A case of lower removable partial denture with dental magnetic attachment
S. Tsuda, S. Masumi, E. Makihara, T. Watanabe, T. Masumi, M. Yagi, M. Arita
Division of Occlusion and Maxillofacial Reconstruction, Department of Oral Function,
Kyushu Dental University---------------------------------------------------------------------------------------------------------Abstract
The patient was a 67-year-old female who had visited our clinic. She had complaint ofher lower removable partial denture. She was provided with a non-metal clasp lower
partial denture from a certain dental clinic. However, she could not wear it because thegingival inflammation caused by the non-metal clasps of the denture cut into hergingiva. She hoped another type of esthetical partial denture without clasps. No.45 wasdesigned as a root cap with a stud attachment and No.37 was designed as
magno-telescopic crown. As No.33 of direct abutment tooth was vital, this tooth wasdesigned as a resin-facing crown with an extracoronal dental magnetic attachment. As
for patient education after wearing the denture, in addition to explanation of cautionary
circumstances concerning dental magnetic attachment, we instructed about cleaning
method of extracorporeal attachment region of No. 33 in particular.
Because the new denture was good esthetically, and putting on and taking off and thecleaning were easy, it went to the satisfaction to a patient. The results of evaluation ofvarious functions before and after treatment were found an improvement tendency.
---------------------------------------------------------------------------------------------------------Introduction
Dental magnetic attachments are very useful for the retention of removable partial
dentures. At this time, we report on a clinical case of a lower removable partial denturewith stud, intracoronal and extracoronal dental magnetic attachments.
Clinical history
The patient was a 67-year-old female who had visited our clinic on April 17, 2014. She
had complaint of her lower removable partial denture. In 2013, she was provided with a
non-metal clasp lower partial denture for the edentulous region of Nos. 34, 35, 36, 46,and 47 from a certain dental clinic. However, she could not wear it because the gingival
inflammation caused by the non-metal clasps (Nos.33, 37,44, and 45) of the denture cut
into her gingiva. Her complaint was the gingival inflammation by the clasps regions ofthe non-metal clasp lower partial denture. She hoped another type of esthetical partial
denture without clasps (Fig.1).

Fig.1 Intraoral findings without the lower partial denture (May 15, 2014)
Treatment procedure
As No. 45 and 37 were non-vital direct abutment teeth, a magnotelescopic crown wasdesigned for No. 37 (Figs.2,3). As No. 33 was a vital direct abutment tooth, aresin-facing crown with an extracoronal dental magnetic attachment was designed forthis tooth (Fig.4). Dental magnetic attachments (GIGAUS C600®; GC Corporation,Tokyo, Japan) were used as retainers in all three abutments. After fixing inner crowns ofNo. 37 and No. 45 with adhesive resin cement, a removable partial denture wasfabricated by the conventional method (Figs.5, 6).

Fig.2 A magnotelescopic inner crown and a full metal outer crown on No. 37

Fig.3 A magnotelescopic inner crown and a resin-facing outer crown on No. 45

Fig.4 A resin-facing crown with an extracoronal dental magnetic attachment on No. 33

Fig.5 Finished crowns

Fig.6 Wax denture

At the try-in of these crowns and a wax denture, the patient complained about the outercrown of No. 45. She refused to see the metal color of the occlusal surface.
Therefore, we decided to use the inner crown of No. 45 as the root cap of anoverdenture (Fig.7).

Fig.7 Root cap with a keeper of No.45
Finished partial denture was set on March 10, 2015 (Fig.8~10). As for patient
education after wearing the denture, in addition to explanation of cautionary
circumstances concerning dental magnetic attachment, we instructed about cleaning
method of extracorporeal attachment region of No. 33 in particular.

Fig.8 Finished denture (August 12, 2014)
Function evaluation
Table 1 shows the results of evaluation of various functions before and after treatment.
Maximum occlusal force using the Dental PrescaleⓇ was 221.5 N before Tx, 424.2 N
after Tx. Mastication score for chewing ability by the amount of glucose elution using
Gumi-jellyⓇ was 47 mg / dl before Tx, 228 mg / dl after Tx. Mastication score was 39.7
before Tx, 49.7 after Tx. In Oral QOL evaluation, OHIP-J14 score showed 30 beforeTX, 18 after Tx and GOHAI score showed 29 before Tx, 51 after Tx. The results
showed that all items of functional evaluation were found an improvement tendency.

Table 1 Evaluation of various functions
Prognostic process
As for the periodontal basic examination and the tooth mobility test conducted on
November 7, 2017, it was almost possible to clean the patient herself because thesescores of all residual teeth were unchanged before treatment. In addition, problems were
not observed in denture base fitness test and occlusal examination, and it seemed that
this lower removable partial denture functioned well.
ConclusionBecause the new lower removable partial denture in which the dental magnetic
attachment is applied as stud, intracoronal, and extracoronal attachment was good
esthetically, and putting on and taking off and the cleaning were easy, it went to thesatisfaction to a patient. From the post treatment evaluation, it was able to confirm
improvement of the oral QOL concerned.
Regarding this report, there is no conflict of interest among all authors.

Evaluation items

Before Tx

After Tx

221.5

424.2

147228Mastication score

39.7

49.7

OHIP1430

18

GOHAI

2951Occulusal force（Dental prescale：N）
Chewing ability（Elution volume of glucose
mg/dL）