The Periotest M is a measuring device for use in dental practices
and is designed for the
following range of applications:
- Implants: Assessment of the osseointegration of dental implants
- Natural teeth: Diagnosis and assessment of periodontopathies,
assessment of
the occlusal load and control of the treatment’s progress
The Periotest’s scale ranges from -8 to +50. The lower the Periotest value, the higher is the stability / damping effect of the test object (tooth or implant).
Assessment of the osseointegration of dental implants
Nowadays there are many implant systems which are in use. The Periotest
M unit is able to take measurements on all of them. Moreover, measurements
can be made at all stages of the implant process: directly after implantation,
to measure primary stability, following the healing phase to determine
that the required degree of osseointegration has taken place to enable
pressure to be applied to the implant, and following completion of
the prosthetic, to enable any negative developments to be recognised
at an early stage.
As a result of the different implant systems and the existence of varying clinical conditions with individual patients, it is only possible to present guide values here. These show which Periotest value indicate good osseointegration and which are insufficient for withstanding pressure on the implant.
| Periotest Value Range | Interpretation |
| -8 to 0 | Good
osseointegration; the implant is well integrated and pressure can be applied to it |
| +1 to +9 | A
clinical examination is required: the application of pressure on the implant is generally not (yet) possible |
| +10 to +50 | Osseointegration
is insufficient and no pressure may be allowed to act on the implant |
On the whole, implants lose a certain amount of stability in the first 14 days following implantation, and this is reflected by an increase in the Periotest values of one to two units. However, once the healing phase is over, the Periotest values obtained will be similar to those immediately following implantation (primary stability). Significantly greater increases in Periotest values, even a number of years after implantation, are an indication that the implant has become unstable, one of its screws has loosened, or it has excess pressure or has become infected (e.g. periimplantitis). It is therefore advisable to record all measurements to allow monitoring checks to be conducted over time.
Diagnosis and assessment of periodontopathies
While the Periotest value closely correlates with the tooth mobility,
it is not the result of a conventional measurement of the tooth. The
following correlations apply:
| Clinical degree of loosening | Periotest value |
| 0 | -08 to +09 |
| I | +10 to +19 |
| II | +20 to +29 |
| III | +30 to +50 |
There are also tables for use with natural teeth, that indicate which Periotest values can be expected for a healthy periodontium. Please see the relevant literature for further information.
Early diagnosis of diseases of the periodontium:
Incipient or existing periodontal structural changes, including occlusal
traumas, can be determined with considerable accuracy during routine
examinations - before they can be detected on a dental roentgenogram.
Monitoring of treatment by follow-up examinations:
Objective, reproducible, and simple measurement permits the regular
monitoring of the success of any periodontal, orthodontic, and functional
therapeutic steps. The effect of occlusal disorders, and also adjustment,
can be evaluated objectively. Monitoring of prophylactic measures,
e.g. following removal of dental calculus, teaching oral hygiene,
and periodontal therapy. Reduction of the radiation exposure associated
with the monitoring of treatment.
Help in decision making for further treatment
Rapid and objective determination of the suitability of a treated tooth
for use as an anchor for further therapeutic measures. Periodontal
reconstruction and orthodontic procedures can be quantified.
Detection of occlusal overloading:
From the difference in the Periotest values during occlusion and in
the absence of occlusion, occlusal overloading can be detected when
this is greater than 6 Periotest values. This makes possible the
immediate monitoring of occlusal adjustment in the case of almost
all forms of occlusal treatments.
Periotest values are independent from such clinical parameters as condition of dental fillings, overlapping of teeth, presence of crowns or enamel defects.
The Periotest measuring procedure is electromechanical. An electrically driven and electronically monitored tapping head percusses the test object (tooth or implant) 16 times. The entire measuring procedure requires approx. 4 seconds. The tapping head is pressure sensitive and records the duration of contact with the test object. Loose teeth or implants display a longer contact time and the Periotest values are correspondingly higher, while sturdy teeth or well osseointegrated implants have a short contact time and result in low Periotest values.
To ensure that the measurement is valid and meaningful, it is important to ensure that the handpiece is positioned correctly with respect to the test object (distance, angle). The device itself provides assistance by monitoring all 16 impulses. Incorrect impulses are eliminated to ensure reliable and reproducible measurements.