From an assessment of multiple chelators, clodronate has potential for use in continuous chelation.

AIM: To identify chelators which when mixed with sodium hypochlorite (NaOCl) are stable, exhibiting minimal loss of free available chlorine (FAC) over 80 min and to further investigate potential mixtures by assessing FAC over 18 h and the capacity to remove smear layer. METHODOLOGY: 0.25 mol L-1 EDTA (10%), 0.25 mol L-1 EGTA (egtazic acid), 0.25 mol L-1 CDTA (cyclohexanediaminetetraacetic acid), 0.25 mol L-1 DTPA (pentetic acid), 0.5 mol L-1 ATMP (aminotri(methylene phosphonic acid)) and 1 mol L-1 HPAA, (hydroxyphosphonoacetic acid), all at alkaline pH, were mixed equally with 5% NaOCl. 0.5 mol L-1 alkaline clodronate and 0.5 mol L-1 Na4 etidronate (15%) were mixed equally with 10% NaOCl. For all mixtures, the pH and temperature were measured over 80 min and additionally for the clodronate mixture over 18 h. Iodometric titration was used to measure the FAC of all mixtures except for HPAA. The following were compared with respect to their ability to remove smear layer: 1 mol L-1 clodronate + 10% NaOCl, 0.5 mol L-1 clodronate + 10% NaOCl, 1 mol L-1 etidronate + 10% NaOCl, 0.5 mol L-1 clodronate + 10% NaOCl and the sequences 5% NaOCl/17% EDTA/5% NaOCl and 5% NaOCl/17% EDTA. The area fraction occupied by open dentinal tubules as a percentage of the total area (% AF) from scanning electron microscopy micrographs was calculated using Image J. The results were statistically analysed with alpha set at 0.05. RESULTS: Compared to its control, the mixture 0.5 mol L-1 clodronate + 10% NaOCl lost no FAC over 18 h (P > 0.05). The FAC of 0.25 mol L-1 CDTA mixed with 5% NaOCl fell to 96%, 92%, 75% and 4.9% at 20, 40, 60 and 80 min, respectively. Temperature rises were observed in all cases except in the etidronate and clodronate mixtures. Only in the clodronate mixture did the pH remain above pH 12 for the whole experiment. Although smear layer was removed, the % AF in 1 mol L-1 clodronate + 10% NaOCl, 0.5 mol L-1 clodronate + 10% NaOCl, 1 mol L-1 etidronate + 10% NaOCl was less than for 0.5 mol L-1 etidronate + 10% NaOCl and 5% NaOCl/17% EDTA/5% NaOCl and 5% NaOCl/17% EDTA. CONCLUSION: Alkaline 0.5 mol L-1 clodronate mixed equally with 10% NaOCl has potential for use in continuous chelation, based on this assessment of stability and smear layer removal. Further research is needed to establish its efficacy and safety.

Factors affecting the rate of oxidation and resultant discolouration of tetracyclines contained in endodontic medicaments and irrigants.

AIM: To determine the effect of pH, oxygen levels and ions on tetracycline oxidation and resultant discolouration. METHODOLOGY: Solutions of demeclocycline hydrochloride or doxycycline hyclate were prepared and exposed to different pH conditions, pure oxygen or carbon dioxide, ascorbic acid or various ions (from calcium chloride, calcium nitrate, strontium chloride, magnesium chloride, zinc chloride, and bismuth nitrate). Subsequently, they were exposed to intense visible blue light (470 ± 15 nm) for 24 h. Colour change was monitored using standardized digital photography. Parametric statistical analysis employing the Wilcoxon matched-pairs signed-rank test was performed to compare the mean change in different colour channels, assessing the discolouration effect of the modified conditions. RESULTS: An acidic pH reduced discolouration, whilst alkaline pH increased it. A higher oxygen tension resulted in more discolouration, as did the presence of calcium, strontium, and bismuth ions, all of which bind to tetracyclines. Conversely, zinc and magnesium ions had a mild photoprotective effect. Ascorbic acid, an anti-oxidant, reduced the level of discolouration. CONCLUSIONS: The tendency of these tetracyclines to undergo photo-oxidation is increased by common variables present in the clinical environment. There are potential benefits from using photoprotectors and anti-oxidants in these materials, to reduce the possibility of discolouration.

qPCR assay optimisation for a clinical study comparing oral health risk in Rett syndrome.

PURPOSE: This study aimed to validate qPCR assays for specific microbiota, for use on dental plaque samples stored on Whatman FTA cards to compare relative oral health risk in Rett syndrome. METHODS: Supragingival dental plaque samples were collected, using a sterile swab, (COPAN FLOQswab™) swabbed onto Whatman FTA™ cards. DNA extraction was performed using a modified Powersoil™ protocol. Where published assays were unsuitable, species-specific qPCR assays for caries-associated, gingivitis-associated and oral-health-associated bacteria were designed using multiple sequence alignment, Primer3Plus and PrimerQuest. Assays were run using absolute quantification. Limit of detection (LOD) and limit of quantification (LOQ) were calculated, and PCR products verified by Sanger sequencing. RESULTS: Most assays allowed detection using real-time qPCR with high specificity on samples collected on FTA cards. Several assays showed low or even single gene copy numbers on the test samples. CONCLUSION: Assays were optimised for detection and evaluation of oral health risk in dental plaque samples stored on FTA cards when cold storage is not feasible, except for F. nucleatum. Several assays showed gene copy numbers less than the LOQ or outside the range of the standard curve, so there is merit in optimising these assays using digital droplet PCR.

Tooth Discoloration from 2 Silver Fluorides Used in Adults with Special Needs: A Randomized Trial.

BACKGROUND: Discoloration of carious lesions after application of silver diamine fluoride lowers patient acceptance and limits its wider use for caries arrest. OBJECTIVE: To assess lesion and tooth color changes from 2 novel silver fluoride (AgF) products and its relationship to caries activity (clinical visuo-tactile scores) and bacterial load (using laser fluorescence with the DIAGNOdent). METHODS: A split-mouth design was followed, with matched smooth surface carious lesions in the same arch in adults with special needs randomized for 1-min treatments with AgF/potassium iodide (KI) (Riva Star Aqua, SDI) and AgF/stannous fluoride (SnF2) (Caries Status Disclosing Solution; Whiteley). Standardized images taken at baseline, immediately postoperatively, and at 3-mo review were subjected to digital image analysis to calculate delta-E and to track changes in luminosity of carious lesions. RESULTS: Twelve participants were recruited in the study. A total of 56 teeth (28 pairs) were included. Significantly greater changes were seen in treated lesions than in the adjacent noncarious natural tooth structure, both immediately after treatment and at the 3-mo review (P < 0.0001). Color change and caries activity were not affected by tooth type, tooth location, plaque status, salivary status, or special needs condition. AgF/SnF2 caused transitory darkening immediately on application, while AgF/KI caused the immediate formation of yellow deposits (silver iodide). Both products caused significant darkening of treated lesions at 3 mo (P = 0.0009; P = 0.0361), with no differences between them (P = 0.506). Responding lesions showed larger and more perceptible color changes immediately after either AgF application (P = 0.002; P = 0.024). CONCLUSIONS: Both AgF products were highly effective for caries arrest in this patient population. Despite minor differences in the appearance of treated lesions at the time of application, both products lead to similar darkening of treated sites at 3 mo. KNOWLEDGE TRANSFER STATEMENT: This study shows the usefulness of silver fluoride used in conjunction with potassium iodide or stannous fluoride for achieving caries arrest in smooth surface lesions in adults with special needs. Patients need to be informed that long-term staining of the lesion occurs with both, similar to silver diamine fluoride.

A longitudinal case-control study of caries development from birth to 36 months.

BACKGROUND/AIMS: The aim of this longitudinal case-control study was to investigate variables associated with caries development from birth to 36 months. METHODS: Children (n = 1,017) who were followed up every 6 months from birth to 36 months were grouped into those that developed caries by age 30 and 36 months, respectively, and compared with children without caries. RESULTS: By 30 months (n = 608) there were 24 children (4%) who had caries and an additional 23 developed first caries at 36 months (n = 552), giving a total prevalence of 47 children with caries (9%) at 36 months. Children who showed caries by 30 months were more likely to be mutans streptococci (MS) colonised by 18 months (p = 0.001) compared to those who developed caries at 36 months, and showed the following variables: MS counts of >10(5) CFU/ml at 12 months (p = 0.005), missing enamel (p = 0.001), sugar in pacifier at 18 months (p = 0.02), child sleeping next to mother at 6, 18 and 24 months (p = 0.001 to p = 0.02), and exposure to household cigarette smoke at 24 months (p = 0.02). Caries at 36 months was associated with pregnancy problems (p = 0.024), mother having dental cavitations (p = 0.001) and MS presence at 36 months (adjusted odds ratio, AOR = 0.1, p = 0.01 for counts <10(5) CFU/ml). Caries at both 30 and 36 months was associated with MS presence at 18 months (AOR = 6.3, p = 0.005 and AOR = 4.9, p = 0.01). CONCLUSIONS: Children who developed caries by 30 months are colonised by MS at younger ages and with higher MS counts compared with children who develop caries at 36 months.

Oral complications associated with metal ion release from oral piercings: a systematic review.

PURPOSE: This systematic review explored dental complications associated with metal ion release from oral piercings using the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. METHODS: Item retrieval from October 2022 to December 2022 from databases, such as Cochrane Central Register of Controlled Trials, Medline, PubMed, Embase, Scopus and Web of Science, using predefined search terms was undertaken by two independent reviewers. Data were extracted and risk of bias was assessed using the Joanna Briggs Institute (JBI) critical appraisal checklist. From 1509 identified studies, 25 were included for analysis. RESULTS: Of the 25 studies, 20 included both clinical examination and questionnaire-based data. The remaining five studies were deemed low quality based on the Joanna Briggs Institute criteria. The average time piercings were worn ranged between 5 and 48 months. Most studies did not investigate complications from metal ion release. Only two studies examined the direct effects of metal ion release and showed that metal ions may cause hypersensitivity reactions and mucosal changes. Other soft tissue complications were reported, with gingival recession noted in 16 out of 25 studies, especially due to lip piercings. Studies reporting other complications were as follows: swelling (9), pain (8), infection (6), bleeding (6), inflammation (5), alterations to speech, eating and/or swallowing (5), changes to taste or metallic taste (5), and mucosal changes (4). Ten studies reported tooth chipping from tongue piercings. CONCLUSION: Oral piercings leach metal ions into surrounding tissues which may cause local mucosal changes. Furthermore, oral piercings cause damage to both soft and hard oral tissues, particularly gingival recession for lip piercings and tooth chipping for tongue piercings. Thus, to prevent such adverse injuries, dental professionals should discourage patients against oral piercings.

Ion release from oral piercings from in vitro acidic challenges.

OBJECTIVES: This laboratory-based study measured ion release from metallic piercings when exposed to organic acids (lactic, citric) and inorganic acids (phosphoric, hydrochloric) that could be encountered in the oral cavity. METHODS: Barbell and ring oral piercings composed of stainless steel, titanium or gold-plated titanium were submerged in 2 mL volumes of 0.1% lactic acid, 10% citric acid, 0.2% phosphoric acid, and 0.1% hydrochloric acid for 7 and 34 days. Ion release into the liquid was measured using inductively coupled plasma optical emission spectroscopy (ICPOES) and expressed in relationship to surface area. Surface changes from baseline were assessed using light and backscatter scanning electron microscopy (SEM). RESULTS: ICPOES results showed that hydrochloric and phosphoric acid caused the greatest release of material per surface area. Released elements included (ranked highest to lowest): Fe, P, Ti, Na, Cr, S, Ni, Ca, Mg, K, Si, Al, V, Mn, Ba, and Co. SEM imaging identified qualitative surface changes consistent with corrosion, for most piercing types examined. CONCLUSIONS: Under the exposure conditions used, inorganic acids cause greater metal dissolution than organic acids. Inorganic acids could therefore pose a risk of corrosion and leaching of ions from metallic oral piercings.

Positive impacts of oral health services provision by a student-led primary care clinic to an Australian rural indigenous community.

BACKGROUND: This study aimed to determine whether oral health services provision by a dental student clinical outplacement embedded within a Community Controlled Health Service positively impacted a rural Indigenous community and to explore the nature of these benefits. METHODS: Aggregated and de-identified 2017, 2018 and 2019 student-led clinic services provision data were retrospectively analysed. The change in services mix over time was measured. Rural outplacement clinic operational costs to the university were estimated. Government-funded local public dental clinic waiting list and services provision data were used to identify any student clinic establishment effect. RESULTS: The student-led clinic services mix shifted over time from mainly acute care for toothache towards prevention of disease and tooth restoration, indicating an improvement in patient oral health and correspondingly reduced system costs. Imputed value of 2017-2019 student-led clinic services provision totalled almost AUD$1 million. Government public clinic waiting list times decreased after full establishment of the student-led clinic, indicating decreased pressure on the public system. CONCLUSION: The Community Controlled Health Service and university partnership improved community oral health care access, its timely delivery and simultaneously provided valuable human capital development from the student training experience. The student-led clinic's targeted Indigenous community showed oral health improvement over time. © 2023 Australian Dental Association.

Mutans streptococci and lactobacilli colonization in predentate children from the neonatal period to seven months of age.

BACKGROUND/AIMS: The aim of this study was to investigate the colonization of mutans streptococci (MS) and lactobacilli (LB) in predentate children from the neonatal period to 7 months. METHODS: A total of 957 mother-and-child pairs were recruited from birth and followed up at 7 months. The 283 children who did not have erupted teeth at the second visit were included in the study. Oral mucosal swabs were taken, and the presence of MS and LB was determined using a commercial microbiological culture kit. RESULTS: At mean ages of 34 days and 7 months, 9 and 11% of the infants, respectively, showed the presence of MS. In contrast, LB presence increased from 24 to 47% (p < 0.0001). MS presence in the neonatal period was associated with maternal MS counts of >10(5) CFU/ml (p = 0.05), while LB presence was associated with natural birth (p = 0.03) and maternal LB presence (p = 0.02). At 7 months, MS presence was associated with maternal MS counts (p = 0.02) and LB counts of >10(5) CFU/ml (p = 0.007). Additional predictors of MS presence at 7 months were a child's MS counts of >10(5) CFU/ml at the neonatal visit (p = 0.019) and nighttime bottle feeding (p = 0.024). LB presence at 7 months was associated with maternal LB (p < 0.001) and MS presence (p = 0.02). CONCLUSIONS: MS and LB can be detected by culture in the oral cavity as early as 34 days after birth. Their infection rates increase to 11 and 47%, respectively, by the time the children reach the end of the predentate stage of oral development.

A longitudinal study comparing mutans streptococci and lactobacilli colonisation in dentate children aged 6 to 24 months.

This longitudinal study aimed to investigate variables associated with colonisation of mutans streptococci (MS) compared with lactobacilli (LB) colonisation in a cohort of children (n = 214) from the time of first tooth eruption at approximately 6 months until 24 months of age. Repeated plaque and salivary samples were collected from the same infants at 6, 12, 18 and 24 months and assayed for MS and LB using a microbiological culture kit. Children having both MS and LB increased from 4% at 6 months to 13% at 12 and 18 months to 20% at 24 months (p = 0.004). LB presence at 6 months was correlated with MS presence at 12, 18 and 24 months (r = 0.21 to r = 0.46, p = 0.02), while MS presence at 6 months correlated with LB presence at all other times (r = 0.19 to r = 0.31, p = 0.03). At 6 and 12 months, the key variables for MS colonisation included unrestored dental cavities in the mother (p = 0.03), mother not persisting with toothbrushing (p = 0.001) and bottle taken to bed at night (p = 0.033), while the only significant variable for LB colonisation was natural birth (p = 0.01). At 24 months, the significant variables for MS colonisation were condiments added to pacifier (p = 0.022) and child being uncooperative for toothbrushing (p = 0.025), while the significant variables for LB colonisation were pregnancy problems (p = 0.028) and child being uncooperative for toothbrushing (p = 0.013). The ages 6-12 months thus represent a time period when key variables may be controlled to reduce MS and LB colonisation.

Decontamination practices of paediatric crowns: a systematic review.

PURPOSE: A systematic review was conducted into paediatric crown decontamination practices using the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. METHOD: After database retrieval using predefined search terms, two reviewers independently applied the selection criteria, extracted the data, and assessed for risk of bias. From 92 potentially eligible studies, 10 were included for analysis. RESULTS: Steam sterilisation (autoclaving) was used as the gold standard for reducing biological contaminants on paediatric crowns across in vivo studies. However, autoclaving was associated with microstructural changes such as crazing and contour alterations. Furthermore, several tooth coloured crowns were liable to undergo colour changes from steam sterilisation. CONCLUSION: Ambiguous manufacturer guidelines on protocols for reprocessing and reuse after biological exposure raises concerns regarding cross contamination and leaves practitioners open to potential litigation. A better understanding of the compatibility of paediatric crowns and decontamination practices is needed. More research into alternative chairside technologies that use low temperature, such as hydrogen peroxide gas plasma sterilisation, is warranted.

Pulmonary arterial hypertension in hereditary hemorrhagic telangiectasia associated with ACVRL1 mutation: a case report.

INTRODUCTION: Hereditary hemorrhagic telangiectasia is an autosomal dominant condition with an estimated prevalence of 1 in 5000. It is characterized by the presence of abnormalities of vascular structures, and may affect many organ systems, including the lungs, brain, spinal cord, gastrointestinal tract, and liver. A causative mutation is identified in approximately 97% of patients with definite hereditary hemorrhagic telangiectasia in one of three genes including a mutation in endoglin, a mutation in a locus mapped to chromosome 5, and an activin receptor-like kinase-1 (ACVRL1) mutation that is associated with an increased incidence of primary pulmonary hypertension. Pulmonary arterial hypertension is a rare (15-25 cases per million people) but severe vascular disorder. Heritable pulmonary arterial hypertension is associated with several gene mutations, with 75% having a mutation in the bone morphogenetic protein receptor 2 (BMPR2). However, the remaining 25% of patients have other associated genetic mutations including ACVLR1, which is also associated with hereditary hemorrhagic telangiectasia. Pulmonary arterial hypertension is a rare complication in patients with hereditary hemorrhagic telangiectasia (< 1% of the hereditary hemorrhagic telangiectasia population). We describe a case report with this rare occurrence. CASE PRESENTATION: A 70-year-old white/caucasian Irish male presented for screening for hereditary hemorrhagic telangiectasia due to a history of recurrent epistaxis (once/week) and a family history suggestive of pulmonary hypertension. Genetic testing confirmed an ACVRL1 mutation, while an echocardiogram and right heart catheterization confirmed pulmonary arterial hypertension. On examination, he had several mucocutaneous telangiectasia across his face. He was commenced on tadalafil and macitentan. However, this led to increased iron deficiency anemia and pedal edema. Selexipag was also added to his drug regime. He continues to require intermittent admissions for diuresis and blood transfusions. CONCLUSION: The association of hereditary hemorrhagic telangiectasia and pulmonary arterial hypertension is rare (< 1%). Here we describe a case of hereditary hemorrhagic telangiectasia complicated with pulmonary arterial hypertension as a result of an ACVRL1 mutation. We also describe the clinical challenges of treating these two conditions together, as treatment options for pulmonary arterial hypertension tend to worsen hereditary hemorrhagic telangiectasia symptoms.

The Queensland Birth Cohort Study for Early Childhood Caries: Results at 7 Years.

AIMS: This study investigated caries predictors in 378 children remaining from a birth cohort of 1,052 at 7 y and compared the efficacy of home visits (HVs) and telephone contacts (TCs) for early childhood caries (ECC) prevention. METHODS: The HVs or TCs were made at ages 6, 12, 18, 30, and 42 mo with annual dental clinic examinations at ages 2 to 7 y. At every visit, the parents completed validated questionnaires regarding the children's family, medical, dental, and dietary histories. RESULTS: The caries prevalence increased from 2% and 6% at ages 2 and 3 y to 15%, 33%, 42%, and 52% at ages 4 to 7 y. The mean caries experience (decayed, missing, and teeth extracted due to caries) of the total cohort increased from 0.1 ± 0.5 at age 2 y to 0.2 ± 1.1 at 3 y, 0.5 ± 1.6 at 4 y, 1.1 ± 2.4 at 5 y, 1.6 ± 2.6 at 6 y, and 2.0 ± 2.7 at 7 y. The prevalence of mutans streptococci (MS) in the total cohort at years 2 to 7 was 22%, 36%, 42%, 42%, 39%, and 44%, respectively. MS was strongly correlated with caries prevalence for all years (all P < 0.001). Statistical modeling employing the generalized estimating equations identified caries predictors as holding a Health Care Card (low socioeconomic status) (P = 0.009; odds ratio [OR] = 2.05; confidence interval [CI]: 1.20-3.52), developmental defects of enamel (DDEs) (P < 0.001; OR = 1.09; CI: 1.05-1.14), and MS counts ≤105/mL (P = 0.001; OR = 1.63; CI: 1.24-2.14). By contrast, HVs were more protective than TCs for caries (P = 0.008; OR = 0.42; CI: 0.22-0.80). CONCLUSIONS: This study provides prospective, clinical evidence that MS, DDEs, and low socioeconomic status are strongly correlated with early childhood caries and that HVs are more efficacious than TCs in ECC prevention. KNOWLEDGE TRANSFER STATEMENT: This 7-y birth cohort study provides longitudinal clinical evidence that mutans streptococci, developmental defects of enamel, and low socioeconomic status are key risk indicators of early childhood caries.

Trends in Australian dental prescribing of antibiotics: 2005-2016.

BACKGROUND: Prescribing of antibiotics by dentists for surgical prophylaxis or as an adjunct to managing dental infections is a substantial part of the overall landscape for prescribed antibiotics in health care settings. METHODS: We explored trends in the antibiotic prescribing patterns of Australian dentists over the 12-year period, 2005-2016. We obtained data on dispensed prescriptions of antibiotics from registered dentists subsidized on the Pharmaceutical Benefits Scheme. RESULTS: Australian dentists were responsible for almost 7 million dispensed prescriptions of antibiotics over 12 years; an average of 24 prescriptions per year per dentist. The most commonly prescribed antibiotic was amoxicillin, followed by amoxicillin + clavulanic acid and metronidazole. These top three antibiotics constituted more than 80% of all antibiotics prescribed and their use increased dramatically over time. There was a large increase in the prescribing of broad-spectrum antibiotics over time, most of which occurred from 2011 to 2016. CONCLUSIONS: Excessive prescribing of broad-spectrum antibiotics runs contrary to national antimicrobial stewardship (AMS) initiatives and guidelines. Multifaceted educational strategies are essential to align prescribing with current best practice. High-level evidence to inform clear guidelines on antibiotic prescribing in dental infections, with audit and feedback, should reduce the inappropriate use of antibiotics in dentistry.

Reliability of software-based assessment of paediatric preparations for preformed metal crowns in the simulation laboratory.

PURPOSE: Using software for assessment of restorative work on typodonts in the simulation laboratory may enhance the objective evaluation of student work. The study aimed to evaluate the inter-rater and intra-rater reliability using 3-D scans from the Planmeca Emerald™ intra-oral scanner with Romexis Compare® software for assessing preparations for preformed metal crowns (PMCs). METHODS: Three operators independently recorded 3-D scans and digitally measured the features of 30 PMC preparations on typodont primary teeth (# 75). Using Romexis Compare® software, preparations were measured from mesial, distal and occlusal aspects. Measurements were repeated after 2 weeks. The intraclass correlation coefficient (ICC) was used to measure the reliability of measurements between operators and within the one operator. RESULTS: For measuring the extent of tooth reduction, there was excellent intra-rater reliability for each operator (ICC 0.96-0.99). The highest inter-rater reliability was for measurements of the occlusal surface (0.946 and 0.956), followed by the mesial surface (0.852 and 0.862) and then the distal surface (0.746 and 0.724). CONCLUSION: This method was useful and reliable for measuring features of PMC preparation, but with some limitations. Improving the software to provide specific assistance tools would empower greater uptake of this method as an adjunct to traditional visual grading tool in paediatric dentistry preclinical teaching.

Oral health students' perceptions of clinical reflective learning--relevance to their development as evolving professionals.

CONTEXT: A clinical professional should be a reflective practitioner, however reflective learning and deliberate clinical reflections have not traditionally featured in dentistry or dental hygiene programs. To the authors' knowledge, there are no studies exploring the perceptions of oral health students to reflective learning and clinical reflective practices. AIM: This study determined student perceptions of clinical reflective learning and its relevance to their clinical and professional development. METHODS: Reflective learning was embedded as a topic in the curriculum of the University of Queensland Bachelor of Oral Health program, within the discipline of dental hygiene practice. Reflective practices were integrated with clinical practice, and were linked with assessment requirements. Students' perceptions of clinical reflective learning were obtained via quantitative and qualitative analyses of sequenced questionnaires. Computer-assisted thematic analyses of the students' reflective journals, reflective essays and summary notes from in-class group discussions validated students' perceptions. RESULTS: Students (n = 17) perceived clinical reflective learning as relevant, and useful for consolidating their clinical learning and accelerating their professional development. In particular, students gained insights about their strengths and weaknesses, thought more deeply about what they were doing in the clinic, and unpacked difficult concepts. CONCLUSION: Students views of clinical reflective learning in this program were positive. They believed that the deliberate reflective process assisted their clinical learning and professional development.

Randomized Controlled Study to Evaluate Microbial Ecological Effects of CPP-ACP and Cranberry on Dental Plaque.

INTRODUCTION: Ecological approaches to dental caries prevention play a key role in attaining long-term control over the disease and maintaining a symbiotic oral microbiome. OBJECTIVES: This study aimed to investigate the microbial ecological effects of 2 interventional dentifrices: a casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) dentifrice and the same dentifrice supplemented with a polyphenol-rich cranberry extract. METHODS: The interventional toothpastes were compared with each other and with an active control fluoride dentifrice in a double-blinded randomized controlled trial. Real-time quantitative polymerase chain reaction (qPCR) analysis was used to determine changes in the bacterial loads of 14 key bacterial species (8 caries associated and 6 health associated) in the dental plaque of trial participants after they used the dentifrices for 5 to 6 wk. RESULTS: From the baseline to the recall visit, significant differences were observed between the treatment groups in the bacterial loads of 2 caries-associated bacterial species (Streptococcus mutans [P < 0.001] and Veillonella parvula [P < 0.001]) and 3 health-associated bacterial species (Corynebacterium durum [P = 0.008], Neisseria flavescens [P = 0.005], and Streptococcus sanguinis [P < 0.001]). Compared to the fluoride control dentifrice, the CPP-ACP dentifrice demonstrated significant differences for S. mutans (P = 0.032), C. durum (P = 0.007), and S. sanguinis (P < 0.001), while combination CPP-ACP-cranberry dentifrice showed significant differences for S. mutans (P < 0.001), V. parvula (P < 0.001), N. flavescens (P = 0.003), and S. sanguinis (P < 0.001). However, no significant differences were observed in the bacterial load comparisons between the CPP-ACP and combination dentifrices for any of the targeted bacterial species (P > 0.05). CONCLUSIONS: Overall, the results indicate that dentifrices containing CPP-ACP and polyphenol-rich cranberry extracts can influence a species-level shift in the ecology of the oral microbiome, resulting in a microbial community less associated with dental caries (Australian New Zealand Clinical Trial Registry ANZCTR 12618000095268). KNOWLEDGE TRANSFER STATEMENT: The results of this randomized controlled trial indicate that dentifrices containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and polyphenol-rich cranberry extracts were able to beneficially modulate the microbial ecology of dental plaque in a group of high caries-risk patients. This could contribute toward lowering the risk of developing new caries lesions, an important goal sought by patients, clinicians, and policy makers.

Identification of a novel high molecular weight protein preferentially expressed by sinusoidal endothelial cells in normal human tissues.

Mouse mAb MS-1, raised against human spleen, detects an endothelial cell antigen abundantly expressed by the sinusoidal endothelia of spleen, lymph node, liver, and adrenal cortex, but absent from nonsinusoidal continuous endothelia in these organs. Immunoelectron microscopy of splenic tissue demonstrates that the MS-1 antigen is predominantly deposited at zones of intercellular contact between adjacent sinusoidal endothelial cells. mAb MS-1 also reacts with a variable proportion of high endothelial venules in tonsil, but not in other lymphoid tissues, and with an interstitial dendritic cell population most abundant in placenta. mAb MS-1 does not react with cultured resting or mediator- activated human umbilical vein endothelial cells, dermal fibroblasts, peripheral blood mononuclear cells, or the cell lines U937, HL-60, K562 or Mo7E; it does react with the primitive myeloid cell line KG-1. mAb MS-1 immunoprecipitates a major protein of 215 kD and minor proteins of 320 and 120 kD from splenic extracts as analyzed by SDS-PAGE with reduction. These proteins are soluble in aqueous buffers. Immunoprecipitation from KG-1 cell lysates detects four proteins of 280, 300, 205, and 120 kD; the 300-, 205-, and 120-kD species, presumably corresponding to the 320-, 215-, and 120-kD species in spleen, respectively, are secreted into the media. Under nonreducing conditions, immunoprecipitates from KG-1 cell lysates or conditioned media contain one predominant 300-kD species; upon isolation and reduction, this 300-kD species separates into the previously observed 300-, 205-, and 120-kD species. Pulse-chase experiments and limited proteolysis peptide mapping suggest that the 280-kD species is a precursor of the mature 300-kD species which may be subsequently cleaved to yield the 205- and 120-kD species. Because of its size, solubility and expression pattern, the antigen recognized by mAb MS-1 is likely to be an extracellular matrix protein utilized by endothelial cells of contorted, large caliber, or leaky microvessels that lack a well-formed basement membrane.

An in vitro study of the antimicrobial activity of some endodontic medicaments and their bases using an agar well diffusion assay.

BACKGROUND: The aim of this study was to determine the in vitro antimicrobial activities of various endodontic medicaments and their bases against selected organisms using an agar diffusion assay. METHODS: An agar well diffusion assay was used to test the antimicrobial action of some commonly used endodontic medicaments (Ledermix paste, Pulpdent paste, Ultracal paste, and a 50:50 mix of Ledermix and Pulpdent pastes) and their bases. Three bacterial species (E. faecalis, P. micros, P. intermedia) and one yeast (C. albicans) were selected. The diameters of growth inhibition zones and pH were assessed. RESULTS: P. micros demonstrated the highest level of in vitro resistance. Pulpdent and Ultracal pastes had the highest pH (12.64 and 12.53, respectively). The addition of Pulpdent to Ledermix did not increase the zone sizes significantly. CONCLUSIONS: All the commercial products showed some in vitro antimicrobial activity. Ledermix paste and the 50:50 Ledermix/Pulpdent mixture being the most effective in this model. The known anti-inflammatory/analgesic properties of Ledermix and the results from this agar model suggest that the 50:50 Ledermix/Pulpdent combination would be the preferred medicament for clinical use in symptomatic cases, even though the addition of calcium hydroxide to Ledermix did not appear to be synergistic in terms of enhancing the antimicrobial action.

Prevention and caries risk management in teenage and orthodontic patients.

As patients progress from childhood through to teenage years, they progress through periods of high caries risk as they undergo changes in lifestyle and oral microflora. Removable or fixed orthodontic treatment also alters the oral microflora and can dramatically increase caries risk. This paper outlines ways to identify the transition to higher caries risk, and practical ways to lower the risk of hard tissue loss from dental caries during orthodontic treatment across the teenage years, including tooth surface protection, optimised use of mechanical and chemical plaque control, and appropriate delivery of remineralising agents over time.