The co-occurrence of the two main oral diseases: periodontitis and dental caries.

OBJECTIVES: Limited studies are available testing through multiple regression models the association between the two main oral diseases: dental caries and periodontitis. The aim of this cross-sectional population-based study was to verify whether dental caries and periodontitis co-occur in a representative sample of the South Korea population. MATERIALS AND METHODS: A total of 23,405 subjects representative of 36.2 million of adults (KNHANES) were examined. Univariate and multiple regression analyses using 7 different models were applied, controlling for age, gender, smoking status, frequency of toothbrushing, use of interproximal toothbrushes and flossing, educational level, income, gum diseases treatment and tooth filling in the previous year, BMI, Vitamin D serum levels, alcoholism, diabetes status, stress and carbohydrates dietary intake. RESULTS: In the fully adjusted model, participants with periodontitis had, respectively, a mean of 0.82 (95% CI: 0.41-1.23) and of 0.36 (95% CI: 0.22-0.50) more untreated decayed surfaces and teeth than participants without periodontitis, with an OR to have at least one untreated decayed surface of 1.96 (95% CI: 1.66-2.32). However, cumulative caries experience (DF scores) and periodontitis were not associated. CONCLUSIONS: In this large nationally representative population, periodontitis and untreated dental caries co-occur. However, when considering cumulative caries experience (DF scores), the two diseases do not appear related. CLINICAL RELEVANCE: In light of their possible co-occurrence, clinicians should implement integrative diagnostic, preventive and treatment strategies for both diseases.

Tooth extraction before radiotherapy is a risk factor for developing osteoradionecrosis of the jaws: A systematic review.

OBJECTIVES: The aim of this systematic review was to estimate the osteoradionecrosis rate in patients with head and neck cancer due to teeth extraction performed before radiotherapy and to identify possible risk factors. MATERIAL AND METHODS: PRISMA protocol was used to evaluate and present the results. PubMed, Scopus and Web of Science were used as search engines: English full-length papers of clinical studies, in peer-reviewed journals, were investigated. Cumulative meta-analysis was performed with a random effects model (PROSPERO registration code: CRD42018079986). RESULTS: Among 2,020 records screened, 8 were included in this review. Sixteen of 494 patients who underwent tooth extraction before radiotherapy developed osteoradionecrosis, with an osteoradionecrosis incidence of 2.2% (95% Confidence of Interval = 0.6-3.9, p < .185, I2  = 3,044%). All cases were reported in the mandible. No other clinical risk factor for osteoradionecrosis was detected. CONCLUSIONS: Even if it is generally recommended to remove oral foci before radiotherapy, this systematic review confirmed that teeth extractions before radiotherapy represent a risk factor for osteoradionecrosis; the considerable amount of missing data prevented us from identifying other possible risk factors for osteoradionecrosis onset. Major efforts should be done to perform sounder methodological clinical investigations.

Prevalence of signs and symptoms of temporo-mandibular disorder in patients with sleep apnea.

PURPOSE: The aim of the present study was to detect the prevalence of temporomandibular disorders (TMD) in patients with untreated obstructive sleep apnea (OSA) and to compare the results with healthy controls, matched for sex and age. METHODS: Forty-one consecutive patients with OSA were prospectively recruited from the Department of Otorhinolaryngology at the A. Gemelli Hospital prior to undergoing any treatment for OSA and independently of OSA severity. All patients underwent a complete TMD examination according to the diagnostic criteria for temporomandibular disorders (DC/TMD) protocol. The same examination was performed on 41 healthy controls matched for sex and age. Chi-squared test was used to compare results between the two groups. RESULTS: Of the 41 patients with OSA, 21 (51%) presented signs and/or symptoms of TMD compared to 13 of 41 subjects (32%) from the control group. Headache attributed to TMD and disc displacement with reduction were the most common diagnoses, with a statistically significant difference between the two groups (p<0.05). CONCLUSIONS: The prevalence of TMD signs and symptoms is significantly higher in untreated patients with OSA compared to healthy controls.

Hormone-related events and periodontitis in women.

AIM: While the short-term effects of hormonal events on gingival inflammation have been well described, long-term effects on the periodontium have received less attention. The aim of this cross-sectional population-based study was to evaluate the association between hormone-related events and periodontitis in a representative sample of the postmenopausal women of South Korea. MATERIALS AND METHODS: A total of 10,273 postmenopausal women representative of 6.1 million of Koreans were examined. Periodontitis and severe periodontitis were defined according to the Community Periodontal Index (CPI â‰§ 3 and CPI = 4, respectively). Univariate and multivariate regression analyses using 3 different models were applied controlling for age, smoking, marital status, educational level, income, BMI, hypertension, stress and frequency of toothbrushing. RESULTS: Severe periodontitis was directly associated with a longer reproductive life (p-trend = .027) and with a longer duration of breastfeeding (48-72 vs. 1-17 months: OR = 1.49; 95% CI: 1.01-2.21). Conversely, early menopausal age (<46 vs. 49-50 years: OR = 0.74; 95% CI: 0.56-0.97), history of artificial menopause (OR = 0.72; 95% CI: 0.53-0.97), having had more than 6 pregnancies (vs. 4: OR = 0.73; 95% CI: 0.55-0.97), having had more than three abortions (vs. 0: OR = 0.51; 95% CI: 0.28-0.93) and having had the first birth age >26 years (vs. <21 years: OR = 0.71; 95% CI: 0.52-0.97) were inversely associated with severe periodontitis. CONCLUSIONS: In this large nationally representative population, severe periodontitis was related to menopausal age, reproductive life length, number of pregnancies/abortions, first birth age and breastfeeding duration, while it was not to oral contraceptive and hormone replacement therapy usages.

Rate of malignant transformation of oral lichen planus: A systematic review.

OBJECTIVE: The aim of this study was to systematically review the literature to determine: (a) the malignant transformation rate (TR) of oral lichen planus (OLP) and its risk factors; (b) whether or not oral lichenoid lesions (OLL) have a different malignant TR. MATERIALS AND METHODS: PubMed, Scopus, and Web of Science were used as search engines: only observational, full-length, English language studies were investigated. PRISMA protocol was used to evaluate and present results. PROSPERO registration code is CRD42016048529. RESULTS: Among 7,429 records screened, only 21 were included in this review. Ninety-two of 6,559 patients developed oral squamous cell carcinoma, with an overall TR of 1.40% (1.37% for OLP and 2.43% for OLL), an annual TR of 0.20%. Female gender, red clinical forms, and tongue site seem to slightly increase the transformation risk. CONCLUSIONS: This systematic review confirms that both OLP and OLL, the latter with a slightly higher TR, may be considered potentially malignant disorders and suggest that erosive type, female gender and tongue site should be considered as risk factors for OLP transformation. Major efforts should be done to establish strict clinical and histological criteria to diagnose OLP and to perform sounder methodological observational studies.

Biomarkers in the gingival crevicular fluid used to detect root resorption in patients undergoing orthodontic treatment: A systematic review.

OBJECTIVES: To evaluate whether changes in the concentration of different biomarkers in the gingival crevicular fluid (GCF) can be used to detect the root resorption process in adult or adolescent patients undergoing treatment with a fixed appliance, in comparison with untreated subjects or treated patients not showing signs of root resorption. MATERIAL AND METHODS: The following databases were analysed in the period between June 2017 and March 2018, without any language and initial date restrictions: PubMed, EMBASE, Scopus, Web of Science and Cochrane Library. A quality assessment instrument (QAI) was developed to establish the risk of bias. RESULTS: A total of 1127 articles were analysed. Based on the inclusion and exclusion criteria, seven studies qualified for the final review. The QAI tool revealed that five articles were at a moderate risk of bias and two articles were at a low risk of bias. CONCLUSION: Dentine phosphoprotein (DPP) may be considered a relatively useful marker for root resorption. Dentinal sialoprotein (DSP) could be a potential biomarker but is not highly helpful at detecting root shortening. Inflammatory cytokines (pro- and anti-resorption), osteopontin (OPN), osteoprotegerin (OPG), RANKL and alkaline phosphatase (ALP) are useful biomarkers to explain the biological mechanisms that occur during orthodontic movement but are not specific enough. Further studies are required to clarify the role of GM-CSF as a potential biomarker to distinguish subjects at a risk of severe root resorption in the early phase.

Ultrasonographic Evaluation of The Effects of Orthodontic or Functional Orthopaedic Treatment on Masseter Muscles: A Systematic Review and Meta-Analysis.

Objectives: This review investigated the effects of orthodontic or functional orthopedic therapy on masseter muscle thickness through the use of ultrasonography (US) in growing subjects when compared with untreated subjects. Materials and Methods: This review systematically assessed studies that investigated growing subjects undergoing orthopedic therapy for the correction of malocclusion of vertical, sagittal and transversal plane. Electronic databases (CENTRAL, MEDLINE-PubMed, Scopus and Web of Science) were searched up to February 2019, including available RCTs and CCTs, without language restrictions. The primary outcome was the effect of orthopedic or functional treatment on masseter muscle thickness. The risk of bias of included studies was assessed through the Newcastle-Ottawa quality assessment scale with the aim of defining their methodological quality. A random-effects meta-analysis analyzing mean differences with 95% confidence intervals was used for quantitative analysis. Results: The search retrieved 749 titles, but the studies selection resulted in a final sample of 5 CCTs. The studies retrieved data from 233 children (age range: 5-22 years) and were conducted at university dental clinics. Children were treated for Class II malocclusion, increased vertical dimension or lateral cross-bite variably with rapid or slow maxillary expansion, twin block, bite block, mandibular activators, quad helix, alone or in combination. Risk of bias was assessed as medium for three studies, low for one and high for another. The meta-analysis determined that at the end of orthopedic or functional treatment masseter muscle thickness, measured through the use of US, is significantly reduced (MD -0.79 mm; 95% CI -1.28 to -0.31). The reduction in muscle thickness, therefore, could be considered an indicator for the evaluation of the success of therapy with orthodontic appliances. Conclusions: Although the meta-analysis revealed that US could be considered a less invasive and effective method to evaluate the masseter muscle thickness, single-blinded RCTs, are required to confirm US reliability in this field of application. This review was registered on PROSPERO with the following registration number: CRD42018068402.

Lay People Esthetic Evaluation of Primary Surgical Repair on Three-Dimensional Images of Cleft Lip and Palate Patients.

Background and Objectives: Previous literature has disclosed that facial attractiveness affects the esthetic evaluation of nose and lip deformity on frontal and lateral photographs. However, it has never been debated if the removal of the external facial features on three-dimensional (3D) models ("cropped assessment bias") could provide a considerable usefulness in the interpretation and comparison of the results. Additionally, it has been assumed on two-dimensional (2D) studies that esthetic assessment biases with respect to observer gender, and it is not acknowledged if and to the extent that "gender assessment bias" may be influenced by a three-dimensional layout. The aim of this study is to investigate if facial traits and observers' gender may affect the esthetic ratings of unilateral cleft lip and palate (UCLP) patients after soft tissue reconstruction. Materials and Methods: Three-dimensional images of ten UCLP patients' images were acquired before the intervention (T0), one-month (T1) and six-months (T2) postoperative. Geomagic® software (version 2014; 3D Systems, Rock Hill, SC, USA) was used to remove the external facial features of 3D surface models. Five-point scale developed by Asher-McDade et al. was used to rate both nasolabial attractiveness and impairment for full-face (FF) and cropped-face (CF) 3D images. Forty-three judges (21 males, 22 females) were enrolled for the esthetic evaluation. Intraclass correlation coefficient (ICC) was used to test intra- and inter-examiner reliability; a value of 0.7 was set as the minimum acceptable level of reliability. Results: When comparing the 2 sets of observations (FF and CF), the ICC ranged from 0.654 to 0.823. Concerning gender assessment bias, the ICC ranged from 0.438 to 0.686 and from 0.722 to 0.788 for males and females, respectively. Concerning inter-examiner reliability, ICC for questions 2-7 ranged from 0.448 to 0.644 and from 0.659 to 0.817 at T0 and T2, respectively. Conclusions: The removal of external facial features provides subtle differences on the esthetic assessment of UCLP patients. Moreover, based on our data, examiners' gender differences may affect esthetic assessment of UCLP patients. Despite the subjectivity of esthetic judgments, a reliable, validated and reproducible scoring protocol should consider the influence of gender differences on 3D esthetic assessment of UCLP patients.

Controlled release of 18-ß-glycyrrhetic acid by nanodelivery systems increases cytotoxicity on oral carcinoma cell line.

The topical treatment for oral mucosal diseases is often based on products optimized for dermatologic applications; consequently, a lower therapeutic effect may be present. 18-ß-glycyrrhetic acid (GA) is extracted from Glycirrhiza glabra. The first aim of this study was to test the cytotoxicity of GA on PE/CA-PJ15 cells. The second aim was to propose and test two different delivery systems, i.e. nanoparticles and fibers, to guarantee a controlled release of GA in vitro. We used chitosan and poly(lactic-co-glycolic) acid based nanoparticles and polylactic acid fibers. We tested both delivery systems in vitro on PE/CA-PJ15 cells and on normal human gingival fibroblasts (HGFs). The morphology of GA-loaded nanoparticles (GA-NPs) and fibers (GA-FBs) was investigated by electron microscopy and dynamic light scattering; GA release kinetics was studied spectrophotometrically. MTT test was used to assess GA cytotoxicity on both cancer and normal cells. Cells were exposed to different concentrations of GA (20-500 µmol l-1) administered as free GA (GA-f), and to GA-NPs or GA-FBs. ROS production was evaluated using dichlorodihydrofluorescein as a fluorescent probe. Regarding the cytotoxic effect of GA on PE/CA-PJ15 cells, the lowest TC50 value was 200 µmol l-1 when GA was added as GA-NPs. No cytotoxic effects were observed when GA was administered to HGFs. N-acetyl Cysteine reduced mortality induced by GA-f in PE/CA-PJ15 cells. The specific effect of GA on PE/CA-PJ15 cells is mainly due to the different sensitivity of cancer cells to ROS over-production; GA-NPs and GA-FBs formulations increase, in vitro, this toxic effect on oral cancer cells.

Periodontitis and platelet count: A new potential link with cardiovascular and other systemic inflammatory diseases.

AIM: As an infection-driven inflammatory disease, periodontitis could lead to a reactive increase in platelet count. This mechanism could partially mediate the well-documented association between periodontitis and atherosclerotic cardiovascular disease. The aim of this cross-sectional study was to test the presence of an association between periodontitis and platelet count in a representative sample of the South Korea population. MATERIALS AND METHODS: A total of 5,197 subjects representative of 34.9 million of adults were examined. Multivariate regression analyses were applied controlling for age, gender, smoking status, educational level, body mass index, alcoholism, diabetes and hypertension status, vitamin D serum levels and total cholesterol, triglycerides, HDL and LDL blood levels. RESULTS: Compared to the non-severe periodontitis group, subjects with severe periodontitis (CPI = 4) displayed 13,048.93 more platelets for µl of blood (95% CI: 3,296.26-22,801.61, p = 0.009) in the fully-adjusted model. The association between severe periodontitis and platelet count has shown to be highlighted in subjects aged more than 60 years, females, non-smokers and with normal HDL blood levels. A systemic inflammatory biomarker (white blood cell count) explained the 19.25% of this association. CONCLUSIONS: Within the limitations of this study, periodontitis-especially severe-is independently associated with a considerable increase in platelet count which is explained, at least in part, by an increase in the systemic inflammation.

Surgery-first orthognathic approach vs traditional orthognathic approach: Oral health-related quality of life assessed with 2 questionnaires.

INTRODUCTION: The purposes of the study were to investigate and evaluate the differences detected by the patients between the traditional orthognathic approach and the surgery-first one in terms of level of satisfaction and quality of life. METHODS: A total of 30 patients who underwent orthognathic surgery for correction of malocclusions were selected and included in this study. Fifteen patients were treated with the conventional orthognathic surgery approach, and 15 patients with the surgery-first approach. Variables were assessed through the Orthognathic Quality of Life Questionnaire and the Oral Health Impact Profile questionnaire and analyzed with 2-way repeated-measures analysis of variance. RESULTS: The results showed significant differences in terms of the Orthognathic Quality of Life Questionnaire (P <0.001) and the Oral Health Impact Profile (P <0.001) scores within groups between the first and last administrations of both questionnaires. Differences in the control group between first and second administrations were also significant. Questionnaire scores showed an immediate increase of quality of life after surgery in the surgery-first group and an initial worsening during orthodontic treatment in the traditional approach group followed by postoperative improvement. CONCLUSIONS: This study showed that the worsening of the facial profile during the traditional orthognathic surgery approach decompensation phase has a negative impact on the perception of patients' quality of life. Surgeons should consider the possibility of a surgery-first approach to prevent this occurrence.

N- and O-linked glycosylation site profiling of the human basic salivary proline-rich protein 3M.

In the present study, we show that the heterogeneous mixture of glycoforms of the basic salivary proline-rich protein 3M, encoded by PRB3-M locus, is a major component of the acidic soluble fraction of human whole saliva in the first years of life. Reversed-phase high-performance liquid chromatography with high-resolution electrospray ionization mass spectrometry analysis of the intact proteoforms before and after N-deglycosylation with Peptide-N-Glycosidase F and tandem mass spectrometry sequencing of peptides obtained after Endoproteinase GluC digestion allowed the structural characterization of the peptide backbone and identification of N- and O-glycosylation sites. The heterogeneous mixture of the proteoforms derives from the combination of 8 different neutral and sialylated glycans O-linked to Threonine 50, and 33 different glycans N-linked to Asparagine residues at positions 66, 87, 108, 129, 150, 171, 192, and 213.

Chrono-proteomics of human saliva: variations of the salivary proteome during human development.

An important contribution to the variability of any proteome is given by the time dimension that should be carefully considered to define physiological modifications. To this purpose, whole saliva proteome was investigated in a wide age range. Whole saliva was collected from 17 preterm newborns with a postconceptional age at birth of 178-217 days. In these subjects sample collection was performed serially starting immediately after birth and within about 1 year follow-up, gathering a total of 111 specimens. Furthermore, whole saliva was collected from 182 subjects aged between 0 and 17 years and from 23 adults aged between 27 and 57 years. The naturally occurring intact salivary proteome of the 316 samples was analyzed by low- and high-resolution HPLC-ESI-MS platforms. Proteins peculiar of the adults appeared in saliva with different time courses during human development. Acidic proline-rich proteins encoded by PRH2 locus and glycosylated basic proline-rich proteins encoded by PRB3 locus appeared following 180 days of postconceptional age, followed at 7 months (±2 weeks) by histatin 1, statherin, and P-B peptide. The other histatins and acidic proline-rich proteins encoded by PRH1 locus appeared in whole saliva of babies from 1 to 3 weeks after the normal term of delivery, S-type cystatins appeared at 1 year (±3 months), and basic proline-rich proteins appeared at 4 years (±1 year) of age. All of the proteinases involved in the maturation of salivary proteins were more active in preterm than in at-term newborns, on the basis of the truncated forms detected. The activity of the Fam20C kinase, involved in the phosphorylation of various proteins, started around 180 days of postconceptional age, slowly increased reaching values comparable to adults at about 2 years (±6 months) of age. Instead, MAPK14 involved in the phosphorylation of S100A9 was fully active since birth also in preterm newborns.

Effects of barriers on chemical and biological properties of two dual resin cements.

The aim of this study was to investigate the degree of conversion, monomer release, and cytotoxicity of two dual-cure resin cements (Cement-One and SmartCem2), light-cured across two indirect restorative materials in an attempt to simulate in vitro the clinical conditions. The results obtained show that the degree of conversion was influenced by both barriers, but the effect of the composite material was greater than that of the ceramic one. The amount of monomers released from the polymerized materials in the absence of barriers was significantly lower than that released in the presence of either the ceramic or the composite barrier. However, a higher amount of monomers was released in the presence of the ceramic barrier. All materials, in all the experimental conditions employed, induced slight cytotoxicity (5-10%) on human pulp cells. Our examinations showed that the two resin cements had similar chemical and biological properties. The decreased degree of conversion of the dual-curing self-adhesive composite showed that the light-curing component of these materials has an important role in the polymerization process. In clinical practice, it is therefore important to pay attention to the thickness of the material used for the reconstruction.

Top-down HPLC-ESI-MS detection of S-glutathionylated and S-cysteinylated derivatives of cystatin B and its 1-53 and 54-98 fragments in whole saliva of human preterm newborns.

Analysis by a HPLC-ESI-MS top-down proteomic platform of specimens of human preterm newborn whole saliva evidenced high relative amounts of cystatin B and its S-glutathionylated,S-cysteinylated, and S-S 2-mer (on Cys(3)) derivatives, decreasing as a function of postconceptional age (PCA). The percentage of S-unmodified cystatin B was higher than the S-modified isoforms in the early PCA period, differently from adults where cystatin B was detectable only as S-modified derivatives. The percentage of S-modified derivatives increased as a function of PCA, reaching at the normal term of delivery values similar to those determined in at-term newborns, babies, and adults. Moreover, in the early PCA period, high relative amounts of the 1-53 and 54-98 cystatin B fragments were detected, decreasing as a function of PCA and disappearing at the normal term of delivery. In agreement with intact cystatin B, fragment 1-53 was detectable as S-unmodified and S-modified derivatives, and their percentages changed accordingly with the percentages of intact proteins, suggesting that the fragmentation process could be subsequent to and independent from the S-modification of the protein. This study highlights specific enzymatic activity in the oral cavity of preterm newborns not present in at-term newborns and adults, which can be a clue to specialized pathways occurring during fetal oral development.

Top-down HPLC-ESI-MS characterization of rat gliadoralin A, a new member of the family of rat submandibular gland glutamine-rich proteins and potential substrate of transglutaminase.

During HPLC-ESI-MS/MS analysis of rat submandibular saliva secreted under isoprenaline stimulation, a protein with an experimental [M+H](1+) = 10,544.24 m/z was detected (17.5 ± 0.7 min). The MS/MS fragmentation pattern, manually investigated, allowed establishing an internal sequence in agreement with a DNA-derived sequence of an unknown rat protein coded D3Z9M3 (Swiss-Prot). To match the experimental MS/MS fragmentation pattern and protein mass with theoretical data, the removal from the N terminus of the signal peptide and from the C terminus of three amino acid (a.a.) residues (Arg-Ala-Val) and the cyclization of the N-terminal glutamine in pyroglutamic had to be supposed, resulting in a mature protein of 90 a.a. HPLC-ESI-MS/MS of the trypsin digest ensured 100% sequence coverage. For the high glutamine content (34/90 = 37.8%) we propose to name this protein rat gliadoralin A 1-90. Low amounts of five different isoforms were sporadically detected, which did not significantly change their relative amounts after stimulation. Gliadoralin A is substrate for transglutaminase-2, having Lys 60 and different Gln residues as major determinants for enzyme recognition. In silico investigation of superior structures evidenced that a small part of the protein adopts an α-helical fold, whereas large segments are unfolded, suggesting an unordered conformation.

Is Systemic Immunosuppression a Risk Factor for Oral Cancer? A Systematic Review and Meta-Analysis.

Even if the relationship between immunosuppression and increased incidence of systemic cancers is well known, there is less awareness about the risk of developing oral cancer in immunosuppressed patients. The aim of this review was to evaluate the association between immunosuppression and the development of oral cancer. Two authors independently and, in duplicate, conducted a systematic literature review of international journals and electronic databases (MEDLINE via OVID, Scopus, and Web of Science) from their inception to 28 April 2023. The assessment of risk of bias and overall quality of evidence was performed using the Newcastle-Ottawa Scale and GRADE system. A total of 2843 articles was identified, of which 44 met the inclusion criteria and were included in either the qualitative or quantitative analysis. The methodological quality of the included studies was generally high or moderate. The quantitative analysis of the studies revealed that immunosuppression should be considered a risk factor for the development of oral cancer, with a percentage of increased risk ranging from 0.2% to 1% (95% CI: 0.2% to 1.4%). In conclusion, the results suggest that a constant and accurate follow-up should be reserved for all immunosuppressed patients as a crucial strategy to intercept lesions that have an increased potential to evolve into oral cancer.

Oral Squamous Cell Carcinoma-Associated Thrombosis: What Evidence?

Venous thromboembolism (VTE) disease is the second leading cause of mortality in cancer patients. In the general population, the annual incidence of a thromboembolic event is about 117 cases per 100,000 persons, but cancer increases this risk about fourfold, while in patients receiving chemotherapy and surgical treatment, it is about sevenfold. Oral squamous cell carcinoma (OSCC) is the most common form of oral cancer and represents a multistep process in which environmental factors and genetic alterations are implicated. Thrombotic risk is considered empirically low in OSCC patients, although few data are available. Having limited information available may result in poor awareness of VTE prevention in OSCC, risking jeopardising the oncologic treatment and increasing the morbidity and mortality among these patients. In this paper, the topic of OSCC-associated thrombosis will be discussed.