Management of oral sequelae

Acupuncture as an optional treatment for hospice patients with xerostomia: an intervention study

More than 70% of seriously ill patients with cancer suffer from xerostomia and the associated problems of swallowing, chewing and speaking. This study aims to investigate whether treatment with acupuncture is a viable option for hospice patients with xerostomia. During a 2-year period, 117 patients were assessed for xerostomia. Eighty-two patients were found to have moderate xerostomia. Sixty-seven fulfilled the criteria for inclusion. Of these, 14 were included but only eight completed the study. Ten acupuncture treatments were given during a 5-week period. The effect of acupuncture was measured using a visual analogue scale, and by measuring the saliva production before and after the series of treatment. The results show that all the patients experienced alleviation of dryness of the mouth and the associated symptoms, and thus benefited from the acupuncture treatment. However, conducting a 5-week acupuncture intervention study is not feasible at an inpatient hospice due to the patients being too close to death.

Suppression of radiation-induced salivary gland dysfunction by IGF-1

Background

Radiation is a primary or secondary therapeutic modality for treatment of head and neck cancer. A common side effect of irradiation to the neck and neck region is xerostomia caused by salivary gland dysfunction. Approximately 40,000 new cases of xerostomia result from radiation treatment in the United States each year. The ensuing salivary gland hypofunction results in significant morbidity and diminishes the effectiveness of anti-cancer therapies as well as the quality of life for these patients. Previous studies in a rat model have shown no correlation between induction of apoptosis in the salivary gland and either the immediate or chronic decrease in salivary function following γ-radiation treatment.

Methodology/Principal Finding

A significant level of apoptosis can be detected in the salivary glands of FVB mice following γ-radiation treatment of the head and neck and this apoptosis is suppressed in transgenic mice expressing an activated mutant of Akt (myr-Akt1). Importantly, this suppression of apoptosis in myr-Akt1 mice preserves salivary function, as measured by saliva output, three and thirty days after γ-radiation treatment. In order to translate these studies into a preclinal model we found that intravenous injection of IGF1 stimulated activation of endogenous Akt in the salivary glands in vivo. A single injection of IGF1 prior to exposure to γ-radiation diminishes salivary acinar cell apoptosis and completely preserves salivary gland function three and thirty days following irradiation.

Conclusions/Significance

These studies suggest that apoptosis of salivary acinar cells underlies salivary gland hypofunction occurring secondary to radiation of the head and neck region. Targeted delivery of IGF1 to the salivary gland of patients receiving head and neck irradiation may be useful in reducing or eliminating xerostomia and restoring quality of life to these patients.

The dose to the parotid glands with IMRT for oropharyngeal tumors: the effect of reduction of positioning margins

PURPOSE

The aim of this paper is to quantify the importance of the reduction of positioning margins applied to the clinical target volume (CTV) on the dose distribution of the parotid gland for different intensity-modulated radiotherapy (IMRT) strategies for the treatment of oropharyngeal cancer.

METHODS AND MATERIALS

CTVs and organs at risk were delineated in the planning computed tomographic (CT) scans of three patients. Margins of 0, 3, 6 and 9mm were applied to the CTVs in order to obtain the planning target volumes (PTVs). Three IMRT strategies were used to optimize the dose distribution.

RESULTS

The analysis of the three IMRT strategies resulted in: (1) an optimal dose distribution in the PTV; (2) optimal dose distribution in the PTV while sparing the parotid gland and (3) more parotid gland sparing but at expense of the dose homogeneity in the PTV. The mean parotid dose increased linearly with increasing margin by approximately 1.3Gy per mm. As a result, the normal complication probability (NTCP) for xerostomia decreased when smaller margins were applied. Reducing the margin from 6 to 3mm resulted in an NTCP reduction of approximately 20%.

CONCLUSION

Reducing the CTV-PTV margin by improving the patient position accuracy may lead to a significant reduction of NTCP for the IMRT treatment of the oropharyngeal tumors and lymph nodes level II.

Quantitative dose-volume response analysis of changes in parotid gland function after radiotherapy in the head-and-neck region

PURPOSE

To study the radiation tolerance of the parotid glands as a function of dose and volume irradiated.

METHODS AND MATERIALS

One hundred eight patients treated with primary or postoperative radiotherapy for various malignancies in the head-and-neck region were prospectively evaluated. Stimulated parotid flow rate was measured before radiotherapy and 6 weeks, 6 months, and 1 year after radiotherapy. Parotid gland dose-volume histograms were derived from CT-based treatment planning. The normal tissue complication probability model proposed by Lyman was fit to the data. A complication was defined as stimulated parotid flow rate <25% of the preradiotherapy flow rate.

RESULTS

The mean stimulated preradiotherapy flow rate of 174 parotid glands was 0.34 mL/min. The mean flow rate reduced to 0.12 mL/min 6 weeks postradiotherapy, but recovered to a mean flow rate of 0.20 mL/min at 1 year after radiotherapy. Reduction in postradiotherapy flow rate correlated significantly with mean parotid dose. No threshold dose was found. Increasing the irradiated volume of parotid glands from 0%-40% to 90-100% in patients with a mean parotid dose of 35-45 Gy resulted in a decrease in flow ratio from, respectively, approximately 100% to less than 10% 6 weeks after radiation. The flow ratio of the 90%-100% group partially recovered to 15% at 6 months and to 30% at 1 year after radiotherapy. The normal tissue complication probability model parameter TD(50) (the dose to the whole organ leading to a complication probability of 50%) was found to be 31, 35, and 39 Gy at 6 weeks, 6 months, and 1 year postradiotherapy, respectively. The volume dependency parameter n was around 1, which means that the mean parotid dose correlates best with the observed complications. There was no steep dose-response curve (m = 0.45 at 1 year postradiotherapy).

CONCLUSIONS

This study on dose/volume/parotid gland function relationships revealed a linear correlation between postradiotherapy flow ratio and parotid gland dose and a strong volume dependency. No threshold dose was found. Recovery of parotid gland function was shown at 6 months and 1 year after radiotherapy. In radiation planning, attempts should be made to achieve a mean parotid gland dose at least below 39 Gy (leading to a complication probability of 50%).

Clinical trial of a mucin-containing oral spray for treatment of xerostomia in hospice patients

Thirty-five hospice patients complaining of dry mouth entered a double-blind, single-phase placebo-controlled trial of a mucin-containing oral spray (Saliva Orthana) for the relief of xerostomia. The sprays were administered ad libitum for two weeks by the patients themselves, with nursing help as necessary. A detailed history and examination were undertaken, together with collection of microbiological specimens, at entry and after seven and 14 days of spray usage, respectively. Thirty-one patients were available for follow-up at seven days and 26 patients after 14 days. Relief of oral dryness during the day was reported by 9/15 patients on Saliva Orthana and 10/16 patients on placebo by day 7, with a similar degree of improvement maintained to day 14. The corresponding figures by day 7 for relief of dryness at night were 8/15 for Saliva Orthana and 8/16 for placebo. There were no statistically significant differences between those on active and those on placebo spray for any of the oral symptoms recorded. Neither spray had any major impact on the oral microflora. However, the majority of patients in both treatment groups wished to continue using a mouth spray at the end of their involvement in the trial. Whilst the data from this study provide no evidence for increased benefit of a mucin-containing spray over a mucin-free placebo among xerostomic hospice patients, it is clear that both sprays provided worthwhile symptomatic relief of oral dryness for many of the participants.

Current treatment modalities of oral problems of patients with Sjögren's syndrome: caries prevention

Prevention of dental caries in patients with hyposalivation due to Sjögren's syndrome requires increasing host resistance and decreasing cariogenic organisms and their substrate. Although plaque control by scrupulous oral hygiene is important, particularly from a periodontal perspective, and restriction of dietary sucrose intake can limit caries, the most successful therapeutic and preventive measure has been the topical application of fluoride to the tooth surface, by the dentist, dental hygienist, dental auxiliary, and the patient. Studies on schoolchildren with normal salivary function who used fluoride dentifrices have shown that efficacy in caries prevention depends on (1) the concentration of fluoride used, (2) the frequency with which it is applied, and, to a certain extent, (3) the specific fluoride compound used. Controlled clinical studies are lacking, however, on patients with hyposalivation due to Sjögren's syndrome, and only limited data are available from patients with radiation-induced hyposalivation. Obviously it is not possible to run placebo control groups; nevertheless, there have been no head-to-head comparisons of fluoride rinses, or of stannous fluoride, acidulated phosphate fluoride, or sodium fluoride gels, and thus no single protocol can be recommended. Accordingly, different centers have used these products interchangeably--for example, selecting a rinse regimen if patients complain of gagging when using a gel applied in a tray, or if the cost of the tray is prohibitive. Recent innovations that show promise for treatment of high-caries-risk patients with hyposalivation are the use of fluoride rinses in combination with chlorhexidine rinses or gels and the professional application of high-concentration chlorhexidine varnishes to the teeth.

Comparison between new saliva stimulants in patients with dry mouth: a placebo-controlled double-blind crossover study

Two new saliva stimulants: V6 and a mucin containing chewing gum were tested in this placebo-controlled double-blind crossover study. Forty-three patients (mean age 63 yr) complaining of dry mouth participated. The products were administered in a randomized order, and used for 2 wk each. The effect was evaluated by interviews and by determining changes in stimulated and unstimulated saliva flow rates. A positive effect was reported by 64%, 44%, and 26% of the patients using the mucin chewing gum, V6, and the placebo, respectively. More than 2/3 of the patients found the mucin chewing gum efficient at various times and situations. Sixty-one percent of the patients preferred the mucin chewing gum, 21% V6, and 5% the placebo product. Fifty percent of the patients had an increase in unstimulated salivary secretion rate from all products after 14 days regular use indicating a long-term effect.

Effects of chronic anethole trithione and amitriptyline treatment on rat parotid gland signalling

The present study examines the mechanism(s) of action of anethole trithione (Sulfarlem S25) compared to the sialogogue pilocarpine. The chronic effects (7 days of treatment) of anethole trithione, pilocarpine and/or amitriptyline on autonomic receptor binding (homogenates) were measured together with parallel tests of stimulation-induced rises in delta [Ca2+]i in collagenase-isolated rat parotid acini. The results revealed that chronic treatment with amitriptyline resulted in significantly increased rises in delta [Ca2+]i after stimulation with 20 microM of carbachol or adrenaline, and a significant increase in muscarinic acetylcholine receptor density. In addition, anethole trithione also increased cholinergic and adrenergic responsiveness. The double treatment of amitriptyline and anethole trithione or amitriptyline and pilocarpine did, however, prevent the rise in delta [Ca2+]i observed under conditions when these drugs were administered alone. Furthermore, anethole trithione, but not pilocarpine, was able to prevent the amitriptyline-induced upregulation in muscarinic acetylcholine receptor density. In conclusion, the experimental data presented in this study are compatible with the hypothesis that anethole trithione might stimulate some post-receptor effect in the coupling to the secretory response. In addition, this study supports the beneficial effects of anethole trithione in treating drug-induced xerostomia.

Oral health of patients with Alzheimer's disease

Generally healthy, unmedicated patients with Alzheimer's disease have few but significant changes in their oral health. Study results reinforce preventive oral hygiene for these patients.

Acute effects of a possible sialogogue, anethole trithione, in rat parotid glands

The present study examines the mechanism(s) of action of anethole trithione compared to the sialogogue pilocarpine. This was done by comparing the acute effects of these drugs on autonomic receptor binding (homogenates) together with parallel tests evaluating the biological activities of the receptor systems in collagenase-isolated rat parotid acini. The responses were measured as receptor-activated changes in cyclic nucleotide formation and acinar oxygen consumption. The results revealed that anethole trithione was unable to bind to muscarinic acetylcholine receptors and unable to stimulate the dynamic processes directly. It did, however, inhibit part (about 50%) of the carbachol-induced cyclic guanosine 3',5'-monophosphate (cyclic GMP) formation and O2 uptake. Furthermore, anethole trithione (greater than 1 microM) displaced [3H]prazosin (but not [3H]dihydroalprenolol ([3H]DHA] binding, without any effect upon the adrenaline-induced cyclic adenosine 3',5'-monophosphate (cyclic AMP) formation and O2 uptake. In conclusion, this study has shown that anethole trithione is not to be considered as a simple cholinergic agonist like pilocarpine, and further elucidation of the mechanism(s) of action of this agent would be useful.

In vitro methods for the assessment of the inhibitory effects of antidepressants in rat parotid glands

The present study evaluates suitable in vitro methods for the assessment of the inhibiting properties of four principally different antidepressant drugs. This was done by comparing the acute effects of antidepressants on autonomic receptor binding (homogenates) together with parallel tests evaluating the biological activities of the receptor systems in collagenase-isolated rat parotid acini. The responses were measured as receptor-activated changes in cyclic nucleotide formation and acinar oxygen consumption. Muscarinic acetylcholine receptor binding, carbachol-induced cGMP formation, and oxygen consumption all reflected the various inhibiting effects of the antidepressants tested. Measurements of the carbachol-induced O2 consumption was however, the most sensitive method and may be considered a well-suited and reliable parameter concerning the expected severity of anticholinergic side-effects caused by medication. The disturbing 'dry mouth' symptoms following treatment with amitriptyline or mianserin are however, also attributed to their substantial adrenoceptor-blocking effects, which are best demonstrated by alpha 1-adrenoceptor binding studies in combination with measurements of the adrenaline-induced O2 consumption in the rat parotid gland.

Dental needs related to primary cause for institutionalization

One hundred and forty-seven dentate residents of a long-term care facility were examined to determine oral status and need for treatment. The assessment included dental caries (NIDR criteria), oral hygiene index-simplified, and missing teeth. Caries was further divided into "restorable" and "nonrestorable." Also, the primary cause for institutionalization was determined.

How much saliva is enough? 'Normal' function defined

Saliva is important for the preservation and maintenance of oral health. It is unclear, however, how much saliva is required to maintain normal oral function. Major salivary gland flow rates, objective measurements of oral health, and subjective complaints of oral problems were assessed in different-aged, healthy persons. Results suggest that the comparison of major salivary gland flow rates of an individual with population standards to identify patients susceptible to the effects of salivary dysfunction is unreliable. Changes in salivary function over time are a more meaningful gauge of the impact of saliva on oral health. The clinician should monitor salivary production to identify patients with declining salivary gland output.