Cephalometric evaluation of deep overbite correction using anterior bite turbos.

OBJECTIVES: To evaluate the outcome of treating deep overbite (OB) using anterior bite elevators concurrently with a pre-adjusted edgewise appliance. MATERIALS AND METHODS: The Case Western Reserve University (CWRU) cephalometric analysis was used to isolate tipping movement of upper (TUI) and lower incisors (TLI), bodily tooth movement of upper (BUI), and lower incisors (BLI), as well as vertical skeletal changes in the anterior region of the maxilla (MXSK) and mandible (MNSK). Thirty treated subjects were examined at pretreatment (T1) and posttreatment (T2) and compared to an untreated control group matched on age, sex, and Angle malocclusion from the Bolton Brush Growth Study Collection (CWRU, Cleveland, Ohio). RESULTS: Overbite (OB) in the treated group was decreased significantly (P < .001) (-5.6 mm) compared to controls. Statistically significant (P < .001) changes were found for BUI (-0.7 mm), TUI (0.9 mm), TLI (-1.4 mm), BLI (-1.1 mm), and MNSK (-1.6 mm). Most of the overbite correction was in the lower arch and included tipping and intrusion of the lower incisors along with an increase in lower vertical facial height. CONCLUSIONS: Deep OB correction was achieved efficiently using anterior bite elevators with pre-adjusted edgewise appliance. Correction using bite turbos would be a treatment option for individuals presenting with decreased lower facial height and deep bite.

Sleep disordered breathing in children seeking orthodontic care.

INTRODUCTION: Our objective was to evaluate the prevalence of high-risk factors for sleep disordered breathing (SDB) in an orthodontic population of children. SDB is a spectrum of breathing disorders ranging from primary snoring to obstructive sleep apnea. METHODS: The sample included 303 healthy children between the ages of 9 and 17. High risk of SDB was assessed using the Pediatric Sleep Questionnaire, a validated instrument that consists of 22 questions, and high risk is defined as positive answers to 33% or more of the questions answered. Sixteen randomly selected patients repeated the questionnaire 1 month after the initial survey for reliability. RESULTS: In this sample, high-risk status on the Pediatric Sleep Questionnaire was not associated with sex, age, or race. The percentage of patients who were screened as high risk was 7.3% (95% confidence interval, 4.7%-10.6%). CONCLUSIONS: The results of this study suggest that approximately 7% of adolescent orthodontic patients may be at a significant risk for some form of SDB.

Radiocarbon chronology of Manot Cave, Israel and Upper Paleolithic dispersals.

The timing of archeological industries in the Levant is central for understanding the spread of modern humans with Upper Paleolithic traditions. We report a high-resolution radiocarbon chronology for Early Upper Paleolithic industries (Early Ahmarian and Levantine Aurignacian) from the newly excavated site of Manot Cave, Israel. The dates confirm that the Early Ahmarian industry was present by 46,000 calibrated years before the present (cal BP), and the Levantine Aurignacian occurred at least between 38,000 and 34,000 cal BP. This timing is consistent with proposed migrations or technological diffusions between the Near East and Europe. Specifically, the Ahmarian could have led to the development of the Protoaurignacian in Europe, and the Aurignacian in Europe could have spread back to the Near East as the Levantine Aurignacian.

Effects of Case Western Reserve University's transverse analysis on the quality of orthodontic treatment.

INTRODUCTION: The purpose of this study was to evaluate the effect of using the transverse analysis developed at Case Western Reserve University (CWRU) in Cleveland, Ohio. The hypotheses were based on the following: (1) Does following CWRU's transverse analysis improve the orthodontic results? (2) Does following CWRU's transverse analysis minimize the active treatment duration? METHODS: A retrospective cohort research study was conducted on a randomly selected sample of 100 subjects. The sample had CWRU's analysis performed retrospectively, and the sample was divided according to whether the subjects followed what CWRU's transverse analysis would have suggested. The American Board of Orthodontics discrepancy index was used to assess the pretreatment records, and quality of the result was evaluated using the American Board of Orthodontics cast/radiograph evaluation. The Mann-Whitney test was used for the comparison. RESULTS: CWRU's transverse analysis significantly improved the total cast/radiograph evaluation scores (P = 0.041), especially the buccolingual inclination component (P = 0.001). However, it did not significantly affect treatment duration (P = 0.106). CONCLUSIONS: CWRU's transverse analysis significantly improves the orthodontic results but does not have significant effects on treatment duration.

Gingival crevicular fluid bone turnover biomarkers: How postmenopausal women respond to orthodontic activation.

INTRODUCTION: Bone turnover associated with orthodontic tooth movement is evidenced by increased bone turnover markers in gingival crevicular fluid (GCF). Postmenopausal women have an increased concentration of serum bone turnover markers. The filtrate of this serum makes up GCF, but little is known of the bone turnover around teeth in this cohort. The objective of this investigation was to compare the GCF bone turnover markers in premenopausal vs postmenopausal women receiving orthodontic treatment at baseline and at orthodontic activation. METHODS: Twenty-eight women were enrolled in the study and separated into 2 groups: premenopausal (16) and postmenopausal (12). Bone turnover was evaluated by GCF at baseline and 24 hours after orthodontic appliance activation. GCF concentrations of RANKL and OPN were measured using ELISA. Baseline and change in concentrations were compared between groups. RESULTS: Baseline RANKL and OPN were significantly different between the premenopausal and postmenopausal groups (P <0.05). Both markers increased significantly from baseline to 24 hours after orthodontic appliance activation in both groups (P <0.05). However, the response to orthodontic activation was not significantly different between groups. CONCLUSIONS: Although postmenopausal women have a different bone turnover profile at baseline than do their premenopausal counterparts, there is no difference in their response to orthodontic activation. This confers a level of security associated with orthodontic activation. Future studies are warranted to construct biomarker curves throughout orthodontic therapy.

When static meets dynamic: Comparing cone-beam computed tomography and acoustic reflection for upper airway analysis.

INTRODUCTION: Upper airway measurement can be important for the diagnosis of breathing disorders. Acoustic reflection (AR) is an accepted tool for studying the airway. Our objective was to investigate the differences between cone-beam computed tomography (CBCT) and AR in calculating airway volumes and areas. METHODS: Subjects with prescribed CBCT images as part of their records were also asked to have AR performed. A total of 59 subjects (mean age, 15 ± 3.8 years) had their upper airway (5 areas) measured from CBCT images, acoustic rhinometry, and acoustic pharyngometry. Volumes and minimal cross-sectional areas were extracted and compared with software. RESULTS: Intraclass correlation on 20 randomly selected subjects, remeasured 2 weeks apart, showed high reliability (r >0.77). Means of total nasal volume were significantly different between the 2 methods (P = 0.035), but anterior nasal volume and minimal cross-sectional area showed no differences (P = 0.532 and P = 0.066, respectively). Pharyngeal volume showed significant differences (P = 0.01) with high correlation (r = 0.755), whereas pharyngeal minimal cross-sectional area showed no differences (P = 0.109). The pharyngeal volume difference may not be considered clinically significant, since it is 758 mm3 for measurements showing means of 11,000 ± 4000 mm3. CONCLUSIONS: CBCT is an accurate method for measuring anterior nasal volume, nasal minimal cross-sectional area, pharyngeal volume, and pharyngeal minimal cross-sectional area.

History of imaging in orthodontics from Broadbent to cone-beam computed tomography.

The history of imaging and orthodontics is a story of technology informing biology. Advances in imaging changed our thinking as our understanding of craniofacial growth and the impact of orthodontic treatment deepened. This article traces the history of imaging in orthodontics from the invention of the cephalometer by B. Holly Broadbent in 1930 to the introduction of low-cost, low-radiation-dose cone-beam computed tomography imaging in 2015.

Levantine cranium from Manot Cave (Israel) foreshadows the first European modern humans.

A key event in human evolution is the expansion of modern humans of African origin across Eurasia between 60 and 40 thousand years (kyr) before present (bp), replacing all other forms of hominins. Owing to the scarcity of human fossils from this period, these ancestors of all present-day non-African modern populations remain largely enigmatic. Here we describe a partial calvaria, recently discovered at Manot Cave (Western Galilee, Israel) and dated to 54.7 ± 5.5 kyr bp (arithmetic mean ± 2 standard deviations) by uranium-thorium dating, that sheds light on this crucial event. The overall shape and discrete morphological features of the Manot 1 calvaria demonstrate that this partial skull is unequivocally modern. It is similar in shape to recent African skulls as well as to European skulls from the Upper Palaeolithic period, but different from most other early anatomically modern humans in the Levant. This suggests that the Manot people could be closely related to the first modern humans who later successfully colonized Europe. Thus, the anatomical features used to support the 'assimilation model' in Europe might not have been inherited from European Neanderthals, but rather from earlier Levantine populations. Moreover, at present, Manot 1 is the only modern human specimen to provide evidence that during the Middle to Upper Palaeolithic interface, both modern humans and Neanderthals contemporaneously inhabited the southern Levant, close in time to the likely interbreeding event with Neanderthals.

An interview with Mark G. Hans.

It is a great honor to conduct an interview with Professor Mark G. Hans, after following his outstanding work ahead of the Bolton-Brush Growth Study Center and the Department of Orthodontics at the prestigious Case Western Reserve School of Dental Medicine (CWRU) in Cleveland, Ohio. Born in Berea, Ohio, Professor Mark Hans attended Yale University in New Haven, CT, and earned his Bachelor of Science Degree in Chemistry. Upon graduation, Dr. Hans received his DDS and Masters Degree of Science in Dentistry with specialty certification in Orthodontics at Case Western Reserve University. During his education, Dr. Hans' Master's Thesis won the Harry Sicher Award for Best Research by an Orthodontic Student and being granted a Presidential Teaching Fellowship. As one of the youngest doctors ever certified by the American Board of Orthodontics, Dr. Hans continues to maintain his board certification. He has worked through academics on a variety of research interests, that includes the demographics of orthodontic practice, digital radiographic data, dental and craniofacial genetics, as obstructive sleep apnea syndrome, with selected publications in these fields. One of his noteworthy contributions to the orthodontic literature came along with Dr. Donald Enlow on the pages of "Essentials of Facial Growth", being reference on the study of craniofacial growth and development. Dr. Mark Hans's academic career is linked to CWRU, recognized as the renowned birthplace of research on craniofacial growth and development, where the classic Bolton-Brush Growth Study was historically set. Today, Dr. Hans is the Director of The Bolton-Brush Growth Study Center, performing, with great skill and dedication, the handling of the larger longitudinal sample of bone growth study. He is Associate Dean for Graduate Studies, Professor and Chairman of the Department of Orthodontics, working in clinical and theoretical activities with students of the Undergraduate Course from the School of Dental Medicine and residents in the Department of Orthodontics at CWRU. Part of his clinical practice at the university is devoted to the treatment of craniofacial anomalies and to special needs patients. Prof. Mark Hans has been wisely conducting the Joint Cephalometric Experts Group (JCEG) since 2008, held at the School of Dental Medicine (CWRU). He coordinates a team composed of American, Asian, Brazilian and European researchers and clinicians, working on the transition from 2D cephalometrics to 3D cone beam imaging as well as 3D models for diagnosis, treatment planning and assessment of orthodontic outcomes. Dr. Hans travels to different countries to give lectures on his fields of interest. Besides, he still maintains a clinical orthodontic practice at his private office. In every respect, Dr. Hans coordinates all activities with particular skill and performance. Married to Susan, they have two sons Thomas and Jack, and one daughter Sarah, and he enjoys playing jazz guitar for family and friends.

Use of intraoral miniplates to control postoperative occlusion after high condylectomy for the treatment of condylar hyperplasia.

Mandibular condylar hyperplasia is a rare disorder, characterized by unilateral mandibular overgrowth with overeruption of the dentition on the affected side. Although the etiology is unclear, multiple surgical techniques have been described to correct the associated mandibular bone, occlusal, and soft tissue deformities. Often a condylectomy, to arrest mandibular growth, is combined with various orthognathic procedures to restore occlusion and facial harmony. Here we report our technique of isolated high condylectomy with simultaneous intraoral placement of maxillary and mandibular miniplates. Each plate has an intraoral extension that allows our orthodontists to develop vertical force vectors to intrude the maxillary and mandibular molar segments. Using this combined surgical and orthodontic technique, we were able to postoperatively control the occlusal cant, restore the dental midline, improve facial aesthetics, and resolve the patient's contralateral temporomandibular joint dysfunction without concomitant orthognathic surgery. As a result of our findings, we are currently using, and would recommend, this technique for patients requiring surgical-orthodontic intervention for other conditions.

Linear and angular measurements from plain film cephalometry, 3DCeph, and CBCT / Medidas angulares e lineares em cefalometria em telerradiografias de norma lateral, cefalometria tridimensional, e em tomografias de feixe em cone

The advent of cone beam computed tomography (CBCT) in orthodontics raises the question of how it compares with existing diagnostic tools in providing useful quantitative measures. This study compared linear and angular measurements from craniometry (Cranio), plain film cephalometry (Ceph), three-dimensional cephalometry (3DCeph), and CBCT. Methods: Sixteen linear and fourteen angular measurements were taken using Cranio, Ceph, 3DCeph, and CBCT in 6”, 9”, and 12” field of views (FOV) from five dry skulls. Cranio values defined the “gold standard” for linear measurements, and Ceph values the angular. Paired t-tests and correlations were used for comparison. Results: For linear measurements, Ceph had the most significant differences, followed by 3DCeph and CBCT. All had high (r>0.75) correlations. Average discrepancies were 4.18 mm for Ceph, 1.32 mm for 3DCeph, and less than 1 mm for CBCT in all three FOVs. For angular measurements, CBCT(9) and CBCT(6) were not considered due to incompleteness. Cranio had 6 significant differences, CBCT had 5, and 3DCeph had 2. Cranio and CBCT had low correlations for FMA and FMIA. Average discrepancies were 2.7O for Cranio, 2.1O for CBCT, and 1.8O for 3DCeph. Conclusions: CBCT compared favorably with craniometry for linear measurements, but not with traditional cephalometrics for angular.

A incorporação da tomografia de feixe em cone (TFC) na ortodontia estimula a pergunta de como esta modalidade se compara com as modalidades já em uso. Este estudo compara medidas lineares e angulares para os métodos de craniometria (Crânio), cefalometria em teleradiografias (Ceph), cefalometria tridimensional (3DCeph), e de tomografia de feixe em cone (TFC). Métodos: 16 medidas lineares e 14 angulares foram feitas usando os métodos Crânio, Ceph, 3DCeph, e TFC nos tamanhos de imagem 15, 23, e 38 cm feitas de 5 crânios secos. O valores do método Crânio representam o padrão-ouro para as medidas lineares, e o método Ceph para as medidas angulares. O teste-t dependente e correlações foram usados para esta comparação. Resultados: Para as medidas lineares, o método Ceph mostrou-se com maiores diferenças, seguido pelos métodos 3DCeph e TFC. Todos os métodos mostraram altas correlações (r>0.75). As discrepâncias médias foram 4,18 mm para o método Ceph, 1,32para o 3DCeph, e menos de 1mm para o método TFC, para todos os tamanhos de imagem. Nas medidas angulares, os tamanhos 15cm e 23 cm não puderam ser incluidos por não poder-se realizar todas as medidas desejadas, sendo que alguns pontos cefalométricos não estavam presentes na imagem. O método Crânio teve 6 medidas significamente diferentes, TFC teve 5, e 3DCeph teve 2. Crânio e TFC tiveram baixa correlação para as medias FMA e FMIA. A discrepância média foi de 2.7O para o método Crânio, 2.1O para o TFC, e para o 3DCeph. Conclusões: O método TFC se compara favoralmente com a craniometria para medidas lineares, mas não tanto com a cefalometria para medidas angulares.

Retainer wear and compliance in the first 2 years after active orthodontic treatment.

INTRODUCTION: The purpose of this descriptive study was to estimate retainer wear and compliance among orthodontic patients in the first 2 years after active orthodontic treatment. METHODS: A random sample of 1200 orthodontic patients was selected from 4 offices. Data were collected by a self-administered questionnaire that consisted of 6 items: type of retainer prescribed, age, sex, length of time since debond, and hours per day and nights per week that patients wore their retainers. Responses were solicited by mail or the Internet. Data were gathered on a categorical scale and analyzed. RESULTS: The overall response rate was 36% during a 6-week period. In the first 3 months after debond, 60% of patients were wearing their retainers more than 10 hours during a 24-hour cycle, and 69% were wearing the retainers every night. At 19 to 24 months after debond, 19% of the patients were not wearing their retainers, and 81% wore their retainers at least 1 night per week. Compliance rates during the periods of 0 to 3, 4 to 6, 7 to 9, 10 to 12, 13 to 18, and 19 to 24 months were 69%, 76%, 55%, 62%, 45%, and 45%, respectively. Age, sex, and type of retainer did not influence the levels of compliance. CONCLUSIONS: Most continued to wear their retainers at least 1 night per week, with compliance rates, as defined, tending to decrease in our sample. It was encouraging that 81% of the patients in this sample largely maintained their orthodontic result.

Effects of extraction versus non-extraction treatment on oropharyngeal airway volume.

OBJECTIVE: To compare the effects of extraction vs nonextraction orthodontic treatments on oropharyngeal airway volume. MATERIALS AND METHODS: An existing patient database was screened for pretreatment (T0) and posttreatment (T1) cone beam computed tomography (CBCT) scans and complete medical histories. Twenty patients treated with removal of four premolars (ExtG) and 20 controls (NExtG), were matched for age, gender, ethnicity, height, weight, body mass index, and oropharyngeal (OP) volumes, among other variables. Constructed lateral cephalograms (three skeletal and four dental variables) and OP volumes were measured at T0 and T1 using Dolphin Imaging 11.0. Independent sample t-tests were used to compare the groups at T0 and the outcome variables at T1. Paired sample t-tests were used to compare the mean changes from T0 to T1. Statistical significance was set at P < or = .05. RESULTS: Changes from T0 to T1 were found to be significant in both groups for CoA, CoGn, U1-FH, and IMPA. In the ExtG alone, U1-Na Perp and L1-Na Perp were also significantly different from T0 to T1. Despite the observed differences, no significant differences were found at the end of treatment between the mean OP volumes for either group (12,675.6 +/- 4483.6 for ExtG; 12,002.7 +/- 2857.0 for NExtG, P > .05). Similarly, the mean changes in OP volume (1082.6 mm(3) and 1701.1 mm(3) for ExtG and NExtG, respectively) and increase in mean minimal constricted axial areas (17.4 mm(2) and 1.9 mm(2) for ExtG and NExtG, respectively, P > .05) from T0 to T1 were not significant for the two groups. CONCLUSION: Extraction of four premolars with retraction of incisors does not affect OP airway volume.

Accuracy and reliability of cone-beam computed tomography for measuring alveolar bone height and detecting bony dehiscences and fenestrations.

INTRODUCTION: The purpose of this study was to evaluate the accuracy and reliability of cone-beam computed tomography (CBCT) in the diagnosis of naturally occurring fenestrations and bony dehiscences. In addition, we evaluated the accuracy and reliability of CBCT for measuring alveolar bone margins. METHODS: Thirteen dry human skulls with 334 teeth were scanned with CBCT technology. Measurements were made on each tooth in the volume-rendering mode from the cusp or incisal tip to the cementoenamel junction and from the cusp or incisal tip to the bone margin along the long axis of the tooth. The accuracy of the CBCT measurements was determined by comparing the means, mean differences, absolute mean differences, and Pearson correlation coefficients with those of direct measurements. Accuracy for detection of defects was determined by using sensitivity and specificity. Positive and negative predictive values were also calculated. RESULTS: The CBCT measurements showed mean deviations of 0.1 +/- 0.5 mm for measurements to the cementoenamel junction and 0.2 +/- 1.0 mm to the bone margin. The absolute values of the mean differences were 0.4 +/- 0.3 mm for the cementoenamel junction and 0.6 +/- 0.8 mm for the bone margin. The sensitivity and specificity of CBCT for fenestrations were both about 0.80, whereas the specificity for dehiscences was higher (0.95) and the sensitivity lower (0.40). The negative predictive values were high (>or=0.95), and the positive predictive values were low (dehiscence, 0.50; fenestration, 0.25). The reliability of all measurements was high (r >or=0.94). CONCLUSIONS: By using a voxel size of 0.38 mm at 2 mA, CBCT alveolar bone height can be measured to an accuracy of about 0.6 mm, and root fenestrations can be identified with greater accuracy than dehiscences.

Pretreatment characteristics associated with orthodontic treatment duration.

INTRODUCTION: Pretreatment characteristics can assist orthodontists in accurately estimating treatment duration. METHODS: This case-control study identified 400 patients, 9 to 18 years of age. Short treatment duration was 20 months or less, and long treatment duration was 30 months or longer. Potential pretreatment explanatory variables included planned treatment, sociodemographic, behavior, dental, skeletal, and soft-tissue characteristics. Univariable and multivariable logistic regression modeling was used to quantify the association between patient characteristics and treatment duration by reporting the unadjusted odds ratios (ORcrude), the adjusted odds ratios (ORadj), and the 95% confidence intervals (CIs). RESULTS: Patients planned as nonextraction (ORadj = 2.3; 95% CI, 1.3-4.2), no deciduous teeth (ORadj = 3.0; 95% CI, 1.5-5.9), less than 80% overbite (ORadj = 2.4; 95% CI, 1.3-4.4), less than 6 mm of maxillary crowding (ORadj = 3.6; 95% CI, 1.7-7.7), and good oral hygiene (ORadj = 3.2; 95% CI, 1.3-1.8) were 2 to 3 times more likely to have short treatments. Patients with decreased lower facial height (ORadj = 3.4; 95% CI, 1.6-7.1), extractions (ORadj = 1.8; 95% CI, 1.0-3.2), deciduous teeth (ORadj = 1.9; 95% CI, 1.0-3.4), poor grades (ORadj = 2.0; 95% CI, 1.1-3.8), excessive overjet (ORadj = 2.3; 95% CI, 1.4-3.8), 80% or more overbite (ORadj = 2.0; 95% CI,1.2-3.6), and 6 mm or more of maxillary crowding (ORadj = 2.6; 95% CI,1.4-4.6) were 2 to 3 times more likely to have long treatments. CONCLUSIONS: Presence or absence of severe maxillary crowding, deciduous teeth, 80% overbite, and extractions were consistently, inversely, and independently associated with short and long treatment durations.

Dental practice network of U.S. dental schools.

As dental schools incorporate training in evidence-based dentistry (EBD) into their curricula, students must learn how to critically evaluate systematic reviews and meta-analyses. It is important that dental education in the United States support the American Dental Association's position statement on EBD, which defines "best evidence" as data obtained from all study designs. Given that much evidence is missing when EBD is derived from Cochrane Systematic Reviews' randomized clinical trials, we propose the creation of a dental practice network of U.S. dental schools. We developed an electronic clinical dentistry research database for EBD using Epi-Info (available at www.cdc.gov/epiinfo/downloads.htm). As a free, public use software, Epi-Info provides the foundation for the development of clinical research databases that can increase the research capacity through multisite studies designed to generate outcomes data on the effectiveness of dental treatment. The creation of a dental practice network of dental schools with their large number of patients would expand the research capacity for EBD practice and advance the EBD science regarding the effectiveness of dental treatment. The next step is to link clinical dental researchers/educators at multiple dental schools through a collaborative clinical research network, so that the findings can be applied to the EBD component of problem-based learning curricula of dental education.

Buccal cortical bone thickness for mini-implant placement.

INTRODUCTION: The thickness of cortical bone is an important factor in mini-implant stability. In this study, we investigated the buccal cortical bone thickness of every interdental area as an aid in planning mini-implant placement. METHODS: From the cone-beam computed tomography scans of 30 dry skulls, 2-dimensional slices through every interdental area were generated. On these, cortical bone thickness was measured at 2, 4, and 6 mm from the alveolar crest. Intraclass correlation was used to determine intrarater reliability, and analysis of variance (ANOVA) was used to test for differences in cortical bone thickness. RESULTS: Buccal cortical bone thickness was greater in the mandible than in the maxilla. Whereas this thickness increased with increasing distance from the alveolar crest in the mandible and in the maxillary anterior sextant, it behaved differently in the maxillary buccal sextants; it was thinnest at the 4-mm level. CONCLUSIONS: Interdental buccal cortical bone thickness varies in the jaws. There appears to be a distinct pattern. Knowledge of this pattern and the mean values for thickness can aid in mini-implant site selection and preparation.

Reliability and accuracy of cone-beam computed tomography dental measurements.

INTRODUCTION: Dental measurements are an integral part of the orthodontic records necessary for proper diagnosis and treatment planning. In this study, we investigated the reliability and accuracy of dental measurements made on cone-beam computed tomography (CBCT) reconstructions. METHODS: Thirty human skulls were scanned with dental CBCT, and 3-dimensional reconstructions of the dentitions were generated. Ten measurements (overbite, overjet, maxillary and mandibular intermolar and intercanine widths, arch length available, and arch length required) were made directly on the dentitions of the skulls with a high-precision digital caliper and on the digital reconstructions with commercially available software. Reliability and accuracy were assessed by using intraclass correlation and paired Student t tests. A P value of < or = 0.05 was used to assign statistical significance. RESULTS: Both the CBCT and the caliper measurements were highly reliable (r >0.90). The CBCT measurements tended to slightly underestimate the anatomic truth. This was statistically significant only for compounded measurements. CONCLUSIONS: Dental measurements from CBCT volumes can be used for quantitative analysis. With the CBCT images, we found a small systematic error, which became statistically significant only when combining several measurements. An adjustment for this error allows for improved accuracy.