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Notes: Abstract The present study investigated the location of the gingival margin, following denudation of the interdental alveolar bone. In seven patients apically positioned flap procedures were performed in such a way that complete interdental denudation was achieved. Teeth showing interdental osseous craters were excluded from the study. Three years post-treatment a mean pocket depth of 2.17 mm was found. No differences in attachment level prior to and 3 years after treatment could be assessed.Results showed a mean distance of 4.33 mm between the location of the gingival margin 3 years post-treatment and the bone level during surgery. This finding is discussed in relation to the question of how much alveolar bone should be removed if, in case of extensive carious lesion or crown fracture, the cervical outline of the restoration is located near the bone level.

Notes: Abstract. This study investigates the relationship between probing force and probe penetration into the periodontal tissues in pockets with overt gingivitis and in pockets with minimal gingival inflammation. In eight dogs experimental periodontal tissue breakdown was induced during a period of 14 weeks. The dogs were then distributed over two groups of four dogs each. In one group the dogs were subjected to meticulous tooth cleaning once every day for a period of 3 weeks. The dogs in the second group did not receive any oral hygiene measures. Next, wooden probes were inserted, mesial and distal to each premolar. In each dog six different probing forces were used. Microscopic examination showed that, in the brushed group, epithelium was always present between the probe tips and the connective tissue. In the nonabused group presence of epithelium was found in 21 of 23 specimens. In both groups of dogs it was found that, with increasing probing forces, the location of the tips of the probes changed from a position occlusal to the most coronal connective tissue fibers to a position apical to the most coronal connective tissue fibers. With light probing forces it appeared that in the nonbrushed group the tips of the probes were located more apically. When greater probing forces were used, no differences between the brushed and the nonbrushed group were found. It is suggested that, using a probe of 0.63 mm in diameter, the optimal force level for clinical pocket measurements is about 0.75 N, or in other words, the optimal probing pressure is about 240 N/cm2.〈section xml:id="abs1-1"〉〈title type="main"〉ZusammenfassungMikroskopische Wertung von Messungen der Taschentiefe am Hunde bei Anwendung sechs verschiedener Sondierungsdruckstärken In dieser Studie wird das Verhältnis zwischen der Sondierungskraft und der Penetration der Sondern in das Parodontalgewebe bei Zahnfleischtaschen mit seitlicher und mit minimally Gingivitis untersucht. Bei 8 Beagle Hunden wurde während einer Zeitspanne von 14 Woched experimcntelle Parodontolyse induziert. Die Hunde wurden in zwei Gruppen zu je 4 Hunden aufgeteilt. Bei der einen Gruppe wurden die Zähne während einer Periode von 3 Wochen cinmal täglich Gorgfältig gereinigt. Bei den Hunden der zweiten Gruppe wurden keine mundhygienischen Massnahmen durchgefürt. Dann wurden mesial und distal eines jeden Prämolaren Holzsonden mit 6 verschiedenen Druckstärken in die Taschen inseriert, Untersuchungen mit dem Mikroskop zeigten, dass bei der “gereinigten” Gruppe stets Epithel zwischen der Sondenspitzen und dem Bindegewebe vorhanden war. In der Gruppe ohne Mundhygiene wurde in 21 von 23 Fällen Epithel angetroffen. In beiden Gruppen wurde gefunden, dass die Sondenspitzen bei zuneh mendem Sondierdruck ihre Lage veränderten und zwar von okklusal der am weitesten koronal gelegenen Bindegewebsfasern bis zu ihrer apikalen Seite, Bei Anwendung von geringem Sondierungsdruck zeigte es sich, dass die Sondenspitzen bei der Gruppe ohne Mundhygiene tiefer zu liegen kamen. Bei stärkerem Sondierungsdruck wurden keine Unterschiede zwischen den Versuchsgruppen gefunden. Es wird vermutet, dass bei klinischen Messungen von Zahnfleischtaschen die optimale Sondierungskraft einer Sonde von 0,63 mm bei ungefähr 0,75 N Hegt, oder anders ausgedrückt beträgt der optimale Sondierungsdruck ungefähr 240 N/cm2〈section xml:id="abs1-2"〉〈title type="main"〉RésuméEvaluation microscopique des mensurations de la profondeiir des culs-de-sac pratiquées chez le chien en employant six forces de sondage différentesCette étude examine le relation existant entre la force de sondage et la pénétration de la sonde dans les tissus parodontaux an niveau de culs-de-sac avec gingivile manifeste et de culs-de-sac avec inflammation gingivale minime. Chez huit chiens briquets, une destruction expérimentale du parodonte a été provoquée pendant une période de 14 semaines. Les chiens ont alors été répartis en deux groupes de quatre chiens. Dans Tun des groupes, les chiens ont été soumis á un nettoyage minutieux des dents une fois par jour pendant une période de trois semaines. Les chiens de l'autre groupe n'ont reçu aucun soin d'hygiène buccale. Des sondes de bois ont ensuite été introduites du côté mesial et du côté distal de chaque prémolaire. Chez chacim des chiens, six forces de sondage différentes ont été employées. Un examen microscopique a montré que, dans le groupe dont les dents avaient été brossées, l'épithélium était toujours présent entre l'extrémité de la sonde et le tissue conjonctif. Dans le groupe dont les dents n'avaient pas été brossées, la présence d'épithélium a été trouvée dans 21 des 23 specimens. Dans les deux groupes, on a trouvé que, lorsque la force de sondage augmente, il se produit un changement dans la position de I'extrémité de la sonde: elle passe d'un niveau situé du côté occlusal des fibres de tissu conjonctif les plus coronaires, a un niveau situé du côté apical de ces fibres. Lorsqu'on utilisait de légères forces de sondage, on constatait que l'éxtrcmite de la sonde dans le groupe sans brossage des dents était située à un niveau plus apical. Lorsqu'on utilisait des forces de sondage plus élevées, on ne constatait pas de différence entre le groupe avec et le groupe sans brossages des dents. II semblerait que, lorsqu'on utilise une sonde de 0,63 mm de diamètre, le niveau optimum de force à utiliser pour les mensurations cliniques des culs-de-sac scrait d'environ 0,75 N, ou, en d'autres termes, la presslon de sondage optimum serait d'environ 240 N/cm2.

Notes: Abstract In four beagle dogs, periodontal tissue breakdown was experimentally induced around the upper left premolars (P1, P2 and P3). Wooden probes were inserted mesially and distally to each premolar. Six different probing forces were used in each dog. Microscopic examination showed:〈list style="custom"〉1) the presence of an intact layer of epithelium between the probe tip and the connective tissue in 21 of 23 specimens.2) an increasing compression of the connective tissue with increasing probing force, without penetration of the probe tip into the connective tissue.

Notes: Abstract This study investigates the effect of initial treatment on 1) probing force related to probing depth, 2) the attachment level, 3) the position of the gingival margin and 4) the clinical signs of color and change of contour of the gingiva in relation to the bleeding tendency of a pocket. It also addresses the question of whether, in deep inflamed periodontal pockets, the tip of the probe is located at the attachment level when a probing force of 0.75N is used, as has already been shown in pockets related to noninflamed gingival margins. Four different probing forces are used: 0.15N, 0.25N, 0.50N and 0.75N and results show an increasing probing depth with an increasing probing force, both before and after treatment. Initial treatment results in a decrease of mean probing depth but the change is dependent on the applied probing force. The mean probing depth reduction decreased from 1.71 mm (assessed with 0.15N) to 1.24 mm (assessed with 0.75N). Since results from this and a previous study indicate that both before and after treatment the tip of the probe is located at the attachment level when a probing force of 0.75N is used, it may be postulated that the reduction of mean probe-tip level measurements (= probing depth measurement from a fixed point) reflects a degree of connective tissue reattachment. Patients in the initial treatment study were selected on the basis of obvious redness and swelling of the gingiva. After treatment, both of these symptoms almost disappear, whereas the Periodontal Pocket Bleeding Index (P. P. B. I.) decreases only from 0.87 before treatment, to 0.45 after treatment.

Notes: 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.

Notes: Abstract This was a 2-part study. The purpose of the 1st part was to examine the relationship between brushing force and plaque removal efficacy comparing a regular manual toothbrush (M) with an electric toothbrush the Braun Oral-B Plak Control* (B). The study consisted of a single oral prophylaxis followed by 5 experiments which differed solely in respect to toothbrushing force. At baseline (after 24-h plaque accumulation), the amount of dental plaque was evaluated and subsequently, the subject's mouth was brushed by a dental hygienist. Brushing was carried out in a random split-mouth order. Either the 1st and 3rd quadrants or the 2nd and 4th quadrants were brushed with 1 toothbrush and the 2 remaining quadrants with the other. The available time for the brushing procedure was 2 min. After brushing, the amount of remaining dental plaque was assessed. The force used in experiment 1 through 5 was 100, 150, 200, 250, 300 g, respectively. The results show that when brushing force is increased, more plaque is removed with either of the two brushes. Except for the high brushing force (300 g), the electric toothbrush removed more plaque than the manual brush. The purpose of the 2nd part was to evaluate the habitual brushing force which individuals use with various toothbrushes. Besides a manual toothbrush (M), 3 electric toothbrushes were examined, the Rotadent® (R). Interplak® (I) and Braun® (B). 20 subjects were selected on the basis of being ‘good brushers” (plaque score at screening 〈25%). At baseline, each subject randomly received 1 of the 4 brushes. They were allowed a training period of 3 weeks at the end of which they were asked to abstain from brushing for at least 24 h. The plaque (Turesky modification of the Quigley & Hein) was scored, after which the subjects brushed their teeth (2 min) with the assigned toothbrush equipped with a strain gauge. A computer set–up measured (100 Hz) and calculated the mean brushing force. After brushing, the amount of remaining plaque was assessed. The design of the study was a 4-way cross-over. The results show that with a manual brush, considerably more force is used than with the electric brushes (R=96. 1 = 119. B= 146, M=273). No significant relation between brushing force and plaque removal was demonstrated for any of the brushes.

Notes: Abstract The purpose of the present study was to compare the Braun/Oral-B Plak Control® (D7) and Sonicare® (S) in their plaque-removing efficacy. For this study. 35 university students (non-dental) were selected. This was a 2-part study. Prior to each appointment, all subjects were asked to abstain from all oral hygiene procedures for at least 24 h. In Part 1. the efficacy of the toothbrush was studied when one of the investigators brushed the teeth of the panellists. In Part 2. the efficacy of toothbrushing was studied after the students had received professional instruction. The available time for the brushing amounted to a total of 2 min per mouth. Dental plaque was evaluated by means of the Silness and Löe plaque index assessed at 6 sites per tooth. Results showed that both in Parr 2 and Pan I the D7 removed significantly more plaque than the S-electric toothbrush. The plaque reduction assessed according to Silness and Löe in Part 1 was for the D7. 1.28 and for the S, 1.12. In Pan 2. the reductions were 0.90 and 0.80. respectively. The majority (n=34) of subjects preferred the D7 over the S. In conclusion, the results of the present study show that the oscillating/rotating toothbrush (Braun/ Oral-B Plak Control®) is more effective in plaque removal than the sonic electric toothbrush (Sonicare®). In addition, given a choice, the panellists preferred the oscillating/rotating electric toothbrush.

Notes: Abstract The aim of the present investigation was to study longitudinally the periodontal condition of married couples. The data are derived from a longitudinal study in a young population living in a remote village in Indonesia and showing a relatively high prevalence of periodontal destruction. In 23 married couples, clinical measurements were carried out in 1987 and 1994. During the latter examination, a pooled gingival sample was obtained for microbiological evaluation. In 1994. the mean age of the group was 29.1 years and the couples were married for on the average 10 years. In each couple, the partner showing in 1994 the highest score for mean loss of attachment (LA) was classified as the diseased proband and the other partner as the spouse. Evaluation of the clinical data showed that: (11 the diseased probands already had in 1987 a worse periodontal condition compared to that of the spouses; (2) in both groups the mean LA increased during the 7-year period;13) the difference in mean LA between diseased probands and spouses increased between 1987 and 1994. The microbiological evaluation revealed a relatively high prevalence of Actinobadllus actinomycetemcomitans (50%). Porphyromonas gingivalis (67%) and Prevotella intermedia 61%. Analysis showed no differences in microbiota between diseased probands and spouses. The 23 Actinobadllus actinomycetemcomitans positive subjects included 2 positive couples. Furthermore, the 31 Porphyrormmas gingivalis and 28 Prevotella intermedia positive subjects included 9 and 7 positive couples respectively. In conclusion, 10 years of cohabitation showed no influence on the periodontal condition of the spouses.

Notes: Abstract The purpose of this study was to compare a commercially available DNA probe technique with conventional cultural techniques for the detection of Actinobacillus actinomvcelemconntans. Porplivrotnonas gingivalis and Prevotella intermedia in subgingival plaque samples. Samples from 20 patients with moderate to severe periodontitis were evaluated at baseline and during a 15 months period of periodonlal treatment. Paperpoints from 4 periodontal pockets per patient were forwarded to Omnigene for DNA probe analysis, and simultaneously inserted paperpoints from the same pockets were analyzed by standard culture techniques. In addition, mixed bacterial samples were constructed harbouring known proportions of 25 strains of A. actinomycetemcomitans, P. gingivalis and P. intermedia each. A relatively low concordance was found between both methods. At baseline a higher detection frequency was found for A. actinomycetemcomitans and P. gingivalis for the DNA probe technique; for P. intermedia the detection frequency by culture was higher. For A. actinomycetemcomitans, 21% of the culture positive samples was positive with the DNA probe. Testing the constructed bacterial samples with the DNA probe method resulted in about 16% false positive results for the 3 species tested. Furthermore. 40% of P. gingi-valis strains were not detected by the DNA probe. The present data suggest that at least part of the discrepancies found between the DNA probe technique used and cultural methods are caused by false positive and false negative DNA probe results. Therefore, the value of this DNA probe method for the detection of periodontal pathogens is questionable.

Notes: Abstract. The purpose of the present study was to compare the Braun Plak Control® (D7) and Philips HP 500® (MM) in their plaque removing efficacy. Furthermore the brushing force applied by the panellist on the brush-head with both these brushes was evaluated. For this study, 35 university students (non-dental) were selected. The study consisted of 3 experiments. Prior to each experiment, all subjects were asked to abstain from all oral hygiene procedures for at least 48 h. In Exp. I, the efficacy of toothbrushing was studied when one of the investigators brushed the teeth of the panellists. In Exp. II, the efficacy of the brushing was studied after the students had received a professional instruction. In Exp. III, the brushing force used during a single brushing exercise was evaluated. The available time for the brushing amounted to a total of 2 min per mouth. Dental plaque was evaluated by means of the Silness and Löe and Quigley and Hein plaque indices assessed at 6 sites per tooth. Results showed that both in Exp. I and Exp. II, the D7 removed significantly more plaque than the MM electric toothbrush. The plaque reduction assessed according to Silness and Löe in Exp. I was for the D7, 1.07 and for the MM, 0.78. In Exp. II, the reduction was 1.08 and 0.88, respectively. The results of Exp. III show that the mean brushing force was comparable for both brushes (D7=I73 g, MM=I75 g). All 35 subjects were allowed to choose one electric toothbrush as compensation for their participation. The majority (n=26) of subjects preferred the D7 to the MM. In conclusion, the results of the present study show that given a choice, there was a preference of the panellists for the D7. No difference in brushing force was observed between the 2 brushes. Evaluation of plaque removing efficacy showed that the Braun Plak Control® is more effective than the Philips HP 500®.