The Ability to Sustain Facial Expressions.

To gain more insight into facial muscle function, imaging during action would be optimal. Magnetic resonance imaging is highly suitable for visualizing facial muscles. However, magnetic resonance imaging requires the individual to remain as still as possible for a while. Knowledge of the ability to sustain facial expressions is requisite before scanning individuals. This could help adapting the scanning protocol to obtain optimal quality of imaging the muscles in action. A study, including 10 healthy volunteers, was done to perceive the extent of movement while holding facial expressions of smiling and pouting. During 6 minutes, 3-dimensional photographs were taken every consecutive minute while the participants maintained their facial expressions as motionless as possible. The movement was objectified by creating distance maps between the 2 models and calculating the Root Mean Square using the software 3DMedX. The results showed that most movements occurred in the first minute, with a decrease of the intensity of the expression. After the first minute, the expression, although less intense, could be held stable. This implies that magnetic resonance imaging scanning during facial expression is possible, provided that the scanning starts after the first minute has elapsed. In addition, results demonstrated that more slackening of the muscles while smiling compared with pouting.

Reliability of mandibular range of motion measurements in healthy children.

BACKGROUND: Mandibular range of motion (MROM) variables are widely used to evaluate oral function. OBJECTIVE: The aim of this study was to establish the reliability of MROM variables in healthy children. METHODS: In this cross-sectional study, healthy children were examined 2 weeks apart. The following MROM variables were established: active maximum interincisal opening (AMIO), passive maximum interincisal opening (PMIO), protrusion and left and right laterotrusion. The reliability of the MROM measurements was determined by analysing the intra-class correlation coefficient (ICC), standard error of measurement (SEM), smallest detectable change (SDC) and limits of agreement (LoA). RESULTS: A total of 167 healthy children were examined. The ICC indicated good reliability for AMIO (0.885); excellent reliability for PMIO (0.925); and moderate reliability for protrusion (0.578), laterotrusion left (0.601) and laterotrusion right (0.634). The SDC was 0.9 mm for AMIO, 0.4 mm for PMIO, 2.2 mm for protrusion, 1.6 mm for laterotrusion left and 1.4 mm for laterotrusion right. The LoA was -5.67 to 5.82 for AMIO, -3.90 to 3.57 for PMIO, -3.89 to 3.55 for protrusion, -2.99 to 2.77 for laterotrusion left, and - 2.71 to 2.77 for laterotrusion right. CONCLUSIONS: AMIO and PMIO measurements are both highly reliable in healthy children. The low SDC indicate that AMIO and PMIO are promising longitudinal measurements. Protrusion and laterotrusion measurements had moderate reliability. These results support our clinical recommendation to measure AMIO rather than PMIO, as PMIO is more difficult and more time-consuming to perform than AMIO.

Osteoinductive calcium phosphate with submicron topography as bone graft substitute for maxillary sinus floor augmentation: A translational study.

OBJECTIVES: The aim of this study was the preclinical and clinical evaluation of osteoinductive calcium phosphate with submicron surface topography as a bone graft substitute for maxillary sinus floor augmentation (MSFA). MATERIAL AND METHODS: A preclinical sheep model of MSFA was used to compare a calcium phosphate with submicron needle-shaped topography (BCPN , MagnetOs Granules, Kuros Biosciences BV) to a calcium phosphate with submicron grain-shaped topography (BCPG ) and autologous bone graft (ABG) as controls. Secondly, a 10-patient, prospective, randomized, controlled trial was performed to compare BCPN to ABG in MSFA with two-stage implant placement. RESULTS: The pre-clinical study demonstrated that both BCPN and BCPG were highly biocompatible, supported bony ingrowth with direct bone apposition against the material, and exhibited bone formation as early as 3 weeks post-implantation. However, BCPN demonstrated significantly more bone formation than BCPG at the study endpoint of 12 weeks. Only BCPN reached an equivalent amount of bone formation in the available space and a greater proportion of calcified material (bone + graft material) in the maxillary sinus compared to the "gold standard" ABG after 12 weeks. These results were validated in a small prospective clinical study, in which BCPN was found comparable to ABG in implant stability, bone height, new bone formation in trephine core biopsies, and overall clinical outcome. CONCLUSION: This translational work demonstrates that osteoinductive calcium phosphates are promising bone graft substitutes for MSFA, whereas their bone-forming potential depends on the design of their surface features. Netherlands Trial Register, NL6436.

Gastrointestinal symptoms in patients with isolated oligodontia and a Wnt gene mutation.

OBJECTIVE: Since Wnt signaling plays an important role in both tooth agenesis and altered intestine homeostasis, the aim was to compare gastrointestinal symptoms in patients with isolated oligodontia caused by a Wnt pathway gene mutation and controls. METHODS: A case-control study was designed to compare self-reported gastrointestinal symptoms among patients with isolated oligodontia, caused by a Wnt signaling gene mutation, and fully dentate controls. The Gastrointestinal Symptom Rating Scale (GSRS) was used to assess gastrointestinal symptoms. Prevalence and severity of gastrointestinal symptoms among patients and age- and gender-matched controls were evaluated. RESULTS: Twenty patients with isolated oligodontia and a pathogenic variant in the wnt pathway genes WNT10A, LRP6, or PAX9 participated. The prevalence of gastrointestinal symptoms was higher in the oligodontia patients compared to their controls (Χ2 (1) = 87.33, p = .008). Mean GSRS total scores (p = .011) and domain scores for "abdominal pain" (p = .022), "reflux" (p = .003) and constipation (p = .030) were higher for these oligodontia patients compared to their controls. CONCLUSION: Gastrointestinal symptoms are more prevalent and more severe in patients with isolated oligodontia and a deficiency in a Wnt pathway-related gene, when compared to controls without tooth agenesis.

Oral functioning after open versus closed treatment of unilateral condylar neck or base fractures: A two-centre controlled clinical trial.

BACKGROUND: Oral functioning and rehabilitation in patients after condylar trauma can be measured by objective functional outcomes and patient-reported outcomes. The similarities or differences between these outcomes may contribute to the decision if open treatment (OT) or closed treatment (CT) will obtain the most advantageous results. OBJECTIVES: The aim of this study was to compare OT versus CT for unilateral condylar mandibular neck or base fractures in a two-centre controlled clinical trial by objective functional outcomes and patient-reported outcomes measured at 6 weeks and 6 months follow-up. Additionally, these outcomes were compared within each group. METHODS: Patients were enrolled between January 2017 and November 2019. In one centre, patients received OT by extra-oral open reduction and internal fixation. In another centre, patients received CT by maxillomandibular fixation. Objective measurements included the mixing ability test (MAT) and mandibular active range of motion (ROM). Patient-reported outcomes included the mandibular function impairment questionnaire (MFIQ) and visual analogue scale (VAS) for pain. Independent t-tests and Mann-Whitney U-tests were used to determine differences between the treatment groups at 6 weeks and 6 months follow-up. Paired t-tests and Wilcoxon signed rank tests were used to determine differences within each group. RESULTS: Thirty-three patients were enrolled. No differences were found between the groups treated with OT or CT for MAT, ROM, MFIQ and VAS. Both groups showed functional improvement. CONCLUSION: Good objective functional outcomes and patient-reported outcomes were achieved with both OT and CT in patients with unilateral condylar mandibular neck or base fractures.

A Novel and Practical Protocol for Three-Dimensional Assessment of Alveolar Cleft Grafting Procedures.

OBJECTIVE: To evaluate the reproducibility and accuracy of a new, easy-to-use volumetric assessment of the alveolar cleft. DESIGN: Twelve cone-beam computed tomography (CBCT) datasets of patients with a unilateral cleft lip, alveolus, and palate were evaluated by two investigators. Residual alveolar cleft calcified volume one year after surgery was analyzed by using standardized landmarks to determine the borders of the cleft defect and semi-automatically segment the alveolar cleft defect. RESULTS: The Dice-coefficient between observers for the segmented preoperative alveolar cleft defect was 0.81. Average percentage of residual alveolar cleft calcified material was 66.7% one year postoperatively. CONCLUSIONS: This study demonstrates a reliable and practical semi-automatic three-dimensional volumetric assessment method for unilateral clefts using CBCT.

Growth curves for mandibular range of motion and maximum voluntary bite force in healthy children.

Mandibular range of motion and bite force are indispensable variables for the evaluation of mandibular function. There are a variety of medical and dental conditions that can negatively affect mandibular function. Values for mandibular range of motion (i.e., active and passive maximum interincisal mouth opening, protrusion, and laterotrusion) and anterior maximum voluntary bite force (AMVBF) in healthy children and adolescents can help in recognizing temporomandibular dysfunction. In this longitudinal study, 169 healthy children aged 6-18 years were included. They were examined at four time points over 1 year. Mixed model analysis was performed to produce growth curves of mandibular range of motion and AMVBF. Average active maximum interincisal mouth opening was significantly higher in boys with 50.0 mm compared to 47.8 mm in girls. Boys also had a significantly higher AMVBF than girls with an average of 169.0 N versus 140.0 N, respectively. Growth curves of active and passive maximum interincisal mouth opening showed an increase with age, albeit levelling off through puberty. The growth curves of AMVBF in girls reach a plateau phase at ages 12-14 years, after which the curve descends; in boys, the AMVBF tended to increase up to 18 years of age, although a slow-down after 14 years of age was noted.

Maximum bite force in children with juvenile idiopathic arthritis with and without clinical established temporomandibular joint involvement and in healthy children: a cross-sectional study.

BACKGROUND: In children with juvenile idiopathic arthritis (JIA), the temporomandibular joint (TMJ) can be involved, resulting in dysfunction of the masticatory system. Bite force is one of the variables that reflects the function of the masticatory system. The aim of this study was to compare maximum bite force in children with JIA, with and without TMJ involvement and with healthy children. METHODS: Children with JIA and healthy children between the ages 6 and 18 were included in this cross-sectional study. The clinical examination consisted of measuring the anterior maximum voluntary bite force (AMVBF), assessment of the TMJ screening protocol items and TMJ, masseter and temporal muscle palpation pain. Unadjusted linear regression analyses were performed to evaluate the explanatory factors for AMVBF. Two adjusted models were constructed with corrections for age and gender differences: model 1 to compare children with JIA and healthy children and model 2 to compare children with JIA with and without TMJ involvement. RESULTS: In this cross-sectional study, 298 children with JIA and 169 healthy children participated. AMVBF was 24 Newton (N) lower in children with JIA, when compared with healthy children (95%CI: -35.5--12.4, p = .000). When children with JIA also had clinically established TMJ involvement, AMVBF was reduced 42 N (component JIA:-16.78, 95% CI -28.96--4.59, p = .007 and component TMJ involvement:-25.36, 95% CI -40.08--10.63, p = .001). Age and male gender increased AMVBF. CONCLUSION: Children with JIA had a reduction in the AMVBF compared with healthy children. In children with JIA and clinically established TMJ involvement, AMVBF was more reduced.

Locoregional recurrence rate and disease-specific survival following marginal vs segmental resection for oral squamous cell carcinoma with mandibular bone invasion.

BACKGROUND AND OBJECTIVES: To determine locoregional recurrence rate (LRR) and disease-specific survival (DSS) following marginal vs segmental mandibulectomy. METHODS: Included were 210 patients, who had marginal or segmental mandibulectomy between 2000 and 2017. Marginal resection was performed when complete removal of the tumor was deemed feasible on the condition that at least 1 cm bone height of the inferior border of the mandible could be preserved. Segmental resection was performed in case less than 1 cm bone height of the mandible would remain. Clinical and histopathological data were collected from medical records. LRR and DSS were computed using Kaplan-Meier analysis. Cox-regression analysis was used to identify risk factors for LRR and DSS. RESULTS: A total of 59 marginal and 151 segmental resections had been performed. There was no significant difference in 3- and 5-year LRR (P = .904) and no significant difference in 3- and 5-year DSS (P = .362) between the marginal and segmental resection group. Cox-regression analysis showed a trend for surgical margin less than equal to 1 mm, to affect LRR (P = .05) and surgical margin less than equal 1 mm, perineural invasion and lymph node metastasis to affect DSS (P < .05). CONCLUSIONS: There was no difference in outcome between the two types of mandibulectomy.

Tongue function and its influence on masticatory performance in patients treated for oral cancer: a five-year prospective study.

PURPOSE: The purpose of this study was to observe the impact of oral oncological treatment, including the recovery of several tongue functions (force, mobility, and sensory functions), and to determine the influence of these functions on masticatory performance. MATERIALS AND METHODS: Masticatory performance and tongue force, mobility, and sensory functions were determined in 123 patients with oral cavity cancer. The assessments were performed 4 weeks before treatment and 4 to 6 weeks, 6 months, 1 year, and 5 years after treatment. Generalized estimation equations and mixed model analyses were performed, correcting for previously identified factors in the same population. RESULTS: A significant deterioration in tongue mobility and sensory function was observed in patients with mandible and tongue and/or floor-of-mouth tumors. Better tongue force and sensory function (thermal and tactile) positively influenced masticatory performance, and this effect was stronger where fewer occlusal units were present. The effect of both the tongue force and maximum bite force was weaker in dentate patients in comparison with patients with full dentures. A web-based application was developed to enable readers to explore our results and provide insight into the coherence between the found factors in the mixed model. CONCLUSIONS: Tongue function deteriorates after oral oncological treatment, without statistically significant recovery. Adequate bite and tongue forces are especially important for patients with a poor prosthetic state. Patients with sensory tongue function deficits especially benefit from the presence of more occluding pairs.

Incidence of complications in secondary alveolar bone grafting of bilateral clefts with premaxillary osteotomy: a retrospective cohort study.

OBJECTIVE: To evaluate factors affecting incidence of complications after secondary alveolar bone grafting with premaxillary osteotomy (SABG + PO) in children with complete bilateral cleft of lip and palate (BCLP). MATERIALS AND METHODS: Data were collected from children with BCLP treated with SABG + PO from 2004 to 2014 at our institute. Preoperative parameters included age, donor site, race, gingival health, bone quality around cleft-related teeth, premaxilla position, graft timing, presence of canines in the cleft, and presence of deciduous teeth around the cleft area. Logistic regression and the chi-squared test were used to assess correlations and the incidence of complications. RESULTS: In the 64 patients, a significant correlation was found between complication rate and timing of bone grafting with respect to early versus late SABG + PO (p = 0.041), age > 12 years (p = 0.011; odds ratio (OR) 5.9; 95% confidence interval (CI) 1.49-23.93), malposition of the premaxilla (p = 0.042; OR 3.3; 95% CI 1.04-10.13), and preoperative bone quality around cleft-related teeth (p = 0.005; OR 5.3; 95% CI 1.6-17.2). CONCLUSIONS: The timing of SABG + PO is essential, as early SABG + PO is associated with fewer complications. A malpositioned premaxilla and poor bone quality around cleft-related teeth are associated with more complications. Therefore, preoperative orthodontic repositioning of the malpositioned premaxilla before SABG + PO should be considered. CLINICAL RELEVANCE: Analysis of treatment protocols and complications for BCLP patients underscores that proper timing of SABG + PO and correct premaxilla repositioning help reduce complications.

Reproducibility and construct validity of the utrecht mixing ability Test to obtain masticatory performance outcome in patients with condylar mandibular fractures.

OBJECTIVE: This study assessed the test-retest reproducibility of the Utrecht mixing ability test (MAT) and the construct validity of the MAT in relation to the Mandibular Function Impairment Questionnaire (MFIQ) in patients with mandibular condylar fractures. MATERIAL AND METHODS: Twenty-six patients treated for a mandibular condylar fracture participated in this clinimetric study; all patients performed the MAT twice. Simultaneously the MFIQ was conducted. Test-retest reliability and construct validity were assessed using the intra-class correlation coefficient (ICC) and Spearman correlation, respectively. RESULTS: The ICC of the MAT was 0.906 (95% CI: 0.801-0.957), which indicates an excellent reliability. A weak correlation of 0.386 (P = .052) between the first MAT and the overall outcome of the MFIQ was found. A significant moderate correlation of 0.401 (P = .042) was found between the retest of the MAT and the overall outcome of the MFIQ. One question on the MFIQ (about yawning) showed a moderate positive correlation of 0.569 (P = .002) and 0.416 (P = .034) for the MAT test and retest, respectively. CONCLUSION: The MAT is an easy test to use in follow-up of patients. The test-retest reliability of this test is excellent in condylar trauma patients. As the validity of the MAT and the MFIQ could not be confirmed, the MFIQ may be an addition to patient's feedback about the rehabilitation process of their mandibular functioning.

A pilot study of masticatory function after maxillectomy comparing rehabilitation with an obturator prosthesis and reconstruction with a digitally planned, prefabricated, free, vascularized fibula flap.

STATEMENT OF PROBLEM: Oral rehabilitation after maxillectomy can be performed by prosthetic obturation or with a free fibula flap. Successful prosthetic obturation of large maxillectomy defects can be difficult, and masticatory function is at risk in these patients. Surgical reconstruction might provide adequate masticatory function, but the literature is lacking evidence regarding this topic. PURPOSE: The purpose of this pilot clinical study was to assess masticatory functions and health-related quality of life (HR-QoL) outcomes in patients after maxillectomy reconstructed by using the Rohner or the Alberta Reconstructive Technique and to compare outcomes with patients rehabilitated with an obturator prosthesis. MATERIAL AND METHODS: Mixing ability, maximum occlusal force, maximum mouth opening, and HR-QoL were assessed. Differences between the 2 groups were analyzed by using the Kruskal-Wallis tests for continuous variables and chi-squared tests for categorical variables. RESULTS: The reconstructed patients (n=11) showed better mixing ability, occlusal force (nonoperated side), and overall mean HR-QoL. The nonreconstructed group (n=13) did not differ from the reconstructed groups in terms of maximum mouth opening, overall mean occlusal force, occlusal force on the operated side, and most HR-QoL questionnaire domains. CONCLUSIONS: Maxillary reconstruction might be beneficial for masticatory performance in patients undergoing maxillectomy. A larger study is justified to support the possible benefit of the reconstruction of maxillary defects regarding mixing ability, occlusal force (nonoperated side), and HR-QoL.

The association between a mixing ability test and patient reported chewing ability in patients treated for oral malignancies.

INTRODUCTION: Mastication has been assessed in several ways in the past. Both patients reported and objective assessment methods have been developed. The University Medical Center (UMC) Utrecht has developed a mixing ability test (MAT) using a two-coloured wax tablet. The present study investigates the association between the mixing ability test and a chewing related questionnaire in patients treated for oral malignancies. PATIENTS AND METHODS: In a cohort study, patients treated for oral malignancies were assessed 4-6 weeks before and 4-6 weeks after treatment, as well as 6 months, 1 year and 5 years after treatment. The mixing ability test was assessed using 10 and 20 chewing strokes and was compared to seven questions about several aspects of mastication. Regression analysis was performed and density plots were drawn for statistical analysis. RESULTS: One hundred and twenty-three patients were included in this study. The questionnaire was less predictive for the 10-chewing stroke test and the test was less discriminatory for different food types than the 20-chewing stroke mixing ability test. Three questions about the ability to chew solid, soft and thickened liquid food types were found to be significantly predictive for the 20-chewing stroke test. Threshold values on the mixing ability index were around 20 for the ability to chew solid food types and 24 for soft food types. CONCLUSION: The 10-chewing stroke mixing ability test is less suitable than 20-chewing strokes for patients with and treated for oral cancer. The 20-chewing stroke mixing ability test has a fair association with self-reported outcomes.

Early and late complications in the reconstructed mandible with free fibula flaps.

BACKGROUND AND OBJECTIVES: Evaluation of mandibular reconstructions with free fibula flaps. Identification of factors associated with major recipient site complications, that is, necessitating surgical intervention under general anaesthesia. METHODS: Seventy-nine reconstructions were included. The following factors were analyzed: fixation type, number of osteotomies, site of defect (bilateral/unilateral), surgeon, sex, ASA classification, continuous smoking, pathological N-stage, age, defect size, flap ischemic time, and postoperative radiotherapy. Proportional hazards regression was used to test the effect on the time between reconstruction and intervention. RESULTS: Sixty-nine (87%) of the 79 fibula flaps were successful at the last follow-up. Forty-eight major recipient site complications occurred in 41 reconstructions. Nineteen complications required surgical intervention within six weeks and were mostly vascular problems, necessitating immediate intervention. These early complications were associated with defects crossing the midline, with an estimated relative risk of 5.3 (CI 1.1-20, P = 0.01). Twenty-nine complications required surgical intervention more than 6 weeks after the reconstruction. These late complications generally occurred after months or years, and were associated with smoking, with an estimated relative risk of 2.8 (CI 1.0-8.3, P = 0.05). CONCLUSIONS: Fibula flaps crossing the midline have a higher risk of early major recipient site complications than unilateral reconstructions. Smoking increases the risk of late complications.

Microstructured ß-Tricalcium Phosphate Putty Versus Autologous Bone for Repair of Alveolar Clefts in a Goat Model.

For the first time it was demonstrated that an osteoinductive calcium phosphate-based putty is effective in the restoration of complex maxillofacial defects. In these defects, adequate mechanical confinement by multiple bony walls and osteoconduction from multiple surfaces are usually lacking. This study compares the efficacy of a microstructured beta-tricalcium phosphate (ß-TCP) putty with autologous bone for the repair of alveolar cleft defects. A total of 10 Dutch milk goats were operated on in a split-mouth study design in which two-wall bony alveolar clefts were created and successively repaired with autologous bone (the gold standard) at one side and ß-TCP putty at the other. After 24 weeks of implantation, histomorphometric and micro-computer tomography analyses proved that the ß-TCP putty group showed equal bone quality and volume to clefts reconstructed with autologous bone. In addition, surgical handling of the putty is superior to the use of calcium phosphates in a granular form. Therefore, the results of this study open a clear trajectory for the clinical use of ß-TCP putty in the reconstruction of the alveolar cleft and other challenging two-wall bony defects.

Management of the premaxilla in the treatment of bilateral cleft of lip and palate: what can the literature tell us?

OBJECTIVE: In the treatment of bilateral cleft lip and palate (BCLP) patients, there is discussion about the management of the position of the premaxilla. This literature analysis summarises the literature on managing this condition. MATERIALS AND METHODS: A PubMed, Embase and Cochrane Library search was conducted resulting in 4465 articles which were screened on title and abstract. RESULTS: Seventy-one articles were available in full text, 16 of which were included in this literature analysis. We searched on keywords timing and technique, complications, growth of the maxilla and results after bone grafting the alveolar process. This literature analysis has shown that there are various ways to correct the position of the premaxilla. These can be divided into primary, early, late secondary and tertiary intervention before the age of 8 years, between the ages of 8 and 12 years and older than 12 years. Correction is done with surgery, orthodontics or a combination, with or without bone grafting. CONCLUSIONS: An osteotomy of the premaxilla in combination with secondary alveolar bone grafting appears to be the most successful technique. Combining early secondary alveolar bone grafting with osteotomy creates more room to ensure a watertight closure of the nasal mucosa resulting in fewer postoperative complications. Before surgery, the orthodontist should try to optimise the position of the premaxilla for its surgical correction prior to bone grafting. CLINICAL RELEVANCE: The treatment of BCLP patients is still based on experience and expert opinions. This literature analysis tries to give a summery on how to handle the protruded and displaced premaxilla.

Tissue engineering strategies for alveolar cleft reconstruction: a systematic review of the literature.

OBJECTIVES: To date, a great number of tissue engineering strategies have been suggested for alveolar cleft reconstruction; however, autologous bone grafting seems to remain the golden standard. MATERIALS AND METHODS: A systematic review of the literature was conducted in order to evaluate the clinical evidence pertaining to enhancement or replacement of the autologous bone graft in the alveolar cleft by means of tissue-engineered substitutes; 16 articles were selected for analysis. RESULTS: Tissue engineering strategies for alveolar cleft grafting included enhancing the autologous bone graft by means of platelet-rich plasma addition, the use of barrier membranes and fibrin glue, extension of the autologous graft with calcium phosphate scaffolds, and replacement of the graft using bone morphogenetic protein-2, mesenchymal stem cells, or calcium phosphate scaffolds. CONCLUSIONS: Selected articles showed a vast heterogeneity in data acquisition and patient selection. Therefore, a meta-analysis could not be performed. Future publications concerning this topic should be methodologically sound and preferably use three-dimensional radiological imaging for pre- and postoperative results. CLINICAL RELEVANCE: Bypassing or enhancing autologous bone grafting by means of tissue engineering solutions has become an important topic in alveolar cleft grafting. Replacement of the autologous bone graft will result in absence of donor site morbidity in this predominantly young population.

Long-term masticatory performance and ability following closed treatment for unilateral mandibular condylar neck or base fractures: a cross-sectional study.

PURPOSE: The aim of this study was to find explanatory variables for objective and patient-reported long-term masticatory functioning in patients treated with maxillomandibular fixation for unilateral condylar neck or base fractures. These outcomes were compared to healthy control subjects. METHODS: Patients treated between 1996 and 2013 were enrolled in the study. Objective measurements included the mixing ability test (MAT) for masticatory performance, and range of motion of the mandible. Patient-reported measurements included the mandibular function impairment questionnaire (MFIQ) for masticatory ability, and the visual analogue scale for pain. Healthy subjects were recruited between October 2018 and January 2019, and performed the MAT and MFIQ. RESULTS: Twenty-one patients and 30 healthy subjects were included. The average follow-up period was 11.67 years. In adjusted regression analysis, the amount of occlusal units (OU) was associated with the MAT (P = 0.020; R2 = 0.253) and MFIQ (P = 0.001, R2 = 0.454). The MAT outcome was similar in both groups when correcting for OU (P = 0.001; R2 = 0.201). The MFIQ was inferior in the patient group (P = 0.001). CONCLUSION: Long-term masticatory performance was similar in patients with a history of condylar neck or base fracture and healthy subjects; however, masticatory ability was inferior in patients compared to healthy subjects.

Reliability and measurement error of anterior maximum voluntary bite force in children with juvenile idiopathic arthritis and healthy children.

In children with juvenile idiopathic arthritis (JIA) the temporomandibular joint (TMJ) can be involved. As a consequence, the oral function can be impaired due to joint and/or muscle involvement of the masticatory system with a negative influence on the maximum bite force. The aim of this cross-sectional study was to establish the reliability of AMVBF in children with JIA and healthy children. Children with JIA and healthy children conducted three attempts of AMVBF. The reliability of AMVBF measurement was determined by the intra-class correlation coefficient (ICC) by age, standard error of measurement (SEM), smallest detectable change (SDC), and limits of agreement (LoA). A total of 298 children with JIA and 168 healthy children were examined. The AMVBF measurements showed an good to excellent reliability in children with JIA based on the ICCs corrected for age (0.782-0.979). In healthy children, the reliability was moderate to excellent (0.546-0.999). The SDC in our study indicated that values above 11.4N might be a clinical relevant change over time in children with JIA. The LoA showed a wide spread of variability in both children with JIA (-72.6-44.4N) and healthy children (-79.9-72.8N). The Bland-Altman plots indicated that the differences between the test and retest increased in value proportionally to the biteforce value.