THE COVID-19 PANDEMIC LOCKDOWN'S IMPACT ON ROUTINE CHILDHOOD VACCINATION.

The COVID-19 pandemic limits worldwide healthcare access, particularly mandated childhood vaccines. The frequency and mean of purposefully delayed immunizations in infants aged ≤1 year throughout the COVID-19 pandemic in Nineveh, Iraq, were studied. A retrospective observational study of vaccination data in Nineveh, Iraq, was conducted throughout the pre-pandemic period in 2019, the pandemic period in 2020, and comparable months in 2021-2022. The study covered every vaccination administered at ages neonate, 2, 4, 6, 9, and 12 months. The total number of visits mean for the period (Mar-May) 2020 (comprehensive lockdown period) decreased (-18.5%) against (March-May) 2019, and around 2726 children per day were missing immunization. All scheduled vaccines for children aged ≤12 months showed a decrease. The lowest monthly vaccination coverage rate was in March 2020 (61.0%), with the vaccine coverage rate of IPV (70.25%) being the lowest one, then the BCG vaccine at 70.39%, the Pentavalent vaccine at 70.98%, the HBV vaccine at 74.33%, OPV vaccine 79.3%, Measles vaccine (79.45%), and for MMR vaccine 87.34%. The COVID-19 pandemic's significant effects on childhood immunization, recovered in the months that followed but did not reach that before the pandemic in 2019. Intentional vaccination disruption exposes young infants to avoidable infectious illnesses, emphasizing the importance of personalized interventions to improve immunization visits as well as secure the delivery of services.

One-year Adhesive Bond Durability to Coronal and Radicular Dentin Under Intrapulpal Pressure Simulation.

OBJECTIVE: To evaluate the microtensile bond strength (µTBS) of different adhesives to coronal vs radicular dentin after one year of storage in artificial saliva and under intrapulpal pressure (IPP) simulation. METHODS AND MATERIALS: Roots of 36 freshly extracted premolars were sectioned 5 mm apical to the cemento-enamel junction and pulp tissue was removed. Buccal enamel and cementum were trimmed to obtain standardized flat dentin surfaces. Specimens were divided into three groups (n=12/group) according to the adhesive strategies utilized: a two-step etch-and-rinse adhesive; a two-step self-etch adhesive; and a single-step self-etch adhesive. Adhesives and resin composite were applied to coronal and radicular dentin while the specimens were subjected to IPP simulation. After curing, specimens were stored in artificial saliva at 37°C in a specially constructed incubator while the IPP was maintained for either 24 hours or one year prior to testing. Bonded specimens were sectioned into sticks with a cross section of 0.8 ± 0.01 mm(2) and subjected to µTBS testing. Data were statistically analyzed using multi-way analysis of variance (ANOVA) with repeated measures; one-way ANOVA tests; and Bonferroni post hoc test (p<0.05). Failure modes were determined using a scanning electron microscope at 100× magnification. RESULTS: ANOVA results revealed a statistically significant effect for the adhesive strategy (p<0.001) and storage period (p<0.001) as well as for their interaction (p=0.024) on the µTBS. However, dentin substrate and its interactions revealed no significant effects. For both dentin substrates, the two-step self-etch adhesive revealed statistically significantly higher µTBS values than did the other two adhesives after 24 hours and one year of storage. After one-year storage, a significant decrease in bond strength values of all tested adhesives occurred with both dentin substrates. Modes of failure were mainly adhesive and mixed. CONCLUSIONS: Adhesives were not sensitive to structural differences between coronal and radicular dentin even after one year of storage under IPP simulation. However, all tested adhesive systems strategies were sensitive to storage.

Bond durability of self-etch adhesive to ethanol-based chlorhexidine pretreated dentin after storage in artificial saliva and under intrapulpal pressure simulation.

OBJECTIVE: To evaluate the bond strength durability of a single-step self-etch adhesive to dentin pretreated with either ethanol-based chlorhexidine (ECHX) or water-based chlorhexidine (WCHX) after storage in artificial saliva and under intrapulpal pressure simulation (IPPS). METHODS: The occlusal enamel of 30 freshly extracted premolars was trimmed to expose midcoronal dentin. Roots were sectioned to expose the pulp chamber. Specimens were distributed over three groups (n=10) according to the dentin pretreatment used. In the first group, Adper Easy One (3M ESPE) was applied to the dentin surfaces according to the manufacturer's instructions (control group). In the second group, dentin was pretreated before bonding with 1 mL of 2% CHX diacetate dissolved in 100% ethanol (ECHX). The third group received the same pretreatment; however, CHX was dissolved in distilled water (WCHX). Pretreatment and bonding were carried out while the specimens were subjected to IPPS. Resin composite (Valux Plus, 3MESPE) buildups were made. After curing, specimens were stored in artificial saliva and under IPPS at 37°C in a specially constructed incubator (n=5/group) either for 24 hours or six months prior to testing. Thereafter, bonded specimens were sectioned into sticks with a cross section of 0.9 ± 0.01 mm(2) and subjected to microtensile bond strength (µTBS) testing (n=25/subgroup) using a universal testing machine. Data were statistically analyzed using two-way analysis of variance (ANOVA) with repeated measures, one-way ANOVA , and Bonferroni post hoc tests (p≤0.05). Failure modes were determined using a scanning electron microscope. RESULTS: After 24 hours of storage, control and WCHX groups revealed significantly higher µTBS than the ECHX group. After six-month storage in artificial saliva and IPPS, only the WCHX group maintained its µTBS value. The predominant mode of failure was the mixed type, except for the ECHX group, which was mostly adhesive. CONCLUSION: Pretreatment of the dentin with ECHX had a negative effect on bonding of the tested single-step self-etch adhesive; however, WCHX showed bond stability under IPPS.

High-frequency (10-18 kHz) hearing thresholds: reliability, and effects of age and occupational noise exposure.

The objective was to investigate the reliability and effects of age and noise on high-frequency hearing thresholds. A cross-sectional study was used involving 187 exposed and 52 non-industrial noise-exposed subjects selected randomly from noise-exposed and non-industrial noise-exposed subjects, respectively. Each subject was tested with both conventional-frequency (0.25-8 kHz) and high-frequency (10-18 kHz) audiometry. Test-retest results showed that high-frequency audiometry (HFA) was as reliable as the conventional procedure. Although the inter-subject variation was large, the intra-subject variation was small, indicating that HFA can be used more reliably than the conventional procedure to monitor individual cases over time. Both the hearing threshold at high frequencies and the upper frequency limit deteriorated as a function of age and frequency. The exposed subjects had significantly higher hearing thresholds than the non-exposed subjects at all the high frequencies tested, the difference between the two groups being greatest at 14 kHz. Multivariate analysis indicated that age was the primary predictor and noise exposure the secondary predictor of hearing thresholds in a high frequency range (10-18 kHz). In contrast, multivariate analysis indicated the reverse order-noise exposure as the primary predictor, then age-for a conventional frequency range (0.25-8 kHz). The results of this study suggest that HFA might be used as an early indicator for noise-induced hearing loss and acoustic trauma rather than audiometry at a conventional frequency (4 kHz), particularly for younger groups.

Occupational noise exposure and hearing loss of workers in two plants in eastern Saudi Arabia.

OBJECTIVE: To determine the prevalence of hearing loss associated with occupational noise exposure and other risk factors. DESIGN: A cross-sectional study involving 269 exposed and 99 non-exposed subjects (non-industrial noise exposed subjects) randomly selected. Current noise exposure was estimated using both sound level meter and noise-dosimeter. Past noise exposure was estimated by interview questionnaire. Otoscopic examination and conventional frequency (0.25-8 kHz) audiometry were used to assess the hearing loss in each subject. RESULTS: 75% (202 subjects) from the exposed group were exposed to a daily Leq above the permissible level of 85 dB(A) and most (61%) of these did not and had never used any form of hearing protection. Hearing loss was found to be bilateral and symmetrical in both groups. Bivariate analysis showed a significant hearing loss in the exposed vs non-exposed subjects with a characteristic dip at 4 kHz. Thirty eight percent of exposed subjects had hearing impairment, which was an 8-fold higher rate than that found for non-exposed subjects. Multivariate analysis indicated exposure to noise was the primary, and age the secondary predictor of hearing loss. Odds of hearing impairment were lower for a small sub-group of exposed workers using hearing protection (N=19) in which logistic regression analysis showed the probability of workers adopting hearing protective devices increased with noise exposure, education, and awareness of noise control. Hearing loss was also greater amongst those who used headphones to listen to recorded cassettes. CONCLUSION: Gross occupational exposure to noise has been demonstrated to cause hearing loss and the authors believe that occupational hearing loss in Saudi Arabia is a widespread problem. Strategies of noise assessment and control are introduced which may help improve the work environment.

Possible effects of iodized salts on the taste, colour and consistency of traditional pickles

A national survey was conducted in Jordan in 1991 to determine the prevalence of iodine deficiency disorders. A sample of 2679 children aged 8-10 years was screened and the results revealed that 37.7% of the study sample were suffering from iodine deficiency disorders. Iodization of salt is the preferred approach for supplementation. The present study was conducted to identify the effect of iodized salt on the colour, taste and consistency of traditionally prepared pickles. It was concluded that iodized salt has no effect on any of the sensory characteristics of traditionally prepared pickles

Hearing screening of infants at King Fahd Hospital of the University.

The detection of hearing impairment in neonatal life and prompt intervention prevents the hazards of physical and developmental delay in speech. During a 12-month period between April 1987 and March 1988, the hearing of 151 well babies and 30 high-risk babied aged 6 to 12 months attending the pediatric clinics of King Fahd Hospital of the University (KFHU), Al-Khobar, were screened. The modified Ewing-Stykar test was performed on all babies. Tympanometry, stapedial reflex, and brainstem evoked response (BERA) were carried out in the well babies who failed the screening test and in all high-risk babies. The failure rate was found to be 4.6% and 43.3% and the validity index 71.4% and 92.3% for the well and high-risk babies, respectively. The results of this limited study encourages us to recommend the implementation of this screening test in all the well baby and the high-risk baby clinics in the Kingdom of Saudi Arabia.