6.1 NEED FOR THE STUDY
Dental caries is a complex disease which is expressed as an interaction of various factors including host, agent, substrate and time.1 Early childhood caries (ECC) is a particularly virulent variant of human dental caries that may devastate the primary dentition of infants, toddlers and young preschool children.2
The American Academy of Paediatric Dentistry(AAPD) has defined ECC as “the presence of one or more decayed, missing or filled tooth surfaces in any primary tooth in a child 71 months of age or younger”. Severe early childhood caries(S-ECC) is the most damaging form of ECC and has reached near epidemic proportions worldwide regardless of race or ethinicity.3
The etiological factors include excessively frequent bottle feedings, prolonged bottle or breast feeding, the child being put to bed at naptime or at night with a nursing bottle holding milk or a sugar containing beverage. Breast feeding or bottle feeding during sleep will result in pooling of the liquid around the teeth, the salivary flow is also decreased during sleep and the clearance of the liquid from the oral cavity is slowed. Together they provide an excellent media for the growth of microorganisms.4
The current community standard of care for the treatment of S-ECC(Severe early childhood caries) is usually restricted to removal and restoration of carious teeth, application of topical fluoride, counseling regarding decay promoting feeding behaviours and oral hygiene instructions.3
However clinical outcomes for treatment of ECC are poor; nearly 40% of children treated for ECC, even with restorative work done under general anesthesia have shown to develop new carious lesions within 6-12 months post dental surgery.5
Microbiologic studies indicate that ECC is characterized by heavy infection of mutans streptococci(MS) on dental surfaces.6 The pathogenicity of MS is due to its ability to produce acid and sustain acid production at low pH levels that results in demineralization of the calcified structure, formation and use of extra- and intracellular storage polysaccharides that permit microorganisms to continuously produce acid even after dietary carbohydrates have depleted and the formation of water insoluble glucans that aid in accumulation of mutans streptococci in plaque.1
Newer methods of managing dental decay in the primary dentition need to be developed as dental surgery has minimum impact on oral MS reservoirs in the setting of S-ECC and counseling regarding decay promoting feeding behaviours by dental clinicians for the most part has not been successful.3
Improved clinical outcomes for ECC may be realized by recognizing the infectious nature of this disease and incorporating antibacterial therapy as a part of caries prevention and treatment.5
An antibacterial agent that is effective and also acceptable to young children will be a useful supplement to current strategy for the prevention of caries.
Chlorhexidine is the antimicrobial agent most familiar to dental professionals for the prevention of dental caries in children7 and is also proved to be an important agent in the chemical control of dental plaque.8
The most suitable forms for application of any anti-cariogenic agents are varnishes, which can be applied in interproximal and cervical areas and in fissures and teeth. Varnishes allow application of a sufficient dose and are retained over a longer period of time and minimise the known side effects of staining of the teeth and of a bad taste.10 Chlorhexidine is now available as a varnish and is particularly effective against S.mutans and S.sobrinus.9
Cervitec, a varnish containing chlorhexidine and thymol has been shown to be effective against MS and has not presented side effects.8
Topical application of iodine solutions have also demonstrated suppression of oral MS populations.7 Human and animal studies indicate that topical iodine agents significantly suppress dental levels of MS and it is approved by the Federal Drug Administration for topical skin and mucosa application in children.2
This information supported the concept that topical application of chlorhexidine and povidone iodine agents to the teeth of children at high risk for ECC should reduce the risk for the development of ECC. So the aim of this
study is to test the antimicrobial efficacy of povidone iodine and chlorhexidine on S.mutans, a known etiologic microorganism of ECC and its role in the prevention of ECC .
6.2 REVIEW OF THE LITERATURE
A pilot study was performed to test whether the suppression of dental MS levels would decrease risk for ECC. The study population consisted of 31 subjects. The subjects were randomized into 2 groups. The 15 subjects in the experimental group and the 16 subjects in the control group were evaluated every 2 months during the study period. At each evaluation, the experimental group had 10% povidone iodine applied and control group had placebo applied to their dentition. Treatment failure was defined as the appearance of white spot lesion(s) on any of the primary maxillary incisors (PMI) during the study period. The results showed that the mean duration of observation to treatment failure was 155 days and the mean duration of observation for treatment success was 217 days. The Kaplan-Meier estimate for incidence of treatment failure in the placebo group was 48% over 357 days. Topical antimicrobial therapy reduces risk for the development of ECC in high-risk children.6
A study to determine whether Cervitec-a chlorhexidine containing varnish could reduce the development of pit and fissure caries was done in children. The subjects included one hundred children in age groups 7-8 and 12- 14 years. To be included in the study each child had to have atleast two sound
contralateral first or second permanent molars with deep fissures. The left or right side was selected randomly for test or control. The plaque samples from the occlusal surfaces of the test and control and the saliva samples were collected at baseline examination and after nine months to estimate the number of S.mutans by the strip mutans method of Jensen and Bratthall. Cervitec varnish containing 1% chlorhexidine and thymol was applied at baseline, at 3-4 months and at 6 months to test the tooth after isolation while the control had prophylaxis using cotton pellet in water each time the varnish was applied to the test tooth. Caries examination of the test and control followed after nine months, according to the criteria of WHO. The results showed that caries increment in both control groups of teeth after nine months is significantly higher than in the test teeth. The rate of caries development in a fissure was significantly correlated to the plaque mutans score of that fissure and there was considerable reduction in the S.mutans count of the plaque in the test teeth compared with the control. Chlorhexidine varnish reduced the development of fissure caries significantly.9
A study was conducted to asses the efficacy of antimicrobial therapy in the prevention of early childhood caries. Eighty three children aged 12 – 19 months were enrolled. The children in the experimental group had 10% povidone iodine applied to their dentition, control children had no treatment. Treatment failure was defined as the defined as the appearance of white spot lesion on any of the maxillary primary incisors during the study period. The results showed that among the participants a 12 month disease free
survival was 91+5% for those receiving treatment and 54+9% for those in the control group. Topical antimicrobial therapy increases disease-free survival in children at high risk of ECC.2
A study evaluated the effect of cervitec on the abundance of mutant streptococci in occlusal dental plaque and on 2- year caries increment on partly erupting first permanent molars. The study population consisted of
sixteen healthy school children 6-8 yrs of age with atleast two sound contralateral partly erupted permanent molars. Stimulated saliva samples were collected at baseline and after one year to evaluate the MS levels.
Cervitec varnish was applied in a split mouth design to one of the teeth at
baseline and after 3 and 6 months, while the other tooth in the same jaw was a control. At three and six months after the first application of varnish a significant suppression of MS was observed in plaque. Caries investigations performed at baseline and every three months during the 2 years after the start of the study showed that all the teeth treated with varnish were free of caries after two years, where as 8/16 control teeth developed incipient caries. Cervitec reduces MS in plaque on erupting permanent molars and can lead to a significant decrease in caries incidence.8
A study was conducted to study the effects of an application of chlorhexidine varnish on dental plaque. The subjects included 40 patients aged 25-34 yrs after undergoing necessary restorative treatment. Half of these patients practiced good oral hygiene; the efforts of the other were poor. Test group
received a chlorhexidine varnish application and the control group received placebo varnish. Initially and after 2 and 6 weeks a modified Dentocult SM-test, bleeding on probing, and a plaque index were recorded. The results showed that in contrast to the control group, improvements in plaque index and bleeding on probing scores were found in patients with poor oral hygiene. The results of Dentocult SM test showed a considerable reduction in Streptococcus colonization. Application of chlorhexidine varnish significantly reduced the quantity of S. mutans colonies significantly and improved clinical parameters in patients with elevated plaque accumulation.10
A study to asses the suppressive effect of 10 percent povidone iodine (PI) coupled with elimination of active carious lesions on salivary mutans streptococci (MS) populations was done in children with severe early childhood caries (S-ECC). Seventy seven children aged 2-5yrs at baseline were enrolled in this study and were treated for S- ECC in one session. 0.2 ml PI solution was applied to the dentition after dental surgery was completed and immediately wiped off. Whole nonstimulated saliva samples were obtained at baseline, at 30 days, 60 days, and 90 days post dental surgery. Samples were placed on ice and processed within 2 hours. The MS level in each sample was expressed as colony forming units (CFUs) per ml of saliva. The results showed that approximately 50 percent of subjects had a >95 percent reduction in CFU/ml of saliva at each time point after baseline. The percentages of subjects with a >50 percent reduction in MS level were 85 percent at 30 days, 83 percent at 60 days, 84 percent at 90 days. PI coupled
with dental surgery has a significant suppressive effect on salivary MS levels in the setting of S-ECC for at least 90 days. Treatment with PI may be an important adjunct to dental surgery for S-ECC.3
AIM AND OBJECTIVE OF THE STUDY:
Aim:
To compare the antimicrobial efficacy of povidone iodine and chlorhexidine on Streptococcus mutans, a known etiologic microorganism of ECC and its role in the prevention of ECC.
6.3 / OBJECTIVES OF THE STUDY
To compare the antimicrobial efficacy of povidone-iodine and chlorhexidine against S.mutans.
To determine the role of antimicrobial therapy in the prevention of ECC in children.
7. / MATERIAL & METHODS
7.1 SOURCE OF THE DATA
Thirty Children with in the age group of 3-6 years reporting to the Department of Pedodontics, K.V.G Dental College and Hospital, Sullia for treatment of ECC will be selected.
7.2 Method of collection of data:
Thirty children will be selected. The children in the study group will be divided into two experimental groups by block randomization.
Group 1: Fifteen children having active carious lesions restored and chlohexidine varnish applied to their dentition.
Group 2: Fifteen children having active carious lesions restored and povidone iodine applied to their dentition.
Written informed consent will be taken prior to the study from their mothers/caretakers.
Inclusion criteria
No medical history.
Presence of full compliment of primary teeth.
Diet chart which reveals exposure to sugar more than four times daily.
The presence of one or more decayed, missing or filled tooth surfaces in any primary tooth in a child 3-6 yrs of age.
Exclusion criteria:
Patients whose parents do not give consent for examination.
Children who do not cooperate for examination.
Children with systemic diseases.
Children who were on antibiotic or medications that might affect oral flora or salivary flow taken within the previous three months.
History of fluoride treatment in the past 3-4 weeks.
ARMAMENTARIUM AND MATERIALS:
1. Diagnostic Instruments: Mouth Mirror, Explorer, Tweezer.
2. Dentocult SM strips
3. Culture media
4. Incubator
5. Magnifying glass
6. Microscope
7. Sterile toothpicks
8. Saliva ejector
9. Cheek retractor
10. Applicator brush
INVESTIGATION DESIGN
30 patients with ECC (3-6yrs of age)
Charting of records, medical and dental
Informed consent will be taken from parents
Collection of saliva and plaque for baseline count of S.mutans
Study patients will be divided into 2 groups
Group 1 Group 2Restoration of active carious lesions Restoration of active carious lesions
Application of povidone iodine. Application of Chlorhexidine
Varnish.
(30 days) (30 days)
(60 days) (60 days)
(90 days) (90 days)
Microbiological assay
Statistical analysis using Students unpaired t test, ANOVA and Bon Feronni t test.
METHODOLOGY
· Written informed consent will be taken prior to the study.· Charting of records-medical and dental by giving a customised proforma to the parents.
· Restoration of active carious lesions will be done for 30 patients.
· The study group will be divided in to two groups.
Group 1: Fifteen patients with S-ECC having active carious lesions restored and chlorhexidine varnish applied to their dentition.