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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Ugly duckling stage affects
assistant
The correct answer is  The Broadbent's Phenomenon - Ugly Duckling Stage (8-11 years)
Around the age of 8 years, a midline diastema is commonly seen in the upper arch, which is usually misinterpreted by the parents as a malocclusion. Crowns of canines in young jaws impinge on developing lateral incisor roots, thus driving the roots medially and causing the crowns to flare laterally. The roots of the central incisors are also forced together, thus causing a maxillary midline diastema. The period from the eruption of lateral incisor to canine is termed as the Ugly Duckling stage. It is an unaesthetic metamorphosis, which eventually leads to an aesthetic result. With eruption of canines, the impingement from the roots shifts incisally, thus driving the incisor crowns medially, resulting in closure of the diastema.
Textbook of Orthodontics, Gurkeerat Singh, 2nd Ed, pg-46