Should a suitor annul his engagement to a girl after discovering that her upper teeth are artificial, knowing that she is not veiled but he sees the possibility of convincing her to wear the hijab after marriage, or should the marriage proceed and he continue his patience with her?

The purpose of marriage (نكاح) is to achieve affection (mawaddah) and mercy (rahmah) between the spouses. If there is a repulsive defect (عيب منفر) that prevents the realization of this purpose, then the husband has the right to annul the contract. Since an engagement (khitbah) is a promise to marry and not a contract, it is even more appropriate for him to have the right to annul it if the defect prevents the achievement of affection and mercy. However, if the defect is not repulsive and does not hinder the purpose of marriage, it is preferable to complete the marriage, especially if she is of good character and hopes to adhere to the law of Allah.