NEET MDS Shorts
602628
Conservative Dentistryovertrituration (i.e., triturating for longer than the recommended time) results in a mix that is warm and has a dull surface; often the mix sticks to the capsule; it shortens setting time (because the amalgam mass becomes heated), increases contraction, and increases creep; also increases tensile and compressive strength values (for lathe-cut alloys), decreases tensile and compressive strengths (for spherical alloys); overtrituration by 10% is acceptable
785586
Conservative DentistryExplanation: The external shape of a Class V amalgam
restoration is closely related to the contour of the marginal gingiva. This is
important for aesthetic and functional reasons, as the restoration must blend
seamlessly with the surrounding gingival tissue. The outline form should respect
the natural contours to minimize plaque accumulation and promote periodontal
health. While axial line angles and the direction of enamel rods are relevant to
the preparation, they do not primarily dictate the external shape of the
restoration.
402381
Conservative DentistryIn class V preparation, the pulpal wall is not present at all, as the cavity is
confined to the cervical third of the tooth. It does not extend into the pulp
chamber.
744262
Conservative DentistryExplanation: When dealing with adjacent Class III cavities, it is generally recommended to prepare the larger cavity first and fill it last. This approach allows the dentist to have better access and visibility when preparing the larger cavity, which can be more complex. Filling the larger cavity last helps to avoid contamination and ensures that the smaller cavity can be filled with precision without compromising the integrity of the larger restoration.
112856
Conservative DentistryRoughening the old restoration and re-etching it allows for better bonding of the new composite material.
986817
Conservative DentistryIn Class V restorations, which are located at the gingival third of the facial or lingual surfaces of teeth, the occlusal wall is typically wider than the gingival wall. This design helps in providing retention and resistance to the restoration, as the occlusal wall is more subject to occlusal forces.
887800
Conservative DentistryThe discoloration of amalgam restorations is often due to the formation of silver sulfide on the surface, which can occur due to the reaction of silver with sulfur compounds in the oral environment. The gamma I phase is a strong component of amalgam, while the gamma II phase is weaker and less stable. Oxides can form as well, but sulfides are more directly associated with the discoloration observed in clinical settings.
939848
Conservative DentistryDuring cavity preparation, the most common area for exposure is a Class V cavity in the first premolar. A Class V cavity is a five-sided cavity that involves the gingival margin of the tooth and the proximal surface. These cavities are particularly prone to exposure because the gingival tissue in this region can be thin, and the proximity to the bone can lead to inadvertent damage during the preparation process.