Background: Electronic cigarette (e-cigs) smoking is substitutional to traditional cigarette smoking to reduce the dangerous combustion of products. Moreover, passive smoking is involuntarily tobacco smoking due to th...Background: Electronic cigarette (e-cigs) smoking is substitutional to traditional cigarette smoking to reduce the dangerous combustion of products. Moreover, passive smoking is involuntarily tobacco smoking due to the exposure to cigarette or tobacco smoke among non-smokers and due to there being little knowledge about the impact of passive e-cigs smoking on periodontal status and salivary pH. Therefore, the present study aimed to evaluate the effect of e-cigs smoking habit on periodontal tissue and salivary pH among some passive e-cigs smokers referred to the college of dentistry clinics, King Khalid University. Material and Methods: Ninety male participants who were referred to the college of dentistry clinics at King Khalid University were included in the study. Age, gender, e-cigs smoking, and general health were recorded. The participants were divided into three equal groups (n = 30) as follows: Group I (Non-passive e-cigs smokers and non-smokers) as the control group, Group II (e-cigs users), and Group III (Passive e-cigs smokers). Salivary pH, plaque control record (PCR), gingival bleeding index (GBI), clinical attachment loss (CAL), percentage of radiographic bone loss (% RBL), periodontal pocket depth (PPD), more than 5 missing teeth due to periodontal diseases (>5 MTDP), tooth mobility (TM), furcation involvement (FI), Bite collapse (BC), and less than 20 remaining teeth (10 Opposing pairs) (L20RT) as well as HbA1c were recorded. ANOVA test was used to the comparison between Groups I, II, and III in the participants’ ages and periodontitis staging clinical findings. The mean of participants’ age groups, the mean of salivary pH values of study groups, and the periodontitis staging complexity and HbA1c were compared between groups with the ANOVA test, Tukey’s test, and the chi-square test. P-value was recorded, and less than 0.5 was considered a statistically significant difference (p Results: The e-cigs users group revealed higher means of PCR, GBI %RBL values, and the participants percentages of >5 MTDP, TM, FI, L20RT, and diabetes mellitus (DM) among participants compared to the passive e-cigs smokers group and control group except for the participants percentage of BC among the participants, which was higher among the control group participants. The differences were not significant in PCR, GBI, %RBL and DM (p > 0.5) and significant in >5 MTDP, TM, FI, L20RT and smoking (p 7% values compared to the e-cigs users group and control group participants. The differences were not significant in CAL and PPD (p > 0.5) and significant in the participants percentages of salivary pH values (p Conclusion: The e-cigs smoking habit was the cause of an increase in periodontal disease severity among the electronic smokers rather than passive e-cigs smokers, although the salivary pH was higher in the latter.展开更多
The aim of the present study was to assess the dietary habits and oral hygiene practice of dental students in a new dental school. A self-administered structured closed-ended questionnaire on demographic characteristi...The aim of the present study was to assess the dietary habits and oral hygiene practice of dental students in a new dental school. A self-administered structured closed-ended questionnaire on demographic characteristics, medical history, oral hygiene and dietary habits was distributed to dental students. Results showed that One third of students indicated that they don’t consume low pH beverages (soft drinks) at all, while 48.9% drink a soft drink or two a day. Students took varying amount of time to consume their drinks. The majority of participants consumed citric juices, fruits and/or pickles at least once a day. 91.3% of students use either soft (41.8%) or medium (49.5%) toothbrush. Only a fifth (16.9%) of the students brush their teeth after drinking soft drinks and 58.2% brush their teeth after vomiting. In conclusion, young adults need to be aware about their dietary habits & oral hygiene, and also a proper dental health program needs to be applied.展开更多
BACKGROUND Accreditation processes are extensively employed to guarantee the quality of higher education institutions.However,this process can potentially generate a stressful atmosphere for staff,thus impacting their...BACKGROUND Accreditation processes are extensively employed to guarantee the quality of higher education institutions.However,this process can potentially generate a stressful atmosphere for staff,thus impacting their ability to perform optimally under pressure.AIM To examine the knowledge of the National Commission for Academic Assessment and Accreditation(NCAAA)and its effects on perceived stress among dental college staff before and after the program accreditation process.METHODS The present cross-sectional questionnaire-based study included 300 employees from three dental colleges.The same employees had to fill out the questionnaire 1 mo after the NCAAA process.RESULTS Approximately 51.33%of the included employees believed that NCAAA is essential to attract quality students to join the program before and after the program.A total of 44.67%felt that their stress was high before,and 31.33%had low stress levels before and after NCAAA.These findings were statistically significant(P≤0.05).CONCLUSION NCAAA raised the prestige of the institution and specific programmes and increased prospects to attract better students,staff,and money,according to the employees.In addition to their needed teaching,research,and other service responsibilities,this work requires a tremendous amount of faculty effort and may cause them stress.展开更多
Tooth enamel is a complex mineralized tissue consisting of long and parallel apatite crystals configured into decussating enamel rods. In recent years, multiple approaches have been introduced to generate or regenerat...Tooth enamel is a complex mineralized tissue consisting of long and parallel apatite crystals configured into decussating enamel rods. In recent years, multiple approaches have been introduced to generate or regenerate this highly attractive biomaterial characterized by great mechanical strength paired with relative resilience and tissue compatibility. In the present review, we discuss five pathways toward enamel tissue engineering,(i) enamel synthesis using physico-chemical means,(ii) protein matrix-guided enamel crystal growth,(iii) enamel surface remineralization,(iv) cell-based enamel engineering, and(v) biological enamel regeneration based on de novo induction of tooth morphogenesis. So far, physical synthesis approaches using extreme environmental conditions such as pH, heat and pressure have resulted in the formation of enamel-like crystal assemblies.Biochemical methods relying on enamel proteins as templating matrices have aided the growth of elongated calcium phosphate crystals. To illustrate the validity of this biochemical approach we have successfully grown enamel-like apatite crystals organized into decussating enamel rods using an organic enamel protein matrix. Other studies reviewed here have employed amelogeninderived peptides or self-assembling dendrimers to re-mineralize mineral-depleted white lesions on tooth surfaces. So far, cell-based enamel tissue engineering has been hampered by the limitations of presently existing ameloblast cell lines. Going forward, these limitations may be overcome by new cell culture technologies. Finally, whole-tooth regeneration through reactivation of the signaling pathways triggered during natural enamel development represents a biological avenue toward faithful enamel regeneration. In the present review we have summarized the state of the art in enamel tissue engineering and provided novel insights into future opportunities to regenerate this arguably most fascinating of all dental tissues.展开更多
The aim of this article was to analyze the theories underpinning dental fear, anxiety and phobias. To be included, articles must have been published between the years of 1949 and 2013 concerning fears and phobias with...The aim of this article was to analyze the theories underpinning dental fear, anxiety and phobias. To be included, articles must have been published between the years of 1949 and 2013 concerning fears and phobias within dentistry and/or psychiatry. Of 200 articles originally under review, 140 were included and reviewed by the authors.Five specific pathways relating to dental fear and anxiety were identified; Cognitive Conditioning, Informative, Visual Vicarious, Verbal Threat, and Parental. Eight currently accepted management techniques across all dental disciplines for dental fear and anxiety were identified. Further research is required to identify clinical diagnosis and treatment for fears originating from different pathways.展开更多
BACKGROUND Basal cell carcinoma(BCC)is a slow-growing malignant tumor characterized by local invasiveness but an exceptionally rare metastatic potential.It ideally affects sun-exposed skin of older patients with more ...BACKGROUND Basal cell carcinoma(BCC)is a slow-growing malignant tumor characterized by local invasiveness but an exceptionally rare metastatic potential.It ideally affects sun-exposed skin of older patients with more propensity for the facial region.AIM To evaluate the different clinicopathological characteristics of the facial BCC and the efficacy and safety of diode laser for the treatment of these lesions.METHODS We retrospectively reviewed facial BCC lesions of<1.5 cm in diameter and subjected them to diode laser ablation during the period from September 2016 to August 2021 at Al-Ramadi Teaching Hospital,Ramadi City,Iraq.Data matching the age,gender,duration,site,and clinical and histological types were registered for every subject.The functional and aesthetic outcomes and complications following diode laser ablation for each patient were also recorded.RESULTS Of 67 patients with facial BCC,there was 65.67%from the age group≥60 years and 58.21%males.The mean duration of the lesions was 5.15±1.836 mo.The most involved location was the nose(29.85%).About half of the cases belong to the noduloulcerative type.Solid histological type comprises 40.3%of the cases,while the least was keratotic(13.4%).Moreover,65.2%of the solid cases were from the age group≤60 years and 38.6%of the adenoid type from the age group>60 years(P value=0.007).Excellent aesthetic and functional outcomes were reported in all cases after 6 mo of follow-up.Few complications were reported after diode laser ablation.CONCLUSION Facial BCC was mostly seen in the elderly and men.The mean duration was 5.15 mo.The nose was the commonest involved site.Noduloulcerative lesions were seen in approximately half of the lesions.The age of the patients determined the histological type of the lesion(solid type was mostly seen in the age group≤60 years,while,adenoid in the age group>60 years).Diode laser ablation showed excellent functional and aesthetic outcomes following a 6-mo follow-up.展开更多
BACKGROUND The use of advanced platelet-rich fibrin(A-PRF)membranes for guided bone and tissue regeneration in through-and-through defects after endodontic surgery was explored in three cases.CASE SUMMARY Herein,three...BACKGROUND The use of advanced platelet-rich fibrin(A-PRF)membranes for guided bone and tissue regeneration in through-and-through defects after endodontic surgery was explored in three cases.CASE SUMMARY Herein,three patients presented to the endodontic clinic suffering from apical periodontitis,associated with large bone resorption and related to previously endodontically treated teeth.Periapical surgery was indicated in these cases and the osteotomy site was covered by A-PRF membrane.Cone-beam computed tomography(CBCT)was used to assess the cases before and after the surgery.CONCLUSION Four months post-surgery,the recall CBCT scan showed complete obliteration of the osteotomy with newly formed bone.A-PRF membrane showed promising results and was an advantageous addition to surgical endodontic treatment.展开更多
Cancer is a disease that is rapidly expanding in prevalence all over the world.Cancer cells canmetastasize,or spread,across the body and impact several different cell types.Additionally,the incidence rates of several ...Cancer is a disease that is rapidly expanding in prevalence all over the world.Cancer cells canmetastasize,or spread,across the body and impact several different cell types.Additionally,the incidence rates of several subtypes of cancer have been on the rise in India.The countermeasures for the cancer disease can be taken by determining the specific expansion rate of each type.To rank the various forms of cancer’s rate of progression,we used some of the available data.Numerous studies are available in the literature which show the growth rate of cancer by different techniques.The accuracy of the scheme in determining the highest growth rate may vary due to the variation in the dependent factors.Within the context of this research,the Fuzzy triangular technique for order preference by similarity to ideal solution(TOPSIS),is utilized to rank the various categorizations of cancer with the help of four groups of medical professionals acting in the capacity of decision-makers.The number of decision-makers may variate according to the required accuracy of results.The findings of the three-dimensional Fuzzy TOPSIS analysis categorize each variety of cancer according to the rate at which it spreads over time.Numerical results along with visual representation are presented to examine the efficiency of our proposed work.展开更多
Indian medicinal plants are referred to as the“nectar of life”owing to their phytochemicals and bioactive complexes that are beneficial in treating diseases.Coronavirus disease 2019(COVID-19)is a global health issue...Indian medicinal plants are referred to as the“nectar of life”owing to their phytochemicals and bioactive complexes that are beneficial in treating diseases.Coronavirus disease 2019(COVID-19)is a global health issue without any proper medication.The indigenous plants of India can be exploited to control the precise signs of SARS-CoV-2.The Ministry of AYUSH(Ayurveda,Yoga and Naturopathy,Unani,Siddha,and Homeopathy)has advised routine usage of medicinal plants for COVID-19.Medicinal plants like Zingiber officinalis,Azadirachta indica,Ocimum sanctum,Nigella sativa,Withania somnifera,Curcuma longa,Piper nigrum,Allium sativum,Tinospora cordifolia,etc.have immunity-boosting,antiviral,antibacterial,antioxidant and anti-inflammatory actions that can suppress and treat symptoms of COVID-19.In vitro,in vivo as well as in silico validation,these phytochemicals can help us to manage and treat COVID-19 disease.This integration of traditional knowledge in the prophylaxis of corona infection and current skills validating it for the development of precise and powerful therapeutic approaches will more efficiently resolve different clinical aspects of COVID-19.The review focuses on both traditional and emergent methods to prevent and treat COVID-19 with various Indian medicinal plants along with their phytochemicals.展开更多
Objective: To assess the actual practical attitude and knowledge of dental implants among senior dental students and general dentists graduated from some Saudi and Non-Saudi dental schools. Methods: A total of 300 sen...Objective: To assess the actual practical attitude and knowledge of dental implants among senior dental students and general dentists graduated from some Saudi and Non-Saudi dental schools. Methods: A total of 300 senior dental students and general dentists participated in the study. Hard copies of the self-designed, multiple-choice questionnaires were distributed to all participants. The questionnaire consisted of 31 questions in five parts. Data were collected and analyzed using Chi-square test and t-test, where p Results: There is a statistically significant relationship between the participants’ answers, and their dental schools. Participants’ general knowledge, training, and teaching of dental implants, as well as information about restorations retained for the dental implants, were higher among participants from Saudi dental schools than participants from non-Saudi dental schools, while the information about dental implants was higher among participants from non-Saudi dental schools than participants from Saudi dental schools. Conclusion: We conclude that the actual practical attitude and knowledge of dental implants among participants in the current study was insufficient. Therefore, dental implant education in the undergraduate curricula of dental schools surveyed should be updated to include teaching, laboratory training, and preclinical and clinical training.展开更多
Objective: To assess daily lifestyle habits as risk factors for plaque-induced gingivitis and periodontitis severity and grading among samples of dental students at King Khalid University. Material and Methods: This s...Objective: To assess daily lifestyle habits as risk factors for plaque-induced gingivitis and periodontitis severity and grading among samples of dental students at King Khalid University. Material and Methods: This study included 150 male participants. They were divided according to the levels into three equal groups: levels 5, 6, and 7 (group I), levels 8, 9, 10 (group II) and levels 11, 12, and interns (group III). This study consisted of questions related to age, gender, educational level, father’s education, mother’s education, home ownership, brushing teeth more than or twice a day, in addition to daily lifestyle habits that were daily smoking, daily use of sugary drinks, and daily use of sugary foods. Some clinical parameters of plaque-induced gingivitis and periodontitis and the percentage of radiographic bone loss were recorded. All data were collected and analyzed using Tukey’s test and Chi-square test. A P-value of less than 0.5 (p Results: One hundred fifty male dental students of different levels in the college of dentistry at King Khalid University participated in the study in three groups (I, II, and III). The mean age of group III is more than that of group II and group I, with highly statistically significant differences (p 30%) were more among the participants in group I than the participants in groups III and II. There was an increase in the percentage of affected participants with stages III and IV of clinical attachment loss (CAL), periodontal pocket depth (PPD), radiographic bone loss (%RBL), tooth mobility, as well as glycated hemoglobin (HbA1c) test values (>7%), and the number of cigarettes smoked per day (>10 cigs) in group III more than in group II and I. Conclusion: We conclude that the severity and grading of plaque-induced gingivitis were higher among the participants in group I, while the severity and grading of periodontitis were higher among the participants in group III due to the different impact of their daily lifestyle habits.展开更多
Skeletal stem and progenitor cells(SSPCs) perform bone maintenance and repair. With age, they produce fewer osteoblasts and more adipocytes leading to a loss of skeletal integrity. The molecular mechanisms that underl...Skeletal stem and progenitor cells(SSPCs) perform bone maintenance and repair. With age, they produce fewer osteoblasts and more adipocytes leading to a loss of skeletal integrity. The molecular mechanisms that underlie this detrimental transformation are largely unknown. Single-cell RNA sequencing revealed that Notch signaling becomes elevated in SSPCs during aging. To examine the role of increased Notch activity, we deleted Nicastrin, an essential Notch pathway component, in SSPCs in vivo. Middle-aged conditional knockout mice displayed elevated SSPC osteo-lineage gene expression, increased trabecular bone mass, reduced bone marrow adiposity, and enhanced bone repair. Thus, Notch regulates SSPC cell fate decisions, and moderating Notch signaling ameliorates the skeletal aging phenotype, increasing bone mass even beyond that of young mice. Finally, we identified the transcription factor Ebf3 as a downstream mediator of Notch signaling in SSPCs that is dysregulated with aging, highlighting it as a promising therapeutic target to rejuvenate the aged skeleton.展开更多
Periodontal disease has been recently linked to a variety of systemic conditions such as diabetes, cardio-vascular disease, preterm delivery, and oral cancer. The most common bacteria associated with periodontal disea...Periodontal disease has been recently linked to a variety of systemic conditions such as diabetes, cardio-vascular disease, preterm delivery, and oral cancer. The most common bacteria associated with periodontal disease, Porphyromonas gingivalis (P. gingivalis) has not yet been studied in the malignant gingival tissues. The objective of this study was to investigate the presence of P. gingivalis in specimens from squamous cell carcinoma patients. We have performed immunohistochemical staining to investigate the presence of P. gingivalis and Streptococcus gordonii (S. gordonii), a non invasive oral bacteria, in paraffin embedded samples of gingival squamous cell carcinoma (n=10) and normal gingiva (n=5). Staining for P. gingivalis revealed the presence of the bacteria in normal gingival tissues and gingival carcinoma, with higher levels (more than 33%, P<0.05) detected in the carcinoma samples. The staining intensity was also significantly enhanced in the malignant tissue by 2 folds (P<0.023) compared to specimens stained for the non-invasive S. gordonii. P. gingivalis is abundantly present in malignant oral epithelium suggesting a potential association of the bacteria with gingival squamous cell carcinoma.展开更多
Formation of the periodontium begins following onset of tooth-root formation in a coordinated manner after birth. Dental follicle progenitor cells are thought to form the cementum, alveolar bone and Sharpey's fibe...Formation of the periodontium begins following onset of tooth-root formation in a coordinated manner after birth. Dental follicle progenitor cells are thought to form the cementum, alveolar bone and Sharpey's fibers of the periodontal ligament (PDL). However, little is known about the regulatory morphogens that control differentiation and function of these progenitor cells, as well as the progenitor cells involved in crown and root formation. We investigated the role of bone morphogenetic protein-2 (Bmp2) in these processes by the conditional removal of the Bmp2 gene using the Sp7-Cre-EGFP mouse model. Sp7-Cre-EGFP first becomes active at E18 in the first molar, with robust Cre activity at postnatal day 0 (P0), followed by Cre activity in the second molar, which occurs after P0. There is robust Cre activity in the periodontium and third molars by 2 weeks of age. When the Bmp2 gene is removed from Sp7+ (Osterix+) cells, major defects are noted in root, cellular cementum and periodontium formation. First, there are major cell autonomous defects in root-odontoblast terminal differentiation. Second, there are major alterations in formation of the PDLs and cellular cementum, correlated with decreased nuclear factor IC (Nfic), periostin and α-SMA+ cells. Third, there is a failure to produce vascular endothelial growth factor A (VEGF-A) in the periodontium and the pulp leading to decreased formation of the microvascular and associated candidate stem cells in the Bmp2-cKOSp7-Cre-EGFP . Fourth, ameloblast function and enamel formation are indirectly altered in the Bmp2-cKOSp7-Cre-EGFP . These data demonstrate that the Bmp2 gene has complex roles in postnatal tooth development and periodontium formation.展开更多
Bone morphogenetic proteins(BMPs) have multiple roles in skeletal development, homeostasis and regeneration. BMPs signal via type I and type II serine/threonine kinase receptors(BMPRI and BMPRII). In recent decades, g...Bone morphogenetic proteins(BMPs) have multiple roles in skeletal development, homeostasis and regeneration. BMPs signal via type I and type II serine/threonine kinase receptors(BMPRI and BMPRII). In recent decades, genetic studies in humans and mice have demonstrated that perturbations in BMP signaling via BMPRI resulted in various diseases in bone, cartilage, and muscles. In this review, we focus on all three types of BMPRI, which consist of activin-like kinase 2(ALK2, also called type IA activin receptor), activinlike kinase 3(ALK3, also called BMPRIA), and activin-like kinase 6(ALK6, also called BMPRIB). The research areas covered include the current progress regarding the roles of these receptors during myogenesis,chondrogenesis, and osteogenesis. Understanding the physiological and pathological functions of these receptors at the cellular and molecular levels will advance drug development and tissue regeneration for treating musculoskeletal diseases and bone defects in the future.展开更多
Helicobacter pylori(H.pylori)infection is one of the most common bacterial infections in humans.Although H.pylori may be detected in the stomach of approximately half of the world’s population,the mechanisms of trans...Helicobacter pylori(H.pylori)infection is one of the most common bacterial infections in humans.Although H.pylori may be detected in the stomach of approximately half of the world’s population,the mechanisms of transmission of the microorganism from individual to individual are not yet clear.Transmission of H.pylori could occur through iatrogenic,fecal-oral,and oral-oral routes,and through food and water.The microorganism may be transmitted orally and has been detected in dental plaque and saliva.However,the role of the oral cavity in the transmission and recurrence of H.pylori infection has been the subject of debate.A large number of studies investigating the role of oral hygiene and periodontal disease in H.pylori infection have varied significantly in terms of their methodology and sample population,resulting in a wide variation in the reported results.Nevertheless,recent studies have not only shown that the microorganism can be detected fairly consistently from the oral cavity but also demonstrated that the chances of recurrence of H.pylori infection is more likely among patients who harbor the organism in the oral cavity.Furthermore,initial results from clinical trials have shown that H.pylori-positive dyspeptic patients may benefit from periodontal therapy.This paper attempts to review the current body of evidence regarding the role of dental plaque,saliva,and periodontal disease in H.pylori infection.展开更多
BACKGROUND Contemporary innovations in the area of local anesthesia have attempted to provide an absolutely pain free experience for patients.Since the introduction of Computer-Controlled Local Anesthetic Delivery Sys...BACKGROUND Contemporary innovations in the area of local anesthesia have attempted to provide an absolutely pain free experience for patients.Since the introduction of Computer-Controlled Local Anesthetic Delivery Systems to dentistry,many studies have compared its efficacy and safety to conventional anesthesia.However,very few studies have compared single tooth anesthesia(STA)and traditional local anesthesia.AIM To compare pain rating,changes in blood pressure,and heart rate during the local anesthetic injection.The secondary objectives were to measure the patients’level of satisfaction and the differences in anesthetic efficiency between the STA system and traditional local infiltration.METHODS A randomized controlled trial was conducted and a total of 80 patients with dental restorative needs were enrolled for the study.The patients were evaluated for their general physical status and oral clinical findings before enrollment.Information regarding perceived pain,changes in heart rate and blood pressure,and patients’satisfaction was collected using an electronic data form and was analyzed using paired and unpaired t-tests.RESULTS No significant difference was noted in perceived pain(P=0.59)and systolic blood pressure(P=0.09)during anesthetic injection using both traditional and STA techniques.STA patients had a significantly higher heart rate during anesthesia,although a statistically significant difference was noted among the traditional anesthesia and the STA groups even before anesthesia.During the restorative procedure,less pain was perceived by STA patients on the Wong-Baker FACES pain scale,which was statistically significant(P<0.001).Analyses of post-procedure patient responses showed that STA patients had a significantly better treatment experience and preferred to have the same method of injection in the future(P=0.04).CONCLUSION STA system can provide less painful and more comfortable restorative treatment procedures in comparison to the traditional infiltration technique.展开更多
The cast structures influencing the electrochemical corrosion behavior of Co-Cr and Ni-Cr dental alloys were studied using potentiodynamic polarization and AC impedance in 0.9% (mass fraction) NaCl solution at (37...The cast structures influencing the electrochemical corrosion behavior of Co-Cr and Ni-Cr dental alloys were studied using potentiodynamic polarization and AC impedance in 0.9% (mass fraction) NaCl solution at (37±1) ℃. The phase and microstructure of the alloys that were fabricated using two different casting methods viz. centrifugal casting and high frequency induction casting, were examined using X-ray diffraction analysis, scanning electron microscopy and energy dispersive spectroscopy. The roles of alloying elements and the passive film homogeneity on the corrosion resistance of Co-Cr-Mo and Ni-Cr-Mo dental cast alloys were reviewed. The results of electrochemical study show that the dependence of corrosion resistance on the microstructure associated with the casting methods is marginal. The Co-Cr alloy exhibits more desirable corrosion resistance properties than the Ni-Cr alloy. There is severe preferential dissolution of Ni-rich, Cr and Mo depleted zones in the Ni-Cr alloy.展开更多
Dental instrumentation has long provided insight into the mechanism of musculo-skeletal function of the gnathic system. While large population studies associate dental arch displacement(DAD), especially laterally, wit...Dental instrumentation has long provided insight into the mechanism of musculo-skeletal function of the gnathic system. While large population studies associate dental arch displacement(DAD), especially laterally, with symptoms, mandibular condyle displacement(CD) resulting from DAD has not been targeted as possibly etiologic in the production of common muscle contraction headache(CMCH) and temporo-mandibular dysfunction(TMD). The objective was to evaluate the three-dimensional nature of DAD and CD between the seated condylar position(SCP) and the intercuspal position(ICP) and to compare results derived from large deprogrammed asymptomatic and symptomatic populations. A total of 1 192 sets of dental casts collected from asymptomatic and symptomatic populations were articulated in the SCP. The initial occlusal contact, DAD, and condylar displacement were evaluated for frequency, direction, and magnitude of displacement between the SCP and ICP. The data revealed significant displacement between the SCP and ICP of the condyles(displaced most frequently inferior(down) and posterior(distal)) and substantially increased frequency and magnitude of displacement of the dental arches(with posterior premature occlusal contacts, increased overjet, decreased overbite, midline differences, and occlusal classification changes) in symptomatic subjects. These discrepancies were statistically significant and clinically significant. The data support the concept of increased DAD and CD with dysfunction. Transverse condylar displacement, commonly presenting with dental cross bite, may be associated with CMCH and TMD. Displacement of the mandibular condyle may be an etiologic factor in CMCH and dysfunction of the temporo-mandibular joint.展开更多
AIM:To design and validate broad-range 16S rRNA primers for use in high throughput sequencing to classify bacteria isolated from the human foregut microbiome.METHODS:A foregut microbiome dataset was constructed using ...AIM:To design and validate broad-range 16S rRNA primers for use in high throughput sequencing to classify bacteria isolated from the human foregut microbiome.METHODS:A foregut microbiome dataset was constructed using 16S rRNA gene sequences obtained from oral,esophageal,and gastric microbiomes produced by Sanger sequencing in previous studies represented by 219 bacterial species.Candidate primers evaluated were from the European rRNA database.To assess the effect of sequence length on accuracy of classification,16S rRNA genes of various lengths were created by trimming the full length sequences.Sequences spanning various hypervariable regions were selected to simulate the amplicons that would be obtained using possible primer pairs.The sequences were compared with full length 16S rRNA genes for accuracy in taxonomic classification using online software at the Ribosomal Database Project (RDP).The universality of the primer set was evaluated using the RDP 16S rRNA database which is comprised of 433 306 16S rRNA genes,represented by 36 phyla.RESULTS:Truncation to 100 nucleotides(nt)downstream from the position corresponding to base 28 in the Escherichia coli 16S rRNA gene caused misclassification of 87(39.7%)of the 219 sequences,compared with misclassification of only 29(13.2%)sequences with truncation to 350 nt.Among 350-nt sequence reads within various regions of the 16S rRNA gene,the reverse read of an amplicon generated using the 343F/798R primers had the least(8.2%)effect on classification.In comparison,truncation to 900 nt mimicking single pass Sanger reads misclassified 5.0%of the 219 sequences.The 343F/798R amplicon accurately assigned 91.8%of the 219 sequences at the species level.Weighted by abundance of the species in the esophageal dataset,the 343F/798R amplicon yielded similar classification accuracy without a significant loss in species coverage(92%).Modification of the 343F/798R primers to 347F/803R increased their universality among foregut species.Assuming that a typicalpolymerase chain reaction can tolerate 2 mismatches between a primer and a template,the modified 347F and 803R primers should be able to anneal 98%and 99.6%of all 16S rRNA genes in the RDP database.CONCLUSION:347F/803R is the most suitable pair of primers for classification of foregut 16S rRNA genes but also possess universality suitable for analyses of other complex microbiomes.展开更多
文摘Background: Electronic cigarette (e-cigs) smoking is substitutional to traditional cigarette smoking to reduce the dangerous combustion of products. Moreover, passive smoking is involuntarily tobacco smoking due to the exposure to cigarette or tobacco smoke among non-smokers and due to there being little knowledge about the impact of passive e-cigs smoking on periodontal status and salivary pH. Therefore, the present study aimed to evaluate the effect of e-cigs smoking habit on periodontal tissue and salivary pH among some passive e-cigs smokers referred to the college of dentistry clinics, King Khalid University. Material and Methods: Ninety male participants who were referred to the college of dentistry clinics at King Khalid University were included in the study. Age, gender, e-cigs smoking, and general health were recorded. The participants were divided into three equal groups (n = 30) as follows: Group I (Non-passive e-cigs smokers and non-smokers) as the control group, Group II (e-cigs users), and Group III (Passive e-cigs smokers). Salivary pH, plaque control record (PCR), gingival bleeding index (GBI), clinical attachment loss (CAL), percentage of radiographic bone loss (% RBL), periodontal pocket depth (PPD), more than 5 missing teeth due to periodontal diseases (>5 MTDP), tooth mobility (TM), furcation involvement (FI), Bite collapse (BC), and less than 20 remaining teeth (10 Opposing pairs) (L20RT) as well as HbA1c were recorded. ANOVA test was used to the comparison between Groups I, II, and III in the participants’ ages and periodontitis staging clinical findings. The mean of participants’ age groups, the mean of salivary pH values of study groups, and the periodontitis staging complexity and HbA1c were compared between groups with the ANOVA test, Tukey’s test, and the chi-square test. P-value was recorded, and less than 0.5 was considered a statistically significant difference (p Results: The e-cigs users group revealed higher means of PCR, GBI %RBL values, and the participants percentages of >5 MTDP, TM, FI, L20RT, and diabetes mellitus (DM) among participants compared to the passive e-cigs smokers group and control group except for the participants percentage of BC among the participants, which was higher among the control group participants. The differences were not significant in PCR, GBI, %RBL and DM (p > 0.5) and significant in >5 MTDP, TM, FI, L20RT and smoking (p 7% values compared to the e-cigs users group and control group participants. The differences were not significant in CAL and PPD (p > 0.5) and significant in the participants percentages of salivary pH values (p Conclusion: The e-cigs smoking habit was the cause of an increase in periodontal disease severity among the electronic smokers rather than passive e-cigs smokers, although the salivary pH was higher in the latter.
文摘The aim of the present study was to assess the dietary habits and oral hygiene practice of dental students in a new dental school. A self-administered structured closed-ended questionnaire on demographic characteristics, medical history, oral hygiene and dietary habits was distributed to dental students. Results showed that One third of students indicated that they don’t consume low pH beverages (soft drinks) at all, while 48.9% drink a soft drink or two a day. Students took varying amount of time to consume their drinks. The majority of participants consumed citric juices, fruits and/or pickles at least once a day. 91.3% of students use either soft (41.8%) or medium (49.5%) toothbrush. Only a fifth (16.9%) of the students brush their teeth after drinking soft drinks and 58.2% brush their teeth after vomiting. In conclusion, young adults need to be aware about their dietary habits & oral hygiene, and also a proper dental health program needs to be applied.
文摘BACKGROUND Accreditation processes are extensively employed to guarantee the quality of higher education institutions.However,this process can potentially generate a stressful atmosphere for staff,thus impacting their ability to perform optimally under pressure.AIM To examine the knowledge of the National Commission for Academic Assessment and Accreditation(NCAAA)and its effects on perceived stress among dental college staff before and after the program accreditation process.METHODS The present cross-sectional questionnaire-based study included 300 employees from three dental colleges.The same employees had to fill out the questionnaire 1 mo after the NCAAA process.RESULTS Approximately 51.33%of the included employees believed that NCAAA is essential to attract quality students to join the program before and after the program.A total of 44.67%felt that their stress was high before,and 31.33%had low stress levels before and after NCAAA.These findings were statistically significant(P≤0.05).CONCLUSION NCAAA raised the prestige of the institution and specific programmes and increased prospects to attract better students,staff,and money,according to the employees.In addition to their needed teaching,research,and other service responsibilities,this work requires a tremendous amount of faculty effort and may cause them stress.
文摘Tooth enamel is a complex mineralized tissue consisting of long and parallel apatite crystals configured into decussating enamel rods. In recent years, multiple approaches have been introduced to generate or regenerate this highly attractive biomaterial characterized by great mechanical strength paired with relative resilience and tissue compatibility. In the present review, we discuss five pathways toward enamel tissue engineering,(i) enamel synthesis using physico-chemical means,(ii) protein matrix-guided enamel crystal growth,(iii) enamel surface remineralization,(iv) cell-based enamel engineering, and(v) biological enamel regeneration based on de novo induction of tooth morphogenesis. So far, physical synthesis approaches using extreme environmental conditions such as pH, heat and pressure have resulted in the formation of enamel-like crystal assemblies.Biochemical methods relying on enamel proteins as templating matrices have aided the growth of elongated calcium phosphate crystals. To illustrate the validity of this biochemical approach we have successfully grown enamel-like apatite crystals organized into decussating enamel rods using an organic enamel protein matrix. Other studies reviewed here have employed amelogeninderived peptides or self-assembling dendrimers to re-mineralize mineral-depleted white lesions on tooth surfaces. So far, cell-based enamel tissue engineering has been hampered by the limitations of presently existing ameloblast cell lines. Going forward, these limitations may be overcome by new cell culture technologies. Finally, whole-tooth regeneration through reactivation of the signaling pathways triggered during natural enamel development represents a biological avenue toward faithful enamel regeneration. In the present review we have summarized the state of the art in enamel tissue engineering and provided novel insights into future opportunities to regenerate this arguably most fascinating of all dental tissues.
文摘The aim of this article was to analyze the theories underpinning dental fear, anxiety and phobias. To be included, articles must have been published between the years of 1949 and 2013 concerning fears and phobias within dentistry and/or psychiatry. Of 200 articles originally under review, 140 were included and reviewed by the authors.Five specific pathways relating to dental fear and anxiety were identified; Cognitive Conditioning, Informative, Visual Vicarious, Verbal Threat, and Parental. Eight currently accepted management techniques across all dental disciplines for dental fear and anxiety were identified. Further research is required to identify clinical diagnosis and treatment for fears originating from different pathways.
文摘BACKGROUND Basal cell carcinoma(BCC)is a slow-growing malignant tumor characterized by local invasiveness but an exceptionally rare metastatic potential.It ideally affects sun-exposed skin of older patients with more propensity for the facial region.AIM To evaluate the different clinicopathological characteristics of the facial BCC and the efficacy and safety of diode laser for the treatment of these lesions.METHODS We retrospectively reviewed facial BCC lesions of<1.5 cm in diameter and subjected them to diode laser ablation during the period from September 2016 to August 2021 at Al-Ramadi Teaching Hospital,Ramadi City,Iraq.Data matching the age,gender,duration,site,and clinical and histological types were registered for every subject.The functional and aesthetic outcomes and complications following diode laser ablation for each patient were also recorded.RESULTS Of 67 patients with facial BCC,there was 65.67%from the age group≥60 years and 58.21%males.The mean duration of the lesions was 5.15±1.836 mo.The most involved location was the nose(29.85%).About half of the cases belong to the noduloulcerative type.Solid histological type comprises 40.3%of the cases,while the least was keratotic(13.4%).Moreover,65.2%of the solid cases were from the age group≤60 years and 38.6%of the adenoid type from the age group>60 years(P value=0.007).Excellent aesthetic and functional outcomes were reported in all cases after 6 mo of follow-up.Few complications were reported after diode laser ablation.CONCLUSION Facial BCC was mostly seen in the elderly and men.The mean duration was 5.15 mo.The nose was the commonest involved site.Noduloulcerative lesions were seen in approximately half of the lesions.The age of the patients determined the histological type of the lesion(solid type was mostly seen in the age group≤60 years,while,adenoid in the age group>60 years).Diode laser ablation showed excellent functional and aesthetic outcomes following a 6-mo follow-up.
基金Supported by the Princess Nourah Bint Abdulrahman University Researchers Supporting Project,No.PNURSP2023R363.
文摘BACKGROUND The use of advanced platelet-rich fibrin(A-PRF)membranes for guided bone and tissue regeneration in through-and-through defects after endodontic surgery was explored in three cases.CASE SUMMARY Herein,three patients presented to the endodontic clinic suffering from apical periodontitis,associated with large bone resorption and related to previously endodontically treated teeth.Periapical surgery was indicated in these cases and the osteotomy site was covered by A-PRF membrane.Cone-beam computed tomography(CBCT)was used to assess the cases before and after the surgery.CONCLUSION Four months post-surgery,the recall CBCT scan showed complete obliteration of the osteotomy with newly formed bone.A-PRF membrane showed promising results and was an advantageous addition to surgical endodontic treatment.
文摘Cancer is a disease that is rapidly expanding in prevalence all over the world.Cancer cells canmetastasize,or spread,across the body and impact several different cell types.Additionally,the incidence rates of several subtypes of cancer have been on the rise in India.The countermeasures for the cancer disease can be taken by determining the specific expansion rate of each type.To rank the various forms of cancer’s rate of progression,we used some of the available data.Numerous studies are available in the literature which show the growth rate of cancer by different techniques.The accuracy of the scheme in determining the highest growth rate may vary due to the variation in the dependent factors.Within the context of this research,the Fuzzy triangular technique for order preference by similarity to ideal solution(TOPSIS),is utilized to rank the various categorizations of cancer with the help of four groups of medical professionals acting in the capacity of decision-makers.The number of decision-makers may variate according to the required accuracy of results.The findings of the three-dimensional Fuzzy TOPSIS analysis categorize each variety of cancer according to the rate at which it spreads over time.Numerical results along with visual representation are presented to examine the efficiency of our proposed work.
文摘Indian medicinal plants are referred to as the“nectar of life”owing to their phytochemicals and bioactive complexes that are beneficial in treating diseases.Coronavirus disease 2019(COVID-19)is a global health issue without any proper medication.The indigenous plants of India can be exploited to control the precise signs of SARS-CoV-2.The Ministry of AYUSH(Ayurveda,Yoga and Naturopathy,Unani,Siddha,and Homeopathy)has advised routine usage of medicinal plants for COVID-19.Medicinal plants like Zingiber officinalis,Azadirachta indica,Ocimum sanctum,Nigella sativa,Withania somnifera,Curcuma longa,Piper nigrum,Allium sativum,Tinospora cordifolia,etc.have immunity-boosting,antiviral,antibacterial,antioxidant and anti-inflammatory actions that can suppress and treat symptoms of COVID-19.In vitro,in vivo as well as in silico validation,these phytochemicals can help us to manage and treat COVID-19 disease.This integration of traditional knowledge in the prophylaxis of corona infection and current skills validating it for the development of precise and powerful therapeutic approaches will more efficiently resolve different clinical aspects of COVID-19.The review focuses on both traditional and emergent methods to prevent and treat COVID-19 with various Indian medicinal plants along with their phytochemicals.
文摘Objective: To assess the actual practical attitude and knowledge of dental implants among senior dental students and general dentists graduated from some Saudi and Non-Saudi dental schools. Methods: A total of 300 senior dental students and general dentists participated in the study. Hard copies of the self-designed, multiple-choice questionnaires were distributed to all participants. The questionnaire consisted of 31 questions in five parts. Data were collected and analyzed using Chi-square test and t-test, where p Results: There is a statistically significant relationship between the participants’ answers, and their dental schools. Participants’ general knowledge, training, and teaching of dental implants, as well as information about restorations retained for the dental implants, were higher among participants from Saudi dental schools than participants from non-Saudi dental schools, while the information about dental implants was higher among participants from non-Saudi dental schools than participants from Saudi dental schools. Conclusion: We conclude that the actual practical attitude and knowledge of dental implants among participants in the current study was insufficient. Therefore, dental implant education in the undergraduate curricula of dental schools surveyed should be updated to include teaching, laboratory training, and preclinical and clinical training.
文摘Objective: To assess daily lifestyle habits as risk factors for plaque-induced gingivitis and periodontitis severity and grading among samples of dental students at King Khalid University. Material and Methods: This study included 150 male participants. They were divided according to the levels into three equal groups: levels 5, 6, and 7 (group I), levels 8, 9, 10 (group II) and levels 11, 12, and interns (group III). This study consisted of questions related to age, gender, educational level, father’s education, mother’s education, home ownership, brushing teeth more than or twice a day, in addition to daily lifestyle habits that were daily smoking, daily use of sugary drinks, and daily use of sugary foods. Some clinical parameters of plaque-induced gingivitis and periodontitis and the percentage of radiographic bone loss were recorded. All data were collected and analyzed using Tukey’s test and Chi-square test. A P-value of less than 0.5 (p Results: One hundred fifty male dental students of different levels in the college of dentistry at King Khalid University participated in the study in three groups (I, II, and III). The mean age of group III is more than that of group II and group I, with highly statistically significant differences (p 30%) were more among the participants in group I than the participants in groups III and II. There was an increase in the percentage of affected participants with stages III and IV of clinical attachment loss (CAL), periodontal pocket depth (PPD), radiographic bone loss (%RBL), tooth mobility, as well as glycated hemoglobin (HbA1c) test values (>7%), and the number of cigarettes smoked per day (>10 cigs) in group III more than in group II and I. Conclusion: We conclude that the severity and grading of plaque-induced gingivitis were higher among the participants in group I, while the severity and grading of periodontitis were higher among the participants in group III due to the different impact of their daily lifestyle habits.
基金supported by a K08AR069099 (P.L.) from the National Institutes of Health/ National Institute of Arthritis and Musculoskeletal and Skinsupported by an R01AG056169 and a gift by the Patricia and Frank Zarb Family+5 种基金supported by an F30AG072834 from the National Institutes of Health/National Institute on Agingfunded through NIH Grant S10OD010751 and the Preclinical Imaging Laboratorypartially supported by the Laura and Isaac Perlmutter Cancer Center Support Grant NIH/NCI 5P30CA016087NIBIB Biomedical Technology Resource Center Grant NIH P41 EB017183supported in part by grant P30CA016087 from the National Institutes of Health/National Cancer Institutepartially supported by the Cancer Center Support Grant P30CA016087 at the Laura and Isaac Perlmutter Cancer Center。
文摘Skeletal stem and progenitor cells(SSPCs) perform bone maintenance and repair. With age, they produce fewer osteoblasts and more adipocytes leading to a loss of skeletal integrity. The molecular mechanisms that underlie this detrimental transformation are largely unknown. Single-cell RNA sequencing revealed that Notch signaling becomes elevated in SSPCs during aging. To examine the role of increased Notch activity, we deleted Nicastrin, an essential Notch pathway component, in SSPCs in vivo. Middle-aged conditional knockout mice displayed elevated SSPC osteo-lineage gene expression, increased trabecular bone mass, reduced bone marrow adiposity, and enhanced bone repair. Thus, Notch regulates SSPC cell fate decisions, and moderating Notch signaling ameliorates the skeletal aging phenotype, increasing bone mass even beyond that of young mice. Finally, we identified the transcription factor Ebf3 as a downstream mediator of Notch signaling in SSPCs that is dysregulated with aging, highlighting it as a promising therapeutic target to rejuvenate the aged skeleton.
基金supported by National Institute of Health/National Institute of Dental and Craniofacial Research training grant T32DE007200
文摘Periodontal disease has been recently linked to a variety of systemic conditions such as diabetes, cardio-vascular disease, preterm delivery, and oral cancer. The most common bacteria associated with periodontal disease, Porphyromonas gingivalis (P. gingivalis) has not yet been studied in the malignant gingival tissues. The objective of this study was to investigate the presence of P. gingivalis in specimens from squamous cell carcinoma patients. We have performed immunohistochemical staining to investigate the presence of P. gingivalis and Streptococcus gordonii (S. gordonii), a non invasive oral bacteria, in paraffin embedded samples of gingival squamous cell carcinoma (n=10) and normal gingiva (n=5). Staining for P. gingivalis revealed the presence of the bacteria in normal gingival tissues and gingival carcinoma, with higher levels (more than 33%, P<0.05) detected in the carcinoma samples. The staining intensity was also significantly enhanced in the malignant tissue by 2 folds (P<0.023) compared to specimens stained for the non-invasive S. gordonii. P. gingivalis is abundantly present in malignant oral epithelium suggesting a potential association of the bacteria with gingival squamous cell carcinoma.
基金partly supported by research grant funding:NIH-NIAMS R01- AR054616 (SEH), NIH-NIDCR T32-DE14318 (Rakian) and F32-DE018865 (Yang)supported by UTHSCSA, NIH-NCI P30-CA54174 (CTRC at UTHSCSA) and NIH-NIA P01-AG19316supported by Open Fund of State Key Laboratory of Oral Diseases, Sichuan University
文摘Formation of the periodontium begins following onset of tooth-root formation in a coordinated manner after birth. Dental follicle progenitor cells are thought to form the cementum, alveolar bone and Sharpey's fibers of the periodontal ligament (PDL). However, little is known about the regulatory morphogens that control differentiation and function of these progenitor cells, as well as the progenitor cells involved in crown and root formation. We investigated the role of bone morphogenetic protein-2 (Bmp2) in these processes by the conditional removal of the Bmp2 gene using the Sp7-Cre-EGFP mouse model. Sp7-Cre-EGFP first becomes active at E18 in the first molar, with robust Cre activity at postnatal day 0 (P0), followed by Cre activity in the second molar, which occurs after P0. There is robust Cre activity in the periodontium and third molars by 2 weeks of age. When the Bmp2 gene is removed from Sp7+ (Osterix+) cells, major defects are noted in root, cellular cementum and periodontium formation. First, there are major cell autonomous defects in root-odontoblast terminal differentiation. Second, there are major alterations in formation of the PDLs and cellular cementum, correlated with decreased nuclear factor IC (Nfic), periostin and α-SMA+ cells. Third, there is a failure to produce vascular endothelial growth factor A (VEGF-A) in the periodontium and the pulp leading to decreased formation of the microvascular and associated candidate stem cells in the Bmp2-cKOSp7-Cre-EGFP . Fourth, ameloblast function and enamel formation are indirectly altered in the Bmp2-cKOSp7-Cre-EGFP . These data demonstrate that the Bmp2 gene has complex roles in postnatal tooth development and periodontium formation.
基金supported by the National Natural Science Foundation of China (No. 81500814) (SXL)the National Natural Science Foundation of China (No. 81430012 and No. 81170939) (XJ)+2 种基金the National Basic Research Program of China (973 Program, 2012CB933604)the National Science Fund for Distinguished Young Scholars of China (No. 81225006)the National Institutes of Health Grants DE025014 and R56DE022789 (JQF)
文摘Bone morphogenetic proteins(BMPs) have multiple roles in skeletal development, homeostasis and regeneration. BMPs signal via type I and type II serine/threonine kinase receptors(BMPRI and BMPRII). In recent decades, genetic studies in humans and mice have demonstrated that perturbations in BMP signaling via BMPRI resulted in various diseases in bone, cartilage, and muscles. In this review, we focus on all three types of BMPRI, which consist of activin-like kinase 2(ALK2, also called type IA activin receptor), activinlike kinase 3(ALK3, also called BMPRIA), and activin-like kinase 6(ALK6, also called BMPRIB). The research areas covered include the current progress regarding the roles of these receptors during myogenesis,chondrogenesis, and osteogenesis. Understanding the physiological and pathological functions of these receptors at the cellular and molecular levels will advance drug development and tissue regeneration for treating musculoskeletal diseases and bone defects in the future.
文摘Helicobacter pylori(H.pylori)infection is one of the most common bacterial infections in humans.Although H.pylori may be detected in the stomach of approximately half of the world’s population,the mechanisms of transmission of the microorganism from individual to individual are not yet clear.Transmission of H.pylori could occur through iatrogenic,fecal-oral,and oral-oral routes,and through food and water.The microorganism may be transmitted orally and has been detected in dental plaque and saliva.However,the role of the oral cavity in the transmission and recurrence of H.pylori infection has been the subject of debate.A large number of studies investigating the role of oral hygiene and periodontal disease in H.pylori infection have varied significantly in terms of their methodology and sample population,resulting in a wide variation in the reported results.Nevertheless,recent studies have not only shown that the microorganism can be detected fairly consistently from the oral cavity but also demonstrated that the chances of recurrence of H.pylori infection is more likely among patients who harbor the organism in the oral cavity.Furthermore,initial results from clinical trials have shown that H.pylori-positive dyspeptic patients may benefit from periodontal therapy.This paper attempts to review the current body of evidence regarding the role of dental plaque,saliva,and periodontal disease in H.pylori infection.
文摘BACKGROUND Contemporary innovations in the area of local anesthesia have attempted to provide an absolutely pain free experience for patients.Since the introduction of Computer-Controlled Local Anesthetic Delivery Systems to dentistry,many studies have compared its efficacy and safety to conventional anesthesia.However,very few studies have compared single tooth anesthesia(STA)and traditional local anesthesia.AIM To compare pain rating,changes in blood pressure,and heart rate during the local anesthetic injection.The secondary objectives were to measure the patients’level of satisfaction and the differences in anesthetic efficiency between the STA system and traditional local infiltration.METHODS A randomized controlled trial was conducted and a total of 80 patients with dental restorative needs were enrolled for the study.The patients were evaluated for their general physical status and oral clinical findings before enrollment.Information regarding perceived pain,changes in heart rate and blood pressure,and patients’satisfaction was collected using an electronic data form and was analyzed using paired and unpaired t-tests.RESULTS No significant difference was noted in perceived pain(P=0.59)and systolic blood pressure(P=0.09)during anesthetic injection using both traditional and STA techniques.STA patients had a significantly higher heart rate during anesthesia,although a statistically significant difference was noted among the traditional anesthesia and the STA groups even before anesthesia.During the restorative procedure,less pain was perceived by STA patients on the Wong-Baker FACES pain scale,which was statistically significant(P<0.001).Analyses of post-procedure patient responses showed that STA patients had a significantly better treatment experience and preferred to have the same method of injection in the future(P=0.04).CONCLUSION STA system can provide less painful and more comfortable restorative treatment procedures in comparison to the traditional infiltration technique.
文摘The cast structures influencing the electrochemical corrosion behavior of Co-Cr and Ni-Cr dental alloys were studied using potentiodynamic polarization and AC impedance in 0.9% (mass fraction) NaCl solution at (37±1) ℃. The phase and microstructure of the alloys that were fabricated using two different casting methods viz. centrifugal casting and high frequency induction casting, were examined using X-ray diffraction analysis, scanning electron microscopy and energy dispersive spectroscopy. The roles of alloying elements and the passive film homogeneity on the corrosion resistance of Co-Cr-Mo and Ni-Cr-Mo dental cast alloys were reviewed. The results of electrochemical study show that the dependence of corrosion resistance on the microstructure associated with the casting methods is marginal. The Co-Cr alloy exhibits more desirable corrosion resistance properties than the Ni-Cr alloy. There is severe preferential dissolution of Ni-rich, Cr and Mo depleted zones in the Ni-Cr alloy.
文摘Dental instrumentation has long provided insight into the mechanism of musculo-skeletal function of the gnathic system. While large population studies associate dental arch displacement(DAD), especially laterally, with symptoms, mandibular condyle displacement(CD) resulting from DAD has not been targeted as possibly etiologic in the production of common muscle contraction headache(CMCH) and temporo-mandibular dysfunction(TMD). The objective was to evaluate the three-dimensional nature of DAD and CD between the seated condylar position(SCP) and the intercuspal position(ICP) and to compare results derived from large deprogrammed asymptomatic and symptomatic populations. A total of 1 192 sets of dental casts collected from asymptomatic and symptomatic populations were articulated in the SCP. The initial occlusal contact, DAD, and condylar displacement were evaluated for frequency, direction, and magnitude of displacement between the SCP and ICP. The data revealed significant displacement between the SCP and ICP of the condyles(displaced most frequently inferior(down) and posterior(distal)) and substantially increased frequency and magnitude of displacement of the dental arches(with posterior premature occlusal contacts, increased overjet, decreased overbite, midline differences, and occlusal classification changes) in symptomatic subjects. These discrepancies were statistically significant and clinically significant. The data support the concept of increased DAD and CD with dysfunction. Transverse condylar displacement, commonly presenting with dental cross bite, may be associated with CMCH and TMD. Displacement of the mandibular condyle may be an etiologic factor in CMCH and dysfunction of the temporo-mandibular joint.
基金Supported by(in part)Grants UH2CA140233 from the Human Microbiome Project of the NIH Roadmap Initiative and National Cancer InstituteR01AI063477 from the National Institute of Allergy and Infectious Diseases+1 种基金DE-11443 from the National Institute of Dental and Craniofacial ResearchU19DE018385 from the National Institute of Dental & Craniofacial Research
文摘AIM:To design and validate broad-range 16S rRNA primers for use in high throughput sequencing to classify bacteria isolated from the human foregut microbiome.METHODS:A foregut microbiome dataset was constructed using 16S rRNA gene sequences obtained from oral,esophageal,and gastric microbiomes produced by Sanger sequencing in previous studies represented by 219 bacterial species.Candidate primers evaluated were from the European rRNA database.To assess the effect of sequence length on accuracy of classification,16S rRNA genes of various lengths were created by trimming the full length sequences.Sequences spanning various hypervariable regions were selected to simulate the amplicons that would be obtained using possible primer pairs.The sequences were compared with full length 16S rRNA genes for accuracy in taxonomic classification using online software at the Ribosomal Database Project (RDP).The universality of the primer set was evaluated using the RDP 16S rRNA database which is comprised of 433 306 16S rRNA genes,represented by 36 phyla.RESULTS:Truncation to 100 nucleotides(nt)downstream from the position corresponding to base 28 in the Escherichia coli 16S rRNA gene caused misclassification of 87(39.7%)of the 219 sequences,compared with misclassification of only 29(13.2%)sequences with truncation to 350 nt.Among 350-nt sequence reads within various regions of the 16S rRNA gene,the reverse read of an amplicon generated using the 343F/798R primers had the least(8.2%)effect on classification.In comparison,truncation to 900 nt mimicking single pass Sanger reads misclassified 5.0%of the 219 sequences.The 343F/798R amplicon accurately assigned 91.8%of the 219 sequences at the species level.Weighted by abundance of the species in the esophageal dataset,the 343F/798R amplicon yielded similar classification accuracy without a significant loss in species coverage(92%).Modification of the 343F/798R primers to 347F/803R increased their universality among foregut species.Assuming that a typicalpolymerase chain reaction can tolerate 2 mismatches between a primer and a template,the modified 347F and 803R primers should be able to anneal 98%and 99.6%of all 16S rRNA genes in the RDP database.CONCLUSION:347F/803R is the most suitable pair of primers for classification of foregut 16S rRNA genes but also possess universality suitable for analyses of other complex microbiomes.
