Dentosphere : World of Dentistry

  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.

 # Which of the following describes the etiology of cone-cutting? A. Inadequate exposure time B. Excessive mA C. Excessive kVp D. Incorrect source-object distance E. Incorrect placement of X-ray machine The correct answer is E. Incorrect placement of X Ray machine. Cone-cutting occurs when the X-ray machine is not lined up properly with the X-ray sensor or film. The film or sensor should be placed perpendicular to the X-ray collimator to ensure that all of the necessary information is picked up. External devices are often used to ensure that the film/sensor are perpendicular to the X-ray collimator.

  # A periapical radiograph suggests an opaque mass Over the apex of the maxillary right 2nd molar. A second periapical radiograph is made with the X-ray head adjusted in a more mesial direction. The second periapical suggests that the object in question has moved distally compared to the 1st radiograph. Which of the following directions describes the location of the object? A.In-between the roots B. Buccal to the tooth C. Lingual to the tooth D. Not enough information is provided The correct answer is B. Buccal to the tooth. The SLOB (Same Lingual, Opposite Buccal) rule suggests that the object is buccal to the tooth. Because the object moved opposite to the positioning of the X-ray device for the 2nd radiograph it demonstrates buccal positioning If the object moved mesially with the head of the X-ray head being moved mesially, it would have demonstrated lingual/palatal positioning.

 # A person wearing complete denture has difficulty in pronouncing T. The reason may be: A. Too thick palatal area B. Incorrect position of upper incisor teeth C. Too thick mandibular bone D. Reduced salivary flow The correct answer is B. Incorrect position of upper incisor teeth.  - Sounds like t, d, n, etc. are alveolar sounds. These sounds are produced with tip of tongue touching anterior palate. - If maxillary anterior teeth are placed too far anteriorly, 'd' will sound like 't'. - If they are placed too palatally, 't' will sound like 'd'. 

 # Lentulo spirals are used for: A. Locating canal orifice B. Pulp extirpation C. Enlarging coronal third of the root canal D. Application of root canal sealer The correct answer is D. Application of root canal sealer.  - Finger pluggers are used for vertical compaction of gutta percha.  - Finger spreaders are used for  lateral compaction of gutta percha. - Lentulo spiral is used to deliver sealer or triple antibiotic paste to the root canal.