Diet changes due to urbanization in South Africa are linked to microbiome and metabolome signatures of Westernization and colorectal cancer.

Transition from traditional high-fiber to Western diets in urbanizing communities of Sub-Saharan Africa is associated with increased risk of non-communicable diseases (NCD), exemplified by colorectal cancer (CRC) risk. To investigate how urbanization gives rise to microbial patterns that may be amenable by dietary intervention, we analyzed diet intake, fecal 16 S bacteriome, virome, and metabolome in a cross-sectional study in healthy rural and urban Xhosa people (South Africa). Urban Xhosa individuals had higher intakes of energy (urban: 3,578 ± 455; rural: 2,185 ± 179 kcal/d), fat and animal protein. This was associated with lower fecal bacteriome diversity and a shift from genera favoring degradation of complex carbohydrates (e.g., Prevotella) to taxa previously shown to be associated with bile acid metabolism and CRC. Urban Xhosa individuals had higher fecal levels of deoxycholic acid, shown to be associated with higher CRC risk, but similar short-chain fatty acid concentrations compared with rural individuals. Fecal virome composition was associated with distinct gut bacterial communities across urbanization, characterized by different dominant host bacteria (urban: Bacteriodota; rural: unassigned taxa) and variable correlation with fecal metabolites and dietary nutrients. Food and skin microbiota samples showed compositional differences along the urbanization gradient. Rural-urban dietary transition in South Africa is linked to major changes in the gut microbiome and metabolome. Further studies are needed to prove cause and identify whether restoration of specific components of the traditional diet will arrest the accelerating rise in NCDs in Sub-Saharan Africa.

Cerebriform sebaceous nevus: a subtype of organoid nevus due to specific postzygotic FGFR2 mutations.

BACKGROUND: Postzygotic mutations in FGFR2 have been identified in mosaic forms of acne, keratinocytic epidermal nevi, nevoid acanthosis nigricans / rounded and velvety epidermal nevus and in two fetuses with papillomatous pedunculated sebaceous nevus (PPSN). OBJECTIVES: To determine the clinical and genetic characteristics of children with cerebriform, papillomatous and pedunculated variants of sebaceous nevi. METHODS: Infants diagnosed with sebaceous nevi characterized by a cerebriform, papillomatous and/or pedunculated morphology over a 10-year period (2010-2019) at three paediatric dermatology centres in Switzerland and France were included in this case series. Clinical and histological characteristics were assessed. Next-generation sequencing was used to assess for FGFR2 mutations. RESULTS: All nevi were located on the head, with a rounded or linear shape and a typical cerebriform, sometimes papillomatous and pedunculated, surface. No associated extracutaneous anomalies were found. Nevi harboured postzygotic mutations in the transmembrane domain of FGFR2 in 6/8 children (75%), either the known specific p.(Cys382Arg) mutation in 5 cases, or a novel mutation, p.(Val395Asp), in one. CONCLUSIONS: We found an exquisite genotype-phenotype correlation in these rare nevi, with specific postzygotic mutations in the transmembrane domain of FGFR2. As not all lesions were truly papillomatous and pedunculated, the term cerebriform sebaceous nevus (CSN) appears more suitable than PPSN to describe this entity. The cerebriform pattern of CSN is reminiscent of cutis gyrata, as seen in Beare-Stevenson syndrome, which is caused by closely related germline FGFR2 mutations. While clinically impressive, CSN seem to carry a good prognosis and a low risk for extracutaneous associations.

Skin-related quality of life in children and adolescents with congenital melanocytic naevi - an analysis of self- and parent reports.

BACKGROUND: Congenital melanocytic naevi (CMN) may affect patient quality of life (QoL) due to medical complications (development of malignant melanoma or involvement of the central nervous system), skin-related discomfort or psychosocial sequelae. OBJECTIVES: To analyse skin-related QoL in children and adolescents with CMN and to identify predictors of low QoL. METHODS: Worldwide recruitment of participants through patient support groups. Data collection through a Web-based survey. QoL was assessed using the Children's Dermatology Life Quality Index© (CDLQI). Demographic and CMN-related characteristics were examined as possible predictors of impaired QoL. RESULTS: A total of 135 proxy reports for children affected by CMN aged 4-18 years (M = 9.34 years, SD = 4.16 years) and 28 self-reports of adolescents aged 14-18 years (M = 16.3 years, SD = 1.2 years) were included. The mean CDLQI score was 4.00 (SD = 4.39) for proxy reports and 6.89 (SD = 5.85) for self-reports. Most parents (76%) reported 'no' or a 'small' impact, 19% a 'moderate' and 5% a 'very large' or 'extremely large' impact on their child's QoL. In self-reports, 46% of the adolescents reported 'no' or a 'small impact', 43% a 'moderate' and 11% a 'very large' or 'extremely large' impact. Visible CMN location, malignant melanoma and higher child's age were important predictors of QoL impairments. CONCLUSIONS: Most CMN have a modest effect on QoL. However, there is large variability with a significant proportion of adolescents experiencing a moderate-to-large impact on QoL in contrast to children. Healthcare professionals should be aware of the predictors of QoL in children with CMN.

A Near Visual Acuity Test for Dentists.

Unimpaired near vision is crucial in dentistry, but appropriate visual tests at dental working distance are not publicly available. The aim of this study was to validate a novel visual triage test for dentists that is easy to use and freely available. The near visual acuity at 300 mm of 106 dental professionals (aged 21-65 years) was assessed with 1) a validated near visual test for scientific purposes miniaturized on a microfilm; 2) an experimental test using a US $5 bill, in which the first five words of each line in the Lincoln Memorial frieze had to be read under a dental operating light. The Spearman rank correlation coefficient of 0.784 revealed a strong correlation between the two tests (p<0.0001). The ability to read six or more words in the memorial frieze meant there was a 94% chance of having a validated near visual acuity greater than or equal to the median score of the dentists tested. If none of the words could be read, the chance of having a near visual acuity below the median of the peer group was 89%. The influence of the dentists' age and experience on their visual performance reported in former studies was corroborated with this new test. The US $5 bill offers a simple and easily available near visual test to rank individuals' near vision relative to that of other dentists and to recognize the progression of presbyopia with increasing age.

Apical filling characteristics of carrier-based techniques vs. single cone technique in curved root canals.

OBJECTIVES: In this in vitro study, we assessed filling characteristics (adaptation, homogeneity, sealer percentage, position of the carrier) of warm and cold obturation methods in curved root canals. MATERIALS AND METHODS: A reciprocating method was used to prepare 90 curved roots (25 ° average curvature) to an apical size of 25.08. They were then obturated with either (A) Guttafusion (VDW, Munich, Germany), (B) Thermafil (Maillefer, Ballaigues, Switzerland) or (C) single cone technique using 25.08 gutta-percha (VDW) and sealer (2Seal easymix) (n = 30 each group). Five sections in 1-mm steps were obtained from each root, beginning 1 mm short of the apex. The percentage of voids in contact with root canal walls (PVO), the proportion of voids per area (PVA) and the percentage of sealer per area (PSA) were measured. RESULTS: Little to no differences between Guttafusion and Thermafil were seen in curved root canals with respect to adaptation and homogeneity in the apical region. Both methods showed significantly better adaptation and homogeneity than the single cone technique. The proportion of sealer was significantly greater when roots were obturated with Guttafusion than with Thermafil, but both warm obturation techniques had significantly smaller sealer areas than the single cone technique. CONCLUSIONS: Compared to the single cone technique, a more favourable root canal filling with less sealer could be expected from both warm obturation techniques in curved root canals. CLINICAL RELEVANCE: The easier-to-handle Guttafusion leads to comparable results as Thermafil in curved root canals.

Impact of different magnification levels on visual caries detection with ICDAS.

OBJECTIVES: The aim of this in vitro study was to examine the effect of different levels of magnification on the accuracy and reliability of visual caries detection using ICDAS criteria. METHODS: Occlusal surfaces of 100 extracted molars were assessed by 14 examiners (3rd and the 4th year dental students and dentists) using no magnification aids, a 2.5× Galilean loupe, a 4.5× Keplerian loupe, or a surgical microscope with 10× magnification. The assessments were repeated on a different day. Sensitivity, specificity, AUC and reliabilities were calculated according to the gold standard of histology. RESULTS: We found that with increasing magnification, the number of surfaces rated as "sound" (ICDAS code 0) decreased, while the number of surfaces with a localized enamel breakdown (ICDAS code 3) increased. While the sensitivities increased, the values of the specificities decreased to an unacceptably low level irrespective of the clinical experience of the examiners. CONCLUSIONS: ICDAS seems to be optimized for natural vision up to 2.0× magnification and not for high magnifications. The use of powerful magnification in visual caries detection involves the risk of unnecessary and premature invasive treatment. CLINICAL SIGNIFICANCE: This paper discusses when it does and does not make sense to use magnification devices for visual caries detection using ICDAS criteria. Strong magnifications should be refrained from for this purpose.

The impact of loupes and microscopes on vision in endodontics.

AIM: To report on an intraradicular visual test in a simulated clinical setting under different optical conditions. METHODOLOGY: Miniaturized visual tests with E-optotypes (bar distance from 0.01 to 0.05 mm) were fixed inside the root canal system of an extracted maxillary molar at different locations: at the orifice, a depth of 5 mm and the apex. The tooth was mounted in a phantom head for a simulated clinical setting. Unaided vision was compared with Galilean loupes (2.5× magnification) with integrated light source and an operating microscope (6× magnification). The influence of the dentists' age within two groups was evaluated: <40 years (n = 9) and ≥40 years (n = 15). RESULTS: Some younger dentists were able to identify the E-optotypes at the orifice, but otherwise, natural vision did not reveal any measurable result. With Galilean loupes, the younger dentists <40 years could see a 0.05 mm structure at the root canal orifice, in contrast to the older group ≥40 years. Only the microscope allowed the observation of structures inside the root canal, independent of age. CONCLUSION: Unaided vision and Galilean loupes with an integrated light source could not provide any measurable vision inside the root canal, but younger dentists <40 years could detect with Galilean loupes a canal orifice corresponding to the tip of the smallest endodontic instruments. Dentists over 40 years of age were dependent on the microscope to inspect the root canal system.

[Congenital nevi in childhood]. / Kongenitale Nävi im Kindesalter.

Nevi represent congenital hamartomatous malformations of various components of the skin. The most common forms are congenital melanocytic nevi (CMN) and nevi of epithelial origin (epidermal and organoid nevi). Large CMN in particular can lead to severe complications and the management of those affected represents a challenge from birth. In contrast to previous assumptions, the risk of malignancy from CMN is considered to be relatively low however, this may be relevantly increased in certain situations. Possible extracutaneous symptoms in cases of central nervous system (CNS) involvement should not be underestimated and early imaging investigations are part of the routine diagnostic procedure. Surgical measures are still very important in the treatment of CMN but the indications must be weighed up for each individual case. Patients often experience marked stigmatization due to disfigurement by their birthmark and this needs to be taken into consideration for their treatment. The most common epithelial nevi are sebaceous nevi. In 2-13 % of cases additional tumors occur within this nevus and early surgical excision is indicated in most cases, not least for aesthetic reasons. If generalized spreading of epidermal nevi occurs, additional investigations are necessary to exclude associated ophthalmological, cardiac or neurological malformations.

Infiltration of natural caries lesions in relation to their activity status and acid pretreatment in vitro.

This study aimed at testing how active and inactive enamel caries lesions differ by their degree of resin infiltration, and whether the choice of acid pretreatment plays a crucial role. Four examiners assessed 104 human molars and premolars with noncavitated enamel lesions and classified them as 'active' or 'inactive' using the Nyvad criteria. Forty-five teeth were included in this study after independent unanimous lesion activity assessment. Lesions were cut perpendicularly into 2 halves. Each half lesion was pretreated with either 15% hydrochloric acid or 35% phosphoric acid. The lesions were infiltrated after staining with rhodamine isothiocyanate. Thin sections of 100 µm were prepared and the specimens were bleached with 30% hydrogen peroxide. The specimens were then counterstained with sodium fluorescein, subjected to confocal laser scanning microscopy and analyzed quantitatively. Outcome parameters were maximum and average infiltration depths as well as relative penetration depths and areas. In active lesions no significant difference of percentage maximum penetration depth and percentage average penetration depth between lesions pretreated with hydrochloric or phosphoric acid could be observed. In inactive lesions, however, phosphoric acid pretreatment resulted in significantly lower penetration compared to hydrochloric acid pretreatment. Surface conditioning with hydrochloric acid led to similar infiltration results in active and inactive lesions. Moreover, inactive lesions showed greater variability in all assessed infiltration parameters than did active lesions. In conclusion, caries lesion activity and acid pretreatment both influenced the infiltration. The use of phosphoric acid to increase permeability of the surface layer of active lesions should be further explored.

Detection of proximal secondary caries at cervical class II-amalgam restoration margins in vitro.

OBJECTIVES: To compare the performance of LFpen (DIAGNOdent pen) with two different wedge-shaped tips to conventional bitewing radiography (BW) for detecting proximal secondary caries at the cervical margin of amalgam restorations in vitro. METHODS: Seventy-five molars with class II amalgam restorations were selected. Depending on the marginal filling extension, data was subdivided into a crown group (C), when the filling ended in enamel, and into a root group (R), when the filling ended beyond the cementum-enamel junction. Bayesian analysis including calculation of the area under the receiver operating curve (AUC) was performed. Furthermore, Spearman correlations between caries and cofactors, such as presence of plaque or stain, occlusal ditching, marginal gap size, filling overhangs, and shortfalls, were calculated. Additionally, for group R the correlation coefficient between LFpen measurements and lesion depth was calculated. Histology served as gold standard. RESULTS: In group C both at the D1 and D3 levels, LFpen with two different tips showed a better performance than bitewing radiography (AUC at D1: 0.83/0.79 (LFpen) and 0.63 (BW); at D3: 0.66/0.66 (LFpen) and 0.53 (BW)). In group R, the respective AUC values were 0.53/0.56 (LF) and 0.59 (BW). A significant medium correlation was observed for occlusal ditching and proximal caries. Stain accumulation at the restoration margins especially in combination with filling overhangs interfered with LFpen readings, resulting in false positive measurements. CONCLUSIONS: Compared to BW, LFpen enhances the detection of secondary caries lesions at the cervical margin of amalgam restorations that do not extend below the cementum-enamel junction.

Pericardial effusion of HIV-infected patients ? Results of a prospective multicenter cohort study in the era of antiretroviral therapy.

BACKGROUND: Patients with human immunodeficiency virus (HIV) infection have an increased risk of cardiovascular diseases. Previous publications described pericardial effusion as one of the most common HIV-associated cardiac affiliations. The aim of the current study was to investigate if pericardial effusion still has a relevant meaning of HIV-infected patients in the era of antiretroviral therapy. METHODS: The HIV-HEART (HIV-infection and HEART disease) study is a cardiology driven, prospective and multicenter cohort study. Outpatients with a known HIV-infection were recruited during a 20-month period in a consecutive manner from September 2004 to May 2006. The study comprehend classic parameters of HIV-infection, comprising CD4-cell count (cluster of differentiation) and virus load, as well as non-invasive tests of cardiac diseases, including a thorough transthoracic echocardiography. RESULTS: 802 HIV-infected patients (female: 16.6%) with a mean age of 44.2 ± 10.3 years, were included. Duration of HIV-infection since initial diagnosis was 7.6 ± 5.8 years. Of all participants, 85.2% received antiretroviral therapy. Virus load was detectable in 34.4% and CD4 - cell count was in 12.4% less than 200 cells/µl. Pericardial effusions were present in only two patients of the analysed population. None of the participants had signs of a relevant cardiovascular impairment by pericardial effusion. CONCLUSIONS: Our results demonstrate that the era of antiretroviral therapy goes along with low rates of pericardial effusions in HIV-infected outpatients. Our findings are in contrast to the results of publications, performed before the common use of antiretroviral therapy.

Evaluation of perpendicular reflection intensity for assessment of caries lesion activity/inactivity.

The aim of this study was to evaluate, using visual assessment, an experimental optical sensor measuring perpendicular reflection intensity (PRI) as an indicator of enamel caries lesion activity/inactivity. Forty teeth with either an active or an inactive enamel lesion were selected from a pool of extracted teeth. Each tooth was cut into halves, with a clinically sound half and a half with a non-cavitated enamel lesion. After gentle plaque removal, the teeth were kept moistened. The lesions were then photographed and a defined measuring site per lesion was chosen and indicated with an arrow on a printout. Independently, the chosen site was visually assessed for lesion activity, and its glossiness was measured with PRI assessment. Surface roughness (SR) was assessed with optical profilometry using a confocal microscope. Visual assessment and PRI were repeated after several weeks and a reliability analysis was performed. For enamel lesions visually scored as active versus inactive, significantly different values were obtained with both PRI and SR. PRI values of the clinically sound control surfaces were significantly different only from active lesions. Generally, inactive lesions had the same glossiness and the same roughness as the sound control surfaces. The reliabilities for visual assessment (κ = 0.89) and for PRI (ICC = 0.86) were high. It is concluded that, within the limits of this study, PRI can be regarded as a promising tool for quantitative enamel lesion activity assessment. There is scope and potential for the PRI device to be considerably improved for in vivo use.

Osmotic expanders in children: no filling--no control--no problem?

BACKGROUND: Self-filling, hydrogel-based osmotic tissue expanders have been successfully used for several years, mainly in adult patients. We wanted to test this novel device in pediatric plastic and reconstructive surgery. MATERIAL AND METHODS: Between November 2004 and September 2009, we implanted 53 osmotic tissue expanders following standard surgical principles in a total of 30 children and adolescents with burn scars, congenital nevi, alopecia, or foot deformities. RESULTS: All expanders reached their predicted volume within 6 weeks and 51 (96.2%) produced a sufficient amount of additional skin for the intended coverage of the defect. A serious infection precluding the planned reconstructive procedure occurred with 2 expanders (3.8%). Minor complications occurred at 6 implantation sites (11.4%), and consisted of small necrotic areas and perforations (n = 3) and minor infections (n = 3). These problems could be controlled and did not interfere with the subsequent plasty. The final results recorded at the last follow-up (mean: 21 months, range: 9-48 months) were rated as excellent in 25, good in 19, moderate in 6, and poor in 1 patient. CONCLUSION: This is apparently the largest pediatric series in which self-filling expanders have been used. The data obtained indicates that self-filling expanders can be safely and effectively used for various plastic, reconstructive and orthopedic procedures in children and adolescents. The fact that numerous painful and distressing filling sessions are obviated with these expanders is particularly beneficial for those children too young to understand and cooperate. Moreover, this approach minimizes the risk of infection and lowers costs.

Novel treatment for massive lower extremity avulsion injuries in children: slow, but effective with good cosmesis.

BACKGROUND: Extended avulsion injuries are associated with significant loss of skin and subcutaneous fat, leaving the reconstructive surgeon with the challenge of substituting all tissues lost in the best possible way. We wanted to test whether the combined use of a Vacuum Assisted Closure system (VAC) and Integra Dermal Regeneration Template (IDRT) matched the required treatment profile encompassing initial control of infection, remodeling of body contours, and reconstruction of near normal skin. MATERIALS AND METHODS: 4 children with massive lower extremity avulsion injuries were treated with early necrosectomy, VAC application for 3-5 weeks for wound cleansing and wound bed conditioning, subsequent implantation of IDRT, and finally autologous split thickness skin grafting (STSG) for definitive wound closure. Thereafter, a standard rehabilitation program was used. The key parameters of VAC and IDRT application, take rates of IDRT and STSG, complications, length of stay, and final outcome were recorded. RESULTS: In all patients, early removal of necrosis and infection control was successfully achieved. Continuous VAC application fostered the formation of a several millimeters thick new tissue layer partly compensating for the lost hypodermis. IDRT implantation and subsequent STSG yielded take rates of nearly 100% and both functionally and cosmetically excellent long-term results. There were no major complications. CONCLUSION: The combination of VAC and IDRT in children with massive leg avulsion injuries is feasible, safe, and delivers high-quality long-term outcomes that appear to justify the multiple operative procedures, the long hospitalization times, and the comparatively high costs entailed.

Preventing erosion with novel agents.

OBJECTIVES: This in vitro study aimed to investigate the protective effect of four commercial novel agents against erosion. METHODS: Ninety human molars were distributed into 9 groups, and after incubation in human saliva for 2 h, a pellicle was formed. Subsequently, the specimens were submitted to demineralization (orange juice, pH 3.6, 3 min) and remineralization (paste slurry containing one of the tested novel agents, 3 min) cycles, two times per day, for 4 days. The tested agents were: (1) DenShield Tooth; active ingredient: 7.5% W/W NovaMin(®) (calcium sodium phosphosilicate); (2) Nanosensitive hca; active ingredient: 7.5% W/W NovaMin(®); (3) GC Tooth Mousse; active ingredient: 10% Recaldent™ (CPP-ACP); (4) GC MI Paste Plus; active ingredients: 10% Recaldent™, 900 ppm fluoride. Two experimental procedures were performed: in procedure 1, the tested agents were applied prior to the erosive attack, and in procedure 2 after the erosive attack. A control group receiving no prophylactic treatment was included. Surface nanohardness (SNH) of enamel specimens was measured after pellicle formation and after completion of daily cyclic treatment. RESULTS: SNH significantly decreased at the end of the experiment for all groups (p<0.05). In both procedures, there was no statistically significant difference between the control group and those treated with paste slurries (p>0.05). In addition, the changes in SNH (ΔSNH=SNHbaseline-SNHfinal) did not show statistically significant difference between both procedures (p>0.05). CONCLUSION: Tooth erosion cannot be prevented or repaired by these novel agents, regardless of fluoride content.

In vivo performance of a laser fluorescence device for the approximal detection of caries in permanent molars.

OBJECTIVES: The aim of this randomised clinical trial was to investigate if a laser fluorescence device is able to discriminate between sound and carious approximal sites and between enamel and dentinal lesions, as well as to find appropriate cut-off values. METHODS: One hundred and seventeen sound or uncavitated carious sites in permanent molars were visually and radiographically examined, then either opened or not, after which their laser fluorescence was measured. Forty-three lesions were opened, the caries removed and the clinically identified caries depths were registered in addition to the radiographical scoring. Seventy-four sites were radiographically deemed sound or had enamel caries and were not opened. Here, the radiographical scorings were registered. RESULTS: Taking the radiographic scoring as gold standard for all investigated approximal sites, sound sites (D(0), n=40) showed significantly lower laser fluorescence measurements than carious sites (D(1-4), n=77) (Mann-Whitney test, P<0.025) suggesting a cut-off at 7 (sensitivity=0.68, specificity=0.7). Comparing measurements of D(0-2) (n=74) and D(3,4) (n=43), the results were also different by a statistically significant amount (P<0.025) and the cut-off calculated to be 16 (sensitivity=0.6, specificity=0.84). A fair positive correlation between laser fluorescence values and radiographical scoring was found (rho=+0.47, P<0.01). Analysing the 43 opened lesions with their clinically found lesion depths as gold standard, there was a fair positive correlation to the laser fluorescence values (rho=+0.34, P=0.03) and a moderately strong correlation to the radiographic scoring (rho=+0.67, P<0.01). CONCLUSION: The device may be an adjunct tool in the approximal detection of caries along with established procedures.

Potent antilisterial cell-free supernatants produced by complex red-smear cheese microbial consortia.

The microbial surface ripening consortia of 49 soft cheeses were investigated with respect to their inhibition of Listeria monocytogenes. When L. monocytogenes EGDe (serovar 1/2a) was cultivated in cell-free supernatants obtained from consortia grown for 8 h in liquid medium, a strong bactericidal activity was observed in several cases. The cell-free supernatants of 2 of these consortia (I and II) reduced an initial L. monocytogenes inoculum of 5 × 10(7) cfu/mL to zero after 24 h of incubation. No inhibitory substances could be washed off the complex consortia when incubated for a 10-min period. A taxonomical analysis of the antilisterial consortia I and II using Fourier transform infrared spectroscopy yielded a considerable species diversity, with lactic acid bacteria increasing strongly during the 8-h cultivation. Therefore, 23 lactic acid bacteria bacteriocin genes were assayed using specific PCR primers, identifying 3 bacteriocin genes in both microbial communities. However, no transcription of these genes was found on cheese surfaces or in consortia propagated in liquid culture. Individual lactic acid bacteria isolates of consortia I and II displayed no or only weak inhibition of L. monocytogenes on solid medium. The complex cell-free supernatants I and II, in contrast, exhibited an unusually broad inhibitory spectrum, killing L. monocytogenes ssp., Bacillus spp., Staphylococcus aureus, as well as gram-negative bacteria such as Escherichia coli DH5α and Salmonella enterica serovar Typhimurium. Inhibition could not be abolished by heating to 100°C or by proteinase K treatment. Initial purification of an inhibitory substance from consortium I by solid-phase extraction and HPLC indicates the presence of rather small, extremely stable compounds, which, most probably, are not bacteriocins.

Traditional lesion detection aids.

Lesion detection aids ideally aim at increasing the sensitivity of visual caries detection without trading off too much in terms of specificity. The use of a dental probe (explorer), bitewing radiography and fibre-optic transillumination (FOTI) have long been recommended for this purpose. Today, probing of suspected lesions in the sense of checking the 'stickiness' is regarded as obsolete, since it achieves no gain of sensitivity and might cause irreversible tooth damage. Bitewing radiography helps to detect lesions that are otherwise hidden from visual examination, and it should therefore be applied to a new patient. The diagnostic performance of radiography at approximal and occlusal sites is different, as this relates to the 3-dimensional anatomy of the tooth at these sites. However, treatment decisions have to take more into account than just lesion extension. Bitewing radiography provides additional information for the decision-making process that mainly relies on the visual and clinical findings. FOTI is a quick and inexpensive method which can enhance visual examination of all tooth surfaces. Both radiography and FOTI can improve the sensitivity of caries detection, but require sufficient training and experience to interpret information correctly. Radiography also carries the burden of the risks and legislation associated with using ionizing radiation in a health setting and should be repeated at intervals guided by the individual patient's caries risk. Lesion detection aids can assist in the longitudinal monitoring of the behaviour of initial lesions.

Novel lesion detection aids.

Several non-invasive and novel aids for the detection of (and in some cases monitoring of) caries lesions have been introduced in the field of 'caries diagnostics' over the last 15 years. This chapter focusses on those available to dentists at the time of writing; continuing research is bound to lead to further developments in the coming years. Laser fluorescence is based on measurements of back-scattered fluorescence of a 655-nm light source. It enhances occlusal and (potentially) approximal lesion detection and enables semi-quantitative caries monitoring. Systematic reviews have identified false-positive results as a limitation. Quantitative light-induced fluorescence is another sensitive method to quantitatively detect and measure mineral loss both in enamel and some dentine lesions; again, the trade-offs with lower specificity when compared with clinical visual detection must be considered. Subtraction radiography is based on the principle of digitally superimposing two radiographs with exactly the same projection geometry. This method is applicable for approximal surfaces and occlusal caries involving dentine but is not yet widely available. Electrical caries measurements gather either site-specific or surface-specific information of teeth and tooth structure. Fixed-frequency devices perform best for occlusal dentine caries but the method has also shown promise for lesions in enamel and other tooth surfaces with multi-frequency approaches. All methods require further research and further validation in well-designed clinical trials. In the future, they could have useful applications in clinical practice as part of a personalized, comprehensive caries management system.