Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 17 de 17
Filter
1.
J Oral Rehabil ; 51(4): 712-723, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38087990

ABSTRACT

BACKGROUND: Tooth wear is a multifactorial condition that manifests through various signs and symptoms. These individual signs and symptoms were described in multiple studies, leading to the inclusion in TWES 2.0 (Tooth Wear Evaluation System 2.0) and the forthcoming DC-TW (Diagnostic Criteria for Tooth Wear). However, a study evaluating their reliability has yet to be conducted. OBJECTIVE: The aim of the study was to examine the reliability in the assessment of 6 signs of pathological tooth wear and 18 clinical signs and symptoms determining aetiology, all of which are included in the TWES 2.0/DC-TW. METHODS: 48 dental students (operators) evaluated patient cases from a patient pool of 14 patients on dental casts and high-resolution intraoral photographs. The agreement between all operators for each sign and symptom was calculated based on ICC (Intraclass Correlation Coefficients). Additionally, the agreement of each operator's evaluation with a predefined sample solution was calculated based on Cohen's kappa. RESULTS: Inter-user agreement ranged from near perfect (0.91) to poor (0.02) for the various pathology signs or aetiology symptoms of tooth wear (mean 0.32). The agreements of the operator's ratings compared to the sample solution resulted in Cohen's kappa from 0.18 to 1 (mean 0.59) for the pathology signs and ranged from 0.02 to 0.51 for the aetiology signs (mean 0.38). CONCLUSIONS: The reliability of the signs and symptoms examined and the ability of individual investigators to correctly identify and assign signs and symptoms varied widely. The current assessment tools for the qualification of tooth wear need further refinement, and examiners need intensive training in tooth wear assessment.


Subject(s)
Molar , Tooth Wear , Humans , Reproducibility of Results , Tooth Wear/diagnosis
2.
J Oral Rehabil ; 49(1): 81-91, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34719055

ABSTRACT

BACKGROUND: Tooth wear is a multifactorial process, leading to the loss of dental hard tissues. Therefore, it is important to detect the level of tooth wear at an early stage, so monitoring can be initiated. The Tooth Wear Evaluation System (TWES) enables such a multistage diagnosis of tooth wear. The further developed TWES 2.0 contains a complete taxonomy of tooth wear, but its reliability has not yet been validated. OBJECTIVES: The aim of the study was to examine in a randomised controlled trial (RCT) whether diagnoses made based on the TWES 2.0 are reproducible and whether this reproducibility is also achieved with computer-assisted diagnostics. METHODS: 44 dental students received extensive training in TWES 2.0 assessment and taxonomy. The students each evaluated at least 10 (of the present 14) anonymised patient cases using gypsum models and high-resolution intra-oral photographs according to TWES 2.0. One half initially evaluated on paper; the other half used dedicated software (CMDfact / CMDbrux). After half of the patient cases (5), the evaluation methods were switched (AB/BA crossover design). The diagnoses were then evaluated for agreement with the predefined sample solution. RESULTS: Evaluation of agreement with the sample solution according to Cohen's kappa indicated a value of 0.46 for manual (traditional) evaluation; and 0.44 for computer-assisted evaluation. Evaluation of agreement between examiners was 0.38 for manual and 0.48 for computer-assisted evaluation (Fleiss' kappa). CONCLUSION: The results of this study proved that the taxonomy of the TWES 2.0 has acceptable reliability and can thus be used by dentists. Accordingly, the system can be learned quickly even by untrained practitioners. Comparable results are achieved with computer-assisted evaluation.


Subject(s)
Tooth Attrition , Tooth Erosion , Tooth Wear , Computers , Cross-Over Studies , Humans , Reproducibility of Results , Tooth Erosion/diagnosis , Tooth Wear/diagnosis
3.
Clin Oral Investig ; 23(3): 1007-1014, 2019 Mar.
Article in English | MEDLINE | ID: mdl-29926254

ABSTRACT

OBJECTIVES: The benefit from positioning the maxillary casts with the aid of face-bows has been questioned in the past. Therefore, the aim of this study was to investigate the reliability and validity of arbitrary face-bow transfers compared to a process solely based on the orientation by means of average values. For optimized validity, the study was conducted using a controlled, randomized, anonymized, and blinded patient simulator study design. MATERIAL AND METHODS: Thirty-eight undergraduate dental students were randomly divided into two groups; both groups were applied to both methods, in opposite sequences. Investigated methods were the transfer of casts using an arbitrary face-bow in comparison to the transfer using average values based on Bonwill's triangle and the Balkwill angle. The "patient" used in this study was a patient simulator. All casts were transferred to the same individual articulator, and all the transferred casts were made using type IV special hard stone plaster; for the attachment into the articulator, type II plaster was used. A blinded evaluation was performed based on three-dimensional measurements of three reference points. RESULTS: The results are presented three-dimensionally in scatterplots. Statistical analysis indicated a significantly smaller variance (Student's t test, p < 0.05) for the transfer using a face-bow, applicable for all three reference points. CONCLUSIONS: The use of an arbitrary face-bow significantly improves the transfer reliability and hence the validity. CLINICAL RELEVANCE: To simulate the patient situation in an individual articulator correctly, casts should be transferred at least by means of an arbitrary face-bow.


Subject(s)
Dental Articulators , Models, Dental , Humans , Jaw Relation Record , Maxilla , Reproducibility of Results
4.
Int J Comput Dent ; 21(4): 281-294, 2018.
Article in English | MEDLINE | ID: mdl-30539170

ABSTRACT

Functional diagnostic examinations such as clinical functional analysis and manual structural analysis ('orthopedic tests') allow the dentist to establish a structured diagnosis. Previously, the process of correlating findings with the appropriate diagnoses was guided by human thought processes alone. The experimental diagnostic randomized controlled trial (RCT) in this study investigated whether computer-aided diagnosis (CADx) of temporomandibular disorders (TMD) offers quality advantages over traditional diagnosis (TRAD). SUBJECTS AND METHODS: Thirty-nine 5th-year dental students (examiners) at a university in Hamburg, Germany, received joint training in the diagnosis of TMD by clinical functional analysis and manual structural analysis ('orthopedic tests'). This study is based on anonymized data from 10 patients who were consecutively recruited at a specialized TMJ treatment center. The examiners were randomly allocated to two groups. Each examiner established a structured diagnosis through a traditional diagnostic method and by computer-aided diagnosis (CMDfact 4 functional diagnostics software) of five cases, each using the AB/BA crossover design. The diagnoses established by each individual examiner were then compared with the corresponding reference diagnoses (gold standard) and with those of the other examiners. RESULTS: Cohen's kappa coefficient analysis showed that median agreement with the reference diagnoses was significantly higher (P < 0.001) with computer assistance (median 0.692) than without it (0.553). Fleiss' kappa showed that the median interexaminer consistency of diagnoses was significantly higher (P < 0.001) with computer assistance (0.497) than with traditional diagnostic methods alone (0.271). Likewise, the number of false-positive and false-negative diagnoses was significantly lower with computer assistance (P < 0.001). CONCLUSIONS: This study determined that dentists who are less experienced and not specialized in dental functional diagnostics achieve a significantly better and more consistent diagnostic quality with computer assistance by means of the system used in this study. Therefore, it seems advisable to extend computer-aided diagnostics to further functional examination techniques (condylar position analysis and jaw motion analysis).


Subject(s)
Diagnosis, Computer-Assisted , Temporomandibular Joint Disorders/diagnosis , Cross-Over Studies , Education, Dental , Humans , Quality Improvement , Students, Dental
5.
J Prosthet Dent ; 117(2): 289-293, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27646799

ABSTRACT

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.


Subject(s)
Tongue/anatomy & histology , Tooth/anatomy & histology , Color , Esthetics, Dental , Female , Humans , Incisor/anatomy & histology , Male , Prospective Studies , Spectrophotometry
6.
J Esthet Restor Dent ; 28(5): 277-286, 2016 09.
Article in English | MEDLINE | ID: mdl-27534729

ABSTRACT

OBJECTIVES: The objective of this prospective learning research study is to examine the impact of structured elaborative feedback in practical skills teaching of visual and digital shade matching. MATERIALS AND METHODS: A total of 60 preclinical dental students participated in the study. The mean average age was 23 years, of which 37 were female (61.7%) and 23 male (38.3%). The participants were randomly divided into a study and control group (n = 30 each). Recording of shade matching was carried out on the phantom patient using clinically simulated settings with elaborative feedback in the study group (T1). Nine items were recorded for visual shade matching and six items for digital shade-taking. The errors were coded. The lower the total (max. 30 points), the fewer the errors made by students during shade determination. The subject labeled the tooth color using VITA 3D-Master and VITA Easyshade (Vita Zahnfabrik, Bad Säckingen, Germany). RESULTS: On comparing the two groups, the study group and the control group showed a similar mean error value at reference time T1. After intervention (T2) it was possible to achieve a clear improvement in the rate of errors for study group. In the study group there was a significant difference between the ΔE values from time T1 and T2 of visual shade matching (p <0.05). The digital ΔE values show in total no significant changes. CONCLUSION: Elaborative feedback in conjunction with standardized checklists can lead to a substantial improvement among students in terms of visual shade matching. CLINICAL SIGNIFICANCE: Correctly determining the tooth shade is an essential treatment step in esthetic reconstructive dentistry. Color is probably one of the most important determinants of esthetics in dentistry. Factors such as lighting conditions, gender, age, experience, and color vision impairment affect the process of shade matching. With an elaborative feedback in conjunction with standardized checklists can lead to a substantial improvement among students in terms of visual shade matching. (J Esthet Restor Dent 28:277-286, 2016).


Subject(s)
Color Perception , Dental Prosthesis Design , Feedback , Prosthesis Coloring , Students, Dental , Color , Education, Dental , Female , Humans , Male , Prospective Studies
7.
Int J Comput Dent ; 18(3): 201-23, 2015.
Article in English, German | MEDLINE | ID: mdl-26389133

ABSTRACT

Mandibular movement recording has long been established as the method for the physiological design of indirect dental restorations. Condylar movement recording is the basis for individual, patient-specific programming of partially or fully adjustable articulators. The settings derived from these recordings can generally be used in both traditional mechanical and electronic virtual articulators. For many years, condylar movement recordings have also provided useful information about morphological conditions in the temporomandibular joints (TMJs) of patients with masticatory system dysfunction based on the recorded movement patterns. The latest clinical application for recorded jaw-motion analysis data consists of functional monitoring of the patient as a diagnostic and surveillance tool accompanying treatment. Published parameters for the analysis of such recordings already exist, but a standardized and practicable protocol for the documentation and analysis of such jaw-movement recordings is still lacking. The aim of this article by a multicenter consortium of authors is to provide an appropriate protocol with the documentation criteria needed to meet the requirements for standardized analysis of computer-assisted recording of condylar movements in the future.


Subject(s)
Dental Occlusion , Jaw Relation Record/instrumentation , Mandible/physiology , Mandibular Condyle/physiology , Range of Motion, Articular/physiology , Software , Calibration , Computer-Aided Design , Dental Articulators , Equipment Design , Humans , Movement , Temporomandibular Joint/physiology , Temporomandibular Joint Disorders/diagnosis , User-Computer Interface
8.
Quintessence Int ; 0(0): 0, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38934773

ABSTRACT

OBJECTIVES: To evaluate the survival rate of minimally invasive semipermanent occlusal polymethylmethacrylate (PMMA) onlays/veneers in previous temporomandibular disorder (TMD) patients with severe tooth wear and with a loss of vertical dimension after up to 7 years. METHOD AND MATERIALS: This case series was designed as a follow-up evaluation with consecutive patient recruitment. All patients bearing the indication for this kind of rehabilitation were treated by the same clinician using the same adhesive methodology. The study included 22 patients (3 males/19 females), with a mean [SD] age of 50.7 [11.6] years. Controls followed within the first 4 weeks (and subsequently as required). Failure criteria included damage by fracture, chipping, and retention loss. Survival rates were determined based on the Kaplan-Meier analysis. RESULTS: 328 semipermanent occlusal/incisal veneers were included (142 maxillary/186 mandibular teeth). Almost 80% of the restorations were in place and in function when starting the follow-up treatment after 180 days; failures predominantly occurred within the first 3 to 6 months but proved reparable. Depending on the patients' priorities, scheduled replacements followed successively, and more than 65% did not show repair or any renewal needs for more than 360 days. CONCLUSION: Within the limitations of this study the survival rates of occlusal veneers made of PMMA were sufficiently high to allow for consecutive treatment of the respective teeth by means of permanent restorations while preserving the restored vertical dimension. In patients with severe tooth wear and a TMD history, semipermanent restorative therapy with occlusal PMMA onlays/veneers would seem a noteworthy option.

9.
Dent J (Basel) ; 12(2)2024 Jan 26.
Article in English | MEDLINE | ID: mdl-38392228

ABSTRACT

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.

10.
Sci Rep ; 13(1): 11721, 2023 07 20.
Article in English | MEDLINE | ID: mdl-37474563

ABSTRACT

The present study investigated to what extent a systematic evaluation of electronic condylar motion recordings leads to reproducible results in different examiners. The study was based on the anonymized condylar motion recordings of 20 patients (Cadiax compact II system). These were recruited consecutively from the examinations in a center specializing in diagnosing and managing temporomandibular disorders (TMD). Four trained practitioners independently evaluated the identical movement recordings of all patients after calibration. The evaluation was based on the previously published evaluation system. The results were recorded digitally in a database. The findings were then compared, and the matching values were determined (Fleiss' Kappa). The evaluation, according to Fleiss' Kappa, showed that the consistency of the assessment of the findings among the examiners is excellent (mean value 0.88, p < 0.00001). The study shows that calibrated dentists achieved reproducible results using this evaluation system and computer-assisted reporting. Good reproducibility confirms the reliability of systematic evaluation of clinical motion analysis. The ambiguities uncovered and eliminated in the study should avoid misunderstandings in the future. Both factors establish the prerequisites for applying condylar motion analysis in clinical practice.


Subject(s)
Mandibular Condyle , Temporomandibular Joint Disorders , Humans , Reproducibility of Results , Temporomandibular Joint Disorders/diagnosis , Movement , Computers , Temporomandibular Joint
11.
J Prosthodont Res ; 2023 Oct 17.
Article in English | MEDLINE | ID: mdl-37853627

ABSTRACT

PURPOSE: To investigate whether depth-gauge burs in veneer preparations influence preparation depth in a randomized, controlled, single-blinded trial and whether inexperienced operators can perform adequate veneer preparations. METHODS: Participants were 20 undergraduate dental students with no prior veneer preparation experience. The instruments used were the "Laminate Veneer System" (LVS), "Keramik-Veneers. de" (KVD), and a "Freehand" group (FH) for reference. All participants prepared three educational acrylic resin maxillae and three mandibular central incisors mounted in typodonts in patient simulators. The objectives were to achieve a preparation depth of 0.6 mm (tooth 11) and 0.4 mm (tooth 31). The sequences of the instruments used and prepared teeth were randomized. The measurements were performed using a laser triangulation coordinate-measuring machine. The data were stratified according to tooth location. RESULTS: The preparation depths of both depth-gauge-instrument-groups LVS and KVD achieved the objectives significantly better than did the instruments from the "Freehand" group (P < 0.001). The differences between the depth gauge groups were insignificant, although the maximum preparation depths were smaller in the KVD group. Regarding the prepared teeth, the preparation depths in the mandibular incisors were lower, and the differences were smaller. CONCLUSIONS: The use of special depth-gauge burs for initial veneer preparation leads to significantly lower preparation depths than "Freehand" preparations. The tapered instruments resulted in a lower incidence of extreme preparation depths. The inexperienced operators performed veneer preparation remarkably well.

12.
Dent J (Basel) ; 11(12)2023 Nov 29.
Article in English | MEDLINE | ID: mdl-38132413

ABSTRACT

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.

13.
GMS J Med Educ ; 33(1): Doc2, 2016.
Article in English | MEDLINE | ID: mdl-26958650

ABSTRACT

OBJECTIVE: Tooth shade differentiation concerns the identification and classification of tooth shades. The objective of this project was to implement the Clinical Tooth Shade Differentiation Course in the preclinical stage of studies and to evaluate the students' perspective over a period of 3 years. METHODOLOGY: The course is planned for a duration of 10 weeks with two 45-minute sessions per semester week. The entire attendance time was 10:15 h. 2 lectures of 90 minutes each, 2 seminars of 60 min each and 2 teaching units with the phantom head and role playing took place. In addition to the various parameters of tooth shade, changes in tooth shade and the basics of dental esthetics, clinical procedures for manual and digital tooth shade determination were explained and practiced. 96% (69 of 72) of the students participated in the first evaluation in 2012/2013 (T1), and 68% of these were women. In the following year, 2013/2014 (T2), 92% (45 of 48 students) took part; 62% of these were women and 38% men. The 2014/2015 evaluation (T3) comprised 94% (45 of 48 students). Of these, 67% were women. RESULTS: In the evaluation, the students gave the course a positive grade. The questions in "General/Organization" were given a mean (M) of 1.5 (SD=0.7) in T1 and T2, and 1.2 (SD=0.3) in T3. The "Overall Assessment" yielded M(T1)=1.6 (SD=0.6), M(T2)=1.5 (SD=0.5) and M(T3)=1.1 (SD=0.3). In T1 and T2, the item "The instructor actively involved the students in the course" was given a mean of 2.1 (SD=0.9), and in T3 a mean of 1.2 (SD=0.5). CONCLUSIONS: The course presented here conceptually shows how practical dental skills can be taught in a theoretical and clinical context. Educational objectives from the role of a dental expert were taken from the national competence-based catalog of educational objectives for dentistry and can also be supplemented. The objectives can be transferred to other dental faculties.


Subject(s)
Color Perception , Curriculum , Discrimination Learning , Education, Dental , Esthetics, Dental , Tooth , Adult , Attitude of Health Personnel , Clinical Competence , Female , Humans , Male , Students, Dental/psychology
14.
Work ; 48(1): 27-35, 2014.
Article in English | MEDLINE | ID: mdl-23531582

ABSTRACT

BACKGROUND: Playing a wind instrument can be either a reason for overuse or a protecting factor against certain diseases. Some individuals have many findings but low morbidity while others have few findings but high morbidity. This contradictory phenomenon should be researched. OBJECTIVE: The temporomandibular system (TMS) is a functional unit which comprises the mandible, associated muscles and bilateral joints with the temporal bone. The TMS is responsible for the generation of sound when wind instruments are played. Over the long-term and with intensive usage, this causes changes in the musculature and in the temporomandibular joint (TMJ) of wind musicians, often resulting in temporomandibular disorders (TMD). The aim of this study is to examine evidence that TMD constitute an occupational disease in wind musicians. PARTICIPANTS: TMD patients and wind musicians were examined by dental clinical functional analysis. 102 male subjects were divided into three groups: "healthy" individuals, wind musicians, and patients with TMD. METHODS: Dental Examination was carried out based on focused inclusion of the research diagnostic criteria - TMD [1,7]. Findings were evaluated for statistical significance by first transferring data into a digital database [2,15], then generating T-Test und Wilcoxon-Test when non-Gaussian distribution appears and applying the Mann-Whitney rank sum test using Sigmaplot Version 1.1 software (Systat Software Inc, Washington, USA). RESULTS: The evaluation revealed that wind instrument musicians show a high incidence of developing TMD as the researchers found almost 100% morbidity regarding parafunctional habits and preauricular muscle pain of each adult and highly active musician. The result is highly significant (p< 0.001) for protrusion distance of the mandible. CONCLUSIONS: A higher prevalence of functional disorders of the musculoskeletal system has previously been demonstrated in wind musicians. New research results and the typical functions of various wind instruments provide evidence that playing a wind instrument generates occupational risks to the TMS.


Subject(s)
Music , Occupational Diseases/etiology , Sound/adverse effects , Temporomandibular Joint Disorders/etiology , Temporomandibular Joint/physiopathology , Adult , Cross-Sectional Studies , Germany , Humans , Male , Masseter Muscle/physiopathology , Middle Aged , Occupational Diseases/epidemiology , Occupational Diseases/physiopathology , Prevalence , Risk Assessment , Statistics, Nonparametric , Temporomandibular Joint Disorders/epidemiology , Temporomandibular Joint Disorders/physiopathology
15.
Eur J Esthet Dent ; 6(1): 94-102, 2011.
Article in English | MEDLINE | ID: mdl-21403930

ABSTRACT

PURPOSE: To determine the color space and the coverage error of two manual shade guide systems in four age groups of a selected population. MATERIAL AND METHODS: A total of 174 patients were divided into four age groups and the shade of their natural teeth was measured (2067 teeth) with a spectrophotometer (Vita Easyshade). Color parameters in terms of L*, a*, b* values, chroma, and hue were recorded for each tooth. Color difference (ΔE*min) between each natural tooth and the closest match using two manual shade guide systems were calculated (3D Master shade guide standard and 3D Master shade guide with intermediate values). A Wilcoxon test was used to assess statistical differences between mean ΔE*min values for each system (α = 0.05). RESULTS: The recoded ΔE of the two tested manual systems was 6.19 for 3D Master shade guide (standard) and 6.02 for 3D Master shade guide (intermediate values). A statistically significant difference (P < 0.001) was found between the mean ΔE*min of the two systems. 47% of natural teeth presented a best match with intermediate value and chroma shade tabs. The mean ΔE*min was influenced by the age group of the patients (5.15, 5.23, 6.58, and 6.69, respectively). CONCLUSION: Using intermediate value and chroma did not improve shade match, nor the coverage error of the tested population. Nevertheless, better coverage error was observed in younger age groups compared to older anterior teeth.


Subject(s)
Dental Prosthesis Design/instrumentation , Prosthesis Coloring/instrumentation , Tooth/anatomy & histology , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Algorithms , Color , Dental Prosthesis Design/standards , Female , Humans , Image Processing, Computer-Assisted , Imaging, Three-Dimensional , Male , Middle Aged , Prosthesis Coloring/standards , Spectrophotometry , Young Adult
16.
J Dent ; 38 Suppl 2: e41-9, 2010.
Article in English | MEDLINE | ID: mdl-20659524

ABSTRACT

OBJECTIVES: The aim of this study was to evaluate whether simulated severe red and green color vision deficiency (CVD) influenced color matching results and to investigate whether training with Toothguide Trainer (TT) computer program enabled better color matching results. METHODS: A total of 31 color normal dental students participated in the study. Every participant had to pass the Ishihara Test. Participants with a red/green color vision deficiency were excluded. A lecture on tooth color matching was given, and individual training with TT was performed. To measure the individual tooth color matching results in normal and color deficient display modes, the TT final exam was displayed on a calibrated monitor that served as a hardware-based method of simulating protanopy and deuteranopy. Data from the TT final exams were collected in normal and in severe red and green CVD-simulating monitor display modes. Color difference values for each participant in each display mode were computed (∑ΔE(ab)(*)), and the respective means and standard deviations were calculated. The Student's t-test was used in statistical evaluation. RESULTS: Participants made larger ΔE(ab)(*) errors in severe color vision deficient display modes than in the normal monitor mode. TT tests showed significant (p<0.05) difference in the tooth color matching results of severe green color vision deficiency simulation mode compared to normal vision mode. Students' shade matching results were significantly better after training (p=0.009). CONCLUSIONS: Computer-simulated severe color vision deficiency mode resulted in significantly worse color matching quality compared to normal color vision mode. Toothguide Trainer computer program improved color matching results.


Subject(s)
Color Vision Defects , Dental Prosthesis Design/instrumentation , Diagnosis, Computer-Assisted/instrumentation , Prosthesis Coloring/standards , Tooth Discoloration/diagnosis , Adult , Color/standards , Computer Simulation , Computer-Assisted Instruction , Discrimination Learning , Female , Humans , Male , Reference Values , Students, Dental , Tooth Discoloration/classification , Young Adult
17.
J Dent ; 37 Suppl 1: e40-4, 2009.
Article in English | MEDLINE | ID: mdl-19520478

ABSTRACT

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.


Subject(s)
Clinical Competence/statistics & numerical data , Color/standards , Dental Prosthesis Design/statistics & numerical data , Dentists, Women/statistics & numerical data , Dentists/statistics & numerical data , Prosthesis Coloring/statistics & numerical data , Adolescent , Adult , Color Perception , Dental Prosthesis Design/standards , Dental Restoration, Permanent/methods , Dental Restoration, Permanent/statistics & numerical data , Discrimination, Psychological , Esthetics, Dental , Female , Humans , Male , Middle Aged , Observer Variation , Prosthesis Coloring/standards , Sex Factors , Students, Dental/statistics & numerical data , Young Adult
SELECTION OF CITATIONS
SEARCH DETAIL