This document discusses impression trays and techniques for making custom impression trays. It explains that stock trays are pre-made but not always accurate, so custom trays made from materials like shellac, compound, or acrylic resin molded to a study cast are often needed. The document provides detailed instructions for making custom trays using different materials and techniques, including using wax spacers to provide room for impression material and ensuring tray borders extend to anatomical landmarks.
This document discusses the posterior palatal seal, which is the area of soft tissue along the junction of the hard and soft palates that can be compressed by a maxillary denture to aid in retention. It defines the posterior palatal seal and describes its functions, which include resisting forces on the denture and maintaining contact during function. The document outlines important anatomical structures like the vibrating lines and hamular notch that influence determination of the posterior palatal seal area. It also discusses techniques for locating and marking the seal, as well as factors that must be considered like a patient's soft palate classification.
Preeti Chaudhary acknowledges the staff of the Department of Prosthodontics for their support during clinical training. The document discusses the posterior palatal seal area of maxillary dentures. It defines the posterior palatal seal and describes its functions in retaining the denture and reducing gagging. Methods for marking the seal area include the conventional approach using a trial denture base, the fluid wax technique, and arbitrary scraping of the master cast. Errors in recording the seal area can lead to under or overextension of the denture border.
This document provides instructions for fabricating custom impression trays using either light cure resin or tray resin. It describes how to mark registration lines on casts, block out undercut areas, adapt the resin materials, and trim the trays. Completed trays should have rounded, smooth edges of proper thickness and extension, with finger rests and handles as needed.
This document discusses clinical and laboratory remounting in complete dentures. It begins by introducing complete dentures and the importance of proper occlusion. Errors can occur during the fabrication process that affect occlusion. Remounting procedures, including laboratory and clinical remounting, are recommended to identify and correct occlusal errors. Laboratory remounting involves using a split-cast mounting technique to remount the dentures on an articulator after processing. Clinical remounting takes new interocclusal records in the patient's mouth and mounts the dentures on an articulator to correct errors made during the initial records. Selective grinding is then used to refine the occlusion based on the remount records.
This document discusses factors affecting denture retention, including classification, interfacial forces, adhesion, cohesion, oral and facial musculature, atmospheric pressure, undercuts, parallel walls, and gravity. It defines retention as the resistance of a denture to forces that attempt to displace it from its basal seat. Primary retention comes from physical and mechanical means like surface area, adaptation, viscosity and secondary retention from surrounding musculature. Denture adhesives are discussed as a way to augment existing retention mechanisms by increasing adhesion, cohesion and viscosity between the denture and mucosa.
The document discusses various concepts related to complete denture impressions including definitions, techniques, materials and anatomical considerations. It defines key terms like preliminary impression, final impression, relief and supporting areas. It describes different impression techniques like mucocompressive, mucostatic and selective pressure. Factors affecting retention, stability and support of dentures are also summarized. The steps involved in making impressions are outlined which include examination, tray selection, border molding and the final impression.
impression techniques in Removable Partial Denture Dr.Richa Sahai
This document discusses impression procedures for removable partial dentures. It defines partial denture impressions and differentiates them from complete denture impressions. Various impression techniques are described including anatomic form impressions, functional impression techniques like McLean's method and the functional reline method. The document reviews literature on modified techniques like the altered cast technique and selective tissue placement impressions. It emphasizes the importance of functional impressions to distribute load and maximize longevity of remaining structures. In summary, the choice of impression technique impacts the support, function and longevity of the resulting removable partial denture.
This document discusses the posterior palatal seal, including its definition, function, anatomical considerations, techniques for recording it, and potential errors. The key points are:
1. The posterior palatal seal provides retention, stability, and prevention of air leakage for maxillary dentures.
2. It is located along the junction of the hard and soft palate and extends from the pterygoid hamulus on either side.
3. Special techniques like using indelible pencil and having the patient say "AH" are used to identify and record the seal area during impression making.
This document discusses the posterior palatal seal, which is the area of soft tissue along the junction of the hard and soft palates that can be compressed by a maxillary denture to aid in retention. It defines the posterior palatal seal and describes its functions, which include resisting forces on the denture and maintaining contact during function. The document outlines important anatomical structures like the vibrating lines and hamular notch that influence determination of the posterior palatal seal area. It also discusses techniques for locating and marking the seal, as well as factors that must be considered like a patient's soft palate classification.
Preeti Chaudhary acknowledges the staff of the Department of Prosthodontics for their support during clinical training. The document discusses the posterior palatal seal area of maxillary dentures. It defines the posterior palatal seal and describes its functions in retaining the denture and reducing gagging. Methods for marking the seal area include the conventional approach using a trial denture base, the fluid wax technique, and arbitrary scraping of the master cast. Errors in recording the seal area can lead to under or overextension of the denture border.
This document provides instructions for fabricating custom impression trays using either light cure resin or tray resin. It describes how to mark registration lines on casts, block out undercut areas, adapt the resin materials, and trim the trays. Completed trays should have rounded, smooth edges of proper thickness and extension, with finger rests and handles as needed.
This document discusses clinical and laboratory remounting in complete dentures. It begins by introducing complete dentures and the importance of proper occlusion. Errors can occur during the fabrication process that affect occlusion. Remounting procedures, including laboratory and clinical remounting, are recommended to identify and correct occlusal errors. Laboratory remounting involves using a split-cast mounting technique to remount the dentures on an articulator after processing. Clinical remounting takes new interocclusal records in the patient's mouth and mounts the dentures on an articulator to correct errors made during the initial records. Selective grinding is then used to refine the occlusion based on the remount records.
This document discusses factors affecting denture retention, including classification, interfacial forces, adhesion, cohesion, oral and facial musculature, atmospheric pressure, undercuts, parallel walls, and gravity. It defines retention as the resistance of a denture to forces that attempt to displace it from its basal seat. Primary retention comes from physical and mechanical means like surface area, adaptation, viscosity and secondary retention from surrounding musculature. Denture adhesives are discussed as a way to augment existing retention mechanisms by increasing adhesion, cohesion and viscosity between the denture and mucosa.
The document discusses various concepts related to complete denture impressions including definitions, techniques, materials and anatomical considerations. It defines key terms like preliminary impression, final impression, relief and supporting areas. It describes different impression techniques like mucocompressive, mucostatic and selective pressure. Factors affecting retention, stability and support of dentures are also summarized. The steps involved in making impressions are outlined which include examination, tray selection, border molding and the final impression.
impression techniques in Removable Partial Denture Dr.Richa Sahai
This document discusses impression procedures for removable partial dentures. It defines partial denture impressions and differentiates them from complete denture impressions. Various impression techniques are described including anatomic form impressions, functional impression techniques like McLean's method and the functional reline method. The document reviews literature on modified techniques like the altered cast technique and selective tissue placement impressions. It emphasizes the importance of functional impressions to distribute load and maximize longevity of remaining structures. In summary, the choice of impression technique impacts the support, function and longevity of the resulting removable partial denture.
This document discusses the posterior palatal seal, including its definition, function, anatomical considerations, techniques for recording it, and potential errors. The key points are:
1. The posterior palatal seal provides retention, stability, and prevention of air leakage for maxillary dentures.
2. It is located along the junction of the hard and soft palate and extends from the pterygoid hamulus on either side.
3. Special techniques like using indelible pencil and having the patient say "AH" are used to identify and record the seal area during impression making.
This document discusses different types of major connectors that can be used in removable partial dentures. It describes the definitions and requirements of major connectors. For maxillary major connectors, it covers palatal bar, palatal strap, double palatal bar, horseshoe connector, closed horseshoe, and complete palate. Selection criteria and advantages/disadvantages of each type are provided. For mandibular major connectors, it discusses lingual bar, sublingual bar, lingual plate, interrupted lingual plate, and their indications. The document aims to help in selecting the appropriate major connector based on a patient's clinical situation.
This document discusses factors affecting stability in complete dentures. It defines stability as the quality of a prosthesis to resist displacement from functional stresses. Key factors discussed include the relationship of the denture base to underlying tissues, the external surface and periphery to surrounding muscles, and the relationship of opposing occlusal surfaces. The document reviews literature on topics like retromylohyoid extension and its effect on stability. It also examines how factors like impression accuracy, border extension, ridge anatomy, arch form, occlusal scheme, and tooth position can impact stability.
12- Denture processing and laboratory errorsAmalKaddah1
The document discusses errors that can occur during the denture fabrication process, from initial impressions through final processing. It notes that errors may stem from clinical procedures, laboratory techniques, or material properties. Specific errors are described for impression taking, jaw relation records, tooth arrangement, processing techniques like flasking, packing, and curing, and final polishing. Attention to each step is important to avoid defects that can compromise the fit, function, or aesthetics of the final dentures.
The document discusses guidelines for selecting teeth for complete dentures. It describes various concepts for anterior tooth selection based on factors like size, form, shade, and composition. Size is determined by pre-extraction records or post-extraction measurements of facial features and the residual ridge. Form depends on the patient's facial profile, sex, age and personality. Shade selection considers the patient's age, complexion and desires. Both porcelain and acrylic materials are used. Guidelines are also provided for posterior tooth selection, focusing on shade, size, number, form and material composition suited for balancing occlusion and the patient's needs.
This document discusses the posterior palatal seal (PPS), including its role, location, and function in complete denture treatment. It defines the PPS and discusses factors that govern denture retention. The document covers PPS anatomy, design, clinical procedures, techniques for recording the PPS, and classifications of palatal forms and soft palate shapes. It provides details on locating the vibrating line and summarizes literature on determining the proper placement of the PPS.
This document provides instructions for constructing a special tray for making final impressions for complete dentures. It describes how to outline and fabricate rigid trays made of light-cured resin for the maxillary and mandibular arches using a preliminary cast. The trays are trimmed to be 2mm short of the vestibule with clearance for frenal attachments. Handles are added to the trays for positioning in the mouth during the impression. Wax spacers are then used on the casts under the trays to provide a uniform 3mm space for impression material.
This document defines key terminology used in maxillomandibular relations. It discusses the three types of maxillomandibular relations: orientation, vertical, and horizontal relations. Specific terms are defined, such as centric relation and eccentric relation. Vertical dimension is explained, including vertical dimension at rest, at occlusion, and freeway space. The document also covers topics like occlusal plane, Camper's plane, Christensen's phenomenon, and closest speaking space.
This document provides instructions for making final impressions for complete dentures, including custom tray fabrication, border molding techniques, and using selective pressure to record tissues in an undisplaced position. It describes areas that require special attention for the maxillary and mandibular impressions, such as the posterior palatal seal and retromylohyoid space. The goal is to make impressions that provide maximum coverage, close adaptation, and proper support and retention for the dentures.
11.complete denture wax‐up and flasking procedureshammasm
This document discusses the process of waxing up dentures and flasking them for acrylic resin processing. It describes criteria for waxing the upper and lower dentures, including contouring the wax base and arranging the teeth. The flasking process involves investing the wax dentures and casts in dental stone in a flask, followed by wax elimination and packing of the flask with acrylic resin. The flask then undergoes polymerization cycling by heating in a water bath to cure the resin into the final denture bases.
Occlusion in complete denture must be developed to function efficiently and with the least amount of trauma to the supporting tissues. this ppt content Difference between artificial and natural dentition
Requirements of complete denture occlusion
Occlusal schemes for complete denture
Axioms for balance occlusion
Theories of occlusion
Concepts of occlusion
balance occlusion
Non-balance occlusion
Conclusion
covers overall every topic of occlusion in complete denture
The dentist has significant influence over the appearance of a patient's lower face when providing complete dentures. Several anatomical landmarks of the face are important reference points for establishing occlusal planes and positioning teeth, such as the interpupillary line and Camper's plane. Incorrect positioning of teeth or denture bases can distort normal facial features like the mentolabial sulcus and philtrum. Maintaining the proper vertical dimension and anterior tooth positioning is crucial for restoring facial aesthetics in edentulous patients.
This document discusses different types of connectors used in fixed partial dentures (FPDs). It describes rigid connectors that do not allow movement, including cast, soldered, loop, and rigidly-joined multi-unit FPD connectors. It also describes non-rigid connectors that allow limited movement, such as tenon-mortise, split pontic, and cross-pin/wing connectors, which are indicated for situations requiring some flexibility like pier abutments. Special considerations for pier abutments, cantilever FPDs, and replacing canines are also covered.
SELECTION AND ARRANGEMENT OF ARTIFICIAL TEETHShankar Hemam
This document discusses the selection and arrangement of artificial teeth for complete denture prostheses. It covers factors to consider for anterior tooth selection such as shade, size, and form. Shade is determined by age, sex, complexion and patient preference. Size is selected based on methods using pre-extraction guides, anthropological measurements, theoretical concepts, and anatomical landmarks. Form is based on the patient's face shape, profile, and concepts of dentogenics and dynesthetics which aim to create natural-looking teeth. The document also discusses posterior tooth selection and common errors in tooth arrangement.
1. Stability in complete dentures is influenced by factors like residual ridge anatomy, quality of soft tissues, impression quality, occlusal planes, tooth arrangement, and contour of the polished surface.
2. Various muscles like the buccinator, orbicularis oris, and mentalis can impact denture stability if the denture borders and contours do not allow for proper function.
3. Establishing balanced occlusion is important for stability, as imbalanced forces can displace the denture during jaw movement.
Anatomical Landmarks for Complete DenturesAhmed Samy
This document describes important anatomical landmarks for extraoral and intraoral examination in complete denture fabrication. Extraoral landmarks include the nasolabial sulcus, mentolabial sulcus, and angle of the mouth. Intraoral maxillary landmarks are the alveolar ridge, palate, tuberosities, and fovea palatinae. Intraoral mandibular landmarks include the alveolar ridge, retromolar pad, mental foramen, and mylohyoid ridge. The document outlines the primary and secondary stress bearing areas, relief areas, and border structures to consider for complete denture impressions and prosthesis design.
The document discusses posterior palatal seals (post dams) used in denture fabrication. It describes:
1) The ideal placement of the posterior palatal seal on the non-movable soft palate tissue just behind the hard palate.
2) Techniques for forming the seal during impression-making like using low-fusing compound or scraping the master cast.
3) The functions of the posterior palatal seal in improving denture retention, preventing food from getting under the denture, and diminishing irritation.
This document discusses post-insertion complaints with complete dentures. It begins by classifying common and uncommon complaints, such as sore spots, loose fit, speech issues, and more. It then discusses the management of these complaints, including examining denture faults, occlusal discrepancies, retention issues, and other potential causes. The document provides an overview of evaluating and addressing patients' post-insertion complaints to improve the function and comfort of their complete dentures.
Steps of Fabrication of Removable Partial DentureRida Tariq
The document outlines the steps involved in fabricating a removable partial denture, which includes both clinical and laboratory steps. The clinical steps include diagnosis, treatment planning, impressions, framework try-in, and denture insertion. The laboratory steps involve model preparation, surveying, framework fabrication, waxing, flasking, curing, and finishing. Key steps include diagnostic impressions to create study models, designing the prosthesis framework, final impressions, packing denture base material into the mold, curing, and inserting the final denture.
1. Classification of jaw relations establishes orientation, vertical, and horizontal relations between the jaws. Orientation defines cranial references, vertical defines jaw separation, and horizontal defines front-back and side-to-side jaw positions.
2. Centric relation is a repeatable reference position important for recording jaw relations and developing occlusion. It is the starting point for mandibular movements and where opposing teeth contact without proprioceptive guidance.
3. Methods for recording centric relation include interocclusal records, graphic tracings, and functional methods to position the mandible at the correct vertical dimension. The record must be made with equal pressure and avoid distortion until casts are mounted.
This document discusses the arrangement of posterior teeth in complete dentures. It begins by outlining the individual positioning of maxillary and mandibular premolars and molars, noting things like their orientation relative to the occlusal plane. The maxillary first molar is described as the "key tooth" in occlusion. The document then compares natural dentition occlusion to complete denture occlusion and lists goals for establishing balanced articulation in dentures. Factors like condylar guidance, incisal guidance, and compensating curves are introduced as important considerations for achieving balanced occlusion.
The document discusses impression trays, which are used to carry and control impression material in the mouth. It describes different types of trays, including stock trays, custom trays, and special trays. Special trays are custom-made for each patient based on a preliminary cast and are used to make final impressions. The document outlines the procedure for fabricating a special tray using materials like shellac, acrylic resin, and wax spacers. Special trays provide accurate impressions and are more comfortable for patients compared to stock trays.
This document discusses the process of making custom trays and master casts for complete dentures. It involves making a custom tray using materials like acrylic resin or light-cured resin to take final impressions. Border molding is then done to shape the impression material borders. Final impressions are poured in stone to make master casts, which are trimmed and indexed for remounting in the lab to fabricate dentures.
This document discusses different types of major connectors that can be used in removable partial dentures. It describes the definitions and requirements of major connectors. For maxillary major connectors, it covers palatal bar, palatal strap, double palatal bar, horseshoe connector, closed horseshoe, and complete palate. Selection criteria and advantages/disadvantages of each type are provided. For mandibular major connectors, it discusses lingual bar, sublingual bar, lingual plate, interrupted lingual plate, and their indications. The document aims to help in selecting the appropriate major connector based on a patient's clinical situation.
This document discusses factors affecting stability in complete dentures. It defines stability as the quality of a prosthesis to resist displacement from functional stresses. Key factors discussed include the relationship of the denture base to underlying tissues, the external surface and periphery to surrounding muscles, and the relationship of opposing occlusal surfaces. The document reviews literature on topics like retromylohyoid extension and its effect on stability. It also examines how factors like impression accuracy, border extension, ridge anatomy, arch form, occlusal scheme, and tooth position can impact stability.
12- Denture processing and laboratory errorsAmalKaddah1
The document discusses errors that can occur during the denture fabrication process, from initial impressions through final processing. It notes that errors may stem from clinical procedures, laboratory techniques, or material properties. Specific errors are described for impression taking, jaw relation records, tooth arrangement, processing techniques like flasking, packing, and curing, and final polishing. Attention to each step is important to avoid defects that can compromise the fit, function, or aesthetics of the final dentures.
The document discusses guidelines for selecting teeth for complete dentures. It describes various concepts for anterior tooth selection based on factors like size, form, shade, and composition. Size is determined by pre-extraction records or post-extraction measurements of facial features and the residual ridge. Form depends on the patient's facial profile, sex, age and personality. Shade selection considers the patient's age, complexion and desires. Both porcelain and acrylic materials are used. Guidelines are also provided for posterior tooth selection, focusing on shade, size, number, form and material composition suited for balancing occlusion and the patient's needs.
This document discusses the posterior palatal seal (PPS), including its role, location, and function in complete denture treatment. It defines the PPS and discusses factors that govern denture retention. The document covers PPS anatomy, design, clinical procedures, techniques for recording the PPS, and classifications of palatal forms and soft palate shapes. It provides details on locating the vibrating line and summarizes literature on determining the proper placement of the PPS.
This document provides instructions for constructing a special tray for making final impressions for complete dentures. It describes how to outline and fabricate rigid trays made of light-cured resin for the maxillary and mandibular arches using a preliminary cast. The trays are trimmed to be 2mm short of the vestibule with clearance for frenal attachments. Handles are added to the trays for positioning in the mouth during the impression. Wax spacers are then used on the casts under the trays to provide a uniform 3mm space for impression material.
This document defines key terminology used in maxillomandibular relations. It discusses the three types of maxillomandibular relations: orientation, vertical, and horizontal relations. Specific terms are defined, such as centric relation and eccentric relation. Vertical dimension is explained, including vertical dimension at rest, at occlusion, and freeway space. The document also covers topics like occlusal plane, Camper's plane, Christensen's phenomenon, and closest speaking space.
This document provides instructions for making final impressions for complete dentures, including custom tray fabrication, border molding techniques, and using selective pressure to record tissues in an undisplaced position. It describes areas that require special attention for the maxillary and mandibular impressions, such as the posterior palatal seal and retromylohyoid space. The goal is to make impressions that provide maximum coverage, close adaptation, and proper support and retention for the dentures.
11.complete denture wax‐up and flasking procedureshammasm
This document discusses the process of waxing up dentures and flasking them for acrylic resin processing. It describes criteria for waxing the upper and lower dentures, including contouring the wax base and arranging the teeth. The flasking process involves investing the wax dentures and casts in dental stone in a flask, followed by wax elimination and packing of the flask with acrylic resin. The flask then undergoes polymerization cycling by heating in a water bath to cure the resin into the final denture bases.
Occlusion in complete denture must be developed to function efficiently and with the least amount of trauma to the supporting tissues. this ppt content Difference between artificial and natural dentition
Requirements of complete denture occlusion
Occlusal schemes for complete denture
Axioms for balance occlusion
Theories of occlusion
Concepts of occlusion
balance occlusion
Non-balance occlusion
Conclusion
covers overall every topic of occlusion in complete denture
The dentist has significant influence over the appearance of a patient's lower face when providing complete dentures. Several anatomical landmarks of the face are important reference points for establishing occlusal planes and positioning teeth, such as the interpupillary line and Camper's plane. Incorrect positioning of teeth or denture bases can distort normal facial features like the mentolabial sulcus and philtrum. Maintaining the proper vertical dimension and anterior tooth positioning is crucial for restoring facial aesthetics in edentulous patients.
This document discusses different types of connectors used in fixed partial dentures (FPDs). It describes rigid connectors that do not allow movement, including cast, soldered, loop, and rigidly-joined multi-unit FPD connectors. It also describes non-rigid connectors that allow limited movement, such as tenon-mortise, split pontic, and cross-pin/wing connectors, which are indicated for situations requiring some flexibility like pier abutments. Special considerations for pier abutments, cantilever FPDs, and replacing canines are also covered.
SELECTION AND ARRANGEMENT OF ARTIFICIAL TEETHShankar Hemam
This document discusses the selection and arrangement of artificial teeth for complete denture prostheses. It covers factors to consider for anterior tooth selection such as shade, size, and form. Shade is determined by age, sex, complexion and patient preference. Size is selected based on methods using pre-extraction guides, anthropological measurements, theoretical concepts, and anatomical landmarks. Form is based on the patient's face shape, profile, and concepts of dentogenics and dynesthetics which aim to create natural-looking teeth. The document also discusses posterior tooth selection and common errors in tooth arrangement.
1. Stability in complete dentures is influenced by factors like residual ridge anatomy, quality of soft tissues, impression quality, occlusal planes, tooth arrangement, and contour of the polished surface.
2. Various muscles like the buccinator, orbicularis oris, and mentalis can impact denture stability if the denture borders and contours do not allow for proper function.
3. Establishing balanced occlusion is important for stability, as imbalanced forces can displace the denture during jaw movement.
Anatomical Landmarks for Complete DenturesAhmed Samy
This document describes important anatomical landmarks for extraoral and intraoral examination in complete denture fabrication. Extraoral landmarks include the nasolabial sulcus, mentolabial sulcus, and angle of the mouth. Intraoral maxillary landmarks are the alveolar ridge, palate, tuberosities, and fovea palatinae. Intraoral mandibular landmarks include the alveolar ridge, retromolar pad, mental foramen, and mylohyoid ridge. The document outlines the primary and secondary stress bearing areas, relief areas, and border structures to consider for complete denture impressions and prosthesis design.
The document discusses posterior palatal seals (post dams) used in denture fabrication. It describes:
1) The ideal placement of the posterior palatal seal on the non-movable soft palate tissue just behind the hard palate.
2) Techniques for forming the seal during impression-making like using low-fusing compound or scraping the master cast.
3) The functions of the posterior palatal seal in improving denture retention, preventing food from getting under the denture, and diminishing irritation.
This document discusses post-insertion complaints with complete dentures. It begins by classifying common and uncommon complaints, such as sore spots, loose fit, speech issues, and more. It then discusses the management of these complaints, including examining denture faults, occlusal discrepancies, retention issues, and other potential causes. The document provides an overview of evaluating and addressing patients' post-insertion complaints to improve the function and comfort of their complete dentures.
Steps of Fabrication of Removable Partial DentureRida Tariq
The document outlines the steps involved in fabricating a removable partial denture, which includes both clinical and laboratory steps. The clinical steps include diagnosis, treatment planning, impressions, framework try-in, and denture insertion. The laboratory steps involve model preparation, surveying, framework fabrication, waxing, flasking, curing, and finishing. Key steps include diagnostic impressions to create study models, designing the prosthesis framework, final impressions, packing denture base material into the mold, curing, and inserting the final denture.
1. Classification of jaw relations establishes orientation, vertical, and horizontal relations between the jaws. Orientation defines cranial references, vertical defines jaw separation, and horizontal defines front-back and side-to-side jaw positions.
2. Centric relation is a repeatable reference position important for recording jaw relations and developing occlusion. It is the starting point for mandibular movements and where opposing teeth contact without proprioceptive guidance.
3. Methods for recording centric relation include interocclusal records, graphic tracings, and functional methods to position the mandible at the correct vertical dimension. The record must be made with equal pressure and avoid distortion until casts are mounted.
This document discusses the arrangement of posterior teeth in complete dentures. It begins by outlining the individual positioning of maxillary and mandibular premolars and molars, noting things like their orientation relative to the occlusal plane. The maxillary first molar is described as the "key tooth" in occlusion. The document then compares natural dentition occlusion to complete denture occlusion and lists goals for establishing balanced articulation in dentures. Factors like condylar guidance, incisal guidance, and compensating curves are introduced as important considerations for achieving balanced occlusion.
The document discusses impression trays, which are used to carry and control impression material in the mouth. It describes different types of trays, including stock trays, custom trays, and special trays. Special trays are custom-made for each patient based on a preliminary cast and are used to make final impressions. The document outlines the procedure for fabricating a special tray using materials like shellac, acrylic resin, and wax spacers. Special trays provide accurate impressions and are more comfortable for patients compared to stock trays.
This document discusses the process of making custom trays and master casts for complete dentures. It involves making a custom tray using materials like acrylic resin or light-cured resin to take final impressions. Border molding is then done to shape the impression material borders. Final impressions are poured in stone to make master casts, which are trimmed and indexed for remounting in the lab to fabricate dentures.
The document discusses the process of making custom trays and master casts for complete dentures, including taking final impressions, border molding, and boxing and pouring the impressions to create the definitive master casts. Key steps include fabricating a custom tray, border molding with low-fusing compound or impression material, taking final impressions with materials like zinc oxide eugenol or elastomers, and boxing and pouring the impressions in dental stone to create the finished master casts.
The document discusses different types of impression trays used in dentistry. It defines impression trays as devices that carry, confine and control impression material in the mouth. The key types discussed are stock trays, which are pre-made and reusable, and custom trays, which are fabricated for a specific patient based on a preliminary cast. Stock trays come in various sizes and materials, while custom trays provide a better fit and less impression material is needed. The document provides details on selecting and fabricating different types of impression trays.
An introductory and simple guide assembled by dental students and reviewed by Dr. Hasannin Al-Namel. our seminar about impression trays used in prosthodontics
This document provides information about making impressions for complete dentures. It discusses the objectives and requirements of an ideal impression, including maximum extension without muscle impingement and intimate contact with covered tissue areas. It describes primary, secondary/final, and corrective impressions. The types of impression materials and trays are outlined, including stock trays, special/individual trays, and techniques like border molding and boxing. The document also summarizes different techniques for making final impressions, such as minimal pressure, mucocompressive, and selective pressure techniques.
Impression philosophies for completely edentulous patientsAmalKaddah1
The document discusses impression philosophies for fully edentulous patients. It covers the objectives, principles, and requirements of impression making including preservation of tissues, retention, esthetics, stability, and support. It describes the steps in making impressions including primary impressions, diagnostic casts, custom trays, and final impressions. Various impression materials and techniques are discussed such as minimal pressure, selective pressure, and functional mandibular impressions. Custom tray fabrication using wax spacers, acrylic resin, and border molding is also outlined.
This document provides instructions for making custom trays and record bases for edentulous patients. It describes how to make custom trays by outlining the borders, blocking undercuts, adapting acrylic resin, and finishing. Record bases are made by blocking undercuts, applying vaseline, adapting resin sheets, and trimming. Occlusion rims are fabricated by adapting wax to the record bases to approximate the shape and position of natural teeth, with dimensions provided. The document gives details on techniques, materials, and quality checks for custom trays and record bases.
A custom made device prepared for a particular patient which is used to confine and control an impression material making an impression.
It makes on the cast obtained from primary impression.
It is used for making final impression.
Edentulous ridge shows variations in shape and size.
It shows the type of impression technique
1, Selective pressure technique
2, Minimal pressure technique
This document describes the process of making a special tray for complete dentures. It begins by defining an impression tray and describing the types, which are stock trays and custom/special trays. Special trays are fabricated on a patient's cast, making them a better fit than stock trays. The document then covers the advantages of special trays, materials used to make them, ideal requirements, and the step-by-step process to fabricate a special tray, including identifying the peripheral extension, model preparation, adapting spacer wax, applying a separating medium, constructing the tray base, and adding a handle.
This document provides an overview of complete dentures and removable partial dentures. It discusses the clinical and laboratory steps involved, including preliminary impressions, final impressions using specialized trays, and jaw relation records. Techniques for fabricating special trays and occlusal rims are described. The document also covers arranging artificial teeth on the dentures, including guidelines for positioning individual teeth, and mounting the dentures on an articulator. Common materials used for various stages are listed.
This document discusses the process of fabricating custom trays for dental impressions. It begins by defining a custom tray and listing criteria for their construction. There are two main methods described - constructing a resin tray using a finger adaptation or sprinkle-on technique, or a shellac tray. For resin trays, the process involves outlining features on the preliminary cast like sulci and borders, adapting a wax spacer, and then applying resin to the cast. For shellac trays, a preformed base is softened and adapted to the cast, with borders rolled and excess trimmed. The document compares advantages of resin versus shellac trays.
This document provides instructions for making final impressions for complete dentures. It discusses:
- The objectives of final impressions including preservation of tissue and bone, support, stability, and retention
- Techniques such as selective pressure that record tissues at rest to avoid displacement
- Procedures for border molding custom trays and developing an accurate peripheral seal
- Taking final impressions with light-body material to achieve a mucostatic impression
This document provides instructions for making final impressions for complete dentures. It discusses:
- The objectives of final impressions including preservation of tissue and bone, support, stability, and retention.
- Techniques for recording tissues at rest to avoid displacement and damage, including selective pressure and border molding.
- Steps for making custom trays including design, tray materials, and border molding sequences.
- Considerations for final maxillary impressions including mobile tissues, tori, and seal areas.
- Selection and application of impression materials to achieve an accurate final impression.
This document provides information on final impressions. It defines a final impression as one made for the purpose of fabricating a prosthesis after initial registration. It discusses different types of impressions based on purpose and technique. The objectives of making an accurate impression are also outlined. The document then describes the process of making a final impression using custom trays, stock trays, or record bases. Details are provided on border molding, tray preparation, material selection, and making impressions for both maxillary and mandibular arches. Digital impression systems are also briefly discussed.
secondary impression / final impression in complete denture.
#prosthodontics
#prostho
BDS 4th year
Nischala Chaulagain
Nobel Medical College , Biratnagar
A temporary denture base is used to support artificial teeth during procedures like determining jaw relations and tooth arrangement. It aims to resemble the final denture. Common materials used are auto-polymerizing resins, heat cure resin, thermoplastics, and shellac. Self-cure acrylic resin is a popular option that can be manipulated using techniques like the sprinkle technique, finger-adapted dough technique, or stone mould dough technique to adapt to the cast. The temporary denture base should adequately support teeth, adapt to tissues, and be stable, rigid, and non-reactive in the mouth.
A number of theories have been put forward for impressions. each having its own advantage and disadvantage.
Different spacers guide and aid in in making the desired impression with adequate pressure in the desired region of the arch in maxilla and mandible. different materials are used for spacers depending on the need.
This document provides instructions for making final impressions for complete dentures. It discusses the objectives of impressions which are preservation of tissue, support, stability, esthetics and retention. The techniques described are aimed at recording tissues in their resting position to avoid displacement. Border molding is used to establish contours and test peripheral seal. A selective pressure technique uses light material to achieve a mucostatic impression. Proper tray design and customization are emphasized.
The final impression techniques aim to accurately record the supporting structures to construct a removable partial denture (RPD) that maximally distributes forces. There are two main techniques - the anatomic form impression records tissues at rest using stock or custom trays with alginate or rubber base. The physiologic form impression records tissues under load using selective pressure techniques. Key objectives are maximum ridge coverage, distributing forces over large areas, and relating supporting structures under function. Custom trays are made with wax spacers and stops to provide uniform impression material thickness. Impressions are inspected before pouring with stone plaster to produce a master cast for RPD framework construction.
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2. Impression
Impression : is an imprint or negative reproduction of the
entire denture bearing area and border seal area.
This recording is usually fulfilled by:
1(Primary or preliminary impression:
Is negative registration of the denture bearing tissues and the
related oral structures required to produce a primary
(study) cast. It is made in ready-made stock trays.
2(Final impression:
Is negative registration of the denture bearing tissues and the
related oral structures required to produce a master cast. It
is made in special trays constructed on the study cast,
hence more accurate and suitable for each case.
3. Impression trays
Impression tray:
is an instrument used for carrying the impression material in
to the mouth for maintaining it in position during setting or
hardening and supporting it during removal from the
mouth and when pouring the model.
The impression trays consist of a floor and flanges.
The difference between the upper and lower tray is that the
upper has a palatal portion while the lower has lingual
flanges
4. Requirement of impression tray
1-They should be strong and rigid, and can be sterilizer and
polish
2-They should be clean and smooth.
3-They should allow for equal thickness of impression
material over the entire fitting surface.
4-The flanges of the tray must reach the functional
position of the sulci and frena and yet not displace them.
5-The tray should hold the impression material in correct
position in the mouth and consequently must cover the
whole areas of the jaw, which are required for the
impression .They must prevent distortion of the material
during setting and removal from the mouth
5. Stock tray
1-Stock trays are ready made trays.
2-Supplied in various shapes and sizes.
3-Trays are usually made from nickel silver, tin,
stainless steel, aluminum or plastics
4-in edentulous cases:
A- Stock trays having round floor.
B- Short flange
C- The handles staggered (inclined) as to clear
the lip and avoid its distortion
6. 5-in dentulous cases:
A-stock trays having flat floor
B-vertical high flanges
C-the handles can be made straight by extending it
straight across the floor of the trays
6-in partially edentulous cases:
Tray with combined round and flat floor.
7-If it is too large it will distort the tissue around the
borders of the impression and will pull the soft
tissues under the impression away from the bone
8-If it is small, the border tissue will collapse inward on to
the residual ridge (this will reduce the support for the
denture and prevent the proper support of the lips by the
denture flange.
10. Special (individual) tray
"Custom tray"
To produce accurate impression and avoid variation
in transmitted pressure there must be an equal
thickness of impression material over the entire
surface; also the flanges of the tray must reach the
functional position of the sulci and frena and yet
not displace them. It is unusual for a stock tray to
full these requirements, and therefore, special tray
should be construction for each patient.
Before making a special tray, the best impression
possible with a stock tray is made, and model
(cast) is made for this impression.
11. The special tray materials vary according to
the type of impression technique selected,
the more common being:
A-non metallic (plastic) individual tray:
1-shellac base plate
2-compound impression
3-acrylic resin (most commonly used(
4-old dentures.
B- Metallic special tray
12. A- Non metallic (plastic) individual
tray
1-Shellac base plate:
These materials are normally used when the
impression is to be made of plaster of Paris or
alginate impression materials.
To provide space in the tray for the impression
material, the model must be covered with two
layers of wax and the tray adapted to this surface.
This layer of wax is called shim or spacer. This
shim can also be made of shellac. It can also be
produced by immersing the model in the water for
10 minutes then dipping it in molten wax.
13.
14. Three dips are usually enough to produce the shim. The tray should be
perforated if alginate impression is used. A special tray with stops may
be preferred for mucostatic impression. These stops can be made by
perforating the shim.
Four stops, two in the lateral incisor areas and two in the molar regions
are usually made. These stops should touch the oral mucosa during
impression making and should be lightly scraped lateral before
pouring the cast.
When the shim is used it should be dusted over with talcum powder to
prevent the tray material from sticking to it. The shellac base plate
material is softened uniformly by passing it to and for over a flam and
then adapted to the shim. If necessary, resoft to complete the process.
Trim the edges with a sharp knife or scissors and smoothen with a file
and sandpaper, leaving a rounded periphery to the tray. If alginate
impression material is to be used, the tray should be perforated over its
entire surface by drilling holes of approximately one sixteenth of an
inch diameter space about one quarter to three eight of an inch apart. A
handle of any desired shape can be made of shellac base plate or iron
wire.
15. 2-Compound impression
Sometimes compound impression are used as
special tray after scraping 2-3 mm. from the
fitting surface of the impression to provide
space for the plaster impression( plaster
wash impression) . Perforation are required
if alginate is used for making the
impression.
16.
17. 3-Acrylic resin
Certain impression techniques call for the use of a
close fitting tray (when zinc oxide and eugenol
past is used, the shim is not required and the tray
is directly adapted to the model) in particular zinc
oxide eugenol pastes for edentulous cases. This
type of tray can be made in either heat curing or
autocuring acrylic resin. If undercuts are present
on the cast, they should be blocked out with
plaster and separating medium is then applied to
the cast.
18. A wax base of the required thickness is made on the cast and the edges
are seated down. The wax base is flasked in the same manner as
recommended for a complete denture. After separation of the flask, the
wax is boiled out, the flask is cooled, the cast is coated with a suitable
separating medium and packing is carried out in the usual manner.
Deflasking, finishing and polishing is carried out as described for
complete denture process.
A quicker method of making an acrylic resin tray is by the use of
autopolymerizing acrylic resin material.
Undercuts are blocked out with plaster or wax.
After covering the model with a separating medium, the powder and
liquid of the acrylic resin should be mixed together according to the
manufacture's instruction.
When the material is dough stage in consistency it is rolled flat to an even
thickness and spread rapidly over the cast, using the fingers to adapt.
Polymerization will take place in a few minutes at room temperature
and if required can be accelerated further by placing the cast in warm
water. When the heat or cold curing acrylic resin is hard, the periphery
is trimmed with a stone or bur and the tray is ready for use in final
impression making.
19. Advantages of the acrylic impression
trays
1-easier to make
2-rigid
3-light in weight
4-can be easily cut down, if over sized.
20. Constructing the auto polymerizing
acrylic resin impression tray having
a spacer
On the cast obtained from the preliminary
impression the periphery can be outlined
with a disposable indelible marker wax
spacer is placed with in the outlined border
to provide space in the individual
impression tray for the final impression
material.
21. The posterior palatal seal area on the cast is not covered with
the wax spacer. Thus the completed final impression tray
will contact the upper residual ridge across the posterior
palatal seal. Base plate wax approximately 1mm thick is
placed on the cast as designated by the previously drawn
outline. A self curing acrylic resin tray material mixed and
uniformly adapted over the cast so the tray will be 2-3mm
thick. A resin handle is attached in the anterior of the tray
to facilitate removable of the final impression. The handle
is placed in the position of the upper anterior teeth so it
will not distort the upper lip when the tray is in the mouth.
The acrylic resin tray is removed from the preliminary
cast; the labial and buccal flanges of the impression tray
are marked and reduced until they are about 2mm shorter
than the reflections.
22.
23.
24.
25. Spacer constructing the lower final
impression tray having
The cast is outlined for a wax spacer, which
will provide space in the individual tray for
the final impression material. a wax spacer
about 1mm thick is placed over the crest
and slopes of the residual ridge.
The buccal shelf on each side and the
retromylohyoid spaces on the cast are left
uncovered.
26. .Thus the completed final impression tray will contact the
mucosa in the region of the buccal shelves to place
additional pressure in this primary-stress bearing area
when the final impression is made. Extra wax can be
placed over the lingual slopes of the cast to provide
additional space for the action mylohyoid muscles when
the final impression is made self-curing (cold curing or
auto polymerizing) acrylic resin tray material is mixed and
uniformly distributed over the cast so the final impression
tray will be approximately 2-3mm. thick. An anterior resin
handle is centered over the labial flange. The flange of the
tray should be contoured. The buccal, labial and lingual
flanges of tray are reduced until the borders are short of
the limiting anatomic structures.
27. 4-Old dentures as a final impression
tray
The existing denture may be used as a special
tray as in case of making zinc oxide eugenol
impression for relining of the dentures.
28. B – Metallic special trays
This type can be used for any impression materials,
but it is required only when compound is to be
used. Although swaging nickel silver between dies
and counter die can make metal trays, casting is
the method generally used. The material for
casting tray is alloy of tin two parts, lead one part,
or tin alone. The production of metallic special
tray is time consuming and expensive for this
reason it is not normally used.
30. 1-Hard areas
A-owing to the varying thickness of the
mucosa membrane on which the denture
rests it is frequently necessary to relieve the
denture over areas of thin mucosa in order
to avoid pain or rocking of the denture and
the commonest position requiring such
relief is the midline raphe of the hard palate.
31. B- All areas to be relieved should be
determined by careful palpation and their
outlined shown on the model used for
constructing the special tray. The depth of
relief's dependent on the compressibility of
the areas of thick mucosa membrane and
should be sufficient to prevent the denture
from pressing on the areas of thin mucosal
coverage when full masticatory loads are
imposed.
32. C- Relief areas on dentures should always
merge in to the surrounding fitting surface
and should never have aclearly defined
outline. The median palatine raphe and the
torus palatinus and torus mandibularis are
examples of the hard areas that need relief.
33. Methods of relief
1-Automatic relief:
This type of relief can be obtained by using muco-
compressing (mucofunctional) impression
technique.
2-Direct relief:
a- a plaster impression may be scraped to added of
1mm or less depending on the effect desired, over
area corresponding to the hard parts in the mouth.
This method is not applicable to hydrocolloids or
zinc oxide and eugenol, or rubber base past
impression materials.
34. b- Another method, witch can produce the
same effect but more conveniently and
accurately, is by attaching one ore more
layers of tin foil to the cast. An outline of
the area to be covered should be marked by
pencil on the cast. Foil of 0.05-inch
thickness is then cut into shape and
burnished by a blunt instrument into close
contact and cemented to the cast before the
trial denture is made.
35. 2-Sensitive area
Relief of pressure over certain structures is required
because they are sensitive to pressure.
a- incisive papilla in the anterior part of the hard
palate.
b- The rugae are usually rough, resistant to friction
and insensitive, yet they sometimes become
flattened and deformed by pressure of an
unrelieved.
36. c- Over prominent tuberosities or bony
nodules in any location especially if they
are covered with a thin tightly stretched
mucosa membrane.
d- Mental foramen in the premolar region of
the mandible.
e-over the crest of thin lower ridge
f- Sharp mylohyoid ridge.
37. Shape of the relief
1-Upper cast: the relief area will normally be
pear-shaped with the broadest part
anteriorly; it should not encroach on the
crest of the ridge except the incisive papilla.
2-Lower cast: rarely requires relief; but foil
may be necessary over the areas that need
relief.