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Buccal Aspect (buccal + aspect)
Selected AbstractsEvaluation of canal filling after using two warm vertical gutta-percha compaction techniques in vivo: a preliminary studyINTERNATIONAL ENDODONTIC JOURNAL, Issue 7 2006M. Venturi Abstract Aim, To evaluate the quality of root canal filling when comparing two warm gutta-percha filling techniques in vivo. Methodology, Human teeth were randomly divided into two equal groups, with 30 canals each. The root canals were shaped by hand and ProFile 0.04 rotary instruments to size 20,40 at the end-point and then filled with gutta-percha cones and AH-Plus. In group A, a traditional warm vertical compaction technique was performed using the Touch'n Heat, and back-filling with the Obtura II. In group B, a modified warm vertical compaction technique was used: small amounts of gutta-percha were removed, and the remaining most apical 3 mm were compacted with a 1 mm movement; then thermomechanical back-filling was performed. The teeth were extracted, stored in dye, cleared, and the distance between the apex and apical limit of the filling, linear dye penetration, and voids were measured from the buccal, lingual, mesial and distal perspective. The homogeneity of variance and means was verified using Levene's test and t -test. anova and Dunnett post hoc test were used to establish the significance and to analyse the effects through multiple comparisons. Results, Compared with the specimens of group A, the specimens of group B exhibited less mean linear dye penetration (P < 0.05), smaller void length (P , 0.05) and maximal width (P , 0.05) when examined in all four views, and a more precise filling when viewed from the buccal aspect (P < 0.05). Conclusions, The modified warm vertical compaction technique with apical back-filling produced a more effective and precise three-dimensional filling. [source] Hard tissue alterations after socket preservation with additional buccal overbuilding: a study in the beagle dogJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 10 2009Stefan Fickl Abstract Objectives: The aim of this study was to histometrically assess alterations of the ridge following socket preservation alone and socket preservation with additional buccal overbuilding. Material and Methods: In five beagle dogs four extraction sites were randomly subjected to one of the following treatments: Tx 1: The socket was filled with BioOss Collagen® and covered with a free gingival graft from the palate. Tx 2: The buccal bone plate was augmented using the GBR-technique, the socket was filled with BioOss Collagen® and covered with a free gingival graft. Tx 3: The buccal bone plate was forced into a buccal direction using a manual bone spreader. The socket was filled with BioOss Collagen® and covered with a free gingival graft from the palate. Tx 4: The socket was filled with BioOss Collagen® and a combined free gingival/connective tissue graft was used to cover the socket and for buccal tissue augmentation. For each experimental site, two histological sections were subjected to histometric analysis and evaluated for (i) vertical bone dimensions and (ii) horizontal bone dimensions. Results: All treatment groups showed horizontal and vertical bone loss. The mean vertical bone loss of the buccal bone plate was significantly lower in Tx 4 than in the other groups, while no statistical significant differences could be detected among the groups in the horizontal dimension. Conclusion: Overbuilding the buccal aspect in combination with socket preservation does not seem to be a suitable technique to compensate for the alterations after tooth extraction. [source] Stability of crestal bone level at platform-switched non-submerged titanium implants: a histomorphometrical study in dogsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 6 2009Jürgen Becker Abstract Objectives: To investigate the influence of platform switching on crestal bone level changes at non-submerged titanium implants over a period of 6 months. Material and Methods: Titanium implants (n=72) were placed at 0.4 mm above the alveolar crest in the lower jaws of 12 dogs and randomly assigned to either matching or non-matching (circumferential horizontal mismatch of 0.3 mm) healing abutments. At 4, 8, 12, and 24 weeks, dissected blocks were processed for histomorphometrical analysis. Measurements were made between the implant shoulder (IS) and the apical extension of the long junctional epithelium (aJE), the most coronal level of bone in contact with the implant (CLB), and the level of the alveolar bone crest (BC). Results: At 24 weeks, differences in the mean IS,aJE, IS,CLB, and IS,BC values were 0.2 ± 1.2, 0.3 ± 0.7, and 0.3 ± 0.8 mm at the buccal aspect, and 0.2 ± 0.9, 0.3 ± 0.5, and 0.3 ± 0.8 mm at the lingual aspect, respectively. Comparisons between groups revealed no significant differences at either the buccal or the lingual aspects. Conclusions: It was concluded that (i) bone remodelling was minimal in both groups and (ii) platform switching may not be of crucial importance for maintenance of the crestal bone level. [source] Influence of platform switching on crestal bone changes at non-submerged titanium implants: a histomorphometrical study in dogsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 12 2007Jürgen Becker Abstract Objectives: The aim of the present study was to investigate histomorphometrically the influence of platform switching on crestal bone changes at non-submerged wide-body titanium implants in a dog model. Material and Methods: One-stage insertion of sand-blasted and acid-etched screw-type implants with either matching (CAM) or smaller-diameter healing abutments (CPS) were randomly assigned to the lower jaws of nine beagle dogs. The animals were killed after 7, 14, and 28 days of non-submerged healing. Dissected blocks were processed for histomorphometrical analysis. Measurements were made between the implant shoulder (IS) and: , the apical extension of the long junctional epithelium (aJE), , the most coronal level of bone in contact with the implant (CLB), and , the level of the alveolar bone crest (BC). Results: At 7, 14, and 28 days, the mean IS,aJE values were significantly the lowest at CPS implants. However, after 28 days of healing, both groups revealed significantly increased mean IS,BC values at the buccal aspect of the alveolar bone. The difference in IS,CLB and IS,BC between groups was not significant. Conclusions: Within the limits of the present study, it was concluded that both CAM and CPS implants revealed crestal bone-level changes after 28 days of healing. [source] Investigation of the factors related to the formation of the buccal mucosa ridgingJOURNAL OF ORAL REHABILITATION, Issue 6 2003I. Takagi summary, The aim of this study was to clarify the factors related to the formation of the buccal mucosa ridging, which has been mentioned to be a clinical sign of clenching. Twenty-one individuals were investigated and divided into three groups: (i) those without buccal mucosa ridging, (ii) the buccal mucosa ridging located in all the posterior teeth region, and (iii) the buccal mucosa ridging corresponding only to the molar teeth region. A pressure sensor was used and placed at two points: first upper premolar and second upper molar. The recording tasks were: (i) silent reading at rest, (ii) light voluntary clenching, (iii) maximum voluntary clenching, (iv) holding the cheeks tightly against the teeth while light voluntary clenching, (v) holding the cheeks tightly against the teeth without tooth contact, (vi) pulling angle of mouth laterally while light voluntary clenching, (vii) pulling angle of mouth laterally without tooth contact and (viii) swallowing. No significant differences were found between groups in all the recording tasks except for the swallowing, at which significant difference (P < 0·05) was found between the groups of individuals having buccal mucosa ridging and without it. Based on these results it became clear that the buccal mucosa pressure exerted on the buccal aspect of teeth during swallowing plays an important role in the formation of buccal mucosa ridging. [source] The acute effects of smokeless tobacco (snuff) on gingival blood flow in manJOURNAL OF PERIODONTAL RESEARCH, Issue 4 2001Antonios Mavropoulos Snuff-induced blood flow responses in the gingiva were evaluated in 22 healthy casual consumers of tobacco. Laser Doppler flowmetry (LDF) was used to measure blood flow simultaneously and continuously on two gingival sites (buccal aspect of the papillae between the upper lateral incisors and canines). In addition, measurements of skin blood flow in the forehead and palmar side of the left thumb were performed. Arterial blood pressure (BP) and heart rate (HR) were also recorded. Unilateral application of commercial snuff (500 mg, 1%) caused a marked and rapid increase in gingival blood flow (GBF) on the exposed side (p<0.001). Blood flow increased also in the contralateral gingiva and forehead skin (p<0.05). Skin blood flow in the thumb showed an insignificant decrease. BP and HR increased. Vascular conductance increased significantly in the snuff-exposed gingiva but not in the contralateral gingiva or the forehead. Vascular conductance was largely unaffected in the thumb. It is concluded that acute application of snuff, besides giving rise to typical changes in BP and HR, increases GBF in and around the exposed area, probably through activation of sensory nerves and the subsequent release of vasodilatory peptides from their peripheral endings. Blood flow in unexposed gingival and forehead skin may increase probably due to humoral or nervously mediated mechanisms. However, a passive pressure-induced hyperaemia in the unexposed gingiva and forehead skin can not be excluded. [source] Precision of Fit of Two Margin Designs for Metal-Ceramic CrownsJOURNAL OF PROSTHODONTICS, Issue 4 2007Penwadee Limkangwalmongkol DDS Statement of Problem: Although metal-ceramic restorations are widely used, there is a lack of information about how the fit is affected by margin designs. Purpose: This study measured and compared the precision of fit of metal-ceramic crowns with two margin designs. Material and Methods: Thirty-two extracted human premolar teeth were prepared for complete-coverage restorations with an internally rounded shoulder preparation. Impressions were made from all teeth, and master dies were poured with improved stone type V. MC crowns were fabricated with a porcelain-butt margin on the buccal aspect (n = 32) and a feather-edge metal margin on the lingual aspect (n = 32), which served as a control group. Precision of fit was measured three times at the mid-buccal and mid-lingual margins of each crown with a profilometer. The data were statistically analyzed with the paired t -test (, < .05). Results: Mean marginal gap size of porcelain-butt margins was 27.93 ,m (±15.84) and of feather-edge metal margins 42.43 ,m (±24.12). The marginal gap size of feather-edge metal margins was statistically significantly greater than that of porcelain-butt margins (p = 0.0045). Conclusion: The marginal fit of porcelain-butt margins was significantly better than that of feather-edge metal margins. Clinical Implications: Porcelain-butt margins in this study had a better marginal fit than feather-edge metal margins, and thus have given clinicians evidence to prefer the use of porcelain-butt margins. [source] Collagen membranes at immediate implants: a histomorphometric study in dogsCLINICAL ORAL IMPLANTS RESEARCH, Issue 9 2010Marco Caneva Abstract Aim: To evaluate the influence of resorbable membranes on hard tissue alterations and osseointegration at implants placed into extraction sockets in a dog model. Material and methods: In the mandibular premolar region, implants were installed immediately into the extraction sockets of six Labrador dogs. Collagen-resorbable membranes were placed at the test sites, while the control sites were left uncovered. Implants were intended to heal in a submerged mode. After 4 months of healing, the animals were sacrificed, and ground sections were obtained for histomorphometric evaluation. Results: After 4 months of healing, a control implant was not integrated (n=5). Both at the test and at the control sites, bone resorption occurred. While the most coronal bone-to-implant contact was similar between the test and the control sites, the alveolar bone crest outline was maintained to a higher degree at the buccal aspect of the test sites (loss: 1.7 mm) compared with the control sites (loss: 2.2 mm). Conclusions: The use of collagen-resorbable membranes at implants immediately placed into extraction sockets contributed to a partial (23%) preservation of the buccal outline of the alveolar process. To cite this article: Caneva M, Botticelli D, Salata LA, Souza SLS, Carvalho Cardoso L, Lang NP. Collagen membranes at immediate implants: a histomorphometric study in dogs. Clin. Oral Impl. Res. 21, 2010; 891,897. doi: 10.1111/j.1600-0501.2010.01946.x [source] Lateral ridge augmentation using particulated or block bone substitutes biocoated with rhGDF-5 and rhBMP-2: an immunohistochemical study in dogsCLINICAL ORAL IMPLANTS RESEARCH, Issue 7 2008Frank Schwarz Abstract Objectives: The aim of the present study was to immunohistochemically evaluate lateral ridge augmentation using a particulated (BOG) or block (BOB) natural bone mineral biocoated with rhGDF-5 and rhBMP-2 in dogs. Materials and methods: Three standardized box-shaped defects were surgically created at the buccal aspect of the alveolar ridge in each quadrant of eight beagle dogs. After 2 months of healing, the chronic-type defects were randomly allocated in a split-mouth design to either (i) BOG or (ii) BOB biocoated with (a) rhGDF-5 or (b) rhBMP-2, respectively. Uncoated grafts served as controls. After 3 and 8 weeks, dissected blocks were prepared for immunohistochemical [osteocalcin (OC)] and histomorphometrical analysis [e.g. area (mm2) of new bone fill (BF), newly formed mineralized (MT) and non-mineralized tissue (NMT)]. Results: rhBMP-2 biocoated BOG revealed significantly highest BF and MT values at 3 (upper and lower jaws , UJ/LJ , compared with BOG) and 8 weeks (UJ , compared with rhGDF-5). Biocoating of BOB using both rhGDF-5 and rhBMP-2 resulted in significantly increased MT values at 8 weeks (UJ/LJ , compared with BOB). In all groups, NMT adjacent to BOG and BOB scaffolds revealed pronounced signs of an OC antigen reactivity. Conclusions: Within the limits of the present study, it was concluded that both rhGDF-5 and rhBMP-2 have shown efficacy; however, their bone regenerative effect was markedly influenced by the carrier. [source] Modeling of the buccal and lingual bone walls of fresh extraction sites following implant installationCLINICAL ORAL IMPLANTS RESEARCH, Issue 6 2006Mauricio G. Araújo Abstract Objective: To determine whether the reduction of the alveolar ridge that occurs following tooth extraction and implant placement is influenced by the size of the hard tissue walls of the socket. Material and methods: Six beagle dogs were used. The third premolar and first molar in both quadrants of the mandible were used. Mucoperiostal flaps were elevated and the distal roots were removed. Implants were installed in the fresh extraction socket in one side of the mandible. The flaps were replaced to allow a semi-submerged healing. The procedure was repeated in the contra later side of the mandible after 2 months. The animals were sacrificed 1 month after the final implant installation. The mandibles were dissected, and each implant site was removed and processed for ground sectioning. Results: Marked hard tissue alterations occurred during healing following tooth extraction and implant installation in the socket. The marginal gap that was present between the implant and the walls of the socket at implantation disappeared as a result of bone fill and resorption of the bone crest. The modeling in the marginal defect region was accompanied by marked attenuation of the dimensions of both the delicate buccal and the wider lingual bone wall. Bone loss at molar sites was more pronounced than at the premolar locations. Conclusion: Implant placement failed to preserve the hard tissue dimension of the ridge following tooth extraction. The buccal as well as the lingual bone walls were resorbed. At the buccal aspect, this resulted in some marginal loss of osseointegration. [source] | ||||||||||