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Objectives: This pilot study aimed to assess dimensional changes following two different alveolar socket sealing techniques. Material and methods: Twenty-one patients requiring tooth extraction and implant placement were randomly allocated to two different alveolar ridge preservation techniques. In the control group, demineralized bovine bone mineral (DBBM) and a gingival soft tissue punch were used to fill and seal the socket, whereas in the test group, the extraction socket was filled with DBBM and sealed with a hemostatic gelatin sponge. Digitalized impressions were taken before and 6 months after tooth extraction. The comparison was made on horizontal and vertical dimensional changes. Results: The mean vertical loss was 0.8 ± 0.6 mm for the control group and 0.7 ± 0.5 mm for the test one. No statistical difference was found between groups for the vertical shrinkage. The horizontal dimensional narrowing of the alveolar socket was respectively 7.1/4.0/2.5 mm at levels 1, 3, and 5 mm from a coronal reference level for the control group. The test group showed dimensional changes of 4.8/2.3/1.3 mm at the three different levels, respectively. A significant difference was found at levels 3 and 5 mm. Referring to a visual analog pain scale, patients reported more severe pain in the control group (5.7/10) when compared with the test group (2.8/10). The difference was statistically highly significant (P ≤ 0.001). Conclusions: A significant difference was found between control and test groups regarding the horizontal dimensional changes and the post-operative pain. Clinical relevance: Regarding this primary result, the socket sealing technique with a hemostatic sponge provides an effective and inexpensive protocol with less post-operative pain. [ABSTRACT FROM AUTHOR]

The purpose of this 4-day plaque regrowth study was to assess the effect of N-chlorotaurine (NCT) mouth rinses on plaque inhibition and plaque vitality. Eighty volunteers participated in this investigator-blind, randomized, clinical controlled study in parallel groups. No oral hygiene was permitted except rinsing with a 2% or 3% NCT mouth rinse, a positive or a negative control. Primary parameters were the plaque index (Silness and Löe, Acta Odontol Scand, 22:121–135, ) and plaque vitality (Netuschil et al., J Clin Periodontol, 16:484–488, ) after the final rinse. In addition, another plaque index (Turesky et al., J Periodontol, 41:41–43, ), plaque area, and bleeding on probing were recorded. All parameters were taken at baseline and day 5. U test was applied on a 5% error level. No differences in plaque inhibition were found between the two NCT formulations and the negative control. However, a statistically significant reduction of plaque vitality compared to the negative and positive control was observed. Discoloration of the tongue and unpleasant taste were recorded in participants in the NCT groups. NCT mouth rinses did not inhibit plaque regrowth, but they did reduce the vitality of plaque bacteria. Methods of prolonging the substantivity of the NCT mouth rinses should be investigated to enhance the antibacterial properties of these formulations. [ABSTRACT FROM AUTHOR]

The aim of the present study was to compare newly formed cementum following different types of regenerative therapy in humans. Eighteen patients, each displaying one advanced intrabony defect around teeth scheduled for extraction, were included in this study. The defects were treated with either guided tissue regeneration (GTR), enamel matrix protein derivative (EMD), EMD plus bioactive glass, bovine-derived xenograft (BDX), BDX plus GTR, or BDX plus EMD. After healing, the teeth were removed together with their surrounding soft and hard tissues. Cellular content, presence of artifactual splits between the new cementum and the old one or the dentin surface, and thickness of the new cementum were evaluated. Irrespective of treatment, the new cementum was of a reparative, cellular, extrinsic and intrinsic fiber type. There were no differences in cementum thickness among treatments. These findings indicate that in humans, (a) the new cementum formed after different types of regenerative therapy was, irrespective of the treatment, of a reparative, cellular, extrinsic and intrinsic fiber type, and (b) the regenerative modality does not seem to influence the type of newly formed cementum. [ABSTRACT FROM AUTHOR]

Application of enamel matrix protein derivative (EMD) onto a debrided and conditioned root surface has been shown to promote periodontal regeneration in animals and humans. However, until now there is virtually no information from humans describing the expression of different matrix molecules in the newly formed periodontal tissues following treatment with EMD. This study investigated immunohistochemically in humans the expression of matrix molecules associated with periodontal tissues reformed after treatment with EMD. Eight patients with intrabony defects were treated with EMD. Six months after surgery teeth together with some of their surrounding soft and hard tissues were removed, fixed in buffered formalin, decalcified in EDTA, and embedded in paraffin. Serial sections of 6 µm were cut in mesiodistal direction. Sections were evaluated immunohistochemically by means of polyclonal antibodies against osteopontin, collagen I and collagen III. The original (non-treated) parts of the periodontium served as controls. In all specimens the healing resulted to a varying extent in formation of cementum, periodontal ligament and alveolar bone. In all specimens the expression of the investigated matrix molecules was stronger at the reformed than at the original sites. Osteopontin expression was most intense at the border near the newly formed cementum and bone. In the regenerated periodontal ligament, collagen I and III were localized throughout the entire periodontal ligament connective tissue. Within the newly formed PDL connective tissue the immunohistochemical staining appeared stronger for collagen III than for collagen I. The present findings suggest that (a) treatment of human intrabony defects with EMD creates an environment favourable for periodontal regeneration and, (b) in humans the healing and/or remodelling process of the reformed tissues may be followed immunohistochemically for a period of 6 months. [ABSTRACT FROM AUTHOR]

The effect of chlorhexidine (CHX) on the viability of Streptococcus sanguinis was investigated in a preclinical biofilm model separately on cells in the planktonic or attached life form. Saliva-coated human enamel and glass slides were exposed to the streptococci suspended in sterile saliva for 30 min and 60 min in the flow chamber system. The CHX exposition was performed in two parts: pretreatment of the planktonic bacteria before their attachment to enamel or glass, and treatment of bacteria already attached to enamel. The susceptibility measured by vitality percentages was determined by fluorescence microscopy using vital/dead cells. After CHX pretreatment of planktonic cells, the mean values of the vitality percentages after adhesion were 14–18% (enamel) and 24–25% (glass). In contrast, the mean vitality percentages of untreated attached streptococci reached 70–75% (enamel) and 68% (glass). The vitality percentages of CHX-exposed bacteria dropped markedly to 2–5%, whereas those of untreated attached cells remained at 65–66%. The exposure of initially attached streptococci to CHX resulted in greater reduction of bacterial viability than with the planktonic counterparts. This preclinical biofilm model allows the investigation of various bacterial life forms and can furthermore be used to select efficient antiplaque therapeutics which might be beneficial for clinical plaque control. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate immunohistochemically the expression of matrix molecules associated with periodontal tissues reformed after regenerative periodontal treatment. Chronic intrabony defects were treated with guided tissue regeneration, enamel matrix proteins, the combination of both, or access flap surgery. Five months after healing, the animals were killed, and the healed periodontal tissues were evaluated immunohistochemically by means of polyclonal antibodies against osteopontin, collagen I, and collagen III. The intact (nontreated) parts of the periodontium served as controls. As a general observation, the staining for all investigated matrix molecules appeared to be stronger within the regenerated tissues than in the intact ones. The results failed to reveal any differences in terms of staining intensity or distribution pattern of investigated matrix molecules between the four different treatments. Osteopontin expression was most intense at the border near the newly formed cementum and bone. In the regenerated periodontium, collagens I and III were localized throughout the entire periodontal ligament connective tissue. In the regenerated periodontal ligament, collagen III displayed more intense staining than collagen I. The present results suggest that: (1) even after a 5-month period following surgical periodontal therapy, extracellular matrix molecules associated with wound healing and/or remodelling are more strongly expressed in regenerated than in intact tissues and (2) once an environment for periodontal regeneration has been created, the expression of extracellular matrix molecules associated with the healing process seems to display the same pattern, irrespective of treatment modality. [ABSTRACT FROM AUTHOR]

The aim of this double-blind, 28-week study was to evaluate the plaque-inhibitory and antigingivitis efficacy of a fluoride toothpaste containing 0.3% triclosan and essential oil (Dental Kosmetik, Dresden, Germany) in comparison with a control toothpaste. One hundred twenty subjects previously treated for chronic periodontitis were included in the study. At baseline, 8, 18, and 28 weeks, plaque accumulation (PlI) and gingival status (GI) were assessed . Probing pocket depth (PD) and bleeding on probing (BOP) were measured at baseline and week 28 using a Florida probe. No professional hygiene was delivered during the study period. Mean plaque scores decreased between baseline and week 8 in both groups. At the end of the study, a significant increase of mean PlI compared to baseline could be observed in the test and in the control groups. Comparing the two groups, the PlI in the triclosan group was significantly lower than in the control group. Mean gingival scores decreased significantly during the first 8-week period in both groups. This reduction was followed by an increase of GI in the control, while the GI in the test group reached a significantly lower value than in controls after 28 weeks. Furthermore, at week 28, in both groups the PD were decreased as compared to the prestudy data. It is concluded that the triclosan/essential oil additive in a fluoride-containing dentifrice exhibited distinctive antigingivitis as well as plaque-inhibitory effects during a 28-week maintenance period in periodontitis patients. [ABSTRACT FROM AUTHOR]

The aim of this randomized, parallel-group, placebo-controlled, blind clinical study was to examine the dental plaque and the gingivitis inhibitory effects of two low-dose 0.06% chlorhexidine (CHX) preparations in comparison to a commercially available 0.1% CHX solution, an amine fluoride/stannous fluoride (ASF) solution and a water control as an adjunct to the daily mechanical oral-hygiene measures. After prophylaxis, 81 medical students performed their tooth cleaning and were asked to rinse for 30 s, according to the instructions given by the manufacturers with the assigned amount of the following solutions: once daily 10 ml ASF 250 ppm or twice daily each 10 ml CHX 0.06% with fluoride, 10 ml CHX 0.06% without fluoride, 15 ml CHX 0.1% or 100 ml tap water. The plaque index (PlI), the gingival index (GI) and the discoloration index (DI) were taken at day –14 and months (M) 0, 1, 2, 3 and 6. In this study group with good oral hygiene, all test products led to a reduction of the PlI scores when used as supplements to the usual mechanical hygiene measures. At M3 subjects using both the 0.1% as well as the 0.06% CHX showed significantly less plaque accumulation than those using ASF. In the GI a significant difference between the control and 0.1% CHX was found at M3 and at M6. If a further decrease in the GI is wanted, a minimum concentration of 0.1% CHX for long-term use in association with habitual cleaning is needed, which, however, should be limited to special patients. If maintaining clinical health is the goal, the other solutions are a good alternative to 0.1% CHX because they exhibit less staining. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate histologically in monkeys the healing in acute fenestration-type defects following treatment with guided tissue regeneration (GTR) or enamel matrix proteins (EMD). Standardized ”critical size” fenestration-type defects were produced surgically at the vestibular aspect of teeth 13, 23, 33, 43 in three monkeys (Macaca fascicularis). The vestibular bone plates were removed and the root surfaces were debrided by means of hand instruments in order to completely remove the root cementum. Following root conditioning with ethylenediaminetetraacetate (EDTA), the defects were treated using one of the following therapies: (1) GTR, (2) EMD, or (3) control (coronally repositioned flaps). After 5 months the animals were killed and perfused with 10% buffered formalin for fixation. Specimens containing the defects and surrounding tissues were dissected free, decalcified in EDTA, and embedded in paraffin. Eight-micrometer-thick step serial histological sections were cut in a vestibulo-oral direction, stained with hematoxylin and eosin or oxone-aldehyde-fuchsin-Halmi, and subsequently examined under the light microscope. The results showed that, in the defects treated with GTR, a new connective tissue attachment (i.e., new cementum with inserting collagen fibers) and new bone formation had consistently occurred, whereas, in the defects treated with EMD or with coronally repositioned flaps, new attachment and new bone reformed to a varying extent. The quality of the cementum did not differ after EMD, GTR, or flap surgery. It was concluded that GTR treatment with bioresorbable membranes seems to predictably promote new attachment and new bone formation, whereas the application of EDTA or EMD may also enhance periodontal healing to a certain extent. Further studies with higher numbers of animals and defects are needed in order to definitely clarify the effect of root surface conditioning with EDTA and EMD on periodontal healing. [ABSTRACT FROM AUTHOR]

The object of this study was to monitor the proportion of vital bacteria (microbial vitality: VF in %) present in subgingival dental plaque following one single subgingival irrigation with saline (S), chlorhexidine (CHX) or povidone iodine (I2), but without any subgingival instrumentation. Its effect on the main composition of the microflora was also assessed. Seventeen patients with adult periodontitis took part in this investigation. In each patient four initially untreated pockets (pocket depth 5–11 mm) associated with bleeding were selected for the standardised pocket irrigation and plaque sampling at baseline (0 h) and after the following 1 h, 24 h, 7 days and 31 days. The subgingival irrigation was only performed once (0 h). One pocket per quadrant was irrigated using 0.9% prereduced S, 0.2% CHX or 0.05% I2 (Iso-Betadine Buccale). The remaining untreated pocket without any irrigation served as an additional control (C). Using an acrylic splint as a guide, paperpoints were inserted into the pocket precisely at the same site to collect subgingival plaque. The bleeding on sampling (BOS) was thereafter noted. The proportions of bacterial morphotypes were examined by darkfield microscopy. VF was evaluated using a vital fluorescence staining. The undisturbed subgingival dental plaque was composed of 86% (median value) vital bacteria. The sampling procedure alone and the saline irrigation led to a decrease in the number of spirochetes but had no influence on the vitality of the flora. Large variations in VF could be observed in the short-term (1 h, 24 h) irrigation effect of CHX and I2. The reduction of VF was still significant after 7 days (VFCHX 30–80%, VFI2 35–80%) but persisted up to 31 days only after I2 irrigation (VFI2 12–90%). The findings indicated that all single subgingival irrigations resulted in a temporary change of the subgingival microflora while povidone iodine produced the longest lasting antimicrobial effect. Any clinical advantage of this situation should be further investigated. [ABSTRACT FROM AUTHOR]