The Effect of Visual Pedagogy and Probiotics in Improving Oral Hygiene of Hearing Impaired Children in the Age Group 6-14 Years

Introduction

Hearing is the modality of sensory origin by which children develop speech. Children with severe bilateral hearing loss (70– 89 dB loss) or profound hearing loss (> 90 dB loss) fall into the category deaf.¹

In 2003, population-based surveys in India using the WHO protocol estimated the prevalence of hearing impaired individuals to be 6.3% or approximately 63 million people suffering from significant auditory loss.

The adult onset deafness in India had an estimated prevalence of 7.6% while the childhood onset deafness was 2%.²

Children with hearing impairment require frequent assessment of oral hygiene. Hence, in India, studies³ were carried out which observed a higher prevalence of gingivitis and caries among the hearing impaired children when compared with normal children. This displays the immense need for inclusive health-care provisions to beimplemented for every hearing impaired child.

Visual learning strategies play a very important role in the literacy skill enhancement of hearing impaired children. This can also be employed to inculcate oral hygiene measures in these children. In the recent decade, we have seen a trend in growing significance of specific treatment over non-specific treatment options.⁴ Probiotics help in attaining specific treatment against plaque microbiology by modifying it to commensal from pathological.

This purpose of this study was to assess the effect of visual pedagogy, probiotic based mouth rinse and a combination of both on oral hygiene of the hearing impaired children.

Materials and Methodology

A prospective interventional study was planned. Fortyfive institutionalized children with hearing impairment aged 6–14 years from government and private special schools in Bengaluru, Karnataka were selected for the study using random sampling technique.

Prior to the initiation of study, ethical clearance and informed consent were taken from the administrative bodies and the guardians of all children respectively. Children who did not show history of antimicrobial consumption for past one month were considered for the study. Any child suffering from mental or systemic illness, or any other special health care needs was not included in the study.

The oral cavity of selected children was examined under natural light. Oral hygiene of these children was assessed using Green and Vermillion OHI-S index (1964) with mouth mirror and explorer.⁵ (Figure 1)

pH-measuring strips (Jal Tara pH testing paper) were used to assess salivary pH, by placing the strip on the dorsal surface of the child’s tongue for a time period of 30s. Manufacturer’s recommended standardized color coded chart was used to note the colour change of pH strip (Figure 2, Figure 3). The assessment was done at the baseline by one examiner to eliminate bias.

Division of children randomly into three groups was done:

Group 1- Visual pedagogy to deliver oral hygiene instructions (Figure 4) – the video consisted of two parts. Part one where instructions were given using a sign language and part two where tooth brushing was demonstrated on a 3D model of human dentition using Fone’s technique.

Group 2- Probiotic mouth rinse was used (Figure 5) - Individual sachets of Darolac probiotic (Aristo pharmaceuticals, India) (Figure 6) was used. Lactobacillus rhamnosus (LGG), Bifidobacterium longum, and Saccharomyces cerevisiae combination is provided in one sachet of one-gram powder (1.25 billion freeze‑dried combination of bacteriae). After training the children for rinsing using 20 ml filtered water, the mouth rinse containing probiotic was freshly prepared by dispensing the contents into 20 ml of filtered water and the children were taught to rinse 5 ml of solution for one minute and swallow it. This was repeated until the preparation (i.e., 20 ml content) was consumed completely.⁴ This exercise was carried out in the institution 30 minutes after lunch for six weeks under the guidance of trained teachers.

Group 3- Combination of both (in the same pattern as group two) was used in children of this group. The salivary pH and oral hygiene status were re-evaluated after six weeks (Figure 7) once oral hygiene training was carried out for all the groups.

Statistical Analysis

Descriptive and inferential statistical analysis was done. Kruskal-Wallis test and Mann-Whitney U test were used to find the significant difference between the three groups. Wilcoxon test was used to check the difference within the group over a timespan. Significance was assessed at 5% level of significance.

Results

1. Comparison within group for difference in OHI-S and pH at time intervals

Inference: There was significant reduction of OHI scores in all the three groups, while pH increased significantly in group 2 & 3.

2. Overall intergroup comparison

Inference: Statistically significant difference was noted between the groups for difference in OHI & pH.

3. Comparison between the two groups for OHI difference & pH difference

Inference: Significant difference between the groups 1 & 3, 2 & 3 for difference in OHI was seen statistically and significant difference between the groups 1 & 2, 1 & 3 for difference in pH was noted.

The optimal pH maintenance and overall reduction in OHI-S scores was noted in Group 3 which used combination of both.

Discussion

Hearing is a prime sensory function that helps in child’s cognition: approaching footsteps, the pitter-patter of rain, car horns, and dog barks. Hearing is the sensory modality through which children perceive speech. Noises above 90 dB are perceived as loud by normal human ear. Individuals with a bilateral hearing loss of 70–89 dB (severe) or >90 dB (profound) are termed as deaf.² As the children are not able to have conversational speech, which is about 60 dB, they eventually find it difficult to talk normally. Indeed, difficulty in talking at the right age helps in early diagnosis of hearing impairment.

According to the estimates of the WHO in 2005, people suffering from hearing impairment, i.e. moderate-toprofound hearing loss in both ears (hearing loss >41 dB) are estimated to be 275 million. It is in fact considered the second most common reason for years lived with disability (YLD) which is 4.7% of the total.⁶ In the South-east Asian region, hearing impairment is high with prevalence of 4.6% to 8.8%. In 2003, surveys on population with hearing impairment were done in India using WHO protocols, and the prevalence was found to be 6.3% or approximately 63 million people affected by significant auditory loss. In India, adult onset deafness was found to have 7.6% prevalence and prevalence of childhood onset of deafness being 2%.⁶

The prime sequel of childhood hearing impairment is that it hinders the learning of speech — both speaking as well as comprehending, because of which, the oral health needs of these children remain largely unmet. Studies⁷ on assessment of oral hygiene status of children were conducted reporting a higher prevalence of gingivitis and caries in children with hearing impairment in India in comparison with normal children. Thus there is an absolute necessity for planning and implementing health-care facilities for children regardless of their health condition.⁷ Therefore, an innovative and comprehensive method to provide oral health should be introduced by pediatric dentists.

Preventive strategies like tooth brushing habits twice a day and flossing often should be inculcated to maintain good oral health in these children. One of the possible difficulties faced when these children are approached is the difficulty to train them. Visual learning methods can be employed to allow these children gain adequate literacy skills. Hearing impaired individuals are greatly dependent on visual mode of communication and learning. Studies have stated that visual aids can be effective than other aids in such situations.⁸ Hence, oral hygiene instructions and practices can be provided and reinforced by visual learning strategies.

In addition, the treatment protocols today have changed from being non-specific to becoming more specific. These comprise the usage of probiotics to modify pathological organisms to commensal. In 2002, WHO stated probiotics as “live microorganisms which when administered in adequate amount confer a health benefit on the host.^”9,10 They were stated as “correctives of the ecosystem” as they stabilize oral ecosystem by establishing a balance. These newer avenues can be used to help children with special health care needs improve oral hygiene.

Montalto and collegues, in 2004 stated that the administration of probiotics orally, both in capsules and in liquid form, significantly increased salivary counts of lactobacilli while streptococcus mutans levels were not modified significantly.¹¹ While Meurman et al., in their study suggested that L. rhamnosus GG (LGG) can inhibit colonization of streptococci and reduce the caries incidence in children.¹²

From a periodontal view, a study by Grudianov et al in 2002 examined probiotic tablets in complex treatment of gingivitis and different degrees of periodontitis.¹³ Drug Tantum Verde was used for the treatment of the patients in control group. In cases of periodontitis and gingivitis, probiotics showed better normalisation of flora in comparison with Tantum Verde.

Nase and collegues¹⁴ in 2001 did a comparative study on LGG containing milk and normal milk and its effect on caries. It was concluded that LGG might have beneficial effects on oral health of children as they showed reduced caries.

Peneva and Doichinova ¹⁵ also employed the visual pedagogy method to motivate and improve oral hygiene in deaf kids over a time period of one year. Even though it was time consuming and required successive reinforcements, the author concluded that once practiced, it can bring out tremendous improvement in oral hygiene.

Neeraj et al¹⁶ suggested the use of probiotic mouthwash swished for 60s before swallowing, during fixed orthodontic treatment for use as an adjunctive measure along with regular brushing for improvement of periodontal status.

In the present study, visual pedagogy to teach oral hygiene in hearing impaired children and usage of mouthwash with probiotic microbes demonstrated significant results in reduction of plaque accumulation and improvement in OHI-S scores (Table 1). Further assessment in pH of saliva showed that at the start of the study, pH was found to be below critical pH level. After using the mouthwash with probiotics, it showed rise in value above critical pH (Tables 1 and 2). Neutral salivary pH depicts a good oral hygiene, healthy periodontal tissue and less chance of cariogenicity, thus stating that the use of mouth rinse containing probiotics had a non-specific ecological impact on oral cavity.¹⁰ The combined effect of mouth rinse containing probiotic microbes and visual pedagogy resulted in reduction of plaque accumulation in the study groups.

Conclusion

The burden of dental diseases has always been indirectly proportional to the performing oral hygiene practices. Children with disabilities tend to be more vulnerable to oral health related diseases. As oral health professionals, it is our foremost responsibility to teach these children accurate maintenance of oral hygiene. Implementing newer teaching modalities like visual pedagogy and combining them with potent preventive techniques like probiotics will go a long way in sustaining optimal oral hygiene. Acknowledgement The authors would like to thank Dr Anisha Jenny and Dr Richa Lakhotia for their support.

Conflicts of Interest of each author/ contributor: nil

Conflict of Interest

None.