Study protocol for a randomized clinical trial to evaluate the effect of the use of Xylitol gum in the prevention of caries lesions in children living in Ladakh – the Caries Prevention Xylitol in Children (CaPreXCh) trial

Abstract Background: Ladakh is region of the larger region of Kashmir and Jammu administered by India. Only few data on oral health of Ladakh’s population are available. The aim of the present protocol will be to record the caries prevalence of primary and permanent molars of schoolchildren living in Ladakh and to implement a school-based Xylitol program, named the Caries Prevention Xylitol in Children (CaPreXCh) trial, using chewing gums. Methods: The protocol is designed as a triple-blind randomized, controlled, parallel-group clinical trial in children aged 5-14 years. The study should have be carried out from August 2021 to August 2024 in Zanskar Valley (Ladakh), but COVID-19 pandemic does not allow today to make predictions on the exact start. Participants will be randomly allocated into two groups: subjects who will receive a chewing gum with Xylitol (70% w/v) as only sweetener, and those who will a sugared chewing gum containing Maltitol (23% w/v). The subjects will be instructed to chew a total of 6 pellets for 5 min divided into 3 intakes a day (2 in the morning, 2 after the midday meal and 2 in the afternoon) for one school-year. Clinical examination will comprise an oral examination in which caries index (ICDAS scores), bleeding on probing and plaque pH evaluation after sucrose challenge will be recorded at baseline (t0); clinical examination will be repeated after 12 months since the beginning of the chewing gum administration period (t1), after another 12 months period (t2) and finally after further 12 months (t3) (24 months from the end of the chewing gum use). The primary outcome will be the caries increment measured both at enamel and dentinal level on primary and permanent molars. Data analysis will be conducted through Kaplan-Meyer graphs to evaluate caries increment. A comparison of the methods will be carried-out with Cox regression with shared frailty. The net caries increment for initial, moderate and severe caries level, using ICDAS (Δ-initial, Δ-moderate and Δ-severe), will be calculated. Discussion: This trial will be the first trial in India assessing the effect of chewing gum containing only Xylitol as sweetener for caries prevention in children. Name of the registry Clinical trials.gov ClinicalTrials.gov Identifier: NCT04420780 Registered June 9, 2020