The
bridge sectioning attachment from Bredent can be utilized to anticipate
future complications if a retaining abutments fails. During the treatment
planning phase of restorative dentistry a positive case can be made for
the use of one attachment with two objectives. One, the bridge sectioning
attachment is made of a gold alloy male attachment that comes with a closing
ring and a titanium screw that enables the dental technologist to assemble
a multiple unit segmented bridge. Two, if in the future the abutment distal
to the attachment fails and has to be extracted, then the bridge sectioning
attachment from the original bridge can be utilized to accept a Vario Soft
3 female attachment that is incorporated in a new removable cast partial.
Therefore forward thinking can help in salvaging existing crown and bridge
work which can save time and which will not burden the patient financially
or cause the inconvenience of excessive appointments. The dental
technologist will prepare the master models and dies from an accurate
full arch impression, then determine the path of insertion. This attachment
compensates for non-paralellism of abutment retainers as well as segmenting
bridges. Wax the crown patterns and then place the male in a surveyor with
paralleling instrument and position it on the master model. Males should
follow the path of insertion and should be positioned over the crest of
the ridge. Following the standards of practice, cast and trim the crowns
and check proper seating of the crown attachment assembly. After applying
the porcelain,the bridge sectioning attachment is polished to a high lustre.
Next, fix the closing ring with the titanium screw and cover with modeling
resin. The rest of the bridge is waxed up around the modeling resin in
order to incorporate the pontic and molar abutments. Using a screwdriver,
the titanium screw is removed and set aside for final assembly. The wax
up is sprued, cast and finished to the standards of practice. Then, the
segmented bridge is assembled, cemented and fixed in place with the titanium
screw. After many years, if the molar abutment fails, the bridge can be
disassembled and the molar extracted. When the ridge is healed, the existing
crowns and attachment will be suitable for a new cast partial utilizing
the Vario Soft 3 inserts. Bredent’s extra coronal friction grip slide attachments
are adjustable by three different plastic inserts. There is no need for
a milled bracing arm support since the stress breaker is already integrated
into the overall attachment design, providing the opportunity for the patient
to practice good oral hygiene. Patients that have limited manual dexterity
when removing and inserting the prosthesis will find that the insertion
and removal of extracoronal precision attachments are easier to handle.
Also, extracoronal precision attachments are normally resilient and allow
for free movement of the prosthesis in order to distribute potentially
destructive forces or loads away from abutments to supportive bone and
tissue. Three characteristic movements are defined as functional; (i) Hinge;
(ii) Vertical and (iii) Rotational. The female retention sleeve can easily
be removed with a pointed instrument and a new one replaced effortlessly
with the insertion tool. The cast partial can also be rebased utilizing
standard techniques. This scenario indicates that the bridge sectioning
attachment is an acceptable option for forward thinking treatment planning.
Source;
Peter T. Pontsa RDT. For further information contact us at 1-800-250-5111
or e-mail us at info@dent-line.com
|
Master-Sep is one of the leading separating mediums in the market today. It is excellent for separating plaster from die stone. It seals the pores of the die stone, this in turn forms a tough protective coating that creates a smooth surface which gives excellent separation. The smooth flow of stone accurately duplicates every detail of the surface and gives a cleaner breakout thus making Master-Sep a perfect insulator and separator between the dental arch and the model base. For further information or pricing call us at 1-800-250-5111. Source; Dent-Line of Canada Inc. For more information and pricing call us at 1-800-250-5111 or e-mail us at info@dent-line.com |
The
fabrication of dentures is both a science and an art form. The anatomy
of aesthetics can be defined as the way in which teeth are to be replaced
and is critical to any major transition from natural to artificial teeth.
An average patient’s concerns about appearance, aesthetics and how they
look to others is the single most important outcome when fabricating complete
dentures. Ideally the basic objective is not just to restore missing
teeth aesthetically, but to restore the complete person to a healthy and
happy individual. There are a number of contributing factors that
should be reviewed starting with “naturalness”. Elements that influence
naturalness are position, dimension, alignment, form and shade.
Position: Tooth position is a bio-mechanical exercise that dictates lip support and determines the firmness of muscle tone for facial muscle activity.
Dimension: The clinical practicioner must carefully explain and guide the patient into recognizing there is a harmonious relationship between the size of anterior teeth and the size of the face. Long teeth create at toothy appearance, small teeth on the other hand shows excessive pink gingival. Scientific investigation indicates that the upper central should be one sixteenth the facial width for an optimum pleasing appearance. Individual studies indicate that stock teeth may be too uniform and it would be prudent to select central, laterals and cuspids individually rather than from the carded set provided by some tooth manufacturers.
Shade: Consider the patient’s age and complexion and select teeth with several shades to give each tooth a distinctive colour and texture. The closer an object is to the eye, the lighter it seems. Therefore, professional guidance is necessary to provide the patient with a tentative colour selection and get final acceptance at the try-in stage.
Form: There is clinical evidence to indicate that harmony between tooth form and the shape of the face is the exception and not the rule. The system of classifying faces as square tapering and avoid the corresponding carded tooth system attributed to it, may be easy to use and is widely accepted by the dental profession, however, it has no aesthetic merit or scientific basis. Since there is a lack of natural standardization and the fact the edentulous arches are changing due to tooth removal, surgery and restoration, mold selection whether square tapered or avoid cannot be selected by the from of the residual ridge. According to A. Nelson, the unchanging from of the central position of the palatal vault is the most reliable clue to the original from of the arch. Therefore, correct alignment is far more important than correct mold of tooth for the patient.
Alignment: Arrangement is the most dominating factor related to teeth and their aesthetic influence. The only correct tooth position is where teeth were in nature. Start with the maxillary centrals which are always in front of and on either side of the incisive papilla. Don’t position upper anterior teeth on top of the ridge crest since it will cause facial functional loss. Also, analyze both the vertical tooth position and the labio- lingual position while establishing phonetics. The patient’s old dentures provide a lot of information or a photograph showing the natural teeth in a smile is also welcome. Alignment in relating teeth in their long axis or breaking their alignment follow examples found in natural teeth. From studying natural dentition we can conclude there is a definite relation between the form of the maxillary arch and the alignment form of the upper anterior teeth. The arch then indicates the alignment of the natural teeth.
Final Waxing: the polished surface area of a complete denture
influences retention as well as aesthetics. The wax around the teeth
should indicate the form of the gingival tissues. Labial surface
fullness is desirable without altering the original borders. The lower
denture lingual surface should be concave to provide a resting
place for the tongue. Some festooning can create a natural look.
There is no fool proof formula for achieving a perfect result, however,
each clinician following accepted standards of practice can ensure patient
satisfaction and make this experience more enjoyable and rewarding for
all concerned. Source; Peter T. Pontsa RDT, for additional
information contact Dent-line of Canada Inc. at
1-800-250-5111 or 519-942-9315.
