The use of aesthetic paediatric full coverage restorations among paediatric dental practitioners: an international survey

Despite the recent growing evidence in support of prefabricated zirconia crown use as a successful option in managing grossly carious anterior and posterior primary teeth, the use of such crowns remains controversial within the paediatric dental profession. This study aims to assess the use of aesthetic full coverage paediatric restorations among paediatric dentists worldwide, with emphasis on aesthetic prefabricated zirconia crowns. This was an online cross-sectional survey questionnaire study comprising of 38 multiple-choice questions disseminated worldwide through the contact lists of national, regional and international paediatric dental organisations and social media platforms. The survey was completed by 556 respondents thus achieving power, with 391 (70.3%) females and 165 (29.7%) males. The respondents were from 55 different countries spread across six continents. The use of aesthetic full coverage restorations was reported by 80% (n = 444) of the respondents. For restoring anterior teeth, participants mainly used either composite strip crowns (94.4%, n = 419) or zirconia crowns (73.6%, n = 327), while those who used aesthetic crowns for restoring posterior teeth mainly used zirconia crowns (68.2%, n = 303). Within the limitations of this study, the results have shown a wide use of full coverage aesthetic restorations, including the use of zirconia crowns, of primary teeth within this international sample of practicing dentists.

Hall technique versus conventional preformed metal crowns: can paediatric dentists tell the difference on radiographs?

PURPOSE

Hall technique (HT) preformed metal crowns (PMCs) are allegedly oversized compared to conventional (C) PMCs. To investigate paediatric dentists' (PDs) perception of HT-PMCs and perception/ability to identify HT or C-PMCs on bitewings radiographs.

METHODS

An online cross-sectional questionnaire including ten bitewings (five of each of HT/CPMCs) was sent to PDs across the globe. A PMC type score (from '10') was calculated. T test, Pearson's and Fischer's Chi-square, and Odd Ratios (OR) (p < 0.05).

RESULTS

A total of 476 PDs from around the world responded. Most (97%) used PMCs in their practice. Most (98.7%) knew of, and 79% used HT-PMCs. A clear opinion shift, towards supporting HT, over time was noted (OR 11.154 [95% confidence interval (CI) 6.006-20.715]. A majority (67%) thought that HT/C-PMCs were similar radiographically. Only five PMCs were identified correctly [mean score 4.9 (± 1.73)]. A minority who thought that HT/C-PMCs were dissimilar scored higher than those who thought they were similar (5.31 ± 1.22; 4.68 ± 1.9, respectively, p < 0.00001). Nobody identified all ten PMCs. HT-PMCs were 4.63 times more identifiable than C-PMCs [(OR 24.857 CI 15.059-41.028) and (OR 5.361 CI 3.089-9.304)] for HT-PMCs and CP-MCs, respectively (p < 0.0001).

CONCLUSIONS

PDs identified the PMC type in half of the bitewings. They perceived no clear radiographic difference between HT-PMCs and C-PMCs, but their chance of recognizing HT-PMCs was five times higher than C-PMCs. HT-PMC support was high.

Silver diamine fluoride: A stem cell cytotoxicity and dentin growth factor release in-vitro study

AIM

To investigate the effect of 38% SDF and its serial dilutions on the Stem cells from Human Exfoliated Deciduous teeth (SHED) and its ability to release growth factors from deciduous dentine.

METHODS

The viability of SHED post-exposure to 38%, 3.8%, 0.38%, 0.038%, and 0.0038% SDF were assessed at 2, 5, and 7 days using the CyQuant assay, and results were validated using the MTT assay. The osteogenic differentiation of the cells was also investigated post-exposure to 0.0038% SDF. The release of the growth factors; TGF-β1, FGF-b, BMP-2, and VEGF from deciduous dentin discs exposed to 38% SDF, 0.0038% SDF, Ca(OH)2, MTA, and 17% EDTA were examined using ELISA. Statistical analysis was performed using means and standard deviations (p < 0.05). Two-way ANOVA compared the means of more than two groups with Tukey's multiple comparison test. The unpaired t-test was also used to compare the differences between the two data sets.

CONCLUSION

38% SDF released dentinogenic growth factors from dentin discs, potentially explaining its role in reactionary dentinogenesis. Moreover, 0.0038% SDF resulted in a non-cytotoxic concentration that enhanced cellular proliferation and released bioactive molecules from dentin comparable to the 38% concentration. After further investigations, the 0.0038% dilution of SDF could present itself as a clinical concentration.

Sugar content in infant formula: Accuracy of labeling and conformity to guidelines

BACKGROUND

Infant formulae are a primary source of nutrition during the first years of life, to which sugars are frequently added. This may contribute to adverse dental health problems if consumed excessively when coupled with prolonged and nocturnal feeding habits.

AIM

To assess the amount and type of dietary sugars in commercially available infant formulae in the UAE.

DESIGN

Sucrose, glucose, and fructose were measured in 71 different brands of commercially available infant formulae for retail sale in the UAE. Analysis was performed using high-performance liquid chromatography with refractive index detection. Sugar values were compared with the reported levels on the nutritional labels. A comparison between findings, product labels, and international standards for infant formulae was performed.

RESULTS

Of the 71 samples, 23 had detectable sugar levels, varying between sucrose, glucose, and fructose. Ten samples were found to have sugars contributing to more than 5% of total energy intake ranging between 5.68% and 27.06%. All infant formula packages had carbohydrate levels mentioned on the labels, but very few mentioned the added sugar content.

CONCLUSIONS

Many infant formula products tested contained sugars that exceeded the standard recommended intake. Tighter regulations that monitor the amount of sugar in infant formulae and guidelines for comprehensive labeling systems are required.

Enablers and barriers associated with high MMR uptake among the Finnish Somali population

Introduction

In Finland, the Somali-speaking community is the fourth largest migrant group after Russian, Estonian, and Arabic-speaking communities. Finland is home to 21,000 Somali-speaking individuals, with around 70 % of them living in the capital region. Even though vaccine uptake in most ethnic minority communities is usually lower, MMR coverage in Finnish Somali children is partly higher than that of ethnic Finns.

Methods

We interviewed 30 Somali-origin mothers living in the capital region of Finland in terms of childhood vaccination acceptance, and in specific, issues affecting their children's MMR vaccine uptake. All interviews were conducted by a Somali researcher either in Somali or Finnish language. The interviews were recorded, transcribed, translated, and analysed using thematic analysis of the transcripts. To understand the enablers presented by the health care system in Finland, 10-15 public health nurses working in maternal and child health clinics in the capital region will be interviewed.

Results and discussion

Preliminary results show that trust in the health care system is the main enabler of high MMR vaccine coverage in the Somali population - even when mother's knowledge of the vaccine was very limited. In terms of information sources, mothers indicated that they ask, and trust maternal and child health clinics in all vaccine-related information- often more than any other source, including the internet.

Conclusions

This study enhances our understanding of system level enablers in the Finnish Somali community regarding MMR vaccination. The results of this study are applicable to improve vaccine uptake in other underserved minority communities throughout Europe.

Characteristics of Pediatric Dental Treatment Provided under General Anesthesia in Dubai, United Arab Emirates: A Retrospective Analysis

Background

Dental general anesthesia (DGA) is a widely utilized technique in pediatric dentistry and is indicated for a variety of cases such as very young children and children with special healthcare needs (SHCN). In the United Arab Emirates (UAE), there is a paucity of studies relating to this subject.

Objective

To analyze the characteristics of DGA treatment in special healthcare needs and healthy children in the only postgraduate dental hospital in Dubai, UAE.

Materials and Methods

A retrospective analysis was conducted on the electronic records of all Dubai Dental Hospital (DDH) pediatric patients who underwent DGA in the period between January 1^st, 2016, and 29^th of February 2020.

Results

The study population consisted of 98 children. A total of 26 children had a medical condition and were categorized as SHCN. The most common justification for DGA was dental caries and a lack of cooperation due to young age. SHCN patients received significantly more preventive measures and significantly fewer pulp therapies than healthy patients.

Conclusion

We found that the services provided under DGA for healthy pediatric patients differ from those provided to SHCN patients. Frequently missing recall appointments following DGA increased the likelihood of the need for further restorative dental treatment. These results highlight the importance of robust prevention and follow-up programs for children treated under GA.

Trajectories of psychiatric care in an innovative outpatient program designed for transitional age youth (16 to 24 years old) in French-speaking Belgium: results of a retrospective study

Introduction

Transitional age youth (TAY), from 16 to 24 years old, are a particularly at-risk population in mental health. They have specific needs, not currently covered between child and adolescent mental health services (CAMHS) and adult mental health services (AMHS), mainly because of existing barriers.

Objectives

This retrospective study was carried out to describe sociodemographic and clinical characteristics of 243 patients who attended a new TAY-tailored outpatient psychiatric program.

Methods

Outcomes related to trajectories of psychiatric care were analysed, such as leading symptom, consultation’s referral and requester, and final orientation.

Results

The sample was mainly composed by female; the average age was 18.7 (± 2.0) years. Leading symptoms were divided into three dimensions: internalizing (67.5%), externalizing (21.8%) and psychotic (10.7%). Leading symptom differed according to sex (p<0.001), with internalizing symptoms more frequent in women, externalizing and psychotic symptoms more frequent in men. Patients presenting psychotic symptoms were significantly older than both those with internalizing (p=0.016) and externalizing symptoms (p=0.008). After first assessment, 81.5% of youth were followed-up in our specific outpatient program, without any difference according to sex (p=0.081) or leading symptom (p=0.092). Overall and final psychiatric orientation are showed in the flowchart.

Conclusions

This TAY-tailored psychiatric outpatient program represents an innovative contribution to reinforce CAMHS-AMHS interface in French-speaking Belgium. This study enlightens the importance to enhance clinical expertise in youth mental health. Classical boundaries, determined by artificial variables such as age or type of psychopathology, do not seem to be efficient criteria to achieve a good quality psychiatric evaluation and continuity of care in TAY.

Disclosure

The authors declare no potential conflicts of interest. The study was carried out as part of the University Chair “Psychiatry in Transition in a World in Transition” (Université Libre de Bruxelles - ULB) with the support of Julie Renson Fund, the Queen Fa

What is the effect of preterm birth on permanent tooth crown dimensions? A systematic review and meta-analysis

BACKGROUND

The permanent tooth formation process may be disrupted in preterm infants with potential discrepancies in size and subsequent occlusal disturbances.

OBJECTIVE

To systematically analyse and quantitively synthesize the available evidence regarding the impact of preterm birth on permanent tooth crown dimensions.

SEARCH METHODS

Unrestricted searches in 6 databases and manual searching of the reference lists in relevant studies were performed up to March 2021 (Medline via PubMed, CENTRAL, Cochrane Database of Systematic Reviews, Scopus, Web of Science, ProQuest Dissertations and Theses Global).

SELECTION CRITERIA

Observational studies investigating permanent tooth crown dimensions in preterm and control full-term born individuals.

DATA COLLECTION AND ANALYSIS

Following study retrieval and selection, relevant data were extracted, and the Newcastle-Ottawa scale was used to assess the selection, comparability, and outcome domains. Exploratory synthesis and meta-regression were carried out using the random effects model.

RESULTS

Three studies were located from the initially retrieved records and the assessments with the Newcastle-Ottawa scale identified issues regarding the selection and comparability domains. Overall, the mesiodistal and the buccolingual dimensions of the permanent teeth in both dental arches tended to be smaller in children born prematurely than full term children. Subgroup analyses showed statistically significant differences for the extremely preterm to control group comparisons for the incisors and the first molars. Meta-regression showed a modificatory effect of gestational age and racial background but not of birth weight and gender on tooth size. The quality of available evidence was rated at best as moderate.

CONCLUSIONS

Premature birth could potentially be associated with reduced tooth-crown dimensions in some permanent teeth especially in children born extremely preterm. Although the results from these observational studies should be approached with caution until more information becomes available, the possible clinical implications in terms of diagnosis and treatment planning should be considered.

REGISTRATION

PROSPERO (CRD42020182243).

How Do Schoolchildren View Other Children Who Have Discolored Teeth?

Objectives:

Facial look and expression affect how people are viewed by others. This study aimed to evaluate how schoolchildren in the Emirate of Sharjah, United Arab Emirates view their peers who have discolored teeth.

Materials and Methods:

A cross-sectional study using randomized cluster sampling of Sharjah public schools was conducted. A previously developed and validated social attribute questionnaire was utilized to determine children’s dental appearance-related judgments. Children aged 11–14 years were given photographs of subjects either with discolored teeth or without, and they were asked to rate them using six positive and five negative signifiers. The total attribute score (TAS) ranged from 11 (most negative) to 44 (most positive). A linear regression analysis and t-tests were performed to determine the effects of gender and age in mean TAS.

Results:

TAS was significantly lower among discolored teeth photographs when compared with photographs without teeth discoloration (P = 0.004). TAS was found to be significantly higher with increased age (P = 0.035), but gender had no significant effect.

Conclusion:

Teeth discoloration resulted in more negative social judgment between Sharjah schoolchildren and their peers.

COVID-19 outbreak at a reception centre for asylum seekers in Espoo, Finland

Background shared accommodation may increase the risk of SARS-CoV-2 transmission. In April 2020, an increasing number of asylum seekers at a reception centre in Espoo, Finland presented with COVID-19 despite earlier implementation of preventive measures. We decided to screen the entire population of the centre for SARS-CoV-2.

Methods we offered nasopharyngeal swab collection and SARS-CoV-2 real-time polymerase chain reaction (RT-PCR) analysis to the centre's clients. Symptoms were recorded at the time of diagnostic sample collection using electronic forms and followed up for two weeks through phone interviews and a review of medical records.

Findings 260 clients were screened. Of them, 96 (37%) were found positive for SARS-CoV-2 and isolated. The high attack rate prompted the local public health authority to set the other clients in quarantine for 14 days to prevent further spread. Of the positive cases, 61 (64%) reported having had symptoms at the time of the screening or one week prior. Of the 35 initially asymptomatic individuals, 12 developed symptoms during follow-up, while 23 (or 18% of all screened SARS-CoV-2 positive clients) remained asymptomatic. No widespread transmission of COVID-19 was detected after the quarantine was lifted.

Interpretation in this large COVID-19 outbreak, voluntary mass screening provided valuable information about its extent and helped guide the public health response. Comprehensive quarantine and isolation measures were likely instrumental in containing the outbreak.

Funding Finnish Institution for Health and Welfare, Finnish Immigration Agency, City of Espoo

Perceived Preparedness of Dental Academic Institutions to Cope with the COVID-19 Pandemic: A Multi-Country Survey

Dental academic institutions are affected by COVID-19. We assessed the perceived COVID-19 preparedness of these institutions and the characteristics of institutions with greater perceived preparedness. An international cross-sectional survey of dental academics was conducted from March to August 2020 to assess academics’ and institutional attributes, perceived preparedness, and availability of infection prevention and control (IPC) equipment. Principal component analysis (PCA) identified perceived preparedness components. Multilevel linear regression analysis assessed the association between perceived preparedness and fixed effect factors (academics’ and institutions’ attributes) with countries as random effect variable. Of the 1820 dental academics from 28 countries, 78.4% worked in public institutions and 75.2% reported temporary closure. PCA showed five components: clinic apparel, measures before and after patient care, institutional policies, and availability of IPC equipment. Significantly less perceived preparedness was reported in lower-middle income (LMICs) (B = −1.31, p = 0.006) and upper-middle income (UMICs) (B = −0.98, p = 0.02) countries than in high-income countries (HICs), in teaching only (B = −0.55, p < 0.0001) and in research only (B = −1.22, p = 0.003) than teaching and research institutions and in institutions receiving ≤100 patients daily than those receiving >100 patients (B = −0.38, p < 0.0001). More perceived preparedness was reported by academics with administrative roles (B = 0.59, p < 0.0001). Academics from low-income countries (LICs) and LMICs reported less availability of clinic apparel, IPC equipment, measures before patient care, and institutional policies but more measures during patient care. There was greater perceived preparedness in HICs and institutions with greater involvement in teaching, research, and patient care.

A 24-month retrospective study of preformed metal crowns: the Hall technique versus the conventional preparation method

PURPOSE

Conventional and Hall Technique (HT) Preformed Metal Crowns (PMCs) are used for treatment of carious primary molars. The aim was to evaluate the clinical and radiographic success of conventional and HT PMCs in a postgraduate dental setting.

METHODS

A retrospective study using patients' electronic case-notes and radiographic images of carious primary molars treated with either conventional or HT PMCs was conducted to assess clinical and radiographic success/failure. A Kaplan-Meier curve was used to assess PMC survival.

RESULTS

187 PMCs (110 HT and 77 conventional) in 65 children (34 females and 31 males) at 6, 12, 18 and 24 months were assessed. At 24 months, the success rates of conventional and HT PMCs were 97.6% and 93.5%, respectively. Two HT (perforated/abscessed) and four conventional (abscessed) PMCs failures occurred. There was no significant difference in success/failure (p = 0.362) at 12 months, but the HT was more successful at 24 months (p = 0.002) with similar survival times for both methods.

CONCLUSION

HT and conventionally placed PMCs, when placed in a postgraduate paediatric dentistry setting, were clinically and radiographically very successful at 6, 12, 18 and 24 months post operatively with a slightly higher success of the HT at 24 months.

Children's dental anxiety (self and proxy reported) and its association with dental behaviour in a postgraduate dental hospital

PURPOSE

Child dental anxiety (CDA) and uncooperative dental behaviour are common. We aimed to assess the prevalence of CDA (self- and proxy- reported) in the United Arab Emirates (UAE) children related to their dental behaviour.

METHODS

Data were collected from 312 questionnaires obtained from 156 parent/child (mean age 9.95 ± 2.17 years) pairs attending a postgraduate dental hospital. Demographics, self/proxy- reported CDA scores via a six-question, five-point Likert scale, of the Modified CDA Scale-faces version (MCDAS-f: where ≥ 19 was severe CDA) and Frankl Behaviour Rating Scale (FBRS) scores were compared and analysed. Chi-square test, Pearson's correlation, Kappa- coefficient, one-way ANOVA and independent t test statistical analysis were used (p < 0.05).

RESULTS

The prevalence of self and proxy severe CDA was 22.4% (n = 35) and 33.3% (n = 52) respectively, with 9% (n = 14) being dentally- uncooperative. In both groups, extractions caused the highest CDA followed by injections and fillings (p < 0.001). The mean scores for self-reported/proxy-reported CDA were 15.02 (± 4.90)/15.70 (± 6.07) respectively. There was a positive linear correlation between self- and proxy- reported CDA scores and a negative linear correlation between self/proxy- reported CDA scores and the FBRS (p < 0.001). Self/proxy concordance of severe anxiety/none-to-moderate- anxiety was fair (68.6%, kappa = 0.23, p = 0.003). Both self/FBRS and proxy/FBRS concordance of severe anxiety/none-to-moderate- anxiety/behaviour was fair (78.8%, kappa = 0.23, p = 0.001) and (71.8%, kappa = 0.22, p < 0.001) respectively.

CONCLUSIONS

Considering the limitations of the present study in a UAE child population sample, the prevalence of CDA from extractions, injections and fillings was 22.4% (self- reported) and 33% (proxy reported). There was fair agreement between child- self and parent- proxy- reported CDA. Increased CDA led to uncooperative dental behaviour.

Knowledge of dental faculty in gulf cooperation council states of multiple-choice questions' item writing flaws

Multiple-Choice Questions provide an objective cost/time effective assessment. Deviation from appropriate question writing structural guidelines will most probably result in commonly ignored multiple-choice questions writing flaws, influencing the ability of the assessment to measure students' cognitive levels thereby seriously affecting students' academic performance outcome measures. To gauge the knowledge of multiple-choice question items writing flaws in dental faculty working at colleges in Gulf Cooperation Council (GCC) countries. A cross-sectional short online Survey Monkey^TM multiple-choice questions-based questionnaire was disseminated to dental faculty working in GCC countries during the academic year 2018/2019. The questionnaire included five test incorrect (flawed) multiple-choice questions and one correct control question. The participants were asked to identify flawed multiple-choice question items from the known 14 items writing flaws. Out of a total of 460 faculty, 216 respondents completed the questionnaires, 132 (61.1%) were from Saudi Arabia, while numbers of participants from United Arab Emirates, Kuwait and Oman were 59 (27.3), 14 (6.5%) and 11 (5.1%) respectively. Majority of participants were male (n = 141, 65.9%) compared to 73 females (34.1%). Eighty percent of the participants possessed more than five years of teaching experience. Assistant professors constituted the majority (43.3%) of the academic positions participating in this study. The overall fail rate ranged from 76.3% to 98.1% and almost 2/3^rds of the participants were unable to identify one or more of the flawed item(s). No significant association was observed between the demographics (age, region, academic position and specialty) and knowledge except that of participant's gender (p < 0.009). GCC dental faculty demonstrated below average knowledge of multiple-choice question items writing flaws. Training and workshops are needed to ensure substantial exposure to proper multiple-choice question items construction standards.

Knowledge of dental academics about the COVID-19 pandemic: a multi-country online survey

BACKGROUND

COVID-19 is a global pandemic affecting all aspects of life in all countries. We assessed COVID-19 knowledge and associated factors among dental academics in 26 countries.

METHODS

We invited dental academics to participate in a cross-sectional, multi-country, online survey from March to April 2020. The survey collected data on knowledge of COVID-19 regarding the mode of transmission, symptoms, diagnosis, treatment, protection, and dental treatment precautions as well as participants' background variables. Multilevel linear models were used to assess the association between dental academics' knowledge of COVID-19 and individual level (personal and professional) and country-level (number of COVID-19 cases/ million population) factors accounting for random variation among countries.

RESULTS

Two thousand forty-five academics participated in the survey (response rate 14.3%, with 54.7% female and 67% younger than 46 years of age). The mean (SD) knowledge percent score was 73.2 (11.2) %, and the score of knowledge of symptoms was significantly lower than the score of knowledge of diagnostic methods (53.1 and 85.4%, P <  0.0001). Knowledge score was significantly higher among those living with a partner/spouse than among those living alone (regression coefficient (B) = 0.48); higher among those with PhD degrees than among those with Bachelor of Dental Science degrees (B = 0.48); higher among those seeing 21 to 30 patients daily than among those seeing no patients (B = 0.65); and higher among those from countries with a higher number of COVID-19 cases/million population (B = 0.0007).

CONCLUSIONS

Dental academics had poorer knowledge of COVID-19 symptoms than of COVID-19 diagnostic methods. Living arrangements, academic degrees, patient load, and magnitude of the epidemic in the country were associated with COVD-19 knowledge among dental academics. Training of dental academics on COVID-19 can be designed using these findings to recruit those with the greatest need.

Enamel defects and caries prevalence in preterm children aged 5-10 years in Dubai

Background: Enamel defects (EDs) are commonly reported dental findings in preterm/low birthweight children. EDs potentially increase caries susceptibility.Aim: To assess the prevalence of EDs and dental caries in a group of preterm children (aged 5-10 years) in Dubai, United Arab Emirates (UAE).Methodology: A retrospective cohort study of medical records of 62 preterm children (mean age 8.1 ± 1.54) and 62 full-term children (mean age 8.1 ± 1.73) of both genders born in a UAE children's hospital were studied. These children were dentally assessed for EDs and caries by a calibrated examiner.Results: EDs were 4.34 times more prevalent among preterm children [odd ratio (OR) = 4.338, CI 95% [2.010-9.366]. The prevalence of EDs in the pre-term group was 58.15%, significantly higher (P < 0.01) than the full-term control group (24.2%). Birth weight, intubation and type of delivery were statistically significant factors contributing to EDs. In the primary dentition, the mean dmft was 4.61 ± 4.30, while in the permanent dentition DMFT was 0.38 ± 0.99. There was a statistically significant difference in permanent teeth caries experience amongst pre-term children compared to the full-term control as measured by DMFT (P = 0.008).Conclusion: EDs and dental caries in permanent dentition in the pre-term group were significantly higher than the full-term group.

Behavior change due to COVID-19 among dental academics-The theory of planned behavior: Stresses, worries, training, and pandemic severity

OBJECTIVE

COVID-19 pandemic led to major life changes. We assessed the psychological impact of COVID-19 on dental academics globally and on changes in their behaviors.

METHODS

We invited dental academics to complete a cross-sectional, online survey from March to May 2020. The survey was based on the Theory of Planned Behavior (TPB). The survey collected data on participants' stress levels (using the Impact of Event Scale), attitude (fears, and worries because of COVID-19 extracted by Principal Component Analysis (PCA), perceived control (resulting from training on public health emergencies), norms (country-level COVID-19 fatality rate), and personal and professional backgrounds. We used multilevel regression models to assess the association between the study outcome variables (frequent handwashing and avoidance of crowded places) and explanatory variables (stress, attitude, perceived control and norms).

RESULTS

1862 academics from 28 countries participated in the survey (response rate = 11.3%). Of those, 53.4% were female, 32.9% were <46 years old and 9.9% had severe stress. PCA extracted three main factors: fear of infection, worries because of professional responsibilities, and worries because of restricted mobility. These factors had significant dose-dependent association with stress and were significantly associated with more frequent handwashing by dental academics (B = 0.56, 0.33, and 0.34) and avoiding crowded places (B = 0.55, 0.30, and 0.28). Low country fatality rates were significantly associated with more handwashing (B = -2.82) and avoiding crowded places (B = -6.61). Training on public health emergencies was not significantly associated with behavior change (B = -0.01 and -0.11).

CONCLUSIONS

COVID-19 had a considerable psychological impact on dental academics. There was a direct, dose-dependent association between change in behaviors and worries but no association between these changes and training on public health emergencies. More change in behaviors was associated with lower country COVID-19 fatality rates. Fears and stresses were associated with greater adoption of preventive measures against the pandemic.

The use of behaviour management techniques amongst paediatric dentists working in the Arabian region: a cross-sectional survey study

Purpose

The purposes of this study were to investigate paediatric dental practitioners’ training and confidence in using dental behaviour management techniques in the Arabian region and to assess the factors influencing the application of advanced behaviour management techniques. Methods: An online questionnaire was distributed to paediatric dental practitioners in the Arabian region. Data were analysed using descriptive statistics and Pearson Chi Square.

Results

A total of 113 responses were obtained. Of these, the majority were from Egypt (45%, n = 51). Just over half of the respondents were registered as specialists at the country where they were practicing paediatric dentistry (53%, n = 60). The use of behaviour management techniques varied amongst participants with tell-show-do (95%, n = 107) and positive reinforcement (89%, n = 101) being the most routinely used techniques. The majority of participants reported using voice control (83%) and parental separation (68%) techniques. Hand over mouth exercise (HOME) was only used by 24% (n = 27) of participants, whilst just over half of the participants, 53%, reported using protective stabilisation. A significant association was shown between country of practice, country of obtaining paediatric dental training, speciality status and the use of advanced behaviour management techniques, whilst confidence in using HOME and sedation were associated with work setting and country of practice, respectively.

Conclusion

The use of advanced behaviour management techniques was found to be high amongst respondents in the Arabian region. The lack of training in using these techniques, however, is of concern. Further assessment of the factors affecting the use of and confidence in applying advanced behaviour management techniques in the Arabian region is needed.

Hall technique crowns and children's masseter muscle activity: A surface electromyography pilot study

BACKGROUND

Hall technique crowns (HTCs) alter the occlusion temporarily, potentially affecting jaw muscles, particularly the masseter - the primary jaw-closing muscle.

AIM

To assess masseter muscle activity (MMA) in children treated with a unilateral HTC.

DESIGN

In 12 children treated with a single HTC, bilateral MMA was recorded with surface electromyography (sEMG) for ten cycles of Rest Position (RP) and Maximum Voluntary Clenching (MVC) over 20 seconds immediately pre-HTC cementation (P_base ), immediately post-HTC cementation (P_immed ), at 2 weeks post-HTC cementation (P_2w ) and at 6 weeks post-HTC cementation (P_6w ). t test, ANOVA and post hoc statistics were used (P < .05).

RESULTS

As expected, MMA was low at rest and increased during maximal jaw clenching (P < .0001). MMA (mean ± SD) increased significantly (P < .001) between RP and MVC at: P_base [from 1.60 μV·s (±0.96) to 5.40(±2.30)]; P_immed [1.57(±1.15) to 3.75(±1.87)]; P_2w [1.39(±0.54) to 5.54(±1.45)] and finally P_6w [1.46(±0.56) to 6.45(±2.56)]. Rest MMA at P_base , P_immed , P_2w and P_6w remained unchanged (P = .18) whereas P_base clench MMA reduced by a third at P_immed (P < .001), returned to and exceeded baseline levels at P_2w (P = .822) and P_6w (P < .001), respectively.

CONCLUSIONS

This pilot study showed that Hall technique crowns may affect masseter muscle activity in children. Clench MMA was reduced immediately post-treatment but returned to and later exceeded baseline levels at 2 and 6 weeks, respectively. Rest MMA remained unchanged.

Dentists' knowledge of the guidelines of traumatic dental injuries in the United Arab Emirates

AIM

This study aimed to assess general dental practitioners' (GDPs) knowledge within the United Arab Emirates (UAE) regarding the management of traumatic dental injuries (TDIs), and to compare their level of knowledge with that of paediatric dentists (PDs).

METHODS

Dentists were asked to complete a two-part questionnaire (seven questions covering demographic data and 13 questions about trauma cases scenarios) in electronic and paper format. A total of 296 returned questionnaires were analysed to identify GDPs' knowledge in managing TDIs, and to compare the score of GDPs' knowledge with that of PDs'.

RESULTS

Out of a total score of 13, the mean knowledge score (MKnS) for GDPs was 4.87±1.82 (only 37.5% of the 13 questions were answered correctly) while the MKnS of paediatric dentists was 5.56±1.47 (with 42.8% correct answers); both scores indicated poor knowledge and the difference was statistically significant (p=0.005).

CONCLUSION

There was poor knowledge of TDIs among the surveyed UAE GDPs as well as the PDs, although PDs scored higher, indicating the need for further training.

Evaluating the Quality of Multiple Choice Question in Paediatric Dentistry Postgraduate Examinations

Objectives

This study aimed to evaluate the quality of multiple choice question (MCQ) items in two postgraduate paediatric dentistry (PD) examinations by determining item writing flaws (IWFs), difficulty index (DI) and cognitive level.

Methods

This study was conducted at Mohamed Bin Rashid University of Medicine and Health Sciences, Dubai, UAE. Virtual platform-based summative versions of the general paediatric medicine (GPM) and prevention of oral diseases (POD) examinations administered during the second semester of the 2017–2018 academic year were used. Two PD faculty members independently reviewed each question to assess IWFs, DI and cognitive level.

Results

A total of 185 single best answer MCQs with 4–5 options were analysed. Most of the questions (81%) required information recall, with the remainder (19%) requiring higher levels of thinking and data explanation. The most common errors among IWFs were the use of “except” or “not” in the lead-in, tricky or unfocussed stems and opportunities for students to use convergence strategies. There were more IWFs in the GPM than the POD examination, but this was not statistically significant (P = 0.105). The MCQs in the GPM and POD examination were considered easy since the mean DIs (89.1% ± 8.9% and 76.5% ± 7.9%, respectively) were more than 70%.

Conclusion

Training is an essential element of adequate MCQ writing. A general comprehensive review of all programme’s MCQs is needed to emphasise the importance of avoiding IWFs. A faculty development programme is recommended to improve question-writing skills in order to align examinations with programme learning outcomes and enhance the ability to measure student competency through questions requiring higher level thinking.

A single-centre investigator-blinded randomised parallel group clinical trial to investigate the effect of probiotic strains Streptococcus salivarius M18 and Lactobacillus acidophilus on gingival health of paediatric patients undergoing treatment with fixed orthodontic appliances: study protocol

BACKGROUND

There is limited data on the beneficial effects of probiotics on the gingival health of patients undergoing treatment with fixed orthodontic appliances. This study aims to compare the effect of probiotic tablets combined with regular oral hygiene versus regular oral hygiene alone on gingival status in these patients. The effect of probiotic intake on plaque formation and salivary microbiome composition will be also assessed.

METHODS AND ANALYSIS

This is a 3 month single-centre, single blind (clinical and laboratory examiners), parallel group randomised controlled two arm superiority trial. Fifty paediatric patients attending the Postgraduate Orthodontic Clinic at the Hamdan Bin Mohammed College of Dental Medicine (HBMCDM), Mohammed Bin Rashid University of Medicine and Health Sciences (MBRU), Dubai, United Arab Emirates, who meet the eligibility criteria will be recruited. Block randomisation with 1:1 allocation and concealment of allocation will be carried out. The treatment group will receive probiotic tablets containing Streptococcus salivarius M18 and Lactobacillus acidophilus together with regular oral hygiene versus the control group on regular oral hygiene alone. Clinical examination and collection of saliva for microbiome assay will be carried out at baseline and end of study. Self-reporting by patients will be used to document acceptability and adverse effects. Statistically significant decrease in gingival bleeding on probing in the treatment group will be classified as primary outcome of treatment success. Statistically significant reduction in Plaque Index, Gingival Index and shift in the composition of the oral microbiome in favour of beneficial bacteria are secondary outcomes indicative of efficacy of probiotic intake.

ETHICS AND DISSEMINATION

Ethical approval for the study has been granted by the HBMCDM, MBRU, Institutional Review Board (Reference #: MBRU-IRB-2018-015). Study findings will be disseminated via publication in peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ISRCTN95085398.

A study protocol of a single-center investigator-blinded randomized parallel group study to investigate the effect of an acclimatization visit on children's behavior during inhalational sedation in a United Arab Emirates pediatric dentistry postgraduate setting as measured by the levels of salivary Alpha Amylase and Cortisol

INTRODUCTION

Inhalation sedation is a proven safe method for reducing children's dental anxiety and has been used worldwide for decades. There is controversy regarding the use of acclimatization or familiarization visits for dental sedation treatment pathways for children. This may increase acceptance to the treatment based on desensitization and acclimatization principles underpinning many behavior management techniques. This study aims to identify whether, an inhalation sedation acclimatization visit is effective in reducing the stress level in anxious children as measured by salivary Alpha Amylase and Cortisol levels.

METHODS

The study is a single-center, single blinded, parallel group 2 arm clinical trial. Children in need of inhalation sedation aged 5 to 15 years from September 2019 through March 2020 attending the Postgraduate Pediatric Clinic at the Hamdan Bin Mohammed College of Dental Medicine, in Dubai, will be allocated randomly and equally to either:At the initial visit a salivary sample will be collected at the beginning of the visit and the sedation need score will be recorded using the pediatric indicator of sedation need. Treatment for both groups will commence at the second visit. Salivary samples will be collected 15 minutes before the start of the treatment and 15 minutes after the conclusion of the treatment. The following outcomes will be recorded: completion of dental treatment, anxiety scores at baseline and after treatment using Frankl rating behavior scale and physiological anxiety related changes will be recorded using salivary Alpha Amylase and Cortisol levels. Mean changes of physiologic anxiety levels and corresponding 95% confidence intervals will be determined to compare the 2 treatments (sedation with familiarization and sedation without familiarization).

DISCUSSION

This is will be the first study to measure the effect of the acclimatization visit of nitrous oxide inhalation sedation on the level of physiological anxiety and the behavior of the pediatric patients during treatment.

Knowledge of Management of Traumatic Dental Injuries of Emergency Department Physicians and Residents in the United Arab Emirates

Purpose: To investigate knowledge of emergency department physicians and residents (ED-Drs) about management of traumatic dental injuries (TDI) in the United Arab Emirates (UAE).<br/> Methods: A cross sectional study of ED-Drs was conducted using a questionnaire and a score of TDI knowledge (TDI-K) was created (maximum of six). Statistical analysis was performed using chi-square, Fisher's exact, Mann-Whitney U, and Kruskal-Wallis tests, and significance was set as P <0.05.<br/> Results: One hundred fifty-five physicians participated, with one-third reporting they encountered TDI more than once a week. Sixty percent of ED-Drs had received TDI education, of which a significantly higher proportion (84.4 percent) were Western-trained (P =0.007). Consultants and specialists had the highest knowledge scores (P =0.001). ED-Drs with five to 10 years' experience scored significantly lower (3.07±1.65) than those with less than five years of experience (3.86±1.36) and those with more than 10 years of experience (3.83±1.36, P=0.034). Only 38.2 percent of general practitioners (GPs) were confident placing sutures intraorally, compared to 80.6 percent of the consultants and specialists and 57.1 percent of the residents.<br/> Conclusion: Overall knowledge of TDI and their management among ED-Drs across the UAE is inadequate. GPs had the lowest knowledge and confidence to manage TDI. (J Dent Child 2019;86(1):24-31)<br/> Received December 11, 2018; Last Revision January 11, 2019; Accepted January 11, 2019.

A systematic review and meta-analysis of primary teeth caries studies in Gulf Cooperation Council States

OBJECTIVES

The aim of the study was to evaluate the prevalence and severity of dental caries in pre-school children in the Gulf Cooperation Council (GCC) area.

METHODS

A search of literature was conducted to identify articles of dental caries in primary dentitions published during the period from January 1st, 1992 to June 30th, 2016. PubMed, Google Scholar search, and hand searching of journals was conducted to identify relevant articles. The search strategy employed both dental subject headings and free-text terms.

RESULTS

Out of a total of 193 studies that fit the initial inclusion criteria, 159 studies were further excluded. Only 34 studies were included in the systematic review and meta-analyses. The overall mean dmft in the primary teeth was 5.14 with prevalence of 80.9% in the GCC area. A high level of heterogeneity in the selected studies was found as demonstrated by Q-value of 2538.501 (df = 21) and I2 value of 99.17%. However, the funnel plots showed symmetrical shape at the bottom in both dmft and prevalence studies indicating absence of publication bias, which was also confirmed by insignificant result of Egger's regression statistical test (Egger's test P = 0.179-0.358).

CONCLUSION

Caries in the primary dentition in the GCC States was high both in terms of mean dmft (5.14) and prevalence (80.95%).

An Educational Initiative for Dubai School Nurses and Physical Education Teachers on the Management of Traumatic Dental Injuries

The aim of this study was to assess the knowledge of school nurses and physical education teachers (SN and PE teachers) about the emergency management of traumatic dental injuries (TDIs) in schools and to measure the impact of education on their knowledge. A longitudinal prospective study based on a questionnaire survey completed by 68 SN and PE teachers at three time periods (prior to, immediately after, and 3 months-post-educational intervention). Pre- and post t-test and repeated measures (analysis of variance) were used to compare the three group means for the same participants (p < .05 was considered significant). Significant improvement in the knowledge score among participants was observed between the initial survey to immediately after the educational session and to 3 months after (p = .047). Significant improvement in the choice of immediately seeking attention after tooth avulsion was observed (p = .001). The initial knowledge deficiency about the emergency management of TDIs among SN and PE teachers was improved and sustained.

Assessment of the knowledge of United Arab Emirates dentists of Child Maltreatment, protection and safeguarding

AIM

Child safeguarding is society's responsibility. Dentists are uniquely positioned to recognise Child Abuse and Neglect (CAN) in dental practice and the wider society. The United Arab Emirates (UAE) introduced a child protection law in 2016. We aimed to assess the awareness of UAE dentists of child maltreatment, protection and safeguarding. Study Design A cross-sectional survey.

MATERIALS AND METHODS

We surveyed 381 UAE dentists about the knowledge and practice of CAN and safeguarding issues using a self-administered anonymous questionnaire. Statistical analysis was carried out using Chi-square, t-test, ANOVA and Pearson's correlation test and statistical significance was set as p <0.05.

RESULTS

Over 39 % (n=152) of the responders suspected CAN; male dentists suspected more CAN than females (p=0.015). Orthodontists, paediatric dentists (p<0.001) and female dentists (p=0.001) were more knowledgeable about diagnosing CAN. Paediatric dentists attended more CAN-related postgraduate training (p<0.001) than other specialties. Over 90% (n=346) believed that CAN should be addressed, 58.1% (n=224) and 54.1% (n=206) had CAN undergraduate and postgraduate training respectively but 53.5% (n=204) were unaware of local child protection guidelines. Dentists barriers to child protection reporting were; fear of family violence (59.6%, n=227), lack of knowledge of referral process (60.2%, n=228) and lack of diagnosis certainty (54.9%, n=206). UAE dentists qualified in Western and Asian countries had fewer barriers for child protection reporting (p=0.022) than the Arab and Gulf Cooperation Council qualified dentists.

CONCLUSIONS

A large minority of UAE dentists suspected CAN. Factors influencing child protection reporting were identified. Dentists' gender, specialty, and country of qualification affected their knowledge of CAN and practice of safeguarding. Child protection training is recommended.

Oral Health Knowledge, Attitude, and Practices of Sharjah Mothers of Preschool Children, United Arab Emirates

Objective:

The improvement of children's oral health, a world global health target, is essential to general health and quality of life. Hence, the aim of this study was to assess the knowledge, attitude, and practices of mothers toward their children's oral health in Sharjah, United Arab Emirates (UAE).

Materials and Methods:

A cross-sectional interview-based study was conducted among 383 mothers of preschool children (average age 3.49 [+1.63 years]) attending Sharjah Dental Center, UAE. Statistical analysis was performed using SPSS software for Windows, version 20.0 (SPSS Inc., Chicago, IL, USA).

Results:

Adequate knowledge was found among 58.2% of mothers, 99% exhibited excellent attitude, and only 20% followed good practices toward their children's oral health. Poor knowledge and practice of mothers were significantly associated with mothers' occupation and education. Employed mothers had a significantly higher score of knowledge. Mothers with secondary education and university qualifications had significantly higher scores of practice compared with mothers with primary education.

Conclusions:

Although mothers had better than average knowledge and excellent attitude toward their children's oral health issues; most of them carried out improper practices. Mothers’ educational and employment backgrounds were significant influencing factors.

A Systematic Review and Meta-analysis of School Children's Caries Studies in Gulf Cooperation Council States

OBJECTIVES

The aim of the present study was to evaluate the prevalence and severity of dental caries school children in the Gulf Cooperation Council (GCC) area, to help the development of systematic approaches for preventive oral care programs in the GCC states and to provide sound information for oral health promotion and public health care.

MATERIALS AND METHODS

A comprehensive search to identify both published and unpublished articles concerning relevant studies of dental caries in children aged 6-16 years for their permanent teeth published from 1992 to 2016 with no language and time limit was performed. The search strategies employed electronic databases and incorporated both dental subject headings and free-text term.

RESULTS

The overall mean decayed, missing and filled teeth in the permanent teeth was 2.57, and the prevalence was 64.7% in the GCC area.

CONCLUSIONS

Most of the studies were conducted in the Kingdom of Saudi Arabia. The results may not be a true reflection, and other countries in GCC are urged to study the prevalence and severity of caries in their children population.

Prevalence of iodine deficiency disorders among school children in Saudi Arabia: results of a national iodine nutrition study

This study aimed at establishing updated data on iodine nutrition among schoolchildren in Saudi Arabia. A cross-sectional cluster survey among schoolchildren aged 8-10 years was conducted during February-April 2012. Children were clinically examined for goitre, urine and household salt samples were collected to estimate urinary iodine concenteration (UIC) and iodine content in salt. The overall goitre prevalence at the national level among 4 016 children was 4.2%. The prevalence was < 5% in all regions of the country except southern region with a prevalence of 12.7%. The median UIC of 2224 samples was 133 μg/L, with 74.3% of the surveyed children with UIC ≥ 100 μg/L. Analysis of salt samples (n = 4242) revealed that 69.8% of households were consuming adequately iodized salt. The findings suggest iodine sufficiency at the national level, however southern region still has a goitre prevalence of mild degree severity and the proportion of households consuming adequately iodized salt is still below recommendations.

In vivo exposure therapy for the treatment of an adult needle phobic

Dental anxiety is a widespread problem. Behavioural interventions are effective in reducing dental anxiety and dentists are well placed to carry out these interventions. This article aims to familiarize dentists with simple behavioural techniques that can be used to treat patients presenting with dental anxiety. A case study detailing the assessment and treatment of an uncomplicated needle phobia using in vivo graded exposure is included in order to demonstrate the use of these techniques.

CLINICAL RELEVANCE

Familiarity with simple, behavioural interventions for dental anxiety will enable dentists to respond appropriately to patients who present with mild fear and anxiety. Early intervention may play a role in the reduction of phobic anxiety in the dental setting. Dentists with an interest in behavioural management may also wish to treat patients with uncomplicated dental phobia.

Adalimumab for the Treatment of Refractory Sciatica Induced by Disc Prolapse

Ten patients with back pain and sciatica were selected according to certain inclusion criteria for a study to assess the efficacy of the Anti TNF agent Adalimumab in the treatment of refractory sciatica pain induced by a lumbar disc prolapse in patients who failed to improve following lumbar epidural steroid or disc surgery. Each was given a subcutaneous injection of 40mg Adalimumab repeated after two weeks. Patients were assessed regularly on weeks 0, 2, 4 and 8 employing the Visual Analogue Score (VAS) for leg pain and back pain and the Straight Leg Raising (SLR) test. The median improvement of the leg pain VAS was 55. Median improvements of back pain VAS was 37. Median improvement of the SLR was 45. The study demonstrated the beneficial effect of adalimumab therapy in reducing the back and leg pain associated with sciatica in this difficult to treat group of patients. The improvement of leg pain was more significant than that of back pain. The response was better in patients with symptoms of shorter duration and with less SLR restriction at base line.

Age-specific reference ranges for prostate specific antigen-total and free in patients with prostatitis symptoms and patients at risk

BACKGROUND

Prostate-specific antigen (PSA) is a tumor marker helpful in the diagnosis and follow-up of prostate cancer. However, PSA level may rise due to other causes than prostate cancer such as benign prostatic hyperplasia (BPH), acute prostatitis, chronic bacteria and a bacterial prostatitis. Total serum PSA (TPSA) and free prostate-specific antigen (FPSA) levels of patients with prostatitis symptoms as well as these levels in male population at risk but without clinical prostatic diseases (>40-years-old) with regard to age should be documented in order to increase the sensitivity and specificity of PSA in prostate carcinoma.

METHODS

A comprehensive urological examination was performed on 1150 male patients over the age of 40 with prostatism symptoms from the random-sample community based in with no diagnostic prostate cancer. Men with PSA level 4.1 ng/ml or greater were referred for biopsy and those with positive biopsies or with medical record, cancer registry, or self-reported evidence of prostate cancer were excluded. Data were studied as a function of age to determine the usefulness of measuring TPSA and FPSA as screening tests for risk patient's cancer.

RESULTS

Because of the greater variability at older ages, the 95th percentile increased faster than the median, the following age-specific reference ranges of TPSA and FPSA for patients with prostatism symptoms were as follows: 3.1 and 0.7 ng/ml for the age group 40-49 years, 4.4 and 0.89 ng/ml for the age group 50-59 years, 5.6 and 1.3 ng/ml for the age group 60-69 years, and 6.3 and 1.8 ng/ml for age group 70-79 years. There was a continuous increase in TPSA and FPSA means and medians with significant correlation (P<0.001, P<0.005) and advancing age group. The aim of this study was to find out age-specific values and ranges of TPSA and FPSA in patients with prostatism symptoms to ensure low false-positive biopsy rates.

Response of four indigenous cattle breeds to natural tsetse and trypanosomosis challenge in the Ghibe valley of Ethiopia

A comparative study on the response of four indigenous cattle breeds of Ethiopia, namely Abigar, Horro, Sheko and Gurage, to natural challenge of trypanosomosis in the Tolley-Gullele area of the Ghibe valley has been undertaken from August 2000 until August 2004. Fifty female yearlings each of Horro, Sheko and Abigar and 31 of the Gurage were purchased from their natural habitats and introduced in to medium to high tsetse-trypanosomosis challenge area of the Ghibe valley. While the natural habitats of first three breeds are naturally infested with tsetse flies and trypanosomosis, that of the Gurage is known to be very minimal, if any, and hence the Gurage breed was used in this study as the known susceptible breed. During the study animal health, production performance and tsetse fly situation were monitored monthly. The Sheko breed has manifested very significantly (p<0.001) high overall average packed cell volume (PCV) values (25%) compared to that of Abigar (24%), Horro (23%) and Gurage (22%). It also had the lowest mean trypanosome prevalence rate of 9% against 23% of Horro, 26% of Abigar and 27% of Gurage, and the least number of Berenil treatments (1.36) compared to Abigar (4.0), Horro (4.6) and Gurage (6.7). While the Abigar manifested high sensitivity and frequent death to PCV depression, the Horro showed strong resilience to PCV depression and better response to Berenil treatment assistance. At this stage the Sheko breed was also found to be equal to the other breeds in its reproductive performance. These results need to be substantiated with further in-depth investigation including immune response, animal behavior and environmental influences.

Deaths in children during an outbreak of hand, foot and mouth disease in Peninsular Malaysia--clinical and pathological characteristics

From July through December 1997, 11 previously healthy children in Peninsular Malaysia succumbed to an illness clinically characterised by an acute severe refractory left-ventricular failure, following a brief prodromal illness, in the midst of an outbreak of hand, foot and mouth disease (HFMD), similar to the reported experience in Sarawak and Taiwan. Retrospective reviews of the clinical features and results of laboratory, pathological and virological investigations of cases were conducted. The median age of the 11 case-patients was 31 months (range, 13 to 49 months); 6 were males. A brief prodromal illness of 3 days (range, 2 to 5 days) was characterised by fever (axillary temperature > 38 degrees C) (100%), oral ulcers (72%), extremity rashes (45%) and significant vomiting (55%). Upon hospitalisation, 7 of 11 case-patients had features suggestive of cardiogenic shock, while 4 of 11 case-patients developed shock during hospitalisation as evidenced by marked sustained tachycardia (heart rate > or = 180 beats per minute), poor peripheral pulses and peripheral perfusion, mottled extremities, pulmonary oedema (haemorrhagic pulmonary secretions in 8 of 11 cases during tracheal intubation, often precipitated by conservative crystalloid boluses, and radiographic evidence of acute pulmonary oedema in 5 of 7 cases) and markedly impaired left ventricular function on echocardiographic examination (7 of 7 cases). Three of 4 case-patients had aseptic meningitis while one case-patient also had an acute flaccid paraparesis. Despite supportive therapy, death occurred within a median of 13.4 hours following hospitalization. Post-mortem findings (all 8 specimens examined) consistently demonstrated brain-stem encephalitis with foci of neuronal necrosis and micro-abscesses. None of the 11 specimens examined revealed histological evidence of myocarditis. Enterovirus 71 (EV71) was detected in 10 of 11 case-patients, many (7) from various sterile tissue sites (5 from central nervous tissues). No other viruses were isolated or identified. Clinical features and pathological studies closely paralleled the reported experience in Sarawak and Taiwan. The uniform necropsy findings of necrotizing brain-stem encephalitis coupled with essentially normal myocardial histology, in concert with the concurrent and consistent detection of EV71 points to a primary EV71 encephalitis; as yet unclear neurogenic mechanisms may account for the cardiovascular manifestations.

Cellular mechanisms of osteoclast formation and lacunar resorption in giant cell granuloma of the jaw

BACKGROUND

Giant cell granuloma (GCG) is an osteolytic tumour of the jaw which is characterised by the presence of both mononuclear and multinucleated (osteoclast-like) giant cell components. The nature of these component cells and the pathogenesis of the extensive osteolysis associated with this lesion is uncertain.

METHODS

Using cell culture techniques and immunohistochemistry, we defined the phenotypic characteristics of the mononuclear and multinucleated cells present in four cases of GCG of the jaw. We also analysed the cellular and humoral factors associated with osteoclast formation and osteolysis in these tumours and determined whether GCG stromal cells are capable of supporting osteoclast formation.

RESULTS

GCG-derived giant cells expressed the phenotypic characteristics of osteoclasts (TRAP+, VNR+, and calcitonin responsive) and were capable of lacunar resorption. In addition to macrophages, the mononuclear cell population contained numerous spindle-shaped stromal cells which proliferated in culture and expressed RANKL; these GCG-stromal cells were capable of supporting human osteoclast formation from circulating monocyte precursors.

CONCLUSION

Our findings indicate that the giant cells in GCG of the jaw are osteoclast-like and formed from monocyte/macrophage precursors which differentiate into osteoclasts under the influence of RANKL-expressing mononuclear stromal cells found in this lesion.

The distribution of ixodid ticks (Acari: Ixodidae) in central Ethiopia

Ixodid ticks were collected from domestic animals, mainly cattle, in 11 administrative zones covering 84 districts in central Ethiopia over a period of 2 years (July 1996 to June 1998). Nineteen tick species were identified. Four of these belonged to the genus Amblyomma, one to Boophilus, two to Haemaphysalis, three to Hyalomma and nine to Rhipicephalus. Amblyomma variegatum and Rhipicephalus evertsi evertsi were present in all 11 administrative zones and, with the exception of Afar, Boophilus decoloratus was present in nearly every district in which collections were made. These three species constituted more than 50% of all ticks collected. Amblyomma cohaerens and Rhipicephalus bergeoni were common in the west of the survey region and Rhipicephalus pulchellus in the east. Except for B. decoloratus, of which more females than males were collected, the numbers of male ticks recovered were equal to or exceeded those of females. Mortality in crossbred dairy cattle caused by heartwater (Cowdria ruminantium infection) was reported during the survey period. An integrated approach to tick control is suggested.