Australian Dental Journal
The official journal of the Australian Dental Association
Australian Dental Journal 2013; 58: 483–490 doi: 10.1111/adj.12109
Clinical efficacy of a herbal dentifrice on dentinal hypersensitivity: a randomized controlled clinical trial M Kumari,* SB Naik,† NS Rao,* SS Martande,* AR Pradeep* *Department of Periodontics, Government Dental College and Research Institute, Bangalore, India. †Department of Conservative Dentistry and Endodontics, Government Dental College and Research Institute, Bangalore, India.
ABSTRACT Background: Dentinal hypersensitivity is a common problem and there is a growing interest in herbal based formulations for the treatment of oral diseases. This study was conducted to assess the efficacy of a commercially available novel herbal dentifrice in reduction of dentinal hypersensitivity. Methods: A total of 73 subjects (38 males and 35 females; aged 25–60 years) were randomly divided into two groups: Group 1 – a placebo dentifrice (The Himalaya Drug Company Research and Development, Makali, Bangalore) and Group 2 – (test group), a commercially available herbal dentifrice (Hi Ora K, The Himalaya Drug Company Research and Development, Makali, Bangalore). Sensitivity scores for controlled air stimulus and cold water were recorded at baseline, 6 weeks and 12 weeks. Results: The test group was found to be significantly better compared to the placebo group at the end of 6 and 12 weeks in reduction of dentinal hypersensitivity. Conclusions: The novel herbal dentifrice can be recommended for treatment of dentinal hypersensitivity. Keywords: Clinical trial, dentifrice, dentine desensitizing agents, potassium nitrate, Spinacia oleracea. Abbreviations and acronyms: ANOVA = analysis of variance; DH = dentine hypersensitivity; VAS = visual analog scale. (Accepted for publication 21 December 2012.)
INTRODUCTION Dentinal hypersensitivity (DH) is a characteristic pain arising from exposed dentine, typically in response to various stimuli such as thermal, evaporative, tactile, osmotic or chemical, which cannot be attributed to any other form of dental defect or pathology.1 Dentine hypersensitivity is a common problem which affects 8% to 57% of the adult dentate population and peaks during the third and fourth decades of life.2–4 Any tooth and tooth surface can be affected but dentine hypersensitivity has a predilection for the buccal cervical regions of canines and premolars.5 According to Bissada6 and Narhi et al.,7 when constantly present over a long time, DH can provoke chronic discomfort and emotional distress. In addition, it can make dental plaque control difficult. According to hydrodynamic theory by Braennstroem and Astroem, enamel or cementum loss in cervical areas and the consequent opening of dentinal tubules to the oral environment, under certain stimuli, allows the movement of dentinal fluid inside the tubules, indirectly stimulating the extremities of the pulp nerves, causing pain.8 It was also found that open © 2013 Australian Dental Association
dentinal tubules serve as pathways for the diffusive transport of bacterial elements in the oral cavity to the pulp, which may cause a localized inflammatory pulpal response.9 Microscopic examination reveals that patent dentinal tubules are more numerous and wider in hypersensitive dentine than in non-sensitive dentine.10 The aetiology of dentine hypersensitivity is multifactorial and results from dentine exposure and the opening of dentinal tubules.2 DH can manifest when dentine is exposed by enamel loss by abrasion, erosion or corrosion, or loss of cementum by brushing or periodontal treatment,11 or more commonly, by the association of two or more of these factors.12,13 Agents for topical relief of dentine hypersensitivity either block the exposed dentine tubules or have a direct desensitizing effect on the pulpal nerve fibres.14,15 Treatments can be self-administered by the patient at home or applied by a dental professional in the dental office.11 Various strategies have been used in the treatment of DH which include lasers, iontophoresis, dentine sealers and soft tissue grafting.16 Toothpastes are the most widely used dentifrices for delivering over-the-counter desensitizing agents.11 483
M Kumari et al. The use of potassium nitrate as an effective desensitizing agent dates backs to the testimonial report of Hodosh in 1974.17 Since then, many pastes containing potassium chloride or potassium citrate have been made available.18 It has been found that a single application of a 3% potassium oxalate gel resulted in a significantly higher reduction of DH at 14 and 21 days, when compared to the placebo.19 However, to the best of our knowledge, there are no studies evaluating the effects of herbal based formulations containing potassium nitrate on dentinal hypersensitivity. In vitro studies have shown that phytocomplexes derived from rhubarb stalks (Rhubarb rhaponicum) and spinach leaves (Spinacia oleracia) used in different formulations, can be effective for topical treatment of dentinal hypersensitivity. These phytocomplexes reduced dentinal permeability by occluding dentinal tubules through the formation of calcium oxalate crystals.20 Recently there has been a growing interest in natural products, and herbal based toothpastes have been found as effective as the conventionally formulated dentifrice in the control of plaque and gingivitis.21 Herbal formulations have also been found to be effective in the prevention of dental caries.22,23 However, to our knowledge there has been no study evaluating a herbal dentifrice containing potassium nitrate and Spinacia oleracia on DH. This was the first study which was conducted to assess and compare the efficacy of a commercially available novel herbal dentifrice containing potassium nitrate and Spinacia oleracia on DH compared to a placebo over a period of 12 weeks. MATERIALS AND METHODS This study was a single-centre, longitudinal, triple masked (investigators, individuals and statistician), randomized parallel-arm design. The study duration was 12 weeks, in which sensitivity scores were measured at baseline, 6 weeks and 12 weeks. The research protocol was initially submitted to the Ethical Committee and Review Board of the Government Dental College and Research Institute, Bangalore, India. After ethical approval was granted, subjects were selected from the outpatient section of the Department of Periodontics, Government Dental College and Research Institute, Bangalore, India. The duration of the study was from February 2012 to July 2012. The study group consisted of two groups: Group 1 – a placebo dentifrice (The Himalaya Drug Company Research and Development, Makali, Bangalore, India) and Group 2 – (test group), a commercially available herbal dentifrice (Hi Ora K, The Himalaya Drug 484
Company Research and Development, Makali, Bangalore, India). Each gram of test group dentifrice contained 2.5 mg Cinnamomum zeylanicum, 2.5 mg Syzygium aromaticum, 10.0 mg Spinacia oleracea, 6.0 mg Triphala, 4.0 mg Trikatu and 30.0 mg Suryakshara (Potassium nitrate) and 10.0 mg Yashada bhasma (zinc oxide), sodium benzoate, calcium carbonate with sorbitol, glycerine and xanthan gum. The placebo dentifrice contained calcium carbonate, sodium benzoate with sorbitol, glycerine and xanthan gum. The placebo dentifrice did not contain any of the herbal constituents present in the test group. Sample size calculations were based on detecting a difference of 30% reduction in visual analog scale (VAS) scores24 between the test and control groups using a two-tailed significance level of 5% with a 90% power. A total of 100 individuals were assessed for eligibility and based on inclusion and exclusion criteria, randomized and categorized into two groups, each containing 37 individuals in Group 1 (placebo group) and 36 individuals in Group 2 (test group). The randomization process was made externally by the statistical unit using a computer generated random table. Investigators were not involved in the randomization process, nor were they aware of the assigned group in all outcome evaluations. The dentifrice were dispensed in tubes which had a similar cover design with lot numbers to ensure proper masking of the product from the individuals and the examiner (MK). Sixty subjects (33 males and 27 females) were finally considered because 13 failed to follow-up or discontinued the treatment. There were 30 subjects in each group who finally completed the study. Subjects participating in the study were aged 25–60 years. The mean age was not statistically different among groups and ranged from 42.3 years for Group 1 and 41.9 years for Group 2. Subjects who were in good general health could fulfil the scheduled appointment and gave written informed consent to participate were recruited into the 12-week trial. A flow chart of the study is provided in Fig. 1. Inclusion–exclusion criteria The individuals selected at baseline had a history of DH caused by gingival recession or cervical erosion. Subjects were required to have 20 natural permanent teeth and at least two teeth with a VAS score of ≥4 to be included in the study. Teeth with caries, defective restorations, chipped teeth, deep periodontal pockets (probing depth >4 mm), periodontal surgery within the previous six months, and subjects with orthodontic appliances or bridge work that would interfere with evaluation were excluded.25 Subjects were also excluded if there was presence of occlusal overload or © 2013 Australian Dental Association
Herbal dentifrice in dentinal hypersensitivity Assessed for eligibility (n = 100)
Minimum two teeth with VAS score >4 for air and water stimuli examined
Excluded Not meeting inclusion criteria (n = 19) Refused to participate (n = 8)
Randomized (n = 73) by computer generated number sequence Male (n = 38) Female (n = 35)
Allocated to interventionplacebo group (n = 37)
Allocated to intervention test group (n = 36)
Failed to follow-up (n = 4) Discontinued intervention (n = 3)
Failed to follow-up (n = 4) Discontinued intervention (n = 2)
Analysed (n = 30) Excluded from analysis (n = 7)
Analysed (n = 30) Excluded from analysis (n = 6) Fig. 1 Consort flow chart.
occlusal adjustment recently made in the tooth to be studied. Subjects who had undertaken treatment with any product that could influence the DH of the patient in the 30 days prior to baseline were excluded.26 In addition, subjects were also excluded if they were allergic to ingredients used in the study or exhibited any gross oral pathology, eating disorders, chronic disease, pregnancy and lactation, acute myocardial infarction within the past six months, use of pacemaker, uncontrolled metabolic disease, major psychiatric disorder, heavy smoking or alcohol abuse, any systemic disease or any disease requiring repeated or regular analgesia, anti-inflammatory drugs, or antihistamines.25 Sensitivity assessment Controlled air stimulus (evaporative stimulus) and cold water (thermal stimulus) were used to assess tooth sensitivity. Sensitivity was measured using a 10cm VAS score, with the score of zero being a pain-free © 2013 Australian Dental Association
response and a score of 10 being excruciating pain or discomfort. Scoring of tooth sensitivity was done first by using controlled air pressure, from a standard dental syringe at 40 to 65 psi at ambient temperature, directed perpendicularly and at a distance of 1 to 3 mm from the exposed dentine surface while adjacent teeth were protected with gloved fingers to prevent false–positive results.25 The second stimulus for testing tooth sensitivity was done after a period of at least five minutes using 10 ml of ice cold water applied to the exposed dentine surface, keeping the neighbouring teeth isolated during testing by using the operator’s fingers and cotton rolls.25 After recording sensitivity scores at baseline (investigator MK), subjects were randomly given dentifrice by a dental assistant not involved in the study and advised to use it with a soft bristle toothbrush twice a day. Subjects were also directed to refrain from using any other dentifrice or mouthrinse during the trial but were allowed to continue their normal oral hygiene 485
M Kumari et al. practice during the trial period. Intra-examiner calibration was performed on 20 individuals before the study and the intra-examiner agreement was 95.2% (j = 0.905). Apart from the clinical evaluation, a subjective evaluation was also undertaken at each visit, using a questionnaire relating to the taste and flavour of the dentifrice or any adverse effect experienced after use. To check for compliance, participants were asked to return their assigned tubes so that the investigator could verify the amount of dentifrice that was used. Statistical analysis Mean VAS scores and mean SD were calculated from raw VAS scores from all individuals in a treatment group. Mean VAS scores were compared among groups at different time points (baseline, 6 and 12 weeks) and among groups at each time point using one-way analysis of variance (ANOVA). Post hoc pairwise multiple comparisons were done using the t-test and p < 0.01 was taken as significant when detected. Data were statistically analysed using a software programme (SPSS Statistical Package, Version 17.5, SPSS, Chicago, IL, USA). RESULTS Table 1 shows type of tooth included in the study. Mean VAS scores for air stimulus and water stimulus for both groups at baseline, 6 weeks and 12 weeks are shown in Table 2. There was no significant difference in baseline scores in both groups for both air and water stimulus. Intra-group comparison of percentage change in mean sensitivity showed that the test group resulted in significant improvements from baseline to 6 weeks (–33.64%, –44.35%); baseline to 12 weeks (–45.79%, –57.74%) and between 6 weeks and 12 weeks (–18.31%, –24.06%), to both air and water stimulus (Table 3). Negative value in all percentage change in sensitivity scores showed that there was a reduction in sensitivity score from baseline to 6 and 12 weeks. Tables 4 and 5 show intergroup Table 1. Types of teeth included in study Types of teeth Upper central incisors Upper lateral incisors Upper canine Lower central incisors Lower lateral incisors Lower canine Upper premolars Lower premolars Upper molars Lower molars 486
Teeth selected by investigators (%) 7.9 9.9 12.5 11.3 12.7 8.1 10.2 11.1 8.5 7.8
Table 2. Sensitivity scores to air and water stimulus in test and placebo groups at all time points Stimulus
Group
Baseline Mean SD
6 weeks Mean SD
12 weeks Mean SD
Air stimulus
Placebo group Test group Placebo group Test group
7.13 1.28
6.67 1.21
6.17 0.99
7.37 1.43
4.87 1.20
3.97 0.93
7.83 1.23
6.97 1.03
6.73 1.08
7.97 1.27
4.43 0.77
3.37 0.67
Water stimulus
comparison of percentage change in air and water sensitivity scores at all time points. There was a significant difference between the test group and the placebo group, for air stimulus and water stimulus at all-time intervals. The percentage change difference was greater for water stimulus at all time points (Tables 3 and 5). On subjective evaluation, all individuals gave positive responses regarding the taste and flavour of both dentifrices and no adverse effects were observed. DISCUSSION The current study compared commercially available herbal dentifrices and placebo. The results of the present study demonstrated a reduction in symptoms of DH for the test product from baseline to 6 and 12 weeks for both measures of sensitivity. There was a remarkable pattern towards reduction of DH with time for both variables during the 12 weeks of the active phase of the study in the test group (Fig. 2 and 3). The test product consisted of the following constituents: Cinnamomum zeylanicum, Syzygium aromaticum, Spinacia oleracea, Triphala, Trikatu and Suryakshara. Cinnamomum zeylanicum has been found to have bactericidal properties and is found to be equally effective against both Gram-positive and Gram-negative organisms. Cinnamaldehyde, the predominant active compound in cinnamon oil, has been found to be a natural antioxidant.27 Extract of Syzygium aromaticum (clove) has been found to exhibit growth-inhibitory activity against Gram-negative anaerobic periodontal oral pathogens, including Porphyromonas gingivalis and Prevotella intermedia.28 Triphala has been found to have similar effects on dental plaque and gingival inflammation compared to chlorhexidine.29 Trikatu has anti-inflammatory properties.30 Yashada bhasma contains zinc and has been formulated into oral health products to control plaque, reduce malodour and inhibit calculus formation.31,32 The components responsible for reducing DH in the test group were Suryakshara (potassium nitrate) and © 2013 Australian Dental Association
Herbal dentifrice in dentinal hypersensitivity Table 3. Paired test: percentage change in mean sensitivity scores for two groups at all time points for both measures of sensitivity Measure of sensitivity
Air stimulus
Groups
Change in mean sensitivity score (%) Baseline to 6 weeks
Baseline to 12 weeks
6 to 12 Weeks
–6.54 –33.64* –11.06 –44.35*
–13.55 –45.79* –14.04 –57.74*
–7.50 –18.31* –3.35 –24.06*
Placebo group Test group Placebo group Test group
Water stimulus
*Statistically significant at p-value
The official journal of the Australian Dental Association
Australian Dental Journal 2013; 58: 483–490 doi: 10.1111/adj.12109
Clinical efficacy of a herbal dentifrice on dentinal hypersensitivity: a randomized controlled clinical trial M Kumari,* SB Naik,† NS Rao,* SS Martande,* AR Pradeep* *Department of Periodontics, Government Dental College and Research Institute, Bangalore, India. †Department of Conservative Dentistry and Endodontics, Government Dental College and Research Institute, Bangalore, India.
ABSTRACT Background: Dentinal hypersensitivity is a common problem and there is a growing interest in herbal based formulations for the treatment of oral diseases. This study was conducted to assess the efficacy of a commercially available novel herbal dentifrice in reduction of dentinal hypersensitivity. Methods: A total of 73 subjects (38 males and 35 females; aged 25–60 years) were randomly divided into two groups: Group 1 – a placebo dentifrice (The Himalaya Drug Company Research and Development, Makali, Bangalore) and Group 2 – (test group), a commercially available herbal dentifrice (Hi Ora K, The Himalaya Drug Company Research and Development, Makali, Bangalore). Sensitivity scores for controlled air stimulus and cold water were recorded at baseline, 6 weeks and 12 weeks. Results: The test group was found to be significantly better compared to the placebo group at the end of 6 and 12 weeks in reduction of dentinal hypersensitivity. Conclusions: The novel herbal dentifrice can be recommended for treatment of dentinal hypersensitivity. Keywords: Clinical trial, dentifrice, dentine desensitizing agents, potassium nitrate, Spinacia oleracea. Abbreviations and acronyms: ANOVA = analysis of variance; DH = dentine hypersensitivity; VAS = visual analog scale. (Accepted for publication 21 December 2012.)
INTRODUCTION Dentinal hypersensitivity (DH) is a characteristic pain arising from exposed dentine, typically in response to various stimuli such as thermal, evaporative, tactile, osmotic or chemical, which cannot be attributed to any other form of dental defect or pathology.1 Dentine hypersensitivity is a common problem which affects 8% to 57% of the adult dentate population and peaks during the third and fourth decades of life.2–4 Any tooth and tooth surface can be affected but dentine hypersensitivity has a predilection for the buccal cervical regions of canines and premolars.5 According to Bissada6 and Narhi et al.,7 when constantly present over a long time, DH can provoke chronic discomfort and emotional distress. In addition, it can make dental plaque control difficult. According to hydrodynamic theory by Braennstroem and Astroem, enamel or cementum loss in cervical areas and the consequent opening of dentinal tubules to the oral environment, under certain stimuli, allows the movement of dentinal fluid inside the tubules, indirectly stimulating the extremities of the pulp nerves, causing pain.8 It was also found that open © 2013 Australian Dental Association
dentinal tubules serve as pathways for the diffusive transport of bacterial elements in the oral cavity to the pulp, which may cause a localized inflammatory pulpal response.9 Microscopic examination reveals that patent dentinal tubules are more numerous and wider in hypersensitive dentine than in non-sensitive dentine.10 The aetiology of dentine hypersensitivity is multifactorial and results from dentine exposure and the opening of dentinal tubules.2 DH can manifest when dentine is exposed by enamel loss by abrasion, erosion or corrosion, or loss of cementum by brushing or periodontal treatment,11 or more commonly, by the association of two or more of these factors.12,13 Agents for topical relief of dentine hypersensitivity either block the exposed dentine tubules or have a direct desensitizing effect on the pulpal nerve fibres.14,15 Treatments can be self-administered by the patient at home or applied by a dental professional in the dental office.11 Various strategies have been used in the treatment of DH which include lasers, iontophoresis, dentine sealers and soft tissue grafting.16 Toothpastes are the most widely used dentifrices for delivering over-the-counter desensitizing agents.11 483
M Kumari et al. The use of potassium nitrate as an effective desensitizing agent dates backs to the testimonial report of Hodosh in 1974.17 Since then, many pastes containing potassium chloride or potassium citrate have been made available.18 It has been found that a single application of a 3% potassium oxalate gel resulted in a significantly higher reduction of DH at 14 and 21 days, when compared to the placebo.19 However, to the best of our knowledge, there are no studies evaluating the effects of herbal based formulations containing potassium nitrate on dentinal hypersensitivity. In vitro studies have shown that phytocomplexes derived from rhubarb stalks (Rhubarb rhaponicum) and spinach leaves (Spinacia oleracia) used in different formulations, can be effective for topical treatment of dentinal hypersensitivity. These phytocomplexes reduced dentinal permeability by occluding dentinal tubules through the formation of calcium oxalate crystals.20 Recently there has been a growing interest in natural products, and herbal based toothpastes have been found as effective as the conventionally formulated dentifrice in the control of plaque and gingivitis.21 Herbal formulations have also been found to be effective in the prevention of dental caries.22,23 However, to our knowledge there has been no study evaluating a herbal dentifrice containing potassium nitrate and Spinacia oleracia on DH. This was the first study which was conducted to assess and compare the efficacy of a commercially available novel herbal dentifrice containing potassium nitrate and Spinacia oleracia on DH compared to a placebo over a period of 12 weeks. MATERIALS AND METHODS This study was a single-centre, longitudinal, triple masked (investigators, individuals and statistician), randomized parallel-arm design. The study duration was 12 weeks, in which sensitivity scores were measured at baseline, 6 weeks and 12 weeks. The research protocol was initially submitted to the Ethical Committee and Review Board of the Government Dental College and Research Institute, Bangalore, India. After ethical approval was granted, subjects were selected from the outpatient section of the Department of Periodontics, Government Dental College and Research Institute, Bangalore, India. The duration of the study was from February 2012 to July 2012. The study group consisted of two groups: Group 1 – a placebo dentifrice (The Himalaya Drug Company Research and Development, Makali, Bangalore, India) and Group 2 – (test group), a commercially available herbal dentifrice (Hi Ora K, The Himalaya Drug 484
Company Research and Development, Makali, Bangalore, India). Each gram of test group dentifrice contained 2.5 mg Cinnamomum zeylanicum, 2.5 mg Syzygium aromaticum, 10.0 mg Spinacia oleracea, 6.0 mg Triphala, 4.0 mg Trikatu and 30.0 mg Suryakshara (Potassium nitrate) and 10.0 mg Yashada bhasma (zinc oxide), sodium benzoate, calcium carbonate with sorbitol, glycerine and xanthan gum. The placebo dentifrice contained calcium carbonate, sodium benzoate with sorbitol, glycerine and xanthan gum. The placebo dentifrice did not contain any of the herbal constituents present in the test group. Sample size calculations were based on detecting a difference of 30% reduction in visual analog scale (VAS) scores24 between the test and control groups using a two-tailed significance level of 5% with a 90% power. A total of 100 individuals were assessed for eligibility and based on inclusion and exclusion criteria, randomized and categorized into two groups, each containing 37 individuals in Group 1 (placebo group) and 36 individuals in Group 2 (test group). The randomization process was made externally by the statistical unit using a computer generated random table. Investigators were not involved in the randomization process, nor were they aware of the assigned group in all outcome evaluations. The dentifrice were dispensed in tubes which had a similar cover design with lot numbers to ensure proper masking of the product from the individuals and the examiner (MK). Sixty subjects (33 males and 27 females) were finally considered because 13 failed to follow-up or discontinued the treatment. There were 30 subjects in each group who finally completed the study. Subjects participating in the study were aged 25–60 years. The mean age was not statistically different among groups and ranged from 42.3 years for Group 1 and 41.9 years for Group 2. Subjects who were in good general health could fulfil the scheduled appointment and gave written informed consent to participate were recruited into the 12-week trial. A flow chart of the study is provided in Fig. 1. Inclusion–exclusion criteria The individuals selected at baseline had a history of DH caused by gingival recession or cervical erosion. Subjects were required to have 20 natural permanent teeth and at least two teeth with a VAS score of ≥4 to be included in the study. Teeth with caries, defective restorations, chipped teeth, deep periodontal pockets (probing depth >4 mm), periodontal surgery within the previous six months, and subjects with orthodontic appliances or bridge work that would interfere with evaluation were excluded.25 Subjects were also excluded if there was presence of occlusal overload or © 2013 Australian Dental Association
Herbal dentifrice in dentinal hypersensitivity Assessed for eligibility (n = 100)
Minimum two teeth with VAS score >4 for air and water stimuli examined
Excluded Not meeting inclusion criteria (n = 19) Refused to participate (n = 8)
Randomized (n = 73) by computer generated number sequence Male (n = 38) Female (n = 35)
Allocated to interventionplacebo group (n = 37)
Allocated to intervention test group (n = 36)
Failed to follow-up (n = 4) Discontinued intervention (n = 3)
Failed to follow-up (n = 4) Discontinued intervention (n = 2)
Analysed (n = 30) Excluded from analysis (n = 7)
Analysed (n = 30) Excluded from analysis (n = 6) Fig. 1 Consort flow chart.
occlusal adjustment recently made in the tooth to be studied. Subjects who had undertaken treatment with any product that could influence the DH of the patient in the 30 days prior to baseline were excluded.26 In addition, subjects were also excluded if they were allergic to ingredients used in the study or exhibited any gross oral pathology, eating disorders, chronic disease, pregnancy and lactation, acute myocardial infarction within the past six months, use of pacemaker, uncontrolled metabolic disease, major psychiatric disorder, heavy smoking or alcohol abuse, any systemic disease or any disease requiring repeated or regular analgesia, anti-inflammatory drugs, or antihistamines.25 Sensitivity assessment Controlled air stimulus (evaporative stimulus) and cold water (thermal stimulus) were used to assess tooth sensitivity. Sensitivity was measured using a 10cm VAS score, with the score of zero being a pain-free © 2013 Australian Dental Association
response and a score of 10 being excruciating pain or discomfort. Scoring of tooth sensitivity was done first by using controlled air pressure, from a standard dental syringe at 40 to 65 psi at ambient temperature, directed perpendicularly and at a distance of 1 to 3 mm from the exposed dentine surface while adjacent teeth were protected with gloved fingers to prevent false–positive results.25 The second stimulus for testing tooth sensitivity was done after a period of at least five minutes using 10 ml of ice cold water applied to the exposed dentine surface, keeping the neighbouring teeth isolated during testing by using the operator’s fingers and cotton rolls.25 After recording sensitivity scores at baseline (investigator MK), subjects were randomly given dentifrice by a dental assistant not involved in the study and advised to use it with a soft bristle toothbrush twice a day. Subjects were also directed to refrain from using any other dentifrice or mouthrinse during the trial but were allowed to continue their normal oral hygiene 485
M Kumari et al. practice during the trial period. Intra-examiner calibration was performed on 20 individuals before the study and the intra-examiner agreement was 95.2% (j = 0.905). Apart from the clinical evaluation, a subjective evaluation was also undertaken at each visit, using a questionnaire relating to the taste and flavour of the dentifrice or any adverse effect experienced after use. To check for compliance, participants were asked to return their assigned tubes so that the investigator could verify the amount of dentifrice that was used. Statistical analysis Mean VAS scores and mean SD were calculated from raw VAS scores from all individuals in a treatment group. Mean VAS scores were compared among groups at different time points (baseline, 6 and 12 weeks) and among groups at each time point using one-way analysis of variance (ANOVA). Post hoc pairwise multiple comparisons were done using the t-test and p < 0.01 was taken as significant when detected. Data were statistically analysed using a software programme (SPSS Statistical Package, Version 17.5, SPSS, Chicago, IL, USA). RESULTS Table 1 shows type of tooth included in the study. Mean VAS scores for air stimulus and water stimulus for both groups at baseline, 6 weeks and 12 weeks are shown in Table 2. There was no significant difference in baseline scores in both groups for both air and water stimulus. Intra-group comparison of percentage change in mean sensitivity showed that the test group resulted in significant improvements from baseline to 6 weeks (–33.64%, –44.35%); baseline to 12 weeks (–45.79%, –57.74%) and between 6 weeks and 12 weeks (–18.31%, –24.06%), to both air and water stimulus (Table 3). Negative value in all percentage change in sensitivity scores showed that there was a reduction in sensitivity score from baseline to 6 and 12 weeks. Tables 4 and 5 show intergroup Table 1. Types of teeth included in study Types of teeth Upper central incisors Upper lateral incisors Upper canine Lower central incisors Lower lateral incisors Lower canine Upper premolars Lower premolars Upper molars Lower molars 486
Teeth selected by investigators (%) 7.9 9.9 12.5 11.3 12.7 8.1 10.2 11.1 8.5 7.8
Table 2. Sensitivity scores to air and water stimulus in test and placebo groups at all time points Stimulus
Group
Baseline Mean SD
6 weeks Mean SD
12 weeks Mean SD
Air stimulus
Placebo group Test group Placebo group Test group
7.13 1.28
6.67 1.21
6.17 0.99
7.37 1.43
4.87 1.20
3.97 0.93
7.83 1.23
6.97 1.03
6.73 1.08
7.97 1.27
4.43 0.77
3.37 0.67
Water stimulus
comparison of percentage change in air and water sensitivity scores at all time points. There was a significant difference between the test group and the placebo group, for air stimulus and water stimulus at all-time intervals. The percentage change difference was greater for water stimulus at all time points (Tables 3 and 5). On subjective evaluation, all individuals gave positive responses regarding the taste and flavour of both dentifrices and no adverse effects were observed. DISCUSSION The current study compared commercially available herbal dentifrices and placebo. The results of the present study demonstrated a reduction in symptoms of DH for the test product from baseline to 6 and 12 weeks for both measures of sensitivity. There was a remarkable pattern towards reduction of DH with time for both variables during the 12 weeks of the active phase of the study in the test group (Fig. 2 and 3). The test product consisted of the following constituents: Cinnamomum zeylanicum, Syzygium aromaticum, Spinacia oleracea, Triphala, Trikatu and Suryakshara. Cinnamomum zeylanicum has been found to have bactericidal properties and is found to be equally effective against both Gram-positive and Gram-negative organisms. Cinnamaldehyde, the predominant active compound in cinnamon oil, has been found to be a natural antioxidant.27 Extract of Syzygium aromaticum (clove) has been found to exhibit growth-inhibitory activity against Gram-negative anaerobic periodontal oral pathogens, including Porphyromonas gingivalis and Prevotella intermedia.28 Triphala has been found to have similar effects on dental plaque and gingival inflammation compared to chlorhexidine.29 Trikatu has anti-inflammatory properties.30 Yashada bhasma contains zinc and has been formulated into oral health products to control plaque, reduce malodour and inhibit calculus formation.31,32 The components responsible for reducing DH in the test group were Suryakshara (potassium nitrate) and © 2013 Australian Dental Association
Herbal dentifrice in dentinal hypersensitivity Table 3. Paired test: percentage change in mean sensitivity scores for two groups at all time points for both measures of sensitivity Measure of sensitivity
Air stimulus
Groups
Change in mean sensitivity score (%) Baseline to 6 weeks
Baseline to 12 weeks
6 to 12 Weeks
–6.54 –33.64* –11.06 –44.35*
–13.55 –45.79* –14.04 –57.74*
–7.50 –18.31* –3.35 –24.06*
Placebo group Test group Placebo group Test group
Water stimulus
*Statistically significant at p-value
