M. G. PIANCINO*, D. FARINA†, F. TALPONE*, T. CASTROFLORIO*, G. GASSINO‡,
V. MARGARINO‡ & P. BRACCO* *Cattedra di Ortognatodonzia e Gnatologia-funzione masticatoria, Universita` degli
Studi di Torino, Torino, Italy, †Department of Health Science and Technology, Center for Sensory-Motor Interaction (SMI), Aalborg University,
Aalborg, Denmark and ‡Servizio di Riabilitazione Orele, Maxillo-facciale, Universita` degli Studi di Torino
SUMMARY The aim of this study was to investigate
the adaptation process of masticatory patterns to a
new complete denture in edentulous subjects. For
this purpose, muscle activity and kinematic parameters
of the chewing pattern were simultaneously
assessed in seven patients with complete maxillary
and mandibular denture. The patients were analysed
(i) with the old denture, (ii) with the new
denture at the delivery, (iii) after 1 month and
(iv) after 3 months from the delivery of the new
denture. Surface electromyographic (EMG) signals
were recorded from the masseter and temporalis
anterior muscles of both sides and jaw movements
were tracked measuring the motion of a tiny magnet
attached at the lower inter-incisor point. The subjects
were asked to chew a bolus on the right and
left side. At the delivery of the new denture, peak
EMG amplitude of the masseter of the side of the
bolus was lower than with the old denture and the
masseters of the two sides showed the same intensity
of EMG activity, contrary to the case with the
old denture. EMG amplitude and asymmetry of the
two masseter activities returned as with the old
denture in 3 months. The EMG activity in the
temporalis anterior was larger with the old denture
than in the other conditions. The chewing cycle
width and lateral excursion decreased at the delivery
of the new denture and recovered after
3 months.
KEYWORDS: surface electromyography, chewing, jaw
muscles
Accepted for publication 20 March 2005
Introduction
Mastication is a highly coordinated neuromuscular
function involving fast effective movements of the
jaw and continuous modulation of force (1). It is
characterized by ritmicity and a diversity of patterns of
jaw, tongue and facial movements, that vary depending
on the species and food ingested (2). The commands
underlying the basic rhythmical movements of mastication
are generated centrally but those involving
adaptive control are regulated by afferent information,
particularly related to oral-facial kinestetic inputs (2).
The loss of teeth determines important changes in
the masticatory system, which affect bone, oral mucosa
and muscles. The alveolar bone tends to resorb, the
formation of new bone is loosen, and the overlying
mucosa presents a decreased number of receptors, thus
the afferent inputs are reduced (3, 4). Sensory receptors,
such as muscle spindles, periodontal and intradental
pressoreceptors strongly influence the activity of motor
neurons and, thus, muscle control (5, 6). Much of
the integration of sensory feedback with the centrally
generated drive occurs at the level of the premotoneurons
in the nucleus reticularis parvocellularis and in the
mesencephalic trigeminal nucleus and adjacent nuclei
(5). Most of the cells in these nuclei have mucosal
receptive fields and respond to pressure applied to the
teeth, or to stretch of the jaw muscles (5).
In edentulous subjects sensory feedback is altered. In
these patients, the masticatory cycle amplitude and
ª 2005 Blackwell Publishing Ltd 863
Journal of Oral Rehabilitation 2005 32; 863–870
efficiency, and the masticatory force are smaller in
comparison with dentate subjects. Moreover, both
opening and closing velocity of masticatory cycles are
reduced, while the occlusal pause is longer (7, 8).
The change of denture determines a modification of
the peripheral information, with a need of adaptation of
the motor control strategy. Mastication is realized by
modulating the activity of the elevator muscles to
preserve the chewing pattern (9, 10). The investigation
of the adaptation process to a new denture is relevant to
understand the control of masticatory muscles and may
provide essential information for the diagnosis of
dysfunctions of the masticatory system (11, 12). The
analysis of electromyographic (EMG) activity and kinetic
of the movement provides an insight into the motor
control system (13).
Although after rehabilitation with a new denture
EMG parameters usually approach those observed in
dentate subjects, this is not observed in specific cases
(7, 8). In this context, many factors play a role, such as
age, gender, number of years of being edentulous, oral
conditions, denture mobility and subjective experience
wearing dentures (14). The poor fit and the lack of
stability of the full denture clearly affects the masticatory
function (15).
To provide further insight into the adaptation of
mastication to a new complete denture in edentulous
subjects, we planned a longitudinal study for the
simultaneous evaluation of jaw muscle activity
(through EMG) and functional outcome (kinematic
parameters of the chewing pattern) in patients with
complete denture. The subjects were thus analysed in
four experimental sessions: (i) with the old denture
(used for at least 2 years), (ii) with the new denture at
the delivery, (iii) after 1 month and (iv) after 3 months
from the delivery of the new denture.
Methods
Subjects
Seven subjects (four males; age, mean ± s.d.,
63Æ2 ± 6Æ9 years) wearing complete maxillary and mandibular
denture, referring to the School of Dentistry,
Prosthodontic Department, University of Turin, were
selected for the study out of 62 patients. Patients were
recruited with the following inclusion criteria: (i) full
denture wearers (maxillary and mandibular) since at
least 2 years; (ii) stable denture and (iii) good cooperativeness
in the experiment. The exclusion criteria were
the presence of (i) significant medical problems; (ii) soft
and hard tissue oral pathologic disorders; (iii) mandibular
dysfunction and (iv) any pathology affecting
mandibular movements.
New dentures were manufactured with the structural
standards used by the School of Dentistry, University of
Turin. They were designed considering the residual
structures for each subject. Posterior teeth mounting
was executed with Gerber’s technique (multilocally and
independently stable) (16, 17). With this technique,
each tooth, if functionally stressed, transmits forces to
the respective osteo-mucosal support so that the denture
is not displaced. Moreover, the denture prevents
displacement independently from retention forces.
Teeth are mounted estimating the neutral zone,
i.e. the area where tongue forces, working outward,
are neutralized by cheek and lip forces, working inward.
Finally, the freedom in centric technique (17) was used;
it consists in mounting a short radius pestle (maxillary
teeth) and a long radius mortar (mandibular teeth).
Experimental procedures
The same experimental procedure was repeated (i) with
the old denture, (ii) with the new denture at the
delivery, (iii) after 1 month and (iv) after 3 months
from the delivery of the new denture. In each experimental
session, the subjects were asked to chew a soft
bolus (20 · 20 · 20 mm size), which was prepared
with the procedure described in (18). Briefly, 180 g of
cooking gelatine were dissolved in 1 L of water and the
mix was put in a container and warmed up to 60 _C.
10 mg of fucsin were dissolved into 20 mL of water and
then added to the gelatine; the mix was put in a steel
mould and solidified in about 2 h at room temperature.
Pieces of 20 · 20 · 20 mm size were cut and put in a
solution of formalin and water for 24 h before their use.
During the test, the subjects sat comfortably on a
chair with the EMG electrodes placed over the masseter
and temporalis anterior muscles of the two sides, as
described below. They were asked to fix a target on the
wall, 90 cm far, to avoid lateral movements of the head.
The measures were performed in a silent and comfortable
environment. Each recording began with the jaws
with the largest number of teeth in contact (19). The
subjects were asked to find this starting position by
lightly tapping their opposing teeth together and then
clenching. They were asked to hold this position with
864 M. G . P I A N C I N O et al.
ª 2005 Blackwell Publishing Ltd, Journal of Oral Rehabilitation 32; 863–870
the test bolus on the tongue, prior to start the
recording. Each test consisted in a 10-s long chewing.
The chewing was on the right and left side. The test was
repeated six times for each side, for a total of
12 mastications.
Surface EMG recordings
Surface EMG signals were recorded with an eightchannel
electromyograph (model EM2; bandwidth
45–430 Hz per channel)*, which is part of the K6-I
WIN Diagnostic System (20). The relative large highpass
frequency in EMG recordings was selected to
reduce low-frequency movement artefacts. Two electrodes
(Duotrode silver/silver chloride EMG electrodes)*
were located on the masseter and temporalis muscles of
both sides, according to the anatomical landmarks
described by Castroflorio et al. (21), with an interelectrode
distance of 20 mm. This electrode arrangement
and placement provides small sensitivity to
electrode displacements and, thus, good repeatability
of EMG variables (21). Before electrode placement, the
skin was slightly abraded with abrasive paste and
cleaned with ethanol.
Kinematic parameters of the chewing cycle
The mandibular motion was measured with a kinesiograph
(K6-I)* (Fig. 1). The instrument measures jaw
movements with an accuracy of 0.1 mm. Multiple
sensors (Hall effect) in a light weight (four ounce) array
track the motion of a tiny magnet attached at the lower
inter-incisor point. The magnet was put at the level of
the vestibular resin flange on the mandibular denture,
in correspondence to the central incisors, in the fornix
deepest point, without interference with the teeth. The
magnet was fixed to the denture by adhesive paste and
was encircled with dental wax to reduce asperities and
avoid pain in the mandibular lip mucosa. Before
removing the magnet, an impression, with silicone
material, of the mandibular denture frontal area was
taken. Thus, the magnet position could be reproduced
in subsequent experimental sessions. The kinesiograph
was interfaced with a computer for data storage and
subsequent analysis. Kinematic and EMG data were
collected simultaneously.
Signal analysis
The envelope of the surface EMG was computed by
signal rectification and low-pass filtering. The maximum
value of the envelope was used as an index of
muscle activity. The raw kinematic data were analysed
with a custom-made software (Chewing Cycles Analyser,
CCA)† and based on the approximation of the
chewing cycle by Bezier curves. The mean cycle (on
three dimensions) of the set of mastications in each test
was used for further analysis. The first cycle, during
which the bolus was transferred from the tongue to the
dental arches, was excluded from the computation of
the mean cycle. Other cycles were excluded if they
presented at least one of the following characteristics:
(i) minimum opening smaller than 4 mm; (ii) duration
shorter than 300 ms; or (iii) vertical opening smaller
than 3 mm.
From the mean cycle, the following variables were
extracted: (i) pattern width; (ii) sagittal angle (19);
Fig. 1. Experimental set-up. The kinesiograph K6 and the surface
electromyographic electrodes are mounted on the subject.
*Myotronics Research Inc., Tukwila, WA, USA. †University of Torino, Torino, Italy.
EMG IN COMPLETE DENTURE WEARERS 865
ª 2005 Blackwell Publishing Ltd, Journal of Oral Rehabilitation 32; 863–870
(iii) vertical range (9, 22); (iv) lateral excursion;
(v) angulation of the frontal pathway; (vi) maximum
opening velocity and (vii) maximum closing velocity.
Statistical analysis
Data were analysed using three- and four-way repeated
measures analysis of variance (ANOVA). Significant
interactions were followed by post hoc Student–Newman–
Keuls (SNK) pair-wise comparisons. The alphalevel
for statistical significance was set to P £ 0Æ05. Data
are presented as mean ± s.e.
Results
All patients answered a questionnaire in which they
indicated that after 3 months of use the new dentures
were more comfortable and efficient than the old
ones.
EMG activity
Masseter muscle. A four-way ANOVA was used to analyse
the dependence of peak EMG envelope on the following
factors and the interaction between factors: trial (six
trials for each recording configuration), side of chewing,
experimental session (old denture, new denture
when delivered, new denture after 1 month, new
denture after 3 months), and recorded side. EMG
amplitude in the masseter was not significantly affected
by any of the factors when considered independently
from each other. However, there was a significant
interaction between side of chewing and recorded side
(F ¼ 63Æ64, P < 0Æ001). EMG amplitude from the
muscle of the side of chewing was significantly higher
than that of the other side (SNK: P < 0Æ01) (Fig. 2a).
There was also a significant interaction between side of
chewing, recorded side, and experimental session
(F ¼ 3Æ55, P < 0Æ05). With the old denture, EMG
amplitude was significantly higher for the chewing side
than for the other side (SNK: P < 0Æ01) (Fig. 2a). This
did not hold when the new denture was delivered, i.e.
at the delivery of the denture there was no difference
between EMG amplitude of the two sides. The two sides
led to different EMG amplitudes only after 1 month
from the delivery (SNK: P < 0Æ05; Fig. 2a).
Comparing the different experimental sessions, EMG
amplitude was smaller at the delivery of the new
denture than with the old denture only for the side of
chewing and not for the other side (SNK: P < 0Æ05).
After 1 month, EMG amplitude did not change with
respect to delivery and was still smaller, for the side of
chewing, than the amplitude with the old denture.
After 3 months, EMG amplitude increased with respect
to 1 month (SNK: P < 0Æ05) and was not significantly
different from the amplitude recorded with the old
denture (Fig. 2a).
Temporalis anterior muscle. A four-way ANOVA (factors:
trial, side of chewing, experimental session, and recorded
side) of temporalis anterior EMG amplitude was
significant for the interaction between side of chewing
and recorded side (F ¼ 24Æ9, P < 0Æ01) and for the
interaction among the trial, side of chewing, and
experimental session (F ¼ 4Æ5, P < 0Æ05). Post hoc SNK
test revealed that the EMG activity in the side of
chewing was higher than in the other side (P < 0Æ05).
Moreover, the EMG activity of the temporalis muscle
with the old denture was higher than in all other
experimental sessions (SNK: P < 0Æ05; Fig. 2b).
Kinematic parameters
Three-way ANOVA’s were used to analyse the dependence
of kinematic parameters on the following factors
and interaction between factors: trial, side of chewing
and experimental session. Kinematic parameters for
the four recording conditions are reported in Table 1.
The pattern width was significantly affected by the
experimental session (F ¼ 3Æ6, P < 0Æ05). Pattern width
was smaller with the new denture at the delivery than
with the old denture and with the new denture after
1 month (SNK: P < 0Æ05). Pattern width was larger
after 3 months with the new denture than in all other
conditions (SNK: P < 0Æ05). Lateral excursion
depended on the experimental session (F ¼ 3Æ2,
P < 0Æ05), with larger values after 1 and 3 months
with respect to the new denture at the delivery (SNK:
P < 0Æ05). Moreover, lateral excursion was smaller at
the delivery of the new denture than with the old
denture (SNK: P < 0Æ05). The sagittal angle increased
with the new denture at the delivery with respect to
the old denture and was smaller after 3 months than
in the other conditions (ANOVA: F ¼ 3Æ2, P < 0Æ05; SNK:
P < 0Æ05). The vertical range, angulation of the
frontal pathway, maximum opening velocity, and
maximum closing velocity did not depend on any of
the factors.
Surface electromyographic
(EMG) amplitude (maximum of EMG
envelope) (mean ± s.e.) in the four
experimental sessions for the two
recorded sides of the (a) masseter and
(b) temporalis anterior muscle.
EMG IN COMPLETE DENTURE WEARERS 867
ª 2005 Blackwell Publishing Ltd, Journal of Oral Rehabilitation 32; 863–870
Discussion
In this study we monitored jaw-elevator muscle EMG
activity and kinematic parameters (chewing pattern) in
edentulous patients during chewing, before and after
the delivery of a new complete maxillary and mandibular
denture. This analysis provides indication on
muscle coordination and its functional outcome. Most
previous studies focused separately on EMG amplitude
(9, 10) or chewing pattern (7, 8).
With the old denture, EMG amplitude of the
masseter of the side of the bolus was significantly
higher than in the other side, as in dentate subjects
(23–25). This is because of the adaptation to the
established intra-oral stimuli of the old denture.
However, the masseter muscle activity of the edentulous
is lower in comparison with the activity of the
dentate subjects (23, 26) which is because of the
instability of the complete denture requiring a continuous
control of the dynamic mandibular posture
while chewing.
At the delivery of the new denture, there was no
difference between the activity of the masseter muscles
of the two sides, with a decrease in EMG amplitude for
the bolus side with respect to the condition with the old
denture. These results are in agreement with previous
work (1, 9, 10, 27, 28). The lack of habit to the new
denture may be one of the reasons for the decreased
EMG activity in the bolus side. The new intra-oral
stimuli may have also determined the reduced lateral
displacement and the decreased width of the chewing
cycle at the delivery of the new denture with respect to
the condition with the old denture. Moreover, the new
denture, made of rigid materials, likely activated nociceptive
afferents which inhibited muscular contraction
as a protective reflex (29, 30).
After 1 month of use of the new denture, EMG
amplitude was still lower than with the old denture but
the EMG activity of the masseter of the side of the bolus
was larger than that of the other side. After 3 months,
the masseter EMG amplitude was similar to that with
the old denture. At the same time, kinematic parameters
returned to similar values observed with the old
denture or to values indicating a more efficient chewing
pattern than with the old denture. Thus, adaptation to
the new denture occurred within 3 months and probably
previous experience with denture control during
mastication was re-established with the proper integration
between central drive and afferent information.
It has to be noted, however, that the activity of the
temporalis anterior muscle decreased with the new
denture and did not reach the initial value for all the
experimental sessions. Thus, muscle coordination with
the new denture was different than with the old one
even after 3 months. This probably indicates a more
efficient mandibular posture with the new denture
which required a lower activation of the anterior
temporalis muscles to control the mandibular position
during chewing.
The pattern width was larger after 3 months wearing
the new denture than with the old denture, which
indicated a better control and a better fitting of the new
denture. The masticatory cycle was also more displaced
towards the bolus side during the closing phase which
suggests that the new denture did not inhibit jaw
posturing.
Comparing the EMG and the cycle results, it appears
that the pattern changes were smaller than expected.
For example, despite large modifications in EMG
amplitude with the new denture at the delivery, the
opening and closing velocity did not decrease. Thus,
there was a reorganization of muscle coordination in
order to preserve the functional outcome with the new
denture as close as possible to the old condition (7, 8,
23). There are many degrees of freedom in the control
of mastication which allow for different solutions with
similar outcomes. The old, automated motor control
pattern needed 3 months to recover but the temporary
muscle activation strategy implemented in response to
the sudden change in afferent information allowed for a
functional output similar to the old condition. Thus,
edentulous subjects reacted to the new denture by
decreasing EMG activity of the masseter and temporalis
muscles, increasing the symmetry of the masseter
activity between sides, and inhibiting the mandibular
dynamic posture, while maintaining a similar chewing
cycle with respect to the old condition. This underlines
the importance of an integrated analysis of both
kinematics and EMG activity in the follow up of
patients with new dentures.
In conclusion, the results of this study indicated that
in edentulous subjects (i) with a denture used for
several years, the masseter of the side of the bolus is
significantly more active than that of the opposite side,
as it happens in dentate subjects; (ii) at the delivery of a
new denture, the EMG activity of the masseter of the
side of the bolus decreases and it reaches the values
with the old denture after 3 months; (iii) the activity of
868 M. G . P I A N C I N O et al.
ª 2005 Blackwell Publishing Ltd, Journal of Oral Rehabilitation 32; 863–870
the temporalis anterior decreases with the new denture
and (iv) the pattern width and lateral excursion return
to the values with the old denture (or higher) after
3 months while no changes are observed for opening
and closing velocities.
Acknowledgments
The authors are sincerely grateful to Professor Arthur
Lewin of the Department of Orthodontics, University of
the Witwatersrand, Johannesburg, for the useful discussion
and suggestions in the interpretation of the
results.
References
1. Karkazis HC, Kossioni AE. Surface EMG activity of the
masseter muscle in denture wearers during chewing of hard
and soft food. J Oral Rehabil. 1998;25:8–14.
2. Nakamura Y, Sessle GJ. Neurobiology of mastication. From
molecular to system approach. Tokyo: Elsevier Science; 1999.
3. Preti G. Load transfer, tissue reaction and oral function in
mandibular implant-retained overdentures. In: Zarb G,
Lekholm U, Albrektsson T, Tenenbaum H, eds. Aging, osteoporosis
and dental implants. Hong Kong: Quintessence Pub;
2002;161–167.
4. Pera P, Bassi F, Schierano G, Appendino P, Preti G. Implant
anchored complete mandibular denture: evaluation of masticatory
efficiency, oral function and degree of satisfaction.
J Oral Rehabil. 1998;25:462–467.
5. Lund JP, Scott G, Kolta A, Westberg GR. Role of cortical inputs
and brainstem interneuron populations in patterning mastication.
In: Nakamura Y, Sessle GJ, eds. Neurobiology of
mastication. From molecular to system approach. Tokyo:
Elsevier Science; 1999;504–514.
6. Lund J. Mastication and its control by the brain stem. Crit Rev
Oral Biol Med. 1991;2:33–64.
7. Jemt T. Chewing patterns in dentate and complete denture
wearers – recorded by light-emitting diodes. Swed Dent J.
1981;5:199–205.
8. Jemt T, Karlsson S. Mandibular movements during mastication
before and after rehabilitations with new complete
dentures recorded by light-emitting diodes. Swed Dent J.
1980;4:195–200.
9. Tallgren A, Mizutani H, Tryde G. A two-year kinesiographic
study of mandibular movement patterns in denture wearers.
J Prosthet Dent. 1989;62:594–600.
10. Tallgren A, Holden S, Lang B, Ash M. Jaw muscles activity in
complete denture wearers – a longitudinal electromyographic
study. J Prosthet Dent. 1980;44:123–132.
11. Castroflorio T, Talpone F, Deregibus A, Piancino MG, Bracco
P. Effect of a functional appliance on masticatory muscles of a
young adults suffering from muscles related TMD. J Oral
Rehabil. 2004;31:1–6.
12. Bracco P, Deregibus A, Piancino MG, Viora E, Reverdito M,
Giacosa L. Proposal of a diagnostic and tele-consulting
software for the interpretation of the craniomandibular
disorders: Clinical Real Time Windowing. Ortognat It.
2000;9:453–456.
13. Ow RK, Carlsson GE, Karlsson S. Relationship of masticatory
mandibular movements to masticatory performance of dentate
adults: a method study. J Oral Rehabil. 1998;25:821–
829.
14. Geertman M, Slagter A, Van’T Hof MA, Van Waas M, Kalk W.
Masticatory performance and chewing experience with
implant retained mandibular overdentures. J Oral Rehabil.
1999;26:7–13.
15. Fujimori T, Hirano S, Hayakawa I. Effects of a denture
adhesive on mastication functions for complete denture
wearers. J Med Dent Sci. 2002;49:151–156.
16. Beresin BE, Schiesser FJ. The neutral zone in complete and
partial venture. Chicago: Mosby Company; 1978.
17. Gerber A. Complete dentures in chewing function. Quintessence
Int. 1974;5:33–38.
18. Van Der Bilt A, Olthoff LW, Bosman F. Chewing performance
before and after rehabilitation of post-canine teeth in man.
J Dent Res. 1994;73:1677–83
19. Lewin A. Electrognathographics. An Atlas for diagnostic
procedures and interpretation. Berlin: Quintessence Pub.
Co., Inc.; 1985.
20. Jankelson B. Measurement accuracy of the mandibular
kinesiograph – a computerized study. J Prosthet Dent.
1980;44:656–666.
21. Castroflorio T, Farina D, Bottin A, Piancino MG, Bracco P,
Merletti R. Surface EMG of jaw elevator muscles: effect of
electrode location and inter-electrode distance. J Oral Rehabil.
2005;in press.
22. Wilding R, Lewin A. The determination of optimal human jaw
movements based on their association with chewing performance.
Arch Oral Biol. 1994;39:333–343.
23. Veyrune J-L, Mioche L. Complete denture wearers: EMG of
mastication and texture perception whilst eating meat. Eur J
Oral Sci. 2000;108:83–92.
24. Miyawaki S, Ohkochi N, Kawakami T, Sugimura M. Changes
in masticatory muscles activity according to food size in
experimental human mastication. J Oral Rehabil.
2001;28:778–786.
25. Bhatka R, Throckmorton GS, Wintergerst AM, Hutchins B,
Buschang PH. Bolus size and unilateral chewing cycle kinematics.
Arch Oral Biol. 2004;49:559–566.
26. Fontijn-Tekamp FA, Slagter AP, Van Der Bilt A, Van T’Hof
MA, Witter DJ, Kalk W, Jansen JA. Biting and chewing in
overdentures, full dentures, and natural dentitions. J Dent
Res. 2000;79:1519–1524.
27. Raustia AM, Salonen MA, Phytinen J. Evaluation of masticatory
muscles of edentulous patients by computed tomography
and electromyography. J Oral Rehabil. 1996;23:11–16.
28. Garret NR, Perez P, Elbert C, Kapur K. Effects of improvements
of poorly fitting dentures and new dentures on
masseter activity during chewing. J Prosthet Dent.
1996;76:394–402.
EMG IN COMPLETE DENTURE WEARERS 869
ª 2005 Blackwell Publishing Ltd, Journal of Oral Rehabilitation 32; 863–870
29. Sohn MK, Gravenielsen T, Arendt-Nielsen L, Svensson P.
Inhibition of motor unit firing during experimental muscle
pain in humans. Muscle Nerve. 2000;23:1219–1226.
30. Nergiz I, Proschel P, Niedermeier W. Incorporation and
occlusal stability of complete dentures. Dtsch Zahnarztl Z.
1992;47:818–821.
Correspondence: Dario Farina, Department of Health Science and
Technology, Center for Sensory-Motor Interaction (SMI), Aalborg
University, Fredrik Bajers Vej 7 D-3, DK-9220 Aalborg, Denmark.
E-mail: df@hst.aau.dk 870 M. G . P I A N C I N O et al.
