Chewing

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Chewing

  • betel chewing
  • betel quid chewing
  • gum chewing
  • nut chewing
  • quid chewing
  • unilateral chewing

  • Terms modified by Chewing

  • chewing ability
  • chewing cycle
  • chewing efficiency
  • chewing gum
  • chewing habit
  • chewing louse
  • chewing movement
  • chewing pattern
  • chewing side
  • chewing stick
  • chewing stroke
  • chewing task
  • chewing time

  • Selected Abstracts


    A DELIRIOUS PATIENT WITH OPIOID INTOXICATION AFTER CHEWING A FENTANYL PATCH

    JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 8 2006
    Rein Van Rijswijk MD
    No abstract is available for this article. [source]


    Factors influencing proximal dental contact strengths

    EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 5 2000
    Christof E. Dörfer
    The aim of this study was to systematically measure proximal contact strength in complete natural dentitions of 30 adults (25.3±3.0 years of age), and to analyze its relationship to tooth type, tooth location, chewing effort and time of day variation. The contact strengths were measured dynamically during removal of a calibrated 0.05-mm-thick metal strip between the proximal contacts of adjacent teeth. Proximal contact strengths were lower in the maxilla (2.51±1.36 N) compared to the mandible (4.26±1.88 N). Within the jaws, the lowest proximal contact strength was measured between canine and first premolar (2.91±1.79 N) and the highest between second premolar and first molar (3.73±1.95 N). Chewing increased the proximal contact strength within the maxilla (before: 2.51±1.36 N, after: 3.02±1.45 N) but it remained unchanged in the mandible (before: 4.26±1.88 N, after: 4.22±1.85 N). The proximal contact strength increased significantly from morning (3.39±1.86 N) to noon (3.61±1.77 N), and then decreased in the afternoon (3.43±1.60 N). It was concluded that proximal contact strength can be significantly influenced by location, tooth type, chewing and time of day variation. Based on the differences in distribution due to the effect of chewing and time of day, it is speculated that proximal contact strength is a physiological entity of multifactorial origin. [source]


    Length of the occlusal glide during chewing in children with primary dentition

    JOURNAL OF ORAL REHABILITATION, Issue 11 2003
    H. Hayasaki
    summary, Chewing is one of the most important functions of the mandible, but, to date, there are very few studies of this function in children. The purpose of this study was to quantify the length of the occlusal glide at the lower incisal point during gum chewing in children with primary dentition. Eleven girls with primary dentition were selected for this study. Mandibular excursions with occlusal contacts and gum chewing movement were measured using an optoelectronic system that can measure mandibular movement with six degrees-of-freedom at a sampling frequency of 100 Hz. A curved mesh diagram of incisor coordinates during mandibular excursions was established to calculate the length of the occlusal glide for each subject. The occlusal glide lengths of children were compared with previously reported results for adults. The estimated length of the occlusal glide during closing was significantly shorter in children than in adults, contrary to that during opening. This result suggests that children have a characteristic chewing pattern that differs from adults. [source]


    Dental Status and Quality of Life in Long-Term Head and Neck Cancer Survivors,

    THE LARYNGOSCOPE, Issue 4 2005
    Rebecca L. Duke MD
    Abstract Objectives: To analyze how the dental status of long-term head and neck cancer survivors affects their subjective quality of life. Study Design: Observational case series. Methods: A convenience sample of 5-year head and neck cancer survivors underwent the following battery of tests: 1) targeted head and neck examination, 2) updated medical history, 3) dental evaluation, 4) standardized quality of life questionnaires. Results: Eighty-six survivors were included in the study. The following associations were identified: 1) those who became edentulous secondary to cancer treatment and those without occlusion at time of the study demonstrated worse Pain, Activity, Recreation/Entertainment, Chewing, Swallowing, Speech, Eating in Public, Normalcy of Diet, Physical Well-Being, Social/Family Well-Being, Functional Well-Being, and Additional Concerns scores; 2) higher Decayed/Missing/Filled scores were associated with worse Pain, Disfigurement, Activity, Recreation/Entertainment, Employment, Chewing, Swallowing, Speech, Eating in Public, Understandability of Speech, Normalcy of Diet, Physical Well-Being, Additional Concerns scores, and weight loss; 3) decreased oral opening measurements were associated with worse Chewing, Swallowing, Eating in Public, Normalcy of Diet, Additional Concerns scores, and weight loss; 4) edentulous survivors who did not use dentures had worse Pain, Activity, Recreation/Entertainment, Understandability of Speech, and Eating in Public sco es. Conclusions: Although previous studies have shown that many of the effects of cancer treatment disappear between 1 and 3 years, this study shows that the dental status has a persistent impact on subjective quality of life. [source]


    The oral health consequences of chewing areca nut

    ADDICTION BIOLOGY, Issue 1 2002
    C. R. Trivedy
    Its effects on dental caries and periodontal tissues, two major oral diseases, are less well researched. Areca-induced lichenoid lesions mainly on buccal mucosa or tongue are reported at quid retained sites. In chronic chewers a condition known as betel chewer's mucosa, a discoloured areca nut-encrusted change, is often found where the quid particles are retained. Areca nut chewing is implicated in oral leukoplakia and submucous fibrosis, both of which are potentially malignant in the oral cavity. Oral cancer often arises from such precancerous changes in Asian populations. In 1985 the International Agency for Research on Cancer concluded that there is limited evidence to conclude that areca chewing may directly lead to oral cancer. There is, however, new information linking oral cancer to pan chewing without tobacco, suggesting a strong cancer risk associated with this habit. Public health measures to quit areca use are recommended to control disabling conditions such as submucous fibrosis and oral cancer among Asian populations. [source]


    Areca nut use following migration and its consequences

    ADDICTION BIOLOGY, Issue 1 2002
    S. Warnakulasuriya
    The combined use of areca nut and smokeless tobacco (ST) is practiced particularly in the Indo-Chinese continents. While there is considerable global variation in the use of these products, migrant studies relevant to areca nut use is of considerable interest to epidemiologists in suggesting the extent to which these environment exposures are important in the aetiology of different cancers and other health-related consequences. Studies on Indian migrants to the Malay peninsula, South and east Africa and various Asian ethnic groups resident in several parts of the United Kingdom have shown that the consumption of areca nut (often mixed with ST) is highly prevalent in these communities. Available data on the prevalence of areca chewing among these migrant populations are reviewed here. The carriage of these risk factors from South Asia to other countries has resulted in excess risk of oral cancer in these new settlements. There is also a high incidence of cardiovascular disease, hypertension and late onset diabetes among Indians living in the United Kingdom and there is new evidence to suggest that the combined roles of areca and ST may be contributory. Because of their enhanced financial situation, substance abuse may increase in their new country of domicile. The two products are psychologically addictive and a dependency syndrome related to their use among Asian immigrants to the United Kingdom has been described recently. [source]


    Living with a child with a severe orofacial handicap: experiences from the perspectives of parents

    EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 1 2003
    Ulrika Trulsson
    Orofacial functions include competences/abilities such as eating, breathing, speech/language, mimicry, as well as oral health, and disturbances are common in children with rare disorders. To describe parental experiences of orofacial function and needs in children with rare disorders, in-depth interviews focusing on orofacial function were carried out with 14 parents. Interviews were transcribed verbatim and analysed in open, axial (theoretical) and selective coding processes according to Grounded Theory. Two core categories emerged from data in the analysis: ,the vulnerable family' and ,support perceived from others'. The data indicated the importance of a balance between these two core categories: the strain caused by living in a family with a child with a severe disability/handicap, and the availability of perceived support from caregivers and significant others. This balance was necessary for the parents in developing self-reliance and in reconciling themselves to their life situations. Parents described orofacial dysfunction in terms of feeding and communication problems, needs for orthodontic treatment to reduce risk of trauma or improve chewing, and drooling. Oral health issues such as dental caries and gingivitis were not mentioned. Five aspects of good professional attitude were recognized: respect, involvement, continuity, knowledge, and availability. [source]


    Antero-posterior activity changes in the superficial masseter muscle after exposure to experimental pain

    EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 2 2002
    Jens C. Türp
    The aim of this randomized, controlled, double-blind study was to examine how the activation pattern of the masseter muscle changes during natural function when experimental pain is induced in a discrete anterior area of the muscle. In 20 subjects, three bipolar surface electrodes and three intramuscular fine-wire electrodes (antero-posterior mapping) were simultaneously attached above and in the right masseter muscle to record the electromyographic (EMG) activity during unilateral chewing before and after infusion of a 0.9% isotonic and 5% hypertonic saline bolus in the anterior area of the muscle. The activity of the contralateral masseter muscle was registered by surface electrodes. In addition, the development of pain intensity was quantitatively measured with a numerical rating scale (NRS). While both saline concentrations caused pain, the hypertonic solution evoked stronger pain. The experiments also provided evidence of a significant although differential activity reduction of the ipsilateral masseter muscle in the antero-posterior direction. The activity reduction decreased with increasing distance from the location of the infusion. The results support the idea that the strategy of differential activation protects the injured muscle while simultaneously maintaining optimal function. [source]


    Effects of prolonged gum chewing on pain and fatigue in human jaw muscles

    EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 2 2001
    Mauro Farella
    Gum chewing has been accepted as an adjunct to oral hygiene, as salivary stimulant and vehicle for various agents, as well as for jaw muscle training. The aim of this study was to investigate the effects of prolonged gum chewing on pain, fatigue and pressure tenderness of the masticatory muscles. Fifteen women without temporomandibular disorders (TMD) were requested to perform one of the following chewing tasks in three separate sessions: chewing a very hard gum, chewing a soft gum, and empty-chewing with no bolus. Unilateral chewing of gum or empty chewing was performed for 40 min at a constant rate of 80 cycles/min. In each session, perceived muscle pain and masticatory fatigue were rated on visual analog scales (VAS) before, throughout, and after the chewing task. Pressure pain thresholds (PPTs) of masseter and anterior temporalis muscles were assessed before and immediately after the chewing tasks, and again after 24 h. The VAS scores for pain and fatigue significantly increased only during the hard gum chewing, and after 10 min of recovery VAS scores had decreased again, almost to their baseline values. No significant changes were found for PPTs either after hard or soft gum chewing. The findings indicate that the jaw muscles recover quickly from prolonged chewing activity in subjects without TMD. [source]


    Longitudinal health-related quality of life after mandibular resection for oral cancer: a comparison between rim and segment,

    HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 1 2004
    Simon N. Rogers FDS
    Abstract Background. Mandibular resection for oral cancer is often necessary to achieve an adequate margin of tumor clearance. Segmental mandibulectomy has been associated with a poor health-related quality of life (HRQOL), particularly before composite free tissue transfer to reconstruct the defect. Little is published in the literature contrasting the subjective deficit of segmental compared with rim resection. The aim of this study was to use a validated head and neck HRQOL questionnaire to compare rim and segmental mandibular resection in patients having primary surgery for oral cancer. Method. There were 224 consecutive patients between 1995 and 1999 who were treated by primary surgery for oral squamous cell carcinoma. One hundred twenty-tree had no mandibular resection, 44 had a rim resection, and 57 had a segmental resection. The University of Washington Quality of life questionnaire (UW-QOL) was adminstered before treatment, at 6 months, 12 months and after 18 months. Results. Preoperatively, patients undergoing segmental resection reported significantly more pain, chewing problems, and a lower composite UW-QOL score. Postperatively, the segment group tended to score worse at all time points, particularly in appearance, swallowing, recreation, and chewing; however, the difference between rim and segment was only seen in smaller resections without adjuvant radiotherapy. Little difference was seen between rim or segment for tumors <4 cm with radiotherapy and between rim and segments for tumors >4cm. Conclusion: After segmental mandibulectomy and reconstruction using composite free tissue transfer, the UW-QOL scores were relatively good. The only 2 difference between rim and segments was noted in the small resections without radiotherapy, and some of this was reflected in differences at baseline. © 2004 Wiley Periodicals, Inc. Head Neck26: 54,62, 2004. [source]


    Standardized health check data from community-dwelling elderly people: the potential for comparing populations and estimating need

    HEALTH & SOCIAL CARE IN THE COMMUNITY, Issue 1 2000
    Peter Bath PhD
    Abstract The main aim of this study was to compare EASY-Care data obtained during nurse-administered annual health checks in two populations of older people. A secondary aim was to determine whether a standardized assessment system administered as part of routine practice by a trained nurse during the over-75 health check could generate useful information for comparing population health and functional status of community-dwelling-older people. One hundred and seventy-nine elderly people (aged 75 years and over) from the Woodstock ward, Belfast, having relatively high deprivation; and 238 elderly people from south Hampshire, ranging from affluent wards in New Forest to inner city wards, were assessed using the EASY-Care assessment system as part of their annual health check. There was a high response rate to the standardized assessment in both populations (75% and 79%). Compared to people in south Hampshire, the people in Belfast had higher relative risk of having fair/poor self-rated health, and lower relative risk of having good/sufficient accommodation and of having difficulty chewing. People in Belfast had a higher relative risk of being dependent for six of the seven IADL items and for continence of urine, bathing, grooming, use of the stairs and dressing among the ADL items. The results demonstrate the ability of data generated by assessment system to discriminate between populations of older people when used as part of routine practice. Differences in health and functional status may be associated with deprivation. Data collected during the annual health check about the health and functional status of older people could provide a useful adjunct to census and survey data to measure population needs and to support locality planning. [source]


    Betel quid not containing tobacco and oral cancer: A report on a case,control study in Papua New Guinea and a meta-analysis of current evidence

    INTERNATIONAL JOURNAL OF CANCER, Issue 6 2007
    Steven J. Thomas
    Abstract Smoking and betel quid chewing are associated with increased risk of oral cancer but few studies have reported on associations in populations where betel quid does not contain tobacco. We conducted a case,control study in Papua New Guinea and a systematic review. Our case,control study recruited 143 cases with oral cancer and 477 controls. We collected information on smoking and betel quid chewing. Current smoking was associated with an increased risk of oral cancer with an adjusted odds ratio (OR) for daily smokers of 2.63 (95% confidence intervals (95% CI) 1.32, 5.22) and amongst heaviest smokers of 4.63 (95% CI 2.07, 10.36) compared to never-smokers. Betel chewing was associated with increased risk of oral cancer with an adjusted OR for current chewers of 2.03 (95% CI 1.01, 4.09) and in the heaviest chewers of 2.47 (95% CI 1.13, 5.40) compared to nonchewers. The OR in those who both smoked tobacco and chewed betel quid was 4.85 (95% 1.10, 22.25), relative to those who neither smoked nor chewed. The systematic review identified 10 previous studies that examined risk of oral cancer associated with betel quid chewing that controlled for smoking in populations where betel quid did not contain tobacco. In studies that reported results for non-smokers the combined OR was 2.14 (95% CI 1.06, 4.32) in betel quid chewers and in studies that adjusted for smoking the combined OR was 3.50 (95% CI 2.16, 5.65) in betel quid chewers. Preventive efforts should discourage betel quid chewing as well as smoking. © 2006 Wiley-Liss, Inc. [source]


    Glutathione S -transferase M3 (A/A) genotype as a risk factor for oral cancer and leukoplakia among Indian tobacco smokers

    INTERNATIONAL JOURNAL OF CANCER, Issue 1 2004
    Nilabja Sikdar
    Abstract Polymorphism in glutathione S -transferase (GST) genes, causing variations in enzyme activities, may influence susceptibility to oral cancer and leukoplakia in smokers and/or smokeless tobacco users. In this case-control study consisting of 109 leukoplakia and 256 oral cancer patients and 259 controls, genotype frequencies at GSTM1, GSTT1, GSTM3 and GSTP1 loci were determined by polymerase chain reaction-restriction fragment length polymorphism methods and analyzed by multiple logistic regression to determine the risks of the diseases. There were no significant differences in the distributions of GSTM1, GSTM3 and GSTT1 genotypes in patients and controls when all individuals were compared. In contrast, frequencies of ile/ile genotype at codon 105 and variant val-ala haplotype of GSTP1 was significantly higher (OR = 1.5; 95% CI = 1.0,2.0) and lower (OR = 1.4; 95% CI = 1.0,1.9) in oral cancer patients compare to controls, respectively. The impacts of all genotypes on risks of oral cancer and leukoplakia were also analyzed in patients with different tobacco habits and doses. Increased risks of cancer and leukoplakia were observed in tobacco smokers with GSTM3 (A/A) genotype (OR = 2.0, 95% CI = 1.0,4.0; OR = 2.0, 95% CI = 1.0,4.4, respectively). So, GSTM3 (A/A) genotype could become one of the markers to know which of the leukoplakia would be transformed into cancer. Heavy tobacco chewing (> 124 chewing-year) increased the risk of cancer in individuals with GSTT1 homozygous null genotype (OR = 3.0; 95% CI = 1.0,9.8). Furthermore, increased lifetime exposure to tobacco smoking (> 11.5 pack-year) increased the risk of leukoplakia in individuals with GSTM1 homozygous null genotype (OR = 2.4; 95% CI = 1.0,5.7). It may be suggested that polymorphisms in GSTP1, GSTM1, GSTM3 and GSTT1 genes regulate risk of cancer and leukoplakia differentially among different tobacco habituals. © 2003 Wiley-Liss, Inc. [source]


    Oral health status and treatment needs among school children in Sana'a City, Yemen

    INTERNATIONAL JOURNAL OF DENTAL HYGIENE, Issue 2 2010
    KA Al-Haddad
    To cite this article: Int J Dent Hygiene DOI: 10.1111/j.1601-5037.2009.00398.x Al-Haddad KA, Al-Hebshi NN, Al-Ak'hali MS. Oral health status and treatment needs among school children in Sana'a City, Yemen. Abstract:, Data on the oral health status and treatment needs among Yemeni children are lacking. Objectives:, To assess caries prevalence, treatment needs and gingival health status among school children in Sana'a City and to examine how these are affected by age, gender and khat chewing. Methods:, 1489 children (6- to 14-year old) were randomly selected from 27 schools representing all nine districts of Sana'a City. Dental caries and treatment needs were evaluated using standard WHO oral survey methods. The plaque index (PI), calculus index (CI) and the gingival index (GI), recorded at the six Ramfjord's teeth, were used to assess gingival health status. Results:, 4.1% of the study subjects were caries-free. Prevalence of these was significantly higher among the males. Overall, mean dmfs, dmft, DMFS and DMFT scores were 8.45, 4.16, 3.59 and 2.25 respectively. The decayed component accounted for >85% of the scores. The highest dmfs/dmft means were found among the 6,8 years age group, while the highest DMFS/DMFT means were scored by the 12,14 years age group. The need for restorative treatment and extractions was high; the former was significantly higher among the females. All subjects had gingivitis; the mean PI, CI and GI were 1.25, 0.3 and 1.36 respectively. Khat chewing did not affect caries experience; however, it was significantly associated with higher PI, CI and GI scores. Conclusions:, The prevalence of caries, gingivitis and treatment needs among children in Sana'a city is high. More surveys in other Yemeni cities to generate comprehensive data are required. [source]


    Persistence effects in flavour release from liquids in the mouth

    INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 3 2003
    Kevin M. Wright
    Summary The flavour of drinks, creams and liquid-like food consumed without chewing is an important quality factor for consumers and manufacturers alike, so reliable predictive models of flavour release from liquids in the mouth are highly desirable. In this paper we show how the breath-by-breath concentration of aroma in the headspace after swallowing an aliquot of liquid can be modelled using basic principles of interfacial mass transfer. This mechanistic model is used to fit the experimental data for dilute aqueous solutions of five aroma compounds consumed by trained panellists. It is shown that many aroma compounds give detectable concentrations in the exhaled breath several minutes after swallowing and after ten or more exhalations. The influence of liquid composition on this aroma persistence effect is discussed. [source]


    Tunica albuginea urethroplasty for anterior urethral strictures: A urethroscopic analysis

    INTERNATIONAL JOURNAL OF UROLOGY, Issue 9 2009
    Raj K Mathur
    Objective: To assess the efficacy of tunica albuginea urethroplasty (TAU) for anterior urethral strictures. Methods: We assessed 206 patients with anterior urethral strictures who underwent TAU. The procedure involves mobilization of strictured urethra and laying it open with a dorsal slit. Edges of the slit-open urethra are sutured to edges of the urethral groove with a silicon catheter in situ. Thus in neourethra, the roof is formed by tunica albuginea of the urethral groove. Results were assessed at 6, 12, 24 and 36 months by comparative analysis of patient satisfaction along with retrograde urethrogram, urethrosonogram, uroflowmetry, and were categorized as good, fair and poor. Good and fair results were considered as successful. Thirty patients were taken for postoperative urethroscopic analysis to allow better understanding of both successful and failed cases. Results: Postoperative evaluation at 6 months showed a 96.6% success rate, which decreased to 94.7% at 1 year, 93.2% at 2 years and over 90% at the end of 3 years. The overall failure rate was 9.2%, which required revision surgery. Urethroscopic visualization of the reconstruction site showed wide, patent and distensible neourethra uniformly lined by urothelium over roof formed by tunica albuginea of the corpora cavernosa in successful cases. Failure cases showed diffuse fibrotic narrowing or circumferential scarring. Conclusion: Tunica albuginea is a locally available distensible tissue, sufficient to maintain the patency of the neourethra, without any graft or flap. TAU is easier and useful when patients have unhealthy oral mucosa due to tobacco chewing. [source]


    Frequency of and indications for wholly compensatory nursing care related to enteral food intake: a secondary analysis of the Belgium National Nursing Minimum Data Set

    JOURNAL OF ADVANCED NURSING, Issue 1 2000
    Georges Evers PhD RN
    Frequency of and indications for wholly compensatory nursing care related to enteral food intake: a secondary analysis of the Belgium National Nursing Minimum Data Set This study describes the frequency of and indications used for total feeding assistance and tube feeding in a national representative sample of Belgian hospital patients (n = 421 314). Data from the 1990 national minimum nursing data registration was used. Orem's self-care model was used to describe and categorize types of nursing care and related indications. The scope of wholly compensatory nursing care was limited to total feeding assistance and tube feeding. This type of nursing care is indicated when self-care agency is undeveloped or cannot be used and when self-care demands are significantly increased. Based on review of the literature, hypotheses to indicate nursing care were formulated and tested. Wholly compensatory nursing care related to enteral food intake is given to 14·4% of the total patient population in Belgian hospitals. If self-care demand increases due to malnutrition, then this is an indication for total feeding assistance. If self-care agency decreases due to blindness, mental retardation, disorientation or upper extremity dysfunction, then this is also an indication for total feeding assistance. If self-care agency decreases due to impaired chewing, then this is an indication for tube feeding. This study has generated the first representative national nursing statistics about total feeding assistance and tube feeding in hospitals. [source]


    Relationship between betel quid additives and established periodontitis among Bangladeshi subjects

    JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 1 2008
    Rahena Akhter
    Abstract Aim: To determine the relationship between betel quid chewing additives and established periodontitis in Bangladeshi subjects. Material and Methods: A total of 864 subjects participated in this study. Among them, 140 pairs of sex- and age-matched case subjects and control subjects were selected. A case was defined as a person who had at least two sites with a clinical attachment level (CAL)6 mm and at least one site with probing depth (PD)5 mm. Subjects who did not fulfill these criteria were considered as controls. Information on sociodemographic variables, psychological stress, dental health behaviour, smoking and betel quid chewing habits was obtained. Results: Multiple logistic regression analysis showed that current betel quid chewers had greater probabilities of having established periodontal disease than did non-chewers (odds ratio=3.97, p<0.05). Mean PD, mean CAL, mean percentage of bleeding on probing and number of missing teeth were significantly higher in chewers of betel quid with tobacco and masala than in chewers of betel quid without such additives adjusting for age, sex, smoking habit, body mass index, dental visit pattern, stress and plaque index. Higher frequency and longer duration of betel quid chewing showed a significant relation to an increase in periodontal parameters. Conclusion: The results indicate that betel quid additives might significantly enhance periodontitis in the population studied. [source]


    Adverse effects of arecoline and nicotine on human periodontal ligament fibroblasts in vitro

    JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 3 2001
    Yu-Chao Chang
    Abstract Background, aims: The habit of betel nut chewing impinges on the daily lives of approximately 200 million people. Betel quid chewers have a higher prevalence of periodontal diseases than non-chewers. This study examined the pathobiological effects of arecoline, a major component of the betel nut alkaloids, on human periodontal ligament fibroblasts (PDLF) in vitro. Method: Cell viability, proliferation, protein synthesis, and cellular thiol levels were used to investigate the effects of human PDLF exposed to arecoline levels of 0 to 200 ,g/ml. In addition, nicotine was added to test how it modulated the effects of arecoline. Results: Arecoline significantly inhibited cell proliferation in a dose-dependent manner. At concentrations of 10 and 30 ,g/ml, arecoline suppressed the growth of PDLF by 20% and 50% (p<0.05), respectively. Arecoline also decreased protein synthesis in a dose-dependent manner during a 24-h culture period. A 100 ,g/ml concentration level of arecoline significantly inhibited protein synthesis to only 50% of that in the untreated control (p<0.05). Moreover, arecoline significantly depleted intracellular thiols in a dose-dependent manner. At concentrations of 25 ,g/ml and 100 ,g/ml, arecoline depleted about 18% and 56% of thiols (p<0.05), respectively. This suggests that arecoline itself might augment the destruction of periodontium associated with betel nut use. Furthermore, the addition of nicotine acted with a synergistic effect on the arecoline-induced cytotoxicity. At a concentration of 60 ,g/ml, arecoline suppressed the growth of PDLF by about 33%, and 5 mM nicotine enhanced the arecoline-induced cytotoxic response to cause about 66% cell death. Conclusion: During thiol depletion, arecoline may render human PDLF more vulnerable to reactive agents within cigarettes. Taken together, people who combine habits of betel nut chewing with cigarette smoking could be more susceptible to periodontium damage than betel nut chewing alone. Zusammenfassung Zielsetzung: Das Kauen von Betelnüssen gehört zum Alltag von ungefähr 200 Millionen Menschen. Betelnußkauer weisen eine höhere Prävalenz von Parodontalerkrankungen auf als Personen, die keine Betelnüsse konsumieren. In dieser Studie sollte der pathobiologische Effekt des Arekolins, das die Hauptkomponente des Betelnußalkaloides darstellt, auf menschliche Desmodontalfibroblasten (PDLF) in vitro untersuchen. Material und Methoden: Zellvitalität, Proliferationsrate, Proteinsynthese und zelluläre Thiolspiegel wurden genutzt, um zu untersuchen, welche Auswirkungen eine Exposition der PDLF gegenüber Arekolinspiegeln von 0 bis 200 ,g/ml hat. Zusätzlich wurde Nikotin beigefügt, um festzustellen wie das Nikotin den Effekt des Arekolins beeinflußt. Ergebnisse: Arekolin hemmt die Zellproliferation signifikant in dosisabhängiger Weise. Bei Konzentrationen von 10 und 30 ,g/ml unterdrückt Arekolin das Wachstum der PDLF um 20% bzw. 50% (p<0.05). Arekolin unterdrückt ebenfalls dosisabhängig die Proteinsynthese während der 24-stündigen Kultivierungsperiode. Ein Arekolinspiegel von 100 ,g/ml reduzierte die Proteinsynthese auf 50% im Vergleich zur unbehandelten Kontrollkultur (p<0.05). Auch die intrazellulären Thiolspiegel wurden dosisabhängig reduziert. Bei Konzentrationen von 25 und 100 ,g/ml wurden die Thiolspiegel um 18% bzw. 56% reduziert (p<0.05). Bei einer Konzentration von 60 ,g/ml unterdrückte das Arekolin das PDLF-Wachstum um 33%. Die Zugabe von 5 mM Nikotin verstärkte die durch Arekolin induzierte zytotoxische Wirkung, so daß es zum Zelltot von 66% kam. Schlußfolgerungen: Es scheint, daß Arekolin selbst zu der Schädigung des Parodonts beiträgt, die der Betelnuß zugeschreiben wird. Außerdem deuten die Ergebnisse darauf hin, daß Personen, die Betelnußkauen mit Nikotinkonsum kombinieren, empfindlicher für Schädigungen des Parodonts sind als solche, die nur Betelnüsse kauen. Während der Inaktivierung des Thiols könnte das Arekolin PDLF verletzlicher für andere reaktive Substanzen wie Nikotin machen. Résumé L'habitude de mastiquer de la noix de betel affecte la vie quotidienne de près de 200 millions de personnes. Les mâcheurs de betel présentent une prévalence plus élevée de maladies parodontales. Cette étude examine les effets pathologiques de l'arécoline, un composant majeur des alcaloïdes de la noix de betel, sur des fibroblastes du ligament parodontal humain (PDLF) in vitro. La viabilité cellulaire, la prolifération, la synthèse protéique, et les niveaux cellulaires de thiol ont été utilisés pour observer les effets de l'exposition de PDLF humains à des taux d'arécoline de 0 à 200 ,g/ml. De plus, de la nicotine fut ajouté pour tester la façon dont cela modulait les effets de l'arécoline. L'arécoline inhibait significativement la prolifération cellulaire de façon dose dépendante. A des concentrations de 10 à 30 ,g/ml, l'arécoline supprime la croissance des fibroblastes par 20 et 50% (p<0.05), respectivement. L'arécoline dimunuait également la synthèse des protéines de façon dose dépendante pendant une période de culture de 24 h. Une concentration de 100 ,g/ml d'arécoline inhibit la synthèse protéique à seulement 50% de celle du groupe controle non traité (p<0.05). De plus, l'arécoline réduit les thiols intracellulaires de façon dose dépendante. A des concentrations de 25 ,g/ml et 100 ,g/ml, l'arécoline réduit environ 18 à 56% des thiols, respectivement (p<0.05). Cela suggère que l'arécoline, elle même, peut augmenter la destruction du parodonte en association avec l'utilisation de noix de betel. De plus, l'addition de nicotine entrainait un effet synergique sur la cytotoxicité induite par l'arécoline. A une concentration de 60 ,g/ml, l'arécoline supprimait la croissance des PDLF d'environ 33% et 5 mM de nicotine augmentait cette réponse cytotoxique induite par l'arécoline, jusqu'à entrainer 66% de morts cellulaires. Lors de la réduction des thiols, l'arécoline pourrait rendre les PDLF humains plus vulnérables à des agents réactifs entrant dans la composition des cigarettes. Pris ensemble, les gens qui combinent des habitudes de mastication de noix de betel et de tabagisme, pourrait être plus susceptibles à des dommages parodontaux, que les gens qui utiliserait uniquement la noix de betel, mais sans fumer. [source]


    Immunohistochemical expression of RANKL, RANK, and OPG in human oral squamous cell carcinoma

    JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 10 2009
    Fu-Hsiung Chuang
    Background:, The mechanism of oral squamous cell carcinoma (SCC) invading jawbone remains controversial. Interactions between receptor activator of NF-,B (RANK) and its ligand (RANKL) are required for osteoclastogenesis. The binding of RANK and RANKL induces differentiation of osteoclasts, leading to bony destruction. Osteoprotegerin (OPG), a decoy receptor for RANKL, also binds to RANKL by competing with RANK, and this could protect against osseous destruction. Materials and methods:, Immunoexpression of RANKL, RANK, and OPG in 25 cases of human buccal SCCs without bony invasion and 15 cases of gingival SCCs with mandibular bony invasion was investigated. Normal oral mucosa from five individuals without betel-quid chewing or cigarette smoking was used as a control. The scores are designated as percentage of positive staining × intensity of staining for each section. Results:, Strong cytoplasmic staining of RANKL proteins is detected in cancer cells of both buccal and gingival SCCs. The same protein is identified in cytoplasm of osteoclasts for all cases involving bony invasion. Strong cytoplasmic staining of RANKL is confined to basal layer for all normal mucosa. A similar staining pattern is noted for RANK protein in all buccal and gingival SCCs. An absence of staining of RANK protein is noted for all normal tissues. Weak to negative cytoplasmic stained OPG protein is present in all buccal and gingival SCCs, but is absent in all normal tissues. Conclusion:, These findings suggest the potential value of the RANK/RANKL/OPG pathway as biomarkers in human oral SCCs. [source]


    Areca nut extract-treated gingival fibroblasts modulate the invasiveness of polymorphonuclear leukocytes via the production of MMP-2

    JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 1 2009
    Hsuan-Hsuan Lu
    Background:, Areca nut chewing is associated with an increase in the incidence of oral neoplastic or inflammatory diseases. Aberrations in matrix metalloprotease (MMP) expression are associated with the pathogenesis of oral diseases. This study investigated the potential effects of areca nut extract (ANE) on human gingival fibroblasts and the consequential impacts on inflammatory pathogenesis. Methods:, Analyses of senescence marker, cell viability, changes of the cell cycle, and cell granularity in gingival fibroblasts together with an assessment of the invasiveness of polymorphonuclear (PMN) leukocytes after treatment with the supernatant of ANE-treated gingival fibroblasts were performed to characterize the phenotypic impacts. Western blotting and gelatin zymography were used to assay the expression and activity of MMP-2. Results:, Chronic subtoxic (<10 ,g/ml) ANE treatment resulted in premature growth arrest, appearance of senescence-associated ,-galactosidase activity and various other senescence-associated phenotypes in gingival fibroblasts. Gingival fibroblasts established from older individuals had a higher propensity to become ANE-induced senescent gingival fibroblasts. An activation of MMP-2 was identified in senescent cells. PMN leukocytes treated with the supernatant of ANE-induced senescent cells exhibited a significant increase in invasiveness, which was abrogated by both a MMP-2 blocker and a MMP-2 nullifying antibody. Conclusions:, This study provides evidence whereby MMP-2 secreted from ANE-induced senescent gingival fibroblasts would facilitate the invasiveness of PMN leukocytes, which could be associated with the oral inflammatory process in areca chewers. [source]


    Combinational polymorphisms of four DNA repair genes XRCC1, XRCC2, XRCC3, and XRCC4 and their association with oral cancer in Taiwan

    JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 5 2008
    Ching-Yu Yen
    Background:, Many single nucleotide polymorphisms (SNPs) have been found to be associated with oral cancer but the biological interactions through SNPs are seldom addressed. In this study, we focused on the joint effect for SNP combinations of four DNA repair genes, X-ray repair cross-complementing groups (XRCCs) 1,4, involved in major cancer-related pathways. Methods:, Single nucleotide polymorphism genotyping was determined using by polymerase chain reaction-restriction fragment length polymorphism in this study (case = 103, control = 98). Different numbers of combinational SNPs with genotypes called the pseudo-haplotypes from these chromosome-wide genes were used to evaluate their joint effect on oral cancer risk. Results:, Except for XRCC2 rs2040639-AG, none of these SNPs was found to individually contribute to oral cancer risk. However, for two combined SNPs, the proportion of subjects with oral cancer was significantly higher in the pseudo-haplotype with AG-CC genotypes in rs2040639-rs861539 (XRCC2,XRCC3) compared with those with non-AG-CC genotypes. Similarly, the pseudo-haplotype of rs2040639,rs861539,rs2075685 (XRCC2,XRCC3,XRCC4) and rs2040639,rs861539,rs2075685,rs1799782 (XRCCs 1,4) with specific genotype pattern (AG-CC-TG and CT-AG-CC-TG) among three and four combinational SNPs were significantly associated with oral cancer. After controlling for age, gender, smoking, drinking, and betel nut chewing, the estimated odds ratio of oral cancer were 2.45, 5.03, and 10.10 for two, three and four specific SNP combinations, respectively, comparing these specific pseudo-haplotypes to their corresponding non-pseudo-haplotypes. Conclusion:, We have identified the potential combined XRCCs 1,4 SNPs with genotypes that were associated with oral cancer risk and may have an impact on identification of a high-risk population. [source]


    Oral submucous fibrosis: study of 1000 cases from central India

    JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 1 2007
    V. K. Hazarey
    Background:, Very few reports have been published on the gender specificity of oral submucous fibrosis (OSF) in relation to habit patterns and the severity of disease in the world literature. The purpose of the study was to ascertain the gender specificity for different habits and severity of OSF. Methods:, A hospital-based cross-sectional study on various habit patterns associated with OSF was performed in Nagpur over a 5-year period. A total of 1000 OSF cases from 266 418 out patients comprised the study sample. Results:, The male-to-female ratio of OSF was 4.9:1. Occurrence of OSF was at a significant younger age group (<30 years) among men when compared with women (OR = 4.62, 3.22,6.63, P = 0.0001). Reduced mouth opening, altered salivation and altered taste sensation were found to be significantly more prevalent in women when compared with men. Exclusive areca nut chewing habit was significantly more prevalent in women (OR = 44.5, 25.4,79.8, P = 0.0001). Whereas significant increase for Gutkha (Areca quid with tobacco) (OR = 2.33, 1.56,3.54, P = 0.0001) and kharra/Mawa (crude combination of areca nut and tobacco) (OR = 6.8, 4.36,11.06, P = 0.0001) chewing was found in men when compared with women. Conclusions:, There is a marked difference in literacy, socioeconomic status, areca nut chewing habits, symptoms and disease severity in women when compared with men in the central Indian population. [source]


    Effect of betel chewing, tobacco smoking and alcohol consumption on oral submucous fibrosis: a case,control study in Sri Lanka

    JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 4 2006
    A. Ariyawardana
    Background:, Oral submucous fibrosis (OSMF) is a chronic, insidious, disabling potentially malignant condition of the oral mucosa seen predominantly in south and Southeast Asia. No reports are hitherto available on the aetiological factors of OSMF based on Sri Lankan patients. Methods:, A total of 74 patients with OSMF and 74 controls who consecutively attended the Oral Medicine clinic at the Dental Hospital (Teaching) Faculty of Dental Sciences, University of Peradeniya, Sri Lanka were included in the study. Binary logistic regression analyses were performed to model the influence of betel chewing, smoking and alcohol use and to determine the effects of different combinations of chewing habits on OSMF. Results:, Betel chewing was the only significantly associated factor in the aetiology of OSMF (OR = 171.83, 95% CI: 36.35,812.25). There were no interaction effects of chewing, smoking and alcohol consumption in the causation of OSMF. Conclusion:, The present study has shown a strong association of betel quid chewing (including tobacco as an ingredient) with the causation of OSMF. [source]


    Synergistic effects of nicotine on arecoline-induced cytotoxicity in human buccal mucosal fibroblasts

    JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 8 2001
    Yu-Chao Chang
    Abstract: Areca quid chewing has been linked to oral submucous fibrosis and oral cancer. Arecoline, a major areca nut alkaloid, is considered to be the most important etiologic factor in the areca nut. In order to elucidate the pathobiological effects of arecoline, cytotoxicity assays, cellular glutathione S-transferase (GST) activity and lipid peroxidation assay were employed to investigate cultured human buccal mucosal fibroblasts. To date, there is a large proportion of areca quid chewers who are also smokers. Furthermore, nicotine, the major product of cigarette smoking, was added to test how it modulated the cytotoxicity of arecoline. At a concentration higher than 50 ,g/ml, arecoline was shown to be cytotoxic to human buccal fibroblasts in a dose-dependent manner by the alamar blue dye colorimetric assay (P<0.05). In addition, arecoline significantly decreased GST activity in a dose-dependent manner (P<0.05). At concentrations of 100 ,g/ml and 400 ,g/ml, arecoline reduced GST activity about 21% and 46%, respectively, during a 24 h incubation period. However, arecoline at any test dose did not increase lipid peroxidation in the present human buccal fibroblast test system. The addition of extracellular nicotine acted synergistically on the arecoline-induced cytotoxicity. Arecoline at a concentration of 50 ,g/ml caused about 30% of cell death over the 24 h incubation period. However, 2.5 mM nicotine enhanced the cytotoxic response and caused about 50% of cell death on 50 ,g/ml arecoline-induced cytotoxicity. Taken together, arecoline may render human buccal mucosal fibroblasts more vulnerable to other reactive agents in cigarettes via GST reduction. The compounds of tobacco products may act synergistically in the pathogenesis of oral mucosal lesions in areca quid chewers. The data presented here may partly explain why patients who combined the habits of areca quid chewing and cigarette smoking are at greater risk of contracting oral cancer. [source]


    Copper stimulates human oral fibroblasts in vitro: a role in the pathogenesis of oral submucous fibrosis

    JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 8 2001
    C. Trivedy
    Abstract: Copper is implicated in the pathogenesis of several fibrotic disorders. Areca nut has been shown to have a high copper content and areca chewing is associated with oral submucous fibrosis (OSF). The effects of copper on human oral fibroblasts were investigated in vitro. Human oral fibroblasts were incubated with copper chloride (CuCl2) at concentrations ranging from 0.01 ,M to 500 ,M for 24 h, and in vitro cell proliferation was assayed by incorporation of tritiated,thymidine; soluble and non-soluble collagen synthesis was assayed using tritiated-proline. Addition of copper chloride at concentrations ranging from 0.1 ,M to 50 ,M increased the collagen synthesis by the oral fibroblasts compared with growth without copper (P<0.05). The addition of copper chloride neither increased the synthesis of non-collagenous proteins by the fibroblasts nor influenced their proliferation rate. We conclude that copper upregulates collagen production in oral fibroblasts. This appears to be concentration dependent, with peak collagen synthesis at 50 ,M CuCl2. These in vitro results taken together with the recent findings of copper in oral biopsies from OSF subjects support the hypothesis that copper in areca nut acts as a mediator of OSF. [source]


    Measurement of jerk-cost using a triaxial piezoelectric accelerometer for the evaluation of jaw movement smoothness

    JOURNAL OF ORAL REHABILITATION, Issue 8 2010
    I. MINAMI
    Summary, Jerk-cost as a measure of jaw movement smoothness has been used to evaluate the masticatory function of patients with tooth loss and malocclusion. Jerk-cost measuring systems have thus far been unable to determine the jerk-cost of each chewing phase over time. The purposes of this study were (i) to develop a new method for measuring momentary jerk-cost of the jaw movement using a small triaxial piezoelectric accelerometer and (ii) to test the hypothesis that the lowest smoothness is seen during jaw-opening phase. The accelerometer was attached to the skin of the mentum of each subject. Vertical jaw displacement, acceleration, the jerk, and the time differential of jerk-cost during gum chewing were analysed as a function of time in five normal dentate subjects (n = 5). The system revealed intra-class correlation coefficients of intra-examiner, inter-examiner, and test,retest consistency of substantially high values (0·80,0·88). In all subjects, the highest jerk-cost was observed in the opening phase of each chewing cycle when the gum was parting from the teeth; the lowest jerk-cost was observed in the intercuspal phase throughout the chewing cycle, thus confirming the hypothesis. Significant differences were observed between the opening, closing, and intercuspal chewing phases (N = 5, P = 0·007). The smoothness measurement system used in this study evaluated the momentary smoothness of each chewing phase in the masticatory cycle. The system may serve as a diagnostic tool to evaluate the smoothness of the jaw movement in general dental practice. [source]


    Masticatory jaw movement optimization after introduction of occlusal interference

    JOURNAL OF ORAL REHABILITATION, Issue 3 2010
    K. YASHIRO
    Summary, How ,control' characteristics of masticatory jaw movement, such as skilfulness of the movement, change after alteration in occlusion remains uncertain. For each of 10 healthy adults with good occlusion, an occlusal interference with artificial ,tooth-cusp' was introduced to the crown of the upper molar tooth on the non-working side of unilateral chewing. Mandibular incisor-point movements were then recorded by a 3D tracking device. The introduction of the occlusal interference induced a remarkable increase in the normalized jerk-cost (NJC), prolonged duration of the decelerative phase and lowered peak velocity for jaw closing movement during chewing. Overall, the NJC and velocity profile showed significant recoveries during the course of about 90 repetitive chewing cycles performed under the altered occlusal condition. These findings suggest that acute adaptive changes of jaw motion after introduction of occlusal interference might be characterized as the recovery process of movement skilfulness in terms of movement smoothness and velocity profile. [source]


    Distance of the contact glide in the closing masticatory stroke during mastication of three types of food

    JOURNAL OF ORAL REHABILITATION, Issue 8 2009
    B. RILO
    Summary, This study was designed to characterize the distance of the contact glide in the closing masticatory stroke in healthy adult subjects, during chewing of three types of food (crustless bread, chewing gum and peanuts). Mandibular movements (masticatory movements and laterality movements with dental contact) were registered using a gnathograph (MK-6I Diagnostic System) on the right and left side during unilateral chewing of the three food types. Length of dental contact was measured in masticatory cycle, which is defined as where the terminal part of the chewing cycles could be superimposed on the pathways taken by the mandible during lateral excursions with occlusal contacts. The length of dental contact during mastication of chewing gum is 1·46 ± 1 mm, during chewing of soft bread is 1·38 ± 0·7 mm and during chewing of peanuts is 1·45 ± 0·9 mm. There is no significant difference in the lengths of dental contact during mastication of three types of foods that enable direct tooth gliding. [source]


    Motor control of jaw muscles in chewing and in isometric biting with graded narrowing of jaw gape

    JOURNAL OF ORAL REHABILITATION, Issue 10 2008
    P. A. PRÖSCHEL
    Summary, When a certain bite force is applied during unilateral chewing, the combination of jaw elevator muscle activities is different than when a comparable force is applied in unilateral isometric biting, e.g. on a force transducer. Masticatory peak force is generated in a nearly isometric phase of the chewing cycle, with a jaw gape of about 1 mm. In contrast, peak force in isometric biting on force measuring equipment usually induces jaw gapes of 6 mm or even more. Therefore, we tested the hypothesis that the jaw gape influences relative activation of elevator muscles in unilateral isometric biting. We further examined whether such influence could explain the different activity combinations of chewing and isometric biting. In thirty asymptomatic males, masseter and temporalis activities were recorded during intermittent isometric biting with jaw gapes of 6, 5, 3, 2 and 1 mm and during unilateral chewing. Activity combinations were described by working/balancing ratios and by temporalis/masseter ratios. With decreasing jaw gape the working/balancing ratio of the posterior temporalis decreased (P < 0·002) while that of the masseter increased (P < 0·001). Likewise, the temporalis/masseter ratio on the balancing side increased (P < 0·001). With decreasing jaw gape, activity ratios of isometric biting approached ratios of chewing. We conclude that: (i) relative jaw muscle activation in isometric biting depends on the jaw gape, (ii) relative muscle activation in chewing resembles relative activation of isometric biting with a small ,chewing-like' gape. This suggests that characteristic activity combinations in chewing are mainly a result of the approximately isometric contraction during the slow closing phase of the chewing cycle. [source]