Post-processing of a 3D-printed denture base polymer: Impact of a centrifugation method on the surface characteristics, flexural properties, and cytotoxicity.

OBJECTIVES: To investigate the impact of a centrifugation method on the surface characteristics, flexural properties, and cytotoxicity of an additively manufactured denture base polymer. METHODS: The tested specimens were prepared by digital light processing (DLP). A centrifugation method (CENT) was used to remove the residual uncured resin. In addition, the specimens were post-processed with different post-rinsing solutions: isopropanol (IPA), ethanol (EtOH), and tripropylene glycol monomethyl ether (TPM), respectively. A commercial heat-polymerized polymethyl methacrylate was used as a reference (REF). First, the values of surface topography, arithmetical mean height (Sa), and root mean square height (Sq) were measured. Next, flexural strength (FS) and modulus were evaluated. Finally, cytotoxicity was assessed using an extract test. The data were statistically analyzed using a one-way analysis of variance, followed by Tukey's multiple comparison test for post-hoc analysis. RESULTS: The Sa value in the CENT group was lower than in the IPA, EtOH, TPM, and REF groups (p < 0.001). Moreover, the CENT group had lower Sq values than other groups (p < 0.001). The centrifugation method showed a higher FS value (80.92 ± 8.65 MPa) than the EtOH (61.71 ± 12.25 MPa, p < 0.001) and TPM (67.01 ± 9.751 MPa, p = 0.027), while affecting IPA (72.26 ± 8.80 MPa, p = 0.268) and REF (71.39 ± 10.44 MPa, p = 0.231). Also, the centrifugation method showed no evident cytotoxic effects. CONCLUSIONS: The surfaces treated with a centrifugation method were relatively smooth. Simultaneously, the flexural strength of denture base polymers was enhanced through centrifugation. Finally, no evident cytotoxic effects could be observed from different post-processing procedures. CLINICAL SIGNIFICANCE: The centrifugation method could optimize surface quality and flexural strength of DLP-printed denture base polymers without compromising cytocompatibility, offering an alternative to conventional rinsing post-processing.

Trephination-based autonomous robotic surgery for dental implant placement: A proof of concept.

OBJECTIVES: To present a novel drilling protocol of trephine osteotomy technique for autologous bone grafting with simultaneous implant placement using an autonomous robotic system. METHODS: The novel protocol consists of 1) preoperative procedures: marker fabrication and fixation, data acquisition, and preoperative planning; 2) intraoperative procedures: registration and calibration, and osteotomy and implant placement performed by an autonomous dental implant robot; 3) postoperative procedures: CBCT acquisition and accuracy assessment. RESULT: The protocol was an effective method for implant osteotomy, with no reported intraoperative complications. The implant surgery was successfully completed, and autogenous bone was obtained. Meanwhile, the accuracy of implant placement was clinically acceptable, with minor deviations. CONCLUSIONS: Trephination-based robotic surgery can be successfully implemented in implant osteotomy, which might replace freehand implant surgery and conventional drilling protocol. However, further clinical studies are necessary. CLINICAL SIGNIFICANCE: The main finding of this case is a potential alternative for preserving autogenous bone during implant surgery.

The quality of life after keratinized mucosa augmentation around dental implants using xenogenic collagen matrix with or without stent.

BACKGROUND: The substitution of missing teeth with implants is a dependable and anticipated therapeutic approach. Despite numerous studies affirming long-term success rates, there exists a spectrum of potential biological and aesthetic complications. OBJECTIVE: The primary objective of this study was to assess patient responses subsequent to surgical interventions, with a specific emphasis on the utilization of xenogenic collagen matrix (XCM), both with and without the application of a stent secured over healing abutments, in the context of keratinized gingival mucosa augmentation. The principal aim was to evaluate and draw comparisons between the clinical outcomes resulting from these two procedural approaches, with a particular focus on critical parameters encompassing post-operative complications, patient comfort, and the overall efficacy in achieving successful keratinized tissue augmentation. methods: Sixty patients were selected for this study. The patients were divided into three groups: A, B, and a control group, with each group comprising 20 participants. We used XCM in experimental group A, XCM covered with surgical stent in experimental group B, and free gingival graft (FGG) in the control group. After the surgical procedure, patients were required to complete a visual analogue scale (VAS) questionnaire for post-operative complications, and a quality of life (QOL) questionnaire on days 1, 3, and 7. RESULTS: Patients in the experimental groups A and B demonstrated markedly improved outcomes when compared with the control group. Assessments conducted on days 1, 3, and 7 demonstrated diminished levels of pain, bleeding, and swelling in both experimental groups, with experimental group B showing the least discomfort. The incorporation of XCM, either with or without stents, was associated with a reduction in analgesic consumption, underscoring its favorable influence on post-operative comfort, notwithstanding the exception of halitosis in experimental group B. CONCLUSION: Using XCM with or without a stent for keratinized tissue augmentation has better post-operative outcomes associated with reduced swelling, bleeding, and pain based on the QOL survey. This study provides data to support the clinical application of XCM and stents.

Functional Biomaterials and Digital Technologies in Dentistry: From Bench to Bedside.

This Special Issue, "Functional Biomaterials and Digital Technologies in Dentistry: From Bench to Bedside", highlights the integration of advanced materials science and digital technologies in dental and maxillofacial applications [...].

Differences in resting-state brain activity in first-episode drug-naïve major depressive disorder patients with and without suicidal ideation.

Despite altered brain activities being associated with suicidal ideation (SI), the neural correlates of SI in major depressive disorder (MDD) have remained elusive. We enrolled 82 first-episode drug-naïve MDD patients including 41 with SI and 41 without SI, as well as 41 healthy controls (HCs). Resting-state functional and structural MRI data were collected. The measures of fractional amplitude of low-frequency fluctuation (fALFF) and grey matter volume (GMV) were calculated and compared. Compared with HCs, patients with SI exhibited increased fALFF values in the right rectus gyrus and left medial superior frontal gyrus, middle frontal gyrus and precuneus. Decreased GMV in the right parahippocampal gyrus, insula and middle occipital gyrus and increased GMV in the left superior frontal gyrus were detected in patients with SI. In addition, patients without SI demonstrated increased fALFF values in the right superior frontal gyrus and decreased fALFF values in the right postcentral gyrus. Decreased GMV in the left superior frontal gyrus, right medial superior frontal gyrus, opercular part of inferior frontal gyrus, postcentral gyrus, fusiform gyrus and increased left supplementary motor area, superior occipital gyrus, right anterior cingulate gyrus and superior temporal gyrus were revealed in patients with SI. Moreover, in comparison with patients without SI, increased fALFF values were identified in the left precuneus of patients with SI. However, no significant differences were found in GMV between patients with and without SI. These findings might be helpful for finding neuroimaging markers predicting individual suicide risk and detecting targeted brain regions for effective early interventions.

Effect of post-curing conditions on surface characteristics, physico-mechanical properties, and cytotoxicity of a 3D-printed denture base polymer.

OBJECTIVE: This study aims to investigate the influence of post-polymerization (post-curing) conditions on surface characteristics, flexural properties, water sorption and solubility, and cytotoxicity of additively manufactured denture base materials. METHODS: The tested specimens were additively manufactured using digital light processing and classified into different post-curing condition groups: submerged in water (WAT), submerged in glycerin (GLY), and air exposure (AIR). An uncured specimen (UNC) was used as a control. The surface topography and roughness were observed. The flexural strength and modulus were determined via a three-point bending test. The water sorption and solubility were subsequently tested. Finally, an extract test was performed to assess cytotoxicity. RESULTS: Different post-curing conditions had no significant effects on the surface topography and roughness (Sa value). Various post-curing conditions also had no significant effects on the flexural strength. Notably, the flexural modulus of the WAT group (2671.80 ± 139.42 MPa) was significantly higher than the AIR group (2197.47 ± 197.93 MPa, p = 0.0103). After different post-curing conditions, the water sorption and solubility of the specimens met the ISO standards. Finally, all post-curing conditions effectively reduced cytotoxic effects. SIGNIFICANCES: Post-curing with different oxygen levels improved flexural properties, and flexural modulus significantly increased after the specimens were submerged in water. In addition, water sorption and solubility, and cytocompatibility were optimized by post-curing, irrespective of the post-curing conditions. Therefore, the water-submerged conditions optimized the flexural modulus of the 3D-printed denture base materials.

Predictive factors for the treatment success of peri-implantitis: a protocol for a prospective cohort study.

INTRODUCTION: Peri-implantitis, a common biological complication of dental implant, has attracted considerable attention due to its increasing prevalence and limited treatment efficacy. Previous studies have reported several risk factors associated with the onset of peri-implantitis (eg, history of periodontitis, poor plaque control and smoking). However, inadequate data are available on the association between these risk factors and successful outcome after peri-implantitis therapy. This prospective cohort study aims to identify the local and systemic predictive factors for the treatment success of peri-implantitis. METHODS AND ANALYSIS: A single-centre cohort study will be conducted by recruiting 275 patients diagnosed with peri-implantitis. Sociodemographic variables, healthy lifestyles and systemic disorders will be obtained using questionnaires. In addition, clinical and radiographic examinations will be conducted at baseline and follow-up visits. Treatment success is defined as no bleeding on probing on more than one point, no suppuration, no further marginal bone loss (≥0.5 mm) and probing pocket depth ≤5 mm at the 12-month follow-up interval. After adjustment for age, sex and socioeconomic status, potential prognostic factors related to treatment success will be identified using multivariable logistic regression models. ETHICS AND DISSEMINATION: This cohort study in its current version (2.0, 15 July 2022) is in accordance with the Declaration of Helsinki and was approved by the Ethics Committee of Stomatological Hospital, Southern Medical University (EC-CT-(2022)34). The publication will be on behalf of the study site. TRIAL REGISTRATION NUMBER: ChiCTR2200066262.

Sex differences in the association between dual-energy x-ray absorptiometry-measured body composition and periodontitis.

BACKGROUND: A positive association between obesity based on body mass index (BMI) and periodontitis has been reported. Fat tissue-related systemic inflammation acts as the link to periodontal comorbidities of obesity. However, the BMI is unable to distinguish fat and fat-free tissues. More precise measures are required to evaluate body composition, including fat and fat-free tissues. This study aimed to determine the sex differences in the association between dual-energy x-ray absorptiometry (DXA)-measured body composition (i.e., fat mass and muscle mass) and phenotypes with periodontitis. METHODS: Cross-sectional data of 3892 participants from the National Health and Nutrition Examination Survey (NHANES) study 2011‒2014 were analyzed. Adiposity indices (fat mass index [FMI] and percentage body fat [%BF]) and muscle mass index (MMI) were calculated. The participants were categorized by the quintiles of FMI, MMI, and %BF. Body composition phenotypes were categorized as: low adiposity-low muscle (LA-LM), low adiposity-high muscle (LA-HM), high adiposity-low muscle (HA-LM), or high adiposity-high muscle (HA-HM), respectively. Periodontitis was defined by the CDC/AAP (Centers for Disease Control and Prevention/American Academy of Periodontology) criteria. Multivariable logistic regression analysis was conducted, stratified by sex. We further adjusted for white blood cell (WBC) counts in the sensitivity analysis. RESULTS: Restricted cubic splines revealed non-linear associations between body composition indices and periodontitis risk. Women with a higher FMI (odds ratio for Q5 vs. Q1 [ORQ5vs1] = 1.787, 95% confidence interval: 1.209-2.640) or %BF (ORQ5vs1 = 2.221, 1.509-3.268) had increased odds of periodontitis. In addition, women with HA-LM phenotype were more likely to develop periodontitis (OR = 1.528, 1.037-2.252). Interestingly, the WBC count, a systemic inflammatory biomarker, attenuated these associations. No statistically significant associations were found in men. CONCLUSIONS: The association between DXA-measured body composition and phenotypes with periodontitis differs per sex. Only in women higher adiposity indices and HA-LM phenotype were associated with an increased risk of periodontitis.

Accuracy of digital guided implant surgery: expert consensus on nonsurgical factors and their treatments / 口腔疾病防治

@#The standardized workflow of computer-aided static guided implant surgery includes preoperative examination, data acquisition, guide design, guide fabrication and surgery. Errors may occur at each step, leading to irreversible cumulative effects and thus impacting the accuracy of implant placement. However, clinicians tend to focus on factors causing errors in surgical operations, ignoring the possibility of irreversible errors in nonstandard guided surgery. Based on the clinical practice of domestic experts and research progress at home and abroad, this paper summarizes the sources of errors in guided implant surgery from the perspectives of preoperative inspection, data collection, guide designing and manufacturing and describes strategies to resolve errors so as to gain expert consensus. Consensus recommendation: 1. Preoperative considerations: the appropriate implant guide type should be selected according to the patient's oral condition before surgery, and a retaining screw-assisted support guide should be selected if necessary. 2. Data acquisition should be standardized as much as possible, including beam CT and extraoral scanning. CBCT performed with the patient’s head fixed and with a small field of view is recommended. For patients with metal prostheses inside the mouth, a registration marker guide should be used, and the ambient temperature and light of the external oral scanner should be reasonably controlled. 3. Optimization of computer-aided design: it is recommended to select a handle-guided planting system and a closed metal sleeve and to register images by overlapping markers. Properly designing the retaining screws, extending the support structure of the guide plate and increasing the length of the guide section are methods to feasibly reduce the incidence of surgical errors. 4. Improving computer-aided production: it is also crucial to set the best printing parameters according to different printing technologies and to choose the most appropriate postprocessing procedures.

Mediating role of systemic inflammation in the association between heavy metals exposure and periodontitis risk.

BACKGROUND: This study evaluated the mediating role of systemic inflammation in the association between exposure to heavy metals and periodontitis in a nationwide sample of adults. METHODS: Pooled cross-sectional data from the National Health and Nutrition Examination Survey (NHANES 2009-2014) were used (n = 8993). Periodontitis was defined by a full-mouth examination and classified as no/mild and moderate/severe (mod/sev) groups. Blood and urinary heavy metal levels were investigated, including cadmium (Cd), lead (Pb), and mercury (Hg). In addition, systemic inflammation was assessed using circulatory leukocyte counts and C-reactive protein (CRP) levels. RESULTS: Multivariable logistic regression analysis revealed the positive associations of blood and urinary levels of Cd and Pb with mod/sev periodontitis. In contrast,blood Hg levels did not show a significant association. The odds of having periodontitis were 1.233 and 1.311 times higher for each one-unit increment in Ln-transformed blood Cd (95% confidence interval [CI]: 1.109-1.371) and Pb (95% CI: 1.170-1.470), respectively. Mediation analysis suggested a 6.3% to 11.5% contribution of leucocyte counts in the association of blood Cd and Pb levels with periodontitis. Sensitivity analyses for urinary Cd levels yielded consistent mediating effects. However, no significant mediating effect of CRP was detected. CONCLUSION: Higher exposures to Cd and Pb were positively associated with periodontitis risk. These associations might be partially mediated by the elevated levels of leukocytes rather than CRP. Further longitudinal studies are needed to elucidate the discordant results of the systemic inflammatory biomarkers.

Accuracy of autonomous robotic surgery for dental implant placement in fully edentulous patients: A retrospective case series study.

OBJECTIVES: This study evaluated the accuracy of dental implant placement using the robotic computer-assisted implant surgery (r-CAIS) technology in fully edentulous patients. MATERIALS AND METHODS: Fully edentulous and terminal dentition patients were enrolled for r-CAIS technology. Based on the cone-beam computed tomography (CBCT) examination, a customized positioning marker and a preoperative surgical plan were created before surgery. During the implant surgery, the implant osteotomy and placement were automatically performed using an autonomous robotic surgery system under the surgeon's supervision. A postoperative CBCT scan was used to determine the discrepancies between the planned and placed implants. RESULTS: Ten patients with 59 implants underwent autonomous robotic surgery. No adverse surgical events occurred. The deviations of global coronal, global apical, and angular were 0.67 ± 0.37 mm (95% CI: 0.58-0.77 mm), 0.69 ± 0.37 mm (95% CI: 0.59-0.78 mm), and 1.27° ± 0.59° (95% CI: 1.42°-1.11°), respectively. CONCLUSIONS: The autonomous r-CAIS technology proved an accurate surgical approach for implant placement in fully edentulous patients due to the control of the angular deviation. Autonomous robotic surgery seems promising as an accurate technology for treating fully edentulous patients. However, further trials are required to provide more hard clinical evidence.

Serum Anti-Aging Protein α-Klotho Mediates the Association between Diet Quality and Kidney Function.

Adherence to healthy dietary patterns is associated with a reduced risk of kidney dysfunction. Nevertheless, the age-related mechanisms that underpin the relationship between diet and kidney function remain undetermined. This study aimed to investigate the mediating role of serum α-Klotho, an anti-aging protein, in the link between a healthy diet and kidney function. A cross-sectional study was conducted on a cohort of 12,817 individuals aged between 40 and 79 years who participated in the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2016. For each participant, the Healthy Eating Index 2015 (HEI-2015) score was calculated as a measure of a healthy dietary pattern. Creatinine-based estimated glomerular filtration rate (eGFR) was used to assess kidney function. Multivariable regression models were used to analyze the association between the standardized HEI-2015 score and eGFR after adjusting for potential confounders. Causal mediation analysis was performed to assess whether serum α-Klotho influenced this association. The mean (±SD) eGFR of all individuals was 86.8 ± 19.8 mL/min per 1.73 m2. A high standardized HEI-2015 score was associated with a high eGFR (ß [95% CI], 0.94 [0.64-1.23]; p < 0.001). The mediation analysis revealed that serum α-Klotho accounted for 5.6-10.5% of the association of standardized overall HEI-2015 score, total fruits, whole fruits, greens and beans, and whole grain with eGFR in the NHANES. According to the results from the subgroup analysis, serum α-Klotho exerted a mediating effect in the participants aged 60-79 years and in males. A healthy diet may promote kidney function by up-regulating serum anti-aging α-Klotho. This novel pathway suggests important implications for dietary recommendations and kidney health.

Development of a model for radionuclide transport in streams for biosphere assessment purpose.

As a part of the overall safety assessment for a geological disposal of radioactive waste, models for different ecosystems are used to evaluate doses to humans and biota from possible radionuclide discharges to the biosphere. In previous safety assessments, transport modelling of radionuclides in running waters such as streams has been much simplified to the extent that only dilution of the inflow of radionuclides has been considered with no regard of any other interactions. Hyporheic exchange flow (HEF) is the flow of surface water in streams that enters the subsurface zone and, after some time, returns to the surface. HEF has been studied for decades. Hyporheic exchange and the residence time in the hyporheic zone are key parameters controlling the transport of radionuclides in a stream. Furthermore, recent studies have shown that HEF can reduce the groundwater upwelling area and increase the upwelling velocity in areas closest to the streambed water interface. In this paper, the development of an assessment model describing radionuclide transport with consideration of HEF and deep groundwater upwelling along streams is presented. An approach to parameterising the hyporheic exchange processes into an assessment model is based on a comprehensive study that has been performed in five different Swedish catchments. Sensitivity analyses are performed to explore the effect with consideration of the inflow of radionuclides with regard to HEF and deep groundwater upwelling in a safety assessment perspective. Finally, we include some suggestions for the application of the assessment model to long-term radiological safety assessments.

One-Abutment at One-Time in Posterior Edentulism: A Systematic Review and Meta-Analysis.

OBJECTIVE: The objective of this systematic review and meta-analysis was to investigate the clinical significance of one-abutment at one-time protocol in healed posterior edentulism. METHODS: An online search was undertaken in November 2022, which included PubMed, Cochrane Library, Wiley Online Library, and Google Scholar in addition to manual searching. The Cochrane Collaboration tool was performed to assess the quality of selected articles. Marginal bone loss (MBL) was estimated by the performance of meta-analysis. Moreover, all the pooled analyses were based on random-effect models. Subgroup analysis was applied to evaluate the effects of different variables. RESULTS: In line with the inclusion criteria, 6 trials with 446 dental implants were identified. The meta-analysis showed a total of 0.22 mm less MBL within 6 months and decreased by 0.30 mm at 1-year follow-up in favor of one-abutment at one-time protocol. A significant loss MBL was found in implants placed equicrestally using one-abutment at one-time protocol [6 months: mean difference (MD): -0.22 mm; 95% CI, -0.34 to 0.10 mm, P =0.0004; 12 months: MD: -0.32 mm; 95% CI, -0.40 to -0.24 mm, P <0.00001), whereas no difference was found between 2 groups in an implant placed subscrestally (6 months: MD: 0.14 mm; 95% CI, -0.03 to 0.22 mm; P =0.11; 12 months: MD: -0.12 mm; 95% CI, -0.32 to 0.08 mm; P =0.23). CONCLUSIONS: Implant platform position might greatly affect the marginal bone level. Moreover, one-abutment at one-time protocol demonstrated better bone preservation in implants placed equicrestally in healed posterior edentulism. CLINICAL RELEVANCE: This study highlights the significant clinical application of one-abutment at one-time protocol in healed posterior edentulism.

Cytotoxicity of Biodegradable Zinc and Its Alloys: A Systematic Review.

Zinc-based biodegradable metals (BMs) have been developed for biomedical implant materials. However, the cytotoxicity of Zn and its alloys has caused controversy. This work aims to investigate whether Zn and its alloys possess cytotoxic effects and the corresponding influence factors. According to the guidelines of the PRISMA statement, an electronic combined hand search was conducted to retrieve articles published in PubMed, Web of Science, and Scopus (2013.1-2023.2) following the PICOS strategy. Eighty-six eligible articles were included. The quality of the included toxicity studies was assessed utilizing the ToxRTool. Among the included articles, extract tests were performed in 83 studies, and direct contact tests were conducted in 18 studies. According to the results of this review, the cytotoxicity of Zn-based BMs is mainly determined by three factors, namely, Zn-based materials, tested cells, and test system. Notably, Zn and its alloys did not exhibit cytotoxic effects under certain test conditions, but significant heterogeneity existed in the implementation of the cytotoxicity evaluation. Furthermore, there is currently a relatively lower quality of current cytotoxicity evaluation in Zn-based BMs owing to the adoption of nonuniform standards. Establishing a standardized in vitro toxicity assessment system for Zn-based BMs is required for future investigations.

Automatic segmentation of inferior alveolar canal with ambiguity classification in panoramic images using deep learning.

Background: Manual segmentation of the inferior alveolar canal (IAC) in panoramic images requires considerable time and labor even for dental experts having extensive experience. The objective of this study was to evaluate the performance of automatic segmentation of IAC with ambiguity classification in panoramic images using a deep learning method. Methods: Among 1366 panoramic images, 1000 were selected as the training dataset and the remaining 336 were assigned to the testing dataset. The radiologists divided the testing dataset into four groups according to the quality of the visible segments of IAC. The segmentation time, dice similarity coefficient (DSC), precision, and recall rate were calculated to evaluate the efficiency and segmentation performance of deep learning-based automatic segmentation. Results: Automatic segmentation achieved a DSC of 85.7% (95% confidence interval [CI] 75.4%-90.3%), precision of 84.1% (95% CI 78.4%-89.3%), and recall of 87.7% (95% CI 77.7%-93.4%). Compared with manual annotation (5.9s per image), automatic segmentation significantly increased the efficiency of IAC segmentation (33 ms per image). The DSC and precision values of group 4 (most visible) were significantly better than those of group 1 (least visible). The recall values of groups 3 and 4 were significantly better than those of group 1. Conclusions: The deep learning-based method achieved high performance for IAC segmentation in panoramic images under different visibilities and was positively correlated with IAC image clarity.

Association between the quality of plant-based diets and periodontitis in the U.S. general population.

AIM: To investigate the relationship between plant-based diet indices (PDIs) and periodontitis and serum IgG antibodies against periodontopathogens in the U.S. MATERIALS AND METHODS: We analysed cross-sectional data on 5651 participants ≥40 years of age from the Third National Health and Nutrition Examination Survey. Food frequency questionnaire data were used to calculate the overall PDI, healthy plant-based diet index (hPDI), and unhealthy plant-based diet index (uPDI). Periodontitis was defined using a half-reduced Centers for Disease Control and Prevention and American Academy of Periodontology case definition. Serum antibodies against 19 periodontopathogens were used to classify the population into two subgroups using hierarchical clustering. Survey-weighted multivariable logistic regressions were applied to assess the associations of PDI/hPDI/uPDI z-scores with periodontitis and hierarchical clusters after adjusting for potential confounders. RESULTS: A total of 2841 (50.3%) participants were defined as having moderate/severe periodontitis. The overall PDI z-score was not significantly associated with the clinical and bacterial markers of periodontitis. By considering the healthiness of plant foods, we observed an inverse association between hPDI z-score and periodontitis (odds ratio [OR] = 0.925, 95% confidence interval [CI]: 0.860-0.995). In contrast, higher uPDI z-score (adherence to unhealthful plant foods) might increase the risk of periodontitis (OR = 1.100; 95% CI: 1.043-1.161). Regarding antibodies against periodontopathogens, the participants in cluster 2 had higher periodontal antibodies than those in cluster 1. The hPDI z-score was positively associated with cluster 2 (OR = 1.192; 95% CI: 1.112-1.278). In contrast, an inverse association between uPDI z-score and cluster 2 was found (OR = 0.834; 95% CI: 0.775-0.896). CONCLUSIONS: Plant-based diets were associated with periodontitis, depending on their quality. A healthy plant-based diet was inversely related to an increased risk of periodontitis but positively related to elevated antibody levels against periodontopathogens. For an unhealthy plant-based diet, the opposite trends were observed.

Influence of additive manufacturing method and build angle on the accuracy of 3D-printed palatal plates.

OBJECTIVES: In this in vitro study, the effects of additive manufacturing (AM) methods and build angles on the trueness and precision of 3D-printed palatal plate orthodontic appliances for newborns and infants were examined. METHODS: Specimens were fabricated by different representative AM methods, including digital light processing (DLP), fused filament fabrication (FFF), and MultiJet printing (MJP). Three build angles (0°, 45°, and 90°) were used. After scanning, all specimens were analyzed using the 3D inspection software. The root mean square values were measured for trueness and precision. Color maps were created to detect deviations in samples. The data were statistically analyzed with a two-way ANOVA. RESULTS: The trueness and precision were statistically influenced by both AM methods and build angles (p < 0.05). Moreover, the root mean square values of the 45° DLP (0.0221 ± 0.0017 µm) and the 0° MJP (0.0217 ± 0.0014 µm) were significantly lower compared to those in other groups (p < 0.001). CONCLUSIONS: AM methods (DLP, FFF, and MJP) and build angles (0°, 45°, and 90°) significantly impacted the dimensional accuracy of additively manufactured palatal plate orthodontic appliances. Also, the 45° DLP and the 0° MJP were associated with the highest trueness and precision. CLINICAL SIGNIFICANCE: All tested AM methods with different build angles yielded clinically acceptable outcomes (within an acceptance range of ±300 µm for trueness), achieving the highest accuracy with a technology-specific suitable build angle.

Accuracy of autonomous robotic surgery for single-tooth implant placement: A case series.

OBJECTIVES: This study aimed to investigate the accuracy of the autonomous robotic computer-assisted implant surgery (r-CAIS) for single-tooth implant placement. METHODS: Patients with a single missing tooth were enrolled for the autonomous robotic implant surgery. The patients underwent a cone-beam computed tomography (CBCT) scan with a positioning marker. Virtual preoperative implant placement and a drilling plan were created before surgery. The robotic system automatically performed the implant osteotomy and placement intraoperatively under the surgeon's supervision. A postoperative CBCT scan was performed to evaluate the deviations between the planned and placed implants. RESULTS: Ten patients with single dental implant placement were enrolled. No adverse surgical events and postoperative complications (i.e., infection and early implant failure) were reported. The autonomous robotic implant surgery exhibited a mean overall coronal deviation of 0.74 mm (95% CI: 0.53 to 0.94 mm), a mean overall apical deviation of 0.73 mm (95% CI: 0.53 to 0.93 mm), and an angular deviation of 1.11° (95% CI: 0.78 to 1.44°), respectively. CONCLUSIONS: The high accuracy of autonomous r-CAIS technology in single-tooth implant placement was attributed to the control of the angular deviation and axial errors. CLINICAL SIGNIFICANCE: The main findings of this study provide significant evidence to support the autonomous robotic implant surgery system as a potential alternative in dental implant surgery.

Association of Dietary Patterns with Parkinson's Disease: A Cross-Sectional Study Based on the United States National Health and Nutritional Examination Survey Database.

INTRODUCTION: Although studies have explored some dietary patterns for Parkinson's disease (PD), more other dietary patterns and food item under the dietary pattern are needed to investigate. This study aimed to identify more categories of dietary patterns for PD and further explore the association of single food item with PD. METHODS: The 2015-2018 US National Health and Nutritional Examination Survey (NHANES) database was used for data extraction. The data on demographics and nutrient intake were collected. Dietary patterns were derived from food categories by factor analysis. The association between dietary patterns or single food item and PD was explored using logistic regression analysis in the overall and only in secure PD cases, and results were expressed as odds ratio (OR) with 95% confidence intervals (CIs). Sensitivity analysis was performed by excluding participants using unsecure PD medication. RESULTS: Among 5,824 participants aged over 50 years, 91 were diagnosed as PD. Factor analysis identified 5 major dietary pattern factors. We observed that the increased adherence to Mediterranean diet (MeDi) was associated with the reduced odds of PD (OR = 0.78, 95% CI: 0.65-0.93). The higher adherence to Western pattern was associated with the increased odds of PD (OR = 2.19, 95% CI: 1.16-4.14). In addition, high intake of sweets under Western pattern was found to be associated with the higher odds of PD (OR = 2.01, 95% CI: 1.08-3.71). CONCLUSIONS: The odds of PD decreased by higher MeDi adherence and increased by higher Western pattern adherence, especially sweets intake in this pattern, suggesting population ≥50 years should adhere to MeDi pattern and decrease the adherence to Western pattern, reducing the intake of sweets.