Free AACD sample questions

Correct answer: Fabricating a removable acrylic splint at the proposed VDO for the patient to wear and evaluate.

Restoring a lost VDO is a complex process that requires careful verification. The most predictable and reversible method is to use a diagnostic tool like a removable acrylic splint or provisional restorations. This allows the patient to function at the new VDO for several weeks, enabling the clinician to assess phonetics (e.g., 'S' sounds), comfort of the masticatory muscles, and TMJ health. This trial period confirms the appropriateness of the new VDO before committing to definitive restorations. Relying solely on facial proportions, arbitrary measurements, or phonetics alone is not sufficient and can lead to failure.

Correct answer: False

While light/laser activation can accelerate the breakdown of hydrogen peroxide, numerous clinical studies have shown that it does not significantly improve the final whitening result or its stability over time compared to properly formulated, chemically-activated systems. The primary factors for success are the concentration of the whitening agent and the duration of contact with the tooth. The heat generated by lights can also increase the risk of tooth sensitivity and pulpal irritation.

Correct answers: Fabricating a silicone index from the wax-up and creating an in-mouth composite mock-up.; Evaluating phonetics, particularly the 'F' and 'V' sounds, with the mock-up in place.; Checking for interferences in protrusive and lateral excursive movements with the mock-up.

Correct answer: Surgical crown lengthening with osseous recontouring.

The diagnosis of altered passive eruption, confirmed by the apical position of the CEJ relative to the gingival margin with adequate bone support, indicates that excess soft and hard tissue is covering the anatomical crowns. The definitive treatment is surgical crown lengthening, which involves a gingivectomy to expose the CEJ and osseous recontouring to re-establish a proper biologic width (approximately 3mm from the proposed gingival margin to the alveolar crest). This procedure will expose the correct tooth proportions and reduce the gingival display. Orthodontic intrusion is for vertical maxillary excess, veneers would create overly long teeth, and Botox is a temporary solution for a hyperactive lip, not a tissue problem.

Correct answer: A positive nodule on the intaglio surface of the crown.

A rocking or fulcrum effect is most commonly caused by a single point of contact on the internal (intaglio) surface of the restoration that prevents it from seating fully and stably. This is often a small positive bleb or nodule resulting from a minor imperfection in the die or the milling process. Using a fit-checking material (e.g., silicone paste or occlusal spray) will quickly identify the precise location of the interference, which can then be carefully adjusted. An over-tapered prep would lead to poor retention but not necessarily a specific rock. Sintering distortion is possible but less common. A die spacer issue would typically cause a universally loose or tight fit.

Correct answer: 1.0 unit

The Golden Proportion (approximately 1.618:1) suggests that, when viewing the smile from the front, each tooth should be about 61.8% of the size of the tooth immediately mesial to it. If the central incisor (the larger element) is 1.618, the lateral incisor (the next element) would be 1.0. Following this, the visible portion of the canine would be approximately 0.618.

Correct answer: It minimizes the risk of post-operative sensitivity while maximizing the enamel bond.

The selective-etch (or selective enamel etch) technique combines the benefits of both self-etch and etch-and-rinse systems. By using the universal adhesive in self-etch mode on dentin, the smear layer is modified rather than completely removed, and the dentinal tubules are not exposed as aggressively, which significantly reduces the risk of post-operative sensitivity. Concurrently, selectively etching the enamel margins with phosphoric acid creates a deeper, more retentive etch pattern on the highly mineralized enamel, resulting in a stronger and more durable marginal seal. This hybrid approach optimizes the bond to both substrates.

Correct answer: Progressively increase in size and volume from the midline to the canines.

A youthful and natural smile displays a progressive increase in the size of the incisal embrasures moving distally from the midline. The embrasure between the central incisors is the smallest, the one between the central and lateral is larger, and the one between the lateral and canine is the largest. This graduation helps to delineate the individual teeth and avoid a monolithic, unnatural appearance.

Correct answer: Perform internal (walking) bleaching on tooth #9 prior to veneer preparation.

The most effective and conservative approach is to address the source of the discoloration first. By performing internal bleaching, the dark stump shade of tooth #9 can be lightened to match the adjacent teeth. This creates a uniform underlying color foundation, allowing for the use of the same high-translucency (HT) ceramic material across all veneers for a consistent and vital appearance. Relying solely on opaque cements or more opaque ceramics for just one tooth can lead to a devitalized, 'flat' look for tooth #9 that does not match the lifelike translucency of the other veneers.

Correct answer: HT blocks offer a more natural, chameleon effect, while LT blocks are better for masking discoloration.

The main difference between HT and LT lithium disilicate is the level of translucency. HT blocks are more translucent, allowing more light to pass through. This creates a chameleon effect, where the restoration picks up the color of the underlying tooth, resulting in a very natural and vital appearance, ideal for veneers on well-colored teeth. LT blocks are more opaque. While they appear less vital than HT restorations, their lower translucency is advantageous for masking moderately discolored underlying tooth structure or metal posts. Flexural strength and bonding properties are similar between the two.