Co-delivery of fucoxanthin and Twist siRNA using hydroxyethyl starch-cholesterol self-assembled polymer nanoparticles for triple-negative breast cancer synergistic therapy.

INTRODUCTION: Triple-negative breast cancer (TNBC) represents the most aggressive subtype of breast cancer with an extremely dismal prognosis and few treatment options. As a desmoplastic tumor, TNBC tumor cells are girdled by stroma composed of cancer-associated fibroblasts (CAFs) and their secreted stromal components. The rapidly proliferating tumor cells, together with the tumor stroma, exert additional solid tissue pressure on tumor vasculature and surrounding tissues, severely obstructing therapeutic agent from deep intratumoral penetration, and resulting in tumor metastasis and treatment resistance. OBJECTIVES: Fucoxanthin (FX), a xanthophyll carotenoid abundant in marine algae, has attracted widespread attention as a promising alternative candidate for tumor prevention and treatment. Twist is a pivotal regulator of epithelial to mesenchymal transition, and its depletion has proven to sensitize antitumor drugs, inhibit metastasis, reduce CAFs activation and the following interstitial deposition, and increase tumor perfusion. The nanodrug delivery system co-encapsulating FX and nucleic acid drug Twist siRNA (siTwist) was expected to form a potent anti-TNBC therapeutic cyclical feedback loop. METHODS AND RESULTS: Herein, our studies constituted a novel self-assembled polymer nanomedicine (siTwist/FX@HES-CH) based on the amino-modified hydroxyethyl starch (HES-NH2) grafted with hydrophobic segment cholesterol (CH). The MTT assay, flow cytometry apoptosis analysis, transwell assay, western blot, and 3D multicellular tumor spheroids growth inhibition assay all showed that siTwist/FX@HES-CH could kill tumor cells and inhibit their metastasis in a synergistic manner. The in vivo anti-TNBC efficacy was demonstrated that siTwist/FX@HES-CH remodeled tumor microenvironment, facilitated interstitial barrier crossing, killed tumor cells synergistically, drastically reduced TNBC orthotopic tumor burden and inhibited lung metastasis. CONCLUSION: Systematic studies revealed that this dual-functional nanomedicine that targets both tumor cells and tumor microenvironment significantly alleviates TNBC orthotopic tumor burden and inhibits lung metastasis, establishing a new paradigm for TNBC therapy.

The enchanting canvas of CAR technology: Unveiling its wonders in non-neoplastic diseases.

Chimeric antigen receptor (CAR) T cells have made a groundbreaking advancement in personalized immunotherapy and achieved widespread success in hematological malignancies. As CAR technology continues to evolve, numerous studies have unveiled its potential far beyond the realm of oncology. This review focuses on the current applications of CAR-based cellular platforms in non-neoplastic indications, such as autoimmune, infectious, fibrotic, and cellular senescence-associated diseases. Furthermore, we delve into the utilization of CARs in non-T cell populations such as natural killer (NK) cells and macrophages, highlighting their therapeutic potential in non-neoplastic conditions and offering the potential for targeted, personalized therapies to improve patient outcomes and enhanced quality of life.

Accuracy of open-sleeved vs. closed-sleeved static computer-assisted implant systems in immediate maxillary molar implant placement: An in vitro study.

OBJECTIVES: The objective of this study is (1) to compare the accuracy of an open-sleeved static computer-assisted implant system (sCAIS) with a closed-sleeve sCAIS and free-hand approach in immediate implant placement (IIP) of maxillary molar sites and (2) to investigate the influence of socket morphology on these approaches. MATERIALS AND METHODS: Ninety partially edentulous duplicated maxillary models simulating three different molar sockets (type A, B, and C based on Smith and Tarnow's classification) were investigated. Three modalities, including sCAIS with open-sleeves, sCAIS with closed-sleeves, and free-hand approach, were applied separately to 30 models with 120 sockets. A customized Python script automatically measured the deviations between the virtual and actual implant positions for all 360 implants. RESULTS: The 3D deviations of sCAIS were significantly influenced by the socket and sleeve types. Both guided groups exhibited significantly less deviation than the free-hand approach. Type A and C sockets resulted in better implant positions than type B socket sites. In type B sockets, the open-sleeve group achieved significantly less deviation compared to the closed-sleeve group, with respect to apical global (1.34 ± 0.53 vs. 1.84 ± 0.59 mm), coronal horizontal (0.68 ± 0.36 vs. 0.93 ± 0.34 mm), apical horizontal (1.21 ± 0.59 vs. 1.74 ± 0.63 mm), and angular (3.30 ± 1.41 vs. 4.41 ± 1.96°) deviations. CONCLUSIONS: Guided implant surgery significantly reduces deviations during molar IIP compared to free-hand procedures. Furthermore, the use of open-sleeve sCAIS appears to be more effective in minimizing deviations in type B sockets when compared with the closed-sleeve guided system.

A Skeleton in a Huff: Insights in Etiologies of Osteosclerosis.

A 30-year-old man developed right lower leg pain and a palpable solid mass. Radiographic imaging revealed a periosteal reaction with an exostotic mass arising from the right distal fibula. Generalized skeletal osteosclerosis with periosteal reaction was discovered on a radiographic skeletal survey. A biopsy of the right fibular mass revealed reactive woven bone. The patient was referred to a metabolic bone disease clinic, where laboratory values were consistent with secondary hyperparathyroidism and increased bone turnover. A DXA bone density scan revealed high bone density, with an L1-4 spine Z-score of +9.3, a left femoral neck Z-score of +8.5, and a total hip Z-score of +6.5. A dental exam revealed generalized gingival inflammation, teeth mobility, generalized horizontal alveolar bone loss and widening of the periodontal ligament space, increased bone density around the teeth, and thickening of the radicular lamina dura. An extensive evaluation was performed, with the result of a single test revealing the diagnosis. The differential diagnoses of osteosclerosis affecting the skeleton, teeth, and oral cavity are discussed.

Targeting autophagy overcomes cancer-intrinsic resistance to CAR-T immunotherapy in B-cell malignancies.

BACKGROUND: Chimeric antigen receptor T (CAR-T) therapy has substantially revolutionized the clinical outcomes of patients with hematologic malignancies, but the cancer-intrinsic mechanisms underlying resistance to CAR-T cells remain yet to be fully understood. This study aims to explore the molecular determinants of cancer cell sensitivity to CAR-T cell-mediated killing and to provide a better understanding of the underlying mechanisms and potential modulation to improve clinical efficacy. METHODS: The human whole-genome CRISPR/Cas9-based knockout screening was conducted to identify key genes that enable cancer cells to evade CD19 CAR-T-cell-mediated killing. The in vitro cytotoxicity assays and evaluation of tumor tissue and bone marrow specimens were further conducted to confirm the role of the key genes in cancer cell susceptibility to CAR-T cells. In addition, the specific mechanisms influencing CAR-T cell-mediated cancer clearance were elucidated in mouse and cellular models. RESULTS: The CRISPR/Cas9-based knockout screening showed that the enrichment of autophagy-related genes (ATG3, BECN1, and RB1CC1) provided protection of cancer cells from CD19 CAR-T cell-mediated cytotoxicity. These findings were further validated by in vitro cytotoxicity assays in cells with genetic and pharmacological inhibition of autophagy. Notably, higher expression of the three autophagy-related proteins in tumor samples was correlated with poorer responsiveness and worse survival in patients with relapsed/refractory B-cell lymphoma after CD19 CAR-T therapy. Bulk RNA sequencing analysis of bone marrow samples from B-cell leukemia patients also suggested the clinical relevance of autophagy to the therapeutic response and relapse after CD19 CAR-T cell therapy. Pharmacological inhibition of autophagy and knockout of RB1CC1 could dramatically sensitize tumor cells to CD19 CAR-T cell-mediated killing in mouse models of both B-cell leukemia and lymphoma. Moreover, our study revealed that cancer-intrinsic autophagy mediates evasion of CAR-T cells via the TNF-α-TNFR1 axis-mediated apoptosis and STAT1/IRF1-induced chemokine signaling activation. CONCLUSIONS: These findings confirm that autophagy signaling in B-cell malignancies is essential for the effective cytotoxic function of CAR-T cells and thereby pave the way for the development of autophagy-targeting strategies to improve the clinical efficacy of CAR-T cell immunotherapy.

Harnessing Biomaterials for Safeguarding Chimeric Antigen Receptor T Cell Therapy: An Artful Expedition in Mitigating Adverse Effects.

Chimeric antigen receptor T cell (CAR-T) therapy has emerged as a groundbreaking approach in cancer treatment, showcasing remarkable efficacy. However, the formidable challenge lies in taming the formidable side effects associated with this innovative therapy, among which cytokine release syndrome (CRS), immune effector cell-associated neurotoxicity syndrome (ICANS) and on-target off-tumor toxicities (OTOT) are typical representatives. Championing the next frontier in cellular immunotherapy, this comprehensive review embarks on an artistic exploration of leveraging biomaterials to meticulously navigate the intricate landscape of CAR-T cell therapy. Unraveling the tapestry of potential toxicities, our discourse unveils a symphony of innovative strategies designed to elevate the safety profile of this revolutionary therapeutic approach. Through the lens of advanced medical science, we illuminate the promise of biomaterial interventions in sculpting a safer and more efficacious path for CAR-T cell therapy, transcending the boundaries of conventional treatment paradigms.

Recommendations for successful virtual patient-assisted esthetic implant rehabilitation: A guide for optimal function and clinical efficiency.

OBJECTIVE: Complete arch implant rehabilitation necessitates meticulous treatment planning and high-level collaboration between surgical and prosthetic dental teams. Emerging virtual technologies hold considerable promise in streamlining this process. The aim of this article is to extend recommendations to clinicians venturing into the virtual patient-assisted esthetic implant rehabilitation workflow. OVERVIEW: This article summarizes recommendations for virtual patient-assisted esthetic implant rehabilitation in the following five aspects: three-dimensional data handling and superimposition, occlusion and virtual articulator integration in creating virtual patients, streamlined face- and prosthetic-driven surgical planning, reuse of presurgical data ("Copy & Paste"), and final impression for passive fitting of final restoration. To illustrate these principles, a case with complete-mouth implant rehabilitation completed within six visits using this virtual patient workflow is presented. CONCLUSION: The virtual patient workflow serves as an invaluable tool to perform treatment planning, enhance efficiency, and ensure predictable outcomes in esthetic complete arch implant rehabilitation. CLINICAL SIGNIFICANCE: Virtual workflows are increasingly prevalent in esthetic implant rehabilitation. Nevertheless, these workflows necessitate a distinct set of knowledge and tools divergent from conventional dentistry practices. This article offers guidelines and recommendations for dental clinicians who are new to this field.

Enhancing the Treatment of Uncontrolled Inflammation through the Targeted Delivery of TPCA-1-Loaded Nanoparticles.

Uncontrolled inflammation is a pathological state that underlies many diseases. Despite the development of numerous anti-inflammatory agents, the treatment of uncontrolled inflammation remains a challenging task. We developed a targeted delivery system for [5-(p-fluorophenyl)-2-ureido]thiophene-3-carboxamide (TPCA-1), a potent inhibitor of the NF-κB signaling pathway. The system comprises TPCA-1-loaded nanoparticles (NPs) functionalized with a monoclonal antibody (mAb) that specifically binds to the break point of the IgD6 region of the platelet/endothelial cell adhesion molecule-1 (PECAM-1) extracellular segment that is overexposed on the injured endothelium and activated macrophages during the pathogenesis of inflammation. In vitro binding and cellular uptake experiments revealed that the mAb modification on NPs could significantly enhance uptake by both Raw264.7 and HUVEC compared with unmodified NPs. In studies conducted at the cellular level focusing on anti-inflammatory and antioxidant effects, this formulation was found to effectively inhibit M1 polarization of macrophages, downregulate the secretion of pro-inflammatory cytokines, and reduce the production of reactive oxygen species (ROS) and nitric oxide (NO). In an animal model of vascular endothelial injury with acute inflammation, these NPs were capable of delivering TPCA-1 to inflammatory lesions in a targeted manner. Compared with the free agent-treated group, the NP-treated group exhibited reduced infiltration of inflammatory cells. In conclusion, our study demonstrates that this targeted delivery of TPCA-1-loaded NPs represents a promising strategy for improved mitigation of uncontrolled inflammation.

Advances in CAR-Engineered Immune Cell Generation: Engineering Approaches and Sourcing Strategies.

Chimeric antigen receptor T-cell (CAR-T) therapy has emerged as a highly efficacious treatment modality for refractory and relapsed hematopoietic malignancies in recent years. Furthermore, CAR technologies for cancer immunotherapy have expanded from CAR-T to CAR-natural killer cell (CAR-NK), CAR-cytokine-induced killer cell (CAR-CIK), and CAR-macrophage (CAR-MΦ) therapy. Nevertheless, the high cost and complex manufacturing processes of ex vivo generation of autologous CAR products have hampered broader application. There is an urgent need to develop an efficient and economical paradigm shift for exploring new sourcing strategies and engineering approaches toward generating CAR-engineered immune cells to benefit cancer patients. Currently, researchers are actively investigating various strategies to optimize the preparation and sourcing of these potent immunotherapeutic agents. In this work, the latest research progress is summarized. Perspectives on the future of CAR-engineered immune cell manufacturing are provided, and the engineering approaches, and diverse sources used for their development are focused upon.

circ_SPEF2 Regulates the Balance of Treg Cells by Regulating miR-16-5p/BACH2 in Lymphoma and Participates in the Immune Response.

BACKGROUND: This study aims to explore the potential mechanism of action of the newly discovered hsa_circ_0128899 (circSPEF2) in diffuse large B-cell lymphoma (DLBCL). METHODS: circSPEF2, miR-16-5p and BTB and CNC homologue 2 (BACH2) expression patterns in DLBCL patients and cell lines were studied by RT-qPCR. The biological function of circSPEF2 in vitro and in vivo was investigated by function acquisition experiments. The proliferation activity of lymphoma cells was detected by MTT. Bax, Caspase-3, and Bcl-2 were determined by Western Blot. Apoptosis and the ratio of CD4 to Treg of immune cells in the co-culture system were analyzed by flow cytometry. The mechanism of action of circSPEF2 in DLBCL progression was further investigated by RIP and dual luciferase reporter experiments. RESULTS: circSPEF2 was a circRNA with abnormally down-regulated expression in DLBCL. Increasing circSPEF2 expression inhibited the proliferative activity and induced apoptosis of lymphoma cells in vitro and in vivo, as well as increased CD4+T cells and decreased Treg cell proportion of immune cells in the tumor microenvironment. Mechanically, circSPEF2 was bound to miR-16-5p expression, while BACH2 was targeted by miR-16-5p. circSPEF2 overexpression-mediated effects on lymphoma progression were reversible by upregulating miR-16-5p or downregulating BACH2. CONCLUSIONS: circSPEF2 can influence DLBCL progression by managing cellular proliferation and apoptosis and the proportion of immune cells Treg and CD4 through the miR-16-5p/BACH2 axis.

Prosthetic articulator-based implant rehabilitation virtual patient: A technique bridging implant surgery and reconstructive dentistry.

This technique report describes a fully digital workflow to create a prosthetic articulator-based implant rehabilitation (PAIR) virtual patient for complete-arch or complete-mouth implant rehabilitation. This workflow uses a custom gothic arch tracer during the cone beam computed tomography (CBCT) scan and a 3-dimensional virtual facebow when superimposing data. The PAIR virtual patient possesses reliable centric relation and vertical dimension of occlusion and is compatible with virtual articulators. Computer-aided implant planning and a digital prosthetic design can be seamlessly integrated by using this virtual patient.

Soft tissue phenotype modification impacts on peri-implant stability: a comparative cohort study.

OBJECTIVES: Soft tissue phenotype modification (STPM) could be performed to maintain peri-implant health. Therefore, the aim of the study was to analyze tissue alteration around implants following soft tissue phenotype modification during implant uncovering surgery. MATERIALS AND METHODS: Patients who had STPM (either pouch roll or modified roll technique) during implant second-stage surgery with at least 12-month follow-up were included. Clinical and radiographic parameters including mucosal tissue thickness (MTT), recession (REC), keratinized mucosa width (KMW), probing pocket depth (PPD), marginal bone loss (MBL), emergence profile, and emergence angle were extracted from 2-week, 2-month, and 12-month visits after second-stage surgery. RESULTS: Twenty-eight patients with 33 implants that fulfilled the inclusion criteria were included. After soft tissue phenotype modification, at 2 weeks, REC was negatively correlated to mean MTT at mid-buccal site (r = - 0.41, p = 0.018) and borderline correlated at mid-lingual site (r = - 0.343, p = 0.051). Stable KMW was maintained from 2 weeks to 12 months with minimal shrinkage rate (3 ~ 14%). MBL change was limited (0.24 ~ 0.47 mm) after STPM. All implants had shallow PPD (≤ 3 mm) with the absence of bleeding on probing. Emergence angle at the mesial side, however, was significantly correlated to surgical techniques, which indicated pouch roll technique would have 6.96 degrees more than modified roll technique (p = 0.024). CONCLUSIONS: Soft tissue phenotype modification, either pouch roll or modified roll technique, during uncovering surgery resulted in favorable clinical outcomes. Thin mucosal tissue thickness and pouch roll technique are the factors related to more recession at 2 weeks. Pouch roll technique could influence the restorative design by having a wide emergence angle at the mesial side. CLINICAL RELEVANCE: Modified and pouch roll techniques during uncovering surgery were viable methods to yield favorable peri-implant health, while the preciseness of pouch roll technique was required to avoid mucosal recession and inadequate restorative design.

Accuracy of Intraoperative Measuring Guide and Conventional Surgical Guide in Anterior Implant Surgery: A Retrospective Case-Control Study

PURPOSE: To verify a novel method that improves the accuracy of static computer-aided implant surgery (sCAIS) through intraoperative measurement. MATERIALS AND METHODS: Forty-seven patients were selected for this study, each with a missing tooth or a tooth that required extraction from the anterior area. The patients were divided into the intraoperative measuring guide (MG) and conventional guide (CG) groups. Following the preoperative implant planning, the surgical guides were designed and fabricated. In the MG group, the drill was guided by double-armed zirconia sleeves, and the axial direction of the drill was assessed using the indicator components. The implant was guided using a resin guide tube. In the CG group, the drills were guided using a metal sleeve and handles, and the implants were placed with the guidance of the metal sleeve only. The angular and linear deviations at the entry and apex between the planned and actual implant positions were measured after matching the preoperative and postoperative CBCT data. The independent-samples t test was used to compare the deviation between the MG and CG groups. RESULTS: The 3D deviations for the MG group at the entry and apex were 0.67 ± 0.44 mm and 0.93 ± 0.40 mm, respectively. The angular deviation was 2.27 ± 0.96 degrees. Statistical differences were found in the 3D deviation at the entry point and apical position between the MG and CG groups, yielding relatively smaller deviations in the MG group. CONCLUSION: The use of an intraoperative measuring guide could improve the accuracy of implant placement in sCAIS.

Orthologous genes Pm12 and Pm21 from two wild relatives of wheat show evolutionary conservation but divergent powdery mildew resistance.

Wheat powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is a devastating disease that threatens wheat production worldwide. Pm12, which originated from Aegilops speltoides, a wild relative of wheat, confers strong resistance to powdery mildew and therefore has potential use in wheat breeding. Using susceptible mutants induced by gamma irradiation, we physically mapped and isolated Pm12 and showed it to be orthologous to Pm21 from Dasypyrum villosum, also a wild relative of wheat. The resistance function of Pm12 was validated via ethyl methanesulfonate mutagenesis, virus-induced gene silencing, and stable genetic transformation. Evolutionary analysis indicates that the Pm12/Pm21 loci in wheat species are relatively conserved but dynamic. Here, we demonstrated that the two orthologous genes, Pm12 and Pm21, possess differential resistance against the same set of Bgt isolates. Overexpression of the coiled-coil domains of both PM12 and PM21 induces cell death in Nicotiana benthamiana leaves. However, their full-length forms display different cell death-inducing activities caused by their distinct intramolecular interactions. Cloning of Pm12 will facilitate its application in wheat breeding programs. This study also gives new insight into two orthologous resistance genes, Pm12 and Pm21, which show different race specificities and intramolecular interaction patterns.

The Impact of Implantoplasty in Regenerated and Nonregenerated Treatment Modalities in Peri-implantitis: A Systematic Review and Meta-analysis.

PURPOSE: To investigate the impact of implantoplasty (IP) with or without regenerative procedures on treatment outcomes of peri-implantitis. MATERIALS AND METHODS: Electronic and manual literature searches were conducted for clinical trials published up to October 2020 that evaluated clinical outcomes (at least 6-month follow-up) after peri-implantitis treatment involving IP. The implant survival rate and clinical parameters (eg, probing depth [PD], bleeding on probing [BOP], marginal bone loss [MBL], clinical attachment level [CAL], and mucosal recession [REC]) at baseline and follow-ups were extracted from original articles for qualitative analyses. Risk ratio and weighted mean difference with 95% CI were calculated using a random-effects model. RESULTS: Out of 322 studies, 17 (9 randomized controlled trials, 4 controlled clinical trials, and 4 case series) were included in the present study. The regeneration group presented a 97% (95% CI: 0.95 to 1.00) implant survival rate, and the nonregeneration group showed a 94% (95% CI: 0.90 to 0.98) survival rate. Both groups revealed similar outcomes in PD and BOP reductions and soft tissue REC. However, the regeneration group had more favorable results in MBL. CONCLUSION: Data from this study suggested that applying implantoplasty during a regeneration or nonregeneration surgical approach resulted in a high implant survival rate and peri-implantitis resolution. Although no differences were found in the majority of clinical parameters in both groups, the regenerative approach resulted in more radiographic bone fill than the nonregenerative treatment.

Large-scale mutational analysis of wheat powdery mildew resistance gene Pm21.

Wheat powdery mildew is a devastating disease leading to severe yield loss. The powdery mildew resistance gene Pm21, encoding a nucleotide-binding leucine-rich repeat receptor (NLR) protein, confers broad-spectrum resistance to powdery mildew and has great potential for controlling this disease. In this study, a large-scale mutagenesis was conducted on wheat cultivar (cv.) Yangmai 18 carrying Pm21. As a result, a total of 113 independent mutant lines susceptible to powdery mildew were obtained, among which, only one lost the whole Pm21 locus and the other 112 harbored one- (107) or two-base (5) mutations in the encoding region of Pm21. From the 107 susceptible mutants containing one-base change, we found that 25 resulted in premature stop codons leading to truncated proteins and 82 led to amino acid changes involving in 59 functional sites. We determined the mutations per one hundred amino acids (MPHA) indexes of different domains, motifs, and non-domain and non-motif regions of PM21 protein and found that the loss-of-function mutations occurred in a tendentious means. We also observed a new mutation hotspot that was closely linked to RNBS-D motif of the NB-ARC domain and relatively conserved in different NLRs of wheat crops. In addition, we crossed all the susceptible mutants with Yangmai 18 carrying wild-type Pm21, subsequently phenotyped their F1 plants and revealed that the variant E44K in the coiled-coil (CC) domain could lead to dominant-negative effect. This study revealed key functional sites of PM21 and their distribution characteristics, which would contribute to understanding the relationship of resistance and structure of Pm21-encoded NLR.

Open-sleeve templates for computer-assisted implant surgery at healed or extraction sockets: An in vitro comparison to closed-sleeve guided system and free-hand approach.

OBJECTIVE: A buccal opening guide provides better view and better irrigation. The aim of this study was to investigate the accuracy of this open-sleeve system. MATERIAL AND METHODS: Thirty duplicated maxillary models, each with six extraction sockets and four healed sites, were used. Based on the same digital plan, three modalities, sCAIS with open-sleeves, closed-sleeves, and free-hand approach, were used to place implants. The global, horizontal, depth, and angular deviations between the virtual and actual implant positions were measured. RESULTS: Both sCAIS groups exhibited better accuracy than the free-hand group in two clinical scenarios. At healed sites, the closed-sleeve group showed a significantly fewer error than the open-sleeve group in global apical (0.68 ± 0.33 vs. 0.96 ± 0.49 mm), horizontal coronal (0.28 ± 0.15 vs. 0.44 ± 0.25 mm), horizontal apical (0.64 ± 0.32 vs. 0.94 ± 0.48 mm), and angular deviations (1.83 ± 0.95 vs. 2.86 ± 1.46°). For extraction sockets, the open-sleeve group exhibited fewer deviations than the closed-sleeve group in terms of global (coronal: 0.77 ± 0.29 vs. 0.91 ± 0.22 mm; apical: 1.08 ± 0.49 vs. 1.37 ± 0.52 mm) and horizontal (coronal: 0.60 ± 0.24 vs. 0.86 ± 0.20 mm; apical: 0.95 ± 0.50 vs. 1.32 ± 0.51 mm) deviations. However, the closed-sleeve group was more accurate in the depth control (0.26 ± 0.20 vs. 0.40 ± 0.31 mm). CONCLUSION: In this in vitro investigation, open-sleeve sCAIS proved better accuracy than free-hand surgery for both delayed and immediate implant placement. Compared with a closed-sleeve sCAIS system, open sleeve have the potential of providing better outcomes in extraction sockets but not in healed sites.

Does guided level (fully or partially) influence implant placement accuracy at post-extraction sockets and healed sites? An in vitro study.

OBJECTIVES: The aim of this study is to evaluate the effect of guide level on the accuracy of static computer-aided implant surgery (sCAIS) at post-extraction sockets and healed sites. MATERIALS AND METHODS: A total of 30 duplicate dental models, with 300 potential implant sites, were used. All the models were equally randomized into three groups: fully guided (FG, n = 100), partially guided (PG, n = 100), and free handed (FH, n = 100) surgeries. After implant placement, the mean global, horizontal, depth, and angular deviations between the virtually planned and actual implant positions were measured automatically by a Python script within software Blender. RESULTS: Both FG and PG surgeries showed significantly higher accuracy than FH surgery at post-extraction sockets and healed sites. In both sCAIS groups, there were nearly 50% more deviations from implants placed at sockets than those from delayed placement. For the immediate implant placement, the accuracy of sCAIS was significantly affected by the level of guidance. The FG group exhibited lower deviations than the PG group, with a significant difference in coronal global and horizontal deviations (p < .05). For the healed sites, two guided groups exhibited similar outcomes (p > .05). CONCLUSIONS: sCAISs provide more accuracy than the free-handed approach in position transferring from planning to a model simulation. Full guidance can significantly increase the accuracy, especially at post-extraction sites. CLINICAL RELEVANCE: Guided protocols showed significantly higher accuracy than free-handed surgery regardless of implantation timing, but both had nearly 50% more deviations in immediate implant placement.

Improvement in Osseointegration of Titanium Dental Implants After Exposure to Ultraviolet-C Light for Varied Durations: An Experimental Study in Beagle Dogs.

PURPOSE: Ultraviolet-mediated photofunctionalization is a valid technology for enhancing the osseointegration of titanium implants. However, there is no consensus on the effective exposure time to ultraviolet light. The objective of this study was to evaluate the effect of different exposure times of ultraviolet-C (UVC) light on aged titanium implants and explore the optimal treatment duration of UVC photofunctionalization for osseointegration in an animal model. METHODS: Eight male beagle dogs (n = 48) were divided into a control group (n = 12) and 3 experimental groups (n = 12/12/12) which received 4-week-old implants without UVC treatment (C) or treated with UVC for 1/6 hour, 1/2 hour, and 1 hour (UVC-1/6 hour, UVC-1/2 hour, UVC-1 hour) immediately before placement. All the implants were placed 12 weeks after mandibular premolars extraction. Four dogs were euthanized after 4 and 12 weeks of healing, respectively. The marginal bone level and implant stability quotient were measured at implant placement and after sacrifice. Subsequently, micro-CT and histomorphometric analyses were performed following block harvesting. RESULTS: No significant difference in marginal bone loss between the UVC-untreated and UVC-treated groups was found at 4 or 12 weeks. At 4 weeks, significantly higher BV/TV and bone-implant contact were observed in the UVC groups than in the C group, irrespective of the UVC-photofunctionalization duration (BV/TV: UVC-1/6 hour 0.48 ± 0.11, UVC-1/2 hour 0.50 ± 0.06, and UVC-1 hour 0.47 ± 0.08, C 0.34 ± 0.04; bone-implant contact : UVC-1/6 hour 84.30 ± 5.02%, UVC-1/2 hour 85.82 ± 5.05%, and UVC-1 hour 84.98 ± 3.86%, C 71.69 ± 3.52%. P < .05), whereas, no significant difference was observed among the UVC groups. At 12 weeks, there were no significant differences between the C group and UVC groups. After 4 and 12 weeks of healing, no significant difference in implant stability quotient values was observed between the C group and UVC groups. CONCLUSIONS: UVC photofunctionalization improved the early osseointegration of aged titanium implants. However, the effect was not dependent on the UVC-light duration within the range from 1/6 hour to 1 hour.

Assessment of a Novel Alveolar Ridge Preservation Concept in Dehiscence Sockets: A Pilot Study.

In this prospective pilot study on ridge preservation (RP), a collagen sponge was placed to fill the bottom half of the socket, followed by a sequence of bone graft, collagen membrane, and a sponge placed on top. Twelve patients with 13 hopeless posterior teeth were included. Changes in bone dimension (including variations of horizontal ridge width [HRW] and bone height [BH]) between the time immediately postextraction (T0) and 6 months later (T6M) were evaluated through CBCT. The soft tissue was assessed using a wound healing index (WHI) at 2 weeks (T2W), 2 months (T2M), and 6 months (T6M) postsurgery. Measured at three parallel levels (1, 3, and 5 mm apical to the crest of the palatal plate), the mean HRW changes (T0 to T6M) ranged from 0.47 to 1.05 mm. Statistically significant negative correlations were observed between WHI (T6M) and midcrestal BH change. This proposed RP technique showed favorable outcomes regarding HRW and BH, even in periodontally compromised dehiscence sockets.