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Figure 2. Types of fracture. (A) Type 1, Fractures involving a small portion of the coronal tooth structure; (B) Type 2, fractures involving a small portion of the coronal tooth structure and cohesive failure of the restoration; (C) Type 3, fractures involving the tooth structure, cohesive and/or adhesive failure of the restoration, and root involvement that can be restored in association with periodontal surgery; and (D) Type 4, severe root and crown fracture, necessitating extraction of the tooth.