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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

Is there a consensus on antibiotic usage for dental implant placement in healthy patients?

This systematic review aimed to determine whether there is consensus for antibiotic prescription in healthy patients undergoing implant placement. A search of PubMed, Embase and Medline databases was conducted in January 2016 to find published journal articles on the use of antibiotics in implant placement, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The inclusion criteria were prospective human clinical trials investigating antibiotic usage during implant placement. Fifteen studies were deemed suitable. In 13 studies, no statistical difference was found between antibiotic use and the incidence of prosthetic failure, implant failure and early postoperative infections. These were rated as having low to high risk bias. Contrary results were reported in two studies, both of which were rated as having a high potential for bias. In conclusion, antibiotic use in healthy patients for the prophylaxis of surgical infection associated with dental implant placement does not appear to improve clinical outcomes. Practitioners should apply principles of antimicrobial stewardship and not use antibiotics as a routine measure in healthy patients.

Minimal intervention management of the older patient.

With an aging population, dentists need to be aware of the risks which come to their elderly patients from retained teeth and exposed root surfaces. Oral health problems in the later years of life are multifactorial, with lifestyle, plaque and salivary factors remaining paramount. Root surface caries is likely to present a challenge in patients with a strong history of past coronal caries (and who have the attendant lifestyle risk factors) as well as in elderly patients who suddenly develop salivary hypofunction. Following a maximum interception approach means that specific efforts are needed to profile salivary, plaque and lifestyle risk factors and ensure that the dentition can be cleaned by the patient and maintained in a way which gives comfort and function as well as aesthetics. Discussions around long-term objectives for oral health are important when there is a sudden decline in general health in the later years of life. It may be appropriate to use tooth surface protection for strategic anterior teeth and apply the shortened dental arch concept where patients cannot readily maintain their own oral health because of frailty or medical conditions. Glass ionomer materials can be used both for root surface protection and for conservative restoration where a minimally invasive preparation has been undertaken. In other cases, arrest of lesions using silver fluoride or CPP-ACP topical treatments can delay or obviate the need for restorative interventions, and forms part of the management of patients in high care units in nursing homes. Involving all members of the healthcare team in supporting oral health is an important strategy to ensure that oral health issues are not overlooked. The challenge is to promote evidence-based self-care. A key message is to promote oral health as part of overall health.

Violet and blue light-induced green fluorescence emissions from dental caries.

BACKGROUND: The objective of this laboratory study was to compare violet and visible blue LED light-elicited green fluorescence emissions from enamel and dentine in healthy or carious states. METHODS: Microscopic digital photography was undertaken using violet and blue LED illumination (405 nm and 455 nm wavelengths) of tooth surfaces, which were photographed through a custom-made stack of green compensating filters which removed the excitation light and allowed green fluorescence emissions to pass. Green channel pixel data were analysed. RESULTS: Dry sound enamel and sound root surfaces showed strong green fluorescence when excited by violet or blue lights. Regions of cavitated dental caries gave lower green fluorescence, and this was similar whether the dentine in the lesions was the same colour as normal dentine or was darkly coloured. The presence of saliva on the surface did not significantly change the green fluorescence, while the presence of blood diluted in saliva depressed green fluorescence. CONCLUSIONS: Using violet or blue illumination in combination with green compensating filters could potentially aid in the assessment of areas of mineral loss.

A Longitudinal Observational Study of Developmental Defects of Enamel from Birth to 6 Years of Age.

Developmental defects of the enamel (DDE) commonly occur in the primary dentition. Although several cross-sectional studies have shown the association of DDE with caries, there is a paucity of longitudinal studies demonstrating that teeth with DDE are at greater risk of caries than are normal teeth. Therefore, the aim of the present study was to longitudinally track a total of 14,220 primary teeth in 725 children from a large birth cohort study, who were interviewed by telephone or home visits at 6-mo intervals. There were 74 children with at least 1 tooth with DDE. We compared teeth with and without DDE by calculating hazard ratios for caries using a Cox proportional hazards model and by plotting caries-free probabilities by child's age for DDE categories in a Kaplan-Meier plot. Our results show that teeth with DDE had a much higher risk for caries and developed caries earlier than did teeth without DDE. The hazard ratios (95% confidence intervals) for caries were 6.0 (2.4 to 14.6; P < 0.001) for pits, 5.5 (3.8 to 7.8; P < 0.001) for missing enamel, and 4.5 (1.8 to 11.3; P < 0.002) for hypoplasia occurring with yellow-brown opacities. Kaplan-Meier survival plots of caries-free probabilities by age, depending on DDE type, suggest that all types of enamel hypoplasia are associated with a statistically significant increased risk for caries. The study provides longitudinal evidence that DDE are a strong determinant for caries in the primary dentition (ACTRN No. 012606000356561). Knowledge Transfer Statement: The study provides longitudinal evidence that developmental defects of enamel of the primary dentition are strongly associated with increased risk of early childhood caries.

Inhibitory effects of antiseptic mouthrinses on Streptococcus mutans, Streptococcus sanguinis and Lactobacillus acidophilus.

BACKGROUND: Oral antiseptics are valuable in controlling oral infections caused by cariogenic bacteria. The aim of this study was to investigate the effects of mouthrinses and pure antiseptic compounds on Streptococcus mutans and non-mutans bacteria (Streptococcus sanguinis and Lactobacillus acidophilus). METHODS: The agar diffusion assay was employed to determine bacterial growth inhibition. RESULTS: Commercial mouthrinses containing chlorhexidine gluconate (0.2%), cetylpyridinium chloride (0.05%) and sodium fluoride (0.05%) produced statistically similar growth inhibition of S. mutans, S. sanguinis and L. acidophilus (with zones of inhibition ranging from 7.56 ± 0.52 mm to 7.39 ± 0.53 mm, 17.44 ± 0.94 mm to 18.31 ± 0.62 mm and 8.61 ± 1.43 to 8.67 ± 1.43 mm respectively, p > 0.05). The chlorhexidine mouthwash produced the greatest mean growth inhibition of S. sanguinis and S. mutans compared to all other mouthrinses tested (p < 0.01). The minimum concentrations at which inhibition against S. mutans could be detected were chlorhexidine gluconate at 0.005% (wt/vol), cetylpyridinium chloride 0.01% (wt/ vol), povidone iodine 10% (wt/vol) and sodium hypochlorite 0.5% (vol/vol). CONCLUSIONS: Chlorhexidine (0.01%), cetylpyridinium chloride (0.01%), povidone iodine (10%) and sodium hypochlorite (0.5%) are effective at inhibiting the growth of S. mutans, S. sanguinis and L. acidophilus.

Evaluation and prevention of enamel surface damage during dental restorative procedures.

BACKGROUND: This study examined the effect of operator experience, dominance, tooth position and access, on frequency and extent of iatrogenic damage to approximal tooth surfaces during conventional Class II cavity preparations. The effectiveness of protective devices in minimizing damage was also explored. METHODS: 10 students and 10 experienced dentists each prepared 24 Class II cavity preparations in typodont teeth without protection; 10 utilizing stainless steel matrix bands and 10 utilizing protective wedges. The frequency and extent of damage were analysed with respect to the above variables. Subsequently, 20 natural and 20 typodont teeth were utilized to establish the relationship in depth of damage caused by a high-speed diamond bur on typodont versus natural teeth. RESULTS: Dentists caused iatrogenic damage on 74% of approximal surfaces without protection, which fell to 50% and 46% respectively when matrix bands and wedges were used as guards. The corresponding rates of damage for students were 94%, 80% and 44%. There was no difference in depth of damage caused on the two types of teeth when bur was in contact with teeth for a very short time. CONCLUSIONS: Greater operator experience and the use of guards reduces iatrogenic damage to proximal surfaces during preparation with high-speed rotary instruments.

Antibacterial activity of fluoride compounds and herbal toothpastes on Streptococcus mutans: an in vitro study.

BACKGROUND: Streptococcus mutans is an important bacterial species implicated in dental caries. This laboratory study compared the antimicrobial activity of a number of fluoride containing and herbal dentifrices and their components against S. mutans. METHODS: An agar diffusion method was used with Mueller-Hinton agar. Wells were filled with either 10 commercial fluoride or 6 herbal dentifrices, or with solutions of various fluoride compounds, sodium lauryl sulphate, sodium benzoate, chlorhexidine digluconate or triclosan. Diameters of zones of bacterial growth inhibition surrounding the wells were measured using a micrometer. RESULTS: Significant differences were found for growth inhibition between the 10 fluoridated dentifrices (p < 0.0001), with Colgate Total having the greatest effect. There was not a direct correlation with fluoride type or fluoride concentration. The antibacterial activities of the 6 herbal toothpastes varied, with Herbal Fresh being the strongest. Sodium lauryl sulphate showed strong antimicrobial activity against S. mutans at the levels used in dentifrices. CONCLUSIONS: Antimicrobial activity of commercial dentifrices against S. mutans may be exerted by components other than fluoride. Ingredients such as triclosan and sodium lauryl sulphate have larger antimicrobial effects than fluorides in this model.