Radiographs have been used to aid dentists in detecting the presence of cavities in the deciduous teeth of children. This procedure is globally recommended because the conventional clinical examination usually overlooks some cavities. However, the real benefit of performing dental radiographs for this purpose is still unclear. Besides the hazards of ionizing radiation, the radiographs could provoke overtreatment of the children; hence, dentists would tend to restore more teeth than would be really necessary. Nowadays, it is preferable to overlook some cavities than treat the teeth unnecessarily. Therefore, the investigators aimed to perform this study to compare two different strategies for detecting cavities in deciduous teeth of children: one based on clinical examination performed alone and other using radiographs adjunct to the clinical examination. To compare these strategies, the investigators will consider outcomes related to children's health and welfare.

Despite most clinical guidelines throughout the world indicate that the clinicians take two bitewings for detecting caries lesions in primary molars of asymptomatic children, the evidence for this recommendation is based in cross-sectional studies performed in laboratorial setting or using convenience samples. The benefits and impact of performing radiographs on diagnosis and treatment decision of caries lesions in primary teeth, considering relevant outcomes for the patients, have not been evaluated yet. Thus, the aim of this study will be to evaluate the impact of performing radiographic examination for detecting caries lesions in primary teeth compared with the visual inspection performed alone, considering different outcomes related to the validity and children's health and welfare. For this, three different studies will be carried out according the following specific aims: (1) to evaluate the validity of radiographic examination adjunct to the visual inspection in detecting proximal caries lesions in primary molars in children with low and high caries experience through a cross-sectional design; (2) to evaluate the impact of radiographic examination adjunct to the visual inspection on the diagnostic and treatment decision of caries lesions in primary teeth in a before and after study; and (3) to evaluate the impact of radiographic examination adjunct to the visual inspection for detecting caries lesions in primary teeth on operative needs in the follow-ups and impact of oral health on the quality of life through a randomized clinical trial. To reach these objectives, 250 children aged 3 to 6 years who looked for dental treatment in our dental school will be randomly allocated in two groups according to the diagnostic strategy used for caries detection: visual inspection performed alone (control group) or visual inspection associated to radiographic examination (experimental group). After elaboration of treatment decision plan for two examiners, the children will be treated and followed-up for 2 years, with evaluations after 12 and 24 months after the ingress of the children in the study. The primary outcome will be the number of dental surfaces with dental treatment need in the follow-up, considering the aim (3). Then, children allocated in the control group will be reevaluated using radiographic examination, and the performance of two strategies for detecting proximal caries lesions will be evaluated, using temporary separation with orthodontic rubbers for one week as reference standard method. Moreover, a new treatment plan will be performed and compared with the treatment plan based on visual inspection alone. These two parts of the research will be carried out to reach the aims (1) and (2), respectively. Our working hypothesis is that the radiographic examination would actually exert little influence on outcomes related to the validity and children's health and welfare, and that visual inspection would be enough as diagnostic strategy for caries detection in primary teeth.

Inclusion Criteria:

• Children who sought dental treatment in our dental school (School of Dentistry, University of Sao Paulo, Sao Paulo, Brazil)
• Children aged 3 to 6 years
• Children with al least one primary molar in the mouth.

Exclusion Criteria:

• Children whose parents refuse to participate of the research
• Children presenting behavior problems during the treatment.