Evaluation of the biological effect of mineral trioxide aggregate in inflamed pulp-in vivo analysis.

The health of dental pulp tissue is critical to maintaining normal tooth function from the eruption of permanent teeth to the formation of the apex. The study evaluated the inflamed pulp response to the mineral trioxide aggregate (MTA) after direct pulp capping with the mechanical pulp exposure in rats' incisor. Forty-eight mandibular central incisors of twenty-four Sprague-Dawley rats which were prepared with the cavities of one mm diameter, and the pulp exposures were randomly assigned into two groups: MTA group and calcium hydroxide (Ca(OH)2) group. The direct pulp capping was performed after three days and samples histological observations conduction within eight weeks. In both MTA and Ca(OH)2 groups, dentin -like structures were observed in the pulp tissues of some teeth. The number of teeth with reparative tissue in MTA group was statistically significantly higher than that in Ca(OH)2 group (p = 0.041). Inflammatory cell infiltration was found in the crown pulp tissues in two groups, and no statistical difference was observed between the two groups (p = 0.243). Pulp necrosis occurred in both groups, and there was no statistical difference between the two groups (p = 0.622). The results in this paper suggest that MTA promotes direct pulp capping and hence has certain potential clinical applications value in the treatments for the preservation of inflamed pulp.

Oral microbiome characteristics in children with and without early childhood caries.

OBJECTIVE: Early childhood caries (ECC) negatively affects children's growth due to its close relation to an imbalance of the oral microbiota. This study aimed to evaluate the distribution of the oral microbiota in children with ECC and healthy individuals. METHODS: The oral microbiota of 20 children with dental caries from both carious teeth (CC cohort) and healthy teeth (CH cohort), and the oral microbiota of 20 healthy control children (HH cohort) were subjected to 16S rDNA sequencing. RESULTS: The results revealed significant differences between the microbial structure of the CC and CH cohorts of every child with ECC. The most common microbes were Streptococcus, Neisseria, Leptotrichia, Lautropia and Haemophilus. Specifically, the CC cohort contained Lactobacillus, Veillonella, and Prevotella 7, the CH cohort contained Actinomyces, Bifidobacterium and Abiotrophia, and the HH cohort mainly contained Neisseria, Leptotrichia, Porphyromonas and Gemella. Lastly, we established a random forest model consisting of 10 genera (Prevotella 7, Actinobacillus, etc.) which demonstrated promising clinical diagnostic ability (area under the curve (AUC) = 89.8%). These findings indicate that oral microbiota can potentially be used as therapeutic targets or diagnostic markers for the early prediction and prevention of caries in children.

Trophic Niche Differentiation in Two Sympatric Nuthatch Species (Sitta yunnanensis and Sitta nagaensis).

Sympatric closely related species may experience interspecific trophic competition due to ecological similarity; they may isolate in terms of diet or habitat use as a strategy to avoid competition. The body tissues of consumers contain stable isotope signatures information that can be applied to infer their dietary information. In this study, δ13C and δ15N stable isotopes were analyzed to determine the dietary information and trophic niches of sympatric coexisting Sitta yunnanensis and Sitta nagaensis. The results showed that the food sources of S. yunnanensis and S. nagaensis were from six orders, including Orthoptera, and the cumulative contribution rate was 99.97%, with the two species eating similar diets but at different rates. The larger δ13C of S. yunnanensis indicates that it had a wider range of habitats for feeding, while the difference in δ15N values was not significant (p > 0.05), indicating that both species feed on similar nutrient levels. As determined by Bayesian ellipses, the isotopic niches of S. yunnanensis and S. nagaensis were differentiated; the isotopic niche width of S. yunnanensis is 2.69‱2, which was larger than that of S. nagaensis (0.73‱2), indicates that differentiation between the two species in diet or habitat use reduced competition. Trophic niche differentiation and differences in foraging proportions may be the principal resource allocation mechanisms behind S. yunnanensis and S. nagaensis coexistence.

Nest-Site Features and Breeding Ecology of Chestnut-Vented Nuthatch Sitta nagaensis in Southwestern China.

The breeding ecology of birds is the cornerstone of bird life-history theory, and breeding success directly affects the survival and development of populations. We studied the breeding ecology of a secondary cavity-nesting bird, the chestnut-vented nuthatch Sitta nagaensis, in southwestern China from March to June in 2020, 2021, and 2022. In total, 16 nests in nest boxes and 19 nests in natural cavities were studied. The nesting habitat was mainly Pinus yunnanensis forest (68.4%), and the nest trees were mainly P. yunnanensis and pear Pyrus spp. Cavities made by woodpeckers and knot holes were used as nest sites, and the nuthatches plastered the hole entrance with mud. The nesting material was mainly pine bark. The clutch size was 3.47 ± 0.56 (range 2-4, n = 30), with an incubation period of 16.06 ± 0.91 days (range 15-19 days, n = 18). The nestling period was 20.88 ± 1.90 days (range 18-23 days, n = 23), and both parents fed the nestlings.

Evaluation of heat-inactivated Limosilactobacillus fermentum CCFM1139 and its supernatant for the relief of experimental periodontitis in rats.

Periodontitis is a chronic inflammatory disease induced by subgingival microbial dysbiosis, characterised by inflammation of the soft tissues of the periodontium and progressive loss of alveolar bone. Limosilactobacillus fermentum CCFM1139 is a probiotic with the potential to relieve periodontitis in vitro and in vivo. Due to the cost of active strain in production applications, we considered the effectiveness of bacterial components and metabolites in alleviating experimental periodontitis. Therefore, this study investigated the effect of heat-inactivated Limosilactobacillus fermentum CCFM1139 and its supernatant in the development of experimental periodontitis through animal experiments. The results showed that active, heat-inactivated Limosilactobacillus fermentum CCFM1139 and its supernatant all significantly reduced IL-1ß levels in gingival tissue and serum (p < 0.05). Micro-computed tomography (micro CT) analysis showed that the active and heat-inactivated Limosilactobacillus fermentum CCFM1139 reduced alveolar bone loss in rats with periodontitis by 25.6% and 15.9% respectively (p < 0.05), with no change in percentage of bone volume (p > 0.05). In histomorphometric analysis, active Limosilactobacillus fermentum CCFM1139 showed better results in reducing alveolar bone loss and reducing inflammatory cell recruitment at the second molar. In addition, there was no significant difference in the number of tartrate-resistant acid phosphatase (TRAP) positive cells after in all experimental groups (p > 0.05). Therefore, heat-inactivated Limosilactobacillus fermentum CCFM1139 or its supernatant also have the ability to relieve periodontitis, and their alleviating effect may focus on the regulation of inflammatory response.

Lactiplantibacillus Plantarum CCFM8724 Reduces the Amounts of Oral Pathogens and Alters the Oral Microbiota in Children With Dental Caries: a Randomized, Double-Blind, Placebo-Controlled Trial.

Objective Early childhood caries (ECC) is closely related to the disorders of oral microbiota. Probiotics antagonize pathogenic bacteria and regulate the composition of the microbiota. We aimed to investigate the effects of Lactiplantibacillus plantarum CCFM8724 on Streptococcus mutans, Candida albicans, and oral microbiota of patients.Methods Children with ECC aged 3‒6 years were randomly divided into probiotic and placebo groups in the double-blind controlled trial. The intervention and washout periods were 28 days and 14 days, respectively. On days 1 and 28, dental plaques were collected. The effects of L. plantarum CCFM8724 on the oral microbiota of patients were investigated by sequencing the V3-V4 region of 16S rDNA. On days 1, 14, 28 and 42, qPCR was used to investigate the effect of L. plantarum CCFM8724 on the amounts of S. mutans and C. albicans in the saliva of children with ECC.Results L. plantarum CCFM8724 significantly reduced the amounts of S. mutans and C. albicans in saliva of children with ECC (p < 0.01). After consumption of L. plantarum CCFM8724, the abundance of Firmicutes, Granulicatella and Gemella increased, whereas the abundance of Proteobacteria, Neisseria, Bifidobacterium and Catonella decreased. Conclusion: Our results emphasize that probiotics could play a beneficial role in the prevention and treatment of ECC in children from an oral microecological perspective.

Effects of Limosilactobacillus fermentum CCFM1139 on experimental periodontitis in rats.

Periodontitis is a polymicrobial inflammatory disease often characterized by the excessive colonization of Porphyromonas gingivalis and Fusobacterium nucleatum, which causes alveolar bone resorption and advanced oral inflammation. This study aimed to evaluate the effect of Limosilactobacillus fermentum CCFM1139 on experimental periodontitis induced following ligature and infection with P. gingivalis and F. nucleatum in vivo. The results showed that L. fermentum CCFM1139 significantly reduced weight loss associated with periodontal inflammation (p < 0.05), while decreasing both the P. gingivalis and F. nucleatum populations within the oral cavity of rats (p < 0.05) and regulating the expression of tumor necrosis factor-alpha, interleukin (IL)-1 beta, and IL-8 in the periodontal tissue (p < 0.05). Microcomputed tomography (micro-CT) and histopathological examination revealed that L. fermentum CCFM1139 supplementation reduced the level of alveolar bone loss and bone porosity and increased bone volume (p < 0.05) in the experimental animals. Furthermore, L. fermentum CCFM1139 exhibited promising effects in preventing the deepening of the periodontal pocket and the increase in the gap between adjacent molars. Thus L. fermentum CCFM1139 was shown to have solid potential as an oral probiotic for protection against periodontitis suggesting that this may be a good candidate in the production of a new functional food for improving periodontitis.

[Relationships among tongue volume, hyoid position, airway volume and maxillofacial form in paediatric patients with Class â , Class â ¡ and Class â ¢ malocclusions].

PURPOSE: To investigate the relationships among tongue volume, hyoid position, airway volume and maxillofacial form in paediatric patients with Class Ⅰ, Class Ⅱ and Class Ⅲ malocclusion. METHODS: Data of 112 children with malocclusion in the Department of Stomatology, Wuxi Children's Hospital from December 2015 to December 2018 were collected. The children were divided into three groups according to Angle's classification: Class Ⅰ (n=42), Class Ⅱ (n=38) and Class Ⅲ (n=32). Tongue volume was evaluated by oral B-ultrasound, the hyoid position was obtained by lateral cephalogram, then the airway volume and maxillofacial form were evaluated by cone-beam CT (CBCT). Relationship among tongue volume, hyoid position, airway volume and maxillofacial form were analyzed. The data were processed by SPSS 20.0 software package. RESULTS: The tongue volume of Class III was significantly larger than that of Class I and Class II (P<0.05); H-FH and H-MP of Class II were significantly larger than those of Class I and Class III, and H-VL was significantly smaller than that of Class I and Class III (P<0.05). H-FH and H-MP of Class III were significantly smaller than those of Class I, and H-S was significantly larger than that of Class I (P<0.05); V throat of three types was the largest in Class Ⅲ, followed by Class I and Class Ⅱ, with significant difference (P<0.05). V nose of three types was the largest in Class Ⅱ, followed by Class I and Class Ⅲ, with significant difference (P<0.05). SNB angle of three types was the largest in Class Ⅲ, followed by Class Ⅰ and Class Ⅱ, with significant difference (P<0.05). ANB angle was the largest in Class I, followed by Class Ⅱ and Class Ⅲ, with significant difference (P<0.05). Tongue volume was positively correlated with V throat, V nose, and SNB, and negatively correlated with H-FH and ANB (P<0.05). H-FH and H-MP were negatively correlated with SNB angle and positively correlated with H-MP and ANB angle (P<0.05). CONCLUSIONS: Children with Class Ⅲ malocclusion have larger tongue volume, upward displacement of hyoid, and smaller nasopharyngeal volume. Children with Class II malocclusion have small tongue volume, downward displacement of hyoid, and small oropharyngeal volume. Tongue volume, hyoid position, airway volume and maxillofacial form are significantly correlated in paediatric patients with malocclusions, the influence of mandibular recession on the shape of upper airway should be considered during orthodontic treatment, in order to achieve the best aesthetic and therapeutic effects.

Inhibitory and preventive effects of Lactobacillus plantarum FB-T9 on dental caries in rats.

Streptococcus mutans is recognized as the main cause of dental caries, and the formation of a plaque biofilm is required for caries development. This study aimed to determine the inhibitory effect of Lactobacillus plantarum FB-T9 on S. mutans biofilm formation in vitro and on the prevention and treatment of dental caries in rats. During in vitro experiments, FB-T9 exhibited good bacteriostatic ability in a plate competition assay. This strain also significantly reduced the biomass and viability of S. mutans biofilms and induced structural damage during the early (6 h), middle (12 h) and late (24 h) stages of biofilm formation. In a 70-day in vivo experiment, FB-T9 significantly reduced the levels of S. mutans on the dental surfaces of rats by more than 2 orders of magnitude of the levels in the dental caries model group (p < 0.05). Moreover, FB-T9 significantly reduced the caries scores (modified Keyes scoring method) in both the prevention and treatment groups (p < 0.05) and had great colonization potential in the oral cavity. These results indicate the potential usefulness of L. plantarum FB-T9 as a probiotic for the prevention and treatment of caries.

Inhibitory Effect of Lactobacillus plantarum CCFM8724 towards Streptococcus mutans- and Candida albicans-Induced Caries in Rats.

Streptococcus mutans is a recognized cariogenic bacterium and a major producer of biofilm matrix. The presence of Candida albicans in dental plaque with S. mutans enhances the virulence leading to the onset of rampant caries which is similar to early childhood caries (ECC). The purpose of this study was to explore the effect of Lactobacillus plantarum CCFM8724 (CCFM8724) on the treatment and prevention of dental caries induced by S. mutans and C. albicans in vivo. Rats were divided into 6 groups: the control group and model group, 2 treatment groups, and 2 prevention groups (0.02% chlorhexidine or CCFM8724). The fluctuation of microbial colonization and the change of bacteria flora in rat oral cavity after sowing of L. plantarum CCFM8724 were investigated by colony-forming units (CFU) and microflora analysis. The caries of rats were assessed by microcomputed tomography (micro-CT) and Keyes scoring method. The results showed that L. plantarum CCFM8724 in both the treatment and prevention groups could significantly decrease the population of S. mutans and C. albicans in the rats' oral cavity (p < 0.001), the mineral loss of enamel (p < 0.05), and the scores of caries (p < 0.05). Besides, L. plantarum CCFM8724 exhibited better effects than chlorhexidine. Hence, L. plantarum CCFM8724 was proved to be a potential oral probiotic on caries treatment and prevention in vivo and it may have the prospect of application in dental caries (especially ECC) prevention products.

[Serum levels of sVCAM-1, IL-18 and VEGF in patients with aplastic anemia and their clinical significance].

This study was purposed to investigate the serum levels of soluble intracellular adhesion molecule (sVCAM-1), interleukin 18 (IL-18) and vascular endothelial growth factor (VEGF) in patients with aplastic anemia (AA) and their clinical significance. Enzyme linked immunosorbent assay (ELISA) was used to detect sVCAM-1, IL-18 and VEGF in serums of 30 patients with AA and 25 normal controls. The results showed that the serum levels of sVCAM-1 and IL-18 in patients with AA [(839.08 +/- 173.97) ng/ml, (380.35 +/- 47.76) pg/ml] were significantly higher than those in normal controls [(538.16 +/- 91.21) ng/ml, (256.39 +/- 59.52) pg/ml] (p < 0.01; p < 0.01). The levels of sVCAM-1 and IL-18 in severe AA patients [(969.94 +/- 182.54) ng/ml, (388.96 +/- 46.06) pg/ml] were higher than those in chronic AA patients [(709.26 +/- 165.32) ng/ml, IL-18 (352.21 +/- 47.08) pg/ml] (p < 0.01; p < 0.05), but the level of VEGF in AA patients [(69.63 +/- 27.42) pg/ml] was lower than that in the normal controls [(125.62 +/- 32.15) pg/ml] (p < 0.01)]. The level of VEGF in severe AA patients [(51.30 +/- 29.86) pg/ml] was significantly lower than that in chronic AA patients [(80.02 +/- 25.14) pg/ml] (p < 0.01). The levels of sVCAM-1 and IL-18 in AA patients after treatment were lower than those before treatment (p < 0.01; p < 0.05), but the level of VEGF after treatment was significantly higher than that before treatment (p < 0.05). It is concluded that the high levels of sVCAM-1, IL-18 and low level of VEGF in serum may be involved in the pathogenesis and progress of AA.