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FROM

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prosthodontics to effectively communicate desired information to the technician. The prominence of the canines and minor rotations or variations of incisal edge position can also be communicated with the anterior denture teeth mold and modified arrangement charts (Fig. 1) (Dentsply/ York Division, York, Pa.). A more ideal wax-up of the final tooth form results before the 2 mm cut back for tbe metal substructure. An implant abutment is particularly difficult to restore in the maxillary anterior region, because the diameter of the abutment post is only 4 mm and anterior labial and/or vertical bone loss is common. An anterior white wax-up over the metal framework at the metal try-in permits the dentist to evaluate lip support and high lip line during smiling. If the teeth appear too long, pink porcelain can be shaded to match the gingiva and the denture tooth size selected for customized tooth proportions (Figs. 2 and 3). Reprint

Fig. 3. Completed restoration

rization Con Jooste,

MChD,

in patient’s mouth.

of acrylic

resin

requests to:

DR. CARL E. MISCH 22691 MICHIGAN AVE. DEARBORN, MI 48124

denture

teeth

PhDa

University of Stellenbosch, School of Dentistry, Tygerberg, Republic of South Africa Stock artificial teeth asprovided by manufacturers have a uniformity of color and shade,inherent to their production, that doesnot impart a natural esthetic result to dentures. Methods have been developed for making acrylic resin teeth by incorporating staining and characterization to natural denture teeth.i, 2 These methods usethe molds of natural teeth to achieve the desired result. Surface stains applied to artificial teeth are of a temporary nature and the effect is soonlost in the oral environment. A procedure wasdeveloped for using internal staining of stock acrylic resin denture teeth to provide an esthetic and natural appearance.

4. Extend the initial channel thus created to simulate a surfaceof hypocalcification, cervical and interproximal staining, or a restoration. 5. Flow intensive light-curing compositeresin stains(Kulzer & Co., Wehrheim, Germany) of the desiredcolorsinto the channelswith a blunt probe, 6. When creating a check line, adapt the stain to the depth of the fissure by drawing a celluloid strip through it. 7. Evaluate these characterizations and correct them if necessarybefore curing with a white light system. The intact layer of enamel-coloredacrylic resin imparts

PROCEDUR

1. Use round burs in sizes2 to 4 and thin diamond disks to create the desired characterizations. 2. Obtain accessfrom the posterior surface of the denture teeth in the region that will be covered by heat-cured acrylic resin during processing.Use slow-rotating instruments to control the depth of these features. 3. The channelscreated in the tooth shouldjust penetrate the dentin body color without perforating the labial or interproximal surfacesof the tooth (Fig. 1). The burs or disks can be seen as greyish spots or lines when they penetrate the body color. aProfessor andDirector, Departmentof THE

JOURNAL

Dental

Prosthetics.

Fig.

10/4/26182 OF PROSTHETIC

DENTISTRY

1. Depth of characterization region. 279

TIPS

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covered with heat-cured ac:rylic resin to seal the characterization from direct contact with the oral environment so that deterioration does not take place.

REFERENCES 1. Tillman EJ. Moulding and staining THET DENT 1955;5:497-507. 2. Payne SH. Construction of custom 1975;19:333-46.

Fig. 2. Lingual

and labial

view of different

characteriza-

Reprint

Lions.

shade selection

using

a porcelain

George J. Gerdts, DDS,a and David F. Murchison,

DDSb School of Dentistry,

and Indiana

University,

anterior

teeth.

Dent

teeth. Clin

J PROS-

North

Am

requests to:

Rhein-Main

Gir Base, Germany,

denture

resin

DR. CON JOOSTE FACULTY OF DENTISTRY UNIVERSITY OF STELLENBOSCH PRIVATE BAG Xl P.O. TYGERBERG 7505 REPUBLIC OF SOUTH AFRICA

a subtle effect to the stains without the harshness of surface staining (Fig. 2). During the waxing of the denture, the check lines should be covered with a thin layer of wax on the lingual surface of the teeth. These regions should be

nomer

acrylic

shade gui

Indianapolis,

Ind.

The optical property of glass ionomer cement is poor compared with composite resins and porcelain. In addition, the shade selection system of one glass ionomer cement (Ketac-Fil, ESPE, Seefeld, West Germany) is difficult because there is no easy way to identify the shade of a given capsule and, clinically, the shade obtained is often different than the corresponding shade tab. An alternative method of shade selection using the Vita Lumin Vacuum shade guide (Vita Zahnfabrik, Bad Sackingen, West Germany) is presented. The photograph (Fig. 1) identifies the shades that Ketac-Fil cement color-coded capsules represent. A sample was made of each of the seven Ketac-Fil cement shades, varnished, allowed to set for 15 minutes, polished wet, and placed in water. One week later, the color was evaluated by use of the Vita shade guide and the Ketac-Fil

The opinions and views expressed herein are those of the authors and do not reflect the official policy or position of the department of the Air Force or the Department of Defense. BLieutenant Colonel, U.S. Air Force, DC; Assistant Base Dental Surgeon, Rhein-Main Air Base. bMajor, U.S. Air Force, DC; Fellow, Department of Dental Materials, Indiana University, School of Dentistry. 10/4/31348

280

Fig. 1. Clockwise brown,

from top: light, yellow, grey, grey-brown, and dark-grey.

FEBRUARY

1992

VOLUME

yellow-brown,

67

NUMBER

2

Characterization of acrylic resin denture teeth.

TIPS FROM OUR READERS prosthodontics to effectively communicate desired information to the technician. The prominence of the canines and minor rot...
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