Accuracy analysis of robotic-assisted immediate implant placement: A retrospective case series.

OBJECTIVES: This study aimed to investigate the accuracy of a robotic computer-assisted implant surgery (r-CAIS) for immediate implant placement. METHODS: Patients requiring immediate implant placement in the maxillary anterior region were enrolled for r-CAIS. Before surgery, the patients underwent a cone beam computed tomography (CBCT) scan with a positioning marker. Virtual implant placement position and drilling sequences were planned. Following spatial registration and calibration, the implants were placed with the robotic system under supervision. A postoperative CBCT was taken to control the actual implant positions. The DICOM data of the virtually planned and the actually placed implant were superimposed and registered through the accuracy verification software of the robotic system. The accuracy was calculated automatically. The deviation at the mesial-distal, labial-palatal, and apico-coronal directions were recorded. RESULTS: Fifteen patients with 20 implants were included. No adverse surgical events or postoperative complications were reported. The global platform, apex, and angular deviation were 0.75 ± 0.20 mm (95 % CI: 0.65 to 0.84 mm), 0.70 ± 0.27 mm (95 % CI: 0.57 to 0.82 mm), and 1.17 ± 0.73° (95 % CI: 0.83 to 1.51°), respectively. Moreover, the vertical platform and apex deviation were 0.50 ± 0.31 mm, (95 % CI: 0.35 to 0.64 mm) and 0.48 ± 0.32 mm, (95 % CI: 0.33 to 0.63 mm), respectively. All the placed implant positions were further labial and apical than the planned ones, respectively. CONCLUSIONS: High accuracy of immediate implant placement was achieved with the robotic system. CLINICAL SIGNIFICANCE: Our study provided evidence to support the potential of the robotic system in implant placement, even in challenging scenarios.

Accuracy of dynamic navigation compared to static surgical guides and the freehand approach in implant placement: a prospective clinical study.

BACKGROUND: Computer-guided implant surgery has improved the quality of implant treatment by facilitating the placement of implants in a more accurate manner. This study aimed to assess the accuracy of implant placement in a clinical setting using three techniques: dynamic navigation, static surgical guides, and freehand placement. We also investigated potential factors influencing accuracy to provide a comprehensive evaluation of each technique's advantages and disadvantages. MATERIALS AND METHODS: Ninety-four implants in 65 patients were included in this prospective study. Patients were randomly assigned to one of three groups: dynamic navigation, static surgical guides, or freehand placement. Implants were placed using a prosthetically oriented digital implant planning approach, and postoperative CBCT scans were superimposed on preoperative plans to measure accuracy. Seven deviation values were calculated, including angular, platform, and apical deviations. Demographic and consistency analyses were performed, along with one-way ANOVA and post-hoc tests for deviation values. RESULTS: The mean global platform, global apical, and angular deviations were 0.99 mm (SD 0.52), 1.14 mm (SD 0.56), and 3.66° (SD 1.64°) for the dynamic navigation group; 0.92 mm (SD 0.36), 1.06 mm (SD 0.47), and 2.52° (SD 1.18°) for the surgical guide group; and 1.36 mm (SD 0.62), 1.73 mm (SD 0.66), and 5.82° (SD 2.79°) for the freehand group. Both the dynamic navigation and surgical guide groups exhibited statistically significant differences in all values except depth deviations compared to the freehand group (p < 0.05), whereas only the angular deviation showed a significant difference between the dynamic navigation and surgical guide groups (p = 0.002). CONCLUSION: Our findings highlight the superior accuracy and consistency of dynamic navigation and static surgical guides compared to freehand placement in implant surgery. Dynamic navigation offers precision and flexibility. However, it comes with cost and convenience considerations. Future research should focus on improving its practicality. TRIAL REGISTRATION: This study was retrospectively registered at the Thai Clinical Trials Register-Medical Research Foundation of Thailand (MRF) with the TCTR identification number TCTR20230804001 on 04/08/2023. It was also conducted in accordance with the Declaration of Helsinki and approved by the institutional ethics committee at the Xian Jiaotong University Hospital of Stomatology, Xian, China (xjkqII[2021] No: 043). Written informed consent was obtained from all participants.

Prognostic value of ultrasound in early arterial complications post liver transplant.

Liver transplantation is the primary therapeutic intervention for end-stage liver disease. However, vascular complications, particularly those involving the hepatic artery, pose significant risks to patients. The clinical manifestations associated with early arterial complications following liver transplantation are often nonspecific. Without timely intervention, these complications can result in graft failure or patient mortality. Therefore, early diagnosis and the formulation of an optimal treatment plan are imperative. Ultrasound examination remains the predominant imaging modality for detecting complications post liver transplantation. This article comprehensively reviews common causes and clinical presentations of early hepatic artery complications in the post-transplantation period and delineates abnormal sonographic findings for accurate diagnosis of these conditions. Overall, ultrasound offers the advantages of convenience, safety, effectiveness, and non-invasiveness. It enables real-time, dynamic, and precise evaluation, making it the preferred diagnostic method for post-liver transplantation assessments.

Investigation of the Pressure Gain Characteristics and Cycle Performance in Gas Turbines Based on Interstage Bleeding Rotating Detonation Combustion.

To further improve the cycle performance of gas turbines, a gas turbine cycle model based on interstage bleeding rotating detonation combustion was established using methane as fuel. Combined with a series of two-dimensional numerical simulations of a rotating detonation combustor (RDC) and calculations of cycle parameters, the pressure gain characteristics and cycle performance were investigated at different compressor pressure ratios in the study. The results showed that pressure gain characteristic of interstage bleeding RDC contributed to an obvious performance improvement in the rotating detonation gas turbine cycle compared with the conventional gas turbine cycle. The decrease of compressor pressure ratio had a positive influence on the performance improvement in the rotating detonation gas turbine cycle. With the decrease of compressor pressure ratio, the pressurization ratio of the RDC increased and finally made the power generation and cycle efficiency enhancement rates display uptrends. Under the calculated conditions, the pressurization ratios of RDC were all higher than 1.77, the decreases of turbine inlet total temperature were all more than 19 K, the power generation enhancements were all beyond 400 kW and the cycle efficiency enhancement rates were all greater than 6.72%.

[Research on the intervention of Yishen Huoxue prescription to renal fibrosis through the signal regulation by microRNA-126 to VEGF-Notch].

OBJECTIVE: To explore the molecular mechanism of Yishen Huoxue prescription in delaying the development of renal fibrosis by regulating the microRNA-126/vascular endothelial growth factor-Notch (miR-126/VEGF-Notch) signaling pathway. METHODS: Ninety male Sprague-Dawley (SD) rats were randomly divided into sham operation group (sham group), unilateral ureteral obstruction (UUO) model group, losartan group (50 mg×kg-1×d-1) and high, medium and low doses Yishen Huoxue prescription group (25.2, 12.6, 6.3 mL/kg). Each treatment group began to administer drugs by gavage on the day when UUO modeling was finished until the end of the experiment. Left renal tissues of rats were harvested after 7, 14 and 21 days postoperatively. The pathological changes of renal tissue were observed after hematoxylin and eosin (HE) and Masson staining under the microscope, and the renal fibrosis score was calculated. The mRNA expressions of renal tissues miR-126, VEGFA, vascular endothelial growth factor receptor-2 (VEGFR-2), Notch1 were detected by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: (1) Pathology results: the kidney tissue of sham group was normal. In UUO model group, renal tubules expanded and inflammatory cells in renal interstitium increased; renal tubulointerstitial fibrosis could be seen 7 days after operation, and the degree of fibrosis was gradually increased with time. The renal fibrosis score at each time point after operation in UUO model group was significantly higher than that in sham group. Compared with UUO model group, each treatment group were improved the degree of renal swelling and atrophy of renal parenchyma; the score of renal fibrosis were significantly decreased in the middle and high doses Yishen Huoxue prescription group and losartan group at the 7th day after operation (1.00±1.00, 0.91±0.58, 1.01±0.58 vs. 2.00±0.00, all P < 0.01); but there was no significant difference between low dose Yishen Huoxue prescription group and UUO model group. (2) RT-PCR results: Compared with sham group, the mRNA expressions of miR-126, VEGFA, VEGFR-2 and Notch1 in renal tissues were significantly increased at each time point after operation in UUO model group. Compared with the UUO model group, the mRNA expressions of miR-126, VEGFA, VEGFR-2 and Notch1 in renal tissue of 7 days postoperatively in the middle and high doses Yishen Huoxue prescription group and the losartan group were significantly increased [miR-126 (2-ΔΔCt): 0.465±0.067, 0.639±0.092, 0.404±0.069 vs. 0.132±0.021; VEGFA (2-ΔΔCt): 0.024±0.005, 0.027±0.007, 0.023±0.006 vs. 0.014±0.006; VEGFR-2 (2-ΔΔCt): 0.021±0.007, 0.023±0.008, 0.019±0.007 vs. 0.012±0.004; Notch1 (2-ΔΔCt): 0.017±0.004, 0.020±0.005, 0.018±0.005 vs. 0.007±0.004; all P < 0.05]; compared with the losartan group, the mRNA expressions of each index in the middle and high doses Yishen Huoxue prescription group were increased at all the time points, but there was no significant difference between them (all P > 0.05). There was no significant difference in mRNA expression of each index between low dose Yishen Huoxue prescription group and UUO model group. CONCLUSIONS: The medium and high doses of Yishen Huoxue prescription can effectively antagonize renal fibrosis. Yishen Huoxue prescription may use up-regulation the signaling pathways of miR-126/VEGF-Notch to mediate renal microvascular newly born, eventually to improve renal microvascular damage and delay the development of renal fibrosis progression.

Influences of Schneiderian membrane conditions on the early outcomes of osteotome sinus floor elevation technique: a prospective cohort study in the healing period.

OBJECTIVES: To radiographically investigate early outcomes of osteotome sinus floor elevation in the healing phase utilizing cone beam computed tomography and evaluate influences of Schneiderian membrane conditions. MATERIAL AND METHODS: One hundred patients were consecutively recruited for osteotome sinus floor elevation (OSFE) surgery using deproteinized bone mineral. CBCT was taken prior to (T0), immediately post-operatively (T1), and after the healing period (T2). Linear and volumetric measurements of the elevated region from T0 to T1 were performed for evaluation on computed tomography (CT). RESULTS: Osteotome sinus floor elevation were performed in 100 patients. One implant of each patient was selected. Mean residual bone height (RH) was 7.21 ± 1.12 mm. Mean sinus floor elevation height (SE) was 4.81 ± 0.75 mm. The mean endo-sinus bone gain after the healing period was 3.25 ± 0.83 mm. Pre-opterative CBCT scans revealed that 72 patients had a normal sinus membrane in osteotome region, 13 patients presented with flat thickened mucosa and 15 patients with antral pseudocysts. There is no significant difference in sinus mucosa elevation height, bone graft volume and new bone formation in group of Thickening membrane and Antral pseudocysts compared with normal. CONCLUSIONS: The radiographical results show that OSFE is a safe and predictable surgical procedure in residual bone height of 7.21 ± 1.12 mm. Mild flat thickening (>2 and <5 mm) and antral pseudocysts in a small size without clinical symptoms may not be contraindications to OSFE surgery.

Effect of molecular weight and concentration of hyaluronan on cell proliferation and osteogenic differentiation in vitro.

Hyaluronan (HA), the simplest glycosaminoglycan and a major component of the extracellular matrix, exists in various tissues. It is involved in some critical biological procedures, including cellular signaling, cell adhesion and proliferation, and cell differentiation. The effect of molecular weight (MW) and concentration of HA on cell proliferation and differentiation was controversial. In this study, we investigated the effect of MW and concentration of HA on the proliferation and osteogenic differentiation of rabbit bone marrow-derived stem cells in vitro. Results showed that high MW HA decreased the cell adhesion rate in a concentration-dependant manner. The cell adhesion rate was decreased by increasing MW of HA. Cell proliferation was significantly enhanced by low MW HA (P < 0.05). The factorial analysis indicated that MW and concentration had an interactive effect on the cell adhesion rate and cell proliferation (P < 0.05). High MW HA increased the mRNA expressions of ALP, RUNX-2 and OCN. The higher the MW was, the higher the mRNA expressions were. The factorial analysis indicated that MW and concentration had an interactive effect on ALP mRNA expression (P < 0.05). HA of higher MW and higher concentration promoted bone formation. These findings provide some useful information in understanding the mechanism underlying the effect of MW and concentration of HA on cell proliferation and differentiation.

Characteristics and Tissue Regeneration Properties of Gingiva-Derived Mesenchymal Stem Cells.

Mesenchymal stem cells (MSCs) have 2 specific characteristics: self-renewal and multi- or pluripotency. Extensive studies have demonstrated the regenerative capability of MSCs both in vitro and in vivo. Gingiva-derived MSCs (GMSCs) represent a unique population of MSCs that can be easily isolated and obtained. GMSCs, which maintain a normal karyotype and telomerase activity in long-term cultures, display a stable phenotype and rapidly proliferate in vitro. In addition, GMSCs can be induced to differentiate into osteogenic, chondrogenic, and adipogenic lineages. Therefore, GMSCs are a promising alternative cell source for tissue regeneration in dentistry. In this article we review studies of the characterization, differentiation capacities, and regenerative role of GMSCs derived from the gingiva of humans and other species, focusing on the mechanisms of differentiation and tissue regeneration of human GMSCs. We anticipate that GMSC-based therapies will significantly contribute to regenerative medicine for the treatment of human dental diseases and improve human health.

Circadian variations of clock gene Per2 and cell cycle genes in different stages of carcinogenesis in golden hamster buccal mucosa.

Previous studies have suggested that the expression of clock genes have circadian rhythms, and many cell cycle genes are regulated by clock genes. The disruption of circadian rhythms appears to be associated with the acceleration of cancer development. To investigate the circadian patterns of the clock gene Per2 and of cell cycle genes p53, Cyclin D1, CDK1 and Cyclin B1 in different stages of carcinogenesis, the daily mRNA profiles of these genes were detected by real-time RT-PCR in dimethylbenzanthracene-induced cancer, in precancerous lesions and in normal tissues. Per2, p53, Cyclin D1 and CDK1 showed circadian rhythms in the 3 different stages of carcinogenesis, whereas the circadian rhythm of Cyclin B1 was absent in the precancerous lesions. The mesors and amplitudes of Per2 and p53 were decreased (P < 0.05), but the mesors of Cyclin D1, CDK1 and Cyclin B1 were increased with the development of cancer (P < 0.05). Compared with the normal tissues, the acrophases of Per2 and CDK1 were earlier in precancerous lesions, and the acrophases of Cyclin D1, CDK1 and Cyclin B1 occurred later in the cancer cells. Our study represents the first demonstration of the circadian pattern variations of these genes in different stages of carcinogenesis.

The drug efficacy and adverse reactions in a mouse model of oral squamous cell carcinoma treated with oxaliplatin at different time points during a day.

BACKGROUND: Recent studies have shown that the growth and proliferation of cancer cells in vivo exhibit circadian rhythm, and the efficacy and adverse reactions of platinum-based anticancer drugs administered at different times of the day vary significantly on colon cancer. However, since the circadian rhythms of growth and proliferation of various cancer cells often differ, the question of whether the administration of platinum anticancer drugs at different times of the day exerts significantly different efficacy and adverse effects on oral cancers remains to be elucidated. This study has compared the efficacy and adverse effects of oxaliplatin (L-OHP) administration at different times during a day on oral squamous cell carcinoma in mice and has analyzed cellular circadian rhythms. METHODS: The mouse model for oral squamous cell carcinoma was established in 75 nude mice, housed in a 12 hour light/12 hour dark cycle environment. The mice were randomly divided into five groups; four experimental groups were intravenously injected with L-OHP at four time points within a 24-hour period (4, 10, 16, and 22 hours after lights on [HALO]). The control group was intravenously injected with the same volume of saline. Treatment efficacy and adverse reactions were compared on the seventh day after the injection, at 22 HALO. The existence of circadian rhythms was determined by cosine analysis. RESULTS: Only injections of L-OHP at 16 and 22 HALO significantly prolonged animal survival time. The adverse reactions in mice injected with L-OHP at 16 and 22 HALO were significantly less than those observed in mice administered L-OHP at 4 and 10 HALO. The cosine fitting curve showed that the survival time and adverse reactions exhibited circadian rhythm. CONCLUSION: The time factor should be considered when treating patients with oral squamous cell carcinoma with L-OHP in order to achieve better efficacy, reduce the adverse reactions, and improve the patients' survival time and quality of life.

[Chronchemotherapy of oxaliplatin to oral squamous cell carcinoma].

OBJECTIVE: To compare the differences of the efficacy and adverse reaction of Oxaliplatin (L-OHP) treatment to oral squamous cell carcinoma (OSCC) at four different daily time points, and to analyze the characteristics of circadian rhythms. METHODS: Seventy-five nude mice were placed under 12h light and 12h dark cycles. Human OSCC cell line BcaCD885 was inoculated on the cheek of nude mice to establish a nude mice model of OSCC. After 3 weeks, mice were divided into 5 groups (4 experimental groups and 1 control group), with 15 in each group. L-OHP (17 mg x kg(-1)) was injected intravenously at 4 different time points during a period of 24 h, including 4 hours after lights on JHALO), 10 HALO, 16 HALO and 22 HALO for 4 experimental groups. The control group received normal saline of the same volume as that of L-OHP. The efficacy (tumor inhibition rate and survival time) and adverse reaction (body weight, white blood cell and perianal swelling) were observed after administration. The circadian rhythms of the efficacy and adverse reaction were examined by cosine analysis. RESULTS: L-OHP injected at 4, 16 and 22 HALO had great tumor inhibition rates, however, only 16 and 22 HALO groups significantly prolonged survival time of mice. The adverse reactions at 4 and 10 HALO were significantly severer than that of 16 and 22 HALO. Cosine analysis showed survival time, body weight and white blood cell counts had significant circadian rhythms. Mice received L-OHP at 14.88 HALO had the longest survival time. CONCLUSION: The time factor should be considered in L-OHP chronchemotherapy of patients with OSCC in order to increase the efficacy, decrease the adverse reaction of the drug and to improve the life quality of patients with OSCC.

Aberrant expression of clock gene period1 and its correlations with the growth, proliferation and metastasis of buccal squamous cell carcinoma.

Period1 (PER1) is an important core clock gene, which regulates normal cell proliferations and physiological rhythms of human beings. Recent studies have showed aberrant expressions and altered rhythms of PER1 were highly correlated to the carcinogenesis and development of malignant tumors. However, there is no study on the correlation of aberrant expressions and altered rhythms of PER1 with the growth, proliferation and metastasis of buccal squamous cell carcinoma (BSCC). In this study, PER1 and MMP-2 expression in the cancerous and adjacent noncancerous tissues of 38 patients with BSCC and its correlations with patients' clinical pathologic characteristics were investigated. A mouse model of BSCC was also established and mice were sacrificed at 4 different time points in a period of 24 hours. Xenografted tumor weight, proliferation index (PI), and mitotic index (MI) of tumors in the 4 time groups were detected. Results showed that PER1 expression was significantly down-regulated in cancerous tissues of patients with BSCC (P<0.05). PER1 expression was significantly down-regulated in patients of T3∼T4 staging and those with lymph node metastasis compared to that of T1∼T2 staging and those without lymph node metastasis (P<0.05), respectively. PER1 mRNA expression, MI and tumor weight had significant differences among the 4 time groups, which PI all confirmed to circadian rhythms. MI, PI, MMP-2 mRNA and tumor weight had negative correlation with PER1 mRNA expression. Peak value of PER1 mRNA expression and trough values of MI, PI and tumor weight all appeared in middle activity phase, whereas trough value of PER1 mRNA expression and peak values of MI, PI and tumor weight all occurred in middle rest phase. Our study suggested that aberrant expression of PER1 had significant correlation with the growth, proliferation and metastasis of BSCC and it might act as an anti-oncogene.

Circadian rhythm characteristics of oral squamous cell carcinoma growth in an orthotopic xenograft model.

BACKGROUND: Recent studies show that circadian rhythm changes are closely related to the occurrence and development of various tumors, such as breast, liver, and prostate. However, there are significant differences in circadian rhythm between different tumors. At present, the circadian rhythm characteristics of oral cancer remain unknown. The purpose of this study is to investigate the circadian rhythm characteristics of the in vivo growth of oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: Thirty-two nude mice were placed under 12-hour light/12-hour dark cycles. The human OSCC cell line BcaCD885 was inoculated in the cheek of nude mice. After 3 weeks, eight mice were sacrificed at four time points, including 4 hours after light onset (HALO), 10 HALO, 16 HALO, and 22 HALO, during a period of 24 hours. The volume of excised tumors was measured and the proliferative index (PI) and apoptotic index (AI) of tumor cells were determined by flow cytometry. A cosine analysis method was used to determine whether the tumor volume, PI, and AI obeyed a circadian rhythm. RESULTS: There was a significant circadian rhythm in the tumor volume and PI of OSCC cells. For the tumor volume, there were significant differences between the four time points. The peak and trough values of the tumor volume appeared at 3.23 HALO and 15.23 HALO, whereas the peak and trough values of PI appeared at 6.60 HALO and 18.16 HALO, respectively. However, there was no circadian rhythm in the AI of tumor cells, despite significant differences between the four time points. CONCLUSION: This study demonstrates, for the first time, that the tumor volume and PI of in vivo growing OSCC undergo circadian rhythms. These results support the assertion that time factor should be considered in the occurrence, development, treatment, efficacy evaluation and pathophysiology of OSCC.

Abnormal expression of PER1 circadian-clock gene in oral squamous cell carcinoma.

BACKGROUND: The PER1 circadian-clock gene plays an important role in the regulation of many normal physiological rhythms in vivo. It has been revealed recently that abnormal expression of PER1 correlates closely with the occurrence and development of many cancers. However, the expression and significance of PER1 in oral squamous cell carcinoma (OSCC) remains unknown. The purpose of the present study was to investigate the direct links between aberrant PER1 expression and clinicopathological features of OSCC. METHODS: PER1 expression in cancerous and adjacent noncancerous tissues from 41 patients with OSCC was detected by immunohistochemical staining and real-time reverse transcriptase polymerase chain reaction, and correlations were sought with clinicopathological features in patients. RESULTS: Expression of PER1 mRNA and protein in OSCC was significantly reduced compared with that in adjacent noncancerous tissue (P < 0.05). Expression of PER1 protein in oral phase III-IV SCC specimens was significantly lower than that in phase I-II specimens (P < 0.05), and stage T(1)-T(2) patients expressed significantly higher levels of PER1 protein than T(3)-T(4) patients (P < 0.05). Expression of PER1 in patients without lymph node metastasis was significantly higher than that in those with lymph node metastasis (P < 0.05). PER1 protein expression showed no significant correlation with patient gender and age, or with degree of tumor cell differentiation (P > 0.05). CONCLUSION: Changes in PER1 expression may play an important role in the development, invasion, and metastasis of OSCC, and may also provide novel ideas and methods for investigation of the occurrence, development, and targeted treatment OSCC.