Observation of Blood Flow on Palatal Mucosa using an Improved Probe
T.Kawaguchi, K.Hoshiai ,R.Ito, W.Fujinami,A.Otoda,Y.Tanaka,H.Nagai,M.Mitsui,andY.tanaka
Department of Removable Prosthodontics, School of Dentistry, Aichi-Gakuin University

Introduction
In order to evaluate oral health and the function of prostheses, it is important toclarify the movement of blood flow on the palatal mucosa and in the cervical region
around abutment teeth. In the past, we have observed blood flow on the palatalmucosa;1),2) ,however, the probe used to measuring blood flow has a number oflimitations and restrictions. In the present study we make use of a newly-developed
and more advanced miniature probe which can take more detailed measurements,
and we present measurements of blood-flow volume in the palate and near thecervical region of the teeth areas in which we had difficulty in measuring in the past.

Materials and Methods
The improved probe, which was used for blood-flow-volume measurement,is about
1/10 the diameter of the previous model, and it is more flexible. (Fig1)

Fig1: Comparison of improved model(φ0.17mm) with previous model(φ1.8mm)
By comparing measurements of the same part of a palate using both models, we
determined that there was no difference in the measurement accuracy.

Experiment①: To clarify blood flow volume of in the cervical region of teeth.
Subject: 8persons(3 men, 5 women) average age is 28.9 years old(±3.3y)
Points of Measurement: Three points separated by 1mm intervals, in the cervicalregion of the first molar 1mm (Fig 2)
Experiment②: To measure the blood-flow under a denture base at the time of load.
We created a model of a denture which covers occlusal surface of the maxillary molars
and palate. (Fig3)

Fig 2: Points of Measurement

Fig 3: Model of a denture

Blood flow volume was measured at the time of load. The maximum occlusal pressure
measurement was performed simultaneously.
・The right-and-left first molar and second molar section of the model was occluded.
・The thickness of the model was about 1.5mm
・The point of measurement was the mesial point, which was separated from the cervicalregion of right-and-left first molars by 1 mm.
・Load was measured in terms of continuous load and intermittent load.
Continuous load involved a maximum occlusal pressure of about 400N, on average,
Whereas intermittent load involved tapping at the rate of three times per second.
・On the right side, the denture model and mucosa became stuck, and on the left side,
the denture model and mucosa had about 1mm of relief. (Fig4)

Fig 4: The difference in how to give occlusal force

Results
In experiment①,a significant difference in the blood flow volume among the threemeasuring points was not seen. (Fig 5)

Fig 5: Blood flow volume among the three measuring points
In experiment②, in the case of relieved, rate with decreasing a blood flow volumebecomes
small clearly rather than in case of stuck. (Fig6)

Fig 6: Comparison of rate with decreasing a blood flow volume(continuous load)In case of relieved, rate with increasing a blood flow volume becomes small clearlyrather than in case of stuck. (Fig7)

Fig 7: Comparison of rate increasing a blood flow volume(intermittent load)

Discussion
In experiment①,a clear difference in three measured regions was not seen, and themesial point of measurement was the most stable. The mesial point of measurement
Was considered to be the optimal measurement point in the cervical region of the teeth.
Therfore, the mesial point of measurement was applied in the second experiment.
In experiment②, the aspect of blood-flow-volume change in the case of intermittent loadand continuous load which were measured under the conditions of occlusal pressure,showed the same tendency as the result of the past experiments under pressure.
Moreover, blood-flow-volume change in the case of intermittent load and continuous load
under the conditions with relief were clearly smaller than those under the conditions ofbeing stuck.This was the same result seen in past experiments under similar pressure
conditions.

Conclusion
The measurement of blood-flow-volume change under the conditions of occlusal
Pressure, which were difficult to perform until now, have become possible due to theuse of the improved probe. Under various conditions, our results were similar to thoseseen in past experiments1)-4) under similar conditions of pressure.
Based on our findings, we believed that the improved probe is sufficiently reliable foruse under clinical conditions. We intend to conduct further investigations into detailed
blood-flow-volume measurements under clinical conditions.

References
1. Hasegawa,N.: Studies of Dynamic Properties of the Blood Flow of the Human
Palatal Mucosa
The journal of the Japan Prosthodontic Society 45(1), 117-128, 2001
2. Okazaki,S.: Studies on the Dynamic Properties of Blood Flow in Denture-bearing
Palatal Mucosa
The journal of the Japan Prosthodontic Society 47(1), 125-134, 2003
3. Hoshiai,K. Tanaka,Y. Hasegawa,N. Kawakita,M. Fujinami,W. fujita,M. okazaki,S.
Hirai,H. Ota,I.: Experimental Observations of the Blood Flow of the Mandibular
Frontal-lingual Alveolar Mucosa
The journal of the Japan Prosthodontic Society 47(5), 797-806, 2003
4. Okada,C. Ueda, T. Sakurai, K.: Blood flow in denture-supporting maxillary mucosa
in response to simulated mastication by loading
Journal of prosthodontic research 54(4), 159-163, 2010