MKA en de Juiste Maat

Rede, uitgesproken bij de aanvaarding van het ambt van hoogleraar in de Mondziekten, Kaak- en Aangezichtschirurgie en Bijzondere Tandheelkunde aan het Erasmus MC, faculteit van de Erasmus Universiteit Rotterda

Allogeneic chondrogenically differentiated human bone marrow stromal cells do not induce dendritic cell maturation

Bone marrow stromal cell (BMSC)-mediated endochondral bone formation may be a promising alternative to the current gold standards of autologous bone transplantation, in the development of novel methods for bone repair. Implantation of chondrogenically differentiated BMSCs leads to bone formation in vivo via endochondral ossification. The success of this bone formation in an allogeneic system depends upon the interaction between the implanted constructs and the host immune system. The current study investigated the effect of chondrogenically differentiated human bone marrow stromal cell (hBMSC) pellets on the maturation and function of dendritic cells (DCs) by directly coculturing bone forming chondrogenic hBMSC pellets and immature or lipopolysaccharide (LPS)-matured DCs in vitro. Allogeneic chondrogenic hBMSC pellets did not affect the expression of CD80, CD86, or HLADR on immature or LPS-matured DCs following 24, 48, or 72 hr of coculture. Furthermore, they did not induce or inhibit antigen uptake or migration of the DCs over time. IL-6 was secreted by allogeneic chondrogenic hBMSC pellets in response to LPS-matured DCs. Overall, this study has demonstrated that maturation of immature DCs was not influenced by allogeneic chondrogenic hBMSC pellets. This suggests that allogeneic chondrogenic hBMSC pellets do not stimulate immunogenic responses from DCs in vitro and are not expected to indirectly activate T cells via DCs. For this reason, allogeneic chondrogenic bone marrow stromal cell pellets are promising candidates for future tissue engineering strategies utilising allogeneic cells for bone repair

Effectiveness of the new mandatory mouthguard use and orodental injuries in Dutch field hockey

Objectives Up to 68% of field hockey players have experienced at least one orodental injury in their sport career. Therefore, the Royal Dutch Hockey Association (KNHB) made mouthguard use mandatory for field hockey players during competition and training from August 2015 onwards. This study evaluates the effects of the new regulations on mouthguard use and the occurrence of injuries in Dutch field hockey. Methods A 35-item online questionnaire about mouthguard use and orodental injuries was sent to 13 field hockey clubs in the Netherlands. Absolute numbers and percentages of mouthguard ownership, mouthguard use, number and type of injuries were assessed. The results were related to comparable data before mandatory mouthguard use. Associations of gender and training frequency with the number of injuries were analysed with logistic regression. Results In total, 1169 hockey players were included in the study and almost all owned a mouthguard (females:99.6%, males:93.7%), which significantly increased after implementation (p < 0.001). 90.6% of the respondents wore a mouthguard during matches and 70.1% during training. Of the 1169 players, 68(5.8%) experienced at least one orodental injury after the implementation with a total of 100 injuries. Injuries happened more often during matches (63.2%) than during training (36.8%). Lip cuts account for most of the injuries, the number of broken (p = 0.116) and knocked out teeth (p = 0.026) decreased. Conclusion Although mouthguard use already increased in recent years, the new regulations led to an additional increase and a successful change of attitude towards mouthguard use. Most importantly, the severity of orodental injuries decreased measurable

Electrocardiographic variables in children with syndromic craniosynostosis and primary snoring to mild obstructive sleep apnea

Background: In the spectrum of children with symptomatic sleep disordered breathing (SDB), some individuals – such as those with upper airway resistance syndrome (UARS) – do not have abnormalities on polysomnography (PSG). In this study we have assessed whether assessment of respiratory arrhythmia (RA) and heart rate variability (HRV) analysis helps in management of children with syndromic craniosynostosis and none-to-mild obstructive sleep apnea (OSA). Methods: Prospective cohort study in children aged 1–18 years old with syndromic craniosynostosis. Children were selected for HRV analysis from the ECG if their obstructive apnea–hypopnea index (oAHI) was between zero and five per hour (ie, oAHI ≤5/hour). Subjects were divided into groups based on the presence or absence of respiratory arrhythmia (with or without RA respectively) using the electrocardiogram (ECG). The main analysis included studying the relationship between RA and HRV, symptoms, interventions, and sleep architecture. Results: We identified 42 patients with, at worst, mild OSA. We found higher parasympathetic control and higher total power in children with RA during the non-rapid eye movement (non-REM) sleep. Children with RA also have a relatively higher percentage of paradoxical breathing during non-REM sleep (P = 0.042). Intracranial hypertension was distributed equally between groups. Last, RA patients showed increased parasympathetic activity that further increased in non-REM sleep. Conclusion: In syndromic craniosynostosis cases with SDB and PSG showing oAHI ≤5/hour, the presence of RA may indicate subsequent need for treatment interventions, and a trend toward higher occurrence of clinical symptoms. ECG analyses of HRV variables in subjects with RA demonstrate increased parasympathetic activity and total power. Such findings may add to the diagnosis of apparently asymptomatic children

Optical Imaging of Tumor Response to Hyperbaric Oxygen Treatment and Irradiation in an Orthotopic Mouse Model of Head and Neck Squamous Cell Carcinoma

Purpose: Hyperbaric oxygen therapy (HBOT) is used in the treatment of radiation-induced tissue injury but its effect on (residual) tumor tissue is indistinct and therefore investigated in this study. Procedures: Orthotopic FaDu tumors were established in mice, and the response of the (irradiated) tumors to HBOT was monitored by bioluminescence imaging. Near infrared fluorescence imaging using AngioSense750 and Hypoxisense680 was applied to detect tumor vascular permeability and hypoxia. Results: HBOT treatment resulted in accelerated growth of non-irradiated tumors, but mouse survival was improved. Tumor vascular leakiness and hypoxia were enhanced after HBOT, whereas histological characteristics, epithelial-to-mesenchymal transition markers, and metastatic incidence were not influenced. Conclusions: Squamous cell carcinoma responds to HBOT with respect to tumor growth, vascular permeability, and hypoxia, which may have implications for its use in cancer patients. The ability to longitudinally analyze tumor characteristics highlights the versatility and potential of optical imaging methods in oncological research

Skeletal maturation in relation to ethnic background in children of school age: The Generation R Study

Ethnicity is a well-established determinant of pediatric maturity, but the underlying genetic and environmental contributions to these ethnic differences are poorly comprehended. We aimed to evaluate the influence of ethnicity on skeletal age (SA), an assessment of pediatric maturation widely used in clinical settings. We included children from the Generation R Study, a multiethnic population-based pregnancy cohort, assessed at a mean age of 9.78 (±0.33) years. SA was evaluated by a trained observer on hand DXA scans using the Greulich and Pyle method. Ethnic background was defined as geographic ancestry (questionnaire-based assessment) (N = 5325) and genetic ancestry (based on admixture analysis) (N = 3413). Associations between the ethnic background and SA were investigated separately in boys and girls, using linear regression models adjusted for age, height and BMI. Based on geographic ancestry, 84% of the children were classified as European, 6% as Asian and 10% as African. Children of European background had on average younger SA than those of Asian or African descent. Asian boys had 0.46 (95% CI 0.26–0.66, p-value < 0.0001) and African boys 0.36 years (95% CI 0.20–0.53, p-value < 0.0001) older SA as compared to European boys. Similarly, Asian girls showed 0.64 (95% CI 0.51–0.77, p-value < 0.0001) and African girls 0.38 years (95% CI 0.27–0.48, p-value < 0.0001) older SA as compared to European girls. A similar pattern was observed in the analysis with genetically-defined ancestry. Furthermore, an increase in the proportion of Asian or African component was associated with older SA in both boys (log[Non-European/European]proportion = 0.10, 95% CI 0.06–0.13, p-value < 0.0001) and girls (log[Non-European/European]proportion = 0.06, 95% CI 0.04–0.08, p-value < 0.0001). In summary, children of Asian and African backgrounds have on average older SA as compared to children of European descent, partially explained by a genetic com

Oral health among Dutch elite athletes prior to Rio 2016

Objectives: Elite athletes are at high risk for poor oral health. A screening program to assess oral health and create dental awareness can improve oral health among elite athletes but has not been performed in the Netherlands before. We summarize the first results from such a screening conducted in Dutch elite athletes of the Nederlands Olympisch Committee*Nederlandse Sport Federatie (NOC*NSF, Dutch Olympic Committee). Methods: In this cross-sectional study, 800 Dutch athletes eligible for the Olympic and Paralympic Games in Rio de Janeiro 2016 were invited to a costless and voluntary oral examination. The decayed, missing, and filled teeth-index (DMFT), the basic erosive wear examination (BEWE) and the Dutch Periodontal Screening-index (DPSI) were used to evaluate athlete’s oral health. Information on sociodemographic variables and sport performance were collected in questionnaires. Results: In total, 116 Dutch elite athletes were included in the study. The median (90%-range) DMFT-score was 3.0 (0.0–16.0), the median BEWE-score was 2.0 (0.0–10.0), and the mean± SD DPSI-score was 2.0 ± 0.73. Oral health-related quality of life was generally high, although only 28.2% of the athletes reported never having problems with their dentition or mouth. In 43% of the athlete’s clinical findings were reported which needed a direct referral to the general dentist. Conclusion: Oral health in this subsample of Dutch elite athletes was surprisingly affected as almost half of them needed dental treatment. Further research is needed to allow conclusions about oral health in Dutch elite athletes more broadly. However, regular screening of oral health incorporated into the general preventive health care of elite athletes is necessary to ensure athletes are fully healthy during competitions like the Olympic and Paralympic Games

Ethnic background and children's oral health-related quality of life

Purpose Ethnic background is known to be related to oral health and socioeconomic position (SEP). In the context of patientcentered oral health care, and the growing number of migrant children, it is important to understand the influence of ethnic background on oral health-related quality of life (OHRQoL). Therefore, we aimed to identify the differences in children’s OHRQoL between ethnic groups, and the contribution of oral health status, SEP, and immigration characteristics. Methods This study was part of the Generation R Study, a prospective cohort study conducted in Rotterdam, the Netherlands. In total, 3121 9-year-old children with a native Dutch (n=2510), Indonesian (n=143), Moroccan (n=104), Surinamese (n=195), or Turkish (n=169) background participated in the present study. These ethnicities comprise the most common ethnic groups in the Netherlands. OHRQoL was assessed using a validated short form of the child oral health impact profile. Several regression models were used to study an association between ethnic background and OHRQoL, and to identify potential mediating factors. Results Turkish and Surinamese ethnic background were significantly associated with lower OHRQoL. After adjusting for mediating factors, only Surinamese children had a significantly lower OHRQoL than Dutch children (β:−0.61; 95% CI−1.18 to –0.04). Conclusions Our results show that Turkish and Surinamese children have a significantly lower OHRQoL than native Dutch children. The association was partly explained by oral health status and SEP, and future studies are needed to understand (cultural) the determinants of ethnic disparities in OHRQoL, in order to develop effective oral health programs targeting children of differe

Management and outcomes of obstructive sleep apnea in children with Robin sequence, a cross-sectional study

Objective: The objective of this cross-sectional study is to assess the prevalence, course, and management of obstructive sleep apnea (OSA) in children with Robin sequence (RS) aged 1–18 years. Materials and methods: A cross-sectional study was conducted in 63 children aged 1 to18 years with RS. Patient data were collected on baseline characteristics and management. OSA was evaluated by polysomnography. Results: Sixty-three children with RS were included (median age 8.0 years) and divided into two groups based on the initial treatment: prone positioning or respiratory support. Respiratory support was more often indicated in children with a non-isolated RS (p < 0.05). At cross section, in the prone positioning group (n = 32), one child was diagnosed with OSA. In the respiratory support group (n = 31), 13 children (42 %) had respiratory problems of whom 10 needed respiratory support. Conclusions: Between the age of 1 and 18 years, almost one out of four children with RS still has respiratory problems. Children with RS, who can be treated with prone positioning only as an infant, are not likely to develop obstructive airway problems at a later age. In contrast, children who need respiratory support early after birth are at risk of continuing or re-developing OSA after the age of 1 year. Clinical relevance: This study shows that those who need respiratory support at an early age need careful monitoring until adulthood

Influence of self-esteem on perceived orthodontic treatment need and oral health-related quality of life

Background: Self-esteem (SE) is suggested to influence the relationship between orthodontic treatment need and oral health related quality of life (OHRQoL), but evidence lacks. The aim of the present study was to investigate SE in the relationship between subjective orthodontic treatment need (SOT) and OHRQoL in children. Methods: This cross-sectional study was embedded in the Generation R Study, a multi-ethnic population-based cohort. In total, 3849 10-year old children participated in the present study. OHRQoL, measured with the Child Oral Health Impact Profile-ortho, and SOT were assessed within parental questionnaires. SE was measured with a modified version of the Harter’s self-perception profile rated by the children. The role of SE in the association between SOT and OHRQoL was evaluated with linear regression mode