Which condition contributes to the development of midline diastema?

The development of midline diastema, which is a space between the two front teeth (maxillary central incisors), can be significantly influenced by the presence of missing teeth. When a permanent tooth is absent, it can disrupt the normal alignment and spacing of teeth, leading to gaps. This situation can cause adjacent teeth to shift over time, creating or exacerbating the diastema at the midline.

In the context of the other options, mandibular crowding generally leads to teeth being pushed closer together rather than creating gaps, making this less likely to contribute to a midline diastema. Proclination of incisors can also contribute to spacing issues, but it usually enhances the alignment of teeth rather than creating a space, particularly in the midline. An increase in pocket depth often relates to gum disease and periodontal issues, which contribute to tooth mobility rather than forming a diastema directly. Hence, the condition that most directly contributes to midline diastema is the missing of teeth.