Leena Saxén

Autosomal recessive inheritance of juvenile periodontitis: test of a hypothesis.

The heredity of juvenile periodontitis was studied in a series of 30 families. None of the 60 parents showed any sign of this disease. Of the 52 siblings, nine in seven families were affected. The calculated genetic ratio concurred with the hypothesis of autosomal recessive inheritance based on the results of an earlier study of 31 families (Saxén 1980).

The parotid gland is the main source of human salivary epidermal growth factor

To clarify the production of human epidermal growth factor (EGF) by different salivary glands, we measured its concentration by radioimmunoassay separately in whole saliva, in parotid gland (PG) saliva and in mixed submandibular (SMG) and sublingual gland (SLG) saliva. Also, we studied the presence of EGF in PG and SMG by immunohistochemistry. The mean (geometric) concentrations of EGF in PG saliva (2704 pg/ml, +/- SEM interval 2393-3056 pg/ml, n = 20) was higher (p less than 0.001) than in whole saliva (864 pg/ml, +/- 733-1019 pg/ml, n = 29), which in turn was higher (p less than 0.001) than in mixed SMG + SLG saliva (357 pg/ml, +/- 296-430 pg/ml, n = 16). No sex difference existed in any salivary gland EGF. Immunohistochemistry revealed EGF in the acinar cells of both PG and SMG, but only in PG there were prominent EGF deposits in luminal spaces. Our data suggest that EGF is produced by both PG and SMG, but that more of it is secreted from the PG. This result is new and challenges the general view that human salivary EGF is mainly from SMG. In mouse almost all salivary EGF comes from SMG and its amount is androgen dependent. Thus there are great differences in sources and regulation of salivary EGF between man and mouse.

Increased tendency towards gingival bleeding caused by joint effect of α-tocopherol supplementation and acetylsalicylic acid

Alpha-tocopherol (vitamin E) may play a role in the treatment of arterial thromboembolic disease, possibly by inhibiting platelet aggregation. Thus far, no clinical evidence exists for this effect. The objective of this study was to assess the effect of alpha-tocopherol supplementation on gingival bleeding either in combination with acetylsalicylic acid (ASA) or without it. This study was an end-point examination of a random sample of male smokers who had participated in a controlled clinical trial, the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (ATBC Study) for 5-7 years. The study included 409 men aged 55-74 years of whom 191 received alpha-tocopherol supplementation (50 mg/day); 56 used ASA, 30 received both and 132 received neither. Gingival bleeding was examined by probing with a WHO probe and reported as a percentage of bleeding sites adjusted by the logistic regression model. Gingival bleeding was more common in those who received alpha-tocopherol compared with nonreceivers among subjects with a high prevalence of dental plaque (P < 0.05). ASA alone increased bleeding only slightly. The highest risk of gingival bleeding was among those who took both alpha-tocopherol and ASA (33.4% of probed sites bleeding vs 25.8% among subjects taking neither alpha-tocopherol nor ASA, P < 0.001). In the ATBC Study, more deaths from haemorrhagic stroke and fewer from ischaemic heart disease were observed among those participants who received alpha-tocopherol compared with those who did not. Based on the results of the present study and the ATBC Study, we conclude that alpha-tocopherol supplementation may increase the risk of clinically important bleedings, particularly when combined with ASA.

The long-term efficacy of systemic doxycycline medication in the treatment of localized juvenile periodontitis

The presence of Actinobacillus actinomycetemcomitans in the deep periodontal pockets of patients with localized juvenile periodontitis has been causally associated with active periodontal destruction. Thus, eradication of this microorganism has become the goal of treatment. It has been postulated that such eradication cannot be achieved without systemic antimicrobial treatment. The efficacy of a semisynthetic tetracycline (doxycycline) in a double-blind follow-up study of 14 patients with localized juvenile periodontitis was evaluated. For assessment of the periodontal status, probing depth and bleeding after probing at 4 sites of all teeth were recorded. The treatment consisted of instruction in oral hygiene, scaling and root planing, periodontal surgery and systemic medication for 2 weeks with either doxycycline (Doximycin) or placebo. A. actinomycetemcomitans was cultivated from subgingival samples taken from 4 sites. The periodontal condition and the prevalence of A. actinomycetemcomitans were monitored at the baseline and at 2, 8 and 20 months. The periodontal condition improved in both groups; the only significant difference was a greater reduction in the prevalence of A. actinomycetemcomitans 8 months after treatment with doxycycline as compared with the placebo.

The immediate efficacy of adjunctive doxycycline in treatment of localized juvenile periodontitis.

A randomized, double-blind, placebo-controlled study on the immediate clinical and microbiological efficacy of doxycycline (100 mg for 14 days) was carried out to determine the benefit of adjunctive medication in 16 patients with localized juvenile periodontitis. Measurements of gingival fluid flow, probing depths, bleeding on probing and suppuration were determined at 2 periodontal sites with and 2 without radiographic attachment loss, at weeks 0, 1, 3 and 8. Subgingival bacterial samples were taken with curettes from the same sites. Spirochaetes were searched for by dark-field microscopy. Actinobacillus actinomycetemcomitans, pigmented and non-pigmented Bacteroides spp., Capnocytophaga, Fusobacterium and Actinomyces spp. were cultured on various selective and non-selective media. Bacterial species found at least in 50% of the patients and comprising on average 5% or more of the cultivable flora were included in the analysis. Neither short-term clinical nor microbiological efficacy beyond that of a course of mechanical debridement alone was found by using systemic medication with doxycycline in patients with localized juvenile periodontitis.

Salivary defense mechanisms in juvenile periodontitis

The local, saliva-associated defense mechanisms of 28 juvenile periodontitis (JP) patients and their age- and sex-matched controls were studied. Lysozyme, lactoferrin, salivary peroxidase, myeloperoxidase, and thiocyanate concentrations were determined from both whole saliva and parotid saliva. The total concentrations of salivary IgA, IgG, and IgM were assayed. The periodontal condition and the salivary flow rates were registered. Among the JP patients, a significantly elevated concentration of IgG was found in parotid saliva but not in whole saliva. Salivary peroxidase activities were significantly low both in the whole and in the parotid saliva samples of the JP patients, and leukocyte-derived myeloperoxidase was present in significantly low amounts in whole saliva of these patients. Because both glandular (salivary peroxidase) and polymorphonuclear-cell-derived (myeloperoxidase) enzyme activities were low among the JP patients, suppressed peroxidase-mediated host defense mechanisms could be characteristic of JP.

Chemotaxis and surface glycoproteins of neutrophil granulocytes from patients with juvenile periodontitis.

Neutrophil granulocytes were isolated from the peripheral blood of eight patients with juvenile periodontitis and their healthy controls. The cells were radioactively surface-labelled by the periodate-sodium boro-[3H]-hydride method and their surface glycoproteins studied by polyacrylamide gel electrophoresis and isoelectric focusing. The chemotaxis and chemokinesis were studied against casein. The results indicate that the cells of the patients have normal surface glycoprotein structure and do not show defect in chemotaxis.

In vitro inhibition of mouse odontoblast differentiation by vitamin A.

Abstract An excess of vitamin A prevented tooth morphogenesis and odontoblast differentiation in cultured embryonic mouse molar tooth germs. If the vitamin A was added after the onset of odontoblast differentiation, it did not affect the secretion of predentine or the polarization of ameloblasts but it reduced the epithelial component and impaired keratinization. The effects were reversible. Autoradiographically, in control germs the highest incorporation of 35SO4 was observed at the epithelio-mesenchymal interface. Vitamin A decreased this incorporation. The ultrastructure of the epithelio-mesenchymal interface was examined in expiants in which the epithelial and mesenchymal components of the tooth germ were separated enzymically and then cultured as recombinants. The basement membrane was restored after 2 days in the control medium but not in the presence of vitamin A. The results support the hypothesis that a cell-matrix type of interaction is involved in the differentiation of odontoblasts and suggest that extracellular matrix and cell surface macromolecules, such as sulphated glycos-aminoglycans, are necessary in odontoblast differentiation.

Effect of two antimicrobial rinses and oral prophylaxis on preoperative degerming of saliva

Two degerming mouthrinses, a 1% povidone-iodine and a 0.2% aqueous solution of chlorhexidine gluconate, were tested with regard to their degerming effect on the saliva. The study comprised two parts. In the first part 19 dental students with good oral hygiene rinsed their mouths at weekly intervals with 10 ml of the povidone-iodine and 10 ml of the chlorhexidine solution. A control group of 12 students and nurses with healthy teeth and gums rinsed their mouths with 10 ml of plain water. In the second part 11 adult patients with periodontal disease used the two test rinses at weekly intervals both before and after periodontal prophylaxis including scaling of the teeth. Non-stimulated saliva was simpled immediately before and 5, 30, 60, and 120 min after each rinse. Part of the saliva was cultured on blood agar plates to show the growth of aerobic microbes. The remainder of the saliva was poured over a Dentocult dip-slide for determination of the number of acidophilic bacteria. The results showed that in the water control group the bacterial count increased in spite of the rinse. When compared with the prerinse values, both test rinses clearly reduced the amounts of bacteria. Chlorhexidine reduced the bacterial count 5 min after the rinse about one logarithm more than povidone-iodine, did, and the degerming effect of chlorhexidine was also of longer duration than that of the povidone-iodine solution. The periodontal prophylaxis in the adult group did not seem to lower the pre-rinse bacterial counts but did slightly improve the duration of the effect of both test solutions. The dip-slide tests showed that 28% of the subjects had no growth of acidophilic bacteria. This absence was not dependent on the other bacterial flora of the saliva. In the cases with a positive dip-slide test, the number of acidophilic bacteria decreased with both test solutions according to the pattern revealed by the blood agar plate cultures.