TOPIC: MOUTH PREPARATION IN RPD
🎯 KEY POINTS :
🔹Shape of the rest seat in natural posterior teeth should be saucer-shaped.
🔹A rest helps to transmit the occlusal stresses parallel to the long axis of the tooth.
🔹The intentional conservative tooth reduction to prepare guiding planes is called enameloplasty
🔍 DEFINITION :
🔺ENAMELOPLASTY: The intentional alteration of the occlusal surface of the teeth to change their form. (GPT 8th Ed)
🔷 Mouth Preparation Is Often Accomplished By Two Phases:
🔸Preprosthetic Phase
🔸Prosthetic Phase
📌 PRE-PROSTHETIC PHASE OF MOUTH PREPARATION INCLUDES THE FOLLOWING STAGES:
(i) Relief of pain and any infection
(ii) Oral surgical procedures
(iii) Conditioning of abused tissues
(iv) Periodontal therapy
(v) Occlusal plane correction
(vi) Orthodontic correction for misalignment
(vii) Splinting of weakened teeth for better support
🔷 Methods To Correct Uneven Occlusal Planes
🔸Enameloplasty
🔸Onlay
🔸Crown
🔸Endodontically treated tooth with a coping
🔸Extraction
🔸Surgical Repositioning
🔶 Correction Of Misalignment
💡Following are the methods used to correct misalignment:
- Orthodontic repositioning
- Enameloplasty
- Crowns
🔶 Provision Of Support To Weakened Teeth
💡Following methods are used :
- Removable splinting
- Fixed splinting
- Overdenture abutments
📌 PROSTHETIC PHASE OF MOUTH PREPARATION INCLUDES THE FOLLOWING STAGES:
(i) Preparation of the guiding planes
(ii) Preparation of the rest seat
(iii) Creation of retentive undercuts
(iv) Modification of height of contour
(v) Inlays, onlays and crowns
✳️ GUIDING PLANE: Vertically parallel surfaces on the abutment teeth or/and dental implant abutments oriented so as to contribute to the direction of the path of placement and removal of the removable dental prosthesis. (GPT 8th Ed)
🔷 Types Of Guiding Planes On The Basis Of Their Location
(i) Guiding planes on the abutment in tooth-supported cases
(ii) Guiding planes on the abutment next to the distal extension edentulous space
(iii) Guiding planes on the lingual surfaces of the abutment teeth
(iv) Guiding planes on the anterior abutment teeth