1. Conclution More mesially inclined maxillary molars are likely to be associated with third molar eruption.

2. G. japonicum similar to the former, but deep purple in colour, stipe laterally or mesially located.

3. Objective: To measure changes in angular position and eruption status of mesially impacted mandibular third molars (M3) during 3-year follow-up period.

4. Conclusion This reflects that the second molars could move mesially during treatment in the second premolars extraction subjects, which can lead to the increase of the retromolar space.

5. Objective To assess the treatment method and outcome of mesially or horizontally impacted mandibular molars.

6. The third premolar and the first molar of miniature pigs inclinate mesially, and are similar with the first premolar and the first molar of the human beings.