Accuracy and reliability of 3D stereophotogrammetry: A comparison to direct anthropometry and 2D photogrammetry

Objective:To evaluate the accuracy of three-dimensional (3D) stereophotogrammetry by comparing it with the direct anthropometry and digital photogrammetry methods. The reliability of 3D stereophotogrammetry was also examined.Materials and Methods:Six profile and four frontal parameters were directly measured on the faces of 80 participants. The same measurements were repeated using two-dimensional (2D) photogrammetry and 3D stereophotogrammetry (3dMDflex System, 3dMD, Atlanta, Ga) to obtain images of the subjects. Another observer made the same measurements for images obtained with 3D stereophotogrammetry, and interobserver reproducibility was evaluated for 3D images. Both observers remeasured the 3D images 1 month later, and intraobserver reproducibility was evaluated. Statistical analysis was conducted using the paired samples t-test, intraclass correlation coefficient, and Bland-Altman limits of agreement.Results:The highest mean difference was 0.30 mm between direct measurement and photogrammetry, 0.21 mm between direct measurement and 3D stereophotogrammetry, and 0.5 mm between photogrammetry and 3D stereophotogrammetry. The lowest agreement value was 0.965 in the Sn-Pro parameter between the photogrammetry and 3D stereophotogrammetry methods. Agreement between the two observers varied from 0.90 (Ch-Ch) to 0.99 (Sn-Me) in linear measurements. For intraobserver agreement, the highest difference between means was 0.33 for observer 1 and 1.42 mm for observer 2.Conclusions:Measurements obtained using 3D stereophotogrammetry indicate that it may be an accurate and reliable imaging method for use in orthodontics.     

Comparison between direct clinical and digital photogrammetric measurements in patients with 22q11 microdeletion

Thanks to recent advances in imaging and computing technology, photoanthropometry has become an increasingly helpful adjunct to obtain objective clinical evidence of morphologic abnormalities in patients with dysmorphic syndromes. The aim of this study was to evaluate measurements made using a new two-dimensional digital photogrammetry technique by comparison with direct clinical measurements. A total of 14 patients with 22q11 microdeletion were included in this study. There were seven females and seven males between 5 and 38 years of age. Sixteen direct clinical measurements were performed using a graduated anthropometric sliding caliper and angle meter. Photogrammetric measurements were made on digital photographs using a commercially available software package. After calibration to one in situ reference on frontal and profile views, photogrammetric measurements were compared to a total of 14 direct clinical measurements made in the same patients. Findings showed that photogrammetric measurements calibrated to an in situ reference were reliable especially on profile views. No statistical difference was found between 10 of the 14 measurements (P> 0.05) including eight of the nine measurements on profile views and two of the five measurements on frontal views. This study indicates that digital photogrammetry is a useful tool but there is still no reliable standard photographic measurement technique.     

Validity of the combined use of two esthetic rating systems,the infant index and 5-point aesthetic index,for pre- and postsurgical evaluation of cleft lip repair

ObjectiveThe present study was designed to investigate the usefulness of combining two different ordinal scaling indices, infant index (I–I) and 5-point aesthetic index (5-PAI), for the assessment and prediction of esthetic outcome of primary lip repair for patients with unilateral cleft lip.Materials and methodsThe nasolabial appearance of the patients was evaluated before primary lip repair and at 5 years of age using cropped facial photographs with frontal and oblique views. The I–I and 5-PAI employ expanded reference photographs and objective esthetic variables for judgment.ResultsThe inter- and intrarater Kappa values of both I–I and 5-PAI demonstrated good to very good agreement (range: 0.74–0.84 for I–I and 0.62–0.77 for 5-PAI). Furthermore, both the declination of the columella and the deformity of the alar cartilage in I–I showed a correlation with nasal rating score of 5-PAI and were identified as predictable independent parameters (declination of the columella: Rs = 0.37, P = 0.04; deformity of the alar cartilage: Rs = 0.35, P = 0.02).ConclusionThe combined use of I–I and 5-PAI with expanded reference photographs and objective variables could be useful for obtaining greater accuracy of the esthetic assessment and predicting postsurgical nasolabial esthetics at infancy.     

New diagnostic tenet of the esthetic midface for clinical assessment of anterior malar projection

Objective:To determine whether a visual classification of anterior malar support using vector relationships is supported by cephalometric analysis.Materials and Methods:Forty white subjects between the ages of 10 and 12 years, without craniofacial syndromes or previous orthodontic treatment, were equally divided into groups based on visual assessment of negative and positive vector relationships. Group A comprised 20 subjects (10 male, 10 female) exhibiting a positive vector relationship. Group B comprised 20 subjects (10 male, 10 female) displaying a negative vector relationship. Sella-nasion-orbitale (SNO) angulations were measured to evaluate the subjects'' anteroposterior position of the malar eminence relative to the cranial base. Gender differences and significant differences in SNO measurements between groups A and B were assessed with Mann-Whitney U-tests.Results:There was no statistically significant difference between genders. SNO angulations in the negative vector group were smaller than the positive vector controls by an average of 6.0 degrees, and the difference was highly significant (P < .0001).Conclusion:Compared with subjects exhibiting a positive vector relationship, individuals displaying a negative vector relationship had significantly reduced malar support. Anterior malar projection can be effectively classified through visual assessment of vector relationships.     

Dimensional analyses of frontal posed smile attractiveness in Japanese female patients

Objective:To identify appropriate dimensional items in objective diagnostic analysis for attractiveness of frontal posed smile in Japanese female patients by comparing with the result of human judgments.Materials and Methods:Photographs of frontal posed smiles of 100 Japanese females after orthodontic treatment were evaluated by 20 dental students (10 males and 10 females) using a visual analogue scale (VAS). The photographs were ranked based on the VAS evaluations and the 25 photographs with the highest evaluations were selected as group A, and the 25 photos with the lowest evaluations were designated group B. Then 12 dimensional items of objective analysis selected from a literature review were measured. Means and standard deviations for measurements of the dimensional items were compared between the groups using the unpaired t-test with a significance level of P < .05.Results:Mean values were significantly smaller in group A than in group B for interlabial gap, intervermilion distance, maxillary gingival display, maximum incisor exposure, and lower lip to incisor (P < .05).Conclusions:Significant differences were observed only in the vertical dimension, not in the transverse dimension. Five of the 12 objective diagnostic items were correlated with human judgments of the attractiveness of frontal posed smile in Japanese females after orthodontic treatment.     

Interalar Distance to Estimate the Combined Width of the Six Maxillary Anterior Teeth in Oral Rehabilitation Treatment

Statement of the Problem:  The face's architecture of dentate subjects has been studied to find a reliable guide for the selection of artificial anterior teeth. However, there is no consensus of data regarding a reference to estimate the width of artificial teeth.
Purpose:  The purpose of this study was to analyze whether there is a consistent relationship between the interalar distance (IAD) and the combined mesiodistal width of the six maxillary anterior teeth.
Methods:  Standardized digital photographs of 81 dentate Brazilian subjects were included in the sample. They were 37 men and 44 women (age 17 to 33). Through image processing software, the IAD and the distance between the tips of the maxillary canines were measured when viewed from the frontal aspect. Accurate casts were made to quantify the distance between the distal surfaces of the maxillary canines on a curve, by use of a flexible millimeter ruler. Nonparametric statistics were performed to analyze the results ( p  < 0.05).
Results:  The IAD when compared with the width of the six maxillary anterior teeth, on a straight line and on a curve, presented a ratio of 0.914 and of 1.305, respectively. The Wilcoxon test showed no significant difference between the calculated width values and the mesiodistal width measured on a curve and on a straight line ( p  = 0.986).
Conclusion:  The IAD, when increased by 31% of its value, can suggest the circumferential distance of the six maxillary anterior teeth.

CLINICAL SIGNIFICANCE

The width of the nose, when measured in digital photographs, can be utilized as a reliable guide for the selection of the maxillary anterior teeth width. It can improve the esthetic result of the oral rehabilitation treatment for the edentulous patient by offering a natural dentofacial relation.     

Craniofacial anthropometry in a Turkish population.

OBJECTIVE: To present norms and demonstrate the anthropometric variations in fronto-occipital circumference, inner and outer canthal distances, near and distant [far] anatomical interpupillary distance, canthal index, and circumference-interorbital index across age and sex in urban Turkish subjects. PARTICIPANTS: Three thousand four hundred forty-eight subjects (1852 male, 1596 female) aged 7 to 40 years were included in this study. METHODS: Three age groups were studied: children aged 7 to 15 years, young adults aged 16 to 25 years, and adults aged 26 to 40 years. Mean values for each measured parameter were determined at each age between 7 and 25 years. Subjects were also divided into nine age subgroups to observe the change of each parameter with advancing age. RESULTS: The fronto-occipital circumference and outer canthal distance of males was significantly (p <.001) wider than females in all age groups. The near and distant interpupillary distances of male subjects were, on average, wider than the female subjects with greater differences with advancing age. Across all subjects aged 7 to 40 years, the mean of all measured parameters and calculated indexes of men and boys was significantly different from girls and women (p <.001). The mean for interpupillary distances in our study in both sexes were found to be similar to Arabian, Hong Kong, and British children; larger than those of Chinese, Black, Indian, and Caucasians; and smaller than those of Mexican children and a mixed European population. CONCLUSION: This study clearly shows the anthropometric variation for fronto-occipital circumference, inner canthal distance, outer canthal distance, near and distant interpupillary distance, canthal index, and circumference-interorbital index with age. These developmental data and the normal values of these measurements in healthy subjects are useful for dysmorphologists in the early identification of some craniofacial syndromes, hyper- and hypotelorism, and congenital or posttraumatic telecanthus and of planning surgical intervention. We suggest that the comparison of craniofacial dimensions of a patient must be performed with normal standards specific for age as well as sex and race.     

The perception of facial aesthetics in a young Spanish population

Improved facial aesthetics is one aim of orthodontic treatment. This study was designed to determine if the faces considered more beautiful in a young population exhibit the same parameters used by orthodontists to assess successful results. A panel of 34 laypeople (30 females and 4 males) evaluated a set containing one frontal, one frontal during smiling, and one profile photograph of 89 students (77 females and 12 males) on a 5-point attractiveness scale, in relation to a set of reference photographs. For each photographic set, the mean and final scores were calculated. Once the sample was established, 11 subjects (9 females and 2 males) with the highest final facial aesthetic score were selected and cephalometric analysis was performed. All cephalometric measurements were within the norm for the total sample. When the sample was divided by gender, Wilcoxon's W non-parametric test showed significant differences between the male and female photographs; while females tended to a Class II malocclusion, with the mandible slightly retrusive to the maxilla, males tended to a Class III and showed a straighter profile with a prominent chin; the face height ratio was higher in males. There were no significant differences between genders for lower lip to E plane. The findings show that the faces considered more attractive fulfilled the cephalometric and facial norms.     

Evaluation of facial attractiveness for patients with malocclusion: A machine-learning technique employing Procrustes

Objective:To establish an objective method for evaluating facial attractiveness from a set of orthodontic photographs.Materials and Methods:One hundred eight malocclusion patients randomly selected from six universities in China were randomly divided into nine groups, with each group containing an equal number of patients with Class I, II, and III malocclusions. Sixty-nine expert Chinese orthodontists ranked photographs of the patients (frontal, lateral, and frontal smiling photos) before and after orthodontic treatment from “most attractive” to “least attractive” in each group. A weighted mean ranking was then calculated for each patient, based on which a three-point scale was created. Procrustes superimposition was conducted on 101 landmarks identified on the photographs. A support vector regression (SVR) function was set up according to the coordinate values of identified landmarks of each photographic set and its corresponding grading. Its predictive ability was tested for each group in turn.Results:The average coincidence rate obtained for comparisons of the subjective ratings with the SVR evaluation was 71.8% according to 18 verification tests.Conclusions:Geometric morphometrics combined with SVR may be a prospective method for objective comprehensive evaluation of facial attractiveness in the near future.     

A comparison of methods for evaluating the marginal fracture of amalgam restorations

In this study, two methods for evaluating the marginal fracture of clinical amalgam restorations were compared. These were (1) matching photographs of the occlusal surfaces of restored teeth to a reference set of photographs; and (2) matching gypsum models of the same restored teeth to a reference set of gypsum models. Amalgam restorations made from 3 alloys were assessed at polish and at 1-, 2- and 3-year recalls. For each assessment period, both evaluation methods showed differences among the 3 alloys and ranked the alloys in the same order. Although the marginal fracture values for the photograph method were slightly higher than those for the model method, the correpondence between the values for each method was almost perfect (regression R²=0.988, α<0.001). Thus, in defining the 3-dimensional character of marginal fracture, the evaluation method using photographs was found to be equivalent to the evaluation method using models.     

The role of the divine proportion in the esthetic improvement of patients undergoing combined orthodontic/orthognathic surgical treatment

This study was designed to investigate the changes in a number of facial proportions as a result of combined orthodontic/orthognathic surgical treatment. According to some authors, in beautiful faces, the values of the proportions measured are likely to approximate the divine proportion (1.618:1). The hypothesis for this study was that, as a result of treatment, the faces of patients in the sample would be more esthetic and therefore the measured proportions would be closer to the divine proportion than they were before treatment. Forty-six patients were included in the sample. Pre- and posttreatment photographs were each given a score (out of a possible 100) by 12 judges using a visual analog scale. Judges were shown frontal and profile views simultaneously. Ten ratios were measured from pre- and posttreatment lateral cephalograms, and 11 were measured from the frontal photos. Pearson's correlation coefficient was used to determine the correlation between changes in esthetic rating and changes in the measured proportions. No correlations were found between changes in esthetic ratings and changes in the proportions. While most subjects were considered more esthetic after treatment than before, the proportions were equally likely to move away from or toward the divine proportion. For this reason, if it is to be used as an aid to orthodontic/orthognathic treatment planning, the divine proportion should perhaps be used along with other methods of anteroposterior and vertical cephalometric and facial assessment.     

Soft-tissue profile characteristics in children with beta thalassaemia major

Abstract

Objectives: To compare soft-tissue profile characteristics of patients with beta thalassaemia major (BTM) with a group of non-thalasseamic subjects with a similar skeletal pattern. Subjects and methods. The material for this cross-sectional retrospective study consisted of lateral cephalograms of 40 BTM patients (23 males, 17 females, aged 9.5 ± 0.97 years). These were compared with lateral cephalograms of a control group of 40 non-thalasseamic subjects (23 males, 17 females, aged 11.0 ± 0.87 years) who had similarities with the study group in the following cephalometric variables: SNA (°), SNB (°), ANB (°) and anterior face height (N-Me). Overall, 22 linear and angular soft-tissue cephalometric variables were measured. Results. Horizontal soft-tissue measurements, except for the thickness at B point (B-B'), were larger relative to non-thalasseamic subjects; particularly showing a statistically larger mean values for the following variables: soft-tissue thickness at Pronasale (ANS-Prn, p < 0.01), Subnasale (ANS-Sn, p < 0.01), point A (A-A′, p < 0.01) and at the Pogonion point (Pg-Pg′, p < 0.05). Compared to controls, BTM patients showed significantly larger (p < 0.05) mean values for the anterior nose length (Prn-Prn', p < 0.01) and lower nose height (Prn-Sn, p < 0.05). Variables that represented the lip profile, including the nasolabial angle, did not significantly differ from controls. The average values for the mid-face (N-ANS), posterior face height (S-Go) and the inclination of maxillary incisors to the SN plane were significantly larger (p < 0.01) in BTM patients. Conclusion: The soft-tissue profile differences in BTM patients may have implications for their future orthodontic or orthognathic management. Future studies can investigate the 3D soft-tissue changes and the possible contributing factors.     

Comparison of soft-tissue orbital morphometry in attractive and normal Italian subjects

Objective:To identify esthetic characteristics of the orbital soft tissues of attractive Italian adult women and men.Materials and Methods:Three-dimensional computerized digitizers were used to collect the coordinates of facial landmarks in 199 healthy, normal subjects aged 18 to 30 years (71 women, 128 men; mean age, 22 years) and in 126 coetaneous attractive subjects (92 women, 34 men; mean age, 20 years) selected during beauty competitions. From the landmarks, six linear distances, two ratios, six angles, and two areas were calculated. Attractive subjects were compared with normal ones by computing z-scores.Results:Intercanthal width was reduced while eye fissure lengths were increased in both genders. Orbital heights (os-or) were increased only in attractive women, with a significant gender-related difference. The inclinations of the eye fissure were increased in attractive subjects, while the inclinations of the orbit were reduced. For several of the analyzed measurements, similar patterns of z-scores were observed for attractive men and women (r  =  .883).Conclusion:Attractive women and men had several specific esthetic characteristics in their orbital soft tissues; esthetic reference values can be used to determine optimal goals in surgical treatment.     

Use of measuring gauges for in vivo accuracy analysis of intraoral scanners: a pilot study

PURPOSEThe purpose of this study is to present a methodology to evaluate the accuracy of intraoral scanners (IOS) used in vivo.MATERIALS AND METHODSA specific feature-based gauge was designed, manufactured, and measured in a coordinate measuring machine (CMM), obtaining reference distances and angles. Then, 10 scans were taken by an IOS with the gauge in the patient''s mouth and from the obtained stereolithography (STL) files, a total of 40 distances and 150 angles were measured and compared with the gauge''s reference values. In order to provide a comparison, there were defined distance and angle groups in accordance with the increasing scanning area: from a short span area to a complete-arch scanning extension. Data was analyzed using software for statistical analysis.RESULTSDeviations in measured distances showed that accuracy worsened as the scanning area increased: trueness varied from 0.018 ± 0.021 mm in a distance equivalent to the space spanning a four-unit bridge to 0.106 ± 0.08 mm in a space equivalent to a complete arch. Precision ranged from 0.015 ± 0.03 mm to 0.077 ± 0.073 mm in the same two areas. When analyzing angles, deviations did not show such a worsening pattern. In addition, deviations in angle measurement values were low and there were no calculated significant differences among angle groups.CONCLUSIONCurrently, there is no standardized procedure to assess the accuracy of IOS in vivo, and the results show that the proposed methodology can contribute to this purpose. The deviations measured in the study show a worsening accuracy when increasing the length of the scanning area.     

Photogrammetric evaluation of corrective surgery for trigonocephaly

The aim of this study was to capture preoperative, postoperative, and follow-up head shapes of male trigonocephaly patients who underwent fronto-orbital remodelling (FOR), using three-dimensional (3D) photography. Fifty-seven male infants with metopic synostosis operated on using standardized FOR during a 5-year period were included. All measurements were compared with those of an age-matched healthy control cohort (n = 253 for early postoperative comparison, n = 43 for the 1-year follow-up comparison) to determine the effect of FOR at 14 days and at 1 year post-surgery. Intracranial volume, frontal angle, nasofrontal angle, interfrontoparietal–interparietal ratio, and inter-orbital distances were measured 1 day preoperatively, 14 days and 1 year postoperatively. Mean age at surgery was 9.7 ± 1.1 months. Prior to surgery, boys with metopic synostosis showed a reduced intracranial volume (?7.0%, P < 0.001), frontal angle (?10.2%, P < 0.001), interfrontoparietal–interparietal ratio (?4.9%, P < 0.01), and orbital distances (?6.5%, P < 0.001) compared to the reference group, but values did not differ significantly from the specific control group after surgery (all P> 0.05). This was consistent by the time of the follow-up examination. Corrective surgery should therefore aim to achieve volume expansion and correction of the deformity. Furthermore, 3D photogrammetry provides a valuable alternative to computed tomography scans in the diagnosis of metopic synostosis, significantly reducing the amount of radiation exposure to the brain.     

Three-dimensional evaluation of facial asymmetry in association with unilateral functional crossbite in the primary,early, and late mixed dentition phases

Objective:To assess the degree of facial asymmetry associated with subjects with unilateral functional crossbite (CB) in the primary, early/intermediate, and late mixed dentition phases in comparison with a group of subjects without CB.Subjects and Methods:A group of 234 white subjects, 78 with CB (42 girls and 36 boys) and 156 without CB (73 girls and 83 boys), aged 3.9–11.9, grouped according to the dentition phase, were included. Three-dimensional laser scans of the subjects'' faces were used to assess facial asymmetry. For each part of the face two-way multivariate analysis of covariance was performed to assess differences among the subjects, and an independent sample t-test was used to assess the significance of the differences between data sets.Results:Within all dentition phases, the subjects with CB had statistically significantly greater facial asymmetry of the whole face than the subjects without CB, with the greatest values in the lower part of the face (P < .05). In the middle part of the face a significant difference was observed in the mixed dentition phases.Conclusions:Children with unilateral functional CB exhibited a greater facial asymmetry than children without this malocclusion in all the dentition phases herein investigated. The greatest differences were seen for the lower part of the face. Further, facial asymmetry in the middle part of the face became clinically relevant in combination with the transition from primary to mixed dentition phase.     

Differences in male and female dentists' practice patterns regarding diagnosis and treatment of dental caries: findings from The Dental Practice-Based Research Network

BackgroundA number of articles have addressed differences in productivity between male and female dentists, but little is known about differences between the sexes in practice patterns regarding caries management.MethodsIn this study, the authors surveyed general dentists who were members of The Dental Practice-Based Research Network (DPBRN) and who practiced within the United States. The survey included questions about dentists’, practices' and patients' characteristics, as well as prevention, assessment and treatment of dental caries. The authors adjusted the statistical models for differences in years since dental school graduation, practice model, full-time versus part-time status, and practice owner or employee status before making conclusions about sex differences.ResultsThree hundred ninety-three male (84 percent) and 73 female (16 percent) dentists participated. Female dentists recommended at-home fluoride to a significantly larger number of their patients than did male dentists, whereas male dentists had a preference for using in-office fluoride treatments with pediatric patients. Female dentists also chose to use preventive therapy more often at earlier stages of dental caries. There were few differences between the sexes in terms of diagnostic methods, time spent on or charges for restorative dentistry, and busyness of the practice.ConclusionsFemale DPBRN dentists differ from their male counterparts in some aspects of the prevention, assessment and treatment of dental caries, even with significant covariates taken into account.Practice ImplicationsThe practice patterns of female dentists suggest a treatment philosophy with a greater focus on caries prevention.     

Craniofacial growth in ectodermal dysplasia: an 8 year longitudinal evaluation of Italian subjects

Objective:To identify the main directions of growth of facial structures in subjects with hypohidrotic ectodermal dysplasia (HED).Materials and Methods:The 3D noninvasive facial measurements were collected in 12 subjects (6 boys, 6 girls) with HED during four assessments (at 8, 11, 12, and 15 years) using an electromagnetic digitizer. The modifications of linear distances in the upper, middle, and lower third of the face were analyzed and compared with cross-sectional data obtained in normal healthy coetaneous. For each distance, differential values between the last and the initial data were calculated individually, separately for a first (8–11 years) and a second growth period (12–15 years).Results:In the first time span, the growth of all facial measurements was reduced in HED subjects compared with control subjects. During this interval, most of the HED children underwent a functional and/or prosthetic treatment. During adolescence, the width and height of the lower and upper facial thirds showed a larger growth in HED subjects than in control subjects, while all facial depths and all distances in the middle facial third maintained a reduced growth.Conclusions:The deviation from normal facial growth of HED subjects tends to lessen with age. Functional and prosthetic appliances may have enhanced facial growth.     

Influence of facial type on attractiveness of vertical canine position from the perspective of orthodontists and laypeople

ObjectivesTo evaluate the attractiveness of changes in vertical position of maxillary canines in frontal smiles of different facial types, and to evaluate the esthetic perceptions of orthodontists and laypeople, and the influence of facial type on these perceptions.Materials and MethodsThree adult female volunteers were selected as individuals with normal, vertical, and horizontal growth patterns. Frontal posed smile photographs were digitally altered by adjusting vertical positions of the maxillary canines above, below, or coincident with the incisal line in increments of 0.5 mm within a range of 1 mm of extrusion and intrusion. For assessment, a web-based survey was formed with 18 images (six images for each model). A scale was present underneath each image, graded from 0 to 10 (0: unattractive; 10: the most attractive). Images were rated by 233 participants (105 orthodontists; 128 laypeople).ResultsOrthodontists scored 0-mm images significantly as the highest in all groups. Laypeople scored significantly higher for −0.5 mm images regardless of facial type. The lowest scored images were −1 mm (except for horizontal pattern) and +1 mm images. Mean values of scores given by men were higher (P < .05).ConclusionsOrthodontists favored ideal dental alignment and preferred the incisal edges of central and canine teeth to be at the same level. Laypeople preferred a smoother smile arc than orthodontists and found harmony with the soft tissue more attractive. Facial type affected perceptions of the vertical changes of maxillary canines.     

Measurement accuracy of marginal bone level in digital radiographs with and without color coding

Objective. New radiographic techniques have made it possible to color-code intra-oral digital radiographs. The purpose of the present study was to compare the accuracy and precision of marginal bone level measurements in digital radiographs with and without color coding. Material and methods. Periapical digital radiographs of 21 patients were processed with and without a color-coding algorithm. The patients had periodontal surgery immediately after exposure of radiographs, and vertical distances from the cemento-enamel junction (CEJ) to the most apical part of the marginal bone were measured clinically. The measured values were considered as a reference standard and subtracted from the corresponding radiographic vertical distance. Seven observers contributed to the radiographic measurements under the same viewing conditions. Results. No statistically significant differences were found between absolute differences of vertical distances obtained from radiographs and their corresponding reference standards in the two types of radiograph. Intra- and inter-observer variability was not significant. Conclusion. Color-coded digital radiographs did not provide a more favorable accuracy when assessing marginal alveolar bone levels than black-and-white radiographs and thus did not improve measurement of such levels.