Dentosphere : World of Dentistry

# Which of the following cannot be used to block undercuts intraorally? A. Addition silicon B. Plaster of Paris C. Irreversible hydrocolloid D. Temporary restorative material # Inability of a material to sustain plastic deformation before the fracture occur: A. Toughness B. Hardness C. Brittleness D. Critical Stress   

  When 30-50% of the upper teeth protrude over the lower teeth, an overbite occurs. Many reasons contribute to overbite problems in children. In this article, let’s first understand the types of overbite problems that exist, what are their causes and how they can be treated.     Types of Overbites They are of two types: Vertical overbite: The top teeth significantly overlap the bottom teeth       Horizontal overbite: The top teeth protrude over the bottom teeth   Overbites are also categorized as dental or skeletal in nature.   ·          In dental overbites, the teeth cause the overbite to form. ·          In skeletal overbites, the jaw is responsible for the overbite to occur.   The overbite teeth problem is the most common type of bite problem and occurs due to a lot of reasons. Let us delve into some:   Causes of Ov...

# When using only standard floss, the mesial root surface of which of the following teeth is typically NOT totally cleaned? A. Mandibular central incisor B. Mandibular 1st premolar C. Mandibular 1st molar D. Maxillary 1st premolar E. Maxillary central incisor The correct answer is D. Maxillary first premolar. The mesial root surface of the maxillary 1st premolar is typically NOT thoroughly cleaned using ONLY dental floss due to the mesial root concavity. Because of the lack cleansibility of the mesial of this tooth, It is advised to use inter dental brushes, end tuft brushes, tooth pick in holders, rubber tips, and powered floss to clean these interproximal areas. This is because of the type of gingival embrasure space on the mesial aspect off maxillary 1st premolar. The three types of gingival embrasures are: Type I: Having NO inter dental papilla loss Type II: Partial loss of inter dental papilla Type lIl: Complete loss of inter dental papilla The mesial surface of the maxillary 1st ...

 # Which of the following is not found in acute necrotizing ulcerative gingivitis? A. Pocket formation B. Tooth loss C. Bone loss D. Gingival recession The correct answer is A. Pocket formation. NUG or NUP does not usually lead to periodontal pocket formation, because the necrotic changes involve the junctional epithelium, a viable junctional epithelium is needed for pocket deepening.