[Cup-shaped tooth wear defects: more than erosive challenges?] / Komvormige defecten in occlusale vlakken van molaren: meer dan alleen erosieve belasting?

The underlying mechanism of the development of cups and grooves on occlusal tooth surfaces is still unclear. The aim of this study was to evaluate factors contributing to in-vitro cup formation, and to elucidate the clinical process. Extracted human molar teeth were exposed to acidic aqueous solutions at pH of 4.8 and 5.5 in combination with different loading conditions: no load (0N, control), 30N or 50N. Before and after 3 months exposure, the samples were scanned using a non-contact profilometer. A statistically significant difference between a loading of 0N and 50N was found at pH 4.8 (p < 0.002). Cup shaped lesions had formed only at pH of 4.8, in the 30N and 50N groups. The study showed that a cup can arise fully in enamel and that this requires simultaneous acidic and mechanical loading.

[A 14-year-old Syrian refugee with neurobrucellosis]. / Een 14-jarige Syrische vluchteling met neurobrucellose.

BACKGROUND: Neurobrucellosis is a rare complication of brucellosis, a bacterial zoonotic disease endemic in regions such as the Middle East. It is important to be alert for this imported disease in the Netherlands as well, especially among migrants. CASE DESCRIPTION: A 14-year-old boy from Syria presented with headache, vomiting and weight loss. Brucella melitensis was identified in the cerebrospinal fluid. The patient's condition deteriorated despite antibiotic treatment, particularly neurologically, and imaging revealed a newly developed hydrocephalus. The symptoms disappeared after placement of a temporary external ventricular drain. The patient made a complete recovery following 8 months of continual antibiotic therapy. CONCLUSION: Diagnosis and treatment were delayed, partly because there were no medical records available, previous treatment had been interrupted when the patient fled the country, and the language barrier. Knowledge of previous medical history and of the epidemiology of infectious diseases in the land of origin is particularly important when treating migrants. Treating brucellosis with antibiotics can lead to clinical deterioration due to a Jarisch-Herxheimer-like phenomenon.

[(Erosive) tooth wear in children and adolescents in the Netherlands: how big is the problem?] / (Erosieve) gebitsslijtage bij jeugdigen in Nederland: hoe groot is het probleem?

According to international research, the prevalence of (erosive) tooth wear among children and adolescents has grown steadily in recent decades. The question was whether this also applies to the Netherlands and what changes in consumption patterns may play a role in this development. From 1998 up to and including 2011, 9 studies have been carried out on the prevalence of (erosive) tooth wear among the young. A meta-analysis of these studies reveals that an increase has also taken place in the Netherlands. Furthermore, a tendency was found for greater prevalence with increasing age. It is generally assumed that changes in the supply of food and drink and therefore consumption patterns have been a major reason for this increase in children and adolescents. However, longitudinal studies, in which both the prevalence and incidence of (erosive) tooth wear are investigated, are needed to support these assumptions. Such studies are, however, scarce and, moreover, the results show no consistent picture.

Saliva parameters and erosive wear in adolescents.

The aim of this study was to investigate the relationship between several parameters of saliva and erosive wear in adolescents. (Un-)stimulated saliva was collected from 88 adolescents with erosion and 49 controls (age 16 ± 1 years). Flow rate, pH and buffer capacity were determined immediately. Total protein content, carbonic anhydrase VI, amylase, albumin, calcium, phosphate, urea, sodium, chloride and potassium were measured at a later time. Unstimulated flow rate was found to be significantly lower in subjects with erosive wear (p = 0.016). The chloride concentration in unstimulated saliva was found to be significantly higher in the erosion group (p = 0.019).

Organisational aspects of dental practices: do dental students think like patients or like general dental practitioners?

INTRODUCTION: In view of transparency in health care, the widespread desire for more patient-centred care, and in an attempt to facilitate educational programmes that effectively respond to these changes, two research questions are formulated: (i) How do dental students rate the importance of various organisational aspects of dental practices compared with dental patients and general dental practitioners (GDPs), and what prescripts, defined as specific operational responsibilities of GDPs in these matters, do dental students propose? and (ii) In doing so, do students resemble patients or GDPs? METHODS: In two survey studies, dental students (n = 198), patients (n = 3127) and GDPs (n = 303) were asked to rate by questionnaire the importance of 41 organisational aspects of a general dental practice and proposed specific operational responsibilities ('prescripts'). RESULTS: Seven of 41 aspects were rated as important by the majority of the students. Although in a different rank order, three aspects were predominantly selected by all three groups: continuing education, accessibility by telephone and Dutch-speaking GDP. For most aspects, significant differences were found between the prescripts proposed by students and those proposed by patients, and few differences were found between students and GDPs. CONCLUSION: The findings do not permit the general conclusion that the views of dental students resemble those of patients or GPDs. Looking at the overall rank order, the three respondent groups showed a great resemblance although significant differences were found for specific aspects. With regard to the proposed prescripts, students showed realistic views and the majority wants to participate in continuing education and work with protocols and guidelines. In this, they tend to resemble GDPs more than they resemble patients.

Multifactorial analysis of factors associated with the incidence and progression of erosive tooth wear.

To prevent erosive tooth wear, early diagnosis and identification of causative factors are essential. The aim of the present 3-year longitudinal study was to investigate the association between a broad collection of biological and behavioural factors and the incidence and progression of erosive tooth wear among adolescents. The study sample consisted of 656 attendees of a dental clinic with at baseline a mean age of 11.9 years (SD = 0.9). The criteria for the assessment of erosive wear were a modification of the erosion criteria developed by Lussi [Eur J Oral Sci 1996;104:191-198]. Information on biological and behavioural factors was gathered by clinical examinations (at baseline, after 1.5 and 3 years) and by self-reported questionnaires (completed semi-annually). Of the erosion-free children at baseline, 24.2% developed erosive wear. In children with erosion at baseline, 68.3% showed progression. Multivariate analyses showed significant associations between the incidence of erosive tooth wear and alcoholic mixed drinks (odds ratio, OR = 1.82), sour vegetables (OR = 1.16) and tooth grinding (OR = 4.03). The intake of yoghurt products was significantly negatively associated with the incidence of erosive wear (OR = 0.79). The interaction of acidic products and tooth grinding showed a significant extra risk (OR = 1.2). The intake of vitamins was positively associated with progression (OR = 2.03). Erosive wear was less likely to progress in subjects who consumed milk and yoghurt products (OR = 0.89 and 0.76, respectively). The present study showed that the aetiology of erosive tooth wear is complex. Possible aetiological factors include more than acidic drinks, and factors such as tooth grinding play a large role.

Does incomplete caries removal reduce strength of restored teeth?

Little information is available about whether the presence of residual caries beneath an occlusal restoration affects fracture strength of the tooth. This in vitro study tested the hypothesis that restored teeth after incomplete excavation have lower fracture strengths than restored teeth after complete excavation. Fourteen pairs of molars were randomly assigned to an experimental (incomplete excavation) or to a control group (complete excavation) and loaded vertically (after cyclic loading). Failure load and fracture mode were recorded. Restored teeth in the incomplete excavation group resulted in reduced fracture strength (p < 0.001) of the tooth-restoration complex (1276 N ± 626 N) compared with the control group (2768 N ± 710 N). Teeth in the complete excavation group all fractured vertically, while in the experimental group, cracks in the restoration were observed, characterized as 'ice-cracks'. The fracture strength of teeth restored over incomplete caries excavation was significantly reduced, possibly resulting in long-term clinical failure.

[Secular trends of caries prevalence among 6 and 12 year-old youths in the Netherlands]. / Trends in de prevalentie van cariës bij de 6- en 12-jarige jeugd in Nederland.

In order to gain insight into the development of caries prevalence and caries experience among Dutch youth, a meta-analysis was carried out on epidemiological caries data collected in 5 and 6 and 11 and 12 year-olds between 1980 and 2009. From the present analysis it appears that after the mid-1980's a halt occurred in the decline of caries experience in the primary dentition among 5 and 6 year-olds. At the same time, the percentage of children with a caries-free primary dentition who were covered by public health insurance or participated in institutions for youth dental care decreased. Among 11 to 12 year-olds there is no indication that the prevalence of caries in the permanent dentition has changed. Considering the high percentage of 12 year-olds with a caries-free permanent dentition, an additional improvement in oral health for this age-group will be difficult to achieve. The average restorative index of the primary dentition in 5-6 year-old children covered by public health insurance and children in The Hague appears not to have changed dramatically in the last 15 years.

Long-term performance of resin based fissure sealants placed in a general dental practice.

OBJECTIVES: The aim of the present retrospective study was to evaluate the long-term performance of resin based fissure sealants applied in a general dental practice. METHODS: Regularly attending patients visiting the practice between July 2006 until November 2007 and who had received sealants before 1st of January 2000 were included in the study. Date of placement of a sealant in posterior non-discoloured permanent teeth and replacement by a restoration was recorded. In a clinical examination occlusal surfaces were scored for (partial) sealant loss and fissure discolouration. The restoration profile of the patient was assessed as low or high, based on the number of restorations placed per year since the first sealant. Sealants had been applied by four dentists and a dental hygienist. RESULTS: 1204 sealants were placed in 148 patients. After a mean follow-up time of 11.6 years, 41.3% of placed sealants were still fully retained and 11.4% were replaced by a restoration. Failure rates were significantly higher in high than in low restoration profile patients and in molars compared to premolars. In those fissures with lost or partially lost sealants, discolouration frequently occurred (40% of all surfaces) irrespective of restoration profile of the patient. CONCLUSIONS: In this retrospective practice based study, long-term performance of sealants depended on restoration profile of the individual patient and the tooth type (molar versus premolar).

[Quality of dental care: new ideas of the government]. / Kwaliteit van zorg: nieuwe ideeën van de overheid.

In the 1990s the Dutch government imposed several laws to strengthen the position of the patient and to improve the quality of care. These laws did not always have the intended outcome. Recently the Ministry of Public Health, Welfare and Sport launched the programme, 'The 7 rights of the patient in health care: investing in health care relations'. Three of these rights will have a strong influence on Dutch general dental practices: the right to choice and choice-information, the right concerning coordination among oral health care providers, and the right to low-threshold complaint and disagreement procedures. Most of these rights already exist in current legislation. Especially the right to choice and choice-information means that the dentist has to provide his patients not only with information concerning treatment but also with information on his dental practice, such as waiting times, the experience of other patients and opening times.

[The restorative care index in children 2. Factors concerning the dentist]. / De restauratieve verzorgingsgraad bij de jeugd 2. Tandartsfactoren.

As part of a broader study of the restorative care index of 5- and 6-year-olds and 11- and 12-year-olds, a sample study was carried out among 1,361 dentists, who were surveyed by means of a web-questionnaire concerning this issue. In total 447 dentists (33%) filled in the questionnaire completely. Concerning the development of dental care of children, opinions differed widely: 46% of those questioned spoke of an increase in the incidence of caries during the past 5 years and 44% reported no change. Furthermore, dentists hold different views on the treatment of the primary dentition. There was no consensus of opinion about the necessity of treating caries in young children and there was a comparable lack of agreement about how and when treatment should be given. The majority of dentists express a need for support in their practice (possibilities for referral, protocols, informational material) concerning routine oral examination, the preventive and/or curative treatment of (young) children.

[The restorative care index in children 1. Factors concerning the child]. / De restauratieve verzorgingsgraad bij de jeugd 1. Patiëntgebonden factoren.

In 2007 a study was undertaken of the restorative care index of the teeth of children under the age of 18. The aim of this study was to gain insight into the factors associated with the restorative care index in children. Factors investigated were (post-) brushing, inspection frequency, sweets-consumption frequency, socio-economic status and treatment or lack thereof by a general practitioner or dentist who works in a clinic for child health care. This study made use of statistics assembled for an earlier study of children formerly covered by public health insurance in the municipality of The Hague and research carried out at child dental clinics. Socio-economic status and the level of oral care were correlated with dental quality. No patient-bound factors were significantly correlated with the level of care. There was however a positive correlation between the'type' of dentist (family dentist or dentist associated with a clinic for child dental care) and the chance of curative treatment (in the case of developing caries).

A longitudinal study of tooth erosion in adolescents.

Incidence studies on tooth erosion among adolescents are scarce. This longitudinal study aimed at estimating the prevalence, incidence, progression, and distribution of erosion in young adolescents over a 1.5-year period. Erosion at baseline was present in 32.2% of the 622 children (mean age, 11.9 +/- 0.9 yrs) and increased to 42.8% over 1.5 yrs. The prevalence of deep enamel or dentin erosion increased from 1.8% to 13.3%. It was hypothesized that more boys will suffer from erosion than girls. At baseline, no difference was found (p = 0.139), whereas 1.5 yrs later, more boys showed erosion than girls (p = 0.026). Of the erosion-free children, 24.2% developed erosion. Progression of erosion in terms of lesion depth and/or in number of lesions was 61.0% and was found more frequently in boys than in girls (p = 0.034). The distribution of erosion showed a predominance of occlusal surfaces of molars, especially the mesiobuccal cusp top, and palatal surfaces of upper anterior teeth.

Can caries fissures be sealed as adequately as sound fissures?

Sealing caries fissures is considered an appropriate treatment option for arresting the caries process. However, little information is available regarding the sealing of occlusal cavitated dentin lesions. The hypothesis tested in this in vitro study was that no difference in microleakage and sealant penetration depth exists between cavitated and sound sealed fissures when a resin is used. Eighty molars, each with an occlusal cavitated dentin lesion, were treated according to 5 experimental protocols and compared with a control group of sealed sound molars. In the experimental groups, fissure sealants were placed with and without an adhesive, and in various ways. All teeth were sectioned, and microleakage and sealant penetration into the fissure were evaluated. Sealed caries fissures showed significantly more microleakage and insufficient sealant penetration depth than sound fissures. Neither the use of an adhesive nor its intermediate curing influenced the microleakage score and the penetration ability of sealants.

Microleakage and sealant penetration in contaminated carious fissures.

OBJECTIVES: The aim of the present in vitro study was to evaluate the effect of an adhesive system on microleakage and sealant penetration depth in carious fissures after different surface contamination circumstances. METHODS: Extracted third molars (n=128) with small occlusal cavitated carious lesions were randomly divided into eight experimental groups and sealed under four different surface conditions. 1, Dry conditions; 2, water contamination; 3, saliva contamination; 4, saliva contamination and air-drying. Two sealant protocols were applied, one using a fissure sealant (Teethmate F) and one using an additional adhesive system (SA primer and Photo Bond). The control group consisted of sound third molars (n=16), that were sealed under dry conditions. After thermocycling (n=500 cycles), teeth were immersed in 1% methylene blue for 24h, sectioned and digitally photographed. Microleakage was evaluated on a three-point rating scale and analysed using a Chi-square test. Additionally, the presence of caries and incomplete sealant penetration was scored from photographs and analysed using logistic regression. RESULTS: A statistical significant difference regarding microleakage scores was present between sealed carious and sealed sound fissures. The use of an adhesive system in case of water contamination significantly reduced microleakage (p<0.05). With regard to sealant penetration depth, there were significant differences present for carious sealed fissures, use of an adhesive system prior to sealing, and water and saliva contamination. CONCLUSIONS: Use of an adhesive system improved the effectiveness of sealants placed after water contamination in carious fissures. However, sound fissures showed less microleakage and better penetration abilities than carious fissures.

[Prevalence of caries and dental erosion among school children in The Hague from 1996-2005]. / Prevalentie van tandcariës en tanderosie bij Haagse schoolkinderen in de periode 1996-2005.

In 2005 a dental survey of the prevalence of caries among 6- and 12-year-old schoolchildren in The Hague was carried out. In the case of the 12-year-olds, the prevalence of dental erosion was also studied. The sample consisted of 814 students in twelve primary schools in The Hague. The results reveal that since the previous study, in 2002, the trend in the direction of an increasing percentage of children with deciduous caries-free teeth and permanent caries-free teeth had continued. In the case of the children who were not caries-free, it was noticeable that, in general, the number of new dental caries (dmfs- and DMFS-score) had not changed in the period 1996-2005, while the number of restorations among the 6- and 12-year olds had decreased. The mean restorative index in the deciduous dentition of 6-year-olds decreased from approximately 40% in 1996 to approximately 20% in 2005; with respect to permanant dentition among 12-year-olds, the percentage decreased from more than 90% to 60%. The percentage of 12-year-olds with dental erosion in 2005 remained unchanged as compared with 2002: 24%. The research revealed that there was no increase in dental caries or dental erosion among the 6- and 12-year-old school children in The Hague.

Caries-inhibiting effect of chlorhexidine varnish in pits and fissures.

Evidence regarding the caries-inhibiting effect of chlorhexidine varnish is inconclusive. This study investigated the caries-inhibiting effect of the varnish EC40 on pits and fissures of first permanent molars. A two-year randomized controlled trial was carried out among 461 six- to seven-year-old children. In a split-mouth design, one group of molars received EC40 at baseline, 6, 12, and 18 months, and another group at baseline, 3, 12, and 15 months. Control molars did not receive EC40. Adherence to the treatment protocol was good. The dropout rate was 17%. Blinded examiners performed dental examinations. The caries-inhibiting effects of the two EC40 application schemes were comparable. The prevented fraction of caries was 25% (95%CI, 1%, 49%, p = 0.04) after 2 years and 9% (95%CI, -11%, 29%, p = 0.20) one year after termination of the trial, suggesting a short-term benefit from the use of EC40. The efficiency of EC40 is questionable in low-caries-incidence child populations.

Caries prevention by professional fluoride gel application on enamel and dentinal lesions in low-caries children.

In a double-blind randomized controlled clinical trial, the caries-reducing effect of semi-annually applied fluoride gel in a low-caries child population initially aged 4.5-6.5 years (n = 773) has been investigated. Secondary analyses of the data were performed to study the caries reduction including non-cavitated lesions. The treatment effect of fluoride gel was calculated as preventive fraction (PF). When enamel lesions were included in DFS count (D(2) grade), the PF was 22% as compared to 26% counting dentinal lesions. The PFs showed that the mean effect of professionally applied fluoride gel was highest (71%) for D(3)S in the permanent dentition and lowest for d(3)s in the primary dentition (5%). The PFs for approximal and buccal and lingual surfaces of the permanent dentition significantly decreased from 80 to 25% and from 60 to 37% when enamel lesions (D(2)S) were included. With the exception of the buccal and lingual surfaces, in the primary dentition the PFs varied slightly when enamel lesions were included. Inclusion of non-cavitated lesions in the treatment effect statistics did not change the former conclusion that the treatment effect of fluoride gel application on dental caries reduction in a low-caries child population was considered not clinically relevant.

Professionally applied fluoride gel in low-caries 10.5-year-olds.

The question has been raised whether low-caries children regularly using fluoride toothpaste will benefit from the professional application of additional fluoride gel. To investigate the caries-reducing effect of semi-annually-applied neutral 1% sodium fluoride gel, we carried out a double-blind randomized controlled clinical trial (n = 594) in a child population, initially aged 9.5-11.5 years, with baseline caries experience of D3MFS = 0 (decayed, missing, and filled tooth surfaces of permanent teeth). The mean number of tooth surfaces saved from caries development by fluoride gel application after 4 years was 0.2 D3MFS (SE = 0.17). The preventive fraction (PF) showed a mean relative effect of professionally applied fluoride gel of 18%. The cariostatic effect of the fluoride gel on pits and fissures would have been influenced by the sealant strategy in the study. Professionally applied fluoride gel showed no statistically significant effect on mean D3MFS score in low-caries 9.5- to 11.5-year-olds.