Effect of ozone irrigation and powered toothbrushing on dental plaque, gingival inflammation, and microbial status in institutionalized mentally challenged individuals: A double-blinded, randomized, controlled clinical trial

Abstract

Aim:

This study compares and evaluates the efficacy of ozonated water irrigation (OZI) and powered toothbrushing on the oral health and microbial status of mentally challenged individuals.

Materials and Methods:

Thirty individuals of age range 15–30 years with a mild-to-moderate level of mental retardation (MR) and gingival inflammation participated in this double-blind randomized controlled clinical trial. Total duration of the study was 45 days consisting of two clinical phases (phase I, i.e., aided) and phase II, i.e. unaided) of the duration of 21 days in each phase, with a washout period of 3 days between the two phases. With a split-mouth design, sites from each subject were randomly allocated into two treatment groups: Powered Toothbrushing (PB) and OZI were randomly done for each half side of the mouth of each subject. Subgingival plaque samples were collected from sites of both the treatment groups and sent for microbial analysis. Clinical and microbial parameters were measured before and after the treatment.

Results:

Significant improvement of the clinical and microbial parameters was found in both treatment groups. However, intergroup differences in the parameters were statistically nonsignificant.

Conclusion:

OZI could serve as an alternative or adjunct to powered toothbrushes for people with MR.

INTRODUCTION

Periodontal diseases are inflammatory diseases of the tooth-supporting tissues primarily caused by dysbiotic microbial complex present in dental plaque biofilm. The clinical features of periodontal diseases are gingival bleeding, periodontal pocket formation, and subsequent attachment loss that result in loss of periodontal tissue support leading to loss of teeth.[1] Hence, oral health plays the most important role in esthetics, function, and communication and it has strong biological, psychological, and social importance. The quality of life is also gets affected by poor oral health.[2] The control and elimination of dental plaque formation prevent periodontal disease and also minimize its severity. Toothbrushing is the single most effective method for removing dental plaque for the prevention of periodontal diseases. However, toothbrushing can be a challenging task among some population groups such as people with physical disabilities and mental retardation (MR), since the adequacy of plaque control with toothbrush needs the patient’s compliance. MR is a genetic disorder that is characterized by below-average overall intellectual functioning and deficiency in adaptive behavior.[3] It is one of the highly prevalent developmental disorders, worldwide.[3] The World Health Organization estimates that globally over 450 million people suffer from MR, which accounts for almost 12% of the global burden of disease.[4] Physical inability due to decreased neuromuscular coordination in such individuals makes toothbrushing less effective for them.[5] Moreover, the design of toothbrush also does not allow it to clean all the plaque retentive areas of the tooth since tooth has a complex anatomy. These factors encourage us to search for an alternative strategy for effective plaque removal, especially for people with MR.

Ozone (O₃) is the allotropic form of oxygen. An ozone molecule is made up of three oxygen atoms instead of two as seen in the molecular oxygen (O₂). This extra atom makes ozone highly potent for oxidation. Therefore, ozone gas can be highly effective when used as an antimicrobial agent. It is also capable of stimulating blood circulation and immune response. Ozone shows the highest level of biocompatibility compared to the other commercially available antiseptic agents.[6] Such properties of ozone justify the reason for its widespread use in the field of medicine.[7] In dentistry, ozone is being successfully used for the treatment of many oral diseases. The efficacy of ozonated water against both Gram-positive and Gram-negative oral microorganisms was shown in vitro. Several clinical studies had shown the antimicrobial efficacy against potent periodontopathogens such as Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis (Pg), and Tannerella forsythus.[8-10] Various periodontal inflammatory markers also were shown to be improved with the use of ozone.[11,12] Recent systematic reviews have successfully revealed the antimicrobial properties of ozone.[13,14] Although ozone was proved to be efficacious against bacteria, virus, fungi, and protozoa, very less attention was paid to its use on mentally retarded people. To date, there was no literature available to determine both the clinical and microbiological efficacy of ozone therapy, especially for mentally retarded people. Therefore, the aim of this study was to compare the efficacy of powered toothbrushing and ozonated water irrigation (OZI) for mentally challenged patients.

MATERIALS AND METHODS

Subjects were selected from Asha Kiran School for Special Children, Davangere, Karnataka. Subjects with a mild-to-moderate degree of MR, according to the Stanford‒Binet scale for MR[15] and aged between 15 and 30 years were included for this study. Other inclusion criteria were (i) presence of minimum of 20 teeth, (ii) prebrushing modified Quigley‒Hein plaque index (QPI) score of 1.5 or more,[16] and (iii) mild-to-moderate gingivitis.[17] Patients with history of any antibiotic therapy in the past 6 months and systemic disease were excluded from the study.

This was a double-masked randomized controlled clinical trial using a split-mouth design. Thirty subjects who fulfilled the eligibility criteria were included in the study. Clearance from university as well as the institutional ethics committee was taken and written informed consent was obtained from the guardian of the subjects as well as the principal of the concerned school.

The total duration of our study was 45 days consisting of two clinical phases (phase I and phase II) of duration of 21 days in each phase, with a washout period of 3 days in between two phases. In the phase 1 (aided), the caretaker performed the toothbrushing for the patients.

Caretakers were trained using audiovisual aids and demonstration was done on models as well as on subjects for both procedures. In a split-mouth design, the subjects were divided into two groups. In the powered toothbrushing (PB) group, the toothbrushing was done for one-half side of the mouth of all the subjects using a powered toothbrush (Colgate 360° Sonicpower^®, Colgate-Palmolive, USA) and toothpaste, for 2–3 min daily. In the other group i.e. OZI, the contralateral side was subjected to OZI twice a week. Both of these procedures were continued for 21 days. Then, the patients were given a gap of 3 days of washout period. Phase II (unaided) of our study started next, i.e. on the 25^th day. In this phase, both powered toothbrushing and OZI were performed as described before, except that, here, subjects performed the procedures on their own under the guidance of the caretaker. This was continued for the next 21 days, i.e. till the 45^th day, ensuring the successful completion of the study period [Figure 1]. Both toothbrushing and ozone irrigation were done in the morning session before breakfast between 7.30 a.m. to 9 a.m.

Figure 1.

Schematic representation of the study. OZI – Ozonated water irrigation; PB – Powered toothbrushing

Kent Ozone Dental Jet (Kent Dental Care Products, USA) was used as a device for irrigation. This device had a pressure setting of 350–500 kPa, which resulted in release of ozonated water outflow of 450 ml/h and ozone output of 0.082 mg/h. A 20-gauge blunt needle was attached to the nozzle of the device. The needle was then bent and inserted subgingivally for irrigation. Irrigation was done for 15 s per site, covering six sites in each tooth.

Clinical parameters were recorded and 10–12 sites were selected separately from each quadrant of the mouth for plaque sample collection. A sterile curette (# 5/6 Gracey curette, Hu-Friedy, Chicago, USA) was used to collect the subgingival plaque samples. Samples were then transferred to separate vials containing 41,111 thioglycollate broth transport medium. Vials were closed, labeled, and sent for microbiological analysis for the detection and quantification of four microorganisms, i.e. Prevotella intermedia (Pi), Pg, Actinomyces naeslundii (An), and Fusobacterium nucleatum (Fn).

Clinical parameters, i.e. gingival bleeding index (GBI), QPI, and modified gingival index (MGI) were recorded on four occasions, i.e. before starting of phase I (1^st day), after completion of phase I (21^st day), before starting of phase II (25^th day) and after completion of phase II (45^th day), whereas plaque samples were collected before starting and after completion of the phase I only. Both main investigator and the microbiologist were blinded about the samples and study groups. Clinical and microbiological data were then subjected to statistical analysis thereafter.

Statistical analysis was done using SPSS software (SPSS Inc., IBM, Chicago, USA) version 17 software. Results and proportions were presented as mean ± standard deviation and percentages, respectively. Mann–Whitney U-test and Wilcoxon signed-rank test were used for the comparison of the parameters. P ≤0.05 was considered statistically significant.

RESULTS

Thirty subjects, which included 20 males and 10 females were included in our study. The mean age of the subjects was 22.5 years [Table 1]. Baseline data of clinical and microbial parameters were comparable between the groups. The study period was 45 days.

Table 1.

Demographic data

Variable	Number
Age
Mean age (years)	22.5
Minimum	15
Maximum	30
Gender
Male	20
Female	10

In PB and OZI groups, QPI reduction was 20% and 41%; GBI reduction was 37% and 21%; and MGI reduction was 28% and 38%, respectively. This reduction was significant within each group from 0 to 21 days [Figure 2]. From 21 to 45 days, QPI reduction was 22% and 8%; GBI reduction was 40% and 21%; MGI reduction was 43% and 27%, respectively. This reduction was significant within each group [Figure 3]. When the result was assessed for their overall clinical improvement, i.e. from 0 to 45 days, QPI reduction was 31% and 8%; GBI reduction was 44% and 21%; and MGI reduction was 44% and 27%, respectively [Figure 4]. This reduction was statistically significant within the groups. However, the intergroup comparison was statistically not significant [Table 2].

Figure 2.

Intragroup comparison of the clinical parameters in clinical Phase-I. QPI – Quigley‒Hein plaque index; GBI – Gingival bleeding index; MGI – Modified gingival index; PB – Powered toothbrushing; OZI – Ozonated water irrigation

Figure 3.

Intragroup comparison of the clinical parameters in clinical phase-II. QPI – Quigley‒Hein plaque index; GBI – Gingival bleeding index; MGI – Modified gingival index; PB – Powered toothbrushing; OZI – Ozonated water irrigation

Figure 4.

Intragroup comparison of the clinical parameters from baseline to 45 days. QPI – Quigley‒Hein plaque index; GBI – Gingival bleeding index; MGI – Modified gingival index; PB – Powered toothbrushing; OZI – Ozonated water irrigation

Table 2.

Comparison of clinical parameters

Study groups	Clinical parameters (intergroup mean reduction)
	0-21 days			25-45 days			0-45 days
	QPI	GBI	MGI	QPI	GBI	MGI	QPI	GBI	MGI
PB	0.28±0.31	0.28±0.15	0.45±0.39	0.27±0.34	0.29±0.18	0.68±0.39	0.43±0.37	0.33±0.19	0.70±0.43
OZI	0.55±0.33	0.71±0.11	0.40±0.68	0.55±0.33	0.71±0.11	0.40±0.8	0.55±0.33	0.71±0.11	0.40±0.68
P	0.003 (S)	0.000 (HS)	0.355 (NS)	0.002 (S)	0.002 (S)	0.178 (NS)	0.287 (NS)	0.000 (HS)	0.107 (NS)

P<0.05 was considered statistically significant. QPI – Quigley-Hein plaque index; GBI – Gingival bleeding index; MGI – Modified gingival index; PB – Powered toothbrushing; OZI – Ozonated water irrigation; HS – Highly significant; NS – Nonsignificant; S – Significant; P – Probability value

More reduction in the mean colony-forming unit count was observed in OZI group than in PB group for all the tested microorganisms except An, which was reduced more in PB group [Figure 5]. The CONSORT flow diagram for the study is given in [Figure 6].

Figure 5.

Intragroup comparison of the microbial parameters. PI – Prevotella intermedia; PG – Porphyromonas gingivalis; AN – Actinomyces naeslundii; FN – Fusobacterium nucleatum; PB – Powered toothbrushing; OZI – Ozonated water irrigation

Figure 6.

Flow diagram for split-mouth randomized controlled trial comparing powered brushing with ozone irrigation. n – Number

DISCUSSION

The study was conducted to compare the clinico-microbiological efficacy of powered toothbrushing and OZI in patients with a mild-to-moderate level of MR. Microbial deposits present in dental plaque is the key etiology for periodontal diseases.[18] Mechanical plaque control is considered gold standard and the most common oral hygiene practice for the prevention of periodontal diseases. The effectiveness of toothbrushing depends on several factors like manual dexterity and ability to follow the proper brushing technique. However, limited motor skill due to neurological disturbances makes toothbrushing difficult and ineffective in mentally retarded people.[19] This encouraged us to find an alternative for effective plaque removal, especially for the people with mental disabilities.

The study was done using a split-mouth design. The power of the study increases in this type of study design. The interindividual variabilities were also virtually eliminated when the patient served as his/her own control.[20] Besides, the possibility of cross-over effect usually associated with the split-mouth design was also balanced by a 3 days gap (wash-out period) in between the two clinical phases.

Ozone is the allotropic form of oxygen. It contains an extra atom compared to the oxygen molecule. This extra atom gives more oxidizing capacity, making ozone molecules more efficient in killing microorganisms. Ozone had also been shown to be effective against virus and fungi.[6] Although there are in vitro studies done for the use of ozonated water on oral microorganisms, to date, there is no literature exists on its clinical efficacy for mentally retarded people. Therefore, for the first time, a clinical trial was done to compare the clinico-microbiological effect of ozone therapy in the form of water irrigation and powered toothbrushing for mentally retarded individuals.

In the aided period, i.e. from 0 to 21 days, both powered toothbrushing and OZI were proved to be beneficial in clinical improvement since all the parameters were reduced in both groups. Microbial analysis for the important periodontopathogens, i.e. Pi, Pg, An, and Fn, was done in this period, and the microbial count was significantly reduced in OZI group.[18] This reduction of microbial count can be attributed to antimicrobial properties of ozone. In the follow-up period, i.e. 25^th–45^th day, although clinical parameters were improved significantly in both the study groups, more improvement was seen in PB group than in OZI group. This difference in improvement can be explained by the fact that the follow-up period consisted of unaided toothbrushing. Since the participants were mentally challenged and lacked motor skills, there could be a possibility that they were not able to comply with the proper brushing technique. Besides, there were a few limitations of our study. First, the study was conducted for only individuals with a mild-to-moderate level of MR. Second, assessments of biochemical parameters would have enhanced clinical changes which was not done due to financial restriction. However, no comparative study exists to discuss such results as OZI had been tried for the first time in oral hygiene maintenance of mentally retarded subjects in this study.

CONCLUSION

Within the limitations, the present study confirms the anti-plaque, anti-inflammatory, and antimicrobial effects of ozone in the oral hygiene maintenance of mentally challenged subjects. Hence, ozone therapy in the form of oral irrigation is highly recommended for oral hygiene maintenance of mentally challenged groups. Considering the beneficial effects of ozone and ease of delivery, these forms of therapy could serve as a useful alternative or adjunct to powered toothbrushes. However, further studies are required in this direction.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.