CAST PARTIALSPARTIAL DENTURE TIPS & TECHNIQUESFor most dentists and technicians today, the removable partialdenture has been one of the least understood prosthetic devices inmodern dentistry. Twenty-first century materials and techniqueshave made the creation of partial dentures easier and more 4reliable than ever before. Aurum Ceramic/Classic’s provenSaddle-Lock® “Hidden Clasp” cast partials eliminate visible metaldisplay without the aid of cast crowns or expensive precisionattachments. And now, with the improved handling characteristicsand advanced physical properties of the newly formulatedVitallium® 2000 and Vitallium® 2000 Plus alloys, it is possible tocreate smaller, lighter partial dentures with extraordinary strengthand superior fracture resistancewhile supplying improved aestheticsand greater patient comfort. The Materials Features and Benefits • Extraordinary strength, superior fracture resistance and smaller, lighter design applications – guaranteeing patient comfort and acceptance. • Superior fit utilizing the hidden natural mesial and distal undercut planes of the abutment teeth adjacent to the denture saddle. • Vitallium 2000 improves virtually all of the working characteristics of original Vitallium. Saddle-Lock® Vitallium® 2000 • Tensile strength of over 855 MPa’s. Utilizing the more pronounced natural Manufactured in a unique, quality- mesial and distal undercut planes of the controlled process that produces a purer • Elongation of 9% (partials adjust like abutment teeth adjacent to the denture alloy, Austenal’s new Vitallium® 2000 gold). saddle, stress is shared by the adjoining Partial Denture System provides you with • Lower Vickers hardness minimizes teeth as forces are distributed in an two premium biocompatible nickel and abrasion on opposing dentition. Coupled anterior-posterior direction. Clasp emer- berylium free chrome cobalt alloys. with yield strength of over 600 MPa’s, gence is back at the casting finishing line Exceptionally strong and lightweight, the resists permanent deformation. providing proper resiliency. The clasp alloys’ improved handling characteristics • Metal surfaces retain high luster and terminals are positioned at the end of the and advanced physical properties offers resist plaque. denture saddle, effectively locking the guaranteed strength, function and segment to the ridge. Accurate measure- superior fit. Vitallium 2000 alloys have • Partials seat quickly and easily with ment and paralleling of the planes using double the elongation value of the fingertip pressure, yet there is a strong the “Retentoscope” (a precise survey and original Vitallium, resulting in a partial resistance to dislodgement. design Instrument) ensures each abut- that permits predictable adjustments with ment tooth has a comfortable, yet unprecedented fracture resistance (adjust NOTE: See Vitallium 2000 Physical positive load. Saddle-Lock also handles like gold with no fear of deformation). Properties Comparison on page 4. inadequate retention and instability in And, they have a lower Vickers hardness free-end saddle cases. The retentive clasp making each partial less abrasive to force located in the distal undercuts opposing dentition and restorations. transmits its stabilizing effect into the loose end segment of the denture resist- ing dislodging forces during mastication.
What is the Best PossibleRemovable Partial Denture?There is no perfect removable appliance, butwe can meet as closely as possible thefollowing criteria:1. Restores the lost occlusal function caused by the patient’s missing teeth2. Minimizes the stress placed on abutment teeth to ensure their longevity3. Minimizes the trauma to the supporting and surrounding tissue and bone4. Self-cleaning and does not produce food entrapment areas5. Comfortable for the patient to use and wear6. Meets the particular esthetic needs of the patientBenefits of Esthetic Designs1. Esthetics: No facial display of the metal retentive clasp arms.2. Superior Retention: Normal tooth contour provides a more dependable and usable undercut on the proximal surfaces than on the facial or lingual surfaces. Impression Techniques and Tips impression extends into the retro-molar3. Gentler to Abutments: Both the rest areas of distal extension cases. placement and retention area used reduce Clinical Examination and Study C. Pour completed impressions in high stress on the abutment tooth during Model Impression strength laboratory stone to create normal functions. A. Conduct a complete clinical examination accurate Study Models within 5 minutes4. Superior Function: The retentive clasp including Periapical and Panoramic x-rays. of impression-taking. is activated to resist lift of the appliance B. Take a high quality alginate impression D. Provide an accurate interocclusal due to tacky food during chewing (e.g., Accu-Dent System 2 from Cerum record/bite registration (Futar Occlusion compression and does not transmit stress Dental Supplies Ltd.) for both maxillary from Cerum Dental Supplies or Regisil). to the tooth. and mandibular arches. The Accu-Dent E. Provide a complete prescription including5. Durability: It does not bend or torque System 2 is a unique and highly accurate usual information pertaining to patient during function. This reduces work impression system. Two irreversible and treatment plan. Send prescription, hardening and the resulting clasp hydrocolloid formulations of Syringe Gel study models and bite registration to breakage. Esthetic designs function and Tray Gel allow the most accurate Aurum Ceramic/Classic. The laboratory longer without problems. mucostatic impression imaginable. Ensure will return mounted study models and bite rims (if bite registration wafers are not sufficient) for next appointment. F. Once the dentist has approved these, take the Master Impression. Case Planning A. It is suggested that study models be sent to Aurum Ceramic/Classic for pre- planning and computerized prosthesis design to determine rest areas and any adjustments needed to dentition. B. Takes all the guesswork out of the process and virtually eliminates adjustments. C. You will be provided with a duplicate model on which a survey and design has been outlined with rest preparation suggestions highlighted in a green colour. You can request that a custom tray be provided along with the survey and design recommendation.
C. Send complete prescription, master model, opposing model, bite registration, articulator and final design to laboratory. Laboratory will return a framework for EXHIBIT 1 try-in. PATIENT Impression and Model Tips PRESENTATION Master Impression Initial Presentation to Patients Upper Arch 1. Ensure that a full mouth impression is It is important to understand the taken with all teeth and anatomical patient’s perceptions regarding remov- Lower Arch landmarks reproduced. able restorations. They simply do not 2. Impression must be fully extended understand. What we do not under- 3. If for an upper cast partial, make sure that stand, we fear and doubt. Patients doubt the palate is included in the impression. that the prosthesis will function. They fear their removable restoration will 4. If for a lower cast partial, ensure full destroy their abutment teeth because of extension of the impression including the stress or decay. With aesthetics becom- E.R.A. E.R.A. retromolar pads. ing a prerequisite for all patients, they Bite Registration refuse to accept any restoration that shows unsightly metal on the abutment 1. Ensure bite registration is taken in centric. teeth.Computerized Prosthesis Design Models Key points you can use: 1. Die stone mixed with water (NO • “Replacing your missing teeth will notClear, Graphic Communication Hardener) is recommended in a very only improve your appearance and• Completely customized computer- thick, smooth mix. A thick mix will flow the way you feel, it can prevent many generated prosthesis/restoration designs. under vibration but does not run like a other problems from occurring.” thin mix. Thickly mixed, the model is• Provides for up to 15,000 different partial • “The space left from a missing tooth harder with less chance of air bubbles. designs per arch. affects the rest of the teeth in your 2. Indication of correct thickness of mixed mouth. The surrounding teeth try to• Maintains library of all components stone: the mix does not drip or fall off fill the space by drifting, tipping or required to create prosthesis. when the spatula is inverted. rotating while the teeth in the oppo-• Can also specify tooth condition, crown, 3. IMPORTANT: After the impression is site jaw gradually move up or down clasp type, various courses of action and poured, DO NOT invert the tray onto a into the spaces left by the missing materials. stone paddy. Inverting can cause error. teeth.”• Applies one of Stress Broken, Semi-Rigid The unset stone will try to sag away from • “When your healthy teeth move or Mixed Technique methodologies. the impression. The degree of sag (if it because of missing teeth, they may• Automatically creates a recommended occurs) will not be visible to the eye, but is cause you to bite in an unnatural way. design taking every possible configura- sufficient to cause poor fit of the frame- This creates stress on your healthy tion of teeth into account. work. Instead, mound the thick stone on teeth and the surrounding bone. Left top of the tray and allow it to set. Before untreated, this condition may lead to• Generates full colour plots of design pouring the model, place Playdoh (or chil- the loss of bone or additional teeth.” alternatives for practitioner consideration dren’s modelling clay) in the tongue area and approval. • “These problems can be prevented of the lower tray to keep the stone from with a custom-designed Partial• Also excellent patient education tool to locking over the lingual flange. Denture which will replace your explain proposed treatment. missing teeth.” Preparation Requirements• All final designs stored on the system. General Principles Insertion Presentation toMaster Impression Patients • Proper tooth preparation is a must for aA. Restore the dentition where necessary. 1. Put patient at ease. successful cast partial restoration. Prepare the teeth for rests, guide planes, • Ensure there is adequate reduction for 2. Explain function of partial. occlusal room, retention, etc. as indicated by the design. interocclusal space (e.g., minimum 1 mm 3. Prepare the patient for the fact that it space for clasp clearance where frame will take them a while to adjust toB. Using high quality alginate (e.g., Accu- crosses dentition). wearing a cast partial. Dent System 2 from Cerum Dental Supplies Ltd.), take a final impression • If necessary, ensure there is adequate 4. Demonstrate cast partial insertion (NOTE: If the opposing model is preparation for rests, guide planes and and removal to patient. Patient must damaged, take a new impression of this interocclusal space as indicated by design. be able to perform this properly as well). Pour completed impression(s) in • Guide planes must be parallel and surfaces before leaving office. high strength laboratory stone within five smooth to ensure easy insertion. 5. Instruct patient in cast partial minutes of impression-taking to create management and care. final Master Model.