We present in this position paper how we conducted a literature review on teacher digital maturity models. We extracted 11 models applicable to the field of compulsory schooling. Here, we propose a synthesis of the constituent dimensions of each model and how these dimensions contribute to determine the digital maturity levels of teachers. While our synthesis highlights the diversity of the dimensions included in the models, it also reveals that most of these models provide only a partial picture of technology maturity. Moreover, most of these models focus on the latest levels of maturity, associated with innovative or pioneering teachers, and leave out non-or low digital user teachers, who are well represented in the French context. In the last part of this position paper, we propose a unified model of teachers' digital maturity, called "MUME", addressing these two issues.