Knowledge and Oral Health Related Behaviour Among Visually Impared Subjects in Addis Ababa, Ethiopia

Background: Oral health is a global issue. It has an enormous impact on the overall health and well-being of an individual. In addition, many studies indicate visual impairment as one of the constraints for proper maintenance of oral hygiene. However, little is known about visually impaired individuals' oral health knowledge and behavior in Ethiopia, Specically in Addis Ababa. Therefore, this study is conducted to assess the oral health knowledge and related behaviors among participants with visual impairment in Addis Ababa, Ethiopia. Methods: The study was carried out at the Ethiopian National Association for the blind, located in Addis Ababa, the capital city of Ethiopia. Convenience sampling was used from the visually impaired library attendees' in the blind association. Sixty-ve individuals, of which 46 males and 19 females, agreed to take part in the study. Of these, 30.8% had partial and 69.2% total visual impairment. Results: 61.3% with totally and 72% with partially visually impaired scored high in the knowledge of caries causes respectively. The use of tooth brushing was conrmed by 42.2% with totally and 25% with partially visually impaired. The use of Traditional chewing sticks was conrmed by 57.7% with totally and 30% with partially visually impaired individuals. Moreover, both (Toothbrush & Traditional chewing stick) was used by 35.5% totally and 55% partially visually impaired individuals, respectively. Conclusions: The study showed the awareness about the causes of Dental Caries among the visually impaired was high. However, the majority of them had a signicant misconception about the causes of dental caries.

concern about how people practice oral health or their behaviors and maintains their oral health.
The WHO has estimated that globally about 285 million people are visually impaired, and among these blind people are 39 million and 246 million with low vision [7]. While Bourne wrote 253 million people live with Vision Impairment: 36 million are blind, and 219 million have moderate to severe impairment [8]. Even though over 80% of global visual impairment is preventable or treatable, millions remain at risk of visual loss due to the lack of eye-care services [7].
Blindness is de ned by WHO as having a Visual acuity of less than 3/60 m or corresponding visual eld loss in the better eye with the best possible correction; meaning that whilst a blind person could see 3m, a non-visually impaired person could see 60m. Visual impairment relates to a person's eyesight which cannot be corrected to normal vision [9].
According to the American Foundation for the Blind, the clini cal parameters to de ne blindness from a legal perspective (legally blind) correspond to a central visual acuity of 20/200 or less in the better eye and/or a visual eld of 20 degrees or less. Individuals diagnosed with legal blindness usually still possess some vision. Total blindness is de ned as the inability to see anything at all with either eye [10].
The etiology of Visual Impairment varies with different population groups. According to the WHO, the most common cause of Visual impairment n the developing world is untreated Cataracts (43%) and different Ocular diseases secondary to Diabetes Mellitus (24%) WHO, World Health Report [11]. Population-based surveys in Ethiopia reported cataracts as the main cause of blindness. [12,13].The study from Butajira, Ethiopia, indicated that blindness is either preventable or curable in 74% of the cases [13].
Visual impairment has an impingement on oral health through physical, social, or informational barriers related to impairment, medical condition, and associated medical disorders. As a result, visually impaired people are challenged in their daily activities. The effects of blindness are many, but one of the most common is the inability of the individual to maintain Oral health [14].
Few studies have investigated oral health in visually impaired children, most of whom live in Asia and Africa's poorest regions [15]. Poor oral hygiene, gingivitis, and periodontal diseases have been reported among visually impaired children in studies from India [15][16][17], Iran [18].Turkey [19].Sudan [20 -21].Mann et al. suggested it can be due to their inability to visualize the plaque on tooth surfaces resulting in inadequate plaque removal and, therefore, the progression of dental caries and in ammatory disease of the periodontium [15,22].
There is no accessible data in Ethiopia regarding the dental health care and needs of such visually impaired individuals. Therefore, this study aimed to assess the oral health knowledge and related behaviors among visually impaired participants in Addis Ababa, Ethiopia.
The study was carried out over two and half months during autumn 2018 at the Ethiopian National Association for the blind, located in Addis Ababa, the capital city of Ethiopia. Convenience sampling was used for the library attendees of the impaired individuals entering the blind association for those months; 65 subjects of both sexes were volunteers to be involved in the study. Of these, 20 (30.8%) were with low vision, and 45 (69.2%) were totally visually impaired.

Samples and procedures
By using interviewing questionnaires, the interviewers, 4 Dental Surgeons (1 Female, 3 Males) who are taking care of each category of the visually impaired individuals, were asked to collect data from the participants. These interviewers are Dental surgeons who are well trained on no different general health issues. The participants were noti ed of the method and aim of the study and voluntarily participated.
However, they were advised that they could withdraw from the interview at any time. The privacy and con dentiality assured ethical consideration of the discussion with each participant with documented informed consent. The questionnaire was read to participants, and participants' responses were in writing.

Survey instrument
The study was conducted by distributing a pre-coded questionnaire constructed in English by the authors and then translated to local Amharic language to be clearly understood by the interviewers and the study participants. The questionnaire contained questions to assess socio-demographic characteristics, type of blindness. And, several variables related to knowledge of causes of Dental Caries, including tooth cleaning frequency, durations, methods of cleaning, and tooth cleaning tools.

Measurements
Gender was assessed as male and female. The participants were also divided into totally or partially visually impaired; total visual impairment subjects cannot see anything, even light, and partially visually impaired issues have limited vision [23]. The ages were grouped into ≤19 and ≥20 years old. The socioeconomic characteristics were divided into low and high education; low education subjects got their education at the primary school level, and high education subjects got their education at the secondary school and university level. Moreover, the participants were requested to evaluate their knowledge of the causes of dental caries. Caries can occur by improper cleaning; frequently consuming sweets; not visiting a dentist; having weak teeth; having worms in the tooth. A sum index of knowledge about caries was constructed (range 1-5) and reduced to a dummy variable, high expertise and low knowledge based on a Median split. Tooth cleaning tool was measured as Toothbrush; Traditional Chewing stick; both and Rinsing with water.
The frequency of tooth-cleaning using toothbrushes was measured as: less or equal to ≤2 times a day to more than two times a day; and more than three times a week. Brushing methods were assessed by asking "proper brushing, improper or just brushing. Type of brush was assessed as; Smooth medium, hard, and (I don't know)-duration of Brushing assessed as less than 3 minutes; more than 3 minutes.
Frequency of tooth-cleaning using Traditional stick was measured as: less or equal to ≤2 times a day to more than two times a day; and more than three times a week. Brushing methods were assessed by asking "proper brushing, improper or just brushing. Type of brush was assessed as; old, new, soft, and (whatever available). Duration of Brushing assessed as Two dummy variables were constructed yielding <3 min and >3 min.
Furthermore, Preference of Toothbrush and Traditional chewing stick was measured. The toothbrush was assessed as: It cleans appropriately; it is modern; it is comfortable. Traditional chewing stick was assessed as: It cleans properly; affordable, and it is Religious & comfortable.

Statistical analysis
The data were processed and analyzed using the Statistical Package for Social Sciences [24]. Frequency distributions of variables were computed separately for total and partially visually impaired individuals.

Ethical considerations
The study proposal was submitted to the Department of Dentistry for ethical clearance, and written consent was obtained from the director of the blind association. In addition, a consent letter was carefully read to the participants before study commencement by the interviewers (4 Dental Surgeons).
In this concern, it has been stated to the participants that there is no direct bene t of their participation in the study. However, knowledge gained from the study may lead to the establishment of an oral health prevention program for visually impaired people (general population bene ts) and about the con dentiality, that no information about the participants, or provided by them during the research will be disclosed to others without their written consent.

Results
The total participants were 65 individuals, 46 males and 19 females, totally visually impaired were 45, and partially visually impaired were 20, respectively. Their ages ranged from 10 to 65, with a mean age of 27.2 years. Results regarding the percentage distribution and the number of study participants' socio-demographic characteristics and type of visual impairment are summarized in Figure 1.
The knowledge item was divided into causes of caries. A total of 45 (61.3%) totally visually impaired and 20 (72%) partially visually impaired scored high in caries' knowledge, respectively. The results regarding the percentage distribution of the study participants who con rmed speci c causes of dental caries and type of visual impairment are shown in Figure 2.
Percentage distribution (%) and numbers (n) of the study participants, according to frequency, tooth cleaning Tool, Brush type, and type of visual impairment, are summarized. Figure3. Regular tooth brushing (less or equal to ≤2 times a day) was common in blind type groups, 20 (44.4%) totally and 5 (25%) partially visually impaired, respectively. Both types of blindness were equally responded16 (35.5%) totally and 6 (30%) partially visually impaired respectively used improper brushing methods. At the same time, only a few numbers showed proper brushing methods,5 (11.1%) totally and 2 (10%) partially visually impaired, respectively. Duration of toothbrushing for <3min was responded among a totally 20 (44.4%) and 5(25%) partially visually impaired, respectively.
More than two-thirds of toothbrush user participants' primary reason for preferring toothbrush is that it is modern and has superior cleaning property. The numbers and percentages (%) Distribution of the study participants according to frequency, a method of brushing and brush type, and type of visual impairment is as shown in Table 1. It is comfortable 17.7 8 10 2 Regular use of Traditional chewing stick (less or equal to ≤2 times a day) was equally common in blind type groups, 20 (44.4%) totally and 9 (45%) partially visually impaired, respectively. Moreover, 12 (26.6%) totally and3 (15.0%) partially visually impaired respectively was responded by brushing with a traditional stick more than two times a day.
Approximately more than half the number of totally and 22 (55.5%) and 7 (35%) partially visually impaired who used traditional chewing sticks applied the proper brushing technique. In comparison, only a few numbers showed improper brushing 8 (17.7%) totally and 1 (5.0%) partially visually impaired. Whereas a few participants showed, just brushing 6 (13.3%) totally and 4 (8.8%) partially visually impaired, respectively.
A substantial proportion of the totally 24 (53.3%) and 7 (35%) partially visually impaired respectively reported use of Traditional chewing stick for more than 3min. Brushing by Traditional chewing stick less than 3min was responded among totally 12 (26.6%) and 5 (25%) partially visually impaired respectively.
The majority, 32 (71%) totally and 10 (50%) partially visually impaired respectively, gave other reasons for reasonable prices, proper cleaning, comfort, and religion, for preferring traditional chewing stick.
The numbers and percentages (%) Distribution of the study participants according to frequency, method of brushing, duration preference of using a traditional stick and type of visual impairment is as shown in Table 2.

Discussion
The study was conducted to collect data on knowledge and behaviors of the visually impaired, investigate the ndings and initiate preventive oral health education programs.
The study ndings indicate a high proportion of both Totally and Partially visually impaired had correct knowledge, con rming that improper cleaning, frequently consuming sweets, and not visiting a dentist cause Dental caries. Similarly, a study conducted in Saudi Arabia indicated 71.5% total blind and 63.6% partial blinds scored high in the knowledge of caries [25].
A misconception among participants regarding the cause of dental caries signi ed a lack of knowledge about oral cavity and proper oral health.
It was found that worms in the tooth (46.7% totally and 45% partially visually impaired) respectively & having weak teeth (35.6% totally and 65% partially visually impaired) were considered causes of caries.
Furthermore, & Sabililillah 2016 reported that Dental and oral health knowledge in people with visual impairment is less due to lack of education in people with visual impairment, which affects their ability in gaining Oral Health Knowledge [26,27].
The ndings highlighted improper tooth brushing on the majority of the participants even though they were educated; completing at least secondary school. In addition, many visually impaired individuals found maintaining their oral hygiene more di cult due to their lack of vision which is a constraint to understanding and mastering techniques of oral hygiene practices [28].
In Ethiopia, the Traditional Chewing stick, generally called the MEFAKIA, is used by most of the population [29]. It was found that the Mefakia was found to be as effective as the toothbrush in oral cleaning [29]. A considerable number of participants from both totally and partially visually impaired frequently used traditional chewing sticks. This is consistent with a study from Sudan [30] and in line with Olsson's study in Ethiopia [29]. The traditional chewing stick can be recommended for use in Ethiopia since it is lowpriced and customizable. Similar studies reported that wooden chewing sticks are extensively used among African populations for oral cleaning [31 -35].

Limitations of the study
Due to an insigni cant number of female participants in the study, no comparison was made between males and females. However, the authors are aware that the sample population of this report may not be representative of all blind people in Addis Ababa, Ethiopia.

Conclusion
Page 10/16 The present study showed the awareness about the causes of Dental Caries among both in total and partial visually impaired was high.
The study demonstrated insu cient knowledge among the visually impaired about the cause of dental caries. Moreover, the ndings highlighted improper tooth brushing among most participants even though they were educated completing at least secondary school. Traditional chewing stick was an important tooth brushing tool.

Recommendation:
The key to addressing visually impaired people regarding oral health and oral hygiene is effective knowledge delivery; Audio, and Braille Method. The audio method is a method whereby education on oral health is delivered only through sound and without face to face. While, other way is providing knowledge of dental health with the Braille method. Braille Dental Education (BDE) is a learning process in the oral health eld devoted to the visually impaired or a person with a visual disability using Braille. The goal is to teach, train, develop, and accomplish appropriate knowledge and skills to visually impaired individuals to ensure self-reliance on maintaining their oral hygiene and oral health.
The area needs further exploration to investigate the knowledge and behaviors of visually impaired people in Ethiopia.
This area of research deserves a more extensive investigation that will include more individuals and a dental examination.   Please See image above for gure legend.