The study is a non-randomized controlled trial which was conducted over duration of six months in KLE Institute of Dental Sciences, Bengaluru, Karnataka, India. The sample size was determined using G*Power software version 3.1.9.2. Alpha error was set at 0.05, effect size (Cohen’s d) as 0.5 and Power at 90%, the sample size was estimated to be 36, this was rounded off to 40. Visually impaired children from Snehadeep school for blind, Bengaluru, belonging to the age group 8-18 years, who were mentally sound to answer questionnaire and who can see less at 20 feet than that a person with normal vision can see at 200 feet (a visual acuity is 20/200) were included in the study [11]. The children were selected using simple random sampling technique. Children affected with mental retardation, mentally handicapped, orthopaedic defects, cerebral palsy and children without consent were excluded from the study. The Ethical consent was obtained from the Ethical review Board of the Institute, which was in accordance with the principles of the Declaration of Helsinki (1975, rev. 2000). Informed consent was obtained from the participating subjects.

The children selected were subjected to Type 3 intraoral examination [12]. Dental plaque status was assessed by plaque index – Silness and Loe (1964) [10]. The questionnaire included questions of knowledge regarding dentition and oral health care, dental health behaviour (brushing frequency and other oral aids), attitude towards oral health (maintenance of teeth and importance of dentist) and knowledge regarding diet [13-15]. This was converted and delivered in Braille format which was done by Snehadeep school for blind and was validated in a pilot study with Cronbach’s alpha 0.72 at the beginning of the study. The oral health status was assessed using the plaque scores which was collected on the same day.

Oral health education module was constructed which involved 3 methods:

Questionnaire was administered before the start of the study, to check for the KAP among the participants. The interventions were conducted by the primary investigator and the plaque scores were recorded by secondary investigator. The intervention was given on the first Saturday of every month for six months, the oral health education module intervention lasted for around 30 minutes. The same questionnaire was distributed after six months to assess the changes in KAP regarding oral health status and plaque scores were determined.

The collected data on oral health awareness questionnaire and plaque status and associated variables were analysed using Chi-square-test and Wilcoxan signed test with SPSS software version 22.0.

A non-randomized control trial was conducted among 40 visually impaired individuals attending special school for blind.

Males formed almost two third’s of the population, and the age group of 15-18 years formed nearly half of the population [Table/Fig-1]. The overall KAP was lower in the preintervention period among the visually impaired children with mean score of 6.98 after the modified oral health education session, the KAP was increased to a mean score of 14.68 with minimum score of 8 and maximum score of 16 which was statistically significant at p<0.001 [Table/Fig-2]. The KAP scores were also converted to percentages and divided into grades such as below average (< 30%), average (31%-70%) and above average (71%-100%). The number of students had increased in the above average KAP group in the after session with 95% increase while in the below average group the number of students has decreased with 4% in the after session [Table/Fig-3].

[Table/Fig-1]:

Descriptive data of total sample and age distribution of the study population.

The oral hygiene of the children was assessed using plaque index before and after the intervention. The scores were categorized into good, fair and poor. Improvement was seen in the visually impaired children before and after receiving oral health education as only 5% of the children could be categorized as having good plaque scores before the intervention and this number increased to 67% after the intervention. This difference was found to be statistically significant at p<0.05 [Table/Fig-4]. Behaviour change was one of the main objectives of conducting this study, changes in daily brushing frequency was also analysed and it was found only 37.5% of the students brushed twice in the preintervention period and this increased to 92.5% after the oral health education session was held. The knowledge regarding anatomy of tooth, flossing of teeth and dietary habits also increased postintervention. These differences was also found to be statistically significant at p<0.05 [Table/Fig-5]. Thus, the study opines that oral health education of blind children using innovative methods is effective in improving their KAP towards oral health and can also lead to behaviour modification.

Subjects with disabilities are prone to have higher incidence of dental caries and more problems in accessing dental care. Majority of them do not know the basic preventive aspects regarding oral health. Preventive and oral health education approaches are more effective than the standard dental care when it comes to visually impaired children. A special protocol and design is essential to inculcate a good oral hygiene practice in them.

Chang S and Shih Y observed that students who were visually impaired were less aware of their dental health [17]. Poor knowledge regarding dental health was seen in the present study as well, indicating that their elementary knowledge about the oral cavity was poor. It was found that at the cognitive level also, there was a lack in knowledge. A person suffering from visual disability, despite being in the society, cannot receive the visual social stimuli; so, most of the children were less perturbed about their oral health. In the present study, most of the visually impaired children were unaware of the term “Floss”. This can be explained by their poor oral health knowledge as well as their institutional background where using of floss was never taught. This finding was in accordance to study done by Chang S and Shih Y, where 40% of the sighted participants used both tooth brush as well as floss for teeth cleaning, but only 20% of the participants with visual impairments did so [17]. So, it is necessary to teach appropriate tooth flossing technique with the help of repeated motivation. Also, after the oral health education session, most of them showed a change in their behaviour. The number of children brushing twice a day increased after the intervention. This was in accordance with a study conducted by Ahmad MS et al., [14] It was seen that in this short period, the students developed the habit of brushing their teeth with Modified Bass technique with stipulated amount of toothpaste. It was in accordance to the study conducted by Nandini N, where the cognitive level of dental health knowledge as well as oral health practices was significantly increased with one to one health education to the visually impaired children [18].

It was seen in the study that knowledge about consuming sugary foods and beverages was also poor among the visually impaired children. This was in agreement with the study conducted by Vigild M et al., who reported a high consumption of sugar containing products among the blind children [19]. In our study, the postintervention period showed a significant increase in the knowledge about sugar consumption with 97.5% of the children understanding the fact that sweets that are sticky and which dissolves slowly are the major etiological factors for dental caries causation and that the amount of sugar intake is not so important as compared to the frequency of sugar consumption. The removal of plaque and debris from the teeth is an ability that can be mastered only when individuals have the skill to manipulate the toothbrush and understand the objectives of these activities [20]. In the present study, there was fair plaque scores (80%) among the visually impaired individuals in the preintervention period which was in accordance to study done by Sujal P [21]. The probable reasons for poor oral hygiene in these visually impaired individuals could be due to low power of concentration or lack of motor skills or problem in communication/understanding of instructions and poor co-operation leading to difficulty in learning and adaptation of the oral hygiene practices. But after the stepwise implementation of the health education module, the fair oral plaque scores reduced to 30% among the visually impaired children showing the effectiveness of the motivation element within the programme.

This oral health education module for individuals who are blind can act as a template in planning and improving the oral hygiene of these individuals so that the disabled individuals will not feel left out in this fast moving world in terms of health.

The limitations of the study was that the number of individuals selected for the study were from the same institute and the total number of participants was small.

To improve the oral hygiene status of individuals with disabilities is a daunting task, but it can be achieved if even the parents or guardians are given suitable health education. So, the differing needs of these special children and their caregivers needs to be addressed in future. This study only provides an insight into the increase in awareness and increase in oral health maintenance after a comprehensive oral health programme in a relatively small sample. So, a mass study is required if any other factors are required to be modified for the improvement of oral health education among visually impaired children.

This modified dental health education module with its three pillars based on a specially designed educative module comprising of tactile dental models, a specially designed music based brushing technique and health education booklet in Braille will definitely improve knowledge and attitude towards oral health among these visually impaired children.