[Recognizing and preventing disturbances in eruption]. / Herkennen en voorkomen van eruptiestoornissen.

Disturbances in eruption and related problems are quite common in permanent dentition but rare in deciduous dentition. For the timely recognition of disturbances in eruption, knowledge of the normal development of dentition is essential. Disturbances in eruption comprise disturbances in which eruption does not occur at all, in which it is delayed or incomplete, or in which the normal direction of eruption is influenced. If identified early enough, many undesirable dental conditions can be avoided or their seriousness can be limited. A possible impacting of permanent cuspids, for example, can be avoided by extracting the deciduous cuspids at the right moment; in cases of a large overjet or the threat of a cover-bite, lip interference can be prevented.

Proxy measurements in multiple sclerosis: agreement on different patient-reported outcome scales.

BACKGROUND: Patient-reported outcome (PRO) scales are often used in multiple sclerosis (MS) research. Full understanding of items can be influenced by disease worsening, mood disturbances and cognitive problems of the MS patient. Earlier research with the Multiple Sclerosis Impact Scale (MSIS-29) showed that proxy respondents (i.e. partners of patients) can provide useful information. OBJECTIVE: To determine agreement between patients and proxy respondents on different MS PRO scales. METHODS: 139 Patients and partners completed the MSIS-29 (Physical and Psychological scale), Multiple Sclerosis Walking Scale (MSWS-12), Multiple Sclerosis Neuropsychological Screening Questionnaire (MSNQ) and Guy's Neurological Disability Scale (GNDS). We calculated the mean difference and intra-class correlation coefficients (ICC) on scale level and weighted kappas (κ(w)) on item level. RESULTS: On all scales, except MSNQ, the partner score was higher. ICCs were good for MSWS, GNDS and MSIS Physical, and moderate for MSNQ and MSIS Psychological. κ(w) was excellent for MSWS items, fair to good for GNDS, MSIS Physical and MSIS Psychological items, and poor for MSNQ items. CONCLUSION: Partners of patients with MS can be a useful source of information for several PRO scales, especially when the focus is on physical functioning. For psychological functioning this seems to be less reliable.

Disease progression in multiple sclerosis: combining physicians' and patients' perspectives?

BACKGROUND: To assess disease progression in multiple sclerosis (MS) several outcome measures are available. The interrelation of changes on different scales has not been studied extensively and the concept of combining scales has only recently been introduced in MS. OBJECTIVE: To explore combining different clinical outcome measures in the evaluation of disease progression in MS. METHODS: In 553 patients we studied the presence of relevant changes according to standard definitions on the Expanded Disability Status Scale (EDSS), Nine-Hole Peg Test (9HPT), Timed 25-Foot Walk (T25FW) and the Multiple Sclerosis Impact Scale (MSIS-29). We examined 'exclusive worsening' (worsening on one measure while not worsening on any other measure) and 'opposing changes' (worsening on one measure while improving on another measure). Finally, we investigated the impact of combining assessments. RESULTS: Based on the EDSS alone, 140 patients progressed. However, almost twice as many (275) showed worsening on any of the clinical outcome measures. Exclusive worsening was observed in 37 patients on the EDSS, 13 on the 9HPT, 39 on the T25FW and 44 on the MSIS physical. Of all worsened patients 76 (28%) showed opposing changes, a phenomenon predominantly observed when combining physician-based and patient-derived outcome measures. CONCLUSION: When assessing disease progression in MS, sensitivity to change can be increased by combining different outcome measures. The added value is especially present when combining measures from different perspectives. However, further research is needed to evaluate the optimal way to combine outcome measures before implementing this strategy in clinical studies.

Proxy ratings from multiple sources: disagreement on the impact of multiple sclerosis on daily life.

BACKGROUND AND PURPOSE: The use of self-report measurements may be problematic in patients with limitations that interfere with reliable self-assessment like cognitive impairment, as may be the case in multiple sclerosis (MS). In these situations proxy respondents, such as close relatives or healthcare providers, may provide valuable information. To examine the accuracy and value of healthcare providers and close relatives to assess disease impact of MS. METHODS: MS patients, close relatives and healthcare providers completed the Multiple Sclerosis Impact Scale (MSIS-29) before and after a rehabilitation program. Agreement between outcomes was assessed by calculating mean absolute and directional differences and intraclass correlation coefficients. RESULTS: Comparison of ratings between patients and proxy respondents revealed low levels of agreement. Close relatives appeared to significantly overestimate the disease impact of MS whereas healthcare providers tended to underestimate the disease impact of MS. CONCLUSION: Caution is advised when incorporating close relatives and healthcare providers as proxy respondents in a rehabilitation setting. However, when close relatives are consulted, one should expect a certain level of overestimation of disease impact. When consulting healthcare providers, one should expect a certain level of underestimation of disease impact.

Proxy measurements in multiple sclerosis: agreement between patients and their partners on the impact of multiple sclerosis in daily life.

BACKGROUND: The use of self-report measurements in clinical settings has increased. The underlying assumption for self-report measurements is that the patient understands the questions fully and is able to give a reliable assessment of his or her own health status. This might be problematic in patients with limitations that interfere with reliable self-assessment such as cognitive impairment or serious mood disturbances, as may be the case in multiple sclerosis. In these situations proxies may provide valuable information, provided we can be certain that proxies and patients give consistent ratings. OBJECTIVE: To examine whether patients with multiple sclerosis and their partners agree on the impact of multiple sclerosis on the daily life of the patient by using the Multiple Sclerosis Impact Scale (MSIS-29). METHODS: 59 patients with multiple sclerosis and their partners completed the MSIS-29. Agreement was examined, comprehensively at scale score levels and item functioning, using both traditional and less conventional psychometric methods (Rasch analysis). RESULTS: Agreement between patients and partners was good for the physical scale, and slightly less but still adequate for the psychological scale. Mean directional differences did not show considerable systematic bias between patients and proxies. Intraclass correlation coefficients (ICCs) satisfied the requirements for agreement, but were higher for the physical scale (0.81) than for the psychological scale (0.72). These findings were supported by Rasch analyses. CONCLUSION: In this sample, albeit small, partners provided accurate estimates of the impact of multiple sclerosis. This supports the value of self-rating scales and indicates that partners might be useful sources of information when assessing the impact of multiple sclerosis on the daily life of patients.

[Mental and physical health problems of, and the use of healthcare by, Afghan, Iranian and Somali asylum seekers and refugees]. / Psychische en lichamelijke gezondheidsproblemen van en gebruik van zorg door Afghaanse, Iraanse en Somalische asielzoekers en vluchtelingen.

OBJECTIVE: To estimate the prevalence rates of mental and physical health problems and the use of healthcare services among adult asylum seekers and recognised refugees from Afghanistan, Iran and Somalia in the Netherlands. DESIGN: Cross-sectional study. METHOD: Asylum seekers were approached in 14 reception centres and refugees were interviewed in 3 municipalities (Arnhem, Leiden and Zaanstad). Respondents were interviewed in their own language and asked questions pertaining to: general health, chronic complaints, symptoms of post-traumatic stress disorder (PTSD), symptoms of depression/ anxiety, the use of healthcare services (general practitioner, medical specialists, hospitalisation, mental-health services, medication) and background variables. RESULTS: A total of 232 asylum seekers and 178 refugees participated (response rates of89% and 59%, respectively). Of these, 142 (61%) and 99 (56%), respectively were males and the average age was 34.4 (SD: 11.o) and 40.3 (SD: 13.3) years, respectively. Compared to refugees, asylum seekers more often considered their health to be poor (42% and 59%, respectively), had more symptoms of depression/anxiety (39% and 68%, respectively), and had more symptoms of PTSD (11% and 28%, respectively). No differences were found between refugees and asylum seekers in the self-reported use of healthcare services. CONCLUSION: This study showed that asylum seekers have more health problems than refugees, but that there are no differences in the self-reported use of healthcare services. More research is needed to answer the question ifasylum seekers have sufficient access to the healthcare system.

Bovine natural antibodies in antibody-dependent bactericidal activity against Escherichia coli and Salmonella Typhimurium and risk of mastitis.

Natural antibodies (NAbs) are mostly IgM antibodies produced without antigenic stimulation and serve as a first line of defence of the immune system. As both natural and specific antibodies are present in animals, NAbs are studied by determining the IgM response to naïve antigens like keyhole limpet hemocyanin (KLH). In this study, we selected cows based on high and low anti-KLH IgM titers, reflecting high and low NAb titers, and determined if the anti-KLH IgM titers were indicative for the recognition of common microbial structures (lipopolysaccharide, lipoteichoic acid and peptidoglycan) and intact bacteria (Escherichia coli and Salmonella Typhimurium). Sera with high NAbs titers showed more IgM and IgG binding to common microbial structures and S. Typhimurium bacteria than sera with low NAbs titers. The same association was observed for IgM binding to E. coli, but not for IgG binding to E. coli. Antibody-mediated complement killing of E. coli and S. Typhimurium in a newly developed bactericidal test was equal between high and low NAb cows. However, relating the outcome of the bactericidal test to the development of mastitis within one and even four years after sampling showed a significant negative correlation implying cows that were less potent in bacterial killing had a higher chance on developing mastitis. In conclusion, sera with high NAbs titers had more antibodies binding to common microbial structures and intact bacteria. Furthermore, the bactericidal test might provide a useful prognostic tool for the development of mastitis.

Similar hospital morbidity with the use of one or two internal thoracic arteries.

The hospital morbidity and mortality of 100 patients operated with two internal thoracic arteries with or without additional vein grafts (BITA group) were compared with a matched group of 100 patients operated with one left internal thoracic artery (ITA) on the anterior descending artery with additional vein grafts (LITA control group). In each study group, 3% of the patients had diabetes mellitus. There was no statistical significant difference in hospital mortality (1% versus 0%), perioperative myocardial infarction (5% versus 1%), low cardiac output (3% versus 5%), rethoracotomy (1% versus 0%), lung complications (13% versus 13%), wound complications (8% versus 8%), other cardiac complications (26% versus 16%), other noncardiac complications (1% versus 4%), median duration of stay in the intensive care unit (1 versus 1 day), and mean duration of stay in the hospital (10.4 versus 10.8 days) between the groups. Logistic regression analysis showed that the number of ITAs used was not a predictor of complications. Thus, there is no difference between the BITA and LITA control group in hospital mortality and morbidity (in patients with a low incidence of diabetes). If an improvement in cardiac event-free and reoperation-free survival is to be expected, the use of both ITAs can be continued in similar patients.

Does it make sense to use two internal thoracic arteries?

Retrospectively, the first 143 patients who were operated on with bilateral internal thoracic arteries (BITA group) were matched with 143 patients operated on with only one left internal thoracic artery anastomosed on the left anterior descending artery and additional vein grafts (LITA group) and followed up for a maximum of 8 years. At 5 years follow-up there were no significant differences in event-free survival between the groups. After 8 years, the overall survival was 96% and 92% (not significant [NS]), cardiac survival 99% and 97% (NS), angina-free cardiac survival 51% and 35% (NS), infarction-free cardiac survival 95% and 78% (NS), reintervention-free cardiac survival 87% and 88% (NS), and all cardiac event-free survival 49% and 31% (NS) for the BITA and LITA groups, respectively. The incidence of late pulmonary, wound, and other complications was comparable. Cox proportional hazards analysis showed that a higher left ventricular end-diastolic pressure and female sex were predictors of recurrent angina and late cardiac events. During this intermediate-term follow-up, the use of one or two internal thoracic arteries was of no value in predicting angina-free or cardiac event-free survival.

Creating phyllotaxis: the stack-and-drag model.

The genesis of phyllotaxis, the origin of the pattern of appendages on the surface just below the apical extreme of many plants, is an old unsolved puzzle. Whereas many models generate helices, the stack-and-drag model is the first to achieve this in an integral construction from seed to flower. Combination of the principle of gnomonic growth, where consecutive additions have comparable positions, with a "dragging" principle, where the developing zone follows the apical tip, provides a powerful tool in simulating a wide range of phyllotactic manifestations. The influence of three vital parameters for primordial size, compressibility, and canalization (or annular arrangement) helps in understanding the problem's nature.

Creating phyllotaxis: the dislodgement model.

Assuming that neither the Fibonacci sequence nor any numerical ratio or angular deflection is specified in the genetic material of a plant cell, there must be an arranging mechanism effecting the sequence mentioned. Considering the ubiquity of the Fibonacci numbers in nature, embracing many species of flora, we expect a very simple geometrical law to be responsible. Success in finding such a law does not constitute a proof, but it is at the least an indication that we should look here with mathematical rather than biological eyes. The idea may seem self-evident. However, in the literature it has not yet been honored as the basis for constructing the phyllotaxis in centric, planar models. It is shown here that for the construction of a phyllotactic structure, no special angles or distances need be defined; natural growth functions can be used; planar, cylindrical, conical, and paraboloid constructions are possible within the same model; and constructions leading to accessory sequences and multijugate sequences can also be carried out.

Skeletal and dento-alveolar stability of Le Fort I intrusion osteotomies and bimaxillary osteotomies in anterior open bite deformities. A retrospective three-centre study.

A sample of 267 patients with maxillary hyperplasia, a Class I or Class II/I occlusion and anterior vertical open bites, collected from three different institutions, was analysed regarding stability after surgical corrections. Skeletal and dento-alveolar stability of the maxilla, and positional changes of the mandible and of the incisors were evaluated. All patients underwent Le Fort I intrusion osteotomies and in 92 patients segmentation of the maxillae was performed. An additional bilateral sagittal split advancement osteotomy was performed in 123 patients. Intraosseous wire fixation was used in 153 patients and rigid internal fixation in 114 patients. Cephalometric radiographs were collected before orthodontic treatment, before surgery, immediately after surgery, one year postoperatively and at the latest follow up. The mean follow up was 69 months (range 20-210 months). It can be concluded that patients with anterior open bites, treated with a Le Fort I osteotomy in one-piece or in multi-segments, with or without bilateral sagittal split osteotomy, exhibited good skeletal stability of the maxilla. Rigid internal fixation produced the best maxillary and mandibular stability. The mean overbite at the longest follow up was 1.24 mm and a lack of overlap between opposing incisors was present in 19%. The overbite did not differ significantly between the different treatment procedures, probably due to compensatory movements of the mandibular and maxillary incisors.

4D-computerized visualisation of human craniofacial skeletal growth and of the development of the dentition.

The understanding of growth and developmental changes can be improved when shapes and changes in size, proportion, and relationships are visualized in 3 dimensions and at different stages. This applies particularly to craniofacial skeletal growth and the development of the dentition. For that purpose 3D-data were collected from prenatal human heads ranging from 18 up to 275 mm CRL and from a collection of macerated fetal and postnatal skulls. Computer-aided graphical reconstructions were obtained from histological serial sections of embryonic and early fetal specimens. Proportional changes in the growing skull were recorded by means of radiological and cephalometric evaluation. In addition, computed tomography was applied to fetal and postnatal skulls. Furthermore, the prenatal and postnatal development of the dentition was digitized. To that end 3D-polygone sets of these data were read into a workstation computer and animated by means of the software Soft Image (Microsoft). This comprehensive 4D insight into growth facilitates the understanding and teaching of normal and abnormal development.

Perceptions of dentofacial morphology by laypersons, general dentists, and orthodontists.

Line drawings of facial profiles and color photographs of dentitions were evaluated subjectively by 1,150 parents, 72 general practictioners of dentistry, and 54 orthodontists with regard to the normality and abnormality in dentofacial morphology and the need for orthodontic treatment. A significant difference was found between the evaluations of the parents and the professional groups in ten of the 11 facial profiles and in seven of the 11 photographs of dentitions. In general, the parents considered more of the examples acceptable and not requiring orthodontic treatment than did the professional groups. The dentists and orthodontists deviated significantly in their ratings onjy in their judgement of "ugly duckling" example (picture 22, higher abnormal rating by the dentists) and the profile example 10 (higher abnormal rating by orthodontists). number of orthondontists may have associated the conditions in picture 10 with a Class II, Division 2 malocclusion and, as such, scored it abnormal.

The role of intercuspation in the regulation of transverse maxillary development in Macaca fascicularis.

The role of intercuspation of the teeth in transverse maxillary growth and dental arch development was investigated radiographically with the aid of implants in Macaca fascicularis monkeys. Fourteen animals were randomly allocated to a control group (n = 7) and an experimental group (n = 7) and were followed from 29 to 100 weeks of age. Intercuspation was eliminated in the experimental group by grinding the canines and molar cusps in both dental arches as soon as possible after emergence. Maxillary occlusal radiographs were taken at regular intervals. Linear and angular analyses of skeletal changes revealed that midpalatal sutural growth seems to be independent of intercuspation. The developing dental arch, however, showed a significantly greater increase in width in certain areas in the experimental group than in the control group. Most findings support the hypothesis that the width of the maxillary dental arch is guided by the width of the mandible through the intercuspation of the posterior teeth.

[Orthodontic possibilities for young patients with missing maxillary incisors]. / Orthodontische mogelijkheden bij jeugdige patiënten met ontbrekende bovensnijtanden.

In the orthodontic treatment of young patients with missing maxillary incisors one should make an effort to avoid prosthetic solutions. This not only applies to situations with agenesis of maxillary lateral permanent incisors, but also to those cases in which maxillary incisors cannot be maintained after trauma. Standard solutions are presented for various sagittal jaw relationships and types and number of teeth missing. Specific rules have to be observed for the closure of spaces due to missing teeth in order to reduce the occurrence of papillae retraction and to place the substituting teeth in such a position that their crowns can be built up to look like the originals. This requires mesiodistal angulations that deviate from the standard ones, a proper distribution of crown width and in most cases a permanent retention with a palatally bonded thin multistranded wire.

[Dental curriculum in Nijmegen]. / Het Nijmeegse curriculum tandheelkunde.

The dental curriculum at the University of Nijmegen is based on what the dentist should know and be able to do after his graduation. The programme is divided up into cognitive, behavioural and motoric modules. These modules are vertically connected through subsequent course years by thematically related lines. For every module, the general objectives and general contents have been formulated. Moreover, all subcomponents have been specified as instructional objectives. Half of the study hours is reserved for practical dentistry, by means of preclinically laboratory courses or patient treatment. The curriculum is based on a scientific approach of dentistry and emphasis is placed on patient related instructional situations.

[The 'van der Linden' retainer]. / De Van der Linden-retainer.

Normally, only the anterior teeth have to be retained after an orthodontic treatment. For that purpose, a lingually bonded wire is preferred in the mandible and a removable plate in the maxilla. The design of the Van der Linden-retainer is based on theoretical considerations and secures rigid fixation of the six anterior teeth with solid anchorage in that region. A retention plate should not be used to move anterior teeth. However, with instant corrections small improvements can be realized. The fabrication and clinical use of the Van der Linden-retainer is explained and illustrated.

[Anterior open bite]. / Open beet in het front.

In almost 50% of the Dutch population, the mandibular incisors do not contact the maxillary ones. An open bite is usually based on an interposition of the tongue and can be combined with other functional disturbances as digit sucking. A large open bite with an excessive facial deformity can be treated adequately, after facial growth is completed, by a combined orthodontic-surgical approach, in which a good cooperation between the orthodontist and the oral surgeon is essential. The correction of the facial deformity is of a permanent nature. That does not always apply to the open bite due to interposition of the tongue. Often it is not possible to arrive at complete contact by orthodontic or surgical means. The improvement realized can fade away partly in the years following.

[Shape and/or colour anomalies of anterior teeth]. / Vorm-en kleurafwijkingen van frontelementen. Correctie met composiet als alternatief voor, of ter completering van orthodontische behandeling.

Many esthetically unpleasant positions of teeth can be improved by orthodontic treatment but can also be camouflaged by built-ups with composite resins in combination with grinding of enamel. With this method orthodontic results can also be improved and relapses corrected. The technique and different possibilities are described and demonstrated with clinical examples.