# Conscious Inhalation Sedation with Nitrous Oxide and Oxygen in Children: A Retrospective Study
###### Abstract  
Dental anxiety is a common problem in younger children, especially those who have had traumatic or perceived traumatic dental treatments. Nitrous oxide (N\({}_{2}\)O) and oxygen (O\({}_{2}\)) have been recommended by the American Academy of Pediatric Dentistry as the optimal approach for uncooperative or anxious patients. The study aimed to evaluate the cooperation of children treated on deciduous teeth without local anesthesia and with rubber dam. A retrospective study was conducted from January 2019 to December 2020 in a private dental practice on children aged 4-10 years who had previously reported cases of dental anxiety during dental procedures or refused to undergo them. After an initial cognitive examination, the children underwent conservative treatment lasting a maximum of 30 min. Initially, 100% O\({}_{2}\) was administered, then N\({}_{2}\)O dose was gradually increased to 35%. At the end of the treatment, 100% pure O\({}_{2}\) was administered for 5 min. Children's cooperation was assessed by Venham score before treatment (T0), at the end of induction (T1), and during the treatment (T2). A total of 371 children (age: 6.3 \(\pm\) 1.7 years) were included in the study. Cooperation increased significantly from baseline at T1 (_p_ < 0.001) and T2 (_p_ < 0.001). Younger children (4-6 years) showed lower levels of cooperation at baseline (_p_ < 0.001) but achieved optimal levels of cooperation at T1 (_p_ = 0.022). Only 2.7% of children reported side effects. N\({}_{2}\)O/O\({}_{2}\) proved to be an effective and safe method in achieving a good level of cooperation in younger children. Keywords:nitrous oxide; dental anxiety; dental fear; children; Venham score +
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rather than interventional factors [12] in which parental attitudes and perceptions toward dental treatment play a crucial role [13; 14]. In 2012, [PERSON] et al., who studied 608 mother-child dyads, reported a significant association between maternal dental anxiety and the incidence of untreated dental caries in children [13]. Similar trends were also demonstrated by [PERSON] et al. (2019), who showed that the children whose mothers were \"extremely anxious\" (phobic) had the highest average number of decayed, missing, or filled teeth [14]. In younger children (24-36 months) with adolescent mothers, the presence of maternal anxiety disorders, such as agoraphobia and social phobia, was significantly associated with children's dental anxiety [15]. In children, early acquisition of dental anxiety is strongly related to negative experiences as well as to personality and certain beliefs regarding medical professionals [16]. However, the negative value attributed to the dental experience does not seem to be related to objective evaluations such as the invasiveness of the procedure or the number of dental procedures but rather to a subjective evaluation in which children and their parents view dental treatment as a negative experience [17]. Inadequate or perceived inadequate previous dental treatment leads to increasing dental anxiety [18], creating a vicious cycle in which OHRQoL is severely compromised. Overall, children with behavioral disorders are twice as likely as children without behavioral disorders to have dental caries at age 5 [19], are less likely to have dental radiographs taken, are more likely to have restorative treatments performed without local anesthesia [20], and are more likely to have teeth extracted [21]. The treatment procedure is not only a tremendous source of stress for patients but also a time-consuming and stressful activity for dentists, who are often reluctant to provide dental care to anxiety patients because they do not know how to properly manage children's anxiety [22].