The document discusses the altered-cast technique for fabricating removable partial dentures (RPDs). Key points include:
- The altered-cast technique involves making an impression of the residual ridges in their functional position after fitting the RPD framework, then separating the edentulous portion of the master cast to reposition it based on the new impression.
- This technique aims to improve the fit of the RPD base to the residual ridges and reduce stress on abutment teeth.
- The procedure involves border molding a custom tray attached to the fitted framework, then making an impression using elastic materials like polysulfide.
- In the lab, the edentulous portion of the master cast is
The human mandible can be related to the maxilla in several positions in the horizontal plane. Among these centric relation is a significant position, because of its usefulness in relating the dentulous and edentulous mandible to maxilla, where the teeth , muscles and temporomandibular joint function in harmony. It is a position of occluso-articular harmony.
The patient who requires a single denture opposing a natural or restored dentition challenges the clinician even more than the completely edentulous patient does. This is due to the biomechanical differences in the supporting tissues of the opposing arches. So a proper evaluation, correction of the existing factors and proper sequence of denture construction is necessary to give a more stable prosthesis.
When treating a patient with a removable partial denture, the natural and artificial teeth, both functionally and esthetically, must co-exist in a harmonious relationship.
Occlusal harmony between a removable partial denture and the remaining natural teeth is a major factor in preservation of the surrounding structures.
In removable partial dentures, because of the attachment of the denture to abutment teeth, occlusal stresses can be transmitted directly to the abutment teeth and other supporting structures, which results in sustained stresses that may be more damaging than those transient stresses found in complete dentures.
The human mandible can be related to the maxilla in several positions in the horizontal plane. Among these centric relation is a significant position, because of its usefulness in relating the dentulous and edentulous mandible to maxilla, where the teeth , muscles and temporomandibular joint function in harmony. It is a position of occluso-articular harmony.
The patient who requires a single denture opposing a natural or restored dentition challenges the clinician even more than the completely edentulous patient does. This is due to the biomechanical differences in the supporting tissues of the opposing arches. So a proper evaluation, correction of the existing factors and proper sequence of denture construction is necessary to give a more stable prosthesis.
When treating a patient with a removable partial denture, the natural and artificial teeth, both functionally and esthetically, must co-exist in a harmonious relationship.
Occlusal harmony between a removable partial denture and the remaining natural teeth is a major factor in preservation of the surrounding structures.
In removable partial dentures, because of the attachment of the denture to abutment teeth, occlusal stresses can be transmitted directly to the abutment teeth and other supporting structures, which results in sustained stresses that may be more damaging than those transient stresses found in complete dentures.
Impression for distal extension bases /certified fixed orthodontic courses b...Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
00919248678078
Impression for distal extension bases /certified fixed orthodontic courses b...Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
00919248678078
13- Relining, rebasing and repair of removable dentures.pptxAmalKaddah1
COMPLETE DENTURE CONSTRUCTION
1- Diagnosis and Treatment Planning for Removable Prosthodontics
2- Preliminary Maxillary and mandibular impression procedures
3- Final Maxillary and mandibular impression procedures
4- Jaw Relation Registration
a. Introduction and the stomatognathic system
What 'occlusion' is and why it is important
b. Definitions.
c. Check denture foundation and Establishment of facial contour.
d. Establishment of the occlusal plane.
e. Importance of mounting the maxillary cast using Maxillary face-bow record and transfer.
f. Determination of vertical dimension of centric occluding relation.
g. Determination of centric and eccentric relations at the accepted vertical dimension.
5- Selection of Artificial Teeth
6- Prosthetic Problems and possible solutions in Setting –up of teeth for skeletal Class I, II and Class III arch relationship of completely edentulous patients.
7- Try-in of the wax trial complete denture.
8- Complete denture insertion (Delivery)
9- Occlusal corrections.
10- Managements of Post Insertion Problems and Complaints.
11- Single denture and Kelly's Syndrome
12- Denture Processing and Laboratory Errors.
13- Relining, rebasing and repair of removable dentures
Retrievel of denture, correction of occlusal descripencies/certified fixed o...Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
Retrievel of denture, correction of occlusal descripencies,/dental crown &bri...Indian dental academy
Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.
Fabrication of Complete Dentures for A Patient with Resorbed Mandibular Anter...QUESTJOURNAL
ABSTRACT: The loose and unstable lower complete denture is one of the most common problems faced by denture patients with highly resorbed ridge. The management of such highly resorbed ridges has always posed a difficulty to the prosthodontist.Obtaining consistent mandibular denture stability has longbeen a challenge for dental profession. The simplest approach often is to extend the denture base adequately for proper use of all available tisues.To achieve this goal impression of the resorbed mandibular ridge is very important. The objective is to develop a physiologic impression with maximum support of both hard and soft tissues.In such cases, an innovative technique of impressionmaking by using a close fitting tray and anelastomeric impression material tomake a proper impression to achieve maximum retentionand stability.This article describes an impression technique used for highly resorbed mandibular ridge using an all green impression technique, to gain maximum retention andstability
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
There are a number of conditions that present acutely, predominantly with pain and/or swelling
A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Ve...kevinkariuki227
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
2. introduction
It was originally described more than 80 years ago.
It was developed to improve the residual ridge to dentition relationship of
the prosthesis.
This technique has the potential benefits of reducing the number of
postoperative visits, preserving the residual ridges, improving stress
distribution, decreasing food impaction and decreasing the torqueing of
abutment teeth.
3. What is successful RPD (Steffel)
Cross-stability of the framework.
Maximal coverage of the edentulous residual ridge.
Stress control.
4. According to Becker and Kaiser
Rigid major connector.
Multiple positive rest seats.
Mesial rests.
Parallel guide planes.
I-bar clasp design.
Altered-cast technique
The single most important factor in minimizing abutment tooth movement is the
fit of the base. (Tylor and colleagues, Tebrock and colleagues)
The tissue surface of the distal extension RPD should cover the residual ridges at
the most relaxed state when not in function.
5. Importance of altered-cast technique
Holmes and Leupold showed that the altered cast impression technique
demonstrated the least amount of movement of the base at the time of
placement and the most favorable ridge-to-denture-base relationship.
6. Basic technique
The custom resin tray covers the occlusal surfaces of teeth with a minimum of
three definitive stops to ensure repeatable placement in the mouth each
time.
The edentulous ridge was covered with single sheet of wax.
Using fluid wax korecta Wax I-IV applied to tissue surface of the tray, it was
applied incrementally to achieve the final impression.
7. What were the objectives of Applegate
The area covered should be maximized to minimize the work of any given
surface.
Traumatic impact on any area must be avoided so that the workload is spread
as uniformly as possible to avoid impinging on areas with less displaceable
mucosa.
At rest, there must not be any areas of ischemic mucosa.
All areas under load must receive stimulation.
Simultaneous support must be given to the base and the supporting teeth.
Movable border structures should be extended during the making of the
impression to avoid impingement on any functional movement after
completion of the base.
8. Technique
The impression material should be very accurate and easily manipulated to record
the remaining dentition. (in this case you can use elastomeric impression
material, or hydrocolloid in a stock metal tray.
The residual ridge has two forms:
Functional: when tissue is under load.
Anatomic: when tissue at rest.
It is desirable to record the residual ridge in its functional state, thus the material
used to register the ridge may not be suitable to record the teeth.
For this reason the RPD framework is cast and fitted before the altered cast final
impression is made.
This ensure that the metal framework and the base will be related in the same
relationship as that which exist between abutment tooth and the supporting
mucosa when the base has an occlusal force applied.
9. Technique (continue)
Once the framework is fit, an acrylic resin custom tray attached to the metal
framework on the physical retainer.
The tray then border-molded (using impression compound).
Place some vent holes in the tray over the ridge crest and retromolar pad.
Final impression is done with polysulfide rubber impression.
The framework attached to a custom tray that is lined with a wash of
impression, is placed in the patient’s mouth and seated completely without
any pressure on the tray.
The finger pressure is applied only to the parts of the framework that in
contact with teeth.
Pressure on the tray area can cause lifting off of the framework off the teeth.
10. Improper impression can result :
Overstimulation of the underlying bone (due to too much work and poor
stress distribution).
Understimulation of the softer mucosa (due to too little or no work).
Destructive leverage applied to abutment teeth.
12. Laboratory procedure
Two saw cuts are made perpendicular to each other.
1st cut 0.5-1.0mm distal to the most distal remaining tooth and perpendicular
to the edentulous ridge.
This cut carried from outer edge of the cast to 6.0-7.0mm medial to the
lingual vestibule.
2nd cut made parallel and medial to the edentulous ridge, extending from the
most posterior aspect of the cast to the most medial aspect of the 1st cut.
1st and 2nd cuts intersect, the edentulous ridge will separate from the cast.
In case of maxillary arch, provide the internal finish line of the framework
processed against the altered cast.
13. Lab procedure (continue)
The cut surface should have grooves to aid retention of newly poured stone.
Completely seat the framework on the cast.
Lute the framework to the cast via sticky wax.
(an error at this stage will create prosthesis with faulty relationship between
the edentulous ridges and the remaining dentition).
Bead and box, then soak in a cool water bath to saturate the base of the
remaining cast.
Using model stone type III poured and wait to set in minimum 45 minutes.
After the cast prepared remove the acrylic resin tray from the framework.
The frame then fitted back to the cast.
14.
15.
16.
17. Making an index tissue stops
It is mandatory that the occlusal rests be
completely seated during both clinical
and laboratory procedures to avoid over-
or under-displacement of the soft
tissues.
For patients with few anterior teeth
remaining, a condition result in long
distal-extension ridges in which the
rotational stability of RPD is mainly
tissue dependent.
As can be seen tissue stops are touching
the cast on crest ridge.
18. Procedure
For stabilizing the framework in class I
Kennedy, tissue stops are commonly used to
contact the edentulous ridges of the cast.
A 3rd reference point (stone index) placed
under the lingual bar must be used before
altered-cast impression is made.
Why? Because the tissue stops will be covered
by the impression material and will be useless
for re-orienting the framework to the altered-
cast.
19. Procedure
The idea of the stone index is to aid the
occlusal rests in orientation of the
framework to the master cast.
1. Fabricate the framework for RPD and
refine its fit intraorally.
2. Place the framework on the master cast
and fill the space under the bar with
stone.
3. While the framework is on the master
cast, adapt acrylic resin over its
latticework to make a custom
impression tray.
20. Procedure
4. Make a corrected impression of the distal
extension residual ridges at the established
vertical dimension of occlusion and
horizontal jaw relationship.
5. Alter the master cast by aremoving the
residual edentulous ridgend reposition the
completed impression on the sectioned
master cast. The secure it with sticky wax
around the clasp arms.
6. Box the cast and add dental stone to the
impressions of the edentulous portions to
make the altered-cast.
21. Procedure
7. Soak the poured altered-cast in warm
slurry water to soften the impression
material, clean the cast, and reposition the
cleaned metal framework onto the lingual
index of the altered cast.
22. Making framework try-in, altered cast
impression and occlusal registration in one
appointment (Introduction)
This method use detachable custom-made prefabricated impression trays.
It uses this impression as a stable recording base to make the jaw relation
record .
23. Making framework try-in, altered cast
impression and occlusal registration in one
appointment (Procedure)
1. Apply the separating medium on the
master cast.
2. Place the framework on the master cast.
3. Block out all undercuts around the
retentive grid on the edentulous portion of
the framework with wax.
4. Make individual impression trays over the
distal extension bases with
autopolymerizing tray resin.
24. Making framework try-in, altered cast
impression and occlusal registration in one
appointment (Procedure)
5. Remove the tray and trim the excess resin.
6. try-in the framework and adjust it to fit.
7. Place the framework on the master cast and
attach the prefabricated trays with
autopolymerizing resin.
8. adjust the borders and tissue surface of the
bases in the mouth. Examine the thickness of the
tray to be certain that it does not interfere with
the occlusion.
9. Remove any interferences and prepare few
grooves as an index on the occlusal surface of
the tray to permit reseating the jaw registration
material.
25. Making framework try-in, altered cast
impression and occlusal registration in one
appointment (Procedure)
10. Make the altered cast impression with alginate or silicon impression material
and mold the material around the border as it sets.
11. Trim excess of impression especially in the occlusal surface of the denture
base.
12. Make the jaw relation record with accurate registration material (silicon,
polyether, or zinc oxide eugenol).
13. Remove the framework with the distal extension altered cast impression and
the jaw relation record from the patient’s mouth.
14. Box the framework and the altered cast impression with alginate and pour
the altered cast in dental stone.
26. Making framework try-in, altered cast
impression and occlusal registration in one
appointment (Procedure)
27. Making framework try-in, altered cast
impression and occlusal registration in one
appointment (Procedure)
15. mount the maxillary and
mandibular casts in articulator
with the jaw record.
16. After mounting the cast,
remove the registration material,
impression trays, and impression
material from the framework.
(using hot water or alcohol
frame to soften the material).
17. set the teeth and process,
finish and polish.
28. The undercuts are blocked out with wax in the retentive grid areas where
impression trays will be attached.
The surfaces need block-out beneath the retentive grid and around soldered wire
clasps.
Separating medium is applied to the cast, framework and block-out.
29. method to register the mucosa and its
supporting form
Functional reline; after the denture base has been processed onto the
framework, it has disadvantage of greater degree of occlusal adjustment
after the processing of acrylic resin.
Altered-cast method; carried out before the denture bases are processed.
30. Other method to separate the edentulous
portion from the rest of the cast
Separating the cast without use of the plaster saw.
Advantages:
Edentulous portion can be separated easily.
No need to saw the cast or make dovetails for retention.
Edentulous portion can be separated even if cast is wet.
Disadvantage:
The cast cannot be used with hydrocolloid impression because it require quick
pouring of the impression.
The impression cannot be boxed because it will distort as a result of pressure.
31. Other method to separate the edentulous
portion from the rest of the cast (Procedure)
1. Make a bar with baseplate wax with shape of a 5mm equilateral triangle in
cross section. It should be made in advance to save time.
2. Cut several pieces of the wax bar 15mm long and set them aside.
3. Box the elastomeric final impression.
4. Separate the edentulous ridges distal to the last tooth in the impression by
contouring a piece of baseplate wax to fit the anatomic contour of the
impression, and seal it to the base to make three separate compartments of
the impression. If separating wax is not close enough to the distal surface of
the last tooth of the impression, the edentulous portion of the cast left distal
to the last tooth can be trimmed after the edentulous pieces of the cast are
removed.
32. Other method to separate the edentulous
portion from the rest of the cast (continue)
5. wax the 15mm long pieces of triangular wax bars to the separating baseplate
wax. Make the apex of the triangle sealed securely to the separating baseplate
wax toward the tongue side and anterior to the edentulous ridge.
6. fill the three compartments with dental stone above the level of separating wax
to make a master cast.
7. after setting of stone, remove the boxing wax and impression and trim the base
of the cast until a stone base at least 3 to 5 mm thick remains below the
separating wax. (to prevent premature separation).
8. after making framework, and fitted to the cast and patient’s mouth, place the
framework on the cast and adapt a shellac baseplate or form an acrylic resin
baseplate over the edentulous retention portion of the ridges and proceed to
make the impression. After displacement impression is made, separate the
edentulous portion of the original cast and discard it, to permit placing the
framework with the new impression on the original cast.
33. Other method to separate the edentulous
portion from the rest of the cast (continue)
9. soak the cast in slurry water for 3-5 minutes and trim the base of the cast
up to the line to expose the separating wax.
10. put the master cast in boiling water for 5 minutes. The clear slurry water
should be saturated with stone in order not to dissolve the cast.
11. after melting the wax, the edentulous portions will be separated from the
rest of the cast and dovetails will appear.
12. flush to remove all wax, seat the framework with the new impression and
pour the new portions of the cast. (if too much of the old edentulous ridge is
left, the framework with the new impression may not seat well. (use sharp
knife to trim the ridge back to the distal side of the last tooth).
34. Other method to separate the edentulous
portion from the rest of the cast
35. In 2004, (Richard et al.) compared between altered case and one-piece cast with
regard to base support, abutment health, and patient comfort over time. He
reported that the altered cast impression procedure does not offer significant
advantages over the one-piece cast, provided the standards used in his are met,
including a completely extended impression, use of magnification to adjust and
ensure complete framework seating, and coverage of the retromolar pad and
buccal shelf by the base.
He reported that those studies which are in favor of ACIP did not involve more
than 7 subjects and 2 studies and the evaluation of base support done in a manner
not used in clinical practice.
It was hypothesized that there would be no difference between the ACIP and OPC
relative to these variables: border extension, frequency/amount of base
adjustment needed, base movement, base adaptation, need for reline, changes in
direct abutment mobility, gingival index, sulcus depth, quality of posterior
occlusion, health of tissues beneath the RPDs, patient satisfaction, time worn, and
soreness reported by the patient. All were accepted in the result except for border
extension and adaptation of the base to the ridge crest.
Under extension was noted in 22% of the OPC and in none of the ACIP.
Causing of under-extension could be: difficulty to recognize anatomical
landmarks, underextended impressions, under-waxed or over-finished bases,
aggressive base adjustment, lack of space, or patient demand.
36. Although Maxfield et al. reported that ACIP decreases the load on the direct
abutments, it does not appear that such difference has any detrimental
effect. But the increase in inflammation around the direct retainer
underscores the importance of periodic reinforcement of oral hygiene
instructions (Bregman et al)
To substitute ACIP, three conditions should be met; a framework that exhibit
complete seating under x2.5 magnification, the impression records all
applicable landmarks, and the base extension is neither under-extended nor
over-finished.
Otherwise, the practitioner should either use the ACIP, a custom impression
tray, or evaluate base movement during framework evaluation with an
attached occlusion rim (if movement is noted ACIP should be performed).
37. Framework fit and altered cast impression
Problems that may arise because the impression material being placed between
framework and mucosa, which lift away the framework from the mucosa; subsequently,
during flasking, the framework will depress again, producing inaccuracies in the
prosthesis.
Pressing down on the framework while making the impression, may give inacceptable
results, because it is difficult to judge how much pressure to exert; in addition, the act of
pressing down may itself cause slight displacement.
An alternative approach is to take the altered cast impression first, and then to obtain
jaw relation record in silicon; however, major two disadvantages come ahead; first, it is
difficult to ensure that the framework will remain in the correct position. Second, the
impression material used for obtaining the jaw relation record may be displaced slightly,
leading to inaccuracies in the final structure.
Another approach is to use the framework as record base; however, this procedure is
also sometimes inaccurate.
38. Framework fit and altered cast impression
Check the fit of framework for its passive fit and absence of occlusal interferences.
Make a tray base by light-cured acrylic resin, modeling compound or thermoplastic
baseplate material.
39. procedure
1. Build ¼ inch diameter column of light-cured resin on the resin-retention part of the
framework in the position corresponding to the hole in the acrylic resin tray. Extend
the column up to the opposing occlusion in the correct jaw relation. This tripod of
anterior teeth and two columns distally ensures the framework seating in the same
way each time.
2. Remove the framework and seat it on the master cast and mount it on an
articulator with an opposing cast. A stone index prepared below the lingual major
connector, facilitating and improving positioning when the framework is reseated
on the altered master cast. Enlarge the holes, if necessary, in the bases so that they
fit correctly over the resin columns. Seat the bases over the framework and heat
them and adapt them to the framework, making certain that they are firmly
attached to it.
41. Procedure
3. place framework with the base in the mouth and relieve over-extensions and
pressure spots, then apply low heat softened compound to the borders and border
mold it.
4. remove the framework-tray complex, apply impression wax into the tray, then
reinsert the whole structure and maintain it in the mouth while the wax adapts to
the edentulous ridge. Ask the patient to make molding movements.
5. remove the edentulous ridge from the cast by two cuts, longitudinal and at right
angle to the longitudinal axis of the ridge, 1mm distal to the abutment.
43. Procedure
6. score the cut surfaces with a knife or bur to ensure good attachment of the new stone
to the old.
7. position the framework-impression assembly on the cast, making sure the framework
seating correctly on the teeth and in the index for the bar. If there is any chance of
change in positions during the boxing procedure, wax it securely in place with sticky
wax.
8. bead and box the cast with wax. And seal it very well.
9. pour a mix of stone and allow it to set.
10. remove block-out and boxing from the cast but do not separate framework-
impression assembly from the cast.
11. mount mandibular cast in articulator after reassuring the correct position of resin
against maxillary cast.
12. remove framework-impression assembly.
45. Discussion
The index overcome the problem of too much or less pressure exerted during
impression, ensuring correct position during impression taking.
The index act as jaw relation record.
This photochemical index is more reliable than elastomeric material which does not
remain joined to the impression.
A minor disadvantage, if the patient has an antagonist edentulous area. To avoid
such problem instruct the patient not to clench tightly, but simply bring the
maxillary and mandibular arches together
Advantages; molding can be made with mouth closed, require little time, can be
performed in clinic without new jaw relation trays, obviates the stage of functional
and harmonious occlusion, and stable and rigid jaw relation index.
46. Stereolithographic resin pattern
Using CAD/CAM/RP technologies, a one-piece stereolithographic resin structure is used
for making framework evaluation, altered-cast impression, and maxillomandibular
relationship record in a single appointment.
Procedure:
1. Scanning the cast, then design the framework with CAD software.
2. Make altered cast impression trays based on the original framework design.
3. Transfer the finished design to rapid prototyping machine.
4. Make a stereolithographic resin pattern of the framework and cast it.
5. Print the one-piece stereolithographic resin structure of the altered cast impression trays and
record rims.
6. Make altered cast impression with compound border molding and polyvinyl siloxane material.
Obtain maxillomandibular relationship with occlusal registration material.
7. Mount the cast in the articulator, remove the 1-piece stereolithographic resin structure from
the altered cast and place the cast framework.
47.
48. Using altered-cast technique in prosthetic rehab
of a patient after a maxillectomy
After primary impression capturing the crowns was made with irreversible
hydrocolloid impression material. This captures all the intraoral structures of non-
resected side and part of the resection defect with sufficient extension for the
production of a cast framework for the maxillary obturator.
Poured with dental stone, a maxillary obturator cast framework produced from Co-
Cr-Mo alloy. The cast framework was modified in such a way that retentive mesh
and dowels were added over the resection defect to ensure retention for secondary
alter cast impression material and for acrylic resin bulb of the obturator.
An altered cast impression was made with condensation high and low viscosity
silicone materials placed on and inserted intraorally with the obturator framework
serving as the tray.
49. Procedure (continue)
The stone cast was altered and the portion of the cast corresponding to the
resection defect was trimmed until it was possible for the obturator cast framework
to be place on it with altered cast impression, then it was poured in dental stone.
The predicted shape of maxillary sinus was formed by using polyvinyl siloxane to
produce a concave shape of the obturator toward sinus cavity.
The hollow bulb obturator was made by pouring autopolymerizing acrylic resin in
the newly formed resection defect on the altered cast, covering retentive elements
of the case framework.
50.
51. References:
Santana-penin U., Gil Lozano J. 1998, ‘an accurate method for occlusal registration and altered-cast impression for removable partial
dentures during the same visit as the framework try-in’, the journal of prosthetic dentistry, vol. 80, no. 5, pp. 615-618.
Ansari 1994, ‘a new procedure for separating the edentulous distal extension portion from the master cast when an altered cast is
made’, the journal of prosthetic dentistry, vol. 72, no. 6, pp. 666-669.
Daniel B. 1999, ‘the altered cast technique revisited’, JADA, Vol. 130, October, pp. 1476-1481.
Frank Richard P., Brudvik James S., Noonan Carolyn Jean 2004, ‘clinical outcome of the altered cast impression procedure compared
with use of a one-piece cast’, the journal of prosthetic dentistry, Vol. 91, no. 5, pp. 468-476.
Lay Lih-Shou, Lai Wing-Hong, Wu Chen-Tsye 1996, ‘making the framework try-in, altered-cast impression, and occlusal registration in
one appointment’, the journal of prosthetic dentistry, Vol. 75, no. 4, pp. 446-448.
Lee Ju-Hyoung, Lee Cheong-Hee 2015, ‘a stereolithographic resin pattern for evaluating the framework, altered cast partial removable
dental prosthesis impression, and maxillomandibular relationship record in a single appointment’, the journal of prosthetic dentistry,
Vol. 114, no. 5, pp. 625-626.
Lund Peter S., Aquilino Steven A. 1991, ‘prefabricated custom impression trays for the altered cast technique’, the journal of prosthetic
dentistry, Vol. 66, pp. 782-783.
Shifman Arie 1991, ‘index to reposition the metal framework accurately on the altered cast’, the journal of prosthetic dentistry, Vol. 68,
pp. 979-981.
Vojvodic Denis, Kranjcic Josip 2013, ‘a two-step (altered cast) impression technique in the prosthetic rehabilitation of a patient after a
maxillectomy: a clinical report’, the journal of prosthetic dentistry, Vol. 110, no. 3, pp. 228-231.
THE ALTERED CAST IMPRESSION TECHNIQUE REVISITED reference
Studies have shown that a well-fitting denture base distributes stresses favorably to the supporting bone and abutment teeth.
And others showed that increased residual ridge coverage coupled with a well-fitting denture base reduces stress per unit area, potentially preserving the remaining supporting structures. 2. Leupold RJ, Kratochvil FJ. An altered cast procedure to improve tissue support for removable partial dentures. J Prosthet Dent 1965;15:672-8.
It was originally described by Applegate in 1937.
Applegate OC. The cast saddle partial denture. JADA 1937;27:1280-91.
Steffel VL. Clasp partial dentures. JADA 1963;66:803-11.
Becker CM, Kaiser DA, Goldfogel MH. Evolution of removable partial denture design. J Prosthodont 1994;3:158-66.
Taylor DT, Pflughoeft FA, McGivney GP. Effect of two clasping assemblies on arch integrity as modified by base adaptation. J Prosthet Dent 1982;47:120-5.
Tebrock DC, Rohen RM, Fenster RK, Pelleu GB. The effect of various clasping sys- tems on the mobility of abutment teeth for distal extension removable partial dentures. J Prosthet Dent 1979;41:511-21.
Holmes JB. Influence of impression proce- dures and occlusal loading on partial denture movement. J Prosthet Dent 1965;15:474-81.
Leupold RJ. A comparative study of impression procedures for distal extension removable partial dentures. J Prothet Dent 1966;16:708-20.
Steffel VL. Clasp partial dentures. JADA 1963;66:803-11.
Index to reposition the metal framework accurately on the altered cast.
Index to reposition the metal framework accurately on the altered cast.
Index to reposition the metal framework accurately on the altered cast.
Index to reposition the metal framework accurately on the altered cast.
Index to reposition the metal framework accurately on the altered cast.
Making the framework occlusal registration try-in, altered-cast impression, and in one appointment Lih-Shou Tainan Republic Lay, Municipal of China DDS,a Wing-Hong Hospital, Tainan, Lai, DDS,b and Chen-Tsye Wu, DDSe and Show Chwan Memorial Hospital, Changhua, Taiwan,
Prefabricated custom impression trays for the altered cast technique Peter S. Lund, DDS, MS, and Steven A. Aquilino, DDS, MSb University of Iowa, College of Dentistry, Iowa City, Iowa
Clinical outcome of the altered cast impression procedure compared with use of a one-piece cast
Richard P. Frank, DDS, MSD,a James S. Brudvik, DDS,b and Carolyn Jean Noonan, MSc School of Dentistry, University of Washington, Seattle, Wash
Maxfield JB, Nicholls JI, Smith DE. The measurement of forces transmitted to abutment teeth of removable partial dentures. J Prosthet Dent 1979; 41:134-42.
Bergman B, Hugoson A, Olsson CO. Caries, periodontal and prosthetic findings in patients with removable partial dentures: a ten-year longitudinal study. J Prosthet Dent 1982;48:506-14.
An accurate method for occlusal registration and altered-cast impression for removable partial dentures during the same visit as the framework try-in
U. Santana-Penín, MD, PhD,a and J. Gil Lozano, MD, PhDb
Faculty of Medicine and Odontology, University of Santiago de Compostela, Santiago de Compostela, Spain
A two-step (altered cast) impression technique in the prosthetic rehabilitation of a patient after a maxillectomy:A clinical report
Denis Vojvodic, DMD, PhDa and Josip Kranjcic, DMDb
School of Dental Medicine, University of Zagreb, Zagreb, Croatia