Protective effect of Cordycepin on blood-testis barrier against pre-puberty polystyrene nanoplastics exposure in male rats.

Plastic pollution is an emerging environmental issue, with microplastics and nanoplastics raising health concerns due to bioaccumulation. This work explored the impact of polystyrene nanoparticle (PS-NPs) exposure during prepuberty on male reproductive function post maturation in rats. Rats were gavaged with PS-NPs (80 nm) at 0, 3, 6, 12 mg/kg/day from postnatal day 21 to 95. PS-NPs accumulated in the testes and reduced sperm quality, serum reproductive hormones, and testicular coefficients. HE staining showed impaired spermatogenesis. PS-NPs disrupted the blood-testis barrier (BTB) by decreasing junction proteins, inducing inflammation and apoptosis. Transcriptomics identified differentially expressed genes related to metabolism, lysosome, apoptosis, and TLR4 signaling. Molecular docking revealed Cordycepin could compete with polystyrene for binding to TLR4. Cordycepin alleviated oxidative stress and improved barrier function in PS-NPs treated Sertoli cells. In conclusion, prepubertal PS-NPs exposure induces long-term reproductive toxicity in male rats, likely by disrupting spermatogenesis through oxidative stress and BTB damage. Cordycepin could potentially antagonize this effect by targeting TLR4 and warrants further study as a protective agent. This study elucidates the mechanisms underlying reproductive toxicity of PS-NPs and explores therapeutic strategies.

Therapeutic effectiveness of anlotinib combined with etoposide in extensive-stage small-cell lung cancer: a single-arm, phase II trial.

BACKGROUND: Anlotinib plus chemotherapy as first-line treatment for extensive-stage small-cell lung cancer (ES-SCLC) achieves good efficacy, but there is still room for improvement. This clinical study examined the effectiveness of anlotinib plus etoposide for maintenance therapy in ES-SCLC. METHODS: The current single-arm, prospective phase II study was performed at Jiangsu Cancer Hospital (March 2019 to March 2022). After successful primary etoposide-based therapy, anlotinib was administered at 12 mg/day on days 1 to 14 of 21-day cycles until disease progression or consent withdrawal. All patients also received etoposide at 50 mg/day on days 1 to 14 of 21-day cycles for a maximum of six cycles. Progression-free survival (PFS) constituted the primary study endpoint. Secondary endpoints were overall survival (OS), objective remission rate (ORR), disease control rate (DCR), and safety. In addition, adverse events (AEs) were assessed. RESULTS: Twenty-eight patients were treated. Median PFS and OS were 8.02 (95%CI 5.36-10.67) and 11.04 (95%CI 10.37-11.68) months, respectively. Totally 9 and 18 participants showed a partial response and stable disease, respectively; ORR and DCR were 32.14% and 96.43%, respectively. The commonest all-grade AEs were fatigue (n = 11, 39.28%), hypertension (n = 11, 39.28%), loss of appetite (n = 9, 32.14%), oral mucositis (n = 7, 25.00%) and proteinuria (n = 6, 21.40%). Grade 3-4 AEs included fatigue (n = 4, 14.28%), hypertension (n = 2, 7.14%), hand and foot syndrome (n = 2, 7.14%), oral mucositis (n = 1, 3.57%), hemoptysis (n = 1, 3.57%), proteinuria (n = 1, 3.57%), gingival bleeding (n = 1, 3.57%), and serum creatinine elevation (n = 1, 3.57%). CONCLUSION: Maintenance anlotinib plus etoposide achieves promising PFS and OS in clinical ES-SCLC. REGISTRATION NUMBER: ChiCTR1800019421.

Study of oral microorganisms contributing to non-carious cervical lesions via bacterial interaction and pH regulation.

There is a lack of evidence about the relationship between microorganisms and non-carious cervical lesions (NCCLs) due to limited technologies. A group of 78 patients was enrolled for microbial 16S rRNA sequencing of dental plaques on normal and defective cervical surfaces. Parallel data from 39 patients were analysed with paired t tests, and Fusobacteriales exhibited significantly less distribution on NCCLs than on normal surfaces. As a result, Fusobacterium nucleatum, the most common oral bacterial strain belonging to the order Fusobacteriales, was selected for further research. From a scanning electron microscopy (SEM) scan, the tooth surface with Fusobacterium nucleatum and Streptococcus mutans culture was more intact than that without Fusobacterium nucleatum. Furthermore, the calcium contents in groups with Fusobacterium nucleatum were significantly higher than that without it. In further mechanistic research, Fusobacterium nucleatum was demonstrated to adhere to and disturb other organisms as well as producing alkaline secretions to neutralize the deleterious acidic environment, protecting the tooth structure. In conclusion, microorganisms and NCCLs were confirmed directly related through adherent bacterial interactions and pH regulation. The research provides a new perspective and experimental evidence for the relation between microorganisms and NCCLs, which guides clinical treatment and preventive dentistry in the future.

The effect of anatomy on osteogenesis after maxillary sinus floor augmentation: a radiographic and histological analysis.

OBJECTIVES: To assess how anatomy and osteogenesis correlated with results of maxillary sinus floor augmentation (MSFA). MATERIALS AND METHODS: Patients with partial edentulism and advanced atrophy of the posterior maxillae (≤ 4 mm residual bone height, RBH) underwent MSFA with sole deproteinized bovine bone matrix (DBBM) through a lateral approach. After a 6 to 9-month healing period, bone core biopsies were obtained from the sites of implant insertion for histological evaluation. The correlations between anatomical and histomorphometric variables were analyzed in a multiple regression model. RESULTS: Forty-nine patients were recruited. One biopsy per patient was obtained from the augmented sinus. Thirty-seven bone core biopsies were intact and met the requirement for histomorphometry analysis. The mean (± standard deviation) percentages of vital bone (VB), remaining DBBM, and non-mineralized tissue were 18.25 ± 4.76%, 27.74 ± 6.68%, and 54.08 ± 6.07%, respectively. No statistically significant correlations were found between RBH and VB% (p = 0.44) or between sinus contour and VB% (p = 0.33). However, there was an inverse correlation between the sinus width (SW) and VB % (SW1: R2 = 0.13, p = 0.03; SW2: R2 = 0.15, p = 0.02). CONCLUSIONS: After a healing period of 6-9 months, wider sinuses augmented with DBBM alone tended to have a lower proportion of new bone formation, while RBH and sinus contour did not appear to affect osteogenesis after MSFA. CLINICAL RELEVANCE: This study emphasized the effect of anatomy on osteogenesis after MSFA. The result of the study may have an indication to the clinician that SW is a consideration when selecting the bone grafting material and deciding the healing period of MSFA.

Novel mutations identified in patients with tooth agenesis by whole-exome sequencing.

OBJECTIVES: To identify potentially pathogenic mutations for tooth agenesis by whole-exome sequencing. SUBJECTS AND METHODS: Ten Chinese families including five families with ectodermal dysplasia (syndromic tooth agenesis) and five families with selective tooth agenesis were included. Whole-exome sequencing was performed using genomic DNA. Potentially pathogenic mutations were identified after data filtering and screening. The pathogenicity of novel variants was investigated by segregation analysis, in silico analysis, and functional studies. RESULTS: One novel mutation (c.441_442insACTCT) and three reported mutations (c.252delT, c.463C>T, and c.1013C>T) in EDA were identified in families with ectodermal dysplasia. The novel EDA mutation was co-segregated with phenotype. A functional study revealed that NF-κB activation was compromised by the identified mutations. The secretion of active EDA was also compromised detection by western blotting. Novel Wnt10A mutations (c.521T>C and c.653T>G) and EVC2 mutation (c.1472C>T) were identified in families with selective tooth agenesis. The Wnt10A c.521T>C mutation and the EVC2 c.1472C>T mutation were considered as pathogenic for affecting highly conserved amino acids, co-segregated with phenotype and predicted to be disease-causing by SIFT and PolyPhen2. Moreover, several reported mutations in PAX9, Wnt10A, and FGFR3 were also detected. CONCLUSIONS: Our study expanded our knowledge on tooth agenesis spectrum by identifying novel variants.

Design Rules for Template-Confined DNA-Mediated Nanoparticle Assembly.

Template-based strategies are becoming increasingly important for controlling the position of nanoparticle-based (NP-based) structures on surfaces for a wide variety of encoding and device fabrication strategies. Thus, there is an increasing need to understand the behavior of NPs in confined spaces. Herein, a systematic investigation of the diffusion and adsorption properties of DNA-modified NPs is presented in lithographically defined, high-aspect-ratio pores using a template-confined, DNA-mediated assembly. Leveraging the sequence-specific binding affinity of DNA, it is discovered that although NP adsorption in deep polymer pores follows a traditional Langmuir adsorption model when under thermodynamic control, such NPs kinetically follow Fick's classical law of diffusion. Importantly, these observations allow one to establish design rules for template-confined, DNA-mediated NP assembly on substrates based on pore dimensions, NP size and shape, NP concentration, temperature, and time. As a proof-of-concept example, these design rules are used to engineer a vertical, four-layer assembly consisting of individual octahedral NPs stacked on top of one another, with in-plane positioning defined by pores generated by e-beam lithography.

Implant placement and loading protocols in partially edentulous patients: A systematic review.

OBJECTIVES: To systematically review the evidence for the clinical outcome of fixed implant prostheses treated with different combinations of implant placement and loading protocols in partially edentulous patients. MATERIALS AND METHODS: An electronic search was performed in Medline, Embase, and Central to identify studies investigating the outcome of implants subjected to immediate placement + immediate restoration/loading (Type 1A), immediate placement + early loading (Type 1B), immediate placement + conventional loading (Type 1C), early placement + immediate restoration/loading (Type 2-3A), early placement + early loading (Type 2-3B), early placement + conventional loading (Type 2-3C), late placement + immediate restoration/loading (Type 4A), late placement + early loading (Type 4B), late placement + conventional loading (Type 4C) with implant-supported fixed dental prostheses (IFDPs) in partially edentulous patients. Only human studies with at least 10 cases and a minimum follow-up time of 12 months, reporting on solid-screw-type implants with rough surfaces and an intra-osseous diameter between 3 and 6 mm, were included. A cumulative survival rate for each type of the implant placement and loading protocols was weighted by the duration of follow-up and number of implants. RESULTS: The search provided 5,248 titles from which 2,362 abstracts and 449 full-text articles were screened. A total of 69 publications that comprised 23 comparative studies (15 randomized controlled trials, 7 controlled clinical trials) and 47 noncomparative studies (34 prospective cohort studies, 13 retrospective cohort studies) were included for analysis. Considerable heterogeneity in study design was found, and therefore, a meta-analysis of controlled studies was not possible. The weighted cumulative survival rate of each type of placement and loading protocol was 98.4% (Type 1A), 98.2% (Type 1B), 96.0% (Type 1C), 100% (Type 2-3B), 96.3% (Type 2-3C), 97.9% (Type 4A), 98.3% (Type 4B), and 97.7% (Type 4C). Type 1C, Type 2-3C, Type 4B, and Type 4C were scientifically and clinically validated (SCV). Type 1A, Type 1B, and Type 4A were clinically documented (CD), and Type 2-3A and Type 2-3B were clinically insufficiently documented (CID). CONCLUSIONS: Evaluating outcomes in oral implantology by combining the placement and loading protocols are paramount. The selected loading protocol appears to influence the outcome of immediate implant placement.

Group 2 ITI Consensus Report: Prosthodontics and implant dentistry.

OBJECTIVES: Working Group 2 was convened to address topics relevant to prosthodontics and dental implants. Systematic reviews were developed according to focused questions addressing (a) the number of implants required to support fixed full-arch restorations, (b) the influence of intentionally tilted implants compared to axial positioned implants when supporting fixed dental prostheses (FDPs), (c) implant placement and loading protocols, (d) zirconia dental implants, (e) zirconia and metal ceramic implant supported single crowns and (f) zirconia and metal ceramic implant supported FDPs. MATERIALS AND METHODS: Group 2 considered and discussed information gathered in six systematic reviews. Group participants discussed statements developed by the authors and developed consensus. The group developed and found consensus for clinical recommendations based on both the statements and the experience of the group. The consensus statements and clinical recommendations were presented to the plenary (gathering of all conference attendees) and discussed. Final versions were developed after consensus was reached. RESULTS: A total of 27 consensus statements were developed from the systematic reviews. Additionally, the group developed 24 clinical recommendations based on the combined expertise of the participants and the developed consensus statements. CONCLUSIONS: The literature supports the use of various implant numbers to support full-arch fixed prostheses. The use of intentionally tilted dental implants is indicated when appropriate conditions exist. Implant placement and loading protocols should be considered together when planning and treating patients. One-piece zirconia dental implants can be recommended when appropriate clinical conditions exist although two-piece zirconia implants should be used with caution as a result of insufficient data. Clinical performance of zirconia and metal ceramic single implant supported crowns is similar and each demonstrates significant, though different, complications. Zirconia ceramic FDPs are less reliable than metal ceramic. Implant supported monolithic zirconia prostheses may be a future option with more supporting evidence.

Primary implant stability based on alternative site preparation techniques: A systematic review and meta-analysis.

AIM: To evaluate the effect of special implant site preparation methods in improving primary implant stability in low-density bone. MATERIAL AND METHODS: This meta-analysis included studies published in English and Mandarin Chinese up to March 31, 2022 from MEDLINE/PubMed, Embase, Scopus, and Wanfang databases. The primary stability of five site preparation methods were measured using implant stability quotient. The random-effects model was chosen for data analysis. Grading of recommendations assessment, development, and evaluation assessment was adopted as a collective grading of the overall body of evidence. RESULTS: 12 of the 17 studies included in the meta-analysis were randomized control trials. Three studies investigated osseodensification drilling (OD), eight studies examined osteotome technique (OT), five studies explored piezosurgery (PS), and four studies were conducted on under-drilling (UD). Meta-analysis showed a statistically significant increase in primary stability for the OD (mean difference [MD], 10.25; 95% CI: 4.97-15.52; p < 0.001), OT (MD, 6.34; 95% CI: 2.26-10.42; p = 0.002), and UD (MD, 11.43; 95% CI: 5.17-17.68; p < 0.001) groups when compared to the conventional drilling group, while the PS group did not (MD, 1.50; 95% CI: -2.54-5.54; p = 0.47). CONCLUSION: Significantly higher primary implant stability was shown in the OD, UD, and OT groups compared to the conventional drilling group. PS displayed the least favorable primary stability and when compared to conventional drilling, was not statistically significant.

Clinical Outcomes of Immediate Implant Loading with Fixed Prostheses in Edentulous Maxillae: A Systematic Review.

PURPOSE: To review the evidence from the clinical outcomes of immediately loaded implants with fixed prostheses in edentulous maxillae. MATERIALS AND METHODS: An electronic search was performed in PubMed/MEDLINE, Embase, and Cochrane to identify studies investigating the outcome of implants subjected to immediate loading with fixed dental prostheses in edentulous maxillae. Only clinical studies with more than 10 patients and a mean follow-up time of more than 12 months were included. Meta-analysis was utilized to compare the clinical outcomes between immediately loaded implants and conventionally loaded implants. For immediately loaded implants, a cumulative implant survival rate (ISR) was weighted by the duration of follow-up and number of implants. The weighted marginal bone loss (MBL) was also assessed. RESULTS: A total of 33 studies (16 retrospective studies and 17 prospective studies) were included, which involved 2,635 patients and 12,480 implants. Meta-analysis did not reveal a significant difference of ISR or MBL between the two loading groups. For immediately loaded implants, the weighted cumulative ISR was 95.53% (median: 97.50%) with a mean follow-up of 46.07 months (SD: 30.92). Fourteen studies reported on the MBL of implants, and the mean MBL was 1.19 mm (SD: 0.88) with a mean period of 57.70 months (SD: 32.56). The results should be interpreted with caution due to the lack of randomized controlled trials (RCTs) and the heterogeneity of the data. CONCLUSION: Despite the lack of RCTs, immediate implant loading with a fixed prosthesis in the edentulous maxilla seems to be a reliable treatment alternative with a high ISR, when appropriate inclusion/exclusion criteria are followed.

Implant-supported provisional prosthesis facilitated the minor revision of occlusion and incisor exposure after orthognathic surgery of extended oligodontia in maxilla.

BACKGROUND: The congenital oligodontia in maxilla could result in a significant skeletal jaw malformation such as atrophic maxilla and severe skeletal class III malocclusion. Since there is no referable dentition in anterior maxilla, the orthognathic surgery and oral rehabilitation for those patients becomes more challenging and less predictable. MATERIALS AND METHODS: We hereby present a new sequencing of interdisciplinary treatments, including calvarial bone grafting, installation of implant-supported provisional prosthesis, bimaxillary orthognathic surgery, and the final installation of dental implants and the fixed prosthesis. RESULTS: The facial esthetics and function of the permanent prosthesis were satisfactory, with a remarkable improvement in the maxillomandibular relation, adequate horizontal and vertical repositioning of the maxilla, and appropriate incisor exposure. CONCLUSION: Although more surgeries and longer treatment period may be required due to the interdisciplinary treatment plan, better aesthetic and functional outcomes may be acquired by this reported procedure in the long-term for young patients.

Placement and Loading Protocols for Single Implants in Different Locations: A Systematic Review.

PURPOSE: To analyze the effect of implant placement and loading protocols (protocol types) on the survival of single implant tooth replacements in different locations. MATERIALS AND METHODS: An electronic search was conducted to identify clinical trials regarding outcomes of single implants subjected to different treatment protocols. A weighted mean survival rate for each protocol type in the anterior maxilla, anterior mandible, posterior maxilla, and posterior mandible was calculated. Study design, sample size, and outcome homogeneity were used to evaluate the validation of each protocol type in different locations. RESULTS: A total of 45 publications (13 RCTs, 21 prospective studies, and 11 retrospective studies) were included. The anterior maxilla was the most reported site (35 studies, 1,391 implants, weighted survival rate: 97.5% to 99.6%). Immediate placement + conventional loading (Type 1C) and late placement + immediate restoration/loading (Type 4A) were scientifically and clinically validated (SCV). For the posterior maxilla (19 studies, 567 implants, weighted survival rate: 85.7% to 100%), Type 1C was SCV. The anterior mandible was the least-reported site (three studies, 42 implants, weighted survival rate: 98.5% to 100%). For the posterior mandible (13 studies, 447 implants, weighted survival rate: 95.0% to 100%), late placement + conventional loading (Type 4C) was SCV. It was not possible to perform a metaanalysis due to the limited number of controlled studies that had the same comparison and considerable heterogeneity in study design. CONCLUSION: Differences were found in the level of scientific evidence between the anterior and posterior and the maxilla and mandible, indicating that location is a consideration when selecting treatment protocol for a single implant.

Influence of Healing Period Upon Bone Turn Over on Maxillary Sinus Floor Augmentation Grafted Solely with Deproteinized Bovine Bone Mineral: A Prospective Human Histological and Clinical Trial.

PURPOSE: To investigate the influence of maturation timing upon histological, histomorphometric and clinical outcomes when deproteinized bovine bone mineral (DBBM) was used as a sole biomaterial for staged maxillary sinus floor augmentation (MSFA). MATERIALS AND METHODS: Patients with a posterior edentulous maxillary situation and a vertical bone height ≤ 4 mm were included in this study. A staged MSFA was carried out. After MSFA with DBBM as a sole grafting material, biopsy cores were harvested with simultaneous implant placement followed by a healing period of 5, 8, and 11 months, respectively. Micro-CT, histologic and histomorphometric analyses were performed. RESULTS: Forty-one patients were enrolled and 38 bone core biopsies were harvested. Significantly greater BV/TV was observed between 5- and 8-month healing from micro-CT analysis. Histomorphometric analyses showed the ratio of mineralized newly formed bone increased slightly from 5 to 11 months; however, no statistically significant difference was reached (p = .409). Residual bone substitute decreased from 37.3 ± 5.04% to 20.6 ± 7.45%, achieving a statistical significant difference from of 5 up to 11 months (p < .01). Moreover, no implant failure, biological or technical complication occurred after 12-month follow-up of functional loading. CONCLUSION: DBBM utilized as sole grafting material in staged MSFA demonstrated to be clinically effective regardless of the healing period. Histomorphometrical and micro-CT assessments revealed that at later stages of healing (8 and 11 months) there is a higher proportion of newly-bone formation compared to earlier stages (5 months). Moreover, the longer the maturation period, the substantially lesser remaining biomaterial could be expected. Even though, these facts did not seem to negatively impact on the implant prognosis 1-year after loading.

Accuracy of a real-time surgical navigation system for the placement of quad zygomatic implants in the severe atrophic maxilla: A pilot clinical study.

BACKGROUND: A real-time surgical navigation system potentially increases the accuracy when used for quad-zygomatic implant placement. PURPOSE: To evaluate the accuracy of a real-time surgical navigation system when used for quad zygomatic implant placement. MATERIALS AND METHODS: Patients with severely atrophic maxillae were prospectively recruited. Four trajectories for implants were planned, and zygomatic implants were placed using a real-time surgical navigation system. The planned-placed distance deviations at entry (entry deviation）points, exit (exit deviation) points, and angle deviation of axes (angle deviation) were measured on fused operation images. The differences of all the deviations between different groups, classified based on the lengths and locations of implants, were analysed. A P value of < 0.05 indicated statistical significance. RESULTS: Forty zygomatic implants were placed as planned in 10 patients. The entry deviation, exit deviation and angle deviation were 1.35 ± 0.75 mm, 2.15 mm ± 0.95 mm, and 2.05 ± 1.02 degrees, respectively. The differences of all deviations were not significant, irrespective of the lengths (P = .259, .158, and .914, respectively) or locations of the placed implants (P = .698, .072, and .602, respectively). CONCLUSION: A real-time surgical navigation system used for the placement of quad zygomatic implants demonstrated a high level of accuracy with only minimal planned-placed deviations, irrespective of the lengths or locations of the implants.

[Morphometric analysis of maxillofacial bone in 48 patients with ectodermal dysplasia].

PURPOSE: The study was performed to analyze the maxillofacial morphology of 48 patients with ectodermal dysplasia (ED) and to provide some reference for implant treatment of ED patients. METHODS: The study collected the clinical data and lateral cephalometric radiographs of 48 patients with ED treated between June 2013 and October 2016. The patients were grouped as follows: group 1, 23 patients, at least with two kinds of ectodermal disorder, besides hypodontia; group 2, 25 patients, only with one kind of ectodermal disorder, besides hypodontia. The number of missing teeth and maxillofacial cephalometric parameters were compared between 2 groups. SPSS 17.0 software package was performed for statistical analysis. RESULTS: The number of missing teeth was significantly larger in group 1(22.3±5.8) than group 2 (12±6.6) (P<0.05). The number of retained deciduous teeth was significantly larger in group 1 (8±4) than in group 2 (2.4±2.7) in females (P<0.05). Cephalometric analysis showed a reduced maxilla length (ANS-Ptm), retrusive maxilla (S-Ptm, SNA, NA-PA), a normal size (S-Co) and length (Co-Po) of mandible, a protruding mandible (NP-FH) and chin (Y axis), skeletal Angle Ⅲ malocclusion(ANB<0) and a reduced facial height (N-Me) in two groups. SNA, NA-PA, ANS-Ptm, S-Ptm and Y axis were significantly decreased and NP-FH was significantly increased in group 1 compared to group 2 in males (P<0.05). CONCLUSIONS: Maxillofacial morphology of ED patients typically presented a reduced maxilla length and retrusive maxilla, a normal size and length of mandible, a protruding mandible and chin, skeletal Angle Ⅲ malocclusion and a reduced facial height. The severity of abnormalities in maxillofacial bone morphology was correlated positively with absence of permanent teeth. Furthermore, retained deciduous teeth might have positive effect on the development of maxillofacial bone.

Influence of Posterior Mandibular Dimensions on Alveolar Bone Microarchitecture.

PURPOSE: The aim of this study was to investigate the influence of posterior mandibular dimensions (height and width at various levels) on alveolar bone microarchitecture using microcomputed tomography (micro-CT). MATERIALS AND METHODS: Partially edentulous subjects with one missing molar were included in the study. A bone core biopsy was performed at the site of planned implant surgery. For each patient, alveolar morphologic and architectural characteristics were analyzed using cone beam computed tomography (CBCT) and micro-CT imaging. Two parameters for height (apicocoronal residual height [RH] and residual ridge from inferior alveolar canal [RHN]) and three for buccolingual width (residual width at 5 mm [RW1], at 10 mm [RW2], and at 15 mm [RW3]) were determined using CBCT. Additionally, 10 parameters were obtained from micro-CT to determine microarchitecture. Pearson product-moment correlation coefficients were calculated to examine the correlation between the morphologic and microarchitectural variables. RESULTS: Significant positive correlations (P < .05) were found between RH and bone volumetric fraction (BV/TV) (rs = 0.34) and trabecular thickness (Tb.Th) (rs = 0.45). A significant negative correlation was found between RH and the bone-specific surface (BS/BV) (rs = -0.34). A strong significant negative correlation was found between trabecular spacing (Tb.Sp) and RW1 (rs = -0.42). None of the other variables reached statistical significance. CONCLUSION: Posterior mandibular dimensions may affect bony architectural characteristics.

Feasibility of Dental Implant Replacement in Failed Sites: A Systematic Review.

PURPOSE: To assess the clinical outcomes of replaced implants after removal of failed ones. In addition, associated risk factors that might affect the final outcome of these procedures were also explored. MATERIALS AND METHODS: An electronic literature search was conducted by two reviewers in several databases for articles written in English up to November 2014. Human clinical trials with a minimum of 10 subjects enrolled that reported clinical outcomes with a mean follow-up period of at least 12 months after implant replacement were included. Implant survival and nonmodifiable/modifiable factors at second and third implant placement attempts were studied. Hence, the PICO question that was aimed to be addressed was: Do patients undergoing implant replacement (second and third attempts) in previous failed sites have comparable clinical outcomes by means of implant survival/failure rate to implants placed at the first attempt? RESULTS: Five retrospective clinical cohort studies and two case series satisfied the selection criteria and thus were included in this review. In total, 396 patients were studied due to implant replacement in previous failed sites. The survival rate for implant replacement at the second attempt was 88.84% (390/439; range, 71% to 94.6%) with a mean follow-up of 41.59 ± 16.77 months. Thirty-one implants were replaced for a third attempt with a mean survival rate of 74.19% (23/31) at the follow-up of 29.66 ± 14.71 months. Major risk indicators were generally divided into patient-related factors (health status, smoking habits, and oral hygiene maintenance), implant characteristics (dimensions, coating, and loading), and site characteristics (bone quality and density, vertical and horizontal dimensions, soft tissue around the implant). CONCLUSION: Implant replacement is a reasonably feasible option for scenarios of early and late implant failure. However, modifiable risk factors must be controlled before proceeding for implant replacement.

Macrophage activating factor: A potential biomarker of periodontal health status.

OBJECTIVE: In periodontitis, activated macrophages not only initiate immune responses to periodontal-pathogen infections, but also damage the periodontal tissues by releasing a series of inflammatory cytokines. Macrophage-activating factor (MAF) and macrophage-chemotactic factor (MCF) are two important mediators involved in macrophage accumulation, activation and function. This study analyzed the levels of salivary MAF and MCF in healthy individuals and those with different periodontal diseases, and assessed the usefulness of salivary MAF and MCF as diagnostic biomarkers in periodontal tissue health status. DESIGN: Ninety-five saliva specimens were collected from healthy individuals (n=19), and patients with gingivitis (n=19), mild periodontitis (n=17), moderate periodontitis (n=20), and severe periodontitis (n=20). Pocket probing depth (PPD) and alveolar bone loss (ABL) were recorded via periodontal probing and dental radiography, respectively. Salivary MAF and MCF concentrations were assayed using enzyme-linked immunosorbent assays. RESULTS: MAF level tended to increase in saliva as periodontal diseases progressed (healthy periodontium

Expression of programmed death 1 ligand 1 on periodontal tissue cells as a possible protective feedback mechanism against periodontal tissue destruction.

Programmed death 1 ligand 1 (PD­L1) is a negative co­stimulatory molecule in immune responses. Previous reports have indicated that inflammatory cytokines can upregulate the expression of PD­L1 in tumor cells, which in turn suppresses host immune responses. Periodontitis is characterized by persistent inflammation of the periodontium, which is initiated by infection with oral bacteria and results in damage to cells and the matrices of the periodontal connective tissues. In the present study, the expression and function of PD­L1 in periodontal tissue destruction were examined. Periodontal ligament cells (PDLCs) were stimulated by inflammatory cytokines and periodontal pathogens. The expression and function of PD­L1 on the surface of PDLCs was investigated using flow cytometry in vitro. Periodontal disease was induced by the injection of Porphyromonas gingivalis in mouse models. The expression levels of PD­L1 in the periodontal tissues of the mice were analyzed using flow cytometry and immunohistochemistry. PD­L1 was inducibly expressed on the PDLCs by the inflammatory cytokines and periodontal pathogens. The inflammation­induced expression of PD­L1 was shown to cause the apoptosis of activated T lymphocytes and improve the survival of PDLCs. Furthermore, in the mouse model of experimental periodontitis, the expression of PD­L1 in severe cases of periodontitis was significantly lower, compared with that in mild cases. By contrast, no significant differences were observed between the healthy control and severe periodontitis groups. The results of the present study showed that the expression of PD­L1 may inhibit the destruction of periodontal tissues, indicating the involvement of a possible protective feedback mechanism against periodontal infection.

[Variations in protein concentration and albumin/globulin ratio of whole unstimulated saliva obtained from healthy people and patients with chronic periodontitis].

OBJECTIVE: We detected and analyzed the clinical values of total protein (TP), albumin (ALB), globulin (GLB), and ALB/GLB ratio (A/G) of whole unstimulated saliva of healthy people to determine the time of day when saliva composition is relatively stable. We compared the protein concentration and A/G of whole unstimulated saliva of patients with chronic periodontitis with those of healthy volunteers to provide references for diagnostic methods and clinical applications of saliva. METHODS: The whole saliva of 37 healthy subjects were collected at 8:00, 9:30, 11:30, 13:00, 16:30, and 21:00. Meanwhile, the whole saliva of 24 patients with periodontitis was collected in the morning. Bicinchoninic acid method was used to detect the TP content. Saliva ALB was detected by GF-D800 semi-automatic biochemical analyzer, and the GLB and A/G were calculated. Finally, the results were statistically analyzed using SPSS 19.0. RESULTS: Salivary protein compositions were stable in the morning on an empty stomach. Healthy people: TP, (1 354.35±389.52) µg.mL-1; ALB, (139.55±27.19) µg.mL-1; GLB, (1 211.80±360.73) µg.mL-1; A/G, 0.126 3±0.041 7. Subjects with chronic periodontitis: TP, (2 611.56±231.62) µg.mL-1; ALB, (296.27±17.34) µg.mL-1; GLB, (2 315.69±221.67) µg.mL-1; A/G, 0.156 2±0.017 3. The contents of TP, ALB, and GLB in healthy individuals at different periods within a day showed significant differences (P<0.05), which were mainly reflected in the levels before and after meals. No significant difference was detected in A/G. The concentrations of TP, ALB, and GLB were significantly increased in patients with chronic periodontitis compared with those in healthy volunteers. However, no significant difference existed in A/G. CONCLUSION: Salivary protein compositions are more stable in the morning than in other periods. Thus, mornings can be set as the time of specimen collection in future research. The concentrations of TP, ALB, and GLB in patients with chronic periodontitis are higher than those in healthy people.