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Voorbereidingsopdracht(en)
Bestudeer:
- van der Velden, U & de Vries, J.H. (1978). Introduction of a new periodontal probe: the pressure probe. J Clin
Periodontol. 5: 188-197.
Abstract. A new periodontal probe has been developed: the pressure probe. The probe consists of a cylinder
and piston assembly connected to a variable air pressure system. The working end is a metal tube in which a
plunger can move freely. By means of air pressure the plunger is constantly fully extruded. During probing the
plunger will intrude from the position of maximum extrusion only as the probing force exceeds the
predetemined force acting on the plunger. The difference by which the plunger is intruded can be read on a
millimeter scale within the handle of the probe. The purpose of the present investigation was to determine
whether probing force is constant during probing, to study the reliability of reading pocket depth
measurements in vitro, and to investigate the relationship between pocket depth and applied force in man. In
order to evaluate whether the probing force is constant during probing, measurements were performed on a
force transducer. Results show that the device makes probing possible with a constant and adjustable
pressure. The influence of the reading of the calibration on pocket depth assessment in vitro was studied in an
in vitro model. Results show that pocket depths of 1 mm to 8 mm ± 0.25 mm were read correctly in about 90 %
of instances. Generally about 45 % of the half millimeter values were recorded as the lower whole millimeter.
To investigate the relationship between pocket depth and applied force, 173 pocket depth measurements were
performed in eight patients. Patients selected for this study had, in some part of the upper anterior segment,
loss of alveolar bone support up to two-thirds of the root length, visible on periapical radiographs. All patients
received preliminary treatment consisting of plaque control and removal of subgingival deposits. The mean
Sulcus Bleeding index score was 0.2. Pocket depth measurements were carried out with forces of 0.15, 0.25,
0.50 and 0.75 N. Both approximal and vestibular pocket depths were recorded. In this study 0.75 N was chosen
as the maximal force since in a pilot study a force of 1.0 N appeared too painful for patients. Results show an
increasing pocket depth with increasing probing force. The mean pocket depths increased from 2.08 mm at
0.15 N to 3.71 mm at 0.75 N. Testing showed it to be statistically significant. At 0.75 N, 72 out of the 173
pockets examined were equal to or deeper than 4 mm. The percentages were calculated of differences equal
to or more than 2 mm between pocket depth measurements carried out with 0.75 N and lower forces. It was
found that 63.3 % of pocket depths measured with 0.15 N were, when measured with 0.75 N, 2 mm or more
deeper. This was 43.1 % when 0.25 N and 0.75 N were compared and 9.7 % when 0.50 N and 0.75 N were
compared. The maximal differences varied from 5 mm to 7 mm.
- van der Velden, U. (1979). Probing force and the relationship of the probe tip to the periodontal tissues. J Clin
Periodontol. 6: 106-114.
Abstract. Recently an increasing pocket depth was found to be related to an increasing probing force. The
purpose of the present study was to investigate whether or not a plateau value in pocket depth measurements
exists and to study, with different probing forces, the location of the tip of the probe in relation to the
periodontal fibers and the alveolar bone. Two groups of patients were selected for this study; in one group a
number of teeth had to be extracted for periodontal reasons (the extraction group) and in the other a single
periodontal surgical procedure was required (the surgery group). All patients received preliminary treatment
consisting of plaque control and removal of subgingival deposits. At the time of the investigation the gingival
condition was assessed by means of a new index, the Periodontal Pocket Bleeding Index (P.P.B.I.) The criteria
were: 0 - no bleeding of the pocket after probing with a force of 0.75N, and 1 - bleeding of the pocket within 30
sec after probing with a force of 0.75N. After local anesthesia in the extraction group, reference marks parallel
to the long axis of the experimental teeth were cut with a cylindrical diamond burr. By means of the pressure
probe, pocket depth measurements were performed with increasing forces of 0.50, 0.75, 1.00 and 1.25N. After
extraction and staining of the remnants of the periodontal fibers, the distance from the most coronal intact
connective tissue fibers to the most apical point of the reference marks was measured. In the surgery group
using the same pressure probe, interproximal measurements with increasing forces of 0.50, 0.75, 1.00 and
Voorbereidingsopdracht(en)
Bestudeer:
- van der Velden, U & de Vries, J.H. (1978). Introduction of a new periodontal probe: the pressure probe. J Clin
Periodontol. 5: 188-197.
Abstract. A new periodontal probe has been developed: the pressure probe. The probe consists of a cylinder
and piston assembly connected to a variable air pressure system. The working end is a metal tube in which a
plunger can move freely. By means of air pressure the plunger is constantly fully extruded. During probing the
plunger will intrude from the position of maximum extrusion only as the probing force exceeds the
predetemined force acting on the plunger. The difference by which the plunger is intruded can be read on a
millimeter scale within the handle of the probe. The purpose of the present investigation was to determine
whether probing force is constant during probing, to study the reliability of reading pocket depth
measurements in vitro, and to investigate the relationship between pocket depth and applied force in man. In
order to evaluate whether the probing force is constant during probing, measurements were performed on a
force transducer. Results show that the device makes probing possible with a constant and adjustable
pressure. The influence of the reading of the calibration on pocket depth assessment in vitro was studied in an
in vitro model. Results show that pocket depths of 1 mm to 8 mm ± 0.25 mm were read correctly in about 90 %
of instances. Generally about 45 % of the half millimeter values were recorded as the lower whole millimeter.
To investigate the relationship between pocket depth and applied force, 173 pocket depth measurements were
performed in eight patients. Patients selected for this study had, in some part of the upper anterior segment,
loss of alveolar bone support up to two-thirds of the root length, visible on periapical radiographs. All patients
received preliminary treatment consisting of plaque control and removal of subgingival deposits. The mean
Sulcus Bleeding index score was 0.2. Pocket depth measurements were carried out with forces of 0.15, 0.25,
0.50 and 0.75 N. Both approximal and vestibular pocket depths were recorded. In this study 0.75 N was chosen
as the maximal force since in a pilot study a force of 1.0 N appeared too painful for patients. Results show an
increasing pocket depth with increasing probing force. The mean pocket depths increased from 2.08 mm at
0.15 N to 3.71 mm at 0.75 N. Testing showed it to be statistically significant. At 0.75 N, 72 out of the 173
pockets examined were equal to or deeper than 4 mm. The percentages were calculated of differences equal
to or more than 2 mm between pocket depth measurements carried out with 0.75 N and lower forces. It was
found that 63.3 % of pocket depths measured with 0.15 N were, when measured with 0.75 N, 2 mm or more
deeper. This was 43.1 % when 0.25 N and 0.75 N were compared and 9.7 % when 0.50 N and 0.75 N were
compared. The maximal differences varied from 5 mm to 7 mm.
- van der Velden, U. (1979). Probing force and the relationship of the probe tip to the periodontal tissues. J Clin
Periodontol. 6: 106-114.
Abstract. Recently an increasing pocket depth was found to be related to an increasing probing force. The
purpose of the present study was to investigate whether or not a plateau value in pocket depth measurements
exists and to study, with different probing forces, the location of the tip of the probe in relation to the
periodontal fibers and the alveolar bone. Two groups of patients were selected for this study; in one group a
number of teeth had to be extracted for periodontal reasons (the extraction group) and in the other a single
periodontal surgical procedure was required (the surgery group). All patients received preliminary treatment
consisting of plaque control and removal of subgingival deposits. At the time of the investigation the gingival
condition was assessed by means of a new index, the Periodontal Pocket Bleeding Index (P.P.B.I.) The criteria
were: 0 - no bleeding of the pocket after probing with a force of 0.75N, and 1 - bleeding of the pocket within 30
sec after probing with a force of 0.75N. After local anesthesia in the extraction group, reference marks parallel
to the long axis of the experimental teeth were cut with a cylindrical diamond burr. By means of the pressure
probe, pocket depth measurements were performed with increasing forces of 0.50, 0.75, 1.00 and 1.25N. After
extraction and staining of the remnants of the periodontal fibers, the distance from the most coronal intact
connective tissue fibers to the most apical point of the reference marks was measured. In the surgery group
using the same pressure probe, interproximal measurements with increasing forces of 0.50, 0.75, 1.00 and
