Talk to us?
👤 Welcome User
prosthodontics - 3 Questions
When drilling cylindrical implant sites in bone, the following is false: only speeds above 20,000 rpm should be used in drilling.
The most reproducible relation of the jaws that is used in fixed denture construction is Centric Relation (CR). Here's a detailed explanation of the options provided and why Centric Relation is the correct answer: 1) Centric Occlusion (CO): This is the position of the mandible where the incisor and posterior teeth of the maxilla and mandible are in maximum intercuspation, meaning the teeth are in their most closed and stable contact. It is the position that occurs when the condyles are in the most superior and anterior position in the glenoid fossae of the temporal bones. While important for the function of the teeth, centric occlusion is not always a reliable reference for the construction of a fixed denture, as it can be influenced by various factors such as tooth wear, pathology, or parafunctional habits. Moreover, it is a dynamic relationship that can change over time. 2) Centric Relation (CR): Centric relation is the most retruded, unstrained position of the mandible on the maxilla from which the mandible can move to the lateral and protrusive positions. It is the basis for the articulators in dentistry and is considered the most reproducible jaw relationship for the fabrication of fixed dentures. CR is determined by the temporomandibular joint (TMJ) and does not involve tooth contact. This is crucial because it provides a consistent and predictable starting point for constructing a denture that will function harmoniously with the TMJ and the surrounding soft tissues. It is the position where the condyles are in a centric relation with the fossa and the disk is properly situated, which minimizes strain and maximizes stability during function. 3) Protrusive Contact Position: This is the position of the mandible where the incisor or canine teeth make contact with the maxilla in a forward and downward movement. While it is a functional movement of the jaw, it is not a stable or reproducible position for the construction of fixed dentures because it is highly dependent on the muscles and may not be consistent across different individuals or even during different occasions for the same individual. 4) Lateral Contact Position: This refers to the position of the mandible during lateral movements, where the teeth contact the maxilla on the side of the arch. Similar to protrusive contact, it is a functional position that is influenced by muscle activity and not a stable reference for denture construction. Lateral movements are also not the primary focus in fixed denture construction, which is mainly concerned with the vertical and anteroposterior relationships of the jaws.
The primary stress-bearing area in the mandibular edentulous ridge is the buccal shelf.
MCQ