[Hora est. The relationship between stress, salivary proteins and caries experience in children]. / Serie: Hora est. De relatie tussen stress, speekseleiwitten en cariëservaring bij kinderen.

Dental caries is a major public health problem and untreated caries has serious consequences for children. Psychosocial factors have multiple consequences, among others on the composition of saliva. Therefore, this study investigated whether stress and various salivary protein levels are associated with dental caries experience in children. The activity of the Matrix Metalloproteinases MMP-8 and MMP-9 and the total proteolytic activity in saliva turned out to be indicators for the caries experience. Salivary Alpha-Amylase seems to be a protector and was a strong indicator for caries experience. In cases where children were exposed to two different dental treatments, the level of salivary cortisol- and alpha-amylase increased, in which a distinction could be made between non-invasive and invasive treatment. The results of the study emphasise the need for further research into the way stress and salivary protein concentrations can affect the caries experience and how different dental treatments can influence the behaviour and stress levels in children.

Circle of Willis: anatomical variations of configuration. A magnetic resonance angiography study.

BACKGROUND: The main scope of this paper is to investigate the prevalence of the anatomical variants of the circle of Willis (CoW) in the Romanian population through magnetic resonance angiography. MATERIALS AND METHODS: Magnetic resonance angiography images were obtained for 126 individuals and the configurations of the anterior and posterior CoW were identified, and classified. The prevalence of each variant and the number of complete anterior or posterior parts of the circle were determined. RESULTS: A classical configuration of the CoW was found in 39 (30.9%) cases. The most common posterior variation was the unilateral absence of a posterior communicating artery (n = 28) while in the anterior circle it was the unilateral absence of the precommunicating segment of an anterior cerebral artery (n = 17). A complete entire CoW was found in 63 cases, while the anterior and posterior parts yielded complete configurations in 108 and 73 cases, respectively. Eight cases did not present complete configurations. A foetal posterior communicating artery was identified unilaterally in 14 cases and bilaterally in 6 cases. CONCLUSIONS: Unilateral variations were the most common changes found in CoW configuration. The correct assessment of the CoW configuration may prove useful in the planning and follow-up of brain surgery and interventional procedures, as well as in estimating the prognosis of patients suffering from stroke or other related cerebral vascular events.

Immunohistochemical expression of non-collagenous extracellular matrix molecules involved in tertiary dentinogenesis following direct pulp capping: a systematic review.

BACKGROUND: Extracellular matrix molecules (ECMM) expression during tertiary dentinogenesis provides useful information for regenerative applications and efficacy of pulp capping materials. AIM: To identify and review the expression and roles of non-collagenous ECMM after successful direct pulp capping (DPC), following mechanical pulp exposures, via immunohistochemistry (IHC). The study addressed the question of where will successful DPC impact the IHC expression of these molecules. DATA SOURCES: In vivo animal and human original clinical studies reporting on ECMM in relation to different follow-up periods were screened and evaluated via descriptive analysis. The electronic literature search was carried out in three databases (MEDLINE/PubMed, Web of Science, Scopus), followed by manual screening of relevant journals and cross-referencing, up to December 2018. STUDY ELIGIBILITY CRITERIA, PARTICIPANTS, AND INTERVENTIONS: Randomized and non-randomized controlled trials, conducted in humans and animals, were selected. Histological evidence for tertiary dentine formation was a prerequisite for IHC evaluation. STUDY APPRAISAL AND SYNTHESIS METHODS: The methodological quality of the included articles was independently assessed using the Systematic Review Centre for Laboratory animal Experimentation (SYRCLE) and the Cochrane risk of bias tool (RoB 1), respectively. RESULTS: From a total of 1534 identified studies, 18 were included. Thirteen papers evaluated animal subjects and five studies were carried out on humans. In animals and humans, fibronectin and tenascin expressions were detected in pulp and odontoblast-like cells (OLC); dentine sialoprotein was expressed in both soft and newly-formed mineralized tissue. In animals, bone sialoprotein was early expressed, in association with OLC and predentin; the immunoreactivity for dentine sialophosphoprotein and dentine matrix protein-1 was associated with the OLC and dentine bridge; osteopontin was expressed in OLC, predentine and reparative dentine. A considerable heterogeneity was found in the methodologies of the included studies, as well as interspecies variability of results in terms of time. CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS: Within the limited scientific evidence, all non-collagenous ECMM expressions during tertiary dentinogenesis are active and related to soft and hard tissues. There is a shortage of human studies, and future research directions should focus more on them. PROSPERO Protocol: CRD42019121304.

Evaluation of a hydrophobic gel adhering to the gingiva in comparison with a standard water-soluble 1% chlorhexidine gel after scaling and root planing in patients with moderate chronic periodontitis. A randomized clinical trial.

OBJECTIVES: To evaluate the clinical, microbiological and enzymatic activity of a hydrophobic chlorhexidine-based gingiva-adhering gel containing herbal ingredients, compared with a commercially available 1% chlorhexidine water-soluble gel, during non-surgical therapy of moderate chronic periodontitis. METHODS: A total of 34 subjects participated in this 6-month blinded randomized parallel controlled trial (ISRCTN35210084). After scaling and root planing (SRP), test group received the gel, by rubbing on the gingiva, once every second day, for 14 days. The control group received the control gel twice daily. Clinical parameters considered were the approximal plaque index, simplified oral hygiene index, modified gingival index, bleeding on probing, probing depth and clinical attachment level (primary outcome), assessed at baseline, 3 and 6 months, together with the frequency of detection of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis (P.g.), Prevotella intermedia, Treponema denticola (T.d.), Tannerella forsythia (T.f.), and activity of neutrophil elastase and myeloperoxidase (secondary outcomes). RESULTS: At 3 and 6 months, all clinical parameters improved significantly, without significant intergroup differences, except OHI-S, which improved at 3 months (P < 0.05). Microbiological data resulted in no significant intergroup differences at baseline and 6 months. At 3 months, significant differences for P.g., T.f. and T.d. were noted. A significant reduction of neutrophil elastase after 3 and 6 months was observed (P < 0.005), without significant intergroup differences. For myeloperoxidase, significant reductions were noted in both groups (P < 0.005 and P < 0.05), but no significant intergroup differences. The tested product seemed to have an increased efficacy, due to longer persistence on the gingiva, with reduced application frequency. CONCLUSIONS: Both products had a relatively similar influence on the clinical, microbiological and enzymatic outcomes at 3 and 6 months after SRP.

Embryonic hematopoietic stem cells and interstitial Cajal cells in the hindgut of late stage human embryos: evidence and hypotheses.

There have been few studies on human embryos describing a specific pattern of hindgut colonization by hematopoietic stem cells (HSCs) and interstitial Cajal cells (ICCs). We aimed to study CD34, CD45 and CD117/c-kit expression in late stage human embryos, to attain observational data that could be related to studies on the aorta-gonad-mesonephros (AGM)-derived HSCs, and data on hindgut ICCs. Antibodies were also applied to identify alpha-smooth muscle actin and neurofilaments. Six human embryos of 48-56 days were used. In the 48 day embryo, the hindgut was sporadically populated by c-kit+ ICCs, but, in all other embryos, a layer of myenteric ICCs had been established. Intraneural c-kit+ cells were found in pelvic nerves and vagal trunks, suggesting that the theory of Ramon y Cajal assuming that ICCs may be primitive neurons may not be so invalid. Also in the 48 day embryo, c-kit+/CD45+ perivascular cells were found along the pelvic neurovascular axes, suggesting that not only liver, but also other organs could be seeded with HSCs from the AGM region. CD45+ cells with dendritic morphologies were found in all hindgut layers, including the epithelium. This last evidence is suggestive of an AGM contribution to the tissue resident macrophages and could be related to processes of sprouting angiogenesis which, in turn, have been found to be guided by filopodia of endothelial tip cells. Further studies on human embryonic and fetal material should be performed to attempt to clarify whether the hindgut colonization with HSCs is a transitory or definitive process.

Human adult dental pulp CD117/c-kit-positive networks of stromal cells.

Dental pulp tissue was collected from 6 healthy adult patients, prior to prosthetic treatments, in order to evaluate the in situ phenotype of dental pulp stromal cells and compare with that of dental pulp stem cells. A CD34-/CD44+/CD105-/CD117+/CD146-/nestin- phenotype of stromal cells in the dental pulp core was found. Cells with a similar phenotype, but CD44-, were found in the cell richzone. Dental pulp stromal networks (DPSNs) were found CD117+/CD44+ in the pulp core, but CD117+/CD44- in the cell rich zone. The c-kit-positive DPSNs were contacting pulp nerves and were, in this regard only, comparable to interstitial Cajal cells. Stromal signalling in dental pulp needs further evaluation, in normal tissue as well as a possible cause of persisting pain after endodontic treatments.

Novel method for proliferation of oral keratinocyte stem cells.

BACKGROUND AND OBJECTIVE: Stem cell-based tissue engineering offers clear advantages over conventional normal cell approaches. Owing to their specific characteristics, oral keratinocyte stem cells represent an attractive solution for therapeutic applications. However, when cultured in vitro, these cells lose their unique properties, acquiring a limited capacity for self-renewal, and differentiate rapidly into normal functional keratinocytes. The main aim of the present study was to develop an in-vitro method for the expansion of oral keratinocyte stem cells using a biomaterial approach. MATERIAL AND METHODS: Oral keratinocyte stem cells were isolated based on the identification of two surface markers - integrin α6ß4 and CD71 - using a magnetic method. The cells were cultured on specific substrates formed from blends of polymers: poly(lactide-co-glycolide) (PLGA); poly(lactide-co-glycolide) + polyurethane (PLGA + PU); and poly(lactide-co-glycolide) + extracellular matrix (PLGA + ECM). The polymers were deposited using a laser-based technique - matrix-assisted pulsed laser evaporation. The cells were analyzed for cell size, cell proliferation, colony-forming efficiency, cell adhesion markers (such as E-cadherin and beta 1 integrin), keratinocyte stem cells and differentiation markers. The methods included ELISAs, immunofluorescence and atomic force microscopy imaging. RESULTS: After 14 d in culture, cells seeded on PLGA + PU stained positive for p63, cd44H, cytokeratin 19 and integrin α6ß4 and negative for involucrin, cytokeratin 14 and cytokeratin 10. The levels of adhesion molecules were significantly increased in cells grown on PLGA + PU: at 14 d the E-cadherin levels were 5.4 ± 0.2 ng/mL (for cells grown on PLGA + PU) vs. 4.1 ± 0.4 ng/mL (for cells grown on control medium) (n = 5, p < 0.05 Bonferroni). Oral keratinocyte stem cells grown on PLGA + PU had the highest colony-forming efficiency and proliferation rate, together with the smallest cell size, compared with cells grown on control medium or other polymeric substrates. CONCLUSION: The present study demonstrates that by culturing oral keratinocyte stem cells on PLGA blended with PU it is possible to preserve their phenotype in vitro and to guide their short-term expansion and proliferation. Certain stem-cell characteristics are preserved and their short-term expansion may be enhanced.

Zipper-like series of desmosomes supported by subplasmalemmal actin belts in thymic epithelial reticular cells in the rat.

Remodeling of epithelial tissues requires coordinated cell migration. Most of the mechanisms regulating desmosome assembly and stability in migrating epithelial cells are still unknown. The actin cytoskeleton is a significant component of desmosome assembly and maturation. The association of the actin cytoskeleton with adherens junctions requires additional ultrastructural investigations. A transmission electron microscopic study was performed on five samples of rat thymus. Interepithelial series of desmosomes up to 6.5 µm length were found as were composite series of junctions (tight, adherens, and desmosomes). As a particular feature, subplasmalemmal belts of microfilaments, apparently of actin, ran adjacent to the inner dense plaques of desmosomes, passing beneath and at a distance to the tight junctions. They were not found beneath the adherens junctions. The series of desmosomes were termed zipper-like desmosomes (ZLDs), and were either complete, or imperfect. Terminal imperfect or incomplete desmosomes were found at the ends of the zipper-like series. Alpha-smooth muscle actin immune labeling on six other samples of rat thymus was strongly suggestive of the existence of subplasmalemmal actin belts in the epithelial reticular system. Further studies are needed to establish the exact role of the ZLDs during processes of epithelial remodeling.

The extramandibular inferior alveolar nerve in cases with severely atrophic lower jaws.

There are very few evidences on the extramandibular course (EMC) of the inferior alveolar nerve (IAN). We report here two such cases. The first one was encountered at dissection, in a human adult female cadaver where the right IAN terminal division was identified in the premolar region, above a severely atrophied mandibular body. The second case was a patient evaluated by cone-beam CT, who presented with an extremely atrophic mandible with bilateral extramandibular courses of the IANs. Such severe atrophy of the mandible may be considered as residual ridge class 7 along with the existing Atwood classes. EMCs of the IAN may not only occur in extreme mandibular atrophy, but also in dentate mandibles. In edentulous mandibles, an extramandibular IAN may complicate local surgical procedures or hamper denture wearing.

Evidence of nNOS and ChAT positive phenotypes in nervous ganglia of the retrostyloid space.

The cholinergic and nitrergic phenotypes in human fetal ganglia (inferior) of the glossopharyngeal and vagus nerves were overlooked in basic research. Lack of a positive neuronal NO synthase (nNOS) phenotype in the inferior vagal fetal ganglion was recently suggested to be an individually variable phenotype. Choline acetyltransferase (ChAT) was not evaluated previously in ontogenesis. We aimed to evaluate these phenotypes in human midterm fetuses. Samples from five specimens with gestational ages varying from 4 to 6 months were used. Immunohistochemistry for nNOS, ChAT, neurofilaments, and S100 protein was performed. Neuronal somata were positively stained for nNOS, ChAT and neurofilaments in the inferior glossopharyngeal and vagal ganglia. S100 protein distinctively labelled the satellite glial cells ensheating the respective neurons. In human midterm fetuses vagal and glossopharyngeal inferior ganglia are nitrergic and cholinergic. To evaluate a functional role of these phenotypes in ontogenesis, the specific anatomic circuits should be further checked. Differences in immune labelling should be evaluated by use of similar antibodies from different manufacturers.

Investigation of six selected bacterial species in endo-periodontal lesions.

AIM: To investigate and determine possible associations of six tested bacteria belonging to 'orange' and 'green' complexes, in endo-periodontal lesions: Parvimonas micra, Fusobacterium nucleatum, Campylobacter rectus, Eubacterium nodatum, Eikenella corrodens and Capnocytophaga sputigena. METHODOLOGY: Forty-six patients presenting with different types of endo-periodontal lesions were investigated. Clinical examinations, periapical radiographs and microbiological sampling from the canal system (endo) and periodontal pockets (perio) were performed. Qualitative and semiquantitative evaluation of bacteria was performed by polymerase chain reaction (PCR) and DNA-DNA hybridization (micro-IDent plus; Hain Lifescience, Germany). RESULTS: Extremely high bacterial loads in endodontic samples were recorded for P. micra, F. nucleatum and C. sputigena, while periodontal samples were often colonized by the same species, plus C. rectus. Significant association was recorded between F. nucleatum-endo and P. micra-endo (P = 0.03, Fisher's exact test). There was marginal evidence of associations between: (i) C. sputigena-endo and C. sputigena-perio (P = 0.06, Fisher's exact test); (ii) P. micra-endo and P. micra-perio (P = 0.05, Fisher's exact test). Sensitivity to percussion was associated with an increased chance of cases with P. micra-endo (P = 0.03, Pearson chi-square test). CONCLUSION: The findings suggest that F. nucleatum, P. micra and C. sputigena may play a role in the pathogenesis of endo-periodontal lesions.

Prospective clinical study evaluating the long-time adjunctive use of chlorhexidine after one-stage full-mouth SRP.

OBJECTIVES: Scaling and root planing are the causal procedure in the treatment of periodontitis. Many attempts have been made to improve the outcome. The aim of this study was to verify the influence of the extended use of chlorhexidine after one-stage full-mouth (FM) SRP in patients with chronic periodontitis on the clinical outcome after 3 months. METHODS: Eighty-one patients with pockets > or =5 mm were treated by FM. All patients rinsed additionally with 0.2% chlorhexidine (CHX) twice daily over 3 months. Plaque index, bleeding on probing, probing depth (PD) and clinical attachment level (CAL) were recorded at baseline and after 1 and 3 months. RESULTS: In the test group, all variables were significantly improved after 1 and 3 months. Mean reduction of PD and CAL gain was 2.25 +/- 1.08 and 1.67 +/- 1.08 after 1 and 2.99 +/- 1.11 and 2.33 +/- 1.31 after 3 months respectively. CONCLUSIONS: Over 3 months of extended use of CHX mouth rinse after SRP showed slightly but statistically significant better results.

[Clinical and therapeutical considerations regarding odontogenic acute mediastinitis]. / Consideratii clinico-terapeutice în mediastinitele acute de cauza dentara.

Odontogenic acute mediastinitis is an polymicrobial infections caused in most cases by gram negative and anaerobic germs. The odontogenic origin of the cases in this study was based on anamnestic inquiry of the patients, which reveales a dental treatment 7-15 days before the diagnosis of acute mediastinitis was established. Clinical features are often nonspecific at the debut of this affection; septic shock could appear suddenly associated with multiple systems and organs failure. This is the explication why, some of these patients presented septic shock when are diagnosed. In this situations, when acute mediastinitis is suspected, based on clinical and imaging findings, it must be confirmed by surgical exploration and perioperative bacteriological evaluations. Positive diagnosis is based on clinical features associated with labs and imaging studies. Surgery plays an important role in therapy of acute mediastinitis: debridement and drainage of mediastinum with subsequently lavage of it, using antiseptic solutions. Broad spectrum antibiotherapy should be administrated immediately, before antibiogram is ready.

Oxidative stress markers in oral lichen planus.

Oral lichen planus (OLP) is a relatively common disorder whose cause is still unknown. Oral cancer is preceded in most cases by pre malignant lesions-leukoplasia, submucous fibrosis and lichen planus. Free radicals and reactive oxygen species play important roles in both pathogenesis of lichen planus and carcinogenesis. Thus monitoring systemic and saliva compounds important for the antioxidant defence (oxidative balance) could be important for the clinician's treatment strategy. Thorough medical management and early active treatment are necessary to improve symptoms and might also be a relevant prevention strategy from squamous cell carcinoma risk, although data to fully support this statement still need investigation. The principal aim of this study was to determine the systemic uric acid, GGT, and albumin levels as well as the levels of uric acid and albumin in 20 patients diagnosed with lichen planus and 20 controls. Extensive medline search failed to reveal any study of this type. Our results showed a significant decrease of saliva (p < 0.005) uric acid and an increase in serum gamma glutamyl transpherase (GGT) (p < 0.01) as well as in the total antioxidant capacity of saliva in patient group with respect to the control one. The preliminary conclusion of our study is that uric acid, the most important salivary antioxidant and GGT could be considered in the future as useful markers of oxidative stress for elaboration of treatment strategy and monitoring.