The combination syndrome: A literature review
Sigvard Palmqvist, LDS, Odont Dr,
a
Gunnar E. Carlsson, LDS, Odont Dr, Dr Odont hc,
b
and
Bengt O
¨wall, LDS, Odont Dr, Dr Med hc
c
School of Dentistry, University of Copenhagen, Copenhagen, Denmark; and School of Dentistry,
Go¨teborg University, Go¨teborg, Sweden
Although combination syndrome is recognized by many clinicians, documented observations seem to
be rare. The aim of this article was to critically review the literature regarding combination syndrome
to evaluate the evidence for this concept. A search of the dental literature with Medline/PubMed
through July 2002, focusing on the combination syndrome and related features, was undertaken and
combined with a hand search of older references and textbooks on removable prosthodontics.
(J Prosthet Dent 2003;90:270-5.)
Loss of bone of the anterior edentulous maxilla
when opposed by natural mandibular anterior teeth is 1
of several features of the combination syndrome. Al-
though recognized by many clinicians, documented ob-
servations seem to be rare.
The Glossary of Prosthodontic Terms
1
defines com-
bination syndrome as “the characteristic features that
occur when an edentulous maxilla is opposed by natural
mandibular anterior teeth, including loss of bone from
the anterior portion of the maxillary ridge, overgrowth
of the tuberosities, papillary hyperplasia of the hard pal-
atal mucosa, extrusion of mandibular anterior teeth, and
loss of alveolar bone and ridge height beneath the man-
dibular removable partial denture bases, also called an-
terior hyperfunction syndrome.”
Ellsworth Kelly
2
was the first person to use the term
“combination syndrome.” He followed a small group of
patients wearing a complete maxillary denture opposed
by mandibular anterior teeth and a distal extension distal
removable partial denture (RPD). Of the 6 patients fol-
lowed up for 3 years, all showed a reduction of the
anterior bone in the maxilla along with enlarged tuber-
osities. For 5 patients there was an increased bone level
of the tuberosities. Kelly
2
blamed the mandibular RPD
and the lack of a posterior seal in the maxillary denture
for these changes. He discussed “excessive bony resorp-
tion under the mandibular removable partial denture
bases” but provided no values. Kelly
2
discussed various
possibilities to avoid combination syndrome, including
extraction of the mandibular teeth, but did not advocate
this solution. Instead, he proposed using the roots of
anterior mandibular teeth to support an overdenture.
He also mentioned the option of using endodontic im-
plants to preserve questionable roots for support in the
posterior part of the mandible.
A few years later, further characteristics were added to
the combination syndrome: loss of vertical dimension of
occlusion, occlusal plane discrepancy, anterior spatial re-
positioning of the mandible, poor adaptation of the
prostheses, epulis fissuratum, and periodontal changes.
3
However, these changes are not generally associated
with combination syndrome.
In spite of his emphasis on the negative role of the
mandibular RPD, Kelly
2
wrote: “The early loss of bone
from the anterior part of the maxillary jaw is the key to
the other changes of the combination syndrome.” This
view was previously published in The American Text-
Book of Prosthetic Dentistry
4
in 1907 in the following
manner: “One of the most commonly observed cases of
this sort (localized adsorption) is that in which a full
upper plate denture is antagonized only by six or eight
lower natural teeth, there being no teeth posterior to
this point, adsorption of the alveolar process in the max-
illa in front occurring as a result of the undue pressure on
it.” Clinicians have recognized a number of the afore-
mentioned features in some patients, but documented
observations are rare. About 25 years after the publica-
tion of Kelly’s
2
article, a review of sequelae of treatment
with complete dentures argued that there was a lack of
evidence for the combination syndrome.
5
Today, ac-
cepting the principle of evidence-based dentistry, a crit-
ical review of the documentation behind the concept of
“combination syndrome” seems warranted. The aim of
this article was to evaluate the evidence for this concept.
LITERATURE REVIEW
A search of medical and dental literature through July
2002 was undertaken by use of Medline/PubMed. The
focus of the search was on combination syndrome and
related features such as alveolar bone loss, bone resorp-
tion, maxillary tuberosities, denture stomatitis, and
maxillary abnormalities, all combined with removable
partial denture variables. Along with the articles found
a
Professor emeritus, Department of Prosthetic Dentistry, University
of Copenhagen.
b
Professor emeritus, Department of Prosthetic Dentistry, Go¨ teborg
University.
c
Professor and Chair, Department of Prosthetic Dentistry, University
of Copenhagen.
270 THE JOURNAL OF PROSTHETIC DENTISTRY VOLUME 90 NUMBER 3
