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Visual color determination is part of the daily routine in dental practice. However, it is not a part of dental education so far. The aim of this study was to evaluate whether visual or digital tooth color determination of 3D-printed teeth is a reliable tool for inexperienced dentistry students. Preclinical dental students evaluated eleven 3D-printed, tooth-shaped samples (VarseoSmile Crown plus, BEGO, Bremen, Germany) of different color shades. Visual shade determination using a reference scale (3D-Master Toothguide (3DM_TG), VITA Zahnfabrik, Bad Säckingen, Germany), followed by a digital color determination using a spectrophotometer (VITA Easyshade V, (ES_V), VITA Zahnfabrik), was performed. Color deviation was calculated in the Lab* color space (ΔE00) and converted into CIELAB 2000. The results were evaluated using the Mann-Whitney U test and the Wilcoxon Rank Sum test (α = 0.05). Significant differences between visual and digital color determination were proven (p < 0.001). Visual color determination (3DM_TG) showed a mean deviation (ΔE00 ± 95%CI) of 6.49 ± 0.47. Digital color determination (ES_V) showed significantly lower mean deviations of ΔE00 of 1.44 ± 0.58. Digital tooth color measurement using a spectrophotometer was a more reliable tool for the color determination of 3D-printed teeth for inexperienced dentistry students.

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OBJECTIVES: Visual colour differentiation in clinical research requires colour-competent (CC) participants. The Ishihara colour charts (ICC) have established themselves as the standard for CC screening of colour vision deficiencies (CVD). However, the extent to which the results can be compared with a presentation of the colour charts on a smartphone display (SD) is currently unknown. The aim of this in vitro study was to determine the sensitivity and specificity of the Ishihara colour deficiency test depending on the presentation mode. METHODS: Dental students (female n = 28; male n = 10; mean age, 23.5 ± 2.65 years; median age, 23.0 ± 13.0 years) evaluated 25 Ishihara test plates on their SD (n = 38) and/or a calibrated monitor (HP monitor, 22-inch; n = 18). The median size of the SD was 6.0 inches. Datasets with more than 2 failed charts were scored. RESULTS: When the Ishihara test charts were presented on a PC screen, the sensitivity was 94.4% and the specificity was 82.4% (0 mistakes: n = 14, <3 failures: n = 3, 14 false answers: n = 1). On the SD, a sensitivity of 96.0% and a specificity of 94.7% were calculated (89.5% were correct; 4 participants [10.5%] made <3 errors; and 1 participant made 21 errors). No significant difference between display modi (PC vs SD) was evaluated (P > .05). CONCLUSIONS: The presentation of ICC on an SD is useful and can be used for the investigation of a possible CVD of large groups. Comparable results to data projection can be achieved with a high degree of certainty. For CVD screening of larger groups (eg, students in preclinical training as part of CC training), the presentation of ICC on the SD can be used. This research was able to demonstrate that the sensitivity and specificity of the usual presentation method (Ishihara's booklet or data projection) is comparable.

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Visual color determination (VCD) requires color competence and individual training. The aim of this study was to evaluate the deviations in students' VCD with two different reference scales. The research hypothesis was that none of the color references would provide a better result. Participants evaluated nine templates randomly using two reference scales (VITA-classical (VC) and 3D-Master-Toothguide (3DM_TG)). The color distance to the chosen color (ΔEab) was calculated in the CIELAB 2000. The sum's changes in the parameters (LCh°) represented the target variable. Results were evaluated with non-parametric, rank-scaled methods, utilizing the median with a 25%-75% quartile. The significance level (α = 0.05) is determined using the Student's t-test. The mean ± 95%CI (SD) was -1.27 ± -1.09 (3.18); the median ΔE00 was -1.49 (-1.97; 0.96) for dC3DM_TG. The determination with VC showed noticeable differences (dCVC), with a mean ΔE00 of 0.00 ± 0.00 (2.20) and a median ΔE00 of 0.00 (1.17; 1.71). The standard error was 0.19 for the dCVC and 0.27 for the dC3DM_TG. dC3DM_TG vs. dCVC showed significant differences at p < 0.001. The dental student's VCD resulted in color deviations, regardless of the reference template used. The color deviations in hue and chroma were comparable, regardless of the reference scale. VCD's early implementation in dental education is useful to avoid shade misjudgments and potentially expensive remakes of dentures.

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STATEMENT OF PROBLEM: Visual color determination in clinics or dental offices should take place under reproducible environmental conditions. To reduce false tooth color measurements, daylight and illumination lamps (5000-7500 K) have been recommended. Those can be used either as stationary or mobile handheld illumination units. However, depending on the manufacturer, the handheld lights use different illuminance brightness, and whether the choice of unit affects shade selection is unclear. PURPOSE: The purpose of this in vitro study was to determine whether the mobile handheld light-emitting diode (LED) lighting unit shows a significantly better result in visual color determination than the conventional reference lighting unit. MATERIAL AND METHODS: Trained preclinical dental students (N=23) with a mean ±standard deviation age of 24 ±5 years participated in the study. Two color differentiation lamps (Smile lite 1620lx and Dialite Color 4450lx) (SL and DC) were each placed at a 15-cm distance to determine the color of the shade tabs (templates, N=10) with the VITA Linear Guide 3D Master in a double-blinded study. According to the manufacturer's recommendation, polarization filters were used with the Smile lite lamp. RESULTS: Of N=220 shade determinations each, 31.8% (SL) and 33.2% (DC) were correct; the median (ΔE00) and interquartile range were 0.96 (±3.32) for SL and 1.35 (±3.28) for DC. The differences between the groups were not statistically significant (P=.67). CONCLUSIONS: The results show that the use of the mobile LED illumination unit did not improve color determination compared with the reference illumination. The different illumination intensities of 980 lux (SL) with a polarizing filter or 1500 lux (DC) did not have a positive effect.

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PURPOSE: To investigate whether viewing distance influences the results of visual tooth color differentiation. MATERIALS AND METHODS: A total of 65 students underwent both theoretical and practical training by a standardized lecture on the use of an internet learning module (Toothguide Trainer, VITA Zahnfabrik) and a standardized training program (Toothguide Training Box) for visual shade-taking. Each student matched 10 randomly selected shade tabs presented at different viewing distances (arm's length distance [AL, 70 cm] and AL/2 [35cm]) under lateral, non-glare lighting at a 45-degree angle with a color differentiation lamp. The results were recorded as to what extent the presented and selected tabs of the color determination matched. RESULTS: The overall median values of perceived color difference (ΔE) were 1.6 for AL/2 and 3.2 for AL, and these values were significantly different (P < .001). CONCLUSION: Within the limitations of this study, it was shown that the viewing distance had a significant influence on the color deviation in tooth color assessment. Therefore, a smaller viewing distance of 35 cm for shade determination is recommended.

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The paper structure of historical prints is sort of a unique fingerprint. Paper with the same origin shows similar chain line distances. As the manual measurement of chain line distances is time consuming, the automatic detection of chain lines is beneficial. We propose an end-to-end trainable deep learning method for segmentation and parameterization of chain lines in transmitted light images of German prints from the 16th Century. We trained a conditional generative adversarial network with a multitask loss for line segmentation and line parameterization. We formulated a fully differentiable pipeline for line coordinates' estimation that consists of line segmentation, horizontal line alignment, and 2D Fourier filtering of line segments, line region proposals, and differentiable line fitting. We created a dataset of high-resolution transmitted light images of historical prints with manual line coordinate annotations. Our method shows superior qualitative and quantitative chain line detection results with high accuracy and reliability on our historical dataset in comparison to competing methods. Further, we demonstrated that our method achieves a low error of less than 0.7 mm in comparison to manually measured chain line distances.

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OBJECTIVES: Visual shade selection is the most commonly used method in dentistry and a challenge for every dentist. However, differences to natural tooth color and the differences of each shade guide are well known. The aim of this paper is to investigate the suitability of two different color scales for determining the color of no-match templates. MATERIALS AND METHODS: Volunteers (N = 76) selected a shade color of a no-match template with two shade guides (VITA Classical shade guide (VC) and VITA Linearguide 3D-Master (V3D LG), both Vita Zahnfabrik). The neutral grey background was laterally illuminated with a color differentiation lamp (Dialite, Eickhorst GmbH). For the volunteers' accuracy, the triangle's area was used which are emerge by the color coordinates of a template (LT aT bT ) and the color coordinates of the two decisions (L1 a1 b1 and L2 a2 b2 ). Statistical software was used to evaluate the differences in ΔE00 with α = .01. RESULTS: A deviation in the median of ΔE00 of 7.6 (V3D LG, first choice) to 6.6 (VC, second choice) was detected, while U test showed no significant differences in the median for both color scales. But the triangle's area generated by both shade decisions and tooth color with V3D LG was significant smaller (14.2) then VC (19.2) (P ≤ .001). CONCLUSIONS: When comparing both results no significant difference in the subject's shade selection and the shade guides was detected. The new evaluation strategy using the size of the triangle's areas proves the superiority of the V3D LG due to a better distribution of the tooth color shades within the color space.

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OBJECTIVE: To compare the clinical performance of two glass-ionomer cements in combination with two light-cured coatings in Class II cavities. METHOD AND MATERIALS: In total, 43 Equia Fil/Equia Coat and 42 Fuji IX GP Fast/Fuji Coat LC restorations were placed, in 34 patients. Only Class II cavities with two- or three-surface restorations were included. The clinical performance was evaluated at baseline, after 1, 2, and 3 years using the FDI criteria. For the statistical analysis, Fisher exact test, Wilcoxon signed-rank test and Mann-Whitney U test were applied. The success and survival of the restorations were calculated with the Kaplan-Meier method and a log-rank test was used to detect significant differences between the tested materials. RESULTS: At the 3-year recall, no significant differences could be detected between the two glass-ionomer cements for any of the evaluated criteria (Mann-Whitney U test, P > .05). When comparing the baseline with the recall data at 3 years for each material separately, significant changes could be observed in both materials for the criteria "surface luster," "fracture of material and retention," and "approximal anatomical form" (Wilcoxon signed-rank test, P < .05). Additionally, the Equia Fil restorations showed a notable change for the criteria "marginal adaptation" (Wilcoxon signed-rank test, P = .039). At the 3-year follow up, the Equia Fil and the Fuji IX GP Fast restorations exhibited an overall survival rate of 89.3% and 88.0%, respectively. Three fillings in each group failed. CONCLUSION: The two glass-ionomer cements tested performed similarly in Class II cavities in adult patients, with a moderate failure rate after 3 years. (Original article published in Quintessence Int 2019;50:592-602; doi: 10.3290/j.qi.a42692).

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OBJECTIVE: To compare the clinical performance of two glass-ionomer cements in combination with two light-cured coatings in Class II cavities. METHOD AND MATERIALS: In total, 43 Equia Fil/Equia Coat and 42 Fuji IX GP Fast/Fuji Coat LC restorations were placed, in 34 patients. Only Class II cavities with two- or three-surface restorations were included. The clinical performance was evaluated at baseline, after 1, 2, and 3 years using the FDI criteria. For the statistical analysis, Fisher exact test, Wilcoxon signed-rank test and Mann-Whitney U test were applied. The success and survival of the restorations were calculated with the Kaplan-Meier method and a log-rank test was used to detect significant differences between the tested materials. RESULTS: At the 3-year recall, no significant differences could be detected between the two glass-ionomer cements for any of the evaluated criteria (Mann-Whitney U test, P > .05). When comparing the baseline with the recall data at 3 years for each material separately, significant changes could be observed in both materials for the criteria "surface luster," "fracture of material and retention," and "approximal anatomical form" (Wilcoxon signed-rank test, P < .05). Additionally, the Equia Fil restorations showed a notable change for the criteria "marginal adaptation" (Wilcoxon signed-rank test, P = .039). At the 3-year follow up, the Equia Fil and the Fuji IX GP Fast restorations exhibited an overall survival rate of 86.21% and 84.0%, respectively. CONCLUSION: The two glass-ionomer cements tested performed similarly in Class II cavities in adult patients, with a moderate to high failure rate after 3 years.

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OBJECTIVE: To develop and test self-administered satisfaction questionnaires for patients with removable dental prostheses (RDPs) in the German language. METHOD AND MATERIALS: A three-phase methodology was used. A pilot questionnaire was developed in phase one. At the end of phase two, the final version of the questionnaires were reached. In phase three, 192 questionnaires were distributed to evaluate the psychometric properties of the final version of the questionnaires. Construct validity, content validity from the patients' perspective, and questionnaire reliability were estimated. RESULTS: At the end of phase two, the final versions of the questionnaires were defined as instruments with good face validity. At the end of phase three, content validity from the patients' perspective was assessed and found to be good. Exploratory factor analysis identified a one-factor model for each questionnaire. Consequently, each questionnaire was summed to create a single index. Internal consistency of the indexes was assessed using Cronbach's α and found to be excellent (α > 0.9). A high repeatability of all the items was identified through a test-retest. Intra-class correlation coefficient (ICC) values ranged from 0.80 to 0.99. CONCLUSION: The questionnaires and indexes are valid and highly reliable instruments, and can be used to measure patient satisfaction with RDPs.

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STATEMENT OF PROBLEM: Dentists frequently use electronic devices to determine tooth color. However, neither the instructions for these devices nor the accompanying brochures refer to the environmental conditions required at the point of measurement. PURPOSE: The purpose of this multicenter prospective clinical study was to reveal whether a change in the oral background influences tooth color determination. MATERIAL AND METHODS: Students (N=42) at the dental clinic in Berlin, Leipzig, Greifswald and Olomouc (women n=27, men n=15) participated in this study. It was their first contact with the spectral photometer (Easyshade Advance 4.0; VITA Zahnfabrik). After a short introduction on how to use the device, the students made 1-point measurements on the same patient on the maxillary central incisor. In the first measurement, the patient's mouth was open, and the palatal surface uncovered. In the second measurement, the patient's mouth was closed slightly, and the tongue pressed on the lingual surface of the maxillary central incisor. The mean ±SD and the 95% confidence interval (95 % CI) were calculated using the Student t test for each test series (α=.05). RESULTS: Statistical evaluation of the 2 measurements revealed changes in the L*a*b* values with a mean L*=0.204, a*=-0.351, and b*=0.02; a median of 0.4, -0.3, and -0.1, respectively; a ±SD of 2.37, 0.64, and 0.89, respectively; and 95% CIs of L*=-0.476 to 0.884, a*=-0.531 to -0.702, and b*=-0.23 to 0.52, respectively. These differences were not statistically significant (P>.05). The measurements of L*, a*, and b* with and without tongue coverage of the lingual surfaces of the maxillary teeth did not show any statistically significant differences (P=.663). CONCLUSIONS: The results demonstrate that the position of the tongue does not influence measurement accuracy during the application of the Easyshade Advance device.

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BACKGROUND: This study was carried out as a prospective clinical field study with the aim of evaluating the clinical performance of Equia Fil® with a nanofilled resin coating and the conventional Fuji IX GP® fast with an LC coating according to the World Dental Federation (FDI) restoration material evaluation criteria. METHODS: The clinical performance of Equia Fil® and Fuji IX GP® fast was evaluated on permanent posterior teeth of 643 adult patients aged between 20 to 80 years old in randomly selected clinics across Germany. Occlusal cavities in posterior permanent teeth were restored with Equia Fil® with a nanofilled, light-cured resin coating (n = 515) and Fuji IX GP® fast with an LC coating (n = 486). Direct clinical assessment as well as photographic assessment and assessment of stone casts of the restorations were made at 1 year, 2 years, 3 years, and 4 years. RESULTS: In 4 years, a total of 1001 fillings from both materials were placed by 111 dentists in 643 patients. Random slope models showed that the Equia filling system had overall lower odds of obtaining a delta event (material needs replacement) in comparison to Fuji IX GP® fast with an LC coating within all models. In both materials, filling size/surface was the most important component affecting the clinical performance of the materials. When measuring the odds of obtaining a delta event (material needs replacement), the odds ratios jumped to approximately 43 and 296 times for class II (two surfaces) and class II mesial-occlusal-distal (three surfaces) respectively in comparison to class I fillings. CONCLUSION: Both materials showed similar good overall performance in class I cavities; however, when including numbers from both class I and II fillings, the Equia system with a nanofilled resin coating showed better overall performance with fewer failures in all the follow-up intervals. Nonetheless, the percentage of unsatisfactory to poor fillings according to the FDI criteria was relatively high in two-surface class II fillings and higher in three-surface class II fillings for both materials. TRIAL REGISTRATION: Deutsches Register Klinischer Studien (German Clinical Trials Register): DRKS00004220. ( www.germanctr.de ). Registration date: 6 Sept 2012.

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BACKGROUND: In 2009, we began recruiting dental practitioners across Germany to participate in a clinical trial to evaluate the clinical performance of EQUIA, a new glass ionomer restoration material. The aim of this paper is to discuss the outcomes of the dental practitioner recruitment and outline the process of establishing a practice-based research network. METHODS: Study proposals were sent to randomly selected dental offices in 29 cities in Germany. The proposals were sent until a minimum of 10 clinics in each city declared participation. Later on, briefing lectures informed the participating practitioners about the design, methods, and material application procedure. Participants were familiarized with the guidelines of Good Manufacturing Practice (GMP) and Good Epidemiological Practice (GEP). A questionnaire describing the characteristics of each dental office was filled out by the participating practitioner. Additionally, participation levels were characterized according to the socioeconomic status and geographic districts of residence in Germany (Regions 0 to 9). The associations between the characteristics were tested by the Kruskal-Wallis Test and Chi-squared test (P < 0.05). RESULTS: A total of 3194 private dental clinics were invited, 1712 clinics refused to participate, 1195 did not respond to the invitation, and 323 agreed to participate. Only 144 clinics participated in the lectures held in their cities and signed the participation agreement. Based on their geographic location, the highest participation was in Region 2 with a participation rate of 14.3%, and the lowest participation was in Region 6 with a participation rate of 1.7%. Regions with the lowest rate of unemployment and relatively higher rates of income (Regions 7 and 8) had the highest rate of refusals (86%). CONCLUSION: The initial results of the dental practitioner recruitment in this study suggest that the recruitment and pre-randomization design were successful, and by reaching out to a considerable number of private dental clinics to participate, we were able to recruit a smaller number of highly motivated dentists in this clinical study. Regional differences in socioeconomic status, practitioner specialization, and differences in patient health care insurance have to be considered when recruiting dental practitioners for clinical trials. TRIAL REGISTRATION: The trial has been registered at Deutsches Register Klinischer Studien (German register of clinical trials) on 6 September 2012 under DRKS-ID: DRKS00004220.

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OBJECTIVE: The purpose of this study was to determine the accuracy and reliability of Frankfort horizontal plane identification using displays of multi-planar reconstructed MRI images, and propose it as a sufficiently stable and standardized reference plane for craniofacial structures. MATERIALS AND METHODS: MRI images of 43 subjects were obtained from the longitudinal population based cohort study SHIP-2 using a T1-weighted 3D sequence. Five examiners independently identified the three landmarks that form FH plane. Intra-examiner reproducibility and inter-examiner reliability, correlation coefficients (ICC), coefficient of variability and Bland-Altman plots were obtained for all landmarks coordinates to assess reproducibility. Intra-examiner reproducibility and inter-examiner reliability in terms of location and plane angulation were also assessed. RESULTS: Intra- and inter-examiner reliabilities for X, Y and Z coordinates of all three landmarks were excellent with ICC values ranging from 0.914 to 0.998. Differences among examiners were more in X and Z than in Y dimensions. The Bland-Altman analysis demonstrated excellent intra- as well as inter-examiner agreement between examiners in all coordinates for all landmarks. Intra-examiner reproducibility and inter-examiner reliability of the three landmarks in terms of distance showed mean differences between 1.3 to 2.9 mm, Mean differences in plane angulation were between 1.0° to 1.5° among examiners. CONCLUSION: This study revealed excellent intra-examiner reproducibility and inter-examiner reliability of Frankfort Horizontal plane through 3D landmark identification in MRI. Sufficiently stable landmark-based reference plane could be used for different treatments and studies.

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BACKGROUND: Artifacts caused by dental restorations, such as dental crowns, dental fillings and orthodontic appliances, are a common problem in MRI and CT scans of the head and neck. The aim of this in-vitro study was to identify and evaluate the artifacts produced by different dental restoration materials in CT and MRI images. METHODS: Test samples of 44 materials (Metal and Non-Metal) commonly used in dental restorations were fabricated and embedded with reference specimens in gelatin moulds. MRI imaging of 1.5T and CT scan were performed on the samples and evaluated in two dimensions. Artifact size and distortions were measured using a digital image analysis software. RESULTS: In MRI, 13 out of 44 materials produced artifacts, while in CT 41 out of 44 materials showed artifacts. Artifacts produced in both MRI and CT images were categorized according to the size of the artifact. SIGNIFICANCE: Metal based restoration materials had strong influence on CT and less artifacts in MRI images. Rare earth elements such as Ytterbium trifluoride found in composites caused artifacts in both MRI and CT. Recognizing these findings would help dental materials manufacturers and developers to produce materials which can cause less artifacts in MRI and CT images.

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The aim of this study was to investigate the effects of BONITmatrix(®) and OSSA NOVA on the expression of growth factors and osteogenic differentiation. For this purpose, the mRNA expression of VEGF, IGF1, IGF2, collagen-1, collagen-2 and MMP8 was analysed in surgically created defects on the crania of adult male rats. Cranial samples were collected after implantation of BONITmatrix(®) or OSSA NOVA scaffolds for 4 weeks and determinations of gene expression were performed by quantitative RT-PCR. Real-time RT-PCR analyses showed a significantly higher expression of IGF1 in both groups treated with BONITmatrix(®) and OSSA NOVA compared to untreated controls, whereas type I collagen mRNA expression only increased in BONITmatrix(®) treated rats compared to controls. No changes in transcript expression of IGF2, VEGF, collagen-2 and MMP8 were detectable between the analysed groups. In conclusion, BONITmatrix(®) and OSSA NOVA stimulate the expression of growth factor IGF1, but only the granular dosage form is able to stimulate osteoblast differentiation.

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OBJECTIVES: To evaluate the influence of gender and level of experience on shade matching quality. METHODS: A study was simultaneously performed at 15 universities located in 9 countries. A total of 614 color normal participants completed all phases of the experiment. Among them, there were 305 females and 309 males, 319 dental students and 295 dental professionals. A lecture on color matching in dentistry was given to all participants. Initial training was performed using Toothguide Trainer software (TT), while Toothguide Training Box (TTB) was used for both training and testing of participants' shade matching results. The test task was to successively match 15 shade guide tabs with the corresponding shade guide. The shade matching score for each participant was computed as a sum of color differences (SigmaDeltaE(ab)(*) score) between target tabs and selected tabs. Lower scores corresponded to better shade matching results and vice versa. Means and standard deviations were calculated. Mann-Whitney U test was used for statistical analysis of the data (alpha=0.05). RESULTS: The mean shade matching score (S.D.) for all participants was 41 (21). The score for female and male participants was 38 (20) and 44 (21), respectfully (p<0.001). The difference in scores between dental students, 42 (20), and dental professionals, 39 (21), was not statistically significant. CONCLUSION: Within the limitations of this study, females achieved significantly better shade matching results than males, indicating that gender plays an important role in shade matching. The level of experience was not found to be significant factor in shade matching.

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Clinical methods of investigation, such as tooth colour determination, should be simple, quick and reproducible. The determination of tooth colours usually relies upon manual comparison of a patient's tooth colour with a colour ring. After some days, however, measurement results frequently lack unequivocal reproducibility. This study aimed to examine an electronic method for reliable colour measurement. The colours of the teeth 14 to 24 were determined by three different examiners in 10 subjects using the colour measuring device Shade Inspector. In total, 12 measurements per tooth were taken. Two measurement time points were scheduled to be taken, namely at study onset (T(1)) and after 6 months (T(2)). At either time point, two measurement series per subject were taken by the different examiners at 2-week intervals. The inter-examiner and intra-examiner agreement of the measurement results was assessed. The concordance for lightness and colour intensity (saturation) was represented by the intra-class correlation coefficient. The categorical variable colour shade (hue) was assessed using the kappa statistic. The study results show that tooth colour can be measured independently of the examiner. Good agreement was found between the examiners.

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The proteolytic potential of the pathogenic fungus Candida albicans was evaluated by the identification and functional characterization of a peptidolytic enzyme isolated from the cell wall of the microorganism. Determination of basic structural and kinetic data identified a neutral arginine/alanine/leucine-specific metallo-aminopeptidase of unknown function termed CaApe2, which is encoded by ORF CaO19.5197 (GenBank RefSeq XM_705313). Mass spectrometric tryptic peptide analysis and N-terminal protein sequencing revealed serine-88 to represent the N-terminus of CaApe2. Taking into account the results of DNA and protein sequence analysis including inspection of the genomic region upstream of ORF CaO19.5197, the gene CaAPE2 is likely to consist of two exons linked by a phase-2 intron with exons 1 and 2 encoding a signal peptide and the amino acids 88-954 of ORF CaO19.5197, respectively. The isolated CaApe2 protein shares an equally high similarity with the gene products ScAap1 and ScApe2, suggesting duplication of a phylogenetically ancient precursor gene in Saccharomyces cerevisiae. The observed failure to cleave human type-I and type-IV collagen in vitro challenges a direct role that secreted CaApe2 might play in the degradation of extracellular matrix components during host colonization, but does not exclude per se a contribution of the aminopeptidase to the pathogenicity of C. albicans.

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