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This study aimed to identify a simple yet reliable soft-tissue parameter for the clinical determination of esthetic lip position by investigating the most consistent reference lines and assessing their sensitivity and specificity. A total of 5745 records from Chinese patients aged >18 years were screened. In part I of the study, lateral view photographs of 96 subjects (33 males, 63 females) with esthetic facial profiles were selected. The profile esthetics of each photograph was first scored by 52 dental students, followed by 97 laypeople on a 5-point attractiveness scale. For the top 25% of photographs with the highest score for each sex (8 males, 16 females), the consistency of 6 commonly used reference lines were assessed to determine the esthetic lip position. In part II of the study, lip positions relative to Steiner's (S) and Ricketts' (E) lines in the profile photographs of 86 patients (43 males, 43 females) deemed to have an esthetically unpleasing profile were compared with those in 86 Chinese movie star idols (43 males, 43 females). In part I of the study, the S, E, and Burstone's (B) lines exhibited the lowest standard deviations for the upper and lower lips. B line was excluded from further analysis because of its higher mean absolute values, and S and E lines were used for the subjective assessment in part II of the study. In part II, the S line showed a sensitivity of 86.0% and 86.0% and a specificity of 81.4% and 83.7% for males and females, respectively. In contrast, the E line presented a sensitivity of 88.4% and 93.0% and a specificity of 79.1% and 74.4% for males and females, respectively. S, E, and B lines were the most consistent soft-tissue parameters among both sexes; however, because of the smaller absolute values, the S line would be more convenient among the 3 for a quick clinical assessment of lip position. Moreover, the performance of both S and E lines was similar among both sexes, which supports using these lines in assessing the esthetic lip position. • The presented methodology applies to patients from various ethnic backgrounds. • The methodology has potential applications in photogrammetry analysis. • The S, E, and B lines are the most consistent soft-tissue parameters for lip position assessment. • The S line would be more convenient for the quick assessment of lip position clinically. [ABSTRACT FROM AUTHOR]

This study assessed whether preoperative class III patients could recreate their facial difference based on a profile photograph. Twenty class III pre-surgery bimaxillary orthognathic patients used CASSOS (SoftEnable Technology Ltd.) to manipulate a distorted soft tissue image of them until they felt it resembled their current soft tissue profile. Patients were able to move their upper lip and lower chin backward and forwards, as well as the lower chin up and down. Differences in the mean absolute distance between the patient-perceived position of the upper lip (Labrale superious) and chin (Pogonion) and the actual position of their upper lip and chin were measured on two occasions. Intra-patient reproducibility was found to be excellent (ICC 0.93 to 0.98). All differences were statistically significantly greater than 3mm, and would be clinically significant. Patients were better at re-creating their AP chin position rather than their AP upper lip and vertical chin positions. Approximately half of patients undergoing surgical correction of their class III skeletal pattern were unable to correctly identify their pre-surgical facial profile. Given the lack of awareness of their profile, this questions the validity of using profile planning for informed consent. [ABSTRACT FROM AUTHOR]

Fabrication of conventional facial prostheses is a labor-intensive process which traditionally requires an impression of the facial defect and surrounding tissues. Inaccuracies occur during the facial moulage because of soft-tissue compression, the patient's reflex movements, or the lack of support for the impression material. A variety of 3D imaging techniques have been introduced during the production of facial prostheses. However, the accuracy of the different imaging techniques has not been evaluated sufficiently in this clinical context. The purpose of this in vitro study was to compare the difference in accuracy of capturing oncology facial defects with multimodal image fusion and laser scanning against a cone beam computed tomography (CBCT) reference scan. Ten gypsum casts of oncology facial defects were acquired. To produce reference models, a 3D volumetric scan was obtained using a CBCT scanner and converted into surface data using open-source medical segmentation software. This model was cropped to produce a CBCT mask using an open-source system for editing meshes. The multimodal image fusion model was created using stereophotogrammetry to capture the external facial features and a custom optical structured light scanner to record the defect. The gypsum casts were also scanned using a commercial 3D laser scanner to create the laser-scanned model. Analysis of the best fit of each experimental model to the CBCT mask was performed in MeshLab. The unsigned mean distance was used to measure the absolute deviation of each model from the CBCT mask. A paired-samples t test was conducted to compare the mean global deviation of the 2 imaging modalities from the CBCT masks (α=.05). A statistically significant difference was found in the mean global deviation between the multimodal imaging model (220 ±50 μm) and the laser-scanned model (170 ±70 μm); (t(9)=2.56, P =.031). The color error maps illustrated that the greatest error was located at sites distant to the prosthesis margins. The laser-scanned models were more accurate; however, the mean difference of 50 μm is unlikely to be clinically significant. The laser scanner had limited viewing angles and a longer scan time which may limit its transferability to maxillofacial practice. [ABSTRACT FROM AUTHOR]

After orthognathic surgery the forehead remains unchanged. To produce facial harmony, the planned projection of the maxillomandibular complex must be placed in the correct relations to the unchanged position of the forehead. We have compared the anterior soft tissue projection of the maxillomandibular complex relative to the forehead after Le Fort I advancement surgery for correction of maxillary hypoplasia with that of a local reference group chosen by lay assessors. We retrospectively studied 32 patients (16 men and 16 women) all of whom had previously been treated by Le Fort I maxillary advancement. In addition a panel of 8 lay assessors selected a reference group of 24 women and 16 men. Standard profile photographs were taken, and horizontal measurements made, of several landmarks from a true vertical line (TV) passing through glabella. Together with facial harmony values these were compared between the groups. The orthognathic group had significantly more anterior mandibular projection relative to the forehead than the female reference group (p = 0.03). As a result half of the horizontal harmony values were smaller in the orthognathic group. For men the position of the mandible, particularly the chin, was acceptable even though it was positioned more anteriorly. We have provided values for maxillomandibular projection derived from lay assessors and identified areas where differences from those of a reference group were detected. The projection of the mid and lower face of the local reference group to the forehead should guide preoperative planning. [ABSTRACT FROM AUTHOR]

This study was carried out on volunteers to evaluate a newly developed interactive software package aimed at informing prospective Le Fort I osteotomy patients regarding the surgical technique and possible complications. The aim of the study was to compare two methods of information delivery; a multi-media tablet device delivering both graphic and verbal information, and an audio device delivering essentially the same information in verbal form only. The null hypothesis was that there would be no difference between the efficiencies of the two methods. The subjects' ability to recall the information delivered by both devices was assessed using a questionnaire. The tablet device participants scored an average of 15.48 points, while the audio device participants scored an average of 268 points. The difference was statistically significant ( p < 0.001), suggesting that the multi-media tablet device was more effective method. [ABSTRACT FROM AUTHOR]

Computer packages have been introduced to simulate the movements of the jaw in three dimensions to facilitate planning of treatment. After final 3-dimensional virtual planning, a rapid prototype wafer can be manufactured and used in theatre. Our aim was to assess the accuracy of rapid prototyping of virtual wafers derived from laser scanned dental models using CAD/CAM software. Upper and lower plaster models from 10 orthognathic patients, the articulated models, and the conventional wafers were scanned. The virtual wafers were made from CAD/CAM software, and printed on a stereolithographic printer. We also scanned the articulated models with rapid prototype wafers in place. The validity of the final rapid prototype wafer was measured by the accuracy with which upper and lower models related to one another. The absolute mean error of the rapid prototype wafer when aligned with the dental models was 0.94 (0.09) mm. The absolute distance of the 2 models articulated by conventional and rapid prototype wafers ranged from 0.04 - 1.73mm. The rapid prototype wafers were able to orientate the upper and lower dental models with an absolute mean error of 0.94 (0.09) mm, but it ranged from 0.04-1.73mm. [ABSTRACT FROM AUTHOR]

Summary: Background: To date breast assessment has been conducted mainly subjectively. However lately validated objective three-dimensional (3D) imaging was developed. The study aimed to assess breast reconstruction subjectively and objectively and conduct a comparison. Methods: In forty-four patients after immediate unilateral breast reconstruction with solely the extended latissimus dorsi flap the breast was captured by validated 3D imaging method and standardized 2D photography. Breast symmetry was subjectively evaluated by six experts who applied the Harris score giving a mark of 1–4 for a poor to excellent result. An error study was conducted by examination of the intra and inter-observer agreement and agreement on controls. By Procrustes analysis an objective asymmetry score was obtained and compared to the subjective assessment. Results: The subjective assessment showed that the inter-observer agreement was good or substantial (p-value: <0.0001). There was moderate agreement on the controls (p-value: <0.0001) and fair (p-values: 0.159, 0.134, 0.099) to substantial (p-value: 0.005) intra-observer agreement. The objective assessment revealed that the reconstructed breast showed a significantly smaller volume compared to the opposite side and that the average asymmetry score was 0.052, ranging from 0.019 to 0.136. When comparing the subjective and objective method the relationship between the two scores was highly significant. Conclusion: Subjective breast assessment lacked accuracy and reproducibility. This was the first error study of subjective breast assessment versus an objective validated 3D imaging method based on true 3D parameters. The substantial agreement between established subjective breast assessment and new validated objective method supported the value of the later and we expect its future role to expand. [Copyright &y& Elsevier]

Summary: Background: The latissimus dorsi muscle flap is a common method for the reconstruction of the breast following mastectomy. The study aimed to assess the quality of this reconstruction using a three-dimensional (3D) imaging method. The null hypothesis was that there was no difference in volume between the reconstructed breast and the opposite side. Methods: This study was conducted in forty-four patients who had had immediate unilateral breast reconstruction by latissimus dorsi muscle flap. The breast was captured using the 3D imaging system. Ten landmarks were digitised on the 3D images. The volume of each breast was measured by the application of Breast Analysis Tool software. The symmetry of the breast was measured using Procrustes analysis. The impact of breast position, orientation, size and intrinsic shape on the overall breast asymmetry was investigated. Results: The null hypothesis was rejected. The reconstructed breast showed a significantly smaller volume when compared to the opposite side, p < 0.0001, a mean difference of 176.8 cc and 95% CI (103.5, 250.0). The shape and the position of the reconstructed breast were the main contributing factors to the measured asymmetry score. Conclusions: 3D imaging was efficient in evaluating the outcome of breast surgery. The latissimus dorsi muscle flap on its own for breast reconstruction did not restore the volume and shape of the breast fully lost due to complete mastectomy. The modification of this method and the selection of other or additional surgical techniques for breast reconstruction should be considered. The asymmetry analysis through reflection and Procrustes matching was a useful method for the objective shape analysis of the female breast and presented a new approach for breast shape assessment. The intrinsic breast shape and the positioning of the breast were major components of postoperative breast asymmetry. The reconstructed breast was smaller overall than the un-operated breast at a significant level when assessing the breast volume using the surface area. 3D imaging by multiple stereophotogrammetry was a useful tool for volume measurements, shape analysis and the evaluation of symmetry. [Copyright &y& Elsevier]

Abstract: The quality of care delivered to 74 patients undergoing orthognathic surgery was assessed using a patient satisfaction questionnaire and data collected from hospital case records. Surgical complications, hospital services, patient satisfaction, and impact on quality of life, were the main aspects considered. The majority of patients reported that their treatment objectives had been achieved and that they were satisfied with the quality of care provided. The main concern of the patients regarding the clinic was the waiting time before an appointment could be offered. Eating and breathing difficulties and low mood after surgery were the main reported complications. Sixty-three patients experienced post-operative weight loss. The importance of a nutritious, high calorie soft diet should be emphasised and the use of menthol inhalations following maxillary osteotomies should be considered more frequently. Clinicians should be aware of post-operative low mood, which may require psychological support. We developed a sensitive assessment battery with comprehensive parameters to audit quality of orthognathic surgery service, and recommend that a similar approach should be considered by teams which undertake management of orthognathic patients. [Copyright &y& Elsevier]

Summary: Background: The aim of this study was to evaluate the validity of a three-dimensional (3D) multiple stereo camera system for objective breast assessment. Methods: A multiple stereo camera system, which consisted of four pods and eight cameras, two cameras on each pod, developed by Glasgow University, was used. Nine specially shaped plaster breast models were captured once, 3Dmodels were constructed and the volume of each plaster model was measured 10 times by the breast analysis tool (BAT) software. A comparison was conducted with water displacement method, and measurements were repeated 10 times. The breast of six live volunteers was captured six times; from each breast capture, a 3D model was constructed and the volume was measured with BAT software. Breast volume assessment by the water displacement method was repeated six times. Results: In all plaster casts, the discrepancies in volume measurements between 3D imaging and water displacement methods did not exceed 40cc. The overall mean relative difference was 5%. The differences of the two methods were not significant at p =0.189, overall mean difference: 11.1cc and 95% confidence interval (CI) was (−6.732, 28.976). In the live models, the differences in breast volume measurements between the 3D imaging and water displacement methods were significant at p ≤0.017, overall mean difference: 207.05cc and 95% CI (56.12, 357.98). Measurements by 3D imaging were consistently smaller. In the live models, 3D imaging overall was a more reproducible method for measuring breast volume than the water displacement method with a standard deviation of 36 units cc−1 and 62.6 units cc−1, respectively. Conclusions: The 3D breast imaging system using multiple stereo cameras was accurate for measuring the volumes of breast-shaped plaster models, and it was more reproducible than the water displacement method in live models. 3D imaging is a reliable method for the comparative assessment of breast volume. [Copyright &y& Elsevier]

Introduction: The objective of this 2-arm parallel trial was to investigate the recall and comprehension of the information of orthodontic patients undergoing fixed orthodontic treatment using either the verbal explanation supported with the British Orthodontic Society (BOS) leaflet or 3-dimensional (3D) animated content.Methods: Patients aged 12-18 years, with no relevant medical history or learning and reading difficulties, who were to undergo orthodontic treatment, were randomized to receive information about fixed orthodontic treatment, using either verbal explanation supported with the BOS leaflet or 3D animated content on the basis of the BOS leaflet. Randomization was performed by block randomization; block size of 4 was used, from which 6 blocks with 6 different sequences (AABB, ABBA, ABAB, BBAA, BAAB, BABA). The blinded author asked patients a series of open-ended questions. The primary outcome measure was the total score of the questions. An independent 2 sample t test was conducted to determine if there was a statistical difference in total questions score between the conventional method (verbal and leaflet) and the 3D animation at the time of consent taking (T0) and again 1 year later (T1). The secondary outcome measure was the time spent by the clinician delivering the information to the patient.Results: Thirty-two patients were randomized into each group. After 1 year, 1 patient was lost in each group. At the time of consent, the conventional group scored 79.1 ± 18.4 compared with 76.4 ± 12.8 for the 3D animation group with no statistically significant difference (95% confidence interval, -11.0 to 5.3), (P = 0.492). One year later, again, there was no statistically significant difference (P = 0.639) between the conventional group (75.6 ± 12.3) and the 3D animation group (74.4 ± 9.0) (95% confidence interval, -7.0 to 4.4). The average exposure time to the educational intervention in the conventional group was 8.5 minutes more than the 3D animation group.Conclusions: The use of 3D animation or verbal and leaflet information is relatively equivalent in transferring knowledge to the orthodontic patient. The use of a 3D animated video reduces the clinician time needed in the clinic to deliver information to the patients and also allows multiple views and better suits the younger generation. Patients undergoing short- or long-term orthodontic treatment do not recall root damage as a risk of orthodontic treatment, which requires special attention from the orthodontist to reinforce this information.Registration: This trial was not registered.Protocol: The protocol was not published before trial commencement. [ABSTRACT FROM AUTHOR]

Aim: Assess the feasibility, validity and precision of multimodal image fusion to capture oncology facial defects based on plaster casts.Methods: Ten casts of oncology facial defects were acquired. To create gold standard models, a 3D volumetric scan of each cast was obtained with a cone beam computed tomography (CBCT) scanner (NewTomVG). This was converted into surface data using open-source medical segmentation software and cropped to produce a CBCT mask using an open-source system for editing meshes. For the experimental model, the external facial features were captured using stereophotogrammetry (DI4D) and the defect was recorded with a custom optical structured light scanner. The two meshes were aligned, merged and resurfaced using MeshLab to produce a fused model. Analysis was performed in MeshLab on the best fit of the fused model to the CBCT mask. The unsigned mean distance was used to measure the absolute deviation of each model from the CBCT mask. To assess the precision of the technique, the process of producing the fused model was repeated to create five models each for the casts representing the best, middle and worst results.Results: Global mean deviation was 0.22 mm (standard deviation 0.05 mm). The precision of the method appeared to be acceptable although there was variability in the location of the error for the worst cast.Conclusion: This method for merging two independent scans to produce a fused model shows strong potential as an accurate and repeatable method of capturing facial defects. Further research is required to explore its clinical use. [ABSTRACT FROM AUTHOR]

Summary: Background: Errors derive from the variability seen in the repeat volume measurements for a particular individual. The aim of this study was to evaluate the variation and errors of a three-dimensional (3D) multiple stereo camera system for objective breast assessment. It was also investigated whether there was any correlation between these errors and the size of the breast. Methods: A prototype eight camera multiple stereophotogrammetry system was utilized. The volumes of nine plaster breast models were determined by 3D imaging and the correlation between the size of the models and the variability of the measurements was investigated after ten repeats. The breasts of six live volunteers were examined following a specific protocol. The breasts were captured six times, three times each on two different occasions; from each breast capture a three-dimensional model was built and the breast volume was measured three times with breast analysis tool (BAT) software. This allowed for an assessment of the variability introduced at each stage of the measurement procedure. The correlation between the size of the breast and the variability of the measurements was investigated. Results of volume measurements by water displacement method, repeated ten times with the plaster models and six times with the live models, were used for comparison. Results: The correlation between the size of the plaster models and the variability of the measurements revealed a significant correlation (p = 0.033), indicating that the larger the model, the more variable were the results. The correlation between the size of the breasts in the live models and the variability of the results revealed a non-significant correlation (p = 0.342), but there was a visible trend that the larger breasts showed more variable results. The average variation in the repeated measurements on each individual was found to be 32.95 cc across the two different poses, 19.43 cc across the various captures, and 28.32 across the different volume calculations with the BAT software. The error is less than what is clinically visible with the human eye, which is about 50 cc variation in volume by subjective assessment. As a proportion of the mean volume, namely 6.9%, 4.0% and 5.9% respectably, the values are small and indicate that the reproducibility of the system is good. Conclusion: The 3D imaging system using multiple stereo cameras revealed a positive correlation between the size of plaster models and the breasts of live models and the reproducibility of the measurements, indicating that the variation was higher for the larger sizes. The relationship was significant in the plaster models but not in the live models, although a trend was observed. The assessment of the variation and errors of the system was part of the necessary procedure that should be considered for the validation of any new measurement technology for breast assessment. [Copyright &y& Elsevier]

Abstract: Objective: To investigate a registration approach for 2-dimension (2D) based on characteristic localization to achieve 3-dimension (3D) fusion from images of PET, CT and MR one by one. Method: A cubic oriented scheme of“9-point & 3-plane” for co-registration design was verified to be geometrically practical. After acquisiting DICOM data of PET/CT/MR (directed by radiotracer 18F-FDG etc.), through 3D reconstruction and virtual dissection, human internal feature points were sorted to combine with preselected external feature points for matching process. By following the procedure of feature extraction and image mapping, “picking points to form planes” and “picking planes for segmentation” were executed. Eventually, image fusion was implemented at real-time workstation mimics based on auto-fuse techniques so called “information exchange” and “signal overlay”. Result: The 2D and 3D images fused across modalities of [CT+MR], [PET+MR], [PET+CT] and [PET+CT+MR] were tested on data of patients suffered from tumors. Complementary 2D/3D images simultaneously presenting metabolic activities and anatomic structures were created with detectable-rate of 70%, 56%, 54% (or 98%) and 44% with no significant difference for each in statistics. Conclusion: Currently, based on the condition that there is no complete hybrid detector integrated of triple-module [PET+CT+MR] internationally, this sort of multiple modality fusion is doubtlessly an essential complement for the existing function of single modality imaging. [Copyright &y& Elsevier]