DDS Trivia 4 — Questions and Answers
Question 1: Which Angle's classification describes a malocclusion where the mesiobuccal cusp of the upper first molar occludes anterior to the buccal groove of the lower first molar?
- Class I
- Class II (Correct answer)
- Class III
- Class IV
Correct answer: Class II
Angle Class II malocclusion is defined by a distal relationship of the mandible, where the maxillary first molar is ahead (mesial) of its ideal position relative to the mandibular first molar.
Question 2: Which tooth structure is formed last during tooth development?
- Enamel
- Dentin
- Cementum (Correct answer)
- Pulp
Correct answer: Cementum
Cementum is deposited by cementoblasts after root formation begins, which occurs after enamel and dentin have already been laid down by ameloblasts and odontoblasts.
Question 3: What does the acronym 'BRONJ' refer to in dental practice?
- Bone Resorption of Normal Jaw
- Bisphosphonate-Related Osteonecrosis of the Jaw (Correct answer)
- Bilateral Recurrent Oral Necrotic Junction
- Buccal Recessive Oral Nerve Junction
Correct answer: Bisphosphonate-Related Osteonecrosis of the Jaw
BRONJ (now termed MRONJ—Medication-Related Osteonecrosis of the Jaw) is exposed necrotic bone in patients taking bisphosphonates or antiresorptive agents.
Question 4: Which primary (deciduous) teeth are the last to erupt in the oral cavity?
- Maxillary central incisors
- Mandibular lateral incisors
- Maxillary second molars (Correct answer)
- Mandibular canines
Correct answer: Maxillary second molars
The maxillary second primary molars are typically the last deciduous teeth to erupt, around 24–33 months of age, completing the primary dentition of 20 teeth.
Question 5: What is the scientific name of the primary pathogen responsible for early childhood caries (ECC)?
- Streptococcus salivarius
- Streptococcus mutans (Correct answer)
- Lactobacillus acidophilus
- Actinomyces viscosus
Correct answer: Streptococcus mutans
Streptococcus mutans is the principal bacterium responsible for early childhood caries due to its ability to produce lactic acid and adhere to tooth surfaces via glucans.
Question 6: Which anatomical landmark on the hard palate is used as a reference point in prosthodontic impressions?
- Incisive papilla
- Pterygomaxillary notch
- Fovea palatinae (Correct answer)
- Hamular notch
Correct answer: Fovea palatinae
The fovea palatinae are two small pits at the junction of the hard and soft palate and serve as a reliable landmark for establishing the posterior border of a complete maxillary denture.
Question 7: Which dental material contains bisphenol A-glycidyl methacrylate (Bis-GMA) as its primary resin matrix?
- Zinc phosphate cement
- Composite resin (Correct answer)
- Glass ionomer cement
- Zinc oxide eugenol cement
Correct answer: Composite resin
Composite resin restorative materials are based on Bis-GMA (bisphenol A-glycidyl methacrylate) monomer cross-linked with TEGDMA, providing tooth-colored esthetic restorations.
DDS Trivia 4
Which Angle's classification describes a malocclusion where the mesiobuccal cusp of the upper first molar occludes anterior to the buccal groove of the lower first molar?