Does facial asymmetry vary between subjects of different age groups? A 3D stereophotogrammetry analysis.

This study was aimed to assess whether facial asymmetry increases with age and to examine potential gender differences using 3D stereophotogrammetry. A prospective cross-sectional study was performed. 3D photographs were acquired from 600 control subjects, 300 male, 300 female, and were stratified into 15 different age groups ranging from 0 to 70+. The 3D photographs were postprocessed and mirrored. The original and mirrored faces were surface-based matched using an iterative closest point algorithm. The primary outcome variable, facial asymmetry, was evaluated by calculating the absolute mean distance between the original and mirrored images. The primary predictor was age. Pearson's correlation was used to assess the correlation between facial asymmetry and age. The average overall facial asymmetry was 0.72 mm (SD 0.72 mm; range 0.25 - 3.04 mm). Mean facial asymmetry increased significantly with age, from 0.45 mm in the age group of 0-4 years to 0.98 mm in the age group of 70+ (p<0.001). Facial asymmetry was positively correlated with age (Pearson's r = 0.55; p<0.001). Male subjects were significantly more asymmetric compared to females, 0.77 mm and 0.67 mm, respectively (p<0.001). This study indicates that facial asymmetry significantly increases with age and is significantly larger in males than in females.

Nasolabial shape and aesthetics in unilateral cleft lip and palate: an analysis of nasolabial shape using a mean 3D facial template.

The aim of this study was to determine the amount of deviation in nasolabial shape in patients with a cleft compared with an average non-cleft face, and to assess whether this difference is related to nasolabial aesthetics. Three-dimensional stereophotogrammetric images of 60 patients with a unilateral cleft were used. To quantify shape differences, four average non-cleft faces were constructed from stereophotogrammetric images of 141 girls and 60 boys. Three-dimensional shape differences were calculated between superimposed cleft faces and the average non-cleft face for the same sex and age group. Nasolabial aesthetics were rated with the modified Asher-McDade Aesthetic Index using a visual analogue scale (VAS). Mean VAS scores ranged from 51.44 to 60.21 for clefts, with lower aesthetic ratings associated with increasing cleft severity. Shape differences were found between cleft faces and the average non-cleft face. No relationship was found for the VAS, age, and sex, except that a lower VAS was related to a higher nose and lip distance between the superimposed cleft and average non-cleft faces for nasal profile (P= 0.02), but the explained variance was low (R2=0.066). In conclusion, except for nasal profile, nasolabial aesthetics were not influenced by the extent of shape differences from the average non-cleft face.

Oral & Maxillofacial surgery is ready for patient-centred eHealth interventions - the outcomes of a scoping review.

Within the field of oral and maxillofacial (OMF) surgery, eHealth is expected to be a tool to improve quality of care. The aim of this study is to map the research of patient-centred eHealth interventions within OMF surgery by means of a scoping review. After a systematic literature search, relevant studies on patient-centred eHealth interventions for OMF-surgery patients were selected. The interventions were mapped based on their key components, target population and outcome measures. To gain insight in the research phase of evaluation, the framework of the Medical Research Council (MRC) was used. Forty-one papers were included, comprising 34 unique interventions. Nineteen interventions were designed for head and neck cancer patients, 11 interventions concernd video-teleconsultation. According to the MRC framework, 26 papers fitted into the feasibility and piloting phase of research, 8 into the evaluation phase, 7 were in the development phase. No implementation studies were found. This scoping review can be a starting point for those who are interested in applying and evaluating eHealth in their practice. Since many feasibility and pilot studies were found on similar interventions, a more extensive collaboration with and connecting to each other is recommended to catalyze the implementation of eHealth in daily practice. Profound involvement of patients in developing and evaluating eHealth interventions is essential to achieve true patient-centred OMF surgery.

A new method for three-dimensional evaluation of the cranial shape and the automatic identification of craniosynostosis using 3D stereophotogrammetry.

Craniosynostosis is a congenital defect which can result in abnormal cranial morphology. Three dimensional (3D) stereophotogrammetry is potentially an ideal technique for the evaluation of cranial morphology and diagnosis of craniosynostosis because it is fast and harmless. This study presents a new method for objective characterization of the morphological abnormalities of scaphocephaly and trigonocephaly patients using 3D photographs of patients and healthy controls. Sixty 3D photographs of healthy controls in the age range of 3-6 months were superimposed and scaled. Principal component analysis (PCA) was applied to find the mean cranial shape and the cranial shape variation in this normal population. 3D photographs of 20 scaphocephaly and 20 trigonocephaly patients were analysed by this PCA model to test whether cranial deformities of scaphocephaly and trigonocephaly patients could be objectively identified. PCA was used to find the mean cranial shape and the cranial shape variation in the normal population. The PCA model was able to significantly distinguish scaphocephaly and trigonocephaly patients from the normal population. 3D stereophotogrammetry in combination with the presented method can be used to objectively identify and classify the cranial shape of healthy newborns, scaphocephaly and trigonocephaly patients.

An accuracy study of computer-planned implant placement in the augmented maxilla using osteosynthesis screws.

Previous research on the accuracy of flapless implant placement of virtually planned implants in the augmented maxilla revealed unfavourable discrepancies between implant planning and placement. By using the osteosynthesis screws placed during the augmentation procedure, the surgical template could be optimally stabilized. The purpose of this study was to validate this method by evaluating its clinically relevant accuracy. Twelve consecutive fully edentulous patients with extreme resorption of the maxilla were treated with a bone augmentation procedure. Virtual implant planning was performed and a surgical template was manufactured. Subsequently, six implants were installed using the surgical template, which was only supported by the osteosynthesis screws. Implant deviations between planning and placement were calculated. A total of 72 implants were installed. Mean deviations found in the mesiodistal direction were 0.817mm at the implant tip and 0.528mm at the implant shoulder. The angular deviation was 2.924°. In the buccolingual direction, a deviation of 1.038mm was registered at the implant tip and 0.633mm at the implant shoulder. The angular deviation was 3.440°. This study showed that implant placement in the augmented maxilla using a surgical template supported by osteosynthesis screws is accurate.

Three-dimensional evaluation of the alar cinch suture after Le Fort I osteotomy.

Orthognathic surgery has an influence on the overlying soft tissues of the translated bony maxillomandibular complex. Improvements in both function and facial appearance are the goals of surgery. However, unwanted changes to the soft tissues, especially in the nose region, frequently occur. The most common secondary change in the nasolabial region is widening of the alar base. Various surgical techniques have been developed to minimize this effect. The purpose of this study was to evaluate the changes in the nasal region due to orthognathic surgery, especially the alar width and nasal volume, using combined cone beam computed tomography (CBCT) and three-dimensional (3D) stereophotogrammetry datasets. Twenty-six patients who underwent a Le Fort I advancement osteotomy between 2006 and 2013 were included. From 2006 to 2010, no alar base cinch sutures were performed. From 2010 onwards, alar base cinch sutures were used. Preoperative and postoperative documentation consisted of 3D stereophotogrammetry and CBCT scans. 3D measurements were performed on the combined datasets, and the alar base width and nose volume were analyzed. No difference in alar base width or nose volume was observed between patients who had undergone an alar cinch and those who had not. Postoperatively the nose widened and the volume increased in both groups.

Use of a modified Furlow Z-plasty as a secondary cleft palate repair procedure to reduce velopharyngeal insufficiency.

Cleft palate repair is done to allow for normal speech by separating the oral and nasal cavities and creating a functioning velopharyngeal valve. However, despite cleft palate repair, some patients demonstrate velopharyngeal insufficiency (VPI). An attempt was made to determine the effectiveness of a modified secondary Furlow Z-plasty in improving VPI. Fifty-five children aged between 12 and 15 years, with postoperative VPI following primary palatoplasty, were included in the study. These children underwent a modified Furlow Z-plasty. Nasometry was done to determine the change in velopharyngeal function due to the secondary Furlow Z-plasty by comparing the preoperative with the 1-year postoperative nasalance scores. A test-retest study was performed to determine the reliability of the nasometric measures. Reliability measurements of the nasometer passages revealed good reliability for 18 out of the 25 speech passages. There was a statistically significant reduction in VPI at 1 year postoperative in patients who were treated with the modified Furlow Z-plasty, with a P-value of <0.001 in all passages, except velar plosives, which had a P-value of 0.002. Patients with VPI after primary palatoplasty and treated using a modified Furlow Z-plasty had significantly lower nasalance scores at 1 year postoperative, indicating significantly improved velopharyngeal function.

Clinical relevance of cone beam computed tomography in mandibular third molar removal: A multicentre, randomised, controlled trial.

PURPOSE: The aims of this study were to investigate the effectiveness of cone beam computed tomography (CBCT) compared to panoramic radiography (PR), prior to mandibular third molar removal, in reducing patient morbidity, and to identify risk factors associated with inferior alveolar nerve (IAN) injury. MATERIAL AND METHODS: This multicentre, randomised, controlled trial was performed at three centres in the Netherlands. Adults with an increased risk for IAN injury, as diagnosed from PR, were included in the study. In one arm of the study, patients underwent an additional CBCT prior to third molar surgery. In a second arm of the study, no additional radiographs were acquired. The primary outcome measure was the number of patient-reported altered sensations 1 week after surgery. As secondary outcome measures, the number of patients with objective IAN injury, with long-term (>6 months) IAN injury, the occurrence of other postoperative complications, the Oral Health Related Quality of Life-14 (OHIP-14) questionnaire responses, postoperative pain (visual analogue scale score), duration of surgery, number of emergency visits, and number of missed days of work or study were scored. RESULTS: A total of 268 patients with 320 mandibular third molars were analysed according to the intention-to-treat principle. The overall incidence of IAN injury 1 week after surgery was 6.3%. No significant differences between CBCT and PR for temporary IAN injury (p = 0.64) and all other secondary outcomes were registered. A lingual position of the mandibular canal (MC) and narrowing, in which the diameter of the MC lumen was decreased at the contact area between the MC and the roots, were significant risk factors for temporary IAN injury. CONCLUSION: Although CBCT is a valuable diagnostic adjunct for identification of an increased risk for IAN injury, the use of CBCT does not translate into a reduction of IAN injury and other postoperative complications, after removal of the complete mandibular third molar. In these selected cases of a high risk for IAN injury, an alternative strategy, such as monitoring or a coronectomy, might be more appropriate. (http://clinicaltrials.gov, NCT02071030).

Development of a Three-Dimensional Hand Model Using Three-Dimensional Stereophotogrammetry: Assessment of Image Reproducibility.

PURPOSE: Using three-dimensional (3D) stereophotogrammetry precise images and reconstructions of the human body can be produced. Over the last few years, this technique is mainly being developed in the field of maxillofacial reconstructive surgery, creating fusion images with computed tomography (CT) data for precise planning and prediction of treatment outcome. Though, in hand surgery 3D stereophotogrammetry is not yet being used in clinical settings. METHODS: A total of 34 three-dimensional hand photographs were analyzed to investigate the reproducibility. For every individual, 3D photographs were captured at two different time points (baseline T0 and one week later T1). Using two different registration methods, the reproducibility of the methods was analyzed. Furthermore, the differences between 3D photos of men and women were compared in a distance map as a first clinical pilot testing our registration method. RESULTS: The absolute mean registration error for the complete hand was 1.46 mm. This reduced to an error of 0.56 mm isolating the region to the palm of the hand. When comparing hands of both sexes, it was seen that the male hand was larger (broader base and longer fingers) than the female hand. CONCLUSIONS: This study shows that 3D stereophotogrammetry can produce reproducible images of the hand without harmful side effects for the patient, so proving to be a reliable method for soft tissue analysis. Its potential use in everyday practice of hand surgery needs to be further explored.

Evaluation of the anterior mandibular donor site one year after secondary reconstruction of an alveolar cleft: 3-dimensional analysis using cone-beam computed tomography.

The aim of this study was to analyse changes in the volume of the chin after harvest of a bone graft for secondary reconstruction of an alveolar cleft. Cone-beam computed tomographic (CT) scans of 27 patients taken preoperatively, and immediately and one year postoperatively, were analysed, and 3-dimensional hard-tissue reconstructions made. The hard-tissue segmentation of the scan taken one year postoperatively was subtracted from the segmentation of the preoperative scan to calculate the alteration in the volume of bone at the donor site (chin). A centrally-orientated persistent concavity at the buccal side of the chin was found (mean (range) 160 (0-500) mm(3)). At the lingual side of the chin, a central concavity remained (mean (range) volume 20 (0-80) mm(3)). Remarkably, at the periphery of this concavity there was overgrowth of new bone (mean (range) volume 350 (0-1600) mm(3)). Re-attachment of the muscles of the tongue resulted in a significantly larger central lingual defect one year postoperatively (p=0.01). We also measured minor alterations in volume of the chin at one year. Whether these alterations influence facial appearance and long term bony quality is to be the subject of further research.

Development of a three-dimensional hand model using 3D stereophotogrammetry: Evaluation of landmark reproducibility.

BACKGROUND: Using three-dimensional (3D) photography, exact images of the human body can be produced. Over the last few years, this technique is mainly being developed in the field of maxillofacial reconstructive surgery, creating fusion images with computed tomography (CT) data for accurate planning and prediction of treatment outcome. However, in hand surgery, 3D photography is not yet being used in clinical settings. METHODS: The aim of this study was to develop a valid method for imaging the hand using 3D stereophotogrammetry. The reproducibility of 30 soft tissue landmarks was determined using 3D stereophotogrammetric images. Analysis was performed by two observers on 20 3D photographs. Reproducibility and reliability of the landmark identification were determined using statistical analysis. RESULTS: The intra- and interobserver reproducibility of the landmarks were high. This study showed a high reliability coefficient for intraobserver (1.00) and interobserver reliability (0.99). Identification of the landmarks on the palmar aspect of individual fingers was more precise than the identification of landmarks of the thumb. CONCLUSIONS: This study shows that 3D photography can safely produce accurate and reproducible images of the hand, which makes the technique a reliable method for soft tissue analysis. 3D images can be a helpful tool in pre- and postoperative evaluation of reconstructive trauma surgery, in aesthetic surgery of the hand, and for educational purposes. The use in everyday practice of hand surgery and the concept of fusing 3D photography images with radiologic images of the interior hand structures needs to be further explored.

The use of first stage bone augmentation screws to stabilize the surgical template in the second stage.

A new method is presented in which the osteosynthesis screws from a first stage bone augmentation of the maxilla are used to stabilize the surgical template during implant placement in the second stage. This method was evaluated in one patient and the results compared to those of previous studies. The technique presented reduces the deviations between implant planning and the final implant position due an optimal fit of the surgical template.

Three-dimensional changes in nose and upper lip volume after orthognathic surgery.

Orthognathic surgery aims to improve both the function and facial appearance of the patient. Translation of the maxillomandibular complex for correction of malocclusion is always followed by changes to the covering soft tissues, especially the nose and lips. The purpose of this study was to evaluate the changes in the nasal region and upper lip due to orthognathic surgery using combined cone beam computed tomography (CBCT) and three-dimensional (3D) stereophotogrammetry datasets. Patients who underwent a Le Fort I osteotomy, with or without a bilateral sagittal split osteotomy, were included in this study. Pre- and postoperative documentation consisted of 3D stereophotogrammetry and CBCT scans. 3D measurements were performed on the combined datasets and analyzed. Anterior translation and clockwise pitching of the maxilla led to a significant volume increase in the lip. Cranial translation of the maxilla led to an increase in the alar width. The combination of CBCT DICOM data and 3D stereophotogrammetry proved to be useful in the 3D analysis of the maxillary hard tissue changes, as well as changes in the soft tissues. Measurements could be acquired and compared to investigate the influence of maxillary movement on the soft tissues of the nose and the upper lip.

Lower border bone onlays to augment the severely atrophic (class VI) mandible in preparation for implants: a preliminary report.

We present the preliminary results of a study involving a group of consecutive patients who underwent lower border onlay grafting, limited to the symphyseal area, in preparation for implant insertion. This technique allows for maximum-sized implants, followed by prosthetic rehabilitation. The main advantage of this method is the minimal risk of damage to the mental nerve. Sixteen patients were followed for a period of 6 months to 4 years and all were free of neurosensory disturbances. Eight had a removable overdenture placed and were satisfied with the result. This surgical approach allows the patient to wear their dentures during the healing period. A further advantage of lower border grafting over intraoral upper border grafting is that mucosal dehiscences are not seen.

Three dimensional evaluation of facial asymmetry after mandibular reconstruction: validation of a new method using stereophotogrammetry.

The scientific literature is sparse on reports that evaluate facial asymmetry after mandibular reconstructive surgery objectively. The aim of this study is to introduce and validate a new method, using three dimensional (3D) stereophotogrammetry, that quantifies soft-tissue facial asymmetry in patients who have undergone mandibular reconstruction. To validate the new method, two observers applied the method on 3D photographs of five patients and five controls. An inter-observer difference of 0.04 mm (-0.08 to 0.17) was found with a measurement error of 0.13 mm. 15 3D photographs of the mandibular reconstructed patients were compared with 24 3D photographs of healthy controls. A significant difference (1.19 mm) in asymmetry was found between patients and controls. It is concluded that this new measuring method is a valid, fast and clinically applicable technique to quantify soft-tissue facial asymmetry. It is concluded that facial symmetry in patients is not restored to the level of the control group with the mandibular reconstruction method applied.

Development and reproducibility of a 3D stereophotogrammetric reference frame for facial soft tissue growth of babies and young children with and without orofacial clefts.

The aim of this study was to develop a reference frame for three dimensional (3D) facial soft tissue growth analysis in children and to determine its reproducibility. Two observers twice placed the reference frame on 39 3D-stereophotogrammetry facial images of children with orofacial clefts and control children. The observers' performances were analyzed by calculating mean distance, distance variability, and P95 between the same facial surfaces at two different time points. Correlations between observers were analyzed with Pearson's correlation coefficient. The influence of presence of a cleft, absence of one ear in the photograph, and age on the reproducibility of the reference frame was checked using Student's t test. Results of intraobserver comparisons showed a mean distance of <0.40 mm, distance variability of <0.51 mm, and P95 of <0.80 mm. For interobserver reliability, the mean distance was <0.52 mm, distance variability was <0.53 mm, and P95 was <1.10 mm. Presence of a cleft, age, and absence of one ear on the 3D photograph did not have a significant influence on the reproducibility of placing the reference frame. The children's reference frame is a reproducible method to superimpose on 3D soft tissue stereophotogrammetry photographs of growing individuals with and without orofacial clefts.

One year postoperative hard and soft tissue volumetric changes after a BSSO mandibular advancement.

In this study, cone beam computed tomography (CBCT) and three dimensional (3D) stereophotogrammetry are used to compare the 3D skeletal and soft tissue changes caused by a bilateral sagittal split osteotomy (BSSO) 1 year after a mandibular advancement. Eighteen consecutive patients with a hypoplastic mandible were treated with a BSSO according to the Hunsuck modification. Preoperatively and 1 year postoperatively, a CBCT scan was acquired and a 3D photograph. The pre- and postoperative CBCT scans were matched using voxel based registration. After registration, the mandible could be segmented in the pre- and postoperative scans. The preoperative scan was subtracted from the postoperative scan, resulting in the hard tissue difference. To investigate the soft tissue changes, the pre- and postoperative 3D photographs were registered using surface based registration. After registration the preoperative surface could be subtracted from the postoperative surface, resulting in the overall volumetric difference. As expected, a correlation between mandibular advancent and volumetric changes of the hard tissues was found. The correlation between advancement and soft tissues was weak. The labial mental fold stretched after surgery. This study proved that using 3D imaging techniques it is possible to document volumetric surgical changes accurately and objectively.

[Sclerosis of lymfangiomas in the head and neck area: evaluation with the use of stereophotogrammetry]. / Sclerosering van lymfangiomen in her hoofd-halsgebied: evaluatie door middel van stereofotogrammetrie.

Lymangiomas are congenital malformations of the lymphatic system. They can appear at any age and in any part of the body. In the head and neck area lymangiomas can give rise to functional as well as esthetic problems. Therapy consist of sclerosis, possibly followed by surgical excision. Stereophotogrammetry is a relatively new technique which, by means of superimposition of pre- and postoperative images, provides the possibility to quantify treatment results. In this paper 3 patients who underwent treatment of a lymphatic malformation and in whom treatment results were measured with stereophotogrammetry are discussed. The conclusion can be drawn that stereophotogrammetry is a promising technique for evaluation of treatment results of superficially localised lymphatic malformations that displace the skin in the head and neck area.

The clinical relevance of bifid and trifid mandibular canals.

BACKGROUND: Bifid mandibular canals (BMC) and trifid mandibular canals (TMC) are variations on the normal anatomy with incidences ranging from 0.08% to 65.0%. Such aberrations have an important clinical impact. For example, an extra mandibular canal may explain inadequate anesthesia, especially when two mandibular foramina are involved. Furthermore, during mandibular surgery, a second, or even third, neurovascular bundle may be damaged causing paresthesia, neuroma development, or bleeding. CASE REPORT: Two cases are presented in this article. One patient had a BMC on both sites, and the other patient had a TMC on one site and a BMC on the other site. DISCUSSION: Initial screening for the presence of a BMC or TMC can be executed by conventional panoramic radiography. BMCs or TMCs are diagnosed, before executing mandibular surgery; additional CBCT scanning is indicated.