Mixed reality-based technology to visualize and facilitate treatment planning of impacted teeth: Proof of concept.

OBJECTIVE We propose a method utilizing mixed reality (MR) goggles (HoloLens 2, Microsoft) to facilitate impacted canine alignment, as planning the traction direction and force delivery could benefit from 3D data visualization using mixed reality (MR). METHODS Cone-beam CT scans featuring isometric resolution and low noise-to-signal ratio were semi-automatically segmented in Inobitec software. The exported 3D mesh (OBJ file) was then optimized for the HoloLens 2. Using the Unreal Engine environment, we developed an application for the HoloLens 2, implementing HoloLens SDK and UX Tools. Adjustable pointers were added for planning attachment placement, traction direction, and point of force application. The visualization was presented to participants of a course on impacted teeth treatment, followed by a 10-question survey addressing potential advantages (5-point scale: 1 = totally agree, 5 = totally disagree). RESULTS Out of 38 respondents, 44.7% were orthodontists, 34.2% dentists, 15.8% dental students, and 5.3% dental technicians. Most respondents (44.7%) were between 35 and 44 years old, and only 1 (2.6%) respondent was 55-64 years old. Median answers for six questions were 'totally agree' (25th percentile 1, 75th percentile 2) and for four questions 'agree' (25th percentile 1, 75th percentile 2). No correlation was found between age, profession, and responses. CONCLUSION Our method generated substantial interest among clinicians. The initial responses affirm the potential benefits, supporting the continued exploration of MR-based techniques for the treatment of impacted teeth. However, the recommendation for widespread use awaits validation through clinical trials

The Slavcleft: a three-center study of the outcome of treatment of cleft lip and palate. Nasolabial appearance.

Background There is a multitude of protocols of treatment of cleft lip and palate (CLP) worldwide differing in number of operations, surgical techniques, and timings of surgeries. Despite, facial appearance in subjects with CLP is rarely ideal and residual stigmata are easy to notice in many patients irrespective of the protocol. The prospective controlled investigations are optimal for comparing effectiveness of treatment protocols. Because prospective studies are very challenging to perform in CLP field, it is reasonable to retrospectively assess different surgical protocols to identify the promising ones and then to test them in a prospective way. Methods Our objective was to assess the nasolabial appearance in a preadolescent Slavic population with unilateral cleft lip and palate (UCLP) by using the 0-200 numeric scale with reference photographs. Patients treated in Warsaw, Poland (n = 32), Prague, Czech Republic (n = 26) and Bratislava, Slovakia (n = 17) were included in this retrospective study. Each cleft center used a unique surgical protocol. Two panels of professional raters (n = 7) and laypeople (n = 10) scored blindly the nasolabial esthetics on cropped frontal and profile images with cropped reference photograph present on the same slide. Intra- and inter-rater agreement was assessed with Cronbach's alpha, intraclass correlation coefficients, t-tests, and Bland-Altman plots. Inter-group differences were evaluated with one-way ANOVA and regression analysis. Results The agreement within and between raters was acceptable. We found that patients treated in Warsaw, Prague, and Bratislava showed comparable nasolabial appearance on frontal and profile photographs when judged by both professional raters (p > 0.05) and laypeople (p > 0.05). Regression analysis did not identify influence of gender, group (i.e., Warsaw, Prague, and Bratislava), age at lip repair, surgeon, and age at photographic assessment on esthetic outcome (p > 0.05). Conclusion This study showed that none of the surgical protocols showed superiority to produce good nasolabial appearance

Alveolar bone grafting in unilateral cleft lip and palate : impact of timing on palatal shape

Alveolar bone grafting (ABG) is a critical surgical intervention in patients with a cleft of the alveolus, aimed at reconstructing the alveolar ridge to facilitate proper eruption, periodontal support, and alignment of adjacent permanent teeth. The optimal timing for ABG remains debated, with late secondary ABG between the ages of 9 and 11 being widely adopted. This study compared the palatal shapes of 28 children at a mean age of 9.5 years (SD = 0.7) who underwent early secondary ABG at a mean age of 2.1 years (SD = 0.6) or 33 children at a mean age of 10.8 years (SD = 1.5) who underwent late secondary ABG at a mean age of 8.6 years (SD = 1.3) to 60 non-cleft controls at a mean age of 8.6 years (SD = 1.2). The palatal shapes were captured with 239 landmarks digitized on the palate on a digital model. Utilizing geometric morphometric methods, i.e., generalized Procrustes superimpositions, principal component analysis, and permutation tests, we assessed the impact of ABG timing on palatal morphology. The first five principal components (PCs) explained 64.1% of the total shape variability: PC1 = 26.1%; PC2 = 12%; PC3 = 11.9%; PC4 = 7.8%; and PC5 = 6.4%. The Procrustes distance between both cleft groups and the control group was more than twice as large as the Procrustes distance between the early ABG and late ABG groups. Nonetheless, all intergroup differences were statistically significant. Our findings suggest that early ABG has a limited negative effect on palatal shape, providing comparable outcomes to late ABG. The study highlights the potential suitability of early ABG, challenging conventional practices and encouraging further exploration into its long-term effects on maxillary growth.</p

The Slav-cleft: A three-center study of the outcome of treatment of cleft lip and palate. Part 1: Craniofacial morphology

Results of a comparison of the outcomes of treatment of cleft lip and palate can be affected by growth characteristics of populations from which subjects with the clefts are derived. Moreover, conventional cephalometric techniques used in cleft studies for analysis of facial morphology provide only a partial description of shape and are confounded by biases regarding the reference structures. In this retrospective comparison, craniofacial morphology of preadolescent patients with unilateral cleft lip and palate treated in Warsaw (n = 35, age = 10.6 years, SD = 1.2), Prague (n = 38, age = 11.6 years, SD = 1.4), and Bratislava (n = 26, age = 10.5 years, SD = 1.6) were evaluated on cephalograms with the cephalometric method used in the Eurocleft study and geometric morphometrics. We found that patients treated in Warsaw showed slightly more favorable outcomes than in Prague and Bratislava. The differences were related primarily to the position of maxillary alveolar process, cranial base, mandibular angle, and soft tissues. Although no association between a component of treatment protocol and the outcome was found, it is possible that organizational factors such as participation of high-volume, experienced surgeons contributed to these results. (C) 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved

The Slavcleft: A three-center study of the outcome of treatment of cleft lip and palate. Part 2: Dental arch relationships.

PURPOSE Our aim was to evaluate the dental arch relationship in a preadolescent Slavic population with unilateral cleft lip and palate (UCLP) by using the Goslon Yardstick. MATERIALS AND METHODS Patients treated in Warsaw, Poland (n = 32), Prague, Czech Republic (n = 33) and Bratislava, Slovakia (n = 30) were included in this retrospective study. Each cleft center used a unique surgical protocol. Three raters scored blindly the dental arch relationship on plaster models. Intra- and inter-rater agreement were assessed with kappa statistics, and differences between the groups were evaluated with one-way analysis of variance. Intra-rater agreement was very good (k > 0.825), while inter-rater agreement was either good or very good (kappa >0.703). RESULTS We found that patients treated in Warsaw showed a more favorable dental arch relationship (Goslon score = 2.58, SD = 0.77) than patients treated in Prague (Goslon score = 3.21, SD = 1.04). Patients treated in Bratislava showed an intermediate Goslon score (3.07; SD = 0.99). CONCLUSION This study showed that the dental arch relationships in patients treated in Warsaw with a one-stage repair were more favorable than in patients treated in Prague and Bratislava with a two-stage protocol and comparable to the best results obtained in the Eurocleft and Americleft studies

The Slavcleft: A Three-Center Study of the Outcome of Treatment of Cleft Lip and Palate Considering Palatal Shape

The degree of deviation of palatal shape from the norm may reflect facial growth disturbance in cleft lip and palate (CLP). The objective of this study was to compare the palatal morphology in children treated with different surgical protocols. Palatal shape was assessed with geometric morphometrics (GM) including Procrustes superimposition, principal component analysis (PCA), and permutation tests with 10,000 permutations, in 24 children treated with two-stage repair with a late palatoplasty (Prague group; mean age at assessment 8.9 years), 16 children after two-stage repair with early palatoplasty (Bratislava group; mean age 8.2 years), and 53 children treated with a one-stage repair (Warsaw group, mean age 10.3 years). The non-cleft control group comprised 60 children at 8.6 years. The first five principal components (PCs) accounted for a minimum of 5% of the total shape variability (65.9% in total). The Procrustes distance was largest for the Prague vs. Control pair and smallest for the Prague vs. Bratislava pair. Nonetheless, all intergroup differences were statistically significant (p < 0.01). One can conclude that variations in palatal shape roughly correspond to cephalometric and dental arch relationship findings from prior research. Among the children who underwent a one-stage repair of the complete cleft, their palatal morphology most closely resembled that of the non-cleft controls. Conversely, children who received late palatoplasty exhibited the greatest degree of deviation