Effect of Nutritional Guidance on Oral Function in Patients Visiting a General Dental Clinic: A Preliminary Study
Abstract
1. Introduction
2. Materials and Methods
2.1. Participants
2.2. Investigation Items
2.2.1. General and Dental Items
2.2.2. Oral Function Assessment
Oral Moisture Level
Masticatory Performance
Tongue and Lip Motor Function
Maximum Tongue Pressure
Swallowing Function
2.2.3. Body Composition Assessment
2.2.4. Questionnaire Survey on Changes in Dietary Habits
2.3. Nutritional Guidance
- To encourage the inclusion of one protein-containing food item in each of the three meals.
- To encourage conscious nutritional replenishment after engaging in exercise habits such as walking or sports.
- To encourage a balanced diet using the Dietary Variety Score table [24].
2.4. Statistical Analysis
3. Results
4. Discussion
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
Abbreviations
| G group | Guidance group |
| nG group | No guidance group |
| RSST | Repetitive saliva swallowing test |
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| Total | G Group | nG Group | p Value | |
|---|---|---|---|---|
| Participants, n | 38 | 20 | 18 | |
| Age * | 76.0 (69.0–78.8) | 69.0 (62.8–78.0) | 77.0 (75.3–78.8) | 0.069 |
| Male, n (%) | 14 (36.8) | 6 (30.0) | 8 (44.4) | 0.357 |
| Denture wearers, n (%) | 18 (47.4) | 7 (35.0) | 11 (61.1) | 0.107 |
| Number of functional teeth * | 28.0 (28.0–28.0) | 28.0 (27.0–28.0) | 28.0 (28.0–29.0) | 0.234 |
| Number of remaining teeth * | 24.0 (18.3–28.0) | 25.0 (16.5–28.0) | 23.0 (22.3–27.0) | 0.565 |
| Oral function * | ||||
| Masticatory performance | 6.0 (3.3–7.0) | 6.0 (3.8–7.0) | 5.5 (3.5–7.0) | 0.965 |
| Phonation of /pa/, times/s | 6.3 (5.8–6.8) | 6.5 (6.0–6.9) | 5.8 (5.6–6.7) | 0.109 |
| Phonation of /ta/, times/s | 6.1 (5.6–6.6) | 6.2 (5.8–7.0) | 5.9 (5.6–6.4) | 0.123 |
| Phonation of /ka/, times/s | 5.8 (5.4–6.4) | 6.0 (5.6–6.4) | 5.6 (5.0–6.2) | 0.091 |
| Tongue pressure, kPa | 29.9 (26.1–34.4) | 31.5 (27.3–36.5) | 28.3 (24.3–32.9) | 0.169 |
| RSST, n/30 s | 3.0 (3.0–3.8) | 3.0 (2.8–4.0) | 3.0 (3.0–3.0) | 0.447 |
| Oral moisture content | 30.9 (29.1–32.3) | 30.5 (29.3–32.6) | 31.0 (28.5–32.0) | 0.372 |
| Body composition * | ||||
| Body weight, kg | 53.7 (47.4–61.0) | 53.3 (48.2–59.8) | 54.6 (46.7–61.0) | 0.803 |
| BMI, kg/m2 | 21.6 (20.5–23.3) | 21.5 (20.9–23.7) | 22.1 (20.4–23.1) | 0.861 |
| Body fat percentage, % | 28.9 (24.2–33.0) | 29.8 (26.0–33.3) | 26.1 (23.6–32.7) | 0.306 |
| Skeletal muscle mass, kg | 20.5 (17.6–23.2) | 20.5 (18.5–21.5) | 21.5 (17.3–24.7) | 0.474 |
| Fat mass, kg | 14.6 (13.1–18.8) | 14.7 (14.2–19) | 14.4 (11.6–17.8) | 0.430 |
| Fat-free mass, kg | 38.3 (33.5–42.9) | 38.3 (34.3–40.0) | 40.0 (33.3–45.5) | 0.474 |
| Total body water, kg | 28.2 (24.7–31.6) | 28.2 (25.2–29.3) | 29.5 (24.5–33.4) | 0.474 |
| Protein, kg | 7.4 (6.5–8.4) | 7.4 (6.8–7.8) | 7.8 (6.4–8.9) | 0.483 |
| Minerals, kg | 2.7 (2.4–3.0) | 2.6 (2.4–2.9) | 2.7 (2.4–3.1) | 0.396 |
| Basal metabolic rate, kcal | 1197.0 (1094.3–1297.5) | 1197.0 (1110.8–1234.8) | 1232.5 (1089.3–1351.5) | 0.474 |
| G Group | nG Group | Main Effect | Interaction | ||||
|---|---|---|---|---|---|---|---|
| Time | Group | ||||||
| Baseline | 3 Months | Baseline | 3 Months | p Value | p Value | p Value | |
| Masticatory performance | 5.3 ± 2.4 | 6.5 ± 2.4 | 5.4 ± 2.4 | 5.3 ± 2.0 | 0.009 | 0.489 | p < 0.001 |
| Phonation /pa/, times/s | 6.4 ± 0.8 | 6.5 ± 0.5 | 5.9 ± 1.0 | 6.1 ± 0.8 | 0.296 | 0.061 | 0.667 |
| Phonation /ta/, times/s | 6.3 ± 0.8 | 6.4 ± 0.6 | 5.8 ± 0.7 | 5.8 ± 0.8 | 0.226 | 0.024 | 0.491 |
| Phonation /ka/, times/s | 6.0 ± 0.6 | 6.2 ± 0.5 | 5.5 ± 0.9 | 5.6 ± 0.8 | 0.170 | 0.009 | 0.621 |
| Tongue pressure, kPa | 31.4 ± 8.6 | 33.9 ± 7.5 | 28.4 ± 8.2 | 27.8 ± 8.7 | 0.129 | 0.093 | 0.015 |
| RSST, n/30 s | 3.3 ± 1.0 | 4.1 ± 0.9 | 2.9 ± 0.5 | 3.0 ± 0.8 | 0.003 | 0.004 | 0.006 |
| Oral moisture content | 31.0 ± 2.0 | 30.0 ± 1.3 | 30.4 ± 1.9 | 30.4 ± 1.5 | 0.159 | 0.807 | 0.158 |
| G Group | nG Group | Main Effect | Interaction | ||||
|---|---|---|---|---|---|---|---|
| Time | Group | ||||||
| Baseline | 3 Months | Baseline | 3 Months | p Value | p Value | p Value | |
| Body weight, kg | 55.1 ± 11.9 | 55.0 ± 11.9 | 56.2 ± 13.1 | 55.8 ± 13.0 | 0.202 | 0.811 | 0.514 |
| BMI, kg/m2 | 22.2 ± 2.5 | 22.1 ± 2.7 | 22.0 ± 3.1 | 21.8 ± 2.8 | 0.065 | 0.816 | 0.941 |
| Body fat percentage, % | 29.6 ± 5.7 | 29.7 ± 6.0 | 26.9 ± 6.7 | 27.1 ± 6.2 | 0.638 | 0.183 | 0.896 |
| Skeletal muscle mass, kg | 20.7 ± 5.8 | 20.8 ± 5.7 | 22.1 ± 6.0 | 21.9 ± 6.4 | 0.730 | 0.526 | 0.469 |
| Fat mass, kg | 16.5 ± 4.6 | 16.3 ± 5.0 | 15.2 ± 5.4 | 15.1 ± 4.7 | 0.485 | 0.434 | 0.947 |
| Fat-free mass, kg | 38.6 ± 9.6 | 38.6 ± 9.4 | 41.0 ± 9.9 | 40.7 ± 10.7 | 0.587 | 0.491 | 0.460 |
| Total body water, kg | 28.4 ± 7.0 | 28.4 ± 6.9 | 30.2 ± 7.3 | 30.0 ± 7.9 | 0.672 | 0.479 | 0.500 |
| Protein, kg | 7.5 ± 1.9 | 7.5 ± 1.9 | 8.0 ± 2.0 | 7.9 ± 2.1 | 0.613 | 0.527 | 0.424 |
| Minerals, kg | 2.7 ± 0.6 | 2.7 ± 0.6 | 2.8 ± 0.6 | 2.8 ± 0.7 | 0.142 | 0.537 | 0.184 |
| Basal metabolic rate, kcal | 1203.1 ± 207.3 | 1204.2 ± 202.3 | 1254.8 ± 214.0 | 1248.9 ± 230.2 | 0.652 | 0.490 | 0.460 |
| G Group | nG Group | p Value | ||
|---|---|---|---|---|
| Q1. Variety of foods | Increased (markedly/slightly) | 9 | 0 | 0.001 |
| No change Decreased (slightly/markedly) | 11 0 | 16 2 | ||
| Q2. Frequency of meat or fish consumption | Increased (markedly/slightly) | 14 | 0 | p < 0.001 |
| No change Decreased (slightly/markedly) | 6 0 | 15 3 | ||
| Q3. Frequency of vegetable and fruit consumption | Increased (markedly/slightly) | 13 | 0 | p < 0.001 |
| No change Decreased (slightly/markedly) | 7 0 | 18 0 | ||
| Q4. Frequency of chewy foods consumption | Increased (markedly/slightly) | 5 | 0 | 0.048 |
| No change Decreased (slightly/markedly) | 14 1 | 16 2 | ||
| Q5. Frequency of soft food consumption | Increased (markedly/slightly) | 0 | 1 | 0.474 |
| No change Decreased (slightly/markedly) | 20 0 | 17 0 | ||
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Share and Cite
Makita, K.; Ono, T.; Kawamoto, A.; Takahashi, K. Effect of Nutritional Guidance on Oral Function in Patients Visiting a General Dental Clinic: A Preliminary Study. J. Clin. Med. 2026, 15, 23. https://doi.org/10.3390/jcm15010023
Makita K, Ono T, Kawamoto A, Takahashi K. Effect of Nutritional Guidance on Oral Function in Patients Visiting a General Dental Clinic: A Preliminary Study. Journal of Clinical Medicine. 2026; 15(1):23. https://doi.org/10.3390/jcm15010023
Chicago/Turabian StyleMakita, Kazuki, Takahiro Ono, Akiyo Kawamoto, and Kazuya Takahashi. 2026. "Effect of Nutritional Guidance on Oral Function in Patients Visiting a General Dental Clinic: A Preliminary Study" Journal of Clinical Medicine 15, no. 1: 23. https://doi.org/10.3390/jcm15010023
APA StyleMakita, K., Ono, T., Kawamoto, A., & Takahashi, K. (2026). Effect of Nutritional Guidance on Oral Function in Patients Visiting a General Dental Clinic: A Preliminary Study. Journal of Clinical Medicine, 15(1), 23. https://doi.org/10.3390/jcm15010023

