FREE DMD Biomedical and Dental Sciences Questions and Answers

Question 1

According to Socransky's microbial complexes, which group of bacteria, known as the 'Red Complex', is most strongly associated with the progression of chronic periodontitis and increased probing depths?

Accepted Answer

Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola

Answer

Streptococcus mutans, Streptococcus sobrinus, Lactobacillus acidophilus

Answer

Aggregatibacter actinomycetemcomitans, Capnocytophaga species, Eikenella corrodens

Answer

Actinomyces viscosus, Streptococcus sanguinis, Veillonella parvula

Question 2

A dentist administers a conventional inferior alveolar nerve block (IANB) for a procedure on a mandibular first molar. Despite achieving profound anesthesia of the lip and chin, the patient reports sharp pain when the tooth is touched. Which of the following is the most likely reason for this anesthesia failure?

Accepted Answer

Accessory sensory innervation was provided by the mylohyoid nerve.

Answer

The injection was administered too low, missing the mandibular foramen.

Answer

The long buccal nerve, which innervates the pulp, was not anesthetized.

Answer

The lingual nerve was inadvertently anesthetized instead of the inferior alveolar nerve.

Question 3

The development of a unilateral cleft lip is primarily caused by the failure of fusion between which two embryonic structures?

Accepted Answer

The maxillary process and the medial nasal process.

Answer

The two medial nasal processes in the midline.

Answer

The lateral nasal process and the maxillary process.

Answer

The right and left mandibular processes.

Question 4

A 10-year-old patient presents for an initial examination. Clinically, the teeth have a characteristic blue-gray opalescent hue. Radiographs reveal bulbous crowns with marked cervical constriction and near-complete obliteration of pulp chambers and root canals in both the primary and permanent dentitions. What is the most likely diagnosis?

Accepted Answer

Dentinogenesis Imperfecta

Answer

Amelogenesis Imperfecta

Answer

Regional Odontodysplasia

Answer

Tricho-Dento-Osseous Syndrome

Question 5

Which of the following best describes the primary post-eruptive mechanism by which topical fluoride inhibits the caries process?

Accepted Answer

It enhances remineralization by forming less acid-soluble fluorapatite.

Answer

It directly kills cariogenic bacteria like Streptococcus mutans.

Answer

It physically blocks the orifices of dentinal tubules.

Answer

It stimulates an increase in salivary buffering capacity.

Question 6

When taking a final impression for a multi-unit fixed partial denture, which property of an elastomeric impression material is most critical for ensuring the prosthesis will fit accurately?

Accepted Answer

Dimensional stability

Answer

Hydrophilicity

Answer

Tear strength

Answer

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