This document discusses relining and rebasing procedures for complete dentures. It defines relining as adding material to the denture base to improve fit, while rebasing involves replacing the entire denture base. Relining is indicated when dentures lose adaptation due to ridge resorption. Closed mouth techniques take impressions with the teeth in occlusion, while open mouth techniques record a new bite relationship. Impression materials and lab procedures are also outlined. The goal of relining is to prolong the useful life of dentures by improving fit as the ridges change.
Fixed partial dentures transmit forces through the abutments to the periodontium. Failures are due to poor engineering, the use of improper materials, inadequate tooth preparation, and faulty fabrication. Of particular concern to prosthodontist is the selection of teeth for abutments. They must recognize the forces developed by the oral mechanism, and resistance.
Successful selection of abutments for fixed partial dentures requires sensitive diagnostic ability. Thorough knowledge of anatomy, ceramics, the chemistry and physics of dental materials, metallurgy, Periodontics, phonetics, physiology, radiology and the mechanics of oral function is fundamental.
Fixed partial dentures transmit forces through the abutments to the periodontium. Failures are due to poor engineering, the use of improper materials, inadequate tooth preparation, and faulty fabrication. Of particular concern to prosthodontist is the selection of teeth for abutments. They must recognize the forces developed by the oral mechanism, and resistance.
Successful selection of abutments for fixed partial dentures requires sensitive diagnostic ability. Thorough knowledge of anatomy, ceramics, the chemistry and physics of dental materials, metallurgy, Periodontics, phonetics, physiology, radiology and the mechanics of oral function is fundamental.
This presentation specifically deals with the maxillary and mandibular Major connectors used in a cast partial denture. it also mentions the uses, advantages and disadvantages of each,
Failures in Fixed Partial Denture
(Prosthodontics FPD- Dental science)
Various types of failures in the fabrication of fixed partial denture
Dr.Sachin Sunny Otta
St.Gregorios Dental College,Kothamangalam,Ernakulam
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.for more details please visit
www.indiandentalacademy.com
a detailed account of the principles of tooth preparation with main reference from Shillingburg
The presentation is available on request. Mail me at apurvathampi@gmail.com
This presentation specifically deals with the maxillary and mandibular Major connectors used in a cast partial denture. it also mentions the uses, advantages and disadvantages of each,
Failures in Fixed Partial Denture
(Prosthodontics FPD- Dental science)
Various types of failures in the fabrication of fixed partial denture
Dr.Sachin Sunny Otta
St.Gregorios Dental College,Kothamangalam,Ernakulam
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.for more details please visit
www.indiandentalacademy.com
a detailed account of the principles of tooth preparation with main reference from Shillingburg
The presentation is available on request. Mail me at apurvathampi@gmail.com
Periodontal plastic surgery is defined as the surgical procedures performed to correct deformities of the gingiva or alveolar mucosa. It includes widening of attached gingiva,
deepening of shallow vestibules, resection of the aberrant frena, depigmentation of gingiva.In all of these procedures, blood supply is the most significant concern and must be the underlying issue for all decisions regarding the individual surgical procedure.
Useful for prostho treatment.
Mainly for final yr.
In the case of complete denture.
For Aesthetic use.
Introduction.
Definitions.
Basic requirement of an impression making.
Principles of an impression making.
Objectives of an impression making.
Anatomical landmarks.
Classification of an impression making.
Steps in making an impression.
Impression :-
A negative likeness or copy in reverse of the surface of an object, an imprint of the teeth and adjacent structures for use in dentistry
(GPT8)
An impression can also be defined as an imprint of the teeth and adjacent structures for use in dentistry.
(GPT 4)
journal cub presentation on Bps denture/biofunctional prosthetic systemNAMITHA ANAND
watch video links below for better understanding
https://www.youtube.com/watch?v=_sR2Ip5p9RE
its a series of videos 1-7 beautiful videos explaining the construction of BPS DENTURES - step by step
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
Thanks...!
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
2. Content
• Introduction
• General considerations
• Indications
• Contraindications
• Preliminary treatment
A. Tissue preparation
B. Denture preparation
3. • Relining materials
• Relining procedures
a) Clinical procedures
b) Laboratory procedures
• Conclusion
• References
4. Introduction
The residual ridges have been described as plastic in
nature, always changing in topography and morphology from
many causes, some known and many unknown.
Every edentulous patient should be examined on an
annual basis to determine (among other things) the rate of
resorption of the residual ridges.
5. There is some clinical evidence to suggest that the rate
of osseous change can be retarded when complete dentures
are readapted to the residual ridges at the first signs and
symptoms of loss of adaptation.
The clinical efforts that aim at prolonging the useful life of
complete denture involve a refitting of the impression surface of
a denture by means of a reline or a rebase procedure
6. Definitions
• Relining: it is the process of adding some material to the tissue
side of denture to fill the space between the tissue and the
denture base.
• Rebasing: it is the process of replacing all the base material of
a denture.
Nikzad S. Javid, , John F. Bowman ; Relining and Rebasing Techniques Essentials of compete denture
prosthodontics; 341-354
7. GPT 9:-
•Reline:-the procedures used to resurface the intaglio of a
removable dental prosthesis with a new base material, thus
producing an accurate adaptation to the denture foundation area.
•Rebase:-the laboratory process of replacing the entire denture
base material on an existing prosthesis
8. Indications
• Immediate dentures at 3 to 6 months
• the adaptation of the dentures to the ridges is poor
• the cost of new dentures
• physical or mental stress such as for geriatric or chronically ill
patients.
9. Contraindications
• Excessive amount of resorption
• When abused soft tissues are present.
• When the patient complains of T.M.J problems.
• Poor esthetics and Unsatisfactory jaw relationships.
• Speech problem
• Severe osseous undercuts
10. General Considerations (Diagnosis)
A thorough examination of the patient and the denture must
be accomplished before commencing the therapy.
The following points should receive special consideration:-
11. • Vertical dimension
• Centric occlusion should coincide with centric relation
• The size, shape, shade, and arrangement of the artificial
teeth must be satisfactory.
• The oral tissues should be in optimum health.
• The posterior limit of the maxillary denture is correct
12. • Adequate denture base extension
• The denture base extensions ensure distribution of
masticatory forces over as large an area as possible.
• The interocclusal distance is correct
• Speech is satisfactory
• Redundant tissue or severe osseous undercuts
14. Tissue preparation
•Hypertrophic tissues
•Oral mucosa should be free of areas of irritation.
•Removal of the dentures from the mouth during sleep is a must
for several weeks.
•The dentures should be left out of the mouth at least two to
three days before making final impression.
•Daily massage of the soft tissue
15. Denture preparations
• Pressure areas of the tissue surface of the denture
• Minor occlusal disharmony is corrected by selective
grinding.
• Small border inadequacies are corrected.
• A correct posterior palatal seal area should be established
before the final impression.
16. Principal Pitfalls
Must be avoided in any technique to refit a complete denture :-
1.Do not increase the occlusal vertical dimension.
2.Do not permit the maxillary denture to move forward during
impression making.
17. 3. Ensure that centric relation and centric occlusion are identical.
4. Ensure that an accurate posterior palatal seal has been
established.
5. An equal thickness of final impression material should be
used.
18. RELINING MATERIAL
According to ISO:According to ISO:
1.1.Short term liners/tissue conditionersShort term liners/tissue conditioners
2.2.Intermediate linersIntermediate liners
3.3.Long term linersLong term liners
Gracia LT. Soft Liners.Dent Clin N Am 48 (2004) 709–720
19. • Short-term liner as one used intraorally for up to 30 days.
• An intermediate liner placed in a removable prosthesis
usually lasts for 1 to 2 months
• A long-term liner is categorized as one that maintains
softness and elasticity for more than 30 days
20. Tissue conditioners
• Soft denture liners which may be applied to the fitting
surface of a denture.
• Provide a temporary cushion.
• Should undergo a degree of plastic flow for 24-36 hours
after mixing
22. Mechanism Of Action
• The plasticizers used are large molecular species such
as dibutyl phthalate.
• The distribution of large plasticizer molecules minimize
the enlargement of polymer chains and thereby permits
the individual chains to slip past one another.
• The slipping motion enables rapid change in shape of
the soft liner and provides cushioning effect to the
underlying soft tissues.
23. INTERMEDIATE LINERS
• Liners used for 1-6 months
• Are made of plasticized acrylic
• Plasticizers leach out in 1-2 months and the material loses
its resiliency
24. LONG TERM LINERS
• Also called as permanent soft liners
• Increases patient tolerance for tissue pain associated with hard
resin denture base
Various material:-
• Acrylic
• Silicone rubbers
• Polyphosphazene fluroelastomers
25. Acrylic
• Heat cure or self cure.
• Powder consists of beads of polyethyl or polybutylmethacrylate
along with some peroxide initiator and pigment.
• The liquid is a mixture of butyl methacrylate and plasticizers.
• The presence of free monomer results in inferior mechanical
properties and reduced biocompatibility.
26. Silicone rubbers
• Heat cure or cold cure or room temperature vulcanization
(RTV).
• The liner sets by a cross-linking reaction that is catalyzed by
heat and the peroxide initiator.
• It is processed against the acrylic dough of the denture
• The materials are supplied as paste and liquid
29. Static Impression Technique
Static impression technique involves the use of either a closed or
open mouth reline/rebase procedure.
•In closed mouth technique the dentures are used as an
impression trays and either the existing centric relation occlusion
(CRO) is used or the centric relation (CR) is recorded before the
impressions are made.
30. • In open mouth method, the dentures are used essentially as
trays for making the new impressions, which may be done for
both the jaws at the same appointment.
• The existing centric occlusion is not used, and a new centric
relation occlusion record is obtained after the impressions
have been made.
32. Technique A
Centric relation: - a new centric relation record is made using
wax or modeling compound
Denture preparation: -
•large undercuts are relieved
•borders are reduced 1-2 mm except the posterior border of
maxillary dentures.
Shaffer FW, Filler WH: Relining complete denture with minimum occlusal error J Prosthet Dent 1971;25:366-370
33. Special suggestion:-
Shaffer FW, Filler WH: Relining complete denture with minimum occlusal error J Prosthet Dent
1971;25:366-370
A part of the palate of the maxillary denture is removed to aid in
the proper positioning of the denture when the final impression
for the reline is made.
34. Border molding:-The borders of the dentures are reformed to
their functional contours by using low-fusing modeling compound.
Impression Zinc oxide-eugenol impression paste is suggested as
the impression material.
During impression making, the patient closes lightly into the
premade interocclusal record.
Shaffer FW, Filler WH: Relining complete denture with minimum occlusal error J Prosthet Dent
1971;25:366-370
35. Light jaw closure on the interocclusal
record is maintained with the mandible in
centric relation until the final impression
material has set.
A fast-setting impression plaster
fills the palatal opening in the
denture.
36. Advantages
1.The opening of the palatal portion will allow better seating of
the maxillary denture
2.The premade interocclusal record helps to position the
dentures
Shaffer FW, Filler WH: Relining complete denture with minimum occlusal error J Prosthet Dent
1971;25:366-370
37. Disadvantages
1.The possibility of moving the maxillary denture
2.The wax interocclusal record is not an accurate and safe record
3.Relining of both dentures at the same time.
Shaffer FW, Filler WH: Relining complete denture with minimum occlusal error J Prosthet Dent
1971;25:366-370
38. Technique B
• Centric relation Existing centric occlusion and intercuspation
are used as a means to seat the dentures.
• Denture preparation The same as for technique A.
Hansen NJ: Rebasing and relining complete dentures: A technique. Dent Clin North Am 1964;8:693-704
39. Special suggestion A large part of the palatal section is prepared
to be removed as follows:
•outline of the area should be indicated and deepened on the
polished surface up to half the thickness of the base.
•Holes are drilled at 5- to 6-mm intervals inside this groove.
Hansen NJ: Rebasing and relining complete dentures: A technique. Dent Clin North Am 1964;8:693-
40. • This procedure is suggested for easy removal of the palatal
portion during packing and processing
Border molding Low-fusing modeling compound (green stick)
is suggested for border molding.
Impression Impression wax is material of choice in this
technique
Hansen NJ: Rebasing and relining complete dentures: A technique. Dent Clin North Am 1964;8:693-704
41. Disadvantages
(1) Wax impression material is difficult to work with and the
possibility of distortion exists.
(2) Errors of existing centric occlusion can produce an inaccurate
impression
Hansen NJ: Rebasing and relining complete dentures: A technique. Dent Clin North Am 1964;8:693-704
42. Technique C
Centric relation The same as in technique B.
Denture preparation The same as in techniques A and B.
Special suggestion The labial and palatal flanges of the denture
are perforated.
Christensen FT: Relining techniques for complete dentures. J Prosthet Dent 1971;26:373-381
43. Border molding The same as techniques A and B.
Impression No specific impression material recommended.
Christensen FT: Relining techniques for complete dentures. J Prosthet Dent 1971;26:373-381
44. Technique D
Centric relation The existing centric occlusion is used to seat
the maxillary denture.
Denture preparation The same as in the other techniques.
Impression Plaster of Paris or zinc oxide eugenol is suggested
for the first step of impression making, and plaster of Paris for the
second step (the palatal portions).
Jorden LG : Relining the complete denture. J Prosthet Dent 1972;28:637-641
45. Disadvantage :- the existing errors of centric occlusion may
produce some pressure points and a faulty impression can result.
Jorden LG : Relining the complete denture. J Prosthet Dent 1972;28:637-641
47. Technique
Centric relation The existing centric occlusion is used as a
means to seat the mandibular denture during the secondary
impression.
The occlusion is corrected during the establishment of a new
occlusal vertical dimension.
Denture preparation Not specified.
Gillis RR: A relining technique for mandibular dentures. J Prosthet Dent 1960;10:405-410
48. Special suggestion Loss of vertical dimension is corrected by
luting softened modeling compound to the occlusal surfaces of
the mandibular posterior teeth.
Gillis RR: A relining technique for mandibular dentures. J Prosthet Dent 1960;10:405-410
49. • The patient is directed to repeatedly pronounce the letter “m.”
• The record is chilled, trimmed, and slightly heated before
returning it to the patient’s mouth.
• The procedure is repeated until the occlusal vertical dimension
is established to the operator’s satisfaction.
50. • Then a lower impression is made.
• After pouring the impression and mounting the lower denture
on an articulator
• Any excessive undercuts should be removed.
• The denture is luted to the maxillary denture in maximum
intercuspation.
Gillis RR: A relining technique for mandibular dentures. J Prosthet Dent 1960;10:405-410
51. • Softened modeling compound is placed inside the mandibular
denture
• the articulator closed against the lower cast to contact the
incisal guide pin.
• With this procedure, the amount of vertical dimension indicated
by the thickness of the compound on the surface of the
mandibular teeth is transferred to the base of the mandibular
denture.
• The mandibular denture at this stage is used as a tray for
making the final impression.
Gillis RR: A relining technique for mandibular dentures. J Prosthet Dent 1960;10:405-410
52. • Impression Modeling compound at the early stage and zinc
oxide-eugenol for making the secondary impression are
suggested.
Advantages
(1) The loss of vertical dimension can be compensated for during
the relining procedures.
(2) The error in centric occlusion can be reduced during the
laboratory stages.
Gillis RR: A relining technique for mandibular dentures. J Prosthet Dent 1960;10:405-410
53. Disadvantages:-
(1) This technique is very time consuming from the standpoint
of clinical and laboratory procedures.
(2) The procedure for establishment of occlusal vertical
dimension is highly questionable
Gillis RR: A relining technique for mandibular dentures. J Prosthet Dent 1960;10:405-410
55. • Boucher’s technique
• A method for relining the mandibular and maxillary dentures
at the same time.
56. • The impressions are made independently
• Dentures are used as the trays
• A new centric relation record is made.
57. Technique
Centric relation :-the jaw relation is recorded after making the
secondary mandibular and maxillary impressions.
Denture preparation
•A posterior palatal seal is formed in modeling compound.
•1 mm of space is provided inside the denture
• The borders are shortened 1 mm
Boucher CO: The relining of complete dentures. J Prosthet Dent 1973;30:521-526
58. Special suggestion The lower denture is prepared for the reline
impression
•The lingual flange and the labial flange are shortened by 1 mm.
•Handel is formed over the lower anterior teeth
•Adhesive or masking tape is adapted over the polished surfaces
of both dentures and over the teeth.
Boucher CO: The relining of complete dentures. J Prosthet Dent 1973;30:521-526
59. Border molding If the flanges are inadequate, the borders should
be corrected with modeling compound.
Impression Zinc oxide-eugenol impression
Boucher CO: The relining of complete dentures. J Prosthet Dent 1973;30:521-526
60. Advantages
1.No occlusal interference during impression making.
2.It is possible to verify the centric relation record if necessary
3.The interocclusal record, which is made with quick-setting
plaster, is a reliable one.
Boucher CO: The relining of complete dentures. J Prosthet Dent 1973;30:521-526
61. Disadvantages
1.Although this technique seems simple, the performance of the
procedures is not easy.
2.This technique requires more clinical and laboratory time
Boucher CO: The relining of complete dentures. J Prosthet Dent 1973;30:521-526
62. Functional Impression Technique
• It is a simple practical and most commonly used procedure.
• It depends on a thorough understanding of the versatile
properties of tissue conditioners as functional impression
material.
63. Procedure:-
The dentures are observed intraorally to assess
•the need for peripheral reduction or extension and a
•posterior palatal seal extension is developed with modeling
compound on maxillary denture.
64. In case of extensive resorption
•three compound stops may be required to reestablish a proper
occlusal relationship.
A treatment liner is next placed inside the denture.
65. • If voids are evident they should be filled with a fresh mix of
liner material
• The patient’s mandible is guided into a retruded position- helps
stabilization
• Excess material is trimmed away with a hot sharp scalpel
66. • The patient is instructed regarding care of the prosthesis and its
lining material.
• Simple rinsing of the temporary lined denture and gentle
brushing with soft toothbrush is recommended.
67. Stages of tissue conditioning
Plastic Stage :
Elastic Stage :
Firm Stage :
Denture base responds to functional/parafunctional
stresses; fit is improved (few hrs to few days)
Stress is cushioned and tissue recovery takes place
(1-2 weeks)
Surface similar to polymerized resin, except it is
vulnerable to deterioration (after 15 days)
68. • 10-14 days should elapse before the material is firm enough to
proceed with the clinical relining sequence.
• At the next appointment, the underextentions, denuded areas
and the pressure spots are corrected by trimming and/or by
adding new material.
69. • The material is changed periodically till the tissues return to a
state of health and then the patient is scheduled for final
impressions
70. Chair Side Technique (Heartwell)
• When patients have abused tissues and the dentures need to
be made to fit by rebasing or new dentures are to be made,
chairside reline procedures may be a part of the treatment
plan.
• When the tissue abuse is extensive, the reline procedures may
be repeated until the tissue response is considered
satisfactory.
71. • The chairside reline or rebase procedures are essentially the
same.
• In one, the reline material is used and in the other an
impression material is used.
• The occlusion is corrected in both procedures; therefore, they
both are considered in the following:
72. 1. Instruct the patient about the use and care of dentures.
2. Instruct the patient to leave the dentures out of the mouth at
least 8 hours, preferably at night, for 4 or 5 days.
3.Before a morning appointment he should remove the dentures
for 48 to 72 consecutive hours, depending on the extent of
abuse.
73. 4. Reduce the borders of the maxillary denture approximately 2
mm below the vestibular spaces and frenal attachments and
refine with impression compound.
5. Relieve the tissue side of the maxillary denture base in all
areas covering stress-bearing mucosa.
74. Mix the relining or impression material according to the
manufacturer’s instructions.
75. Load the denture with the mixed material.
It is important to apply an even coating of 2 or 3 mm to the entire
tissue surface, including the borders.
76. Seat the denture with an
anteroposterior path of insertion.
When the denture is seated,
instruct the patient to close the
jaw until tooth contact is made.
77. When you are sure that the teeth are in the correct anteroposterior
relation, support the denture with the middle and index fingers in
the bicuspid area.
Instruct the patient to open the jaws to a relaxed position, to
protrude and retrace the lips as in grinning, to swallow, and to
relax the jaws.
78. Avoid pressure when inserting the denture.
Allow the material to set. Remove the impression, bead, box,
and pour the cast in Hydrocal
After the denture base material has been removed and replaced
with processed acrylic resin (rebased), remount procedures are
done
79. The mandibular impression is made in the following manner:-
1.Allow the maxillary denture to remain in the stable fitted
position.
2.Remove the mandibular denture, dry the teeth, and apply
occlusal indicator wax.
80. 3. Insert the mandibular denture and instruct the patient to chop
the teeth together with the jaws in centric relation.
Reduce the premature or heavy contacting areas until an even
contact of the posterior teeth is assured.
81. Lab Procedures
• The process of replacing the impression material with acrylic
resin is same for either the static or the functional approach.
• The difference between relining and rebasing is in the amount
of old dentures base removed and replaced.
• For rebasing, the entire denture base is eliminated excepting
the teeth and may be 2mm of adjoining denture base.
82. One of the following method can be used:-
•Flask method
•Articulator method
•Jig method
84. The relined impression is
poured with the dental stone.
The master cast is poured
around the impression made by
beading and boxing
85. This cast provides the surface
against which the denture is
relined by embedding it in a
processing flask.
The flask is warmed to soften the
impression compound before
opening it to remove the
impression material.
86. • Heat polymerized denture
base resin is packed into the
mould.
• The flask is then closed and
clamped to ensure
maintenance of occlusal
vertical dimension.
• After processing the flask is
cooled slowly and the
denture is retrieved from
stone mould, finished and
polished.
87. Articulator method
• Master cast is poured. It is not separated from the impression.
• A layer of plaster is arranged in platform fashion on the lower
member of the articulator.
88. • cast with the relined impression on the wet plaster
platform
• the teeth penetrate the plaster surface to a depth
of 2mm & occlusal plane is parallel to the floor.
allows repositioning of the teeth maintaining the
distance and the relation with the cast.
• additional plaster is placed on the base of the cast
• it is mounted on the upper member of articulator.
89. When mounting sets, denture with the impression can be
separated from the cast.
At this point one may elect to rebase or reline the denture. It
differs only in amount of trimming of denture.
90. The denture base is waxed, cast, and the denture are removed
from the mounting, flasked, and processed with heat-cure
denture base acrylic resin.
91. Jig method
Definition: - A jig is a device used to maintain mechanically a
positional relationship between a piece of work and a tool or
between components during assembly or alteration. (GPT9)
92. •Procedure is similar to that of an articulator.
•Seat the occlusal surface of the denture on the plaster platform
on lower member of relining jig.
•After the stone index is made, mount the denture with the cast to
the upper member in reline jig similar to articulator method.
93. • Open the jig, remove the teeth from denture base and adapt
baseplate wax on the cast and wax the denture.
• After processing, replace the cured denture, check and
correct occlusion using the indentation made in the jig during
mounting of denture.
94. • Alternatively a Hooper’s duplicator can also be used. It is
similar to jig method.
95. Conclusion
Resurfacing and replacement of the denture base of a
complete denture is a complicated procedure requiring astute
clinical judgment and skill if the therapy is to be successful.
96. A relined compete denture should be remounted on the
articulator and the occlusion refined to eliminate occlusal
interferences resulting from three-dimensional denture
displacement during relining.
Relining and rebasing are not adequate substitute for new
dentures.
97. However, rebased or relined dentures should be given the
same care as now dentures, and the patients should be recalled
as often as necessary for examination of the tissue and the jaw
relations.
98. References
• Hickey.J, Zarb.G. Prosthodontic treatment for edentulous
patients 13th
ed
• Nikzad S. Javid, , John F. Bowman ; Relining and Rebasing
Techniques Essentials of compete denture prosthodontics; 341-
354
• Boucher CO; the relining of complete dentures J Prosthet
Dent.1973;30;521-526
• Bowman J; relining full upper and lower dentures DCNA 1977;
21; 361-37
99. • Hansen NJ; Relining and rebasing complete dentures a
technique. DCNA 1964; 8; 693-704
• Jordan LG relining the complete maxillary denture. J
Prosthet Dent. 1972; 28; 637-641
• Koein IE, Broner AS; complete denture secondary
impression technique to minimize distortion of ridge and
border tissues. J Prosthet Dent.1985; 54; 660-664
100. • Gracia LT. Soft Liners.Dent Clin N Am 48 (2004) 709–720
• Mark E; Improving the Outcome of Denture Relining
JCDA.2007;73(7);587-591
• Christensen FT; relining techniques for complete dentures. J
Prosthet Dent. 1971; 26; 373-381
Editor's Notes
after their original construction
When residual alveolar ridges have resorbed and
When the patient cannot afford
When the construction of new dentures with accompanying series of appointments can cause
Relining is not indicated until the tissue recovers.(2nd point )
problems until accurate diagnosis and treatment of the problem has been accomplished.(tmj)
When severe osseous undercuts exist until surgical removal and healing occurs
The occlusal vertical dimensions should be satisfactory
Centric occlusion should coincide with centric relation an error is allowable if it is so slight as to be correctable
The patient’s appearance must be acceptable to the patient and dentist. The size, shape, shades and arrangement of artificial teeth must be satisfactory.
Excessive hypertrophic tissue should be surgically removed. The dentures can be used as a surgical splint
Daily massage of the soft tissue is helpful for stimulate their blood supply
The principal pitfalls that must be avoided in any technique to refit a complete denture are as follows:
Multiple even contacts (maximum intercuspation) should be present in centric relation.
Heat-activated silicone is supplied as a single paste that consists of poly( dimethyl siloxane), a viscous liquid to which silica is added as a filler, and benzoyl peroxide as an initiator.
Centric relation
The wax is thoroughly softened,and tempered in a 135 O F. water bath, and the patient is instructed to close his jaws into centric relation, stopping just shy of tooth contact. The attempt is to develop equalized minimal pressure on the soft tissue, and the record should be remade until none of the cusps has penetrated the record. This wax or modeling compound interocclusal record is left intact on the teeth for most of the relining procedure.
A large part of the middle of the palatal portion of the maxillary denture is removed for visibility in positioning the maxillary denture during the impression making.
The premade interocclusal record helps to position the dentures during the impression making and to orient the dentures on the articulator.
The two-step impression technique will reduce the possibility of moving the maxillary denture forward during the final impression making.
forward is still a major problem.
that the patient can close on several times without the possibility of damaging the record.
This technique does not suggest any solution for difficulties of relining both dentures at the same time
The perforations will decrease the pressure inside the denture during the impression-making procedure, thereby preventing displacement of maxillary denture.
The existing centric occlusion (intercuspation) is used as a means to seat the mandibular denture during the secondary impression. The occlusion is corrected during the establishment of a new occlusal vertical dimension.
without utilizing the existing centric occlusion.
trays for making the secondary impressions.
After the maxillary and mandibular impressions are made, a new centric relation record is accomplished. All of this is done in one appointment
Denture:- A posterior palatal seal is formed in modeling compound on the maxillary denture before any other changes are made on the tissue side of the den rare.
One millimeter of space is provided inside the denture for the new impression material.
The borders are shortened 1 mm to allow space for the impression material to form a new border.
Handel is formed over the lower anterior teeth facilitates handling the denture when it is carried to the mouth.
material is suggested with the following technique: “Exactly 15 seconds after the denture has been placed in the mouth, the patient is asked to pull his upper lip down and to open his mouth wide. These actions mold the impression material over the border of the denture.” The upper denture is laid aside until the lower impression has been made.
The special trimming of the denture and making room for the impression material will facilitate the making of a reasonable impression during the selective pressure impression technique without any occlusal interference.
(2) A separate interocclusal record using already made impressions as the recording bases will allow the operator to concentrate on recording the jaw relation.
If extensive ridge resorption & loss of vertical dimensions have occurred, 3 compound stops may be required on the impression surface of the denture to reestablish a proper occlusal relationship.
A treatment liner is next placed inside the denture. The lining material should flow evenly to cover the whole impression surface and the borders of the dentures with a thin layer.
If voids are evident they should be filled with a fresh mix of liner material
Unsupported parts of the liners may occur on the borders of the denture and this indicates that localized border molding with stick compound may be needed before the placement of a fresh mix of liner.
The patient’s mandible is guided into a retruded position, to help stabilized the denture while lining the material is settling.
Excess material is trimmed away with a hot sharp scalpel
The processed resin may be weakened by addition of a tissue conditioner.
And the patient is warned about risk of denture fracture.
Denture cleansers and other preparations may cause deterioration of tissue conditioners on a short time
When border refining is necessary, check the relations of the teeth to assure that the bases have not shifted during the process.
Excessive material is not desirable and should be avoided.
Seat the labial flange in the labial vestibule first, and then seat the posterior of the denture with a superior and slight posterior motion. Do not use excessive pressure.
It may be necessary to stabilize the maxillary denture with one hand and guide the mandible to centric relation with the other.
When both dentures are relined or impressions are made for rebasing at the same appointment,
then make
The relined impression is poured with the dental stone.(1)
The master cast is poured around the impression made by beading and boxing.(2)
This cast provides the surface against which the denture is relined by embedding it in a processing flask.(3)
The flask is warmed to soften the impression compound before opening it to remove the impression material.(4)
Separating medium is applied on the plaster and stone moulds, and heat polymerized denture base resin is packed into the mould.
The flask is then closed and clamped to ensure maintenance of occlusal vertical dimension. The acrylic is then processed.
After processing the flask is cooled slowly and the denture is retrieved from stone mould, finished and polished.
As the plaster is setting, the cast with the relined impression is placed on the wet plaster platform such that the teeth penetrate the plaster surface to a depth of 2mm and the occlusal plane is parallel to the floor.
This forms an index or key of the teeth on the plaster platform which allows repositioning of the teeth maintaining the distance and the relation with the cast.
Once the plaster platform sets additional plaster is placed on the base of the cast and it is mounted on the upper member of articulator.
When mounting sets, denture with the impression can be separated from the cast.
At this point one may elect to rebase or reline the denture. It differs only in amount of trimming of denture.
The denture base is waxed, cast, and the denture are removed from the mounting, flasked, and processed with heat-cure denture base acrylic resin.
