1.55-year-old female, with 4578 missing teeth in the upper left and 5678 missing teeth in the upper right. All the remaining teeth in the mouth are healthy. Normal relationship. Kennedy classification: ()
A. Category I, subcategory I
B. Category II, Category I
C. the first subclass of the third category
D. Category IV, Category I
E. Category I and II
2.46-year-old female, the left lower 67 was missing, the left lower 8 did not erupt, and the remaining teeth in her mouth were healthy. Normal relationship. The correct design of pre-fixed denture restoration is: ()
A. The lower left 45 is used as the abutment of single-ended fixed denture.
B. The left lower abutment of 345 was repaired with single-ended fixed denture.
C. The left lower 2345 was used as abutment for single-ended fixed denture restoration.
D, left lower 5 as abutment for single-ended fixed denture restoration.
E. it is not suitable for single-ended fixed denture restoration.
3. One patient has a missing lower right 5, a healthy lower right 46 and a normal gap. The fulcrum line of removable partial denture can be designed as: ()
A. Diagonal type
B. Linear type
C. Horizontal line type
D. Vertical line type
E. plane type
A 4.58-year-old female, 876 in the lower right and 34 in the lower left, had her teeth extracted for more than 3 months due to periodontal pain. The lower right was loose at 5 Ⅰ ~ Ⅱ degrees without undercut, and the remaining teeth were normal. When repairing removable partial denture, the right retainer should be: ()
A. combined snap ring
B. Half snap ring
C. Extended snap ring
D.RPI clasp
E.RPA snap ring
A 5.54-year-old female patient, with unilateral mandibular free end missing, wore removable partial denture for 2 years, and the lingual plastic base was broken. It was found that the free end of the denture was inclined and the other parts were closed. The most appropriate treatment measures are: ()
A. re-bonding the damaged part of the substrate
B, relining the tissue surface of the free-end substrate.
C, bonding the broken part of the substrate again, and lining the tissue surface of the free end substrate again.
D, re-bonding the damaged part of the base to reduce the diameter of the free-end denture,
E. Re-repair of mandibular partial denture
6. Periodontal epithelial barrier, the most important thing is: ()
A. Oral gingival epithelium
B. sulcus epithelium
C. Binding epithelium
D. Residual enamel epithelium
E. gingival epithelium
Reference answer and analysis
1. Reference answer A. Analysis:
Thinking: This question examines Kennedy Classification, and candidates need to know the principles of determining and supplementing the main classification of each Kennedy Classification.
Complete analysis: the posterior teeth on both sides of the first kind of dental arch are missing, the distal end is free, and there are no natural teeth. The second kind of dental arch is missing teeth on one side, with a free end at the distal end and no natural teeth. One side of the third arch is missing, and there are natural teeth at both ends of the gap. The incisors of the fourth dental arch are continuously missing and cross the midline, and the natural teeth are far away from the gap. The fourth category is single gap, without subclasses, and the other three categories are classified according to the number of preserved gaps except the main gap. That is, except the main notch, one notch is the first subclass, two notches are the second subclass, and so on. If there are missing teeth before and after, the last gap is taken as the benchmark. If the posterior teeth on both sides of the dental arch are missing, and one side is missing teeth at the distal free end and the other side is missing teeth at the non-free end, the missing teeth at the free end are included in the second category, and the number of missing teeth is different according to subcategories. The most distal tooth of dental arch (such as the third molar or the second molar) is missing but not repaired, which is not classified. Therefore, choose a.
2. Reference answer E. Analysis:
Thinking: This topic examines the design of fixed denture. How to strictly grasp the indications of different tooth loss situations requires students to master them carefully.
Complete analysis: Single-ended fixed bridge is also called cantilever fixed bridge. A single-ended fixed bridge has only one end with a retainer and an abutment, and the bridge and the retainer are connected through a fixed connector, and the other end is a completely free cantilever without abutment support. Single-ended fixed bridge can be used for maxillary lateral incisor loss. Without maxillary canines, lateral incisors and first premolars are often used as abutments to make double-ended fixed bridges. The second and third molars are missing, or the periodontal area of the first and second molars that need compensation is too large, so it is not suitable to choose a single-ended fixed bridge. Generally, partial removable dentures or implant restorations are selected. The choice of fixed bridge for septal defect should depend on the location and number of specific edentulous areas, so the topic is E.
3. Reference answer D. Analysis:
Thinking: To examine the Cummer classification method of removable partial dentures, we need to master the determination of Cummer classification fulcrum line.
Complete analysis: Cummer classification is divided into four categories according to the position relationship between the direct retainer (mainly fulcrum bracket) of removable partial denture and dental arch. The connecting line of the retainer is called fulcrum line or loop line (supporting line), the lower right 5 is missing, the lower right 46 is healthy and the gap is normal. Therefore, the fulcrum line of removable partial denture can be designed as a vertical line, so choose D.
4. Reference answer C. Analysis:
Idea: This title is easy to make mistakes, and it is easy to choose option A by mistake. It belongs to the blind spot of knowledge points, so we should pay attention to the examination of questions.
Complete analysis: the right lower 876 is missing, because the abutment right lower 5 has ⅰ ~ ⅱ degree looseness, there is no available undercut, and the crown shape is poor. It is suitable to extend the clasp, and extend the retaining arm of the clasp from the notch to the incisor of the second tooth to obtain the function of retention and splint. The buccal-lingual arm on the first abutment and the opposite arm on the second abutment next to the gap do not enter the inverted concave area, but will generate a large torque on the abutment, and the retention arm is easy to deform, so it is not widely used in clinic, so C is selected.
5. Reference answer C. Analysis:
Thinking: This topic investigates the possible problems and solutions after the restoration of removable partial dentures, which are easy to be confused here. Attention should be paid to finding the reasons according to the stem tips, and then choose the appropriate treatment method.
Complete analysis: After wearing denture for a period of time, due to the absorption of alveolar bone, the tissue surface of denture base is not close to mucosal tissue, food is embedded, denture base is inclined, occlusion is unbalanced, and even denture base is broken. In addition, for dentures with missing free ends, because the impression is usually pressureless and the tissue surface of the base is slightly pressed, it should be re-lined, so C is selected.
6. Reference answer C. Analysis:
Thinking: This question examines the epithelial barrier of periodontal tissue, and the examination point is relatively biased, so you need to pay attention when reviewing.
Complete analysis: Gingival epithelium is a specific stratified squamous epithelium, which can be further divided into oral epithelium, gingival sulcus epithelium and combined epithelium. These small ecological areas covered by epithelium are often invaded by microorganisms in health and disease States. Therefore, gingival epithelium plays a very important role in controlling microbial infection, protecting subepithelial tissue and maintaining periodontal tissue homeostasis. The gingival tissue at the junction of gums and teeth is connected with the surface of teeth through the combined epithelium, which is called epithelial attachment. It closes the junction of soft and hard tissues and is an important barrier to resist microbial invasion. The renewal of combined epithelium is about 5 days, which is about twice as fast as that of gingival surface epithelium (A, B, D, E errors).