Experts consensus on the procedure of dental operative microscope in endodontics and operative dentistry / 国际口腔科学杂志·英文版

The dental operative microscope has been widely employed in the field of dentistry, particularly in endodontics and operative dentistry, resulting in significant advancements in the effectiveness of root canal therapy, endodontic surgery, and dental restoration. However, the improper use of this microscope continues to be common in clinical settings, primarily due to operators' insufficient understanding and proficiency in both the features and established operating procedures of this equipment. In October 2019, Professor Jingping Liang, Vice Chairman of the Society of Cariology and Endodontology, Chinese Stomatological Association, organized a consensus meeting with Chinese experts in endodontics and operative dentistry. The objective of this meeting was to establish a standard operation procedure for the dental operative microscope. Subsequently, a consensus was reached and officially issued. Over the span of about four years, the content of this consensus has been further developed and improved through practical experience.

Fibroblast membrane-camouflaged nanoparticles for inflammation treatment in the early stage / 国际口腔科学杂志·英文版

Unrestrained inflammation is harmful to tissue repair and regeneration. Immune cell membrane-camouflaged nanoparticles have been proven to show promise as inflammation targets and multitargeted inflammation controls in the treatment of severe inflammation. Prevention and early intervention of inflammation can reduce the risk of irreversible tissue damage and loss of function, but no cell membrane-camouflaged nanotechnology has been reported to achieve stage-specific treatment in these conditions. In this study, we investigated the prophylactic and therapeutic efficacy of fibroblast membrane-camouflaged nanoparticles for topical treatment of early inflammation (early pulpitis as the model) with the help of in-depth bioinformatics and molecular biology investigations in vitro and in vivo. Nanoparticles have been proven to act as sentinels to detect and competitively neutralize invasive Escherichia coli lipopolysaccharide (E. coli LPS) with resident fibroblasts to effectively inhibit the activation of intricate signaling pathways. Moreover, nanoparticles can alleviate the secretion of multiple inflammatory cytokines to achieve multitargeted anti-inflammatory effects, attenuating inflammatory conditions in the early stage. Our work verified the feasibility of fibroblast membrane-camouflaged nanoparticles for inflammation treatment in the early stage, which widens the potential cell types for inflammation regulation.

Two-in-one strategy: a remineralizing and anti-adhesive coating against demineralized enamel / 国际口腔科学杂志·英文版

Tooth enamel is prone to be attacked by injurious factors, leading to a de/remineralization imbalance. To repair demineralized enamel and prevent pulp inflammation caused by biofilm accumulation, measures are needed to promote remineralization and inhibit bacterial adhesion on the tooth surface. An innovative material, poly (aspartic acid)-polyethylene glycol (PASP-PEG), was designed and synthesized to construct a mineralizing and anti-adhesive surface that could be applied to repair demineralized enamel. A cytotoxicity assay revealed the low cytotoxicity of synthesized PASP-PEG. Adsorption results demonstrated that PASP-PEG possesses a high binding affinity to the hydroxyapatite (HA)/tooth surface. In vitro experiments and scanning electron microscopy (SEM) demonstrated a strong capacity of PASP-PEG to induce in situ remineralization and direct the oriented growth of apatite nanocrystals. Energy dispersive X-ray spectroscopy (EDS), X-ray diffraction analysis (XRD) and Vickers hardness tests demonstrated that minerals induced by PASP-PEG were consistent with healthy enamel in Ca/P ratio, crystal form and surface micro-hardness. Contact angle tests and bacterial adhesion experiments demonstrated that PASP-PEG yielded a strong anti-adhesive effect. In summary, PASP-PEG could achieve dual effects for enamel repair and anti-adhesion of bacteria, thereby widening its application in enamel repair.

Dental remineralization via poly(amido amine) and restorative materials containing calcium phosphate nanoparticles / 国际口腔科学杂志·英文版

Tooth decay is prevalent, and secondary caries causes restoration failures, both of which are related to demineralization. There is an urgent need to develop new therapeutic materials with remineralization functions. This article represents the first review on the cutting edge research of poly(amido amine) (PAMAM) in combination with nanoparticles of amorphous calcium phosphate (NACP). PAMAM was excellent nucleation template, and could absorb calcium (Ca) and phosphate (P) ions via its functional groups to activate remineralization. NACP composite and adhesive showed acid-neutralization and Ca and P ion release capabilities. PAMAM+NACP together showed synergistic effects and produced triple benefits: excellent nucleation templates, superior acid-neutralization, and ions release. Therefore, the PAMAM+NACP strategy possessed much greater remineralization capacity than using PAMAM or NACP alone. PAMAM+NACP achieved dentin remineralization even in an acidic solution without any initial Ca and P ions. Besides, the long-term remineralization capability of PAMAM+NACP was established. After prolonged fluid challenge, the immersed PAMAM with the recharged NACP still induced effective dentin mineral regeneration. Furthermore, the hardness of pre-demineralized dentin was increased back to that of healthy dentin, indicating a complete remineralization. Therefore, the novel PAMAM+NACP approach is promising to provide long-term therapeutic effects including tooth remineralization, hardness increase, and caries-inhibition capabilities.

Oral health in China: from vision to action / 国际口腔科学杂志·英文版

Chinese president Xi Jinping made clear at the National Health and Wellness Conference that health is the prerequisite for people's all-around development and a precondition for the sustainable development of China. Oral health is an indispensable component of overall health in humans. However, the long neglect of oral health in overall health agendas has made oral diseases an increasing concern. With this perspective, we described the global challenges of oral diseases, with an emphasis on the challenges faced by China. We also described and analyzed the recently released health policies of the Chinese government, which aim to guide mid-term and long-term oral health promotion in China. More importantly, we called for specific actions to fulfill the larger goal of oral health for the nation. The implementation of primordial prevention efforts against oral diseases, the integration of oral health into the promotion of overall health, and the management of oral diseases in conjunction with other chronic non-communicable diseases with shared risk factors were highly recommended. In addition, we suggested the reform of standard clinical residency training, the development of domestic manufacturing of dental equipment and materials, the revitalization traditional Chinese medicine for the prevention and treatment of oral diseases, and integration of oral health promotion into the Belt and Road Initiative. We look forward to seeing a joint effort from all aspects of the society to fulfill the goal of Healthy China 2030 and ensure the oral health of the nation.

Clinical management of the intentional tooth replantation / 中华口腔医学杂志

Intentional tooth replantation is the last resort for saving natural teeth in treatment of the endodontic diseases. In order to promote the utilization, standardize the operation and improve the success rate of this treatment, this review suggests the indication, discusses the key points of the surgical procedure, proposes the path of the diagnosis and the treatment protocol of the intentional replantation.

c-di-AMP regulates bacterial biofilm formation / 生物工程学报

Bacterial biofilm plays an important role in persistent microbial infection. Delineation of the formation and development of bacterial biofilm would provide a promising strategy to treat recalcitrant infection. c-di-AMP (Cyclic diadenosine monophosphate) is a recently identified second messenger of bacteria and involved in plethora of bacterial activities, including cell growth, cell wall homeostasis, biofilm formation and microbial pathogenicity. Here we review the recent literature pertinent to the role and molecular mechanisms of c-di-AMP in regulating biofilm formation of bacteria. The potential application of c-di-AMP and its related proteins in the development of novel antimicrobial therapeutics has also been discussed.

Radiographic diagnosis of vertical root fracture / 华西口腔医学杂志

Vertical root fracture (VRF) is different from odontoclasis caused by trauma or injury. VRF is defined as a complete or incomplete fracture of roots caused by long-term and persistent stimulus, such as excessive forces from mastication or occlusion, improper tooth anatomy, and tooth treatment accident. Early diagnosis of VRF is essential to prevent the absorption of alveolar bone, thereby improving prognosis. Radiographic examination is the most common and effective evaluation method for VRF. Cone beam computed tomography can provide three-dimensional information for fracture details, which are more precise than traditional periapical films. In this paper, we present the radiographic features, differential diagnosis, and new treatment techniques for VRF.

Translucency,opalescence and fluorescence properties of six light-cured resin composites / 实用口腔医学杂志

Objective:To evaluate the translucency,opalescence and fluorescence reflection of 6 light-cured resin composites. Methods:Disks of 6 resin composites including Filtek Supreme XT-YT(XT),Filtek Supreme XT-A3B(3M),Clearfil Majesty-A3 (MJ),Gradia Direct-A3(GC),Venus-A3(VE)and Charisma Diamond-A3(CA)were prepared in the diameter of 9 mm with the thickness 2.0 mm.PR-650 spectral scanning colorimeter was used to measure and caculate translucency parameters(TP),opal-escence parameter(OP)and fluorescence reflection(FL)and to draw the fluorescence reflection curves.Results:Except XT and MJ,TP value of other resin composites were in the range of natural tooth.Only OP value of XT was in the range of natural tooth en-amel.FL value of XT was close to that of natural tooth dentin.Fluorescent peak wavelength of GC,MJ,VE and CA were in the range of natural tooth,but fluorescent peak height was higher than that of natual tooth.TP was positively correlated with OP(r =0.85,P <0.05).There was no statistic correlation between TP and FL,between OP and FL.Conclusion:The 6 resin composites can simulate optical property of natual tooth,but the opalescence of resin composites is defective.

Esthetic effect of resin infiltration for the treatment of post-orthodontic white spot lesions / 实用口腔医学杂志

Objective:To evaluate the effects of resin infiltration in the treatment of post-orthodontic white spot lesions (WSLs)and compare it with microabrasion.Methods:1 0 subjects with 66 teeth with noncavitated and unrestored WSLs after multibracket treatment were recruited.A simple randomized,split-mouth and controlled design was used to allocate WSLs to the resin infiltration and micro-abrasion groups(n =33).The area of the WSLs were measured photographically by using image analysis software before treatment (T0),1 week(T2)and 3 months(T3)after treatment.Data were analyzed with multifactorial analysis of the variances with repeated measures at an a level of 5% and a power of 80%.Results:The area of the white spot lesions(R)decreased significantly in both groups(P <0.05).At T3 the success rate of resin infiltration group(88.68%)was significantly higher than that of microabrasion group (64.67%)(P <0.05).Conclusion:Resin infiltration is more effective than microabrasion in the treatment of post-orthodontic WSLs.

Isolation and identification of aerobic and facultative anaerobic bacteria in the oral cavity / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a systematic method for isolation and identification of aerobic and facultative anaerobic bacteria in the oral cavity.</p><p><b>METHODS</b>Samples of the saliva, dental plaque and periapical granulation tissue were collected from 20 subjects with healthy oral condition and from 8 patients with different oral diseases. The bacteria in the samples were identified by morphological identification, VITEK automatic microorganism identification and 16s rRNA gene sequencing.</p><p><b>RESULTS</b>VITEK automatic microorganism identification and 16s rRNA gene sequencing showed an agreement rate of 22.39% in identifying the bacteria in the samples. We identified altogether 63 bacterial genus (175 species), among which Streptococcus, Actinomyces and Staphylococcus were the most common bacterial genus, and Streptococcus anginosus, Actinomyces oris, Streptococcus mutans and Streptococcus mitis were the most common species. Streptococcus anginosus was commonly found in patients with chronic periapical periodontitis. Streptococcus intermedius and Staphylococcus aureus were common in patients with radiation caries, and in patients with rampant caries, Streptococcus mutans was found at considerably higher rate than other species.</p><p><b>CONCLUSION</b>Aerobic and facultative anaerobic bacteria are commonly found in the oral cavity, and most of them are gram-positive. 16s rRNA gene sequencing is more accurate than VITEK automatic microorganism identification in identifying the bacteria.</p>

Effect of arginine dentifrice on remineralization of initial enamel carious lesions / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate remineralization efficacy of an arginine containing dentifrice on initial enamel carious lesions in vitro.</p><p><b>METHODS</b>Human enamel blocks with early lesions were prepared and randomly divided into three treatment groups: negative control group (distilled and deionized water), positive control group (fluoride containing dentifrice and 0.14% sodium monofluorophosphate), and test dentifrice group (8.0% arginine and 0.14% sodium monofluorophosphate). The lesions were subjected to a pH-cycling regime for 10 days. Surface enamel microhardness of the enamel blocks from each group was measured before and after pH cycling, and the surface microhardness recovery was calculated. Then, specimens were analyzed for enamel fluoride uptake (EFU) through acid etching method, after which they were treated in demineralization solution for a 2 h period of acid challenge. The other specimens were sectioned and examined through polarized light microscopy.</p><p><b>RESULTS</b>In the test dentifrice group, microhardness recovery and EFU were significantly higher than those in the negative control and positive groups. The test dentifrice group was significantly resistant to the acid challenge compared with the other groups. Conspicuous remineralization of enamel subsurface lesions was observed under polarized light microscopy among samples treated with test dentifrice, whereas the control groups showed no significant changes on enamel subsurface lesions.</p><p><b>CONCLUSION</b>This study presents the potential superiority of Pro-Argin dentifrice over conventional fluoride dentifrice in promoting the remineralization of initial enamel lesions.</p>

Analysis of EDA gene mutation for a family affected with X-linked hypohidrotic ectodermal dysplasia / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To detect potential mutations of EDA gene for a Chinese family affected with X-linked hypohidrotic ectodermal dysplasia (XLHED).</p><p><b>METHODS</b>Genomic DNA was extracted from peripheral blood of the proband, his relatives and 50 non-related healthy controls. Exonic sequences of the EDA gene were subjected to polymerase chain reaction amplification and direct sequencing.</p><p><b>RESULTS</b>A c.467G> A mutation (R156H) was detected in exon 3 of the EDA gene in the proband, his mother, 2 uncles, and 1 aunt. The same mutation was not detected in the 50 non-related healthy controls.</p><p><b>CONCLUSION</b>A c.467G>A mutation of the EDA gene probably underlies the disease in the family.</p>

The correlation analysis on Enterococcus faecalis biofilm and clinical manifestation in retreatment of root canal / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To detect the ability of Enterococcus faecalis (E. faecalis) biofilm formation and explore the relationship between E. faecalis biofilm formation ability and clinical manifestation.</p><p><b>METHODS</b>96 well plate with the establishment of 53 E. faecalis in vitro biofilm model, combined with crystal violet staining, was used to test the biofilm formation ability of the clinical isolates E. faecalis and analyze the relationship between biofilm formation capacity and clinical manifestation.</p><p><b>RESULTS</b>In total 53 E. faecalis strains, 40 strains(75.47%) had biofilm forming ability. Statistical analysis revealed that the capacities of biofilm formation between E. faecalis isolated from with fistula and without fistula was significantly different (P<0.05).</p><p><b>CONCLUSION</b>In the retreatment of root canal, the ability of biofilm formation of E. faecalis separated from the teeth without fistula is better than those separated from the teeth with fistula.</p>

Study on potential anti-caries DNA vaccine pcDNA3-gtfB integration into host cell genome / 华西口腔医学杂志

<p><b>OBJECTIVE</b>Gene vaccine security is of concern because of the possibility of insertion mutagenesis resulting in inactivation of tumor suppressor or activation of oncogene. The purpose of this study was to examine the potential of anti-caries DNA vaccine pcDNA3-gtfB integrating into the host cell genome.</p><p><b>METHODS</b>Anti-caries DNA vaccine pcDNA3-gtfB was constructed by the previous study. The gtfB gene(904-4,578 bp, genebank M17361) was cloned from Streptococcus mutans GS-5. 36 Wistar rats were divided into 2 groups: submandibular gland-targeted injection(SGT) group and control group. Rats in SGT group were injected with 100 micrograms of plasmid pcDNA3-gtfB, rats in control group with PBS solution. Genomes from submandibular gland, kidney, heart, liver, lung, and brain tissues were isolated later in 12 weeks. Genomes from different tissues were purified by low-melting agarose electrophoresis. Using the purified genomes as template, plasmid integration were examined by PCR(upper primer: 5'-ATATGGTACCATGACCGAAGCGACATCTAAGCAAGA-3', lower primer: 5'-ACTACTCGAGTTAGAACCATTGACCCTG AGCATTGC-3'). The sensitivity level of PCR was determined by adding gradient plasmid copies into genomes in control group.</p><p><b>RESULTS</b>The examination of 6 tissues failed in revealing any evidence of integration at the sensitivity level that could detect 1 copy integration in 10,000 nuclei.</p><p><b>CONCLUSION</b>The potential frequency of plasmid pcDNA3-gtfB integration into host cell genome would not exceed that of the spontaneous mutation. It was indicated that pcDNA3-gtfB was genetically safe as a promising anti-carious DNA vaccine.</p>

Evaluation of the cario-static effect of Nidus vespae on biofilm model in vitro / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the Nidus vespae's cario-static effect on biofilm model in vitro.</p><p><b>METHODS</b>A four-organism bacterial consortium was grown in a biofilm model on hydroxyapatite (HA) discs in a continuous culture system and exposed to repeated solution pulsing respectively. There were three parallel-connected flow cells in the model, so were the three groups with different solution pulsed in. Negative control group was pulsed with distilled water, positive control group was pulsed with 250 mmol/L sucrose solution as well. While 4.0 g/L Nidus vespae together with 250 mmol/L sucrose solution was pulsed in the experiment group. During the experiment, the pH responses against the pulses were recorded. After the 6 pulses, the biofilm surface structure was observed with a scan electron microscope and the population on the biofilm was enumerated.</p><p><b>RESULTS</b>Nidus vespae can significantly inhibit the adherence of Streptococcus mutans to HA discs compared with the control group of 250 mmol/L sucrose pulsed in, and can facilitate the remove of acid products. It is also found that the extra-cellular polysaccharide is reduced with the pulsing of Nidus vespae.</p><p><b>CONCLUSION</b>Nidus vespae in the biofilm model can partially decrease the cariogenic response of sucrose solution pulsed in.</p>

Evaluation of in vitro cario-static effect of Galla chinensis with biofilm model / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the in vitro cario-static effect of Galla chinesis with biofilm model.</p><p><b>METHODS</b>A four-organism bacterial consortium was cultured in a biofilm model on hydroxyapatite (HA) discs in a continuous culture system and exposed to repeated solution pulsing. There were three groups with different solution pulsed in the model: negative control group was pulsed with distilled water, positive control group was pulsed with 100 mmol/L sucrose solution and experimental group was pulsed with 100 mmol/L sucrose solution containing 4.0 g/L Galla chinensis. During the experiment, the dynamic changes of pH were recorded. After 6 pulses, surface structure of the biofilm was observed with a scanning electron microscope and the population on the biofilm was enumerated.</p><p><b>RESULTS</b>Galla chinesis significantly inhibited the adherence of Actinomyces naelundii to HA disc compared with the control group and facilitated the removal of acid products. It was also found that the extra-cellular polysaccharide was reduced with the pulsing of Galla chinesis.</p><p><b>CONCLUSION</b>Galla chinesis in the biofilm model can partially reduce the cario-genic response of sucrose solution.</p>

The effect of para-aminobenzoic acid on growth and metabolism of Porphyromonas gingivalis / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To study the effect of para-aminobenzoic acid (PABA) on the growth and metabolism of Porphyromonas gingivalis (P.g).</p><p><b>METHODS</b>After adding different concentrations of PABA into the medium, anaerobic technique was applied to culture P.g. The products' A value and action of TLP was assayed, and P.g grew in the medium was observed by a scanning electron microscope.</p><p><b>RESULTS</b>PABA promoted the growth of P.g and action of TLP, which would reach the highest level when PABA was 1 mg/L, and would decrease with the increasing of concentration of PABA. When the concentration arrived at 100 mg/L, PABA had no effect on them. In the mean time, PABA had effect on the form and adherence of P.g. When the concentration was 1 mg/L and 100 mg/L, this effect was strong, but as the concentration was 10 mg/L, the effect disappeared.</p><p><b>CONCLUSIONS</b>PABA influences the growth and metabolism of P.g, which indicate that Streptococcus sanguis has regulative effect on the microecology of subgingival plaque.</p>