in Case 2 were stabilized, with good maintenance of pink and white aesthetic effects. The review of the literatures showed that compared to horizontal tooth preparation, the BOPT combined with a complete digital workflow can be more minimally invasive, using temporary restorations to rebuild the enamel-osteoskeletal contours of the abutment teeth, reshape the soft tissue contours, increase the thickness of the soft tissue, and stabilize the gingival margins. However, the long-term restorative effects still require clinical follow-up observation. Conclusion The BOPT is an effective restorative solution for traumatic teeth in the aesthetic area, as it can be used appropriately in the aesthetic area to obtain good aesthetic restorative effects.

Oral lichen planus (OLP) is a chronic inflammatory disease occurring in the oral mucosa. Clinically, OLP presents with various lesion morphologies, attributed to differences in host immune responses. T-helper 17 cells (Th17) are a crucial component of the cellular immune response, primarily functioning through the secretion of interleukin 17 (IL-17). IL-17 plays a dual role in the oral mucosa: on one hand, it exerts a protective effect by promoting the recruitment of neutrophils driven by chemokines, enhancing the secretion of antimicrobial peptides, and strengthening the mucosal barrier; on the other hand, it binds to target cells in the mucosal tissue, activating downstream inflammatory signaling pathways such as nuclear factor kappa-B(NF-κB) and mitogen-activated protein kinase(MAPK), thereby initiating a pro-inflammatory cascade. This process increases the secretion of pro-inflammatory factors and promotes the recruitment and activation of immune cells, exacerbating inflammation. Current research extensively explores the correlation between the Th17/IL-17 axis and the pathogenesis and progression of OLP. This paper aims to review these developments to provide a research foundation for further elucidating the immunological mechanisms of OLP. Literature review results indicate that upregulation of Th17 and IL-17 in local lesion tissues and peripheral blood of OLP patients may be a key molecular event in the development of OLP. Compared to non-erosive OLP, higher expression levels of Th17 and IL-17 in the tissues and blood of patients with erosive OLP suggest a positive correlation between Th17/IL-17 and disease severity. Clinical studies demonstrate that targeted drugs against the Th17/IL-17 axis, by directly blocking IL-17 or inhibiting the production of Th17 cells, can effectively improve mucosal damage in OLP patients, showcasing potential as a new target for immune therapy. However, whether Th17 and IL-17 influence the pathogenesis of OLP by regulating the oral microbiome remains unclear. In summary, the Th17/IL-17 axis holds potential value as a new target for the immune therapy of OLP, warranting further in-depth research into its biological functions and signaling mechanisms within the inflammatory process of OLP.

Oral squamous cell carcinoma (OSCC), the most common type of head and neck malignancy, has a poor prognosis owing to its high invasiveness and high rate of cervical lymph node metastasis. The tumor microenvironment (TME) is a complex microenvironment that is essential for tumor cell survival. Tumor-associated immune cell (TAIC), the main stromal cell of TME, regulates the proliferation, invasion, epithelial-mesenchymal transformation (EMT), and anti-tumor immunity of OSCC. M2-tumor-associated macrophages (TAMs) promote the invasion and metastasis of OSCC through the macrophage migration inhibitory factor/NOD-like receptor family pyrin domain containing 3/interleukin (IL)-1β axis, while N2-tumor-associated neutrophils (TANs) regulate the proliferation and EMT of OSCC through the Janus kinase 2/signal transducer and activator of transcription 3 pathway. Meanwhile, myeloid-derived suppressor cells (MDSCs) accelerate the progression of OSCC by secreting IL-6, IL-10, and transforming growth factor (TGF)-β; T cells promote inflammation by secreting IL-17 and inhibit inflammation-mediated tumor immune response by secreting IL-10 and TGF-β; and natural killer (NK) cells recognize and attack OSCC cells to inhibit OSCC progression. TAIC interaction network also regulates OSCC progression. M2-TAMs regulate the invasion and metastasis of OSCC by promoting T cell apoptosis through the secretion of IL-10 and programmed death-ligand (PD-L) -1, while N2-TANs inhibit T cell proliferation and cytotoxicity by secreting LOX-1 and arginase-1. MDSCs inhibit the proliferation and anti-tumor effects of CD8⁺ T cells through the inactivation of programmed cell death (PD)-1/PD-L1 signaling. Additionally, MDSCs inhibit the proliferation of T cells by decreasing the expression of the CD3-zeta chain and interferon-γ (IFN-γ). Moreover, tumor-infiltrating lymphocytes and NK cells were found to be positively correlated in OSCC progression. Therefore, target regulation, related signaling pathways, and the interaction network of TAIC may serve as promising therapeutic targets in the immunotherapy of OSCC. In this review, we summarize the recent research on the effects of TAIC and their interaction network in the TME in the progression of OSCC and explore its application in the early diagnosis and treatment of OSCC.

NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome mediates inflammation, induces pyroptosis, and regulates periodontal tissue remodeling through the maturation and secretion of its downstream cysteine protease 1 (Caspase-1)-dependent pro-inflammatory cytokines, interleukin (IL)-1β and IL-18. Orthodontic force mediates the aseptic inflammation of periodontal tissues and triggers adaptive alteration of periodontal tissues, thereby promoting the movement and stability of orthodontic teeth. NLRP3 inflammasome plays an important role in orthodontic tooth movement and causes periodontal tissue inflammation and orthodontic inflammatory root resorption in orthodontic patients. Literature review suggests that NLRP3 inflammasome is involved in the activation and differentiation of periodontal ligament fibroblasts, periodontal ligament stem cells, macrophages, osteoblasts, and osteoclasts in orthodontic tooth mobile tissue remodeling. Additionally, it targets the upstream nuclear factor kappa-B signaling pathway; downstream effectors, such as Caspase-1, IL-1β, and IL-18; and the NLRP3 inflammasome components for regulating tooth movement as well as treating and preventing orthodontics-associated periodontitis and orthodontic-induced inflammatory root resorption. Future studies can be focused on the specific mechanism of NLRP3 inflammasome tissue modification during orthodontic tooth movement. This article reviews the effects and regulatory mechanisms of the NLRP3 inflammasome signaling pathway on the corresponding tissue remodeling during orthodontic tooth movement.