The study design was a cross-over study as the same group received acupressure at different points during the study; it was carried out during a period of 6 months from October 2017-March 2018 after Receiving Approval from Institutional Ethics Committee (ref no- DMIMSU(DU)/IEC/2017-18/6767). Sample size was decided by using the method of difference of means, and the power of the study was 80%.

The observer of the study was blinded in all the phases. Thirty students fulfilling the inclusion and exclusion criteria’s studying in scond year BDS Sharad Pawar Dental College and Hospital, Sawangi, Maharashtra, India, were included in the study.

Students between the age group of 18-28 years providing with written consent were considered for the study. The subjects involved were the ones having no prior knowledge regarding role of acupressure in controlling severity of gag reflex. The predictive gagging survey was administered, and subjects scoring 7 or more than 7 were included in the study [7].

Subjects who were partially edentulous and had abnormalities of palate and lips. Subjects with systemic disorders and co-morbidities affecting psychomotor function. Patients who were aware of acupressure as a modality to control gag reflex were also excluded.

Disposable Wooden spatula, Custom made Acupressure bands for chin and wrist, Disposable Sickness bags, Paper Towels.

The two points which were to be checked for controlling of gag reflex were P-6 and CV-24. In order to eliminate bias a Placebo point was added to the study. The Placebo point served the purpose of blinding the subject and also the observant. It also helped in providing an unbiased statistical result. The study was conducted in 3 phases separated by period of 1 week. During each phase, all the subjects were randomly tested at the acupressure points in such a way that all three points were tested in all the subjects. The observer was unknown to the identity of points and for this purpose the points were named A (P-6), B (CV-24) and C (Placebo). The gag reflex was triggered using disposable wooden spatula at the gag trigger zone; once a gag response was elicited, the trigger was removed. The gag trigger zones triggered were posterior pharyngeal wall, Posterior Faucial Pillar, anterior faucial pillar, palatoglossal arch and Internal Cheek [2]. The patients were graded according to the gag severity index by Fiske J, Dickinson C [8]. The patient was rested for 1-2 minutes to recover from the gag experienced and the pressure was applied on the respective points for 5 minutes and gag response was again checked and scaled on the gag severity index. ([Table/Fig-1] shows the outline of the procedure).

[Table/Fig-2]:

Location of acupressure points considered in the study.

A F-Cun (finger-cun) in a measurement relative to the patient’s body that is used to find acupuncture points [9].

1 F-cun=space between the distal phalangeal joint and the proximal interphalangeal joint of the middle finger.

Location of the point P-6 [10,11]: A 2 cun above the transverse crease on the wrist on the palmar aspect of the forearm, on the line connecting Pericardium 7 and Pericardium 3 points, between the tendons of musculus flexor carpi radialis and musculus palmaris longus [Table/Fig-2a].

Location of the point CV-24 [10]: On the face, below the lower lip on the midline, in the depression (the mento-labial groove) between the point of the chin and the lower lip [Table/Fig-2b].

Location of placebo point: On the Right Arm 5 cm above elbow on the tricep brachii muscle [Table/Fig-2c].

Custom made bands were used to apply pressure over the fixed points at an area less than 2 mm² [Table/Fig-3a-c].

[Table/Fig-3]:

Application of acupressure at Point P-6, CV-24 and placebo using customised bands.

The data recorded was tabulated, descriptive and inferential statistical analysis was carried out using chi-square test. The programmes used in the analysis was GraphPad Prism 6.0 version with p<0.05 considered as level of significance. Chi-Square test was used to compare the effects at each point [Table/Fig-4].

From the above statistical analysis, it was observed that as (p<0.05) is the level of significance. Out of the 30 subjects, the results were tabulated for pre-application and post-application of acupressure at the respective points. It was found that Point A and Point B were significantly effective in reducing the severity of GR. Point C demonstrated insignificant results. CV-24 is more effective than P6 in controlling the GR in adults within the set age group of 18-28 years of age.

Several Points are discussed in literature for elimination of gag reflex. Studies have shown that Point P6 has remarkable anti-gagging effect [6,10-14]. Another point i.e., Point CV-24 has been proven to be effective in controlling gag reflex its efficacy has been proven in many studies [3,10,13]. The current study has described acupressure at CV-24 and P-6 as effective in controlling severity of gag reflex, this is in concordance with the study performed by Sari E and Sari T who evaluated 45 subjects at point CV-24 and P-6 [10]. Similar results were obtained in a case series of 20 subjects by Bilello G, Fregapane A, who evaluated the efficacy of CV-24 and P-6 in controlling GR on a visual analogue scale pre and post impression making procedure [13]. There are studies which have compared synergistic use of P-6 and CV-24 against use of CV-24 point and the synergism provided better results when compared to singular CV-24 point [10]. There is no study which has compared the efficacy of the points considered in the present study. There is a need to give some information about the safety of acupuncturing; incorrect insertion of acupuncture needle might cause serious adverse events and injury to the tissue. Furthermore, the cross-infection of the hepatitis B or HIV are the other threatening adverse effects of using unsterilized needles. The risk of these infections have been severely curtailed due to the awareness about using disposable needles by health care professional, however the minimum risk probability still exists. These are a few rationales for choosing acupressure over acupuncture [12,15]. Acupressure have been found to be equally effective according to a meta-analysis performed between acupuncture, acupressure, laser acupuncture, and Electrical Stimulation (ETS) in controlling postoperative vomiting in children [16]. The device designed for application of acupressure in this study is made up of auto-polymerising resin, wrist band and Velcro. Advantage being ease of fabrication, non-invasive and its universal fit. It was made in such a way that a projection not exceeding 2 mm² was present which would be in contact during the fastened state. Some studies have shown that females have higher incidence of gagging as compared to males [17]. Interviewer/observer bias was eliminated by addition of a placebo point in the study which was known to the researcher but not the observer and the subjects.

The study was done in a selected age group; extensive studies for longer period of time will yield more significant results. There are many other points documented which are not considered in the present study, the efficacy of those points remains unknown. The acupressure device used in this study had no standard measurement of pressure which is applied. The present study has not taken gender predilection under consideration. Acupressure as a modality for controlling gag reflex has not been compared with other management modalities.

Compelling Literature exists to support the observations of the study, which points out that Acupressure can be effectively used as an adjuvant in controlling the severity of gag-reflex. The method described has no significant downside and can be easily used with no special expertise. The acupressure points considered in the study are effective in controlling the gag reflex, CV-24 is more effective in controlling gag reflex than P-6.

The study can further be extended by using various methods of inducing acupressure at the described points. Intergroup comparison between acupressure and other modalities can also further enhance the knowledge regarding modalities to control gag reflex.