Loss of permanent teeth is an environmental factor that can lead to malocclusion by causing neighboring teeth to drift, tilt, or supra-erupt into the vacant space. This displacement disrupts the normal occlusal relationship and alignment of teeth, resulting in malocclusion. Unlike genetic causes, this is an acquired condition influenced by external factors such as trauma, caries, or periodontal disease leading to tooth loss. Proper management often involves timely replacement of missing teeth to maintain arch integrity and occlusion.

Reference: Wheeler's Dental Anatomy, Physiology and Occlusion, 10th Edition.