Prosthodontics: Fixed and Removable Prostheses

• Prosthodontics entails fixed and removable protheses in dentistry.
• Prosthetic dentistry involves the art and science of creating artificial replacements for missing or damaged teeth.
• Protheses is a general term for any artificial bodily replacement.
• A prosthodontist focuses on the restoration and replacement of teeth.

Objectives of Prosthodontics

• Protecting teeth with lost structure due to decay/fracture.
• Restoring dental function.
• Supporting a bridge to replace a missing tooth in an edentulous area.
• Restoring implants.
• Improving esthetics and speech.
• Enhancing oral hygiene.
• Restoring occlusion.

Contraindications for Fixed Prosthodontics

• Diseased or missing supporting tissues.
• Absence of suitable abutment teeth.
• Poor patient health or oral hygiene.
• Inability to afford treatment.

Fixed Prosthodontics

• Treatments include crowns, bridges, and endosteal implants.

Types of Restorations

• Direct restorations are fabricated and completed in one visit inside the mouth.
• Indirect restorations need two or more visits, where the dentist prepares the tooth, takes an impression, and bonds/cements the received restoration.
• CAD is an abbreviation for computer assisted restoration (digital impression).

Materials for Indirect Restorations

• Gold, porcelain, all-ceramic, composite, PFM (porcelain fused to metal) and zirconia.

Partial Crowns

• Inlays and onlays.

Inlays

• An indirect restoration used inside a tooth cusp and are without cusps, similar to a filling.
• Can be made of composite, porcelain, ceramic, or gold.

Onlays

• Resembles a multisurface restoration, covers proximal and most occlusal surfaces, including cusps.
• Made of composite, porcelain, ceramic, or gold.

Indirect Veneers ("Laminates")

• These are ultra-thin ceramic shells bonded to the labial/facial surface.
• An alternative to minor orthodontics, but not for severe crowding, misaligned teeth, or malocclusion.
• Used to improve esthetics or anterior teeth affected by abrasion, erosion, stains, or enamel hyperplasia.
• The dentist prepares only the facial surface conservatively.
• Gingival retraction is placed and final impression is taken.
• Provisional coverage may be required based on tooth surface removed.
• Examples include porcelain, direct resin, indirect resin veneers.
• A spectrophotometer is used to determine the correct veneer shade.

Crowns

• An indirect, permanent, fixed restoration that covers decayed/damaged teeth.
• Improves aesthetics, protects RCT teeth, and attaches to dental implants.

Full Crowns

• Covers the entire anatomic portion of the tooth and is needed when the tooth is badly broken down.
• Examples include PFM, porcelain, ceramic, and metal crowns.

3/4 Crown

• Covers three surfaces, leaving the natural enamel of the facial surface visible.

Implant-Supported Crown

• It's an implant embedded in the bone and the crown screwed on or cemented.

Fixed Bridge

• A fixed bridge is a single appliance attached to at least two teeth on each side of the missing tooth.
• Described by the number of units.

Components of a Bridge

• Unit: The count of involved teeth.
• Pontic: The replacement for the missing tooth.
• Abutment: Support for replacement teeth.
• Connectors: Crowns soldered together.

Bridge Purpose

• Bridges restore function and appearance.
• They prevent consequences of not replacing missing teeth, like shifting.

Types of Bridges

• Implant supported bridge: surgically placed implants, abutments & pontics cemented on
• Maryland bridge (resin-bonded): pontic with wing-like extension from the mesial & distal sides
• Cantilever bridge: retained by one tooth on the same side

Overview of Crown Procedure

• Includes shade selection, preliminary impressions, tooth preparation (including buildup), gingival retraction/tissue management, and final impression/bite registration.

Shade Selection

• Shade is determined using a shade guide with natural light or a spectrophotometer.
• Shade Selection is completed while local anesthetic is freezing and is recorded.

Tooth Preparation

• The height and contour of the tooth are reduced using diamond burs to allow cast restoration to slide and resist occlusal forces.
• The reduction amount depends on the crown type.

Margin Finish

• Provides smooth junction of casting edges with tooth, including bevels, chamfer, and shoulders.

Restoration Aids for Crown

• Missing cusp/axial wall is needed for retention if the tooth is decayed.
• Core buildup, pins, prefabricated/custom cast dowel cares are involved.

Types of Buildups

• Core buildup is for vital teeth, using amalgam, composite, or reinforced glass ionomer.
• Pins are used for vital teeth to add extra strength to core buildup.
• Post and core is for endodontically treated teeth, using a core buildup to replace missing coronal tooth.
• Materials include amalgam, glass ionomer, or composite, with an added retentive pin.

Post & Core

• Prefabricated posts (titanium) fit in the root canal.
• Custom cast post and core uses an acrylic/wax pattern fabricated by a lab technician.

Gingival Retraction & Tissue Management

• This technique displaces gingival tissue away from the tooth in an apical direction.
• Temporarily widens the sulcus and controls bleeding after prep and before final impression.
  • Chemical, mechanical, or electrosurgical/laser methods are used.

Gingival Retraction Cord

• Plain, twisted, or braided, and are non-impregnated needing soaking in a hemostatic solution, or use an infuser syringe with disposable tips.

Impregnated Cord

• Controls bleeding, shrinks tissue, and comes in various thicknesses.
• It cannot be used for people with heart issues. -Alternative would be 5–10% aluminum chloride.

Retraction Cord Packing

• Needs set-up, basic set up, cord packing instrument (blunt rounded), cordially, scissors and dappen dish

Retraction Cord Packing/Removal

• Rinse and dry tooth, cut retraction cord length 1-1.5 inch and leave for 5-7 minutes
  • Use two cords on molars because of wider sulcus
• Remove cord counter clockwise.

Surgical Retraction

• Electrosurgery is used for hypertrophied tissue, where a surgical knife is used electrosurgically.

Final Impression & Bite Registration

• Light bodied material flows in detail.
• Regular and heavy bodied materials are thicker and stiffer for filling the tray.

CAM: Computer Assisted Resto

• A one-visit procedure with no provisional, no physical impression and less sensitivity (gagging).
• Can fabricate veneers, inlays, onlays, crowns, and bridges using a digital impression with reflective powder sprayed on the tooth.

Bite Registration

• Provides the lab technician a reproduction of the patient's bite and opposing arch restoration used for designing anatomic structures of the fixed prosthetic.

Techniques

• Wax-bite, polysiloxane, and zinc-oxide eugenol.

Dental Laboratory Needs

• Requires written prescription containing dentist's name, license number, address, shade selected, and type of prosthesis needed.
• Date on which material is expected to be back/lab working days may vary.

For metal or gold crown

• Impression poured using system to create master cast
• Dies made as exact replica of prepared part of tooth
• Wax pattern made for prepared tooth over the way die
• Occlusal registration used for the articulator
• Sprue attached to wax pattern
• Completed pattern placed in casting ring
• Burnout & pattern process
• Melted alloy injected into the pattern
• Casting cooled down
• Sprue removed
• Casting finished and polished

Porcelain Crown

• Porcelain build-up over metal coping
• Porcelain “baked” in porcelain furnace
• Porcelain is glazed

Provisional Coverage

• The purpose of a temp crown is provisional coverage.
• Prevents thermal shock, sensitivity, discomfort, over-eruption, shifting, maintains function and aesthetics.

Types

• Customs made chairside or laboratory-fabricated from the preliminary model
  • To avoid trauma before permanent cast, the temp crown lowered than occlusal/occlusion of rest of the teeth

Home Care Instructions/Post-Op

• Bite and chew carefully and avoid sticky foods
• When flossing, do not “pop” floss. Place below contact, pull floss through
• If provisional covering becomes loose/lost, contact the office to have recemented

Delivery Appointment (Cementation - 2nd appt)

• Local anesthetic may or may not be used
• Provisional coverage removed by scaler/spoon excavator and not thrown away
• Prepped tooth is examined, cleaned, and dried
• Restoration is then tried on to determine correct fit
  • If it doesn't fit, final impression is retaken – provisional replaced
  • if acceptable then dentist proceeds to final cementation Reasons for not fitting include cracking, temp crown pops off, or shifts (adjacent teeth shifting)

Cementation of the Final Restoration

• Postoperative instructions: prostho & supporting tissues brushed, dental floss used under the pontic and down into the sulcus

Bridge overview

• Similar to crown prep, longer appointment prep for greater than two teeth

Indications of Provisional Coverage

• Protects pulp from sensitivity, maintains periodontal health and tooth position, provides occlusal stability, protects margins and helps the patient chew

Criteria

• Esthetically acceptable, contours similar to natural tooth, smooth cervical margin, and occlusal surface aligned but lower than adjacent teeth
• Longevity of provisional coverage: 2 weeks – 1 month

Types of Provisionals

• Custom provisional: best fitting, natural looking, anterior or posterior applicable, but time consuming

• Prefabricated crowns: shell like, for anterior or posterior; polycarbonate, celluloid, aluminum/tin and stainless steel

• Polycarbonate crowns: incisor, canine & premolars; molar designs filled with composite resin, finished with bur

• Celluloid crowns: see through-shell, anterior teeth; shell filled w composite cured around tooth, contouring completed with handpiece outside of mouth

• Aluminum shells: comes in kit, used in posterior teeth, crown surface- anatomic=cusps/ non-anatomic=no cusps

• Stainless steel crowns: resto of primary posterior teeth in cases strength essential, match with tooth color isnt primary concern These crowns are trimmed/adapted with contouring pliers: cemented with high strength cement

• Resin bonded bridge - Maryland Bridge

• Custom provisional method before dentist preps the tooth

  • Use alginate impression, baseplate wax, vacuum form tray, silicone putty impression

Materials for Provisional Coverage

• Powder/liquid materials, bisacrylic composites ex. Protemp, light-polymerized

Cementation of Provisional Crown

• Troubleshooting/errors: occlusal errors, locking, marginal discrepancies, removal
• Removable prosthesis is where a patient can place it in and remove it freely
• Two types: removable partial denture and removable full denture

Factors Influencing Choice of Removable Prosthesis

• Extra & intra oral factors

Extra Oral Factors

• Mental health: Pt unable to keep prosthesis in mouth or agitated having denture, Lack of adequate OH

• Physical Health: medications affect how oral tissues tolerate pressure of a removable prosthesis, Pt. with poor health unable to manage long procedures Patient Motivation: Dentist should explore alternative tx options for esthetic cases

• Age: prosthesis for young person designed to allow growth, and strength of active patient important factor

• Dietary habits: poor nutrition can cause poor tissue response

• Social/Economic Factors: People like to have transition to dentures while not disturbing daily activities, patient needs to understand needs missing teeth to be replaced and cost major factor

• Occupation: concerned who meets the public concerning with possible change in appearance during or after the transition to partial or full dentures

• Appointment for surgery scheduled without disruption to patients social and occupational factors

Intraoral Factors

• Musculature: facial muscles provide retention and control, large tongue causes problems, facial spasms lose suction to denture
• Salivary flow: excessive salivary flow as response to new prosthesis, xerostomia makes it difficult to wear
• Residual alveolar ridge: high is good for support, resporbeduneven cause discomfort
• Oral mucosa: poorly fitting denture and altered physical health causes pressure point to develop on the tissue
• Oral habits: bruxism causes stress on ridge
• Tori/exostosis: overgrowth of bone affecting wearing denture ability

Removable Partial Denture

• Used to replace several teeth, long edentulous span and temp use in child

Considerations

• Replaces teeth for missing teeth or for pt. Who dont want a fixed bridge or implant and pt. finds it easier to maintain oral hygeine Contradictions: lack of suitable teeth, rampant caries

Advantages

• Patients self confidence and helps natural teeth to retain their position

Disadvantage

• Biting forces that may cause partial to move, patient may experience gingiva and discomfort
• Types of partial dentures: transitional flipper

Cast Denture

• Framework is metal
• Cast Metal Skeleton
• Provides support for components of the denture- covered with acrylic to stimulate appearance

Connectors

• Connect parts of denture
• Major connector= Rigid metal bar joints right/left quad framework
• Minors= attached to major connector branched

Rests

• Metal projection from framework major/minor extending to prepared tooth
• Used to control seating of prosthesis/prevent denture moving

Types of Rests

• Occlusal (posterior) Rest is of the occlusal surface. Minimizes trauma to tooth transmitting stress along the long axis of the teeth Lingual(anterior) Rest is placed on cingulum of lingual surface/ support good but visibility lacking (Rest placed on interproximal surfaces mesial and distal of both teeth connecting/adjacently would be called interproximal occlusal rest”

Retainer Clasp

• Supports, stabilizes denture, I-bar retainer: hooked, circumferential retainer

Stress Breaker

• Metal device in partial to protect abutment teeth/ distribute stresses throughout

The Denture Base

• Acrylic potion the removable appliance that replaces the gingival tissue (lookalikeish) The dentist sketches out design, dentist sends to lab to create metal framework before it goes to the base creation. Pink is added, and artificial secured within the denture

Artifical Teeth

• Saddle base part of denture that is attached to framework
• Porcelain teeth crack, are heavy
• Acrylic teeth do not produce clicking sound, lighter

Kennedy Classifications of Edentulous Arches

• Class I (bilateral edentulous areas posterior to the remaining natural teeth); Class II (unilateral edentulous area posterior to the remaining natural teeth); Class III; Class IV

Appointments

• To record everything for prosthetics
• Medical/Dental History Review
• Diagnosis For Denture And Prophylaxis Preliminary impressions (fabricate the study casts)

Appt 2; Teeth preparation; shade mold selection

• Shade; if there no anterior previous photo match

Teeth Prep

• No Anesthetic Pre
• Restorations Slightly Modified to Receive Rests Custom Stock Try to apply glue it onto the crown Final Impression Elastomateric or Posylaxine BITE

Laboratory Prescription Form

• patient name- framework design
• dentist sign, copy is placed in the clinic chart
• the metal framework, they send patient to laboratory, lab do select gingiva where wax be attached, took preps extra steps

Appointment 3rd time

• Is try-In
• metal framework comes back with a wax artificial try placed or checked in OK return for processing
• After bite you may need reflect change if done change

Appointment 4

• Is Delivery time is between 20/30 minutes seating mouth clasp are adjusted wirh pliers

Assisting in delivery/ basic articulate paper setup ,pressure indicating paste

• pressure adjust RPD clasp adjust
• pliers use Finger Pressure

patient educate

Store in moist air till use wash brush when you need do

• schedule appt
• Charting removable prosto

Appointment 5 Delivery Check.

• Few Days After Full Denture
• Denture adhesive: may require to help some cases

Full Denture

Designed to restore the function and esthetics of the natural dentition with the absence of all the teeth Considerations Contraindications (Patient is edentulous) physical, mental illness Pt is hypersensitive, not interested in replacing missing teeth.

Components

1. Denture Base; acrylic covering all support/retention
2. Flange- portion of base extending over the attach from cervical margin
3. Post Dam- (posterior palatal seal) maxillary is that the denture fits better without overhand to cover molars but more throat that folds better
4. Artificial Teeth-fabrication

The process of mand base - extends to the residual ridge with a attached mucosa down to oblique ridge and mylohyoid pad Appointment 1- Record :Updated health history ◦ Check tissue

Appointment 1 Records

• tissue halth, saliva, landmarks
• Preliminary impressions used in dentures
• Old dentures can be find too high to find alginate impressions
• The tray requires medication

Final impression

landmarks accurately produced, must not be any air bubbles Maxillary :hamular post dam tuberocities frenum Border moulding : is to Pull and Massage pt must Post Dam : have the patient say arrh Baseplate and Bite rims

Final Impression for Full Denture

• Temporarily represents with patient,
• register for and position, the space occupation

The dentist will most likely remember

1. Vertical distance is in the occlusion
2. smile line
3. preparation of wax to help connect jaw relationships

VDO/VDR

• (vertical dimension of rest/occlusion)
• Teeth section:
• shade, skin color, natural teeth flat, teeth will be given to the doctor

Appointment 4 try-in

denture fit, evaluation the denture is to be retained when the patient says f,vt,s,th ; swallowing or yawning occlusion to be with prepared wax after all tested for to final preparation the esthetics and they are seeking for

Appointment 5: Delivery

inserted to the mouth artificial teeth now in mold check for appearance testing of facial expressions chewing and speaking

• set up, with , hand piece, the doctor ,Mirror

Full Denture Surfaces

• Tissue surface- used to stimulate normal tissue contours, grooves and
• appointment 6: after surgery ; clean, schedule a recall, look for sore spots for cases to help ;DENTURE ADHESIVE CLEANSES DENTURES; NO BURN all prostheo cleanes Thoroughth RInse orally tissues

Immediate Dentures

Mainly for a max this means the denture pt. is on a procedure with compression will be extracted after THE TEETH ARE EXTRACTED & THE FABRICATED INSERTED DIRECLTY OVER Esthetics reasons Problems- intensive inserts after procedure that might come issues

Constucture Immediate; Imaging Fabricates Template surgical, looks tray OVERDENTURE Full tooth on the top; with bones, with any remaining teeeth like canines that helps more Lomg Lengths; 0nltiminumum will fit copine on top Long The tooth is greatly Implant is used to assist with stabillity or provide support from the top. the implant supportes the denture (SNAP-on-DentuRE

Denture Relining

Placing the material to restore raph after, Temporary Material:Medication Relinine

• Indications loss of retention
• DENTURE RELINEdue

Denture Repairs

• Patient have to be without 2;8 hours in ZOE (WITH DEUTURE and Patient close till the finale set

Tissue Conditioning-

Before reline can be done tissue and health restored Powder

• several times
• left to 3 weeks

dentures that replace base.

THE repair restore, fractured dentist dont need when they come.