Shimizu et al.

Asian Pac J Dent 2013; 13: 1-4.

A resin-bonded connector with a cast bolt incorporated with anexisting adjacent pontic: a case report
Hiroshi Shimizu, DDS, PhD,a Yutaka Takahashi, DDS, PhD,a and Kenneth S. Kurtz,DDS, FACPb
aDivision of Removable Prosthodontics, Department of Oral Rehabilitation, Fukuoka Dental College,bFukuoka, Japan, and Advanced Education Program in Prosthodontics, International Program inProsthodontics, New York University College of Dentistry, New York, NY, USA
This clinical report describes the procedure to fabricate a continuous anterior-posterior fixed partial denture
incorporated with an existing adjacent pontic on a cantilever fixed partial denture using a resin-bonded connector.
The partial denture was made of silver-palladium-copper-gold alloy. The cast bolt was made of the same alloy
and inserted to gain additional mechanical retention. Consequently, a continuous five-unit fixed partial denture
was created. The continuous five-unit fixed partial denture has functioned sufficiently for more than seven years.
(Asian Pac J Dent 2013; 13: 1-4.)
Key Words: cast bolt, connector, continuous fixed partial denture, silver-palladium-copper-gold alloy

Introduction
When it is determined that one of the abutment teeth of a long-spanned fixed prosthesis cannot be conserved,
dental practitioners must dislodge the entire prosthesis, extract the tooth and then fabricate a new larger
prosthesis. However, this process requires a long treatment period, many appointments, and the cost is generally
high. If only the abutment tooth is removed with one restoration and the remaining portion of an existing fixed
prosthesis can be used as a part of the new prosthesis, the above problems of conventional large-scale treatment
can be eliminated. The present clinical report describes the procedure to fabricate a continuous fixed partial
denture incorporated with the remaining portion of cantilever fixed partial denture using a resin-bonded
connector with a custom-made cast bolt.

A combination of a silver-palladium-copper-gold alloy, athione-phosphate metal conditioner, and 4-META/MMA-TBB resin were used.1

Case Report
A 60-year-old man was seen with the chief complaint of occlusal pain and pus coming out of the leftmaxillary second premolar, which served as one of the abutment teeth of a posterior fixed partial denture andreplaced the missing first molar. Examination revealed that the root of the second premolar had fractured, andconservative treatment appeared to be impossible. He agreed to the tooth extraction but did not want an implant,
which would involve surgical treatment along with a removable partial denture; he preferred the fixed prosthetictreatment.

However, he was not happy about the long treatment period.

Therefore, the addition of aresin-bonded connector to the two existing fixed partial dentures with minimal vital tooth reduction wasproposed, and he chose this treatment option. The posterior fixed partial denture was cut at the juncture between
the second premolar and the pontic of the first molar, and then the second premolar was extracted. The
remaining posterior cantilever fixed partial denture was left as it was.
After allowing the wound to heal for two months, the treatment was restarted. The first premolar was vitaland was one of the abutment teeth of the existing anterior fixed partial denture replacing the missing canine. The
preparation along the palatal and buccal surfaces of the first premolar up to the central buccal and palatal

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Asian Pac J Dent 2013; 13: 1-4.

grooves, respectively, was made with an occlusal strut approach involving minimal preparation.2 For the ponticof the remaining posterior cantilever fixed partial denture, reduction of the palatal and buccal surfaces up to thecentral buccal and palatal grooves was made with an occlusal strut approach and retentive hole (Fig. 1).

123456Fig. 1. Missing left maxillary second premolar andpreparation of the first premolar and theexisting adjacent pontic of cantilever
posterior fixed partial denture
Fig. 2. Definitive cast showing the preparations
Fig. 3. Resin-bonded connector on the definitive
cast
Fig. 4. Seated resin-bonded connector
Fig. 5. Pattern for a cast bolt using burnable plastic
rod and inlay wax
Fig. 6. Cast bolt tried-in
Fig. 7. Completed fixed partial denture incorporatedwith the existing denture blends well72

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Asian Pac J Dent 2013; 13: 1-4.

A master impression was made using a reversible hydrocolloid (Aromaloid, GC Corp., Tokyo, Japan), and adefinitive cast was formed using high-strength stone (Fujirock, GC Corp.) (Fig. 2).
fabricated, sprued, and invested into a cristobalite mold material.

A wax pattern was

A silver-palladium-copper-gold alloy(Castwell M.C. 12, G-C Corp.) was cast in the mold by means of a centrifugal casting machine. A resin-bonded
connector was fabricated with an indirect composite material (Solidex, Shofu Inc., Kyoto, Japan) (Fig. 3).
It was tried-in, adjusted and polished, and the intaglio surface to be bonded was air-abraded with 50 µmgrain-sized aluminum oxide (Aluminous Powder WA 360, Pana Heraeus Dental Inc., Osaka, Japan) using a gritblaster (DUOSTAR Z2, BEGO, Bremen, Germany). Just before insertion, a thione-phosphate metal conditioner(Alloy Primer, Kuraray Medical Inc., Tokyo, Japan) was applied to the intaglio surfaces of the retainers. The
first premolar was cleaned and etched with 65% phosphoric acid, whereas the prepared metal surface of thepontic was air-abraded with 50 µm aluminum oxide using a portable air-abrader (Microetchblow, Morimura
Dental Co., Tokyo, Japan), and the same metal conditioner was applied. The resin-bonded connector was thenseated with an adhesive luting agent (Super-Bond C&B Ivory, Sun Medical Co., Ltd., Moriyama, Japan) (Fig. 4).
The next day, a horizontal hole was palatobuccally prepared on the palatal surface of the connector of the firstmolar, and the pattern for a cast bolt was made directly using a combination of a burnable plastic rod and inlay
wax (Inlay wax medium, GC Corp.). The pattern was sprued (Fig. 5), invested and cast using the same alloy.
The bolt was tried-in, air abraded, treated with the same metal conditioner, and cemented with a dual cure-type
self-adhesive cement (Clearfil SA luting, Kuraray Medical Inc.) (Fig. 6) using a portable light-curing unit
(G-Light Prima, GC Corp.). The surface of the bolt was smoothed and polished (Fig. 7). The patient thenfollowed a regular check-up program every 6 months. The continuous five-unit fixed partial denture has
functioned sufficiently for more than seven years, and the patient has been satisfied with the results.

Discussion
The advantages of the present procedure are 1) relief of the patient’s discomfort due to the removal of theexisting fixed prosthesis, 2) time savings, 3) simplified laboratory work, and 4) reduction in the amount and costof materials required. The design of the resin-bonded connector described in the present report is similar to thatof a posterior resin-bonded fixed partial denture, which is composed of a groove, plate, and strut and involves
minimal preparation to receive the retainer.2 A long-term follow-up study indicated that the mobility of theabutment teeth was one of the decisive negative prognostic factors for successful resin-bonded prostheses.3 In
the present situation, the pontic of the remaining posterior cantilever fixed partial denture was equivalent to amobile tooth. Therefore, additional retentive preparation forms are definitely required. The cast bolt should befabricated and inserted with a dual-cure type self-adhesive cement4 because of its rapid hardening, and thecement must be sufficiently set just before grinding and polishing the bolt.
V Primer,1,5-7 and Metaltite,7 which are the thione metal conditioners used for noble metal alloys as well as
Alloy primer1 applied in the present case and other situations,8,9 can also be used with a combination of asilver-palladium-copper-gold alloy and 4-META/MMA-TBB resin.

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Asian Pac J Dent 2013; 13: 1-4.

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Correspondence to:Dr. Hiroshi Shimizu
Division of Removable Prosthodontics, Department of Oral Rehabilitation, Fukuoka Dental College
2-15-1 Tamura Sawara-ku, Fukuoka 814-0193, Japan
Fax: +81-92-801-0513 E-mail: simizuh1@college.fdcnet.ac.jp
Accepted January 31, 2013.
Copyright ©2013 by the Asian Pacific Journal of Dentistry.
Online ISSN 2185-3487, Print ISSN 2185-3479

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