Role of brushing technique and toothbrush design in plaque removal

Twenty-four adults participated in an intraindividual crossover experimental study to compare the plaque removing ability of straight multitufted and V-shaped brushes. Twelve of the participants had loss of periodontal tissue resulting in open but healthy interdental areas while the other 12 displayed no periodontal breakdown. In part 1 the participants were asked to brush their teeth using their own brushing technique and length over two 12-day periods during which time they, at random, used one brush for the first and the other brush for the second period. In part 2 the participants were professionally brushed by two dental assistants using four brushing techniques (The Bass, The Roll, The Circular Scrub and The Horizontal Scrub) randomly assigned to the four quadrants of the mouth. Cleaning was performed once a day for two 5-day periods, during which time the participants refrained from brushing and interdental cleaning. Initial toothbrush assignment was randomized. At the beginning of the study and each test period no plaque or gingival inflammation was visible. At the end of each period the accumulated plaque was registered. The results showed that there was no difference between the two brushes tested in the unsupervised part. The plaque removing ability when using either of the brushes varied between participants. When professionally used the straight multitufted and V-shaped toothbrushes did not show any difference in plaque removal on buccal and lingual surfaces. Interproximally the V-shaped toothbrush was better at plaque removal than the straight one.(ABSTRACT TRUNCATED AT 250 WORDS)     

Bone regeneration in alveolar bone dehiscences produced by jiggling forces

The aim of this experiment was to achieve support for the hypothesis that bone resorption, induced by jiggling forces, leaves a component within the supracrestal soft tissue with a capacity of reforming bone. The maxillary lateral incisors and first premolars and the mandibular second premolars in two monkeys were used in the study. Using metal pins inserted into the neighboring teeth as retainers, orthodontic elastics were stretched and placed alternately around the buccal and lingual surfaces of each experimental tooth in order to produce jiggling forces. After 5 months of continuous jiggling, when bone dehiscences were produced on the buccal aspect of the teeth, the elastics were removed. After repositioning of the teeth a split thickness flap was raised. On one side of the jaw the soft tissue within the bone dehiscences was removed. At the contralateral teeth a sham operation was performed maintaining the soft tissue within the bone dehiscences. The monkeys were sacrificed 6 months after surgery. Tissue blocks containing test and control specimens were dissected free and prepared for microscopic analysis. The length of the supracrestal connective tissue attachment and the amount of coronal bone regeneration were assessed in the histological sections. It was found that buccal alveolar bone, reduced in height by jiggling forces, regenerated after discontinuation of the forces. When the soft tissue within the buccal bone dehiscences produced by the jiggling forces was surgically removed, the coronal regeneration of the alveolar bone was markedly reduced. These observations suggest that bone resorption, induced by jiggling forces, leaves a soft tissue component with a capacity of forming bone.     

Intracoronal radiolucencies within unerupted teeth. Case report and review of literature

A panoramic radiograph obtained during orthodontic treatment revealed an intracoronal radiolucency within an unerupted permanent second molar. This unusual entity was successfully treated by surgical and endodontic intervention, followed by restorative and orthodontic treatment. These treatments enabled the tooth to maintain pulpal vitality, erupt, complete root formation, and function. This report will review the proposed etiologies for this condition, discuss the need for surgical intervention, and present the details of the case.     

Dental pulp response to bacterial cell wall material

Lipopolysaccharides (LPS) from Bacteroides oralis and Veillonella parvula and cell wall material from Lactobacillus casei were studied for their capacity to induce leukocyte migration in the dental pulp and in an implanted wound chamber. Three adult monkeys were challenged using lyophilized material sealed into buccal Class V cavities prepared in dentin. Pulp tissue responses were observed histologically eight and 72 hours after initiation of the experiment. Subjacent to cut dentinal tubules, bacterial materials induced polymorphonuclear leukocyte (PMN's) infiltration in the pulp tissue of the majority of test teeth examined. Responses were similar for the three bacterial test materials at both time periods. Topical applications of bovine serum albumin (BSA), used as a control, induced significantly less accumulation of PMN's. Assessments of induced exudate volumes and leukocyte densities in chambers implanted in rats showed comparable rankings with pulpal experiment between test (i.e., bacterial) and control (BSA) materials. Analysis of the data indicates that high-molecular-weight complexes of bacterial cell walls may adversely affect pulpal tissue across freshly exposed dentin.     

Bacterial status in root-filled teeth exposed to the oral environment by loss of restoration and fracture or caries--a histobacteriological study of treated cases

AIM: To describe histological and microbiological findings in teeth where root fillings had been exposed to caries and the oral environment for a prolonged period. METHODOLOGY: For inclusion in the study, only teeth with a follow-up period of 3 years or more and those that had been without proper restoration for at least a period of 3 months were considered. Some root fillings had been without restoration for several years. In all, 39 roots representing 32 teeth were examined by histology. RESULTS: The majority of the specimens were without a discernible periapical bone lesion as assessed by radiography. Osteolytic lesions were seen with five roots. Longitudinal tissue sections stained with a modified Brown/Brenn staining technique revealed presence of stainable bacteria in abundance at the canal entrance and in dentinal tubules but were absent mid-root and apically in all but two specimens. Soft tissue attached to the root tip and in apical ramifications displayed distinct inflammatory cell infiltrates, suggesting microbial exposure in 7 of the 39 roots examined. In all other specimens, inflammatory cell infiltrates were either nonexistent or sparse and then associated with extruded sealer material. CONCLUSIONS: Well-prepared and filled root canals resist bacterial penetration even upon frank and long-standing oral exposure by caries, fracture or loss of restoration.     

Resting and stimulated whole salivary flow rates in Sjögren's syndrome patients over time: a diagnostic aid for subsidized dental care?

The aim of the present study was to evaluate Swedish and Norwegian criteria currently applied in the assessment of eligibility for subsidized dental care of Sjögren's syndrome (SS) patients. These criteria are partly based on a single salivary test showing a resting whole salivary secretion rate of ≤0.1 mL/min. Thirty secondary Sjögren (SSS) patients (29 F and 1 M) participated for the duration of the study, in which resting (RWS) and stimulated (SWS) whole salivary flow rates were collected in the morning and afternoon, over 3 consecutive weeks, once per week, as well as at different times over a 5-year period. Twenty patients presented levels of RWS flow rates of ≤0.1 mL/min on one or more occasions over a 3-week period, while 8 of these also exceeded, on one or more occasions, the cut-off level of 0.1 mL/min, indicating that salivary flow rates varied over time. Six patients showed consistently low secretion rates of RWS as well as of SWS, estimated as ≤0.1 mL/min and ≤0.7 mL/min, respectively. Based on the results, salivary tests that are to be used as a diagnostic aid for SS diagnosis, and thus as a basis for inclusion within the subsidy net for dental care, must be taken on several occasions in order to more accurately give information about salivary gland function. In line with this, current regulations governing the eligibility of SS patients within subsidized dental care programs should be reviewed.