Gerodontology

Xerostomia or dry mouth is a condition that is frequently encountered in dental practice. The most common cause is the use of certain systemic medications, which make the elderly at greater risk because they are usually more medicated. Other causes include high doses of radiation and certain diseases such as SjöUgren's syndrome. Xerostomia is associated with difficulties in chewing, swallowing, tasting or speaking. This results in poor diet, malnutrition and decreased social interaction. Xerostomia can cause oral discomfort, especially for denture wearers. Patients are at increased risk of developing dental caries. A thorough intra‐oral and extra‐oral clinical examination is important for diagnosis. Treatment may include the use of salivary substitutes (Biotene), salivary stimulants such as pilocarpine, ongoing dental care, caries prevention, a review of the current prescription drug regimen and possible elimination of drugs having anticholinergic effects. Because of the ageing population, and the concomitant increase in medicated individuals, dentists can expect to be presented with xerostomia in an increasing number of patients in the coming years and therefore should be familiar with its diagnosis and treatment. Therefore, the purpose of this review is to outline for clinicians the common aetiologies, clinical identification, and routine therapeutic modalities available for individuals with xerostomia.

The effects of ageing and dental state on the cross‐sectional area and density of two jaw muscles, the masseter and medial pterygoid, were investigated using computed tomography. The study involved 84 male and 70 female subjects between the ages of 20 and 90 years. The cross‐sectional area of both muscles showed a significant reduction with age; values for female subjects being found in the lower range of the distribution. When consideration was given to the presence or absence of a natural dentition, the cross‐sectional area of both muscles in edentulous subjects showed a greater decease throughout the age range studied. There was a significant decrease in the density of the muscles with increasing age. Previously, this has been interpreted to indicate a progressive increase in fat and fibrous tissue. Subject gender and the absence of teeth appeared to have little effect on this parameter. Changes in the cross‐sectional area and density of these muscles would appear to be consistent with a general age related change of muscle tissue in the body as a whole and may specifically indicate a reduction in the masticatory forces which can be or are being utilised by ageing patients, many of whom have no remaining natural dentition.

Objectives:  The development of a measure, with complimentary normative and perceived needs, for the investigation of functional impairment of individual patients and the investigation of the physical causative bases of impairment.

Subjects:  A consecutive sample of 119 complete denture (CD) wearers attending a Greek department of prosthetic dentistry took part in the study. All subjects presented with some complaint(s) of their dentures.

Method:  Functional assessment of dentures (FAD) criteria and structured questionnaires were used covering denture satisfaction (DS) and food difficulties with CDs. The questions used a five‐point Likert scale.

Results:  The results showed that there were statistically significant associations between satisfaction from dentures and eating specified foods. Statistically significant associations were also found between denture qualities and movement of upper dentures and difficulty eating specified foods, but not with an open question on the difficulty of eating unspecified foods.

Conclusions:  This study successfully validated a suitable model for the combined evaluation of denture quality with clear diagnostic criteria and closed questions on DS and perceived difficulties when eating specified foods. This could predict the need for treatment, monitor the impact of care and provide a feasible measure to meet the need of everyday clinical situations.

Objective:  This study aimed at describing the masticatory handicap of wearing removable dentures measured by some masticatory tests and the intake of hard and soft foods.

Materials and methods:  The subjects were participants in a comprehensive health examination of 67–68‐year‐old men living in Malmö, Sweden. Four hundred eighty‐three men took part in a clinical oral examination which recorded the number of teeth and removable dentures. One hundred and one had complete dentures in both jaws and 131 had removable partial dentures in different combinations. Masticatory tests used almonds to record the number of stokes to the first swallow, and two‐coloured chewing gums for recording bolus kneading and shaping. A nutritionist paid a home visit to assess dietary habits including the consumption of hard and soft foods. The data could be split into groups of different tooth and denture situations which were large enough to enable statistical analysis to be carried out. The results of a regression analysis of the group with different numbers of natural teeth (NT) and no removable dentures could be used as a reference for correlation with the masticatory capacity of removable denture wearers.

Results:  Number of strokes to the first swallow revealed no masticatory limitations of wearing removable dentures, while chewing gum colour‐mixing and shaping revealed more differentiated impairments equivalent to the function of five to 16 teeth in a remaining natural dentition. Hard food intake for the removable denture groups was comparable to 17–19 NT. Soft food intake was not influenced by denture wearing. In a ranking of oral conditions, those with more than 24 NT had the highest test values for all tests, and those with complete sets of dentures the lowest except for the number of strokes to the first swallow of an almond.

Conclusion:  Removable denture wearing can be regarded as a handicap when measured with objective masticatory tests using chewing gum and the intake of hard foods. The number of chewing strokes to the first swallow of an almond and the intake of soft foods is not affected by the wearing of removable dentures.

This article explores the multifactorial relationship between mastication and cognition, with a focus on dementia. Older persons, especially those with dementia, are at great risk of suffering from oral health problems such as orofacial pain and loss of natural teeth. A possible explanation could be that the cognitive and motor impairments resulting from dementia cause a decrease in self‐care and as such, a worsening of oral health. An alternative explanation is that cognition and oral health influence each other. Animal studies show that a decrease in masticatory activity, for example, due to a soft diet or loss of teeth, causes memory loss and neuronal degeneration. The relationship between mastication and cognition has also been researched in human studies, but a cause‐effect relationship has not been proven. It is likely that multiple factors play a role in this relationship, such as self‐care, nutrition, stress and pain.

Objective: The aim of the present study was to investigate whether the maximum bite force (MBF) can be improved by the replacement of complete dentures for elderly people.

Design: Nine edentulous volunteers, mean age 74.2 (± 5.5) years and average denture experience 19.4 ± 19.5 years (1 to 50 years) had replacement dentures made. After a rehearsal session, MBF was recorded with the old dentures, and with the new dentures immediately at insertion, at 3, 8 days, 2–3 weeks, 1, 2, 3 and 6–10 months post insertion (p‐i.). MBF was recorded with the central bearing point method using a full‐bridge strain gauge load cell. Data were analysed off‐line using the mean of two peak readings per patient per session.

Results: The results indicate that MBF tended to be impaired when replacement dentures were first fitted (n.s.). However, this trend reversed during the first month p‐i. for patients with a “moderate” lower ridge resorption of Atwood grade 3 or 4 (n = 5). Patients with more severe lower ridge resorption Atwood grade 5 or 6 (n = 4) showed a significantly lower MBF over the entire observation period (p0.05) and took longer to regain bite strength. Only patients with moderate bone resorption exceeded their pre‐insertion level of MBF within the observation period of 6–10 months p‐i.

Conclusion: The present pilot study suggests that, at least for elderly patients with severe bone resorption, delayed improvement of MBF should be expected with replacement complete dentures.

Although enamel, cementum and dentin all develop carious lesions in roughly the same manner there are significant differences between enamel and the other two tissues. While early enamel lesions are white, root surface lesions in cementum or dentin are light brown or yellow. The color probably arises from extrinsic stain materials, and it is possible that very early, actively forming lesions are colorless. Cementum and dentin often acquire a hypermineralized surface when first exposed to the oral environment. When caries begins to form, this layer can enlarge or disappear. Therefore, it is possible to have lesions with hypermineralized surface layers, hypomineralized surface layers, or no surface layer. Hypermineralization can also occur deeply within a lesion, probably as a result of remineralization. When this occurs the lumen of the tubules fill with mineral and the crystals within the lesion body become larger. Fluoride is readily taken up by carious root tissues and contributes to remineralization. Remineralization of artificial root surfaces after treatment with monofluorophosphate has been shown. In these lesions much of the newly acquired mineral was found near the surface but some was also found in the lesion body.

Background:  Old‐age is the last stage of human evolution and, unfortunately, the ageing of the oral cavity and masticatory system seems accelerated. As a consequence, there is a reduction in the amount of food ingested, which can lead to an imbalance in nutrition.

Objective:  The purpose of this study was to investigate the levels of muscular activation of elderly individuals, during chewing, and to compare with young individuals.

Materials and Methods:  An electromyographical analysis of the masticatory system in 10 individuals aged between 60 and 75 years (elderly group) and a similar number between 23–30 years old (young group ‐ control) was carried out. The analysis was performed using a MyoSystem‐Br1 electromyographer with differential active electrodes. The test was recorded during functional conditions, and the muscles assessed were the temporalis and masseter. Data were normalised by maximum voluntary contraction (MVC), and the results were analysed using an independent t‐test for comparison between the groups.

Results:  The normalised electromyographic data obtained showed significant differences in both groups. Comparing the normalised values obtained for MVC, the mean values for the masseter and temporalis muscles of elderly group were statistically lower (p ≤ 0.05) than control group for harder foods, but there were no significant differences for food with the lowest consistency.

Conclusion:  It can be concluded that elderly individuals show slight hypoactivity of their masticatory musculature during chewing when compared to young individuals.