The influence of excessive chewing gum use on headache frequency and severity among adolescents

A concise review of chewing gum as an anti-cariogenic agent

Chewing gum has been endorsed as a caries preventive agent by the FDI World Dental Federation, the American Dental Association, and the European Food Safety Authority. This review discusses the mechanism and provides an update of the use of chewing gum for caries prevention. Chewing gum typically consists of a water-insoluble gum base, water-soluble added ingredients, and active ingredients. It can be classified as sugar-containing or sugar-free, as well as nonmedicated or medicated. Chewing gum prevents dental caries through a range of mechanisms, including the clearance of the oral cavity, neutralization of oral acidity, inhibition of cariogenic bacterial growth, remineralization of enamel, and reduction of appetite. Recent clinical studies have evaluated the efficacy of sugar-free chewing gum for caries prevention, with most demonstrating positive results, although some studies have reported contradictory outcomes. To achieve optimal caries prevention, it is generally recommended that individuals chew sugar-free gum for five minutes after meals, three times daily.

Chewing gum for enhancing early recovery of bowel function after caesarean section

BACKGROUND

Caesarean sections (CS) are the most frequent major surgery in the world. A transient impairment of bowel motility is expected after CS. Although this usually resolves spontaneously within a few days, it can cause considerable discomfort, require symptomatic medication and delay hospital discharge, thus increasing costs. Chewing gum in the immediate postoperative period is a simple intervention that may be effective in enhancing recovery of bowel function in other types of abdominal surgeries.

OBJECTIVES

To assess the effects of chewing gum to reduce the duration of postoperative ileus and to enhance postoperative recovery after a CS.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (20 June 2016), LILACs (20 June 2016), ClinicalTrials.gov (20 June 2016), WHO International Clinical Trials Registry Platform (ICTRP) (20 June 2016) and the reference lists of retrieved studies.

SELECTION CRITERIA

All randomised controlled trials comparing chewing gum versus usual care, for women in the first 24 hours after a CS. We included studies published in abstract form only.Quasi-randomised, cross-over or cluster-randomised trials were not eligible for inclusion in this review.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected the studies for inclusion, extracted data and assessed the risk of bias following standard Cochrane methods. We present dichotomous outcome results as risk ratio (RR) with 95% confidence intervals (CI) and continuous outcome results as mean differences (MD) and 95% CI. We pooled the results of similar studies using a random-effects model in case of important heterogeneity. We used the GRADE approach to assess the overall quality of evidence.

MAIN RESULTS

We included 17 randomised trials (3149 participants) conducted in nine different countries. Seven studies (1325 women) recruited exclusively women undergoing elective CS and five studies (833 women) only included women having a primary CS. Ten studies (1731 women) used conventional feeding protocols (nil by mouth until the return of intestinal function). The gum-chewing regimen varied among studies, in relation to its initiation (immediately after CS, up to 12 hours later), duration of each session (from 15 to 60 minutes) and number of sessions per day (three to more than six). All the studies were classified as having a high risk of bias due to the nature of the intervention, women could not be blinded and most of the outcomes were self-reported.Primary outcomes of this review: for the women that chewed gum, the time to passage of first flatus was seven hours shorter than those women in the 'usual care' control group (MD -7.09 hours, 95% CI -9.27 to -4.91 hours; 2399 women; 13 studies; random-effects Tau² = 14.63, I² = 95%, very low-quality evidence). This effect was consistent in all subgroup analyses (primary and repeat CS, time spent chewing gum per day, early and conventional feeding protocols, elective and non-elective CS and time after CS when gum-chewing was initiated). The rate of ileus was on average over 60% lower in the chewing-gum group compared to the control (RR 0.39, 95% CI 0.19 to 0.80; 1139 participants; four studies; I² = 39%, low-quality evidence). Tolerance to gum-chewing appeared to be high. Three women in one study complained about the chewing gum (but no further information was provided) and none of the studies reported adverse effects (eight studies, 925 women, low-quality evidence).Secondary outcomes of this review: the time to passage of faeces occurred on average nine hours earlier in the intervention group (MD -9.22 hours, 95% CI -11.49 to -6.95 hours; 2016 participants; 11 studies; random-effects Tau² = 12.53, I² = 93%, very low-quality evidence). The average duration of hospital stay was shorter in the intervention compared to the control group (MD -0.36 days, 95% CI -0.53 to -0.18 days; 1489 participants; seven studies; random-effects Tau² = 0.04, I² = 92%). The first intestinal sounds were heard earlier in the intervention than in the control group (MD -4.56 hours, 95% CI -6.18 to -2.93 hours; 1729 participants; nine studies; random-effects Tau² = 5.41, I² = 96%). None of the studies assessed women's satisfaction in relation to having to chew gum. The need for analgesia or antiemetic agents did not differ between the intervention and control groups (average RR 0.50, 95% CI 0.12 to 2.13; 726 participants; three studies; random-effects Tau² = 0.79, I² = 69%).

AUTHORS' CONCLUSIONS

This review found 17 randomised controlled trials (involving 3149 women). We downgraded the quality of the evidence for time to first passage of flatus and of faeces and for adverse effects/intolerance to gum chewing because of the high risk of bias of the studies (due to lack of blinding and self-report). For time to first flatus and faeces, we downgraded the quality of the evidence further because of the high heterogeneity in these meta-analyses and the potential for publication bias based on the visual inspection of the funnel plots. The quality of the evidence for adverse effects/tolerance to gum chewing and for ileus was downgraded because of the small number of events. The quality of the evidence for ileus was further downgraded due to the unclear risk of bias for the assessors evaluating this outcome.The available evidence suggests that gum chewing in the immediate postoperative period after a CS is a well tolerated intervention that enhances early recovery of bowel function. However the overall quality of the evidence is very low to low.Further research is necessary to establish the optimal regimen of gum-chewing (initiation, number and duration of sessions per day) to enhance bowel function recovery and to assess potential adverse effects of and women's satisfaction with this intervention. New studies also need to assess the compliance of the participants to the recommended gum-chewing instructions. Future large, well designed and conducted studies, with better methodological and reporting quality, will help to inform future updates of this review and enhance the body of evidence for this intervention.

Lifestyle Factors and Migraine in Childhood

Migraine is one of the most common pain symptoms in children. Indeed, a high percentage of adult migraine patients report to have suffered from recurrent headache during the childhood. In particular, children could experience the so-called childhood periodic syndromes (such as cyclic vomiting, abdominal migraine, and benign paroxysmal vertigo) that have been usually considered precursors of migraine or they could develop overt migraine headaches. However, typical cohort of migraine symptoms could be absent and children could not achieve all clinical features necessary for a migraine attack diagnosis according to classification criteria. Nevertheless, migraine is characterized also in childhood by a significant negative impact on the quality of life and a high risk of developing chronic and persistent headache in adulthood. Several studies have emphasized the role of different risk factors for migraine in children. Among these, obesity and overweight, particular food or the regular consumption of alcohol or caffeine, dysfunctional family situation, low level of physical activity, physical or emotional abuse, bullying by peers, unfair treatment in school, and insufficient leisure time seem to be strictly related to migraine onset or progression. Consequently, both identification and avoidance of triggers seem to be mandatory in children with migraine and could represent an alternative approach to the treatment of migraine abstaining from pharmacologic therapies.

Migraine and lifestyle in childhood

Migraine is one of the most frequently reported somatic complaints in childhood, with a negative impact on health-related quality of life. The incidence of migraine in childhood has substantially increased over the past 30 years, probably due to both increased awareness of the disease and lifestyle changes in this age group. Indeed, several conditions have been identified as risk factors for migraine in childhood. Amongst these, dysfunctional family situation, the regular consumption of alcohol, caffeine ingestion, low level of physical activity, physical or emotional abuse, bullying by peers, unfair treatment in school and insufficient leisure time seem to play a critical role. Nevertheless, there are only few studies about the association between migraine and lifestyle in childhood, due to previous observations specifically focused on "headache" in children. In this brief review, we will concentrate upon recent studies aimed to explore migraine and lifestyle risk factors in childhood.

EFFECT OF GUM CHEWING ON AIR SWALLOWING, SALIVA SWALLOWING AND BELCHING

BACKGROUND

Eructation is a physiologic event which allows gastric venting of swallowed air and most of the time is not perceived as a symptom. This is called gastric belching. Supragastric belching occurs when swallowed air does not reach the stomach and returns by mouth a short time after swallowing. This situation may cause discomfort, life limitations and problems in daily life.

OBJECTIVE

Our objective in this investigation was to evaluate if gum chewing increases the frequency of gastric and/or supragastric belches.

METHODS

Esophageal transit of liquid and gas was evaluated by impedance measurement in 16 patients with complaint of troublesome belching and in 15 controls. The Rome III criteria were used in the diagnosis of troublesome belching. The esophageal transit of liquid and gas was measured at 5 cm, 10 cm, 15 cm and 20 cm from the lower esophageal sphincter. The subjects were evaluated for 1 hour which was divided into three 20-minute periods: (1) while sitting for a 20-minute base period; (2) after the ingestion of yogurt (200 mL, 190 kcal), in which the subjects were evaluated while chewing or not chewing gum; (3) final 20-minute period in which the subjects then inverted the task of chewing or not chewing gum. In gastric belch, the air flowed from the stomach through the esophagus in oral direction and in supragastric belch the air entered the esophagus rapidly from proximal and was expulsed almost immediately in oral direction. Air swallows were characterized by an increase of at least 50% of basal impedance and saliva swallow by a decrease of at least 50% of basal impedance, that progress from proximal to distal esophagus.

RESULTS

In base period, air swallowing was more frequent in patients than in controls and saliva swallowing was more frequent in controls than in patients. There was no difference between the medians of controls and patients in the number of gastric belches and supragastric belches. In six patients, supragastric belches were seen at least once during the 20-minute base period. None of the controls had supragastric belches. In the control group, the ingestion of yogurt caused no significant alteration in the number of air swallows, saliva swallows, gastric belches and supragastric belches. In the patient group, there was an increase in the number of air swallows. If the subjects were chewing gum during this 20-minute period, there was an increase in the number of saliva swallows in both groups, without alterations of the number of air swallow, gastric belches and supragastric belches. There was no alteration in the number of the saliva swallows, air swallows, gastric belches and supragastric belches in both groups for subjects who did not chew gum in the 20-40 minute period after yogurt ingestion. When the subjects were chewing the gum, there was an increase in saliva swallows in the control and patients groups and in air swallows in the patients group.

CONCLUSION

Gum chewing causes an increase in saliva swallowing in both patients with excessive belching and in controls, and an increase in air swallowing in patients with excessive belching 20 minutes after yogurt ingestion. Gum chewing did not increase or decrease the frequency of gastric or supragastric belches.

Headache in school age

Headache, especially migraine and tension-type headache, is one of the most frequently reported somatic complaints by children and adolescents. Different population-based studies have been conducted to study the correlation between headache and lifestyles in pediatric age, nevertheless, the obtained results are often controversial and these relationship still remain unclear. Likewise, is still strongly debated the burden of headache during school age, its impact on school performances and on quality of life of children and their families. Consequently, larger studies are necessary to evaluate the degree of disability due to pediatric headache. We summarize the ongoing knowledge about these concepts, with the intent to provide useful data to neurologists but also to primary care providers, to further improve the management of pediatric headaches by preventing the headache progression, the disabling effects associated and improving the long-term outcome.