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Proud members of D.I.A.C. since 1992 Dental
Industry Association of Canada
dent-line of canada inc.,
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Volume 7 Issue 1 Winter 2003 A BULLETIN DEALING WITH ISSUES FOR DENTAL HEALTH PROFESSIONALS Exchangeable Stud Extends Retention Life  Precision
attachments such as Dalbo / Swiss Mini, Ceka / Swiss Anchor or Split
Roach Ball and many other precision attachments have their limitations.
A recent study by M. Wichmann, DDS and W. Kunz, DDS “Wear
Study of
Attachments “Journal of Prosthodontics, 12 404-9, 1999 has determined
that conventional metal attachments showed significant wear and
retention loss. By contrast the plastic attachments showed only
negligible friction loss and the most consistent retention force. In
addition, replacement of the plastic inserts restored friction to the
initial manufactured retention. Furthermore the study concluded wear
induced loss of retention in attachment retained dentures poses a major
clinical problem. To counteract this unwanted effect, most
prefabricated precision attachments can be activated to restore wear
induced loss of friction. This is achieved by design elements such as
resilient metal tongues, partially or completely slotted male
components or set screws. Over time activation of these metal male
components will induce fatigue of the metal alloy followed by breakage
of the retention elements, if they have not already worn out during
daily function. The question is then how costly will it be to replace
the existing abutment restoration with the same attachment system? Or
should you consider another approach? A recent innovation by Bredent
has revolutionized attachment systems. The existing VKS- OC/SG stud
attachment has been engineered with a threaded screw and a
reversed
hex at the head of the stud, which can be rotated in or out of the
restoration when necessary. This exchangeable stud will be able to be
used vertically with the OC retention sequence or horizontally with the
SG retention sequence. The exchangeable stud will extend the life of
the restoration far beyond accepted parameters. The exchangeable stud
can be replaced intraorally when the plastic retention sequence of
green, yellow and red are exhausted. Indications for use are bilateral
removable partial dentures, implant bar supported over dentures and
root cap treatment over dentures. The exchangeable stud is made of
titanium, whereas the retaining housing is offered in platinum /
iridium or a gold, platinum/ palladium alloy. Procedures both clinical
and technical are relatively simple. In the laboratory the exchangeable
male stud and retaining housing are waxed to the abutments or bar
following the path of insertion. Using the hexagonal screw driver the
titanium stud head is rotated out of the threaded housing counter clock
wise. Prior to investing the waxed abutments or bar, the retention stud
must be replaced with the fixation pin. Colloidal Graphite is applied
on to the threads of the fixation pin before investing so as to protect
the integrity of the threaded housing as it is being held in place
during the burnout and casting procedure. Later the casting is sand
blasted and the fixation pin is turned out before porcelain application
on the crowns. In the case of the bar or root caps treatment the stud
is replaced into the housing and it is polished to a high luster with
titanium polishing paste. The yellow retention sleeve is positioned on
the stud and the model is prepared for duplication of the removable
full or partial denture. Clinically, when the retention sequence is
exhausted and the stud wears, it can be removed intraorally and
replaced into the existing abutments or bar. Then a new retention
sequence can commence. This procedure can be performed indefinitely,
provided that proper maintenance of the restoration is carried out. Source;
Peter T. Pontsa RDT. For further information contact us at
1-800-250-5111 or E-Mail: info@dent-line.com
Multisil-Soft Denture Relining System  Multisil-Soft
is a silicone denture relining material suitable for new and old
restorations that are based on polymethyl-methacrylate material. The
indicated range of usage is for cushioning of hard palate,as an over
denture during the healing phase following implant placement ,
subsequent to multiple tooth extractions and to relieve pressure areas
in the upper and lower jaw. Multisil-Soft is specifically for indirect
preparation of full or partial dentures. It is packaged in dual
cartridge auto mix format with dosing gun. Most types of
acrylic
based relining systems require messy handling procedures were as the
Multisil-Soft has flow characteristics that allow rapid processing.
When cured the material is permanently elastic and prolonged comfort of
wear is a distinctive feature. To process this material the model and
denture are placed into a reline unit. The areas of the denture to be
relined is reduced by 2 mm then a chamfer 1 mm deep is prepared in the
vestibular area 3 to 4 mm above the peripheral borders. The surface can
be cleaned with oil free air. The master model is sealed with separator
(e.g. Isoplast 54001019). Apply Multisil Primer onto all areas to
receive the material and let dry three minutes. Then apply the
Multisil-Soft uniformly and completely onto the prepared areas. At room
temperature the material can be processed in approximately three
minutes. Once the application is complete, the reline unit is closed
and curing is either carried out under atmospheric pressure or in the
pressure pot at 45â Celsius. Deflasking is carried out after
hardening
time of 15 minutes. Polymerizing in the pressure pot should be the
preferred method since it increases physical values for the
resin-silicone bonding system. When Multisil-Soft is totally cured it
exhibits exceptional wear and tear. The functional margins and
transitional zones are contoured using a scalpel or silicone bur
(S237QG65). Alternatively there are two other silicone burs that can be
used to finish other areas (S263QG60) and (S187QG23). Next apply
Multisil Soft sealing agent onto the processed silicone areas and allow
it to air dry. The sealing agent adds a permanent shine to the silicone
surface and protects against accumulation of plaque and penetration of
bacteria into the surface. Multisil-Soft has a shelf life of two years
if it is stored in the original sealed container at room temperature
under 28 C and protected against sunlight. The relined denture can be
cleaned by the patient several times a day under running water with a
tooth brush and a non abrasive soap. If an ultrasonic is used the
denture must be placed in a zip lock bag with some water in it before
being submerged in the cleaning system. Failure to do so will result in
the reline material separating from the denture. Source;
Peter T. Pontsa RDT, for additional information contact Dent-line of
Canada Inc. at 1-800-250-5111 or E-Mail: info@dent-line.com
Bredent's Diagen Turbo Grinder  The “Diagen Turbo” is the most aggressive sintered diamond effective against Procera TM, Inceram TM, and all other ceramic materials. Each stone is molded under exacting conditions determined by Bredent to extract the optimum grinding properties. Diagen Turbo diamonds cut effectively down to the last layer. The diamonds remain in their optimum cutting positions at all times, because there is a mechanical and wetting link between the porcelain bonding material and the synthetic diamonds. This is carefully proportioned to ensure maximum cutting efficiency and minimal heat so that chipping is virtually eliminated. The prolonged service life in comparison to conventional sintered diamonds provides a higher efficiency and a wider range of applications. Visit us at www.dent-line.com. for more information or call us at 1-800-250-5111 or E-Mail: info@dent-line.com
VKS Stud Replacement Kits  Over time, the VKS attachment stud may exhibit symptoms of wear, which leads to loss of retention of the denture. Customarily, the patient requires a remake of the abutment and the denture restoration. To avoid the additional costs and discomfort, the VKS attachment stud replacement has been developed. The kit is specific to gold alloys and is available to replace 1.7 mm and 2.2 mm studs. The instruments allow the worn VKS stud to be milled and threaded intraorally to a cylindrical post, over which a new titanium stud can be positioned and secured with adhesive. The procedure eliminates the need to restore the entire restoration and will extend the functional life of the prosthesis. Source; Dent-Line of Canada Inc. Creative Aesthetic with Gold Contouring Liquid  Whenever cosmetic type restorations are indicated, the aesthetics are paramount to a satisfied patient. Whether the restoration is a veneer, all ceramic or porcelain fused to metal, it should be shaped and contoured to match and co-exist with the existing natural dentition. In the situation were veneers or all ceramic restorations are processed, the restorations are divested from the mould with a Giflex diamond disc, then blasted with glass beads. When the restoration is adapted to the die, the porcelain layering can begin. The surrounding area should be insulated to prevent moisture from the porcelain from being absorbed into the die stone. The correct dentins, enamel and effect powders should be selected. A picture of the patient or a diagnostic model showing the original shape of the teeth would be a bonus. Shaping and building up of the restoration begins with the cervical layers of colored opacious dentin. The rest of the tooth is built up over the opacious dentin with the selected dentin material up to the incisal edge. The occlusal relationship is adjusted on the articulator to correct the bite. Using a smaller sized Kolinsky brush, the height of contour is layered with a dentin some what less intense in shading than the base dentin. For the application of the enamel, the incisal edge and the mesial and distal surfaces should be prepared through beveling using an appropriate carving instrument. The beveling should taper off gradually so as to avoid any noticeable joint between the body dentin and the enamel. The incisal area is layered with a combination of enamel dentin and transparent porcelains. At this point any information regarding decalcified areas or mamelon colors should be transferred to the ceramics so that it will produce the desired effects. These characteristics are then layered with transparent and enamel materials. After initial firing, the proximal contacts points are contoured and some tooth form modifications are ground with diamond instruments ( e.g. Sintered Diamonds), then enamel and transparent porcelains are added and fired again. Although the amount of shaping and contouring are kept to a minimum, the incisal edges need to be adjusted. The Bredent “Diagen Turbo” diamond grinders are ideal for contact points, shaping and contouring the overall anatomy. Aesthetically the labial surface highlights are emphasized by cutting vertical striations along the body from the neck up to the incisal edge. More characterization is also created by incorporating horizontal striations around the neck area of the restoration. Then the lingual highlights are detailed as well as determining occlusal function on the articulator. The over all appearance of the surface and tooth form is matched to the neighboring natural teeth using Bredent “Gold Contouring Liquid”. This liquid is painted over and onto the restoration and adjacent stone teeth, of the master model. It then dries to a fine gold powder and the surface and shape of the restoration can be evaluated. What happens to the eye is quite amazing, as the gold powder masks out the porcelain and die stone, the eye is not distracted by diverse color combinations and it can concentrate on concave plus convex contours and imperfections will be highlighted as a result. These imperfections or corrections of shape can then be carried out to improve tooth form by grinding or by adding more porcelain materials. The diagnostic model or picture will help finalize this exercise. The gold powder can then be removed with running water. The restoration is reinspected and then polished with diamond paste to achieve a natural appearance. Using Bredent's” Gold Contouring Liquid” enables us to focus on aesthetic contouring and shaping over conventional methods. Source; Peter T. Pontsa, RDT Technorama 2003 Dent-Line of Canada Inc. welcomes you to attend and join us at Technorama 2003. Canada's largest Dental Technical Exhibition on Friday April 5th from 1:00 PM to 9:00 PM and on Saturday April 6th from 9:00 AM to 2:30 PM. The location is at the International Plaza Hotel and Conference Centre, 655 Dixon Rd., Toronto Ontario. Attendance to the exhibit floor and the wine and cheese party is free. The Denturist Association will be conducting a seminar on Quality Assurance on Friday and Mr.Renny Challoner will lecture on laboratory management on Saturday. A silent auction will also be held benefiting the Children's Wish Foundation. Hotel reservations can be made by calling 1-800-668-3656. Technorama is presented annually by the members of the Dental Industry Association of Canada for lab technicians, assistants, denturists, lab owners and students. Trade News Announcement: Milling Courses
The Dent-liner; Vol. 7, No. 1 Subscription Rates: |
