The process to integrate information and communication technologies (ICT), where teachers play a decisive role, is complex. The objective of this study is to build a basic model that connects teachers' ICT technological and pedagogical competences with the use of these technological resources by teachers (both personal-professional use and use with students). The model also considers how personal and contextual factors influence this relationship. A secondary analysis study was used, whose sample included 1095 male and female Primary, Secondary and Higher Education teachers from the Valencian Community (east Spain). Information was collected with a questionnaire from two survey design studies. Using an MIMIC model, teachers' integration of ICT was optimally modeled. This model shows a complex relation between competence and use. Technological competences influence pedagogical competences and personal-professional use, while pedagogical competences influence personal-professional use and use in class. Use in class is influenced by both pedagogical competences and personal-professional use. Personal and contextual factors influenced the four dimensions of use and competence. This basic model of the relationship between teachers' ICT competences and using these educational resources helps us to understand the complex process of integrating ICT into classrooms. Therefore, this model is a key element to guide teacher training in ICT.