Advancements in diagnosing oral potentially malignant disorders: leveraging Vision transformers for multi-class detection.

OBJECTIVES: Diagnosing oral potentially malignant disorders (OPMD) is critical to prevent oral cancer. This study aims to automatically detect and classify the most common pre-malignant oral lesions, such as leukoplakia and oral lichen planus (OLP), and distinguish them from oral squamous cell carcinomas (OSCC) and healthy oral mucosa on clinical photographs using vision transformers. METHODS: 4,161 photographs of healthy mucosa, leukoplakia, OLP, and OSCC were included. Findings were annotated pixel-wise and reviewed by three clinicians. The photographs were divided into 3,337 for training and validation and 824 for testing. The training and validation images were further divided into five folds with stratification. A Mask R-CNN with a Swin Transformer was trained five times with cross-validation, and the held-out test split was used to evaluate the model performance. The precision, F1-score, sensitivity, specificity, and accuracy were calculated. The area under the receiver operating characteristics curve (AUC) and the confusion matrix of the most effective model were presented. RESULTS: The detection of OSCC with the employed model yielded an F1 of 0.852 and AUC of 0.974. The detection of OLP had an F1 of 0.825 and AUC of 0.948. For leukoplakia the F1 was 0.796 and the AUC was 0.938. CONCLUSIONS: OSCC were effectively detected with the employed model, whereas the detection of OLP and leukoplakia was moderately effective. CLINICAL RELEVANCE: Oral cancer is often detected in advanced stages. The demonstrated technology may support the detection and observation of OPMD to lower the disease burden and identify malignant oral cavity lesions earlier.

A learning curve in 3D virtual surgical planned orthognathic surgery.

OBJECTIVES: To assess the surgical accuracy of 3D virtual surgical planned orthognathic surgery and the influence of posterior impaction and magnitude of the planned movements on a possible learning curve. MATERIALS AND METHODS: This prospective cohort study included subjects who underwent bimaxillary surgery between 2016 and 2020 at the Department of Oral and Maxillofacial Surgery of the Radboud University Medical Center, Nijmegen. 3D virtual surgical planning (VSP) was performed with CBCT data and digitalized dentition data. By using voxel-based matching with pre- and postoperative CBCT data the maxillary movements were quantified in six degrees of freedom. The primary outcome variable, surgical accuracy, was defined as the difference between the planned and achieved maxillary movement. RESULTS: Based on 124 subjects, the surgical accuracy increased annually from 2016 to 2020 in terms of vertical translations (0.82 ± 0.28 mm; p = 0.038) and yaw rotations (0.68 ± 0.22°; p = 0.028). An increase in surgical accuracy was observed when combining all six degrees of freedom (p = 0.021) and specifically between 2016 and 2020 (p = 0.004). An unfavorable learning curve was seen with posterior impaction and with a greater magnitude of movements. CONCLUSION: The present study demonstrated a significant increase in surgical accuracy annually and therefore supports the presence of a learning curve. CLINICAL RELEVANCE: Cases with planned maxillary posterior impaction and/or a great magnitude of jaw movements should be transferred from the 3D VSP with extra care to obtain a satisfactory surgical accuracy.

What is the impact of miniscrew-assisted rapid palatal expansion on the midfacial soft tissues? A prospective three-dimensional stereophotogrammetry study.

OBJECTIVES: To evaluate the midfacial soft tissue changes of the face in patients treated with miniscrew-assisted rapid palatal expansion (MARPE). MATERIALS AND METHODS: 3D facial images and intra-oral scans (IOS) were obtained before expansion (T0), immediately after completion of expansion (T1), and 1 year after expansion (T2). The 3D images were superimposed and two 3D distance maps were generated to measure the midfacial soft tissue changes: immediate effects between timepoints T0 and T1 and overall effects between T0 and T2. Changes of the alar width were also measured and dental expansion was measured as the interpremolar width (IPW) on IOS. RESULTS: Twenty-nine patients (22 women, 7 men, mean age 25.9 years) were enrolled. The soft tissue in the regions of the nose, left of philtrum, right of philtrum, and upper lip tubercle demonstrated a statistically significant anterior movement of 0.30 mm, 0.93 mm, 0.74 mm, and 0.81 mm, respectively (p < 0.01) immediately after expansion (T0-T1). These changes persisted as an overall effect (T0-T2). The alar width initially increased by 1.59 mm, and then decreased by 0.08 mm after 1 year, but this effect was not significant. The IPW increased by 4.58 mm and remained stable 1 year later. There was no significant correlation between the increase in IPW and alar width (r = 0.35, p = 0.06). CONCLUSIONS: Our findings indicate that MARPE results in significant but small changes of the soft tissue in the peri-oral and nasal regions. However, the clinical importance of these findings is limited. CLINICAL RELEVANCE: MARPE is an effective treatment modality to expand the maxilla, incurring only minimal and clinically insignificant changes to the midfacial soft tissues.

The role of muscular traction in the occurrence of skeletal relapse after advancement bilateral sagittal split osteotomy (BSSO): A systematic review.

The aim of this systematic review was (i) to determine the role of muscular traction in the occurrence of skeletal relapse after advancement BSSO and (ii) to investigate the effect of advancement BSSO on the perimandibular muscles. This systematic review reports in accordance with the recommendations proposed by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Electronic database searches were performed in the databases MEDLINE, Embase and Cochrane Library. Inclusion criteria were as follows: assessment of relapse after advancement BSSO; assessment of morphological and functional change of the muscles after advancement BSSO; and clinical studies on human subjects. Exclusion criteria were as follows: surgery other than advancement BSSO; studies in which muscle activity/traction was not investigated; and case reports with a sample of five cases or fewer, review articles, meta-analyses, letters, congress abstracts or commentaries. Of the initial 1006 unique articles, 11 studies were finally included. In four studies, an intervention involving the musculature was performed with subsequent assessment of skeletal relapse. The changes in the morphological and functional properties of the muscles after BSSO were studied in seven studies. The findings of this review demonstrate that the perimandibular musculature plays a role in skeletal relapse after advancement BSSO and may serve as a target for preventive strategies to reduce this complication. However, further research is necessary to (i) develop a better understanding of the role of each muscle group, (ii) to develop new therapeutic strategies and (iii) to define criteria that allow identification of patients at risk.

Reproducibility of Manual Transfer of the Clinical Natural Head Position: Influence on the Soft Tissue and Hard Tissue Position of 3-Dimensional Virtual Surgical Planning.

PURPOSE: The purpose of this study was to assess the reproducibility of manually transferring the clinical natural head position (NHP) to the 3-dimensional (3D) virtual surgical planning and its subsequent influence on the soft tissue and maxillary hard tissue position. METHODS: A retrospective cohort study was set up. The study population consisted of subjects who underwent bimaxillary osteotomies between 2016 and 2020 at the Department of Oral and Maxillofacial Surgery in Radboud University Medical Centre (Nijmegen, the Netherlands). Cone beam computed tomography scans, dentition data, and clinical photographs were acquired 4 weeks before surgery. Two attempts (NHP1 and NHP2) were performed by a single examiner to manually transfer the NHP. 3D transformation matrices were used to quantify the transferred NHP in 3 degrees of freedom (pitch, roll, and yaw). Landmarks and surface-based matching were used to quantify the influence on the soft tissue and hard tissue positions in 6 degrees of freedom. The primary outcome variable was the reproducibility of manually aligning the NHP. The secondary and tertiary outcome variables were the effect of the reproducibility of the manually aligned NHP on the soft tissue and hard tissue displacements in the 3D virtual surgical planning. RESULTS: The study population consisted of 109 subjects: 37 males (33.9%) and 72 females (66.1%) with a mean age of 29.1 ± 10.3 years (range, 17.0 to 59.0). The manual transfer of pitch alignment (2.24 ± 1.64°; 95% confidence interval [CI], 1.93 to 2.55) was significantly less reproducible than the roll (0.56 ± 0.44°; 95% CI, 0.48 to 0.64; P < .001) and yaw (0.67 ± 0.92°; 95% CI, 0.50 to 0.85; P < .001). Subsequently, this alignment error influenced the position of the maxilla (incisal point) and soft tissue menton by 0.85 ± 0.86 mm and 1.01 ± 1.00 mm vertically and 0.78 ± 1.10 mm and 0.80 ± 1.18 mm sagittally. CONCLUSIONS: The present study demonstrated that the manual transfer of the NHP from the clinical situation to the virtual environment influenced the soft tissue and hard tissue position and that a more reproducible method of transferring the clinical NHP is recommended.

Is the pattern of mandibular asymmetry in mild craniofacial microsomia comparable to non-syndromic class II asymmetry?

OBJECTIVES: To compare the characteristics of mandibular asymmetry in patients with unilateral craniofacial microsomia (CFM) and class II asymmetry. MATERIALS AND METHODS: Pretreatment cone-beam computed tomography of consecutive adults with Pruzansky-Kaban type I and IIA CFM (CFM group) was analyzed by 3D cephalometry. Fourteen mandibular landmarks and two dental landmarks were identified. The mandibular size and positional asymmetry were calculated by using landmark-based linear and volumetric measurements, in terms of asymmetry ratios (affected/non-affected side) and absolute differences (affected - non-affected side). Results were compared with non-syndromic class II with matched severity of chin deviation (Class II group). Statistical analyses included independent t test, paired t test, chi-square test, and ANOVA. RESULTS: CFM group (n, 21; mean age, 20.4 ± 2.5 years) showed significantly larger size asymmetry in regions of mandibular body, ramus, and condyle compared to Class II group (n, 21; mean age, 27.8 ± 5.9 years) (p < 0.05). The curvature of mandibular body was asymmetric in CFM. Regarding the positional asymmetry of mandibular body, while a comparable transverse shift and a negligible yaw rotation were found among the two groups, the roll rotation in CFM was significantly greater as well as the occlusal (6.06° vs. 4.17°) and mandibular (7.84° vs. 2.80°) plane cants (p < 0.05). CONCLUSIONS: Mild CFM showed significantly more severe size asymmetry and roll rotation in mandible than non-CFM class II asymmetry. CLINICAL RELEVANCE: To improve the mandibular size and positional asymmetry in CFM, adjunct hard tissue augmentation or reduction in addition to OGS orthodontics with a meticulous roll and yaw planning is compulsory, which is expected to be distinct from treating non-CFM class II asymmetry.

Efficacy of Miniscrew-Assisted Rapid Palatal Expansion (MARPE) in late adolescents and adults with the Dutch Maxillary Expansion Device: a prospective clinical cohort study.

OBJECTIVES: To provide a higher degree of evidence on the efficacy of Miniscrew-Assisted Rapid Palatal Expansion (MARPE) in late adolescents and adults, thereby applying the Dutch Maxillary Expansion Device (D-MED). MATERIALS AND METHODS: D-MED was developed as an individualized, 3D-designed, and fabricated MARPE appliance supported by 4 palatal miniscrews. Patients from the age of 16 onwards with transverse maxillary deficiency were enrolled consecutively. Pre-expansion and immediate post-expansion CBCTs and intra-oral scans were acquired and measurements of skeletal, alveolar, and dental expansion as well as dental and periodontal side-effects were performed. RESULTS: Thirty-four patients were enrolled (8 men, 26 women) with mean age 27.0 ± 9.4 years. A success rate of 94.1% was achieved (32/34 patients). The mean expansion duration, or mean observation time, was 31.7 ± 8.0 days. The mean expansion at the maxillary first molars (M1) and first premolars (P1) was 6.56 ± 1.70 mm and 4.19 ± 1.29 mm, respectively. The expansion was 60.4 ± 20.1% skeletal, 8.1 ± 27.6% alveolar, and 31.6 ± 20.1% dental at M1 and 92.2 ± 14.5% skeletal, 0.0 ± 18.6% alveolar, and 7.8 ± 17.7% dental at P1, which was both statistically (p < 0.001) and clinically significant. Buccal dental tipping (3.88 ± 3.92° M1; 2.29 ± 3.89° P1), clinical crown height increase (0.12 ± 0.31 mm M1; 0.04 ± 0.22 mm P1), and buccal bone thinning (- 0.31 ± 0.49 mm M1; - 0.01 ± 0.45 mm P1) were observed, while root resorption could not be evaluated. CONCLUSIONS: MARPE by application of D-MED manifested its efficacy in a prospective clinical setting, delivering a high amount of skeletal expansion with limited side-effects in late adolescents and adults. CLINICAL RELEVANCE: Higher quality evidence is supportive of MARPE as a safe and successful non-surgical treatment option for transverse maxillary deficiency.

What is the Oral Health-related Quality of Life following Miniscrew-Assisted Rapid Palatal Expansion (MARPE)? A prospective clinical cohort study.

BACKGROUND: Miniscrew-Assisted Rapid Palatal Expansion (MARPE) is a non-surgical orthodontic treatment for transverse maxillary deficiency. This study aimed to investigate the Oral Health-related Quality of Life (OHRQoL) and pain perception of patients undergoing MARPE treatment. METHODS: 42 consecutive patients (9 men, 33 women) from the age of 16 onwards (mean: 27.4 ± 9.3 years; range 17.1-55.7 years) who received a MARPE treatment were included. OHRQoL was assessed with the short form of the Oral Health Impact Profile (OHIP-14) questionnaire. Patients filled out the questionnaire at baseline (T0) and weekly during the expansion phase (P1) and in the post-expansion phase (P2). Pain intensity was assessed with a Visual Analogue Scale (VAS) questionnaire and filled out daily during expansion, along with a question on the intake of analgesics. The mean weekly and total OHIP-score and OHIP-score per domain were calculated at T0, P1 and P2, as well as mean weekly and total VAS-scores for average pain, maximum pain and analgesics intake during P1. Kruskal-Wallis tests were used to test for differences in OHIP between T0, P1 and P2. The level of significance was set at 0.05. RESULTS: The mean OHIP-score was 10.86 ± 9.71 at T0 and increased to 17.18 ± 10.43 during P1 (p < 0.001), after which it returned to pre-expansion levels, 9.27 ± 7.92 (p = 0.907) during P2. At the domain level, there was a statistically significant increase in OHIP-score at P1 for functional limitation, physical pain, psychological discomfort and social disability. The mean VAS-score for average pain during expansion was 16.00 ± 19.73 mm. Both OHIP-score (25.00 ± 10.25), average pain (33.72 ± 16.88 mm), maximum pain (44.47 ± 17.99 mm) and analgesics intake (59%) were highest at initiation of the expansion and decreased by the end of expansion. CONCLUSIONS: MARPE is a generally well-tolerated expansion treatment. A temporary decline in OHRQoL and moderate pain are present at the start of expansion, followed by a recovery of OHRQoL and very mild pain during the rest of treatment. Clinicians should be aware of the effects of MARPE on patients' quality of life and manage the expected discomfort and impediments with adequate communication and patient education.

Three-Dimensional Analysis of the Condylar Hypoplasia and Facial Asymmetry in Craniofacial Microsomia Using Cone-Beam Computed Tomography.

PURPOSE: To assess the condylar hypoplasia and its correlation with craniofacial deformities in adults with unilateral craniofacial microsomia (CFM). METHODS: Pretreatment cone-beam computed tomography scans of consecutive adults (mean age: 20.4 ± 3.0 years; range: 17.3 to 31.4 years) with Pruzansky-Kaban type I and IIA CFM were reconstructed in 3D. Both condyles were segmented. Asymmetry ratios (affected side/contralateral side) of condylar volume were calculated to indicate the extent of condylar hypoplasia. 3D cephalometry was performed to quantify the maxillomandibular morphology and facial asymmetry. The correlations in between were assessed by using Pearson's or Spearman's correlation coefficients. RESULTS: Thirty-six subjects were enrolled, consisting of 22 subjects with Pruzansky-Kaban type I and 14 subjects with type IIA. The condyles in type IIA group were significantly more hypoplastic in height (asymmetry ratio: 40.69 vs 59.95%, P = .006) and volume (18.16 vs 47.84%, P < .001) compared to type I group. Type IIA group had a significantly smaller SNB value than type I group (72.94° vs 77.41°, P = .012), and a significantly greater facial asymmetry (P < .05). The hypoplastic extent of condylar volume and Pruzansky-Kaban types were significantly correlated with SNB (r = 0.457 and ρ = -0.411, respectively), upper incisor deviation (r = -0.446 and ρ = 0.362), chin deviation (r = -0.477 and ρ = 0.527), upper occlusal plane cant (r = -0.672 and ρ = 0.631), and mandibular plane cant (r = -0.557 and ρ = 0.357, P < .05). CONCLUSION: For unilateral CFM adults, greater condylar hypoplasia in volume along with more severe mandibular retrusion and facial asymmetry objectively indicated a higher scale of Pruzansky-Kaban classification (type IIA). These quantitative distinctions are expected to enhance the diagnostic reliability of CFM.

Efficacy of Miniscrew-Assisted Rapid Palatal Expansion (MARPE) in late adolescents and adults: a systematic review and meta-analysis.

BACKGROUND: Miniscrew-Assisted Rapid Palatal Expansion (MARPE) is a non-surgical treatment for transverse maxillary deficiency. However, there is limited evidence concerning its efficacy. OBJECTIVES: This systematic review aims to evaluate the efficacy of MARPE in late adolescents and adults by assessing success rate and skeletal and dental transverse maxillary expansion, as well as treatment duration, dental and periodontal side effects and soft tissue effects. SEARCH METHODS: Seven electronic databases were searched (MEDLINE, Embase, Cochrane Library, Web of Science, Scopus, ProQuest and ClinicalTrials.gov) without limitations in November 2020. SELECTION CRITERIA: Randomized and non-randomized clinical trials and observational studies on patients from the age of 16 onwards with transverse maxillary deficiency who were treated with MARPE and which included any of the predefined outcomes. DATA COLLECTION AND ANALYSIS: Inclusion eligibility screening, data extraction and risk of bias assessment were performed independently in duplicate. When possible, exploratory meta-analyses of mean differences (MDs) with their 95% confidence intervals (CIs) were conducted, followed by the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) analysis of the evidence quality. RESULTS: Eight articles were included: two prospective and six retrospective observational studies. One study had a moderate risk of bias, whereas seven studies had a serious risk of bias. GRADE quality of evidence was very low. MARPE showed a high success rate (mean: 92.5%; 95%CI: 88.7%-96.3%), resulting in a significant skeletal width increase (MD: 2.33 mm; 95%CI: 1.63 mm-3.03 mm) and dental intermolar width increase (MD: 6.55 mm; 95%CI: 5.50 mm-7.59 mm). A significant increase in dental tipping, a decrease in mean buccal bone thickness and buccal alveolar height, as well as nasal soft tissue change was present (P < 0.05). The mean duration of expansion ranged from 20 to 126 days. LIMITATIONS: One of the main drawbacks was the lack of high-quality prospective studies in the literature. CONCLUSIONS AND IMPLICATIONS: MARPE is a treatment modality that is associated with a high success rate in skeletal and dental maxillary expansion. MARPE can induce dental and periodontal side effects and affect peri-oral soft tissues. Given the serious risk of bias of the included studies, careful data interpretation is necessary and future research of higher quality is strongly recommended. REGISTRATION: PROSPERO (CRD42020176618). FUNDING: No grants or any other support funding were received.

Median Lingual Foramen, a new midmandibular cephalometric landmark.

PURPOSE: In asymmetrical mandibles, it is often challenging to identify the mandibular midline. The median lingual foramen (MLF) is located at the midline of the anterior mandible. The purpose of this study is to evaluate the reproducibility of identifying the MLF compared to conventional landmarks on cone beam computed tomography's (CBCT's) to mark the mandibular midline. MATERIAL AND METHODS: Ten symmetrical class II, 10 symmetrical class III, ten asymmetrical class II and 10 asymmetrical class III patients were included. On CBCTs, the cephalometric landmarks menton, pogonion, genial tubercle and MLF were identified twice by two observers. RESULTS: A high intra- and interobserver reproducibility was found for all landmarks, the highest being the MLF. The gain in accuracy is 0.998 mm, 0.824 mm and 0.361 mm compared to pogonion, genial tubercle and menton, respectively (P-value <.05). CONCLUSION: MLF is a reliable and reproducible landmark to indicate the midline of the mandible, particularly in Class II asymmetric mandibles.

Landmark-Based Versus Voxel-Based 3-Dimensional Quantitative Analysis of Bimaxillary Osteotomies: A Comparative Study.

PURPOSE: We compared the accuracy of landmark-based and voxel-based 3-dimensional (3D) analysis to quantify the osseous movements of the maxilla and mandible after bimaxillary osteotomy. MATERIALS AND METHODS: Cone beam computed tomography (CBCT) scans of 15 patients who had undergone bimaxillary osteotomy were randomly selected from the database. Before surgery, CBCT scanning was performed and an individualized 3D virtual surgical plan made for all patients. During surgery, the mandibular and maxillary segments were positioned as planned using 3D-milled interocclusal splints. At 1 week after surgery, a postoperative CBCT scan was acquired. All pre- and postoperative CBCT data were rendered in 3 dimensions. The 3D virtual head models were superimposed on the cranial base. The 3D surgical movements of the maxilla and mandible were quantified using conventional landmark-based 3D cephalometric analyses and voxel-based 3D analyses (OrthoGnathicAnalyser). This process was performed by the same observer 3 times. The intraclass correlations and Bland-Altman plots were computed to quantify the measurement errors and reproducibility of both methods. RESULTS: High intraclass correlation coefficients were found for both methods. The voxel-based analyses yielded a higher correlation concerning the maxilla and distal mandible (r = 0.98) compared with the landmark-based cephalometric analyses (r = 0.90). CONCLUSIONS: The use of voxel-based 3D analyses in the quantification of osseous movements was more reliable and reproducible than the use of conventional landmark-based 3D analyses.

Integration of digital dental casts in cone beam computed tomography scans-a clinical validation study.

OBJECTIVES: Images derived from cone beam computed tomography (CBCT) scans lack detailed information on the dentition and interocclusal relationships needed for proper surgical planning and production of surgical splints. To get a proper representation of the dentition, integration of a digital dental model into the CBCT scan is necessary. The aim of this study was to validate a simplified protocol to integrate digital dental models into CBCT scans using only one scan. MATERIALS AND METHODS: Conventional protocol A used one combined upper and lower impression and two CBCT scans. The new protocol B included placement of ten markers on the gingiva, one CBCT scan, and two separate impressions of the upper and lower dentition. Twenty consecutive patients, scheduled for mandibular advancement surgery, were included. To validate protocol B, 3-dimensional reconstructions were made, which were compared by calculating the mean intersurface distances obtained with both protocols. RESULTS: The mean distance for all patients for the upper jaw is 0.39 mm and for the lower jaw is 0.30 mm. For ten out of 20 patients, all distances were less than 1 mm. For the other ten patients, all distances were less than 2 mm. CONCLUSIONS: Mean distances of 0.39 and 0.30 mm are clinically acceptable and comparable to other studies; therefore, this new protocol is clinically accurate. CLINICAL RELEVANCE: This new protocol seems to be clinically accurate. It is less time consuming, gives less radiation exposure for the patient, and has a lower risk for positional errors of the impressions compared to other integration protocols.

Validation of 3D documentation of palatal soft tissue shape, color, and irregularity with intraoral scanning.

OBJECTIVES: The purpose of this study was to assess the feasibility of 3D intraoral scanning for documentation of palatal soft tissue by evaluating the accuracy of shape, color, and curvature. MATERIALS AND METHODS: Intraoral scans of ten participants' upper dentition and palate were acquired with the TRIOS® 3D intraoral scanner by two observers. Conventional impressions were taken and digitized as a gold standard. The resulting surface models were aligned using an Iterative Closest Point approach. The absolute distance measurements between the intraoral models and the digitized impression were used to quantify the trueness and precision of intraoral scanning. The mean color of the palatal soft tissue was extracted in HSV (hue, saturation, value) format to establish the color precision. Finally, the mean curvature of the surface models was calculated and used for surface irregularity. RESULTS: Mean average distance error between the conventional impression models and the intraoral models was 0.02 ± 0.07 mm (p = 0.30). Mean interobserver color difference was - 0.08 ± 1.49° (p = 0.864), 0.28 ± 0.78% (p = 0.286), and 0.30 ± 1.14% (p = 0.426) for respectively hue, saturation, and value. The interobserver differences for overall and maximum surface irregularity were 0.01 ± 0.03 and 0.00 ± 0.05 mm. CONCLUSIONS: This study supports the hypothesis that the intraoral scan can perform a 3D documentation of palatal soft tissue in terms of shape, color, and curvature. CLINICAL RELEVANCE: An intraoral scanner can be an objective tool, adjunctive to the clinical examination of the palatal tissue.

Placement of an antibiotic oral pack on the hard palate after primary cleft palatoplasty: a randomized controlled trial into the effect on fistula rates.

OBJECTIVE: The objective of this study is to determine whether placement of an antibiotic oral pack on the hard palate reduces fistula rates after primary cleft palatoplasty. SUBJECTS AND METHODS: This study was a parallel blocked randomized controlled trial. The study consisted of two groups of 100 patients each with non-syndromic unilateral complete cleft lip, alveolus, and hard and soft palate that underwent primary palatoplasty. Group A had an oral pack placed on the hard palate for 5 days postoperatively while group B did not. Occurrence of fistulae between both groups was tested using odds ratios (OR). RESULTS: In 2% of the patients in group A, a fistula was found 6 months after palatal surgery. In contrast, in 21% of the patients in group B, a palatal fistula could be confirmed. The fistula occurrence in group A was statistically significantly lower than that in group B (OR = 0.0768, CI = [0.02 … 0.34], p < 0.001). CONCLUSION: The findings of this study provide evidence that the rate of fistula formation after primary palatoplasty is significantly reduced if a pack soaked with antibiotic cream is placed on the palate postoperatively for 5 days. CLINICAL RELEVANCE: The use of an antibiotic pack after cleft palate repair can be recommended to prevent occurrence of oronasal fistulae.

Novel mutations in LRP6 highlight the role of WNT signaling in tooth agenesis.

PURPOSE: We aimed to identify a novel genetic cause of tooth agenesis (TA) and/or orofacial clefting (OFC) by combining whole-exome sequencing (WES) and targeted resequencing in a large cohort of TA and OFC patients. METHODS: WES was performed in two unrelated patients: one with severe TA and OFC and another with severe TA only. After deleterious mutations were identified in a gene encoding low-density lipoprotein receptor-related protein 6 (LRP6), all its exons were resequenced with molecular inversion probes in 67 patients with TA, 1,072 patients with OFC, and 706 controls. RESULTS: We identified a frameshift (c.4594delG, p.Cys1532fs) and a canonical splice-site mutation (c.3398-2A>C, p.?) in LRP6, respectively, in the patient with TA and OFC and in the patient with severe TA only. The targeted resequencing showed significant enrichment of unique LRP6 variants in TA patients but not in nonsyndromic OFC patients. Of the five variants in patients with TA, two affected the canonical splice site and three were missense variants; all variants segregated with the dominant phenotype, and in one case the missense mutation occurred de novo. CONCLUSION: Mutations in LRP6 cause TA in humans.Genet Med 18 11, 1158-1162.

Does powdering of the dentition increase the accuracy of fusing 3D stereophotographs and digital dental casts.

OBJECTIVES: The shiny vestibular surfaces of teeth make it difficult to match digital dental casts to 3D stereophotogrammetric images of patient teeth. This study tested whether reducing this shininess by coating the teeth with titanium-oxide powder might improve the accuracy of the matching procedure. METHODS: Twenty patients participated in the study. For each patient, 3D stereophotogrammetric images were taken without and with a powder coating. Separately, digital dental casts were created. Next, the digital dental casts were fused with the 3D stereophotogrammetric images of either non-powdered or powdered dentition. Distance maps were created to evaluate the inter-surface distance between the digital dental cast and the 3D images. The matching accuracy was compared for dentition with and without powdering. RESULTS: Of all recorded distances between corresponding points, 95% was smaller than 0.84mm for the powdered dentition and smaller than 0.90mm for the non-powdered dentition. Although powdered dentition showed significantly better matching than non-powdered dentition, the difference was less than 0.1mm. Intra-observer statistics showed that five out of 24 repetitions gave significantly different results, but only for dentition that was not powdered. LIMITATIONS: The patients did not have any major malocclusions. Severe malocclusions might cause greater difficulty in matching the dentition without powder. Only one type of powder was used, but it effectively reduced shininess. CONCLUSION: Powdering the dentition had a small, but significant, positive effect on matching. However, this effect was of minor clinical importance. Therefore, we do not recommend powdering the dentition for 3D stereophotogrammetric images used for matching procedures.

Three-dimensional facial simulation in bilateral sagittal split osteotomy: a validation study of 100 patients.

PURPOSE: Three-dimensional (3D) virtual planning of orthognathic surgery in combination with 3D soft tissue simulation allows the surgeon and the patient to assess the 3D soft tissue simulation. This study was conducted to validate the predictability of the mass tensor model soft tissue simulation algorithm combined with cone-beam computed tomographic (CBCT) imaging for patients who underwent mandibular advancement using a bilateral sagittal split osteotomy (BSSO). MATERIALS AND METHODS: One hundred patients were treated with a BSSO according to the Hunsuck modification. The pre- and postoperative CBCT scans were matched and the mandible was segmented and aligned. The 3D distance maps and 3D cephalometric analyses were used to calculate the differences between the soft tissue simulation and the actual postoperative results. Other study variables were age, gender, and amount of mandibular advancement or rotation. RESULTS: For the entire face, the mean absolute error was 0.9 ± 0.3 mm, the mean absolute 90th percentile was 1.9 mm, and for all 100 patients the absolute mean error was less than or equal to 2 mm. The subarea with the least accuracy was the lower lip area, with a mean absolute error of 1.2 ± 0.5 mm. No correlation could be found between the error of prediction and the amount of advancement or rotation of the mandible or age or gender of the patient. CONCLUSION: Overall, the soft tissue prediction algorithm combined with CBCT imaging is an accurate model for predicting soft tissue changes after mandibular advancement. Future studies will focus on validating the mass tensor model soft tissue algorithm for bimaxillary surgery.

Regional facial asymmetries in unilateral orofacial clefts.

OBJECTIVES: Assess facial asymmetry in subjects with unilateral cleft lip (UCL), unilateral cleft lip and alveolus (UCLA), and unilateral cleft lip, alveolus, and palate (UCLP), and to evaluate which area of the face is most asymmetrical. METHODS: Standardized three-dimensional facial images of 58 patients (9 UCL, 21 UCLA, and 28 UCLP; age range: 8.6-12.3 years) and 121 controls (age range 9-12 years) were mirrored and distance maps were created. Absolute mean asymmetry values were calculated for the whole face, cheek, nose, lips, and chin. One-way analysis of variance, Kruskal-Wallis, and t-test were used to assess the differences between clefts and controls for the whole face and separate areas. RESULTS: Clefts and controls differ significantly for the whole face as well as in all areas. Asymmetry is distributed differently over the face for all groups. In UCLA, the nose was significantly more asymmetric compared with chin and cheek (P = 0.038 and 0.024, respectively). For UCL, significant differences in asymmetry between nose and chin and chin and cheek were present (P = 0.038 and 0.046, respectively). In the control group, the chin was the most asymmetric area compared to lip and nose (P = 0.002 and P = 0.001, respectively) followed by the nose (P = 0.004). In UCLP, the nose, followed by the lips, was the most asymmetric area compared to chin, cheek (P < 0.001 and P = 0.016, respectively). LIMITATIONS: Despite division into regional areas, the method may still exclude or underrate smaller local areas in the face, which are better visualized in a facial colour coded distance map than quantified by distance numbers. The UCL subsample is small. CONCLUSION: Each type of cleft has its own distinct asymmetry pattern. Children with unilateral clefts show more facial asymmetry than children without clefts.

Secondary closure of small- to medium-size palatal defects after ablative surgery: reappraisal of reconstructive techniques.

PURPOSE: Postoncologic reconstruction of the palate represents a major surgical challenge with respect to the thin intraoral and intranasal lining. Current reconstructive methods have ranged from obturative closure of the defect to microsurgical free tissue transfer. The final choice of treatment will be influenced by the size and location of the defect and surgeon experience. The goals of palate repair include optimizing palatal function for speech and eating, and avoiding dehiscence or postoperative fistulas. This study assessed the reliability of locoregional flaps for reconstructing maxillary defects. PATIENTS AND METHODS: The present study described the surgical outcome of locoregional reconstruction of the hard and soft palate of 5 patients who had previously undergone tumor ablative surgery. They ranged in age from 19 to 64 years. None had received postoperative radiotherapy. The resultant surgical defects ranged in size from 2.5 to 12 cm(2). One patient experienced velopharyngeal insufficiency. RESULTS: In all cases, the palate was closed at the first attempt without complications. All flaps survived, and complete closure was obtained in these 4 patients. The patient with the velopharyngeal insufficiency experienced a significant improvement in articulation and swallowing function. CONCLUSIONS: The results of these 5 cases indicate that secondary locoregional flaps are a suitable alternative for palatal defect management. They have a high success rate and functional outcome. These secondary techniques can be reliably used to reconstruct small- to moderate-size palatal defects and represent a reliable reconstructive option with minimal morbidity.