The American Academy of Pediatric Dentistry (AAPD) and the European Academy of Paediatric Dentistry (EAPD) do agree that oral hygiene measures should be implemented no later than the eruption of the first primary tooth. Parents should perform or assist with brushing in preschool children using a toothbrush adapted to the child’s age, with a fluoride toothpaste amount that varies according to the child’s age ^[1][47].

The AAPD recommends, in children under the age of three, a smear or rice-sized amount of fluoridated toothpaste, while in children ages three to six, a pea-sized amount of fluoridated toothpaste ^[2][48]. The EAPD recommends the same amount of toothpaste in preschoolers but with 1000 ppm of fluoride ^[3][49]. Both authorities agree that after brushing, rinsing with water should be kept to a minimum or avoided to maximize the protective effect of fluoride.

According to Marinho in 2009 the use of fluoridated toothpaste has the highest caries preventive effect when compared to brushing frequency, supervised toothbrushing and fluoride concentration, highlighting the importance of implementing this procedure on a daily basis ^[4][50]. EAPD recommends, also in preschool children, brushing for more than one minute, reaching every tooth surface.

According to the values reported in Table 1, the use of fluoride toothpaste displays a huge variability among different countries and population subgroups. The most striking result is that in many of the included studies, a large part of the sample was unaware of the kind of toothpaste used. Therefore, it is arguable that, if a patient is unaware of the presence of fluoride in his toothpaste, he is probably unaware of the optimal dose according to age. Several authors agree that the widespread use of fluoride toothpaste is one of the key factors in the decrease in carious lesions in the specific society ^[5][51].

^][21]. The results reported by Gussy et al. in 2008 ^[15][59] report that in his study group of 308 Australian caregivers there was confusion about whether a fluoride paste should be used at all with toddlers. The majority of parents (55%) did not know whether fluoridated toothpastes should be used with toddlers, 31% believed they should not and 13% believed they should be used ^[15][59]. According to what was recently reported in a Brazilian cohort, educational programs and interventions had positive effects on children’s oral health-related behaviors and caregivers’ oral health knowledge, improving fluoride toothpaste use in the right amount according to the age of the intervention group ^[16][60].

In many countries early preventive dental care is generally not performed in preschool children; current literature reports that this is the result of several factors, including: lack of knowledge and awareness of the importance of primary teeth, parents’ dental fear and popular misconceptions about dental care ^[17][61]. Roberts & Codon reported how participants in a UK survey believe that oral health care is simple, common sense and something everyone knew, without considering the importance of being properly educated in this field ^[18][62]. Although it is the desire and interest of parents that their child is at his or her best and their teeth are healthy, the result of this mindset is they do not seek further preventive care information or advice, and the information offered to parents is frequently considered opportunistic ^[18][62].

As reported in Table 2 in most of the available studies, the frequency of brushing is still suboptimal even in European countries. Although the number of people who brush less than once a day is significant but low, in most countries the majority of the population brush only once a day at preschool age. It is therefore clear how the awareness of toothbrushing guidelines is low or, at least, they are not properly enforced.

Alvey in a study on 119 first-time English-speaking pregnant women interviewed before and 12 months after birth highlighted how knowledge regarding fluoride exposure between the cohorts concerning fluoride exposure displayed a significant percentage of mothers who have not implemented this prescribed practice. About one-third of the participants neither intended to implement a fluoridated toothpaste nor ever used fluoridated toothpaste ^[13][58]. According to Nguyen in 2017, parents show mixed and limited knowledge and beliefs about the role of fluoride in caries prevention despite the large body of evidence on the effect of fluoride ^[10][56].

In Germany, for example, there is a lack of consensus among pediatricians and dentists regarding proper use and the amount of fluoride that should be contained in toothpastes for children 0 to 3 years old. The German Society of Oral and Maxillofacial Surgery, in agreement with the AAPD and the EAPD, recommends that baby’s tooth brushing using a fluoride-enriched toothpaste should start when the first tooth emerges. If a child is able to spit toothpaste, the German Society of Paediatrics and Adolescent Medicine and the German Academy for Paediatrics and Adolescent Medicine suggest that he or she begin using it by the age of 4. Persistent failure to agree on the preventive procedures in the first 3 years of life could lead to parental uncertainty about the benefit of fluoride ^[14][41].

According to what Prabhu et al. 2013 highlighted, most of the parents involved in the sample (76%), despite the regular use of toothpaste, are unaware of which kind of fluoride toothpaste they are using to brush their children’s teeth ^[12

As reported in Table 4, it can be noticed that parents are generally not aware of the correct age to start brushing their child’s teeth. A survey in a sample of North American parents revealed that only a small percentage of parents (25.7%) actually know the starting age when a child should start receiving healthcare, and again a low percentage of correct answers were recorded regarding when a mother should start brushing a child’s teeth (32.4%). The authors speculated that these percentages may be the result of the low consideration that mothers may place on taking care of children’s primary teeth ^[34][76].

As clearly stated in the guidelines of both the AAPD and the EAPD, the role of caregivers is to assist in and perform good oral hygiene practices their children under the age of six years.

According to the result of the evidence resumed in Table 3, the percentage of caregivers who do not assist their children while brushing or that supervise them on a non-daily basis is very high. As reported by Huebner et al. 2010 ^[31][73], not assisting children’s oral hygiene can not only reflect a lack of guidelines knowledge, but be the result of a series of personal barriers or external constraints. Personal barriers are the wrong oral health beliefs (tooth brushing is harmful to enamel), children’s emotional reactions, low caregivers’ self-standard of care, or lack of manual skills. On the other hand, external constraints are related to busy modern life and tight daily schedules. It is worth underlining that, in the Huebner study population, almost all (91%) parents considered that brushing child’s teeth twice a day was reasonable. However, in practice little more than half (55%) claimed to have reached the goal ^[31][73].

Scientific data based on self-report have to be handled with care; the results may, in fact, be an overestimate due to social desirability response bias, h is a common problem to take into account in this type of study.

Nuñez Correia et al. in 2017, exploring the plans that mothers-to-be had about their children’s dental care, underlined that 26.1% of the participants did not think about when to begin cleaning their children’s teeth, while 7.8% were uncertain about the timing ^[39][81]. Almost half of the mothers interviewed correctly intended to start brushing their baby’s teeth as soon as the first tooth emerged, but 20% would first seek the counsel of a health professional, 13.9% were unsure, and 11.3% planned to do this when the baby started eating solids. Their findings highlighted that currently in the UK half of pregnant women are unaware of the correct brushing timing ^[39][81].

Oral health education is fundamental in preventing dental caries in children, with the goal of changing the knowledge, attitudes, and behaviors of the patient and the caregiver of the patient that put children at risk of oral illness; however, the child’s ability to assimilate and mimic the good as well as bad habits of adults cannot be ignored ^[40][8].

As outlined by Naidu et al. in 2020, also in settings characterized by positive attitudes toward preventive oral healthcare, a variable degree of uncertainty regarding dental attendance, supervised brushing, fluoride use, and sugar intake could be outlined. These findings suggest that these items require a special emphasis in oral health promotion programs targeted at improving early childhood oral health ^[41][82].

As outlined by the WHO, oral health education and community engagement are essential for preventing early childhood caries especially in a low to middle-income countries. The family represents the child’s primary source of learning about oral health and risk factors. The WHO suggests improvement in the awareness of oral health and ECC prevention among parents through proper health communication and the provision of sound information on disease prevention and treatment ^[42][83].

Evidence suggests the effectiveness of behavioral therapies against ECC when used at the individual and family levels ^[43][84]. The motivational interview is a promising approach to induce positive changes in caregivers’ oral health knowledge and child behavior outcomes. The results are improved when delivered in a patient-centered environment, rather than in the potentially stressful and distracting environment of a busy dental clinic ^[44][85].

In a recent report, Toniazzo et al., 2019, outlined how mobile applications and text messages can be a promising means to increase oral health awareness, of young children’s parents, and promote stable behavioral change ^[45][86].

A single, low-cost, low-intensity intervention could significantly reduce the risk of new caries: Pine et al., 2020, in fact, have shown how efficient dental nurse intervention could be, based on motivational interviewing and focused on prevention of future caries in children who have undergone primary tooth extraction. ^[46][87].