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Notes: Background, aims: In order to investigate the rôle of various putative clinical and microbiological risk markers, a longitudinal study was initiated in a young population deprived of regular dental care. In 1987 all inhabitants in the age range 15–25 years living in a village with approximately 2000 inhabitants at a tea estate on Western Java, Indonesia, were examined clinically and microbiologically. In total, 167 subjects of the original group of 255 adolescents were re-examined in 1994. The material presented in this paper describes the clinical periodontal condition at baseline (1987) and at follow-up (1994), 7 years later. Furthermore, the relationship between progression of the disease and baseline clinical and microbiological data was assessed.Methods: Plaque index (PI), bleeding on probing (BOP), pocket depth (PD), and attachment loss (AL) were scored at the approximal surfaces of the vestibular aspects of all teeth. The number of approximal surfaces of the Ramfjord teeth showing subgingival calculus was recorded. At baseline, the dorsum of the tongue, the buccal gingiva in the upper jaw, the saliva and the deepest bleeding pocket without clinical loss of attachment were sampled for microbiological examination with phase contrast microscopy and indirect immunofluorescence.Results: Mean values at baseline and at follow-up were PI: 1.01 and 1.15, BOP: 0.80 and 1.16, PD 3.26 mm and 3.32 mm, AL: 0.33 mm and 0.73 mm, respectively. All parameters except PD showed a statistically significant increase over the 7-year period. The prevalence of the studied bacteria irrespective of the sample site was: A. actinomycetemcomitans 53%, P. gingivalis 88%, P. intermedia 100%, spirochetes 89% and motile micro-organisms 100%. At the full mouth level, logistic regression showed significant odds ratios for progressive disease with age (1.15), subgingival calculus (1.20) and subgingival presence of A. actinomycetemcomitans (4.61). Presence of any of the selected micro-organisms on the mucous membranes was not related with progressive disease. In order to study local factors to explain local disease activity, each subject was characterized using the sampled pocket, which was the deepest bleeding pocket without LA at baseline, as a single response site per patient. In this constrained design, the main statistical factors associated with progressive disease were presence of motile micro-organisms and the plaque score.Conclusions: This study identified 3 main risk markers for disease progression at the full mouth level: age, amount of subgingival calculus and subgingival presence of A. actinomycetemcomitans.

Notes: Background/aims: In an Indonesian population deprived of regular dental care, the experienced progression of disease between baseline (1987) and follow-up (1994) was investigated in relation to the composition of the subgingival microbiota at follow-up. At baseline the age ranged from 15 to 25 years. Clinical and microbiological evaluation was completed in 158 of the 167 subjects available at follow-up.Methods: Plaque index (PI), pocket depth (PD), bleeding on probing (BOP), and attachment loss (AL) were scored at the approximal surfaces of all teeth and subgingival calculus on the approximal surfaces of the Ramfjord teeth only (number of sites with subgingival calculus: NSC). A pooled sample of the deepest pocket in each quadrant was evaluated using microbiological culture techniques.Results: At baseline the mean values of the clinical parameters were AL=0.35 mm, PI=1.01, BOP=0.80 PD=3.25 mm and NSC=6.04 and at follow-up AL=0.75 mm, PI=1.16, BOP=1.19, PD=3.34 mm and NSC=5.85. All parameters except PD and NSC showed a statistically significant increase. At follow-up the prevalence of Actinobacillus actinomycetemcomitans was 40%, of Porphyromonas gingivalis 67%, of Prevotella intermedia 66%, of Fusobacterium nucleatum 79%, of Bacteroides forsythus 16%, of Campylobacter rectus 4%, and of P. micros 6%. No differences in clinical parameters were found between groups with or without these micro-organisms. In 129 subjects AL of 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE280703:ges" location="ges.gif"/〉2 mm at 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE280703:ges" location="ges.gif"/〉1 site was found. Logistic regression showed three significant odds-ratio’s for experienced progressive periodontitis: Plaque index (12.2), gender (3.4) and Actinobacillus actinomycetemcomitans (2.9).Conclusions: The results of this retrospective study suggest that plaque is the most important parameter related to experienced disease progression, and that the presence of A. actinomycetemcomitans may be associated with increased chance of disease progression.

Notes: Abstract. At present, several risk factors for the initiation and progression of periodontitis have been identified. In order to investigate the role of various potential clinical and microbiological risk factors and indicators, a longitudinal study was initiated in a young population deprived from regular dental care. The present communication describes the baseline cross-sectional data obtained in 1987 in terms of the clinical periodontal condition and prevalence of periodontal bacteria in the oral cavity. All inhabitants in the age range 15 25 years of a village with approximately 2000 inhabitants at a tea estate on Western Java, Indonesia, were examined clinically and microbiologically. In total, 255 adolescents, comprising 130 males and 125 females participated in the study. Samples for bacteriological examination were taken from the gingiva, the dorsum of the tongue, and the saliva. Plaque index, bleeding upon probing, pocket depth, and attachment loss (AL) were scored on the approximal surfaces from the vestibular aspect of all teeth as well as the mid-vestibular and mid-lingual aspects of the Ramfjord teeth. Calculus was scored only on the 4 surfaces of the Ramtjord teeth. Following the clinical measurements, the deepest bleeding pocket with no clinical loss of attachment was sampled for microbiological examination. In addition, in 37 subjects a deep bleeding (≥4 mm) with at least 4 mm of attachment loss was sampled. Moderate periodontitis (max. AL 3–4 mm) was found in 26% of the population, advanced periodontitis (max. AL ≥ 5 mm) in 8%, whereas 66% of the population showed no or minor periodontitis (max. AL 0–2 mm), Actinobacillus actinomycetetmcomitans was found in 57% of the population. Porphyromonas gingivalis in 87%. Prevotella intermedia and motile rods in all cases and spirochetes in 89%. P. gingivalis (66%), A. actinomycetemcomitans (37%) and spirochetes (63%) were, of all the sampled sites of the oral cavity, most frequently detected in pockets without attachment loss. Motile rods were most prevalent on the tongue and in the saliva (92% and 89%. respectively). A high prevalence of the investigated periodontal bacteria was detected both in the pockets without and with attachment loss. No significant association between the clinical periodontal parameters and the prevalence of the microorganisms was observed at a patient level. At a site level, both P. gingivalis and spirochetes were more prevalent in sites with attachment loss. The actual role of these putative periodontal pathogens may be elucidated more extensively, when longitudinal data on the present population become available.

Notes: The distribution of cell bodies expressing either calbindin D-28k or parvalbumin immunoreactivity in the basal forebrain and midbrain of squirrel monkeys (Saimiri sciureus) was studied on contiguous sections incubated with monoclonal antibodies raised against calbindin or parvalbumin. In the nucleus accumbens, medium-sized calbindin-positive neurons formed two cell bridges joining the ventral part of the striatum to the olfactory tubercle, whereas medium-sized parvalbumin-positive cells in the same area were much less numerous and more uniformly distributed. The medial and dorsal septal nuclei contained a small number of elongated calbindin-positive neurons and only a few parvalbumin-immunoreactive cells. In the nucleus of the diagonal band of Broca, calbindin and parvalbumin were found to label two distinct but closely intermingled neuronal populations. In the striatum, medium-sized calbindin-immunoreactive cells occurred in very large numbers and appeared to be confined to the extrastriosomal matrix. Medium-sized, parvalbumin-immunoreactive neurons were also present in the striatum but they were less numerous than the calbindin-positive cells. The calbindin-positive neurons in the dorsal portion of the striatum were less intensely stained than those in the ventral portion, whereas this pattern did not occur for neurons expressing parvalbumin immunoreactivity. At the pallidal level, neurons in both segments were devoid of calbindin but displayed a very strong parvalbumin immunoreactivity. Most of the large neurons of the nucleus basalis of Meynert were strongly calbindin-immunoreactive and many of them invaded dorsally the medullary laminae of the pallidal complex. The neurons of the subthalamic nucleus were markedly enriched with parvalbumin but displayed only light calbindin staining. In the substantia nigra/ventral tegmental area complex, calbindin-immunoreactive cells abounded in the ventral tegmental area and in the dorsal tier of the pars compacta of the substantia nigra, but were absent in the ventral tier of the pars compacta and in the entire pars reticulata of the substantia nigra. In contrast, numerous parvalbumin-immunoreactive neurons occurred in the pars reticulata and pars lateralis, but none were found in the pars compacta and ventral tegmental area. These findings reveal that the patterns of calbindin and parvalbumin distribution in primate basal forebrain and midbrain are strikingly complementary, suggesting a synergistic role for these calcium-binding proteins in basal forebrain and midbrain function.

Notes: The critical role of the subthalamic nucleus (STN) in the control of movement and parkinsonian symptoms is well established. Research in animals suggests that the cerebral cortex plays an important role in regulating the activity of the STN but this control is not known in humans. The most extensive cortical innervation of the STN originates from motor areas. Here, we used transcranial magnetic stimulation (TMS) during intraoperative single-unit recordings from STN, in six patients with Parkinson's disease (PD) undergoing implantation of deep brain stimulators, to determine whether TMS of the motor cortex (MC) modulates the activity of STN and to investigate in vivo the functional organization of the corticosubthalamic circuit in the human brain. Single-pulse TMS of the MC induced an excitation in 74.9% of neurons investigated. This activation was followed by a long-lasting inhibition of the STN neuronal activity that did not correlate with PD severity. Responsive neurons to TMS of the hand area of motor cortex were located mainly in the lateral and dorsal region of the subthalamus while unresponsive cells had a prevalently medial distribution. This is the first report of TMS-induced modulation of STN neuronal activity in humans. These findings open up new avenues for in vivo studies of corticosubthalamic interactions in human brain and PD.

Notes: The purpose of the present investigation was to study the effect of standardization of probing spot and direction of probe insertion into the pocket in conjunction with a probing force of 0.75 N on the reproducibility of pocket depth measurements. Nine patients were selected on the basis of about 50 % loss of alveolar bone support. After initial treatment 137 interproximal pockets were measured twice by three different examiners, successively by means of a pressure probe with a constant probing force of 0.75 N and a Merritt-B probe. During the next two weeks the examiners were trained by means of a video program to use the probe on a standardized spot and in a standardized direction of insertion into the pocket. After this training, all measurements were repeated in the same order of investigation. During the first as well as the second examination, the first examiner also scored bleeding on probing using the pressure probe. Analyses of variance were carried out in order to test the reproducibility of pocket depth measurements both before and after training. Possible influences of the depth of the pocket and the bleeding tendency of a pocket were included in the analyses. The results indicated that only a training program together with a standardized probing force leads to reproducible interproxima! pocket depth measurements. However, further analyses revealed that only non-bleeding pockets gave reproducible measurements whereas bleeding pockets did not. If, in addition, pocket depth was included in the analyses, it was found that this factor has no influence on the reproducibility. It was concluded that bleeding of a pocket seems to be more important for the reproducibility of pocket depth measurements than the factor pocket depth.

Notes: Background: When the subgingival presence of periodontal pathogens is studied in groups of patients or populations, mostly a number of the deepest sites is sampled. The mean clinical parameters of these deep sites are also frequently used as a the descriptor of the clinical situation of these subjects. It can be questioned, whether these 4 deep sites are capable of predicting a full-mouth situation.Aim: The purpose of the present retrospective study was to investigate to what extent the experienced progression of periodontitis as measured in the deepest approximal pocket in each quadrant reflects the disease progression at the approximal sites on a full-mouth level.Methods: A data set of a 7-year longitudinal study of 158 young subjects (69 male, 89 female, 15–25 years of age at baseline) was used. Clinical assessments included plaque index (PI), pocket depth (PD) and attachment loss (AL) at baseline (1987) and follow-up (1994). Measurements were made at the approximal surfaces of all teeth. The deepest pocket in each quadrant was determined at follow-up. Changes of the clinical parameters between baseline and follow-up were calculated both as full-mouth mean scores as well as for these 4 deepest sites. A regression analysis was used to evaluate the relationship between full-mouth score and the 4 test sites.Results: For disease progression between baseline and follow-up, significant correlation coefficients were observed between the 4-site and full-mouth mean changes (PD: 0.80, AL: 0.70, PI: 0.77). Regression coefficients were 0.51 for PD, 0.35 for AL and 0.55 for PI. The precision of the estimate for the full-mouth mean, as predicted by the 4-site mean, is determined by the residual standard deviation. This was for PD 0.31 mm, for AL 0.31 mm and for PI 0.29. Compared to the between-patient standard deviation of the full-mouth means, the residual standard deviations were high.Conclusion: In the present population, a reasonable to good correlation between full-mouth and 4-sites data was observed. However, the high residual standard deviation in the regression analysis illustrates the inaccuracy for the 4-sites data when used as a descriptive for changes in the periodontal condition on a full-mouth level. Data evaluating progression of periodontitis based on a limited number of diseased sites should be interpreted cautiously.

Notes: Abstract. In this study, the prevalence and serotype distribution of Porphyromonas gingivalis in an Indonesian population (n=158) is described. The relationship between subgingival P. gingivalis and periodontal attachment loss was investigated. The serotype distribution and periodontal parameters were studied. Serotyping was also used to study person-to-person transmission between siblings and between spouses. Approximately 50% of the subjects had periodontal attachment loss ≥3 mm at 1 or more recorded sites. The population was divided into 2 subgroups based on the presence or absence of P. gingivalis. No differences in plaque index, pocket depth, clinical attachment loss, bleeding upon probing, % of sites with ≥3 mm clinical attachment loss and % of sites with probing pocket depth 〉5 mm, were observed between both sub-populations. All known 6 capsular serotypes were found in the study population, with the exception of the K1 type. Detection of 1 of the known P. gingivalis serotypes was not related with the amount of clinical attachment loss. In 3 out of 29 sibships with more than one member positive for P. gingivalis, an identical P. gingivalis serotype was found. None of the 15 couples in the study shared an identical P. gingivalis serotype, indicating that transmission is probably not a common phenomenon in this population.