Aim: The consumption of processed starch snack products (PSSPs) has become widespread, raising concerns about their overconsumption and potential impact on overweight-related diseases including dental caries. This narrative review aims to evaluate the evidence linking PSSPs and caries focusing on Japanese PSSPs.

Materials and Methods: We conducted a search in our personal libraries and updated our collection with articles published within the last 20 years that met the predetermined inclusion criteria for a systematic search. In total, we summarised 75 articles.

Results: This review outlined the structure, types, dietary sources and metabolism of starch and discussed the cariogenicity of PSSPs, along with methods for evaluating it and behavioural factors influencing dental caries, such as the frequency and timing of consumption. The cariogenicity of PSSPs was categorised into three aspects: bioavailability, retentive properties and consumption frequency. Studies have demonstrated that combinations of starch and sugar, often found in many PSSPs, exhibited a higher cariogenic potential compared with sugar alone. As dental caries is a complex condition influenced by multiple factors, all of which depend on the individual, the dietary factor itself is also multifactorial and it was divided into two main factors: product and individual related. The latter factor (i.e. how you eat) is more important. For this reason, recent changes in Japanese eating habits, with an increasing preference for PSSPs and a prevalence of unhealthy eating behaviours, may have a negative impact on oral health. In addition, marketing portrays PSSPs as convenient, tasty and quick sources of energy, occasionally adding seemingly healthy ingredients but promoting demineralisation and erosion.

Conclusion: PSSPs are associated with dental caries due to their high bioavailability, long retention on teeth and high palatability. Japanese dental hygienists need to control the caries risk comprehensively and provide patient education on how PSSPs affect overweight-related diseases including dental caries.

There have been many reports about oral function improvement programs aimed at preventing oral frailty implemented in fields such as nursing care prevention classrooms. Notably, it was found that the one-way instructional health education from the profession to the participants occurred more frequently.

This study verified the effectiveness of the Kuchi Building Championship Training Program (KTP) developed by the Good Neighbors Company, based on the hypothesis that participant experience-based oral function training was effective for continuing training and improving oral function. This KTP was developed as a participatory type of program that could be enjoyed like a sport.

The participants were 31 healthy older women (mean age of 70.9 ± 4.0 years), living in Kobe. First, this method required the subjects to participate in the Kuchi Building Championship based on KTP. Subsequently, Kuchi Building Self Training to strengthen tongue movement, jaw opening force, and facial and respiratory muscles was performed at home. The participants were asked to continue with this training for 4 weeks. The training continuation rate was 95.2%.

Data for tongue pressure, jaw opening force, forced vital capacity, and maximum expiratory flow rate was compared before and after the training. The degree of their frailty and the feedback from this program were also investigated. Significant differences were observed in lip pressure, tongue pressure, jaw opening force, forced vital capacity (FVC), and peak expiratory flow rate (PEFR) before and after the training

It was observed that participants enjoyed participating and comments focused on their good impressions.

Based on the above, we concluded that KTP showed the effect of continued training and prevented oral frailty.

The purpose of this study was to examine salivary characteristics, masticatory ability, and oral health-related quality of life (QOL) in elderly people, to compare the results with and without dental checkups, and to clarify the correlation between the risk of periodontal disease and masticatory ability. The test group was 102 elderly persons who has been receiving periodontal maintenance over 2 years, and 30 elderly persons who had not had dental checkups for at least 1 year were the control group. AL-55 was used to investigate the property of saliva, and the following were examined: [Dental Caries] cariogenic bacteria, pH, buffer capacity, [Periodontal disease] blood, leukocyte, protein. The glucose concentration when chewing a gummy jelly for 20 seconds on their habitual chewing side were recorded as masticatory performance. The results showed that compared with the control group, the test group had a lower risk of dental caries and periodontal disease due to salivary pH and salivary protein, and also had a higher Oral Health-Related Quality of Life (OHRQL). It is suggested that periodontal maintenance improved the property of the saliva, suppressed the inflammation of periodontal tissue, and contributed to the improvement of OHRQL.

There was no significant correlation between the masticatory ability and the risk of periodontal disease in the saliva test in the test group, but in the control group, higher masticatory ability was associated with increased inflammation of the periodontal tissue. These results suggest that it is necessary to maintain masticatory ability while maintaining good periodontal condition through periodontal maintenance.

[Purpose] To examine the actual situation and time required for oral health management, we conducted a questionnaire survey on the work in homes and long-term care insurance facilities.

[Materials and Methods] We recruited dental hygienists engaged in oral health management in homes and long-term care insurance facilities to participate in a questionnaire survey. The survey included intervention methods (visiting dental hygiene guidance, guidance for management of in-home medical long-term care, oral hygiene management), age of subjects, nursing care level, history of aspiration pneumonia, presence of enteral nutrition, oral function status, time required (about 20 minutes [20-minute group], about 40 minutes [40-minute group], about 60 minutes or more [60-minute group]), and difficulties in intervention (free description). Text mining was performed for free descriptions.

[Results] Total 168 respondents were recruited to analyze. According to the results of a multinomial logistic regression analysis, the factors that led to the 40-minute group were guidance for management of in-home medical long-term care, visiting dental hygiene guidance, and a history of aspiration pneumonia when the 20-minute group was used as the reference. The factors that led to the 60-minute group were younger age, guidance for management of in-home medical long-term care, and a history of aspiration pneumonia. The difficulties in intervention summarized by AI were “the tongue is dry and moisturizing takes time”, “20 minutes is not enough time for sufficient rehabilitation”, and “sharing care methods takes time”.

[Conclusion] In performing oral health management by dental hygienists, guidance for management of in-home medical long-term care, visiting dental hygiene guidance, or history of aspiration pneumonia were associated with a working time of 40 minutes or more. The difficulties in intervention were a dry tongue, insufficient time for rehabilitation, and sharing care methods taking time.