Long-term health-related quality of life in head and neck cancer survivors: A large multinational study

Head and neck cancer (HNC) patients suffer from a range of health-related quality of life (HRQoL) issues, but little is known about their long-term HRQoL. This study explored associations between treatment group and HRQoL at least 5 years' post-diagnosis in HNC survivors. In an international cross-sectional study, HNC survivors completed the European Organization for Research and Treatment of Cancer (EORTC) quality of life core questionnaire (EORTC-QLQ-C30) and its HNC module (EORTC-QLQ-H&N35). Meaningful HRQoL differences were examined between five treatment groups: (a) surgery, (b) radiotherapy, (c) chemo-radiotherapy, (d) radiotherapy ± chemotherapy and neck dissection and (e) any other surgery (meaning any tumour surgery that is not a neck dissection) and radiotherapy ± chemotherapy. Twenty-six sites in 11 countries enrolled 1105 survivors. They had a median time since diagnosis of 8 years, a mean age of 66 years and 71% were male. After adjusting for age, sex, tumour site and UICC stage, there was evidence for meaningful differences (10 points or more) in HRQoL between treatment groups in seven domains (Fatigue, Mouth Pain, Swallowing, Senses, Opening Mouth, Dry Mouth and Sticky Saliva). Survivors who had single-modality treatment had better or equal HRQoL in every domain compared to survivors with multimodal treatment, with the largest differences for Dry Mouth and Sticky Saliva. For Global Quality of Life, Physical and Social Functioning, Constipation, Dyspnoea and Financial Difficulties, at least some treatment groups had better outcomes compared to a general population. Our data suggest that multimodal treatment is associated with worse HRQoL in the long-term compared to single modality.

Associations between patient-reported late effects and systemic cytokines in long-term survivors of head and neck cancer treated with radiotherapy

PURPOSE

Head and neck cancer (HNC) treatment may lead to late effects and impaired health-related quality of life of survivors. Knowledge on long-term late effects after radiotherapy (RT) and potential underlying biological mechanisms is lacking. We assessed the prevalence of xerostomia, dysphagia, and chronic fatigue (CF) in HNC survivors ≥ 5 years post-RT, and examined associations between pro-inflammatory cytokines and late effects.

METHODS

In a cross-sectional study, 263 HNC survivors treated between 2007 and 2013 were enrolled. They completed validated questionnaires assessing xerostomia and dysphagia (the EORTC QLQ-H&N35), and CF (the Fatigue Questionnaire), and underwent blood sampling and clinical examination. Pro-inflammatory cytokines were analyzed in 262 survivors and 100 healthy age- and gender-matched controls.

RESULTS

Median time since treatment was 8.5 years. The proportions of survivors reporting xerostomia, dysphagia, and CF were 58%, 31%, and 33%, respectively, with a preponderance of females. We found no significant associations between IL-6, IL-8, IP-10, TARC, TNF, or ENA-78 and the three late effects. The odds of having elevated levels of IL-6 and IP-10 were significantly higher in the survivors compared to the controls.

CONCLUSIONS

More than one-third of long-term HNC survivors experienced xerostomia, dysphagia, and CF. Persistent inflammation, with elevated systemic cytokines, was not associated with these late effects, although HNC survivors had higher levels of some cytokines than the controls.

IMPLICATIONS FOR CANCER SURVIVORS

This study provides new knowledge on late effects that can serve as grounds for informing patients with HNC about risk of late effects more than 5 years after RT.

Serious Long-Term Effects of Head and Neck Cancer from the Survivors' Point of View

The long-term problems of head and neck cancer survivors (HNCS) are not well known. In a cross-sectional international study aimed at exploring the long-term quality of life in this population, 1114 HNCS were asked to state their two most serious long-term effects. A clinician recorded the responses during face-to-face appointments. A list of 15 example problems was provided, but a free text field was also available. A total of 1033 survivors responded to the question. The most frequent problems were 'dry mouth' (DM) (n = 476; 46%), 'difficulty swallowing/eating' (DSE) (n = 408; 40%), 'hoarseness/difficulty speaking' (HDS) (n = 169; 16%), and 'pain in the head and neck' (PHN) (n = 142; 14%). A total of 5% reported no problems. Logistic regression adjusted for age, gender, treatment, and tumor stage and site showed increased odds of reporting DM and DSE for chemo-radiotherapy (CRT) alone compared to surgery alone (odds ratio (OR): 4.7, 95% confidence interval (CI): 2.5-9.0; OR: 2.1, CI: 1.1-3.9), but decreased odds for HDS and PHN (OR: 0.3, CI: 0.1-0.6; OR: 0.2, CI: 0.1-0.5). Survivors with UICC stage IV at diagnosis compared to stage I had increased odds of reporting HDS (OR: 1.9, CI: 1.2-3.0). Laryngeal cancer survivors had reduced odds compared to oropharynx cancer survivors of reporting DM (OR: 0.4, CI: 0.3-0.6) but increased odds of HDS (OR: 7.2, CI: 4.3-12.3). This study provides evidence of the serious long-term problems among HNCS.

Targeting a therapeutically relevant concentration of alendronate for in vitro studies on osteoblasts

OBJECTIVE

Bisphosphonates like alendronate mainly exert their effects on osteoclasts. However, osteoblasts are also affected, but exposed to a much lower concentration in vivo than the osteoclasts. Given that the effects are dose-dependent, the intention of the study was to identify a therapeutically relevant concentration of alendronate for in vitro studies on osteoblasts.

MATERIALS AND METHODS

Primary human osteoblasts were incubated with alendronate (5, 20 and 100 µM) for 1, 3, 7 and 14 days. Proliferation and viability were assessed, and the effects on cellular growth and function were evaluated by multianalyte profiling of selected proteins in cell culture media using the Luminex 200^TM.

RESULTS

The viability was not affected by any of the dosages. Exposure to 5 µM alendronate had a neutral effect on osteoblast proliferation, and on secretion of osteogenic and inflammatory markers, while enhancing synthesis of a marker of angiogenesis. 20 µM alendronate induced a decline in proliferation and affected angiogenic and osteogenic biomarkers adversely. 100 µM alendronate reduced proliferation dramatically, and this dosage was excluded from further experiments.

CONCLUSION

A concentration of 5 µM alendronate exerted effects on human osteoblasts that may translate to those observed in vivo and could therefore be relevant for in vitro studies.

Alendronate and omeprazole in combination reduce angiogenic and growth signals from osteoblasts

Objective

Due to gastrointestinal side effects of oral bisphosphonates (BPs), proton pump inhibitors (PPIs) are often prescribed. PPIs may enhance the risk of osteonecrosis of the jaw, a rare side effect of BPs. Therefore, the objective of this study was to evaluate the effects of the oral BP alendronate (ALN) and the PPI omeprazole (OME) alone and in combination on primary human osteoblasts and gingival fibroblasts in vitro.

Methods

Human gingival fibroblasts and normal human osteoblasts were incubated with either 5 μM of ALN or 1 μM of OME, or ALN + OME for 1, 3, 7 or 14 days. Effect on viability was evaluated by the lactate dehydrogenase activity in the medium and on proliferation by quantifying 3H-thymidin incorporation. Multianalyte profiling of proteins in cell culture media was performed using the Luminex 200TM system to assess the effect on selected bone markers and cytokines.

Results

The proliferation of osteoblasts and fibroblasts was reduced upon exposure to ALN + OME. ALN induced an early, temporary rise in markers of inflammation, and OME and ALN + OME promoted a transient decline. An initial increase in IL-13 occurred after exposure to all three options, whereas ALN + OME promoted IL-8 release after 7 days. OME and ALN + OME promoted a transient reduction in vascular endothelial growth factor (VEGF) from osteoblasts, whereas ALN and ALN + OME induced a late rise in VEGF from fibroblasts. Osteoprotegerin release was enhanced by ALN and suppressed by OME and ALN + OME.

Conclusions

ALN + OME seemed to exaggerate the negative effects of each drug alone on human osteoblasts and gingival fibroblasts. The anti-proliferative effects, modulation of inflammation and impairment of angiogenesis, may induce unfavorable conditions in periodontal tissue facilitating development of osteonecrosis.

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Alendronate and omeprazole reduce proliferation in osteoblasts and fibroblasts.

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Unchanged viability after exposure to either drug or the combination

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Omeprazole, alone and combined with alendronate, cause impairment of angiogenesis.

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Alendronate promotes an initial, transient increase in pro-inflammatory cytokines.

Oral disorders, saliva secretion, and oral health-related quality of life in patients with primary Sjögren's syndrome

Chemosensory function, burning sensations in the tongue (BST), halitosis, saliva secretion, and oral health-related quality of life (OHRQoL) were investigated in patients with primary Sjögren's syndrome (pSS). In 31 patients with pSS and 33 controls, olfactory and gustatory functions were evaluated. Self-reported complaints of dysgeusia, BST, and halitosis were recorded. Saliva secretion rates were measured and OHRQoL was assessed using the short-form Oral Health Impact Profile (OHIP-14). Patients had significantly lower olfactory (8.8 ± 3.5 vs. 10.7 ± 1.2) and gustatory (18.9 ± 7.1 vs. 25.4 ± 4.3) scores than controls, and significantly more patients complained of dysgeusia (58.1% vs. 0%), BST (54.8% vs. 6.1%), and halitosis (41.9% vs. 0%). A significantly greater proportion of patients with pSS had ageusia (19% vs. 0%), hypogeusia (32% vs. 12%), anosmia (13% vs. 0%), or hyposmia (29% vs. 9%). Significantly lower saliva secretion rates (ml min^-1 ) were observed in patients with pSS for stimulated (0.62 ± 0.40 vs. 1.57 ± 0.71) and unstimulated (0.08 ± 0.07 vs. 0.29 ± 0.17) saliva. The mean OHIP-14 score was significantly higher in patients with pSS (16.2 ± 10.8 vs. 2.7 ± 3.1) and was positively correlated with dysgeusia, BST, and halitosis. In conclusion, patients with pSS reported higher occurrence of dysgeusia, BST, and halitosis, and demonstrated relatively impaired chemosensory and salivary functions. The patients' poorer OHRQoL was associated with dysgeusia, BST, and halitosis.

Alendronate alters osteoblast activities

OBJECTIVE

Due to accumulation in the bone matrix and a half-life of at least 10 years, it is important to understand the cellular impact of bisphosphonates (BPs). This study assessed the effects of alendronate (ALN) on human primary osteoblasts.

MATERIAL AND METHODS

Osteoblasts were incubated with ALN (5, 20 and 100 μM), and both cells and cell culture media were harvested after d 1, 3, 7 or 14. Proliferation was evaluated by ³H-thymidine incorporation and tetrazolium dye (MTT) colorimetric assay, and viability by the lactate dehydrogenase (LDH) activity in the medium. Differentiation was evaluated using protein Luminex multiplex assays and RT-PCR.

RESULTS

ALN had no significant effects on cell viability. The lower concentrations enhanced the proliferation, whereas 100 μM diminished the proliferation. mRNA expression of osteocalcin (OC), alkaline phosphatase (ALP) and α-1 type 1 collagen were reduced, whereas ALN enhanced the expression of leptin mRNA and the secretion of interleukin-8 (IL-8) and regulated on activation normal T cell expressed and secreted (RANTES).

CONCLUSIONS

ALN enhanced the secretion of immune factors from human osteoblasts. Combined with a lower rate of proliferation and a decline in differentiation, this indicates that higher dosages or accumulation may cause undesirable local changes in bone.

International field testing of the psychometric properties of an EORTC quality of life module for oral health: the EORTC QLQ-OH15

PURPOSE

This international EORTC validation study (phase IV) is aimed at testing the psychometric properties of a quality of life (QoL) module related to oral health problems in cancer patients.

METHODS

The phase III module comprised 17 items with four hypothesized multi-item scales and three single items. In phase IV, patients with mixed cancers, in different treatment phases from 10 countries completed the EORTC QLQ-C30, the QLQ-OH module, and a debriefing interview. The hypothesized structure was tested using combinations of classical test theory and item response theory, following EORTC guidelines. Test-retest assessments and responsiveness to change analysis (RCA) were performed after 2 weeks.

RESULTS

Five hundred seventy-two patients (median age 60.3, 54 % females) were analyzed. Completion took <10 min for 84 %, 40 % expressed satisfaction that these issues were addressed. Analyses suggested a revision of the phase III hypothesized scale structure. Two items were deleted based on a high degree of item misfit, together with negative patient feedback. The remaining 15 items formed one eight-item scale named OH-QoL score, a two-item information scale, a two-item scale regarding dentures, and three single items (sticky saliva/mouth soreness/sensitivity to food/drink). Face and convergent validity and internal consistency were confirmed. Test-retest reliability (n = 60) was demonstrated as was RCA for patients undergoing chemotherapy (n = 117; p = 0.06). The resulting QLQ-OH15 discriminated between clinically distinct patient groups, e.g., low performance status vs. higher (p < 000.1), and head-and-neck cancer versus other cancers (p < 0.03).

CONCLUSION

The EORTC module QLQ-OH15 is a short, well-accepted assessment tool focusing on oral problems and QoL to improve clinical management.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01724333.

Norwegian LongoVital and recurrent aphthous ulceration: a randomized, double-blind, placebo-controlled study

OBJECTIVE

LongoVital (LV) is a herbal-based tablet enriched with the recommended daily doses of vitamins. The present study was undertaken to investigate possible prevention of recurrent aphthous ulceration (RAU) during 4 months daily intake of the Norwegian LV.

DESIGN

The study was a placebo-controlled, double-blind, randomized, clinical trial.

SUBJECTS

Sixty otherwise healthy patients with at least one attack of minor RAU per 2 months were included in the study.

METHODS

After an introduction period (IP) of 60 days, the patients were randomly divided into three groups and given either LV, the herbs of LV only, or placebo. Three test tablets were taken every day together with breakfast for 4 months [tablet period (TP)] and the patients followed up for another 4 months (F-UP). The number of new ulcers (NU) and ulcer-free days (UFD) were observed.

RESULTS

Fifty-two patients completed the study. Neither NU nor UFD showed any statistical significant differences between any of the groups in any of the periods. All three groups, however, showed a significant increase in UFD during the first 2 months of TP compared to IP. Within the LV group only, there was a further increase in UFD after 2 months intake of the tablets. The number of NU and UFD decreased significantly in both the LV and the herbal group in F-UP compared with TP.

CONCLUSION

Neither the Norwegian LV nor the herbal component alone was superior to placebo in the prevention of RAU. The results, however, indicate that neither the LV nor the herbal group benefited from the treatment.

Oral mucosal side effects of cytotoxic chemotherapy of testicular cancer. A retrospective study

Cancer chemotherapy often leads to injury of normal cells. Adverse effects on oral mucosa have been documented for several cytotoxic treatment regimens. The aim of the present retrospective study was to evaluate incidence and degree of oral soft tissue side-effects of a cisplatin-based chemotherapy regimen used for treating testicular cancer. The study was based upon a questionnaire mailed to 56 consecutive patients treated at the Norwegian Radium Hospital. A total of 39 individuals joined the study, as 2 patients refused and 15 did not reply. The patients were divided into two groups, a case group (24 individuals) having received 4 7 cycles of cisplatin-based chemotherapy in addition to surgery, and a control group (15 individuals) treated with surgery alone. The study revealed that 62% of the patients in the chemotherapy group developed adverse soft tissue reactions, with mucositis and pain as chief complaints, whereas none in the control group experienced any mucosal complications.

Increased human gingival blood flow induced by sodium lauryl sulfate

Laser Doppler flowmetry was used in 14 subjects to investigate the effect of sodium lauryl sulfate (SLS) on gingival microcirculation. SLS, the most widely used detergent in toothpastes, exhibits a denaturing property, increases oral mucosal permeability and may cause epithelial desquamation of oral soft tissues. Gingival blood flow (GBF) was measured bilaterally 3 mm above the gingival margin, between the central and lateral maxillary incisors, before and after application of 1.5% SLS for 90 s to the gingiva on one side. The contralateral side served as a control with water application only. Relative changes in GBF were measured for 15 min on both sides. SLS increased the median GBF significantly between the 2nd and 10th min with a peak at 8 min, whereafter the flow decreased towards baseline. On the contralateral side, GBF initially declined before returning to baseline. 10 subjects felt a burning pain from the gingiva after SLS application and GBF increased in all of them. SLS increased the relative gingival blood flow presumably due to its penetrating and irritative properties, which resulted in vasodilatation. Laser Doppler flowmetry may be a useful non-invasive method for intraoral testing of different agents meant for oral use.

The effects of sodium lauryl sulfate on the phrenic nerve diaphragm preparation from the rat

The time period to 50% inhibition of the twitches and compound action potential of the rat phrenic nerve-diaphragm preparation with sodium lauryl sulfate (2.5 x 10(-4)-5.0 x 10(-3)M) was recorded. The twitch contractions during indirect stimulation, the contraction during direct stimulation, and the compound action potential of the isolated phrenic nerve, were inhibited in that order. Depolarization due to high action potential activity induced by tetanic stimulation, veratridine, low Ca(2+)-or high K(+)-solutions, all enhanced the inhibitory effect of sodium lauryl sulfate (5.0 x 10(-4)M) during indirect stimulation. Hyperpolarization in K(+)-free solution and membrane stabilization by lidocaine antagonized the inhibitory effect of sodium lauryl sulfate. Accordingly, it probably induced inhibition by depolarization. The depolarization may decrease the influx of Ca2+ and the reuptake of choline+, as suggested by an observed synergism with tetraethylammonium CI and hemicholinium-3 Br, which antagonize the reuptake of choline+. On the opposite, 3,4-diaminopyridine, which increases the influx of Ca2+, antagonized the sodium lauryl sulfate-induced inhibition, and induced a biphasic contracture. The first phase was probably caused by a depolarization, and the second phase by release of Ca2+ from the sarcoplasmic reticulum. The potentiation of the second phase by dantrolene and in low Ca2+ solution, was attributed to sodium lauryl sulfate-induced desensitization.

Mouthrinses containing triclosan reduce the incidence of recurrent aphthous ulcers (RAU)

Triclosan, an antibacterial agent introduced in toothpastes and mouthrinses, has recently been shown to have anti-inflammatory and analgesic properties. The aim of the present double-blind cross-over study was to examine the effect of triclosan on the incidence of recurrent aphthous ulceration (RAU) when administered in mouthrinses. The study included 30 patients with a history of multiple recurrent aphthous ulcers. Three different triclosan-containing mouthrinses, differing only in their solubilizing agents were used and compared with a control rinse. The number of new ulcers, ulcer-free days and the severity of pain were recorded. The results showed that the patients experienced a significant decrease in the number of oral ulcers during the experimental period when the mouthrinses contained triclosan. It may thus be concluded that triclosan has the potential to reduce the number of aphthous ulcers presumably due to its anti-inflammatory properties.

The effect of two toothpaste detergents on the frequency of recurrent aphthous ulcers

The aim of the present clinical double-blind crossover study was to investigate the effect of two different toothpaste detergents, sodium lauryl sulfate (SLS) and cocoamidopropyl betaine (CAPB), as compared with a detergent-free paste, on 30 patients with frequent occurrences of recurrent aphthous ulcers. The study consisted of three 6-week periods during which the patients brushed twice daily with the different test toothpastes. The localization and number of new ulcers were assessed. A significantly higher frequency of aphthous ulcers was demonstrated when the patients brushed with an SLS- than with a CAPB-containing or a detergent-free placebo paste. An SLS-free toothpaste may thus be recommended for patients with recurrent aphthous ulcers.

Oral mucosal desquamation of pre- and post-menopausal women. A comparison of response to sodium lauryl sulphate in toothpastes

The aim of the present study was to investigate whether a difference in susceptibility to chemically induced irritation of the oral mucosa in 14 pre- and 14 post-menopausal women exists, following local exposure to sodium lauryl sulphate (SLS) in toothpastes. 4 different pastes differing only in detergent concentration present, or not, were used. The participants applied 1 cm of the different test toothpastes to a cap splint covering the teeth and the oral mucosa of the upper jaw 2 x daily for 2 min during a period of 4 days. 42 desquamative reactions of the oral mucosa (in 20 subjects) were observed, 29 and 13 in the pre- and the post-menopausal group, respectively. Desquamation was only experienced following exposure to SLS-containing toothpastes, not succeeding SLS-free paste. The results demonstrated that oral mucosa of pre-menopausal women was significantly more sensitive to SLS than oral mucosa of post-menopausal women. The difference in mucosal irritation between the 2 groups increased with increasing concentration of SLS.

Oral mucosal desquamation caused by two toothpaste detergents in an experimental model

Sodium lauryl sulfate (SLS), the most widely used detergent in toothpastes, has been reported to cause adverse effects on oral soft tissues. This double-blind cross-over study describes the oral mucosal effects of SLS-containing toothpastes and pastes containing a zwitterionic detergent, cocoamidopropyl-betaine (CAPB) in an experimental model in 28 healthy females. Seven toothpastes, differing only in detergent concentration and/or type, were used: SLS (0.5, 1.0, 1.5%), CAPB (0.64, 1.27, 1.90%) and a placebo. Each participant applied 1 cm of assigned test toothpaste via a cap splint to the teeth and the mucosa of the upper jaw. The splints were used twice daily for 2 min during a period of 4 d, after which the participants were examined for oral desquamation. No other oral hygiene was allowed during the test periods. Ten days brushing with a detergent-free toothpaste was performed between each test period. Forty-five desquamative reactions were observed in 21 of 27 subjects (one was excluded) during the trial. Forty-two reactions were recorded during the SLS periods and the remaining three during the CAPB periods. The detergent-free toothpaste did not result in oral desquamation. SLS in toothpastes significantly increased the incidence of desquamation of the oral mucosa compared with toothpastes containing the detergent CAPB. The model used is not directly relevant to normal toothbrushing with toothpaste, but indicates that sensitive patients may contract mucosal irritation through SLS in toothpastes. Less toxic detergents, e.g. CAPB, are desirable in oral hygiene products.

Inhibitory effects of HgCl2 on excitation-secretion coupling at the motor nerve terminal and excitation-contraction coupling in the muscle cell

1. Indirect and direct twitch (0.1-Hz) stimulation of the rat phrenic nerve-diaphragm disclosed that the inhibitory effect of HgCl2, 3.7 x 10(-5) M, on the neuromuscular transmission and in the muscle cell, was accelerated by 10-sec periods of 50-Hz tetanic stimulation every 10 min. This activity-dependent enhancement suggested an inhibitory mechanism of HgCl2 related to the development of fatigue, like membrane depolarization or decreased excitability, decreased availability of transmitter, or interference with the factors controlling excitation-secretion coupling of the nerve terminal, i.e. (Ca2+)0 or (Ca2+)i, and excitation-contraction coupling in the muscle cell, i.e., (Ca2+)i. 2. During both indirect and direct stimulation, HgCl2-induced inhibition was enhanced markedly by pretreatment with caffeine, which releases Ca2+ from endoplasmic and sarcoplasmic reticulum in the nerve terminal and muscle cell, respectively. This caffeine-induced enhancement was completely antagonized by dantrolene, which inhibits the caffeine-induced release. However, dantrolene alone did not antagonize the HgCl2-induced inhibition. 3. Since caffeine depletes the intracellular Ca2+ stores of the smooth endoplasmic reticulum, HgCl2 probably inhibits by binding to SH groups of transport proteins conveying the messenger function of (Ca2+)i. In the muscle cell this leads to inhibition of contraction. In the nerve terminal, an additional enhancement of the HgCl2-induced inhibition, by inhibiting reuptake of choline by TEA and tetanic stimulation, suggested that HgCl2 inhibited a (Ca2+)i signal necessary for this limiting factor in resynthesis of acetylcholine. 4. The (Ca2+)0 signal necessary for stimulus-induced release of acetylcholine was not affected by HgCl2. Hyperpolarization in K(+)-free solution antagonized the inhibitory effect of HgCl2 at indirect stimulation, and Ca(2+)-free solution enhanced the inhibitory effect at direct stimulation. K+ depolarization, membrane electric field increase with high Ca2+, membrane stabilization with lidocaine, and half-threshold stimulation, did not change the inhibitory effect of HgCl CH3HgCl. 1.85 x 10(-5) M, disclosed a synergistic interaction with caffeine during direct, but not during indirect, stimulation.

Sodium lauryl sulfate and recurrent aphthous ulcers. A preliminary study

Sodium lauryl sulfate (SLS), a synthetic detergent commonly used in dentifrices, is an effective denaturant. The aim of the present study was to investigate the effect of SLS in patients with recurrent aphthous ulcers (RAU). Ten patients with multiple minor RAU participated in the study. The mean incidence of RAU was 17.8 during a 3-month period before the study. The patients used a dentifrice containing 1.2% SLS for a test period of 3 months followed by a dentifrice without SLS for the same time period. The results showed a statistically significant decrease in the number of aphthous ulcers from 14.3 after using the SLS-containing dentifrice to 5.1 ulcers after brushing with the SLS-free dentifrice (p < 0.05). It is suggested that the denaturing effect of SLS on the oral mucin layer, with exposure of the underlying epithelium, induces an increased incidence of RAU.

Desquamative effect of sodium lauryl sulfate on oral mucosa. A preliminary study

Sodium lauryl sulfate (SLS) is the most commonly used detergent in dentifrices. The present study was concerned with the effect of SLS content of toothpastes on oral epithelial desquamation in an experimental model. Ten dental hygiene students participated in this double-blind cross-over study. Five dentifrices with different concentrations of SLS (ranging from 0.0% to 1.5%) were used in randomized order in the study. One centimeter of each test dentifrice was applied in a cap-splint, which covered both attached and non-attached oral mucosa of the upper jaw for 2 min twice daily. The test period for each experimental dentifrice was 4 days, followed by a 10-day rest period. The dentifrice without SLS did not result in any onward reaction, whereas the dentifrice containing 1.5% SLS provoked desquamation in 60% of the subjects.