INTRODUCTION:

Oral cavity is a complex ecosystem which is inhabited by more than 300 bacterial species. Any external interference could disturb the delicate balance between components of microflora in this environment[1]. Fixed orthodontic appliances are an example of such interference. Bonding of brackets usually includes acid etching of enamel, which results in changes in the morphology and chemical nature of the oral cavity.

It has been found that decalcified enamel constitutes good support for adhesion and proliferation of Streptococcus mutans, Veillonella spp, and Actinomyces viscosus. It is also known that living cells easily adhere and colonize polymeric surfaces[2]. Thus, composite resin containing polymers used for attaching brackets to etched enamel provide surfaces are prone to adhesion and growth of microorganism. Moreover, the configuration of fixed appliances promotes retention of food and reduces efficiency of self cleaning by saliva. In effect, fixed dental appliances induce the development and retention of bacterial plaque. Development of dental plaque usually leads to an increase level of caries including bacteria in the oral cavity[3].

Hence, maintenance of good oral hygiene is extremely important during the fixed appliance orthodontic treatment. However, this necessity is challenged by the multibracket fixed appliances that are required for the correction of orthodontic malocclusion[4]. The complex dimension of these brackets potentiates the accumulation of dental plaque around them. Various oral hygiene maintenance practices have been suggested to affect the cleaning ability of the patients. This includes the demonstration of the brushing technique around and between the brackets, various designs of brushes such as the interdental and electric brushes, the use of mouth washes and super floss. Despite of these oral hygiene maintenance instructions, the clinical experience as well as literature[5,6] has shown the accumulation of dental plaque on the teeth. The dental plaque thus accumulated harbor a diverse microflora which produces toxic products and acids. As a result, the tooth structure and the supporting structures are jeopardized whereas the hazards can range from simple gingivitis and white spot lesions to severe interdental bone loss and carious cavitations. It has been estimated that some 60% of dental infections, including gingivitis, white spot lesions, dental caries and periodontal disease are due to microbial biofilms[7]. In addition to the inefficient brushing practices, there are other factors that can affect the plaque accumulation. Some of these factors are related to the clinical practices such as the type of brackets, type of ligation and type of technique . The others are related to the patient socio-demographic factors like , age, gender , diet , frequency of brushing, method of brushing, type of brush, and usage of mouthwash,[8,9] The use of interdental brush, mouthwash and frequent brushing at least twice daily help to reduce the plaque significantly[10]. As there are number of factors that can influence the plaque accumulation around the brackets, therefore, it is rational to know all those factors that can help in reducing the plaque and those which are associated with increased plaque retention. The incorporation of these factors in orthodontic clinical practice and patient education will help to avoid the hazards of dental plaque. Therefore, the objective of this study was to compare the plaque index in patients receiving multi-bracket fixed orthodontic treatment for various factors like, gender, brushing practices, meal habits, types of brackets, types of ligations, use of mouthwash.

MATERIALS AND METHOD:

This was a cross-sectional analytical study carried out at Post Graduate Orthodontic Clinic, Saveetha Dental College. A total number of 40 patient with multi-bracket fixed apliance were randomly selected and diagnosed for the plaque index. The inclusion criteria for the study subject were intact set of teeth and treatment with multi-bracket fixed appliance for at least one month of wear.

Plaque Index (PI) for each subject was recorded according to the Modified Silness and Loe plaque index method. 28 tooth were used to measure the plaque index for the subject. Plaque accumulation was graded as 0=no plaque, 1=mild plaque that is only disclosed with dental probe, 2=moderate plaque around the gingival margin that can be seen with naked eye and 4=abundance of soft debris around the gingival margin and brackets. 4 surface of each tooth were diagnosed for the plaque index. The four surfaces includes buccal, lingual/palatal, labial and proximal suface. The plaque on each of the teeth was graded then summed up and divided by number of tooth present to obtain the plaque index for the subject. The other socio-demographic and clinical practice variables like, gender, meal habits, brushing practice, brushing timings, brushing type, use of mouthwash, type of brackets, and type of ligation were also recorded for study subjects. The data were checked for normality and simple summary statistics were generated. Independent sample t-test was applied to determine the difference in plaque index in factors such as gender, timing of brushing, use of mouthwash, type of brackets, type of ligation ,diet and brushing practice.

RESULTS:

The total sample size of 40 subjects comprised of 18 males (45%) and 22 females (55%). Table I shows the difference in the plaque index for the factors like gender, frequency of brushing, method of brushing, use of mouthwash, eating habits, type of brackets, type of ligation and type of technique. A statistically significant difference is seen in the plaque level among the factors which includes the frequecy of brushing, method of brushing, usage of mouthwash and type of brush used.. The plaque index was lower in subjects who maintaines their oral hygiene by brushing the teeth twice daily. Besides, that, patients who uses interdental brush in addition to the normal brush also shows a lower plaque index. Patients who follows the modified bass brushing technique are also reported with a lower plaque index. In addition to the brushing duration, technique and type of brush used, patient who uses additional dental auxilaries such as mouth wash also shows significantly lower amount of plaque. The subjects who used Begg technique has a slighty higher number of plaque index compare to subjects who used P.E.A technique. The factors like gender, type of brackets, eating habits, type of ligation showed no statistically significant difference in plaque index between the groups.

Table 1 : Difference in plaque index in various factors

Variable		N	Mean	Std. Deviation	Std. Error Mean
Gender
Score	Male	18	1.5717	0.11516	0.02714
Score	Female	22	1.5514	0.1106	0.02358
*Diet*
Score1	Veg	8	1.52	0.0791	0.02797
	Mixed	32	1.5809	0.09219	0.0163
*Frequency*
Score2	Once	24	1.6371	0.07948	0.01622
Score2	Twice	16	1.4594	0.04524	0.01131
*Use of mouthwash*
Score3	Yes	11	1.4373	0.0297	0.00895
Score3	No	29	1.619	0.08958	0.01663
*Type of tooth brush*
Score4	Normal	31	1.6116	0.09107	0.01636
Score4	Ortho	9	1.4311	0.02848	0.00949
*Method of brushing*
Score6	M.Bass	11	1.58761	0.09332	0.01731
Score6	Horizontal	29	1.53	0.0995	0.03
*Type of technique*
Score5	Begg	19	1.6068	0.09849	0.0226
Score5	P.E.A	21	1.5348	0.11527	0.02515
*Type of ligation*
Score7	SS wire	17	1.5424	0.08821	0.02139
Score7	Elastics	23	1.5913	0.10262	0.0214
*Type of bracket*
Score8	Stainless steel	22	1.5745	0.11325	0.02415
Score8	Ceramic	18	1.5517	0.1036	0.02442

Figure 1: Frequency of brushing

Figure 2: Type of ligation used

Figure 3: Type of tooth brush used

Figure 4: Gender

Figure 5: Type of brackets used

Figure 6: Type of technique used

Figure 7: Brushing technique used

Figure 8: Diet consumption

Figure 9: Use of mouthwash

DISCUSSION:

The accumulation of dental plaque around the fixed appliance and oral hygiene maintenance has been the main focus of concern for the researchers. In the present study, it was attempted to address the factors which can affect the plaque around the fixed appliances. The results of this study showed significant difference in Plaque Index for the factors such as type of brushing technique, frequency of brushing, type of brush used and usage of dental auxillaries. The other factors like gender, meal habits, type of brackets, and type of ligation were statistically insignificant.

According to the study done, it concludes that male subjects in the study showed more plaque index levels as compared to females. However, the difference was statistically insignificant. These findings were in accordance with results of study carried out by Grazyna and Joanna, who also showed a higher but insignificant plaque levels for the male subjects[11].

To maintain a proper oral hygiene, patients are generally advised to brush their teeth twice daily. The significance of brushing twice daily is beacuse of the formation of plaque which occurs within a few hours after brushing. Initially, a thin bacteria-free layer is formed within minutes of brushing. This is known as the pellicle formation. Within few hours, bacteria attach to the pellicle and a slime layer is formed around the attached bacteria leading to the plaque formation[12]. Hence, it is advised to brush the teeth twice daily to remove the formation of plaque. Considering the formation of plaque, patient with multi-bracket fixed appliance are instructed about the frequency, method and type of brush to be used after the bracket are placed. Although, oral hygiene instructions are given, 60% of the study subject brushes only once daily and shows a higher number of plaque index compare to the subject who brushes twice daily. In a similar study done by Zafar al Islam, only 30% of the subjects brushes once daily and also shows greater number of plaque index compare to the subject who brushes twice or more than twice daily[13].

During an orthodontic treatment, orthodontist usually prescribe orthodontic brushes or interdental brushes to their patients. This is because using an conventional brush during orthodontic treatment does not clean or remove the plaque and debris efficiently due to the complex structure of the brackets and arch wires. Improper removal of plaque around the brackets and behind the archwire leads to demineralization and subsequently white spots [14]. Hence, orthodontic toothbrush is recommended to patient undergoing orthodontic treatment. The design of the orthodontic toothbrush allows it to clean all the tooth surface including aroud the brackets and below the arch wires. In our study, only 22% of the patient uses orthodontic brush and they showed significantly lower number of plaque index compare to the patient who uses conventional tooth brush. Similar findings were also shown by Ariane et al. in their study for the use of orthodontic tooth brush[15].

Dental plaque accumulation is known to be the primary cause of periodontal disease and dental caries [16]. There fore, adequate removal of dental plaque is crucial in preventative dentistry. This is especially important for patients receiving orthodontic treatment, since fixed appliances encourage an increase in plaque accumulation and retention [17]. Numerous interventions have emerged to enhance the removal of dental plaque, which include mechanical, chemical and biological methods. Of all the methods of plaque removal, tooth brushing is the most commonly used, often on a daily basis [18,19]. Therefore, evidence on the most effective manual tooth brushing technique is important to ensure patients are as efficient as possible with the daily removal of dental plaque. According to our research, patient used horizontal brushing technique shows less amount of plaque accumulation compare to modified bass technique even though the difference is not very significant.

In a research done by A Kang, it suggested that the most effective technique for plaque removal for orthodontic patients with fixed appliances, is the horizontal brushing technique compare to the modified bass technique.[20] The modified Bass technique was found to be more effective than the Horizontal technique in improving gingival health [21]. This could be explained by the fact that the Bass technique characteristically targets plaque on the gingival margin and in the sulcus but is unable to clean areas around the fixed appliances. Gingival inflammation and white spot lesions are more prevalent in orthodontic patients [22,23]. Thus, the Bass technique may be beneficial in improving gingival health, but the recommendation of the technique would not be justified if the risk of white spot lesions was to increase.

Besides that, in this study, we found there is significant difference in PI for the use of mouthwash. It should be noted that the levels of plaque were reduced in subjects who were using mouthwash.. Mouthwash is classified under chemical plaque control and can be either organic or inorganic chemicals which inhibit the accumulation, growth and survival of microbiota and debris[24]. The golden standard adjunct used to control in the removal of plaque is chlorhexidine. According to a study done by A Arundhathi, there is a significant reduction in plaque index in patient using chlorhexidine mouthwash[25]. Hence, patients undergoing orthodontic treatment can be advised to use mouthwash as an extra method to maintain the oral hygiene.

Besides, physical maintainance of oral cavity, clinical practices also plays a role in plaque accumulation. Two different group are formed based in the type of ligation used and their effect on plaque accumulation. The subjects in whom elastics ligatures were used for ligation showed a slightly increase level of plaque as compared to the stainless steel ligatures. However there is no significant difference in the plaque index between stainless steel ligature and elastomeric ligature. A study is done by Alves de Sauza, by placing elastomeric ring on 1 side of the midline and stainless steel ligature on the opposite side. On comparing the plaque index on both the side, it shows that elastomeric ligatures tends to accumulate more plaque compare to stainless steel ligature which is accordance to our study[26]. This results are also similar to another study done by Turkkahraman[27].

The ceramic brackets have been shown in studies to accumulate more plaque as compared to the stainless steel brackets[28]. However, in this study there was no significant difference in PI between the two type of brackets. A more recent and controlled study have shown a significantly lower amount of biofilm on ceramic brackets than on stainless steel brackets[29]. This may be due to the fact that the subjects with ceramic brackets are more conscious about the esthetics and oral hygiene. In a similar study done by M.S.R Seethalan, the results shows no significant difference present in plaque accumulation in different brackets system which is same as our study[30].

In clinical practice, the decision of bracket selection is more dependent on the basis of oral hygiene maintenance rather than the type of brackets. Duration of treatment in our study was also insignificant in relation to the amount of plaque. This means that if the brushing practices are exercised precisely and regularly, then the amount of plaque can be kept at minimum no matter how long the duration of treatment extends.

CONCLUSION:

In conclusion, it proves that the maintenance of good oral hygiene during fixed orthodontic treatment is more dependent of the brushing practices and less on the clinical practices. The subjects who comply with the use of normal and interdental brushing, the timing of brushing and frequency of brushing is less prone to plaque accumulation. Therefore, patients education on oral hygiene maintenance must be a part of the orthodontic treatment. For these reasons, proper methods of instructions in the form of verbal, brochures and video tapes must be devised and incorporated in clinical practice.

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Received on 26.03.2018 Modified on 12.05.2018

Research J. Pharm. and Tech 2018; 11(8): 3445-3450.

DOI: 10.5958/0974-360X.2018.00636.4