Clinical application prospects and transformation value of dental follicle stem cells in oral and neurological diseases

Since dental pulp stem cells(DPSCs)were first reported,six types of dental SCs(DSCs)have been isolated and identified.DSCs originating from the craniofacial neural crest exhibit dental-like tissue differentiation potential and neuroectodermal features.As a member of DSCs,dental follicle SCs(DFSCs)are the only cell type obtained at the early developing stage of the tooth prior to eruption.Dental follicle tissue has the distinct advantage of large tissue volume compared with other dental tissues,which is a prerequisite for obtaining a sufficient number of cells to meet the needs of clinical applications.Furthermore,DFSCs exhibit a significantly higher cell proliferation rate,higher colony-formation capacity,and more primitive and better anti-inflammatory effects than other DSCs.In this respect,DFSCs have the potential to be of great clinical significance and translational value in oral and neurological diseases,with natural advantages based on their origin.Lastly,cryopreservation preserves the biological properties of DFSCs and enables them to be used as off-shelf products for clinical applications.This review summarizes and comments on the properties,application potential,and clinical transformation value of DFSCs,thereby inspiring novel perspectives in the future treatment of oral and neurological diseases.

Dental evaluation is helpful in the differentiation of functional heartburn and gastroesophageal reflux disease

BACKGROUND Heartburn is identically the key symptom of both,gastroesophageal reflux disease(GERD)and functional heartburn(FHB),making the differential diagnosis resource-intensive.Oral manifestations of GERD can be easily examined;therefore,their exploration might be a cheap,widely available,and useful tool in the differentiation of GERD and FHB.AIM To evaluate the prevalence of dental erosions(DE)and periodontal diseases(PD)in patients with heartburn and their association with GERD and FHB.METHODS A total of 116[M/F:51/65,mean age:54(17-80)years]consecutive patients with heartburn were enrolled for detailed esophageal function and orodental examinations.RESULTS Dental disorders were detected in 89%(103/116).Patients with PD+DE had significantly more often pathologic reflux(90.0%vs 27.8%;P<0.05),higher esophagitis scores(1.8 vs 0.9;P<0.05),and a significantly different mean impedance curve(P=0.04)than those without any dental diseases.The opposite approach established that patients with GERD had significantly higher prevalence of DE and PD,especially if both were present(28.9%vs 2.0%;P<0.01),more severe PD(1.5 vs 1.0;P<0.01),and longer history of heartburn(15 years vs 9 years;P<0.01)than those with FHB.CONCLUSION The dental evaluation of patients with heartburn seems to be useful in the differential diagnosis of GERD and FHB.Among the studied parameters,the co-appearance of DE and PD seems to be the best predictor of GERD,whereas the absence of dental disorders was mostly observed in FHB.

Dental pulp stem cells for treating neurodegenerative diseases

The hippocampal formation, important for spatial learn- ing and memory function, exhibits high level of plas- ticity in response to behavioral changes as well as injury. Dysfunction of the hippocampus is one of the hallmark features of neurodegenerative diseases like temporal lobe epilepsy （TLE） and Alzheimer＇s disease （AD） （Dhanush- kodi and Shetty 2008）. Excitotoxicity is one of the known mechanisms by which neurons undergo degeneration in neurodegenerative condition （Haglid et al., 1994; Doble et al., 1995）. Brain regions such as hippocampus are more susceptible to excitotoxic damage. During excitotoxicity.

Diagnostic value associated with the combination of saliva pepsin and microorganisms in functional heartburn and gastroesophageal reflux disease

Heartburn is a common symptom shared by both gastroesophageal reflux disease(GERD)and functional heartburn(FHB),which can make it challenging to differentiate between the two conditions.However,examining oral manifestations of GERD can be a cost-effective and readily available method to aid in this differentiation process.It may serve as a valuable tool in distinguishing GERD from FHB.

Regenerative medicine using dental pulp stem cells for liver diseases

Acute liver failure is a refractory disease and its pro-gnosis, if not treated using liver transplantation, is extremely poor. It is a good candidate for regenerative medicine, where stem cell-based therapies play a central role. Mesenchymal stem cells(MSCs) are known to differentiate into multiple cell lineages including hepatocytes. Autologous cell transplant without any foreign gene induction is feasible using MSCs, thereby avoiding possible risks of tumorigenesis and immune rejection. Dental pulp also contains an MSC population that differentiates into hepatocytes. A point worthy of special mention is that dental pulp can be obtained from deciduous teeth during childhood and can be subsequently harvested when necessary after deposition in a tooth bank. MSCs have not only a regenerative capacity but also act in an anti--inflammatory manner via paracrine mechanisms. Promising efficacies and difficulties with the use of MSC derived from teeth are summarized in this review.

Expert System for the Diagnosis and Prognosis of Common Dental Diseases Using Bayes Network

Expert systems are being utilized increasingly in medical fields for the purposes of assisting diagnosis and treatment planning. Existing systems used few symptoms for dental diagnosis. In Dentistry, few symptoms are not enough for diagnosis. In this research, a conditional probability model (Bayes rule) was developed with increased number of symptoms associated with a disease for diagnosis. A test set of recurrent cases was then used to test the diagnostic capacity of the system. The generated diagnosis matched that of the human experts. The system was also tested for its capacity to handle uncommon dental diseases and the system portrayed useful potential.

Immunomodulatory properties of dental tissue-derived mesenchymal stem cells: Implication in disease and tissue regeneration

Mesenchymal stem cells(MSCs)are considered as an attractive tool for tissue regeneration and possess a strong immunomodulatory ability.Dental tissuederived MSCs can be isolated from different sources,such as the dental pulp,periodontal ligament,deciduous teeth,apical papilla,dental follicles and gingiva.According to numerous in vitro studies,the effect of dental MSCs on immune cells might depend on several factors,such as the experimental setting,MSC tissue source and type of immune cell preparation.Most studies have shown that the immunomodulatory activity of dental MSCs is strongly upregulated by activated immune cells.MSCs exert mostly immunosuppressive effects,leading to the dampening of immune cell activation.Thus,the reciprocal interaction between dental MSCs and immune cells represents an elegant mechanism that potentially contributes to tissue homeostasis and inflammatory disease progression.Although the immunomodulatory potential of dental MSCs has been extensively investigated in vitro,its role in vivo remains obscure.A few studies have reported that the MSCs isolated from inflamed dental tissues have a compromised immunomodulatory ability.Moreover,the expression of some immunomodulatory proteins is enhanced in periodontal disease and even shows some correlation with disease severity.MSC-based immunomodulation may play an essential role in the regeneration of different dental tissues.Therefore,immunomodulation-based strategies may be a very promising tool in regenerative dentistry.

Are human dental papilla-derived stem cell and human brain-derived neural stem cell transplantations suitable for treatment of Parkinson’s disease?

Transplantation of neural stem cells has been reported as a possible approach for replacing impaired dopaminergic neurons. In this study, we tested the efficacy of early-stage human dental papilla-derived stem cells and human brain-derived neural stem cells in rat models of 6-hydroxydopamine-induced Parkinson＇s disease. Rats received a unilateral injection of 6-hydroxydopamine into right medial forebrain bundle, followed 3 weeks later by injections of PBS, early-stage human dental papilla-derived stem cells, or human brain-derived neural stem cells into the ipsilateral striatum. All of the rats in the human dental papilla-derived stem cell group died from tumor formation at around 2 weeks following cell transplantation. Postmortem examinations revealed homogeneous malignant tumors in the striatum of the human dental papilla-derived stem cell group. Stepping tests revealed that human brain-derived neural stem cell transplantation did not improve motor dysfunction. In apomorphine-induced rotation tests, neither the human brain-derived neural stem cell group nor the control groups （PBS injection） demonstrated significant changes. Glucose metabolism in the lesioned side of striatum was reduced by human brain-derived neural stem cell transplantation. [18F]-FP-CIT PET scans in the striatum did not demonstrate a significant increase in the human brain-derived neural stem cell group. Tyrosine hydroxylase （dopaminergic neuronal marker） staining and G protein-activated inward rectifier potassium channel 2 （A9 dopaminergic neuronal marker） were positive in the lesioned side of striatum in the human brain-derived neural stem cell group. The use of early-stage human dental papilla-derived stern cells confirmed its tendency to form tumors. Human brain-derived neural stem cells could be partially differentiated into dopaminergic neurons, but they did not secrete dopamine.

Therapeutic potential of dental pulp stem cell transplantation in a rat model of Alzheimer’s disease

Dental pulp stem cells are dental pulp-derived mesenchymal stem cells that originate from the neural crest.They exhibit greater potential for the treatment of nervous system diseases than other types of stem cells because of their neurogenic differentiation capability and their ability to secrete multiple neurotrophic factors.Few studies have reported Alzheimer’s disease treatment using dental pulp stem cells.Rat models of Alzheimer’s disease were established by injecting amyloid-β1–42 into the hippocampus.Fourteen days later,5×106 dental pulp stem cells were injected into the hippocampus.Immunohistochemistry and western blot assays showed that dental pulp stem cell transplantation increased the expression of neuron-related doublecortin,NeuN,and neurofilament 200 in the hippocampus,while the expression of amyloid-βwas decreased.Moreover,cognitive and behavioral abilities were improved.These findings indicate that dental pulp stem cell transplantation in rats can improve cognitive function by regulating the secretion of neuron-related proteins,which indicates a potential therapeutic effect for Alzheimer’s disease.This study was approved by the Animal Ethics Committee of Harbin Medical University,China(approval No.KY2017-132)on February 21,2017.

p75 neurotrophin receptor positive dental pulp stem cells:new hope for patients with neurodegenerative disease and neural injury

Neurodegenerative diseases and neural injury are 2 of the most feared disorders that afflict humankind by leading to permanent paralysis and loss of sensation.Cell based treatment for these diseases had gained special interest in recent years.Previous studies showed that dental pulp stem cells(DPSCs) could differentiate toward functionally active neurons both in vitro and in vivo,and could promote neuranagenesis through both cell-autonomous and paracrine neuroregenerative activities.Some of these neuroregenerative activities were unique to tooth-derived stem cells and superior to bone marrow stromal cells.However,DPSCs used in most of these studies were mixed and unfractionated dental pulp cells that contain several types of cells,and most were fibroblast cells while just contain a small portion of DPSCs.Thus,there might be weaker ability of neuranagenesis and more side effects from the fibroblast cells that cannot differentiate into neural cells.p75 neurotrophin receptor(p75 NTR) positive DPSCs subpopulation was derived from migrating cranial neural crest cells and had been isolated from DPSCs,which had capacity of differentiation into neurons and repairing neural system.In this article,we hypothesize that p75 NTR positive DPSCs simultaneously have greater propensity for neuronal differentiation and fewer side effects from fibroblast,and in vivo transptantation of autologous p75 NTR positive DPSCs is a novel method for neuranagenesis.This will bring great hope to patients with neurodegenerative disease and neural injury.Supported by Key Basic Research Fund of Science and Technology Commission of Shanghai Municipality(10JC1408700).

Periodontal Diseases and Recently Applied Nano-Technology: A Review Article

Nowadays, nano-technology is a promising option for scientists to enhance dental conditions and provide new techniques to offer a more reliable and comfortable therapeutic pickups. In this regard, there are different methods to manufacture novel nano-structured dental materials, and also modern drug delivery techniques. In this review article, all our efforts are based on the recently nano-dental approaches closely linked to treat or prevent some common dental diseases including tooth erosion, tooth sensitivity, periodontal disease, oral cancer, and so on. All the data and articles putted in this survey are gathered from Google Scholar, PubMed, and some dental databases.

New insights in understanding dental caries and periodontal disease: the avalanche model

Biology is based on evolution;therefore, eu-kariotes like plants, animals and human beings are living in harmony with their procariote an-cestors. If this is obviously the normal way of life, then pathobiology follows the same basic principles. The highly complex harmony of the living world may be disrupted, and a punctuated disease starts which is different from the health equilibrium. To reflect this biological archetype on the main diseases in dentistry - caries and periodontitis - the avalanche model is being proposed based on scientific and clinical evi-dence. This way of argumentation does influ-ence the strategic planning of preventive and curative programmes in dental research as well as in daily practise.

Prevalence of Dental Disease and Risk to Oral Health in Oke-Ogun Rural Communities

The importance of oral health and the general health of an individual are interwoven such that if the oral health is poor, the general health would also be poor. There has been an increase in the interest of researchers in the state of the oral health because of the deleterious effects a poor oral health can have on the general health. While the prevalence of oral diseases has been reported to be on the increase worldwide, this paper presents a report on the prevalence of oral diseases in 10 rural communities known as Oke-ogun communities in Oyo State of Nigeria. Cleft and Facial Deformity Foundation (CFDF), an indigenous non-governmental organization (NGO) organized an outreach program, with permission from the State Health Ministry, to examine, diagnose dental diseases, and carry out free surgeries for patients in the visited communities. The program was for two weeks and was divided in phases with the first phase done in May 2019 and second phase in September 2019. Among 1396 respondents, 43.6% complained of toothaches with more female than male presenting with that complain. Also, 511 (36.6%) were reported to have gingivitis and 51 (3.7%) had dental caries. Furthermore, gingivitis and chronic periodontitis were more common in males 776 (55.6%) than females 620 (44.4%) and this was statistically significant at ≤0.002. Periodontal disease was found to be more prevalent in Oke-ogun communities in Oyo state, and this called for urgent intervention strategies by the federal government of Nigeria, non-governmental organizations (NGO) and the international organizations like the World Health Organization (WHO) since the poor oral health would eventually translate to poor general health.

Antibacterial Effect of Aqueous Extracts and Bioactive Chemical Compounds of <i>Coffea canephora</i>against Microorganisms Involved in Dental Caries and Periodontal Disease

This study aimed to evaluate the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of Coffea canephora aqueous extract (Cc), trigonelline (Tg) and 5-caffeoylquinic acid (5-CQA) against cariogenic microorganisms: Streptococcus parasanguinis ATCC 903 (SP), Lactobacillus rhamnosus ATCC 9595 (LR);and pathogens related to periodontal disease: Porphyromonas gingivalis ATCC 33277 (PG), Fusobacterium nucleatum ATCC 25586 (FN), Prevotella intermedia ATCC 49046 (PI) and Prevotella nigrescens ATCC 33563 (PN). Different concentrations of Cc (0.15625 to 10 mg/mL), Tg and 5-CQA (0.005 to 10.24 mg/mL) were tested. Chlorhexidine (0.05%) was used as positive control and the substances without the inoculum comprised the blank control. The Cc showed bacteriostatic action against SP (MIC = 5 mg/mL) and LR (MIC = 10 mg/mL). Tg showed bacteriostatic action against SP (MIC = 2.56 to 1.28 mg/mL), LR (MIC = 2.56 mg/mL), PG (MIC = 2.56 to 1.28 mg/mL), FN (MIC = 5.12 mg/mL), PN (MIC = 2.56 mg/mL), and PI (MIC = 2.56 to 1.28 mg/mL). Also, Tg showed bactericide properties against SP (MBC = 2.56 mg/mL), PG (MBC = 2.56 mg/mL), FN (MBC = 10.24 mg/mL), PN (MBC = 5.12 mg/mL), and PI (MBC = 2.56 mg/mL). Although 5-CQA has previously shown activity against Streptococcus mutans, in the present study, it showed no activity against all tested microorganisms. C. canephora extract only showed antibacterial activity against cariogenic microorganisms, not presenting action against periodontal pathogens. It was concluded that trigonelline presented the best effect against all pathogens tested, therefore coffee extracts with higher trigonelline content should be tested against these specific pathogens.

Two Cases of Parkinson’s Disease for Which Dental Treatment Was Effective

The purpose of this study is to document the improvement observed in two cases of Parkinson’s disease (PD) after dental treatment. The first subject is a man in his 60s with severe Parkinson’s disease;medication has not been very effective in this case. Prior to treatment, he was unable to stand without support due to?rigidity. Just after removing as much of the dental infection as possible, he was able to walk, albeit slowly, and as a result of continuing treatment, one month later, the symptoms had significantly improved. The second subject?is a woman in her 40s, who became aware of joint stiffness seven years ago, and was later diagnosed with PD independently at three hospitals. Her main symptoms were rigidity, knee pain, and speech disorder. The dopamine medication worked well against rigidity, but the symptoms reappeared after the medication stopped working. Her condition was significantly improved just after one tooth with an apical lesion was extracted. Although the underlying mechanism has not been clarified, I hypothesize that, at least in these cases, negative signals that passed through the trigeminal nerve to the midbrain affected predominantly the dopaminergic neurons in the substantia nigra of the midbrain. Removal of the harmful signals from the oral area resulted in normalization of the substantia nigra. Further research should be promoted with dental and medical cooperation.

Assessment of Knowledge of the Relationship between Periodontal Disease and Systemic Disease among Dental Students and Its Impact on Oral Hygiene Practices

Background: Dental students play a role in both oral and general health education in their communities, so it is important that they have good knowledge to enable them offer good counsel. Knowing the relationship between periodontal disease and systemic conditions will put them in better stead when giving oral health education. The aim of this study was to assess the level of knowledge among dental students of the relationship between periodontal diseases and systemic conditions, and to determine whether there was a correlation between this knowledge and their oral hygiene practices. Methods: This was a cross-sectional study among dental students of the University of Port Harcourt, Rivers State, Nigeria. Consenting participants were given a self-administered questionnaire eliciting socio-demographic information, knowledge about the relationship between periodontal diseases and systemic diseases, as well as oral hygiene practices. Each correct response on knowledge was scored as 1, while incorrect responses were scored 0, with a maximum score of 7. Participants’ knowledge was graded as poor (0 - 2), fair (3 - 5) and good (6 - 7). Data was analyzed using IBM SPSS version 21. p ≤ 0.05 was considered statistically significant. Spearman’s ranked correlation was used to assess the correlation between knowledge of the relationship between periodontal diseases and systemic diseases and oral hygiene practices. Results: There were 109 dental students (58 males, 51 females) in this study, with a mean age of 24.1 ± 3.6 years. Preclinical students were 43 (39.4%) while clinical students were 66 (60.6%). All (100%) participants knew that oral health was important to systemic health, with 89.9% knowing that periodontal disease was specifically linked to systemic disease. Only 50.5% of participants knew that there was a link between periodontal disease and diabetes mellitus. Sixty-four (58.7%) of the participants regularly cleaned in between their teeth. The most commonly used interdental cleaning aid was toothpick (45.0%). Clinical students had significantly better knowledge on the relationship between periodontal disease and systemic disease compared to pre-clinical students (p = 0.001). There was positive correlation between knowledge about periodontal disease and its link with systemic disease and better oral hygiene practices, but this was not statistically significant. Conclusion: The majority of dental students had a fair knowledge about the relationship between periodontal diseases and systemic diseases.

计算机辅助设计三维牙颌分割及应用场景

背景:传统的三维牙颌模型分割方法通常利用预定义的空间几何特征如曲率、法向量等作为牙齿分割的参考信息。目的:提出一种适用于复杂三维牙颌分割的算法并深度挖掘分割结果与应用场景之间的关联性。方法:建立基于结构特征和空间特征双流提取的三维牙颌分割算法,利用分流的模块化设计避免特征混淆。其中,结构特征流上的注意力机制用于捕获牙齿分割所需的细粒度语义信息,空间特征流上的Tran-Net用于保证模型对复杂牙颌分割的鲁棒性。该算法在包含健康牙颌和缺牙、错牙、牙列拥挤等复杂牙颌的临床数据集上验证有效性和可靠性,通过总体精度、均交并比、方向切割差异等评价指标衡量模型的分割性能。结果与结论:该算法在临床数据集上的总体分割精度为97.08%,分割效果从定性和定量的角度均优于其他竞争方法。验证了此次设计的结构特征流,通过构建注意力聚合机制从坐标和法向信息中可提取更精细齿形局部细节,设计的空间特征流通过构建变换网络(Tran-Net)可保证模型对缺牙、错牙、牙列拥挤等复杂牙颌的鲁棒性。因此,该牙齿分割算法对于临床医生实操参考具有较强的可靠性。

牙体牙髓病根管治疗应用iRoot SP冷侧法的效果

目的探讨牙体牙髓病根管治疗应用iRoot SP冷侧法的效果。方法筛选2018-06至2020-06在解放军总医院京南医疗区就诊的牙体牙髓病患者100例,随机分为对照组和试验组,每组50例,均进行根管治疗,其中对照组充填根管采用热牙胶垂直加压法,试验组采用iRoot SP冷侧法。比较两组根管充填效果、临床总有效率、疼痛视觉模拟评分(VAS)及咀嚼功能。结果两组治疗后根管充填效果和临床总有效率比较,差异无统计学意义(P>0.05);试验组治疗后1周[(4.13±0.79)vs.(5.11±0.98)]及1个月[(2.45±0.37)vs.(3.11±0.67)]VAS评分低于对照组,治疗后咬合力[(131.25±11.21)lbs vs.(120.34±14.09)lbs]及咀嚼效率[(90.12±4.13)%vs.(78.98±7.45)%]均优于对照组,差异均有统计学意义(P<0.05)。结论根管治疗牙体牙髓病中应用iRoot SP冷侧法的充填效果和疗效与热牙胶垂直加压法基本相同,但iRoot SP冷侧法在减轻患者疼痛,改善咀嚼功能方面更具优势。

牙体牙髓病患者根管治疗后口腔健康行为状况分析

目的 分析牙体牙髓病患者根管治疗后口腔健康行为状况。方法 选择2022年4月至10月新疆医科大学第一附属医院拟行根管治疗的100例牙体牙髓病患者,所有患者均在根管治疗后2周首次复查时采用自制的口腔健康行为状况量表评估口腔健康行为状况,分析牙体牙髓病患者根管治疗后口腔健康行为状况。结果 100例牙体牙髓病患者根管治疗后口腔健康行为状况得分为(76.18±5.46)分。不同年龄、受教育程度、吸烟、心理状态低下、营养状态患者治疗后口腔健康行为状况得分比较,差异有统计学意义(P<0.05)。年龄≥60岁、初中及以下、吸烟、存在营养不良风险或营养不良是牙体牙髓病根管治疗后口腔健康行为状况的影响因素(P<0.05);线性方程为Y=71.636+3.127X_(1)+3.975X_(2)+4.550X_(3)-6.762X_(4)。结论 牙体牙髓病患者根管治疗后口腔健康行为状况处于中等偏上水平,且患者口腔健康行为状况受年龄、受教育程度、吸烟、营养状态等因素影响。

龋病患儿唾液离子浓度、链球菌、双歧杆菌变化与病情的关联性研究

目的:分析龋病患儿唾液离子浓度、链球菌、双歧杆菌变化与病情的关联性。方法:选择2022年5月—2023年4月收治的80例3~6岁龋病患儿为试验组,根据龋失补指数(DMFT)分为轻度组(DMFT≤15%,n=35)和重度组(DMFT>15%,n=45);另选择进行健康检查的80例3~6岁无龋病患儿为对照组。采用甲基麝香酚蓝检测唾液中钙离子浓度,采用实时定量PCR技术检测链球菌、双歧杆菌水平,采用Pearson分析DMFT与唾液钙离子浓度、链球菌、双歧杆菌的相关性,并采用受试者工作特征曲线(receiver operating characteristic curve,ROC)评估唾液钙离子浓度、链球菌、双歧杆菌对龋病患儿病情严重程度的诊断价值,计算曲线下面积(area under the curve,AUC)。采用SPSS 22.0软件包对数据进行统计学分析。结果:试验组唾液钙离子浓度、变形链球菌、远缘链球菌和双歧杆菌水平显著高于对照组(P<0.05);重度组显著高于轻度组(P<0.05);DMFT与唾液钙离子浓度、链球菌、双歧杆菌呈正相关(P<0.05)。根据DMFT制作ROC曲线,唾液钙离子浓度、变形链球菌、远缘链球菌和双歧杆菌对评估龋病患儿病情严重程度的AUC分别为0.760、0.658、0.718和0.705。结论:唾液离子浓度、变形链球菌、远缘链球菌和双歧杆菌水平增加与患儿龋病有关,与龋病病情程度呈正相关,对评估病情严重程度有一定价值。