Factors affecting salivary α-amylase levels measured with a handheld biosensor and a standard laboratory assay.

OBJECTIVES: A handheld biosensor for measuring salivary α-amylase (sAA) was developed for convenient on-site measurement. Previous studies reported some discrepancies in sAA levels measured with a biosensor and a standard assay. This study aimed to compare sAA levels measured with three different methods and the factors affecting its levels. METHODS: Thirty-eight participants collected saliva two times for three measurements. First, the collector strip was placed under the tongue for 2 minutes, then the strip was used to measure sAA level on-site immediately (intraoral biosensor; method 1). Then, a participant pooled the saliva for 4 minutes and collected the saliva into the tube which was aliquoted to measure in a laboratory with a handheld biosensor (extraoral biosensor; method 2) and with a standard enzyme kinetic assay (EKA; method 3). Additional experiments were carried out to compare the levels of sAA measured with differences in pooling time and positioning of the collector strip. RESULTS: A high correlation of sAA levels between an extraoral and an EKA measurement (r = 0.989) was observed, while sAA levels measured with an intraoral method showed a significant but weaker correlation with either an EKA (r = 0.475) or an extraoral method (r = 0.436). Saliva pooling time and positioning of the collector strip significantly affected sAA levels. CONCLUSIONS: A handheld biosensor is valid to measure sAA levels extraorally. For an intraoral measurement, pooling time and positioning of the collector strip need to be taken into account.

Exogenous melatonin's effect on salivary cortisol and amylase: A randomized controlled trial.

This study aimed to examine the effect of acute exogenous melatonin administration on salivary cortisol and alpha-amylase (sCort and sAA) as representatives of the HPA axis and the sympathetic nervous system, respectively. A single-dose prolonged-release melatonin (2 mg) or a placebo tablet was given to healthy volunteers (n = 64) at 20:00 h in a crossover design. The saliva was collected at six time points (20:00, 21:00, awakening, 30 min after awakening, 10:00, and 12:00 h) and was measured for sCort, sAA, and salivary melatonin (sMT) levels. Pulse rates and sleep parameters were also collected. Melatonin was effective in improving sleep onset latency by 7:04 min (p = .037) and increasing total sleep time by 24 min (p = .006). Participants with poor baseline sleep quality responded more strongly to melatonin than participants with normal baseline sleep quality as they reported more satisfaction in having adequate sleep (p = .017). Melatonin administration resulted in higher sCort levels at awakening time point (p = .023) and a tendency of lower sAA levels but these were not significant. Melatonin ingestion at 20:00 h resulted in a marked increase in sMT levels at 21:00 h and remained higher than baseline up to at least 10:00 h (p < .001). Melatonin increases sCort levels at certain time point with a tendency to lower sAA levels. These opposing effects of melatonin suggested a complex interplay between melatonin and these biomarkers. Also, the results confirmed the positive acute effect of a single-dose melatonin on sleep quality.

The Use of Coffee Aroma for Stress Reduction in Postgraduate Dental Students.

OBJECTIVES: This study aimed to investigate the potential reduction of academic stress related to a graded oral presentation in postgraduate dental students using coffee aromatherapy. METHODS: Healthy postgraduate dental students in a seminar class were divided into coffee (n = 32) and control (n = 26) groups. There were 3 modes of aroma distribution: personal distribution with a coffee pad attached to a lanyard, a lanyard plus a personal fan for ventilation of the aroma, and the typical method of the diffuser to spread the aroma in the ambient air. Stress markers comprised levels of salivary alpha-amylase (sAA), cortisol (sCort), and chromogranin A (sCgA). Pulse rates were also measured. RESULTS: Levels of sAA increased 176.62% ± 30.26% between pre- and postpresentation in the control group. Inhaling coffee aroma during the presentation period significantly ameliorated sAA increase at 81.02% ± 14.90% (P = .015). sCort levels tended to decrease in the coffee group, but not significantly. Surprisingly, sCgA levels increased more in the coffee group. Also, pulse rates decreased in the coffee group (-2.07 ± 2.81 bpm) and increased in the control group (6.90 ± 3.22 bpm; P = .035). Subgroup analysis did not reveal differences in salivary markers amongst the 3 aroma distribution modes. CONCLUSIONS: Coffee aroma could have an anxiolytic effect on postgraduate dental students, as evidenced by changes in sAA levels and pulse rates. Personal aroma distribution was also a useful and effective mode of aromatherapy.

Toothbrush-Dentifrice Abrasion of Dental Sealants: An In Vitro Study.

OBJECTIVE: This study sought to investigate the toothbrush-dentifrice abrasion of dental sealants. MATERIALS AND METHODS: Weight loss (∆W) and depth loss (∆D) were used as abrasion indicators. Sealant samples from nine products were soaked in dentifrice slurry and abraded by using a toothbrushing machine with a brushing force of 300 g. The mean percentages of ∆W and mean values of ∆D after 24,000 and 48,000 strokes of brushing were compared by using paired t-test. A comparison of these mean values among sealant products was performed by using one-way ANOVA and multiple comparison analysis (Scheffe's test). RESULTS: Abrasive wear was observed in all sealants. Teethmate F-1 (Kuraray Noritake, Tokyo, Japan)-a fluoride-releasing unfilled sealant-exhibited the maximum abrasive wear, with ∆W and ∆D values of 1.14% ± 0.37% and 12.84 ± 4.28 µm, respectively. Delton (Dentsply Sirona, Charlotte, North Carolina, United States), a light-cured unfilled sealant, showed the minimum abrasive wear, with ∆W and ∆D values of 0.41% ± 0.09% and 2.93 ± 1.23 µm, respectively. No statistical differences were observed among unfilled sealants except when compared with Teethmate F-1. Similarly, no differences were observed when comparing among filled sealants and flowable composite. CONCLUSION: Abrasive wear occurred in all sealants after brushing with dentifrice. Almost all unfilled sealants showed less wear compared with both filled sealants and flowable composite. However, the low abrasive values of all sealants after brushing with dentifrice implied that there is no clinical significance to this finding.

Comparison of salivary cortisol, amylase, and chromogranin A diurnal profiles in healthy volunteers.

OBJECTIVE: This study aimed to compare the diurnal patterns of three salivary biomarkers (cortisol, amylase, and chromogranin A), as well as the factors affecting their levels. DESIGN: A total of 110 participants with mean age of 26.93 ± 6.05 years old took part in the study. The saliva was collected at awakening, 30 min after awakening, 10:00, 12:00, 16:00, and 19:00 h. Cortisol, amylase, chromogranin A, and total protein levels were determined. RESULTS: The diurnal patterns of three biomarkers were different with cortisol showing the least variance and chromogranin A showing the highest variance among individuals. Participants with lower BMI exhibited higher cortisol levels (p = 0.044). Age oppositely affected amylase and chromogranin A, as being older was associated with higher amylase (p = 0.029) and lower chromogranin A levels (p < 0.01) even though both markers represent the sympathetic activity. Male participants also showed lower chromogranin A levels than females (p = 0.045). Total protein concentration affected chromogranin A levels only around awakening period but not at other time points suggesting that protein adjustment may not be necessary if the experiment is performed during the day. The afternoon was the period where all three biomarkers showed rather stable levels. CONCLUSIONS: These results illustrate the nature of cortisol, amylase, and chromogranin A patterns throughout the day in a normal physiological state and help in choosing the right condition to perform the experiment with these biomarkers.

Comparative Dissemination of Aerosol and Splatter Using Suction Device during Ultrasonic Scaling: A Pilot Study.

Objective: This study compared the aerosol and splatter diameter and count numbers produced by a dental mouth prop with a suction holder device and a saliva ejector during ultrasonic scaling in a clinical setting. Methodology: Fluorescein dye was placed in the dental equipment irrigation reservoirs with a mannequin, and an ultrasonic scaler was employed. The procedures were performed three times per device. The upper and bottom board papers were placed on the laboratory platform. All processes used an ultrasonic scaler to generate aerosol and splatter. A dental mouth prop with a suction holder and a saliva ejector were also tested. Photographic analysis was used to examine the fluorescein samples, followed by image processing in Python and assessment of the diameter and count number. For device comparison, statistics were used with an independent t-test. Result: When using the dental mouth prop with a suction holder, the scaler produced aerosol particles that were maintained on the upper board paper (mean ± SD: 1080 ± 662 µm) compared to on the bottom board paper (1230 ± 1020 µm). When the saliva ejector was used, it was found that the diameter of the aerosol on the upper board paper was 900 ± 580 µm, and the diameter on the bottom board paper was 1000 ± 756 µm. Conclusion: There was a significant difference in the aerosol and splatter particle diameter and count number between the dental mouth prop with a suction holder and saliva ejector (p < 0.05). Furthermore, the results revealed that there was a statistically significant difference between the two groups on the upper and bottom board papers.

Baseline states of mind differentially affected diurnal salivary stress biomarkers: A preliminary study.

The study aimed to determine how different baseline states of mind in each day (relaxed, ordinary, or stressful) affected the diurnal patterns of three commonly investigated salivary stress biomarkers: cortisol (sCort), alpha-amylase (sAA), and chromogranin A (sCgA). A total of 32 healthy volunteers collected saliva on three different mood days at six time points each day (awakening, 30 min after, 10:00, 12:00, 16:00, and 19:00 h). Pulse rates and subjective feeling of stress using a visual analog scale (VAS) were also recorded. The levels of sCort and sAA were highest on a stressful day at certain time points. The levels of sAA were lowest on a relaxing day in the afternoon. Surprisingly, sCgA levels showed an opposite pattern with the highest level seen on a relaxing day. Of note was that the majority of the participants chose a day during a meditation retreat as their relaxing day and participants practicing mindfulness manifested lower levels of sCort (p = 0.003) and sAA (p = 0.043) at 19:00 h compared with those choosing a general leisure day as their relaxing day. Different states of mind were associated with different courses of salivary stress biomarkers. sCort and sAA are the most reliable markers showing the expected trend with higher levels on a stressful day and lower levels on a relaxing day. While the current result cast doubt on the use of sCgA as a stress marker since it was the only marker that showed the opposite trend compared with those of the other two markers as well as pulse rates and VAS. Furthermore, this is the first study to demonstrate that mindfulness practice might have different effects on these biomarkers from just a general relaxed state of mind.

Differential responses of salivary cortisol, amylase, and chromogranin A to academic stress.

Salivary biomarkers have been widely used to help diagnose stress, anxiety, and/or depression. This study aimed to compare the responses of three commonly investigated salivary stress biomarkers that represent the hypothalamic-pituitary-adrenal activity (cortisol; sCort) and the sympathetic activity (alpha-amylase; sAA and chromogranin A; sCgA), using academic oral presentation as a model of stress. Twenty postgraduate dental students attended the seminar class as presenter and audience. The presenters' performances were evaluated by the instructors suggesting more stress than the audience. The saliva was collected two times: before attending class and after an academic presentation (for presenters) or during the class (for audience). The pulse rates (PR) were also recorded. The results showed that the levels of all three biomarkers, as well as PR, were significantly higher in the presenter group compared with the audience group; however, the changes were most prominent with sCort and sAA (99.56 ± 12.76% for sCort, 93.48 ± 41.29% for sAA, 16.86 ± 6.42% for sCgA, and 15.06 ± 3.41% for PR). When compared between pre-post presentation, the levels of sCgA were not different, while those of sCort and sAA were significantly increased. These results suggest more sensitive reactivity to academic stress of sCort and sAA compared with sCgA and that the response of sCgA did not necessarily follow sAA pattern even though both are claimed to reflect the sympathetic activity. More studies are needed to elucidate the roles of sCgA in stress.

The calming effect of roasted coffee aroma in patients undergoing dental procedures.

Coffee beverage consumption is well-known to exert various health benefits; however, the effects of coffee aroma are rarely explored. This study aimed to investigate the calming effect of inhaling coffee aroma while the patients underwent dental procedures (probing and scaling). Salivary α-amylase (sAA) and cortisol (sCort) levels were measured as proxies of sympathetic nervous system and hypothalamic-pituitary-adrenal axis responses to stress respectively. Blood pressures and pulse rates were recorded. The results showed that undergoing dental procedures could increase sAA and sCort levels of the patients inhaling sham aroma while those inhaling coffee aroma had significantly decreased sAA and sCort levels (40% and 25% differences, respectively). The pulse rates of those inhaling coffee aroma were also lower. Subjective assessment using visual analog scale was in line with objective measures as well. The preference for coffee aroma or the frequency of coffee drinking had no effect on the sAA and sCort responses. This is the first study to provide evidence on the effect of coffee aroma on sAA and sCort levels in patients undergoing dental procedures.

Accidental Swallowing of Dental Objects During Pediatric Dental Care in Thailand.

AIM: Accidental swallowing of dental objects can occur at any time during dental treatment, especially in child patients. Its severity and sequelae can range from minor to life-threatening. The study aimed to find out the occurrence of accidental swallowing and type of swallowed objects regarding pediatric dental treatment in Thailand. MATERIALS AND METHODS: A nationwide questionnaire survey was performed among Thai dentists to anonymously report child patients' accidental swallowing throughout their working experience for up to 10 years. Percentage and frequencies of accidental swallowing in child patients, as well as types of dental objects swallowed, were investigated. Association between factors of the respondents and their experiences was assessed by the logistic regression analysis. RESULTS: Among 408 respondents, 99 respondents [24.26%, 95% confidence interval (CI): 20.10-28.42] had experienced accidental swallowing during pediatric dental treatment. All of them reported ingestion with only one respondent reporting aspiration. Extracted teeth, stainless steel crowns, and rubber cups were top on the list of swallowed items experienced by 11.52%, 8.33%, and 3.92% of respondents, respectively. Dental sharps such as endodontic files and orthodontic wires were reported as well. Dentists with higher educational backgrounds, mostly exposed to more complicated cases, were more likely to experience accidental swallowing (odds ratio of 2.90, 95% CI: 1.61-5.21). CONCLUSION: Our results indicate that accidental swallowing in child patients appeared to occur more frequently than anticipated. Awareness on patient safety of dental professionals and preventive measures against accidental swallowing when dealing with child patients should be greatly emphasized.

Sterility maintenance of reused disposable paper/plastic sterilization pouches in actual clinical practice.

Paper/plastic sterilization pouches are commonly used packaging material for steam sterilization. Reuse of these pouches is a general practice in Thailand despite a single-use recommendation. This study aimed to determine microbial contamination after reusing paper/plastic sterilization pouches in a dental clinic and storage in a closed environment for 6 months. Three hundred and twenty pouches underwent 3 times of clinical use in terms of packaging, autoclave sterilization, handling, and unpacking. A mouth mirror was packed in each pouch to be used in a clinic. After each use, a pouch would be carefully inspected for reusability and undergone packaging, sterilization, handling again. In all steps, sterilization monitoring was rigorously applied. After 3 times of use, a piece of filter paper was placed inside each pouch (instead of a mouth mirror), the pouch was autoclaved and stored in a closed environment for 6 months. Then the filter paper was retrieved for microbial cultivation. A negative control group comprised new pouches containing filter paper without storage and a positive control group comprised pouches with impaired integrity. All samples in both the reuse and the negative control groups had no microbial contamination. All samples in the positive control group showed contamination. These results suggested that reusing paper/plastic sterilization pouches could be a safe practice provided careful monitoring and inspection were employed.

Effects of resterilization and storage time on sterility of paper/plastic pouches.

OBJECTIVES: Paper/plastic pouches are widely used packaging materials for autoclaving medical and dental equipment. Although these pouches are recommended for single use, they are generally reused in Thailand. This study aimed to determine the ability of paper/plastic pouches to maintain sterility after multiple sterilization processes and stored in a closed environment for up to 6 months. MATERIALS AND METHODS: A total of 6720 paper/plastic pouches were divided into four experimental groups: new pouches, 1 time, 3 times, and 5 times resterilized pouches. A piece of filter paper was placed inside each pouch, and the pouch was sealed, sterilized, and stored for up to 6 months. At the end of each storage period, the pouch was opened, and the filter paper was transferred to culture broth for microbial cultivation to determine sterility. Negative and positive controls were also used to validate the procedures. RESULTS: All filter papers in the experimental groups, as well as the negative control group, remained sterile for up to 6 months of storage in a closed environment. On the contrary, all filter papers in the positive control group showed microbial contamination. CONCLUSIONS: In a closed storage condition, the paper/plastic pouches that passed multiple sterilization processes (up to 5 times resterilization) still maintained good barrier efficacy and remained sterile for up to 6 months.

A study on light transmittance through red protective shields modified with different window films.

OBJECTIVES/AIMS: This study aimed to improve effectiveness of red protective shields in filtering unwanted light using window films. MATERIALS AND METHODS: Red protective shields were modified by placing V-Kool (VK), Scotchtint (ST) or Hüper Optik (HP) window films on both sides. Percentage transmittance (%T) of light with a wavelength of 190-990 nm was determined using a double-beam ultraviolet (UV) and visible spectrophotometer. RESULTS: In UV light (190-390 nm) and visible light (430-590 nm) ranges, %T in all modified groups and the control was below 2.5%. An increase in %T was observed at the wavelength of 630 nm, when all the modified shields showed superior effectiveness in light filtration over the control. In the infrared spectrum (700-990 nm), %T in the control was constantly high, ranging from 86 to 91%, compared to %T of 2-38% in all the modified groups, with the application of VK on both sides being the most effective group, followed by a combination of VK and HP. CONCLUSION: This study has introduced an economical and simple, yet highly effective, means of enhancing the efficiency of a red plastic protection shield in filtering unwanted infrared light, thereby additionally providing protection for dental personnel from potential ocular damages.