Final answer:
Overhangs on dental restorations can lead to chronic inflammatory periodontal disease by increasing plaque retention, which results in inflammation and more severe gum disease.
Step-by-step explanation:
Overhangs on restorations initiate chronic inflammatory periodontal disease primarily by increasing plaque retention. Plaque retention is the accumulation of bacterial biofilms on the teeth, which can lead to various oral health issues. When plaque accumulates, bacteria such as Porphyromonas, Streptococcus, and Actinomyces colonize the gingival space, leading to inflammation and gum damage known as gingivitis, which can further progress to periodontitis. It is crucial to maintain good oral hygiene to prevent such conditions, as periodontal disease can lead to more severe health complications, including tooth loss and the erosion of surrounding bone structure.