Clinical Usefulness of an Oral Moisture Checking Device (Mucus )

Transcription

1 Prosthodont Res Pract 5 : , 2006 ORIGINAL ARTICLE Clinical Usefulness of an Oral Moisture Checking Device (Mucus ) Fumi Takahashi, DDS, PhD, Mutsumi Takahashi, DDS, Shuji Toya, DDS, PhD, Toshiaki Koji, DDS, PhD, and Osami Morita, DDS, PhD Department of Complete Denture, The Nippon Dental University School of Life Dentistry at Niigata, Japan Clinical significance A new oral moisture checking device (Mucus ) has been developed that can measure oral mucosal moisture within 2 seconds. The results of this study suggest that oral mucosal moisture can be measured with the new oral moisture checking device without any inter-operator error. Abstract Purpose: The aim of this study was to investigate the factors that may influence the results of measurements of oral mucosal moisture using the new oral moisture checking device, especially in relation to the operator and the sensor cover. Methods: Oral mucosal moisture was measured using a new oral moisture checking device (Mucus ). To determine the influence of the operator on the measured values by the oral moisture checking device, 5 operators measured the oral mucosal moisture in 12 subjects. The differences were analyzed using the Friedman test. To determine the influence of the sensor cover, one operator measured the oral mucosal moisture in 12 subjects using two sensor covers. The differences were analyzed by Wilcoxon s signed-rank test. Results: The result of the Friedman test revealed the absence of any significant influence of the operator on the measured values of oral mucosal moisture by the oral moisture checking device. The results of the Wilcoxon s signed-rank test revealed that the measured values of oral mucosal moisture by the measuring device differed by about 1.6 % between the two sensor covers (P<0.01). Conclusion: The results of this study suggest that oral mucosal moisture can be measured using the new oral moisture checking device without any interoperator error. However, there is some possibility of the measured values differing depending on the sensor cover used. Corresponding to: Dr Fumi Takahashi Department of Complete Denture, The Nippon Dental University School of Life Dentistry at Niigata, 1-8 Hamaura-cho, Niigata City, Niigata , Japan Tel: , Fax: Key words: dry mouth, oral moisture checking device, reliance Introduction With the aging of society, the number of patients encountered with xerostomia 1 is increasing. Xerostomia is characterized by a decrease in the salivary secretion associated with symptoms pertaining to the oral cavity or the pharynx. 2-8 Symptoms related to oral dryness include a subjective sensation of oral dryness, a feeling of something being wrong in the oral cavity, pain sensation in the oral mucosa, difficulty in mastication, difficulty in swallowing and alteration of taste, etc. Therefore, it is necessary to clinically assess the severity of oral dryness in patients with xerostomia, and an easy examination method for oral dryness which can be performed without the influence of the oral function or systemic condition is required. 9,10 The usefulness and ease of use of an oral moisture checking device (Moisture-Checker-for-Mucus, Scalar Co., Tokyo, Japan) that can measure oral mucosal moisture within 2 seconds has been confirmed. 11 A new oral moisture checking device (Mucus, Life Co., Saitama, Japan) with improved measurement precision was launched in the market in the year 2004, in which the measuring pressure is controlled at a fixed value. However, all the features of the new oral moisture checking device have not yet been clarified in detail. The aim of this study was to investigate the factors that can influence the results of measurement by the new oral moisture checking device, especially in relation to the operator and the sensor cover, and to examine the usefulness of the new oral moisture checking device. Received on August 4, 2006 / Accepted on September 10,

2 Examination for Oral Dryness a b e c d Fig. 1 Measurement of the oral mucosal moisture. a: Oral moisture checking device (Mucus ), b: Fitting of the sensor cover, c: Measurement at the lingual mucosa, d: Measurement at the buccal mucosa, e: Indication of the measurement value. Materials and methods The oral mucosal moisture was measured using the new oral moisture checking device (Mucus, Life Co., Saitama, Japan). The measurement was performed by placing a sensor cover over the sensor of the device, and then bringing the sensor into vertical contact with the oral mucosa until the surface of the sensor goes down fully, where the measuring pressure is controlled at about 200 mg. The measured areas were the lingual mucosa (surface of the tongue 10 mm from the apex linguae) (LM) and buccal mucosa (10 mm from the angle of the mouth) (BM). LM and BM were chosen as the measurement points because many patients complain of oral dryness at these sites, and they lend themselves to easy measurements. For measurement of the moisture in the LM, the subjects were asked to put their tongue out, and for the measurement in the buccal mucosa, the outside of the cheek was supported by the operator s finger (Fig. 1). The measurements were conducted three times, and the mean value was calculated. The subjects of the study were 12 healthy adults (7 males, 5 females, mean age; 23.6±1.1 years old). To determine the influence of the operator on the measured values of oral moisture by the oral moisture checking device, 5 operators measured the oral mucosal moisture in the 12 subjects. The sensor cover was not changed during the measurements in the same subject. The mean oral mucosal moisture value in the healthy adults was then calculated. The variability of the measured values among the operators was analyzed by the Friedman test. To determine the influence of the sensor cover on the measured values of oral mucosal moisture by the oral moisture checking device, one operator measured the oral mucosal moisture of the 12 subjects using two sensor covers. After the measurements using the two sensor covers, the measured values using the two sensor covers were compared. The sensor cover which yielded the higher oral mucosal moisture value was called cover 1, and the other one was called cover 2. The mean oral mucosal moisture values obtained the cover 1 and cover 2 were calculated. The difference in the values obtained with the two sensor covers was analyzed using Wilcoxon s signedrank test. These examinations were performed at a particular time, that is, more than 2 hours after a meal. 215

3 Takahashi et al., Prosthodont Res Pract 5 : , 2006 Fig. 2 The mean oral mucosal moisture value in healthy adults. Results The mean value of oral mucosal moisture in the healthy adults was 32.5±2.0% at the LM and 34.5±1.2% at the BM; the difference in the values measured between LM and BM was statistically significant (P<0.05) (Fig. 2). The mean values of oral mucosal moisture measured by the five operators in each subject are shown in Figure 3. The results of analysis by the Friedman test revealed the absence of any significant influence of the operator on the measured values of oral mucosal moisture by the oral moisture checking device. The mean values of oral mucosal moisture measured using cover 1 or cover 2 are shown in Figure 4. The measured values using the two sensor covers differed by about 1.6%. The results of the Wilcoxon s signed-rank test revealed a significant difference in the measured values of oral mucosal moisture between the two sensor covers (P<0.01). Discussion The oral moisture checking device (Moisture- Checker-for-Mucus ) was adapted from a skin moisture checking device, already in general use. A new oral moisture checking device (Mucus ) was developed by modification of the Moisture- Checker-for-Mucus. According to the manufacturer, the principle of measurement of oral moisture by the oral moisture checking device is that the moisture of the epithelium is measured as capacitance. The dielectric constant of water is markedly higher than that of other substances; therefore, the percentage of water in the substance can be checked by measuring the dielectric constant of the substance. The oral moisture checking device measures the moisture level of the substance by calculating the capacitance from the dielectric constant of the substance; the moisture of the epithelium is measured to a depth of several tens of micrometers within the area of a centimeter square. In general, an oral mucosal moisture value of over 30% is normal, of 29 to 30% is borderline, of 27 to 29% represents a low level of salivary secretion, 25 to 27% represents an intermediate severity of oral dryness, and 25% or less represents severe oral dryness. 12 The new oral moisture checking device (Mucus ) has some improved features. The sensor is movable, and the measuring pressure is about 200 g when the surface of the sensor goes down completely. Therefore, the measuring pressure is controlled at a fixed value, and the measured values can be expected to be stable. The sensor cover was also improved by making it less easily torn. The result of measurement is indicated after 2 seconds, just as soon as the frequency become stable, and the 5- levels sign is also indicated on the display. This study investigated the factors that may influence the measured values of oral mucosal moisture by the new oral moisture checking device, and examined the usefulness of the new oral moisture checking device. The measurements of oral mucosal moisture were repeated 3 times, and the dispersion of the values obtained by the three measurements was within 1%. The results revealed that the mean value of oral mucosal moisture in the healthy adults was 32.5±2.0% at the LM and 34.5±1.2% at the BM, the value in the BM being higher than that in the LM. The reason for this difference is not yet clear. The measured values of the oral mucosal moisture by the five operators in each subject did not differ significantly. It was suggested that the measured value of the oral mucosal moisture would have reliable even if any operator use the oral moisture checking device. Thus, there was scarcely any inter-operator error, that is, the measurements results were independent of the operator using the device. 216

4 Examination for Oral Dryness a b Fig. 3 The mean oral mucosal moisture values in each subject measured by the 5 operators. a: Measurement at the lingual mucosa, b: Measurement at the buccal mucosa, O1~O5: The operators who measured the oral mucosal moisture values. Fig. 4 The mean oral mucosal moisture values obtained using sensor cover 1 and sensor cover 2. The measured values with the two sensor covers were different. This could be explained by the difference in the thickness of the sensor cover resulting in a difference in the measured capacitance, which in turn, resulted in a difference in the measured values of the oral mucosal moisture between the two sensor covers. It is also possible that the condition of the subjects oral mucosa was different between the two points of measurement. It was difficult to set the examination environment outside of the mouth, therefore the measurements were performed in the mouth. It is thus necessary to investigate the influence of the sensor cover on the environment outside of the mouth. The results of this study suggest that oral mucosal moisture can be examined using the new oral moisture checking device without any interoperator error. The measured values, however, appeared to be affected by the sensor cover used. Therefore, it is recommended that the oral mucosal moisture levels is measured several times in cases of xerostomia. The new oral moisture checking device is a useful device as it is easy to use and there is scarcely any inter-operator error. We intend to examine the relationship between the subjective symptom of oral dryness and the oral moisture level in a future study. Conclusion This study investigated the factors that might influence the measured values of oral mucosal moisture by a new oral moisture checking device, especially the factors related to the operator and 217

5 Takahashi et al., Prosthodont Res Pract 5 : , 2006 the sensor cover. The results of this study revealed the absence of any significant influence of the operator on the measured value of oral mucosal moisture by the oral moisture checking device and that however, the values measured using two sensor covers differed by about 1.6%. References 1. Sreebny LM, Valdini A. Xerostomia. A neglected symptom. Arch Intern Med 147: , Fox PC, van der Ven PF, Sonies BC et al. Xerostomia: evaluation of a symptom with increasing significance. J Am Dent Assoc 110: , Edgerton M, Tabak LA, Levine MJ. Saliva: a significant factor in removable prosthodontic treatment. J Prosthet Dent 57: 57-66, Sreebny LM, Valdini A. Xerostomia. Part 1: relationship to other oral symptoms and salivary gland hypofunction. Oral Surg Oral Med Oral Pathol 66: , Mandel ID. The role of saliva in maintaining oral homeostasis. J Am Dent Assoc 119: , Niedermeier WH, Kramer R. Salivary secretion and denture retention. J Prosthet Dent 67: , Sinclair GF, Frost PM, Walter JD. New design for an artificial salivareservoir for the mandibular complete denture. J Prosthet Dent 75: , Lopez JMP, Bermejo FA. Is there an age-dependent decrease in resting secretion of saliva of healthy persons? A study of 1493 subjects. Braz Dent J 5: 93-98, Walff A, Herscovici D, Rosenberg M. A simple technique for the determination of salivary gland hypofunction. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 94: , Chen A, Wai Y, Lee L et al. Using the modified Schirmer test to measure mouth dryness: a preliminary study. J Am Dent Assoc 136: , Takahashi F, Koji T, Morita O. The usefulness of an oral moisture checking device (Moisture Checker for Mucus ). J Jpn Prosthodont Soc 49: , Takahashi F, Koji T, Morita O. Oral dryness examinations: Use of an oral moisture checking device and a modified cotton method. Prosthodont Res Pract 5: 26-30,