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Bone Level (bone + level)
Kinds of Bone Level Terms modified by Bone Level Selected AbstractsMarginal Bone Level around Implants Assessed in Digital and Film Radiographs: In Vivo Study in the DogCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2000Eva Borg DDS ABSTRACT Background: One of the objectives of postoperative radiographic examinations of implants is to evaluate the marginal bone height and its changes over time. Purpose: The purpose of this study was to assess the influence of digital image processing on measurements of the marginal bone level around implants. Material and Methods: Implants in beagle dogs, used to study the development of peri-implantitis and subsequent healing following treatment, were monitored with conventional radiography and a digital image plate system. Five observers measured the distance between a reference point and the bone level. Measurements in conventional radiographs were made with the use of an x-ray viewer (2X) and a magnifying lens (7X). For the digital images, the system's built-in measuring function was used together with five image processing techniques: edge enhancement (matrixes set on 5 and 25), inverted grey scale, single color highlight, and color intensity mapping together with the brightness and contrast control. From the time of maximum breakdown and the end of the experiment, histologic values were available. Results: Differences between techniques and observers increased toward the end of the healing period. Measurements made at maximum breakdown did not differ significantly from the histologic value. Measurements made after healing all methods, except that using edge enhancement and a 25 × 25 kernel, differed significantly from the histologic value by underestimating the bone level. Conclusions: Measurements of bone level around implants from digital radiographs are as accurate and precise as those from film images. In particular cases, the use of specific image processing algorithms may improve both accuracy and precision. After healing, the histologic specimens showed an incomplete bone fill in the crater with a remaining thin layer of connective tissue in contact with the fixture, and in such situations, the morphology of the bone will give a more complicated diagnostic task. [source] Early Loading of Four or Five Astra Tech Fixtures with a Fixed Cross-Arch Restoration in the MandibleCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2002Bruno Collaert DDS ABSTRACT Background: A change in implant placement has emerged recently from two-stage to one-stage surgery and to earlier and even immediate loading of the fixtures. Purpose: The aim of this study was to verify whether four or five fixtures installed in the edentulous mandible were suitable for early loading with a cross-arch fixed restoration. Materials and Methods: In 25 consecutively treated patients (28,88 yr), four or five Astra Tech fixtures (Mölndal, Sweden) were installed in edentulous mandibles. During the same surgical procedure, the abutments were connected. An impression was taken immediately after surgery. All patients received a fixed prosthetic rehabilitation of 10 to 12 teeth made of a cast metal framework and acrylic teeth/gingiva within a month. The fixtures were followed up clinically and radiographically for 7 to 24 months. Bone level was measured from the most coronal point of the vertical part of the fixture to the most apical bone level mesially or distally. Results: No fixtures were lost during follow-up. No postoperative complications occurred. Radiographic analysis showed a mean bone level of 0.6 mm after 7 to 12 months. Fixtures followed up from 13 to 18 and 19 to 24 months showed a mean bone level of 0.7 mm. Around two fixtures, the bone level was found at the first implant thread. All other fixtures showed the bone level somewhere along the vertical unthreaded part of the fixture. Conclusions: Early loading within 1 month of four or five Astra Tech fixtures in the edentulous mandible is a predictable procedure for a follow-up period of 6 to 24 months. [source] A Unique Microcracking Process Associated with the Inelastic Deformation of Haversian BoneADVANCED FUNCTIONAL MATERIALS, Issue 1 2009Vincent Ebacher Abstract Since the discovery of the Haversian system in human bone over three hundred years ago, researchers have been wondering about its mechanical advantages. Despite positive experimental evidences on the intervention of Haversian systems in the fracture process, the contributions of Haversian systems to bone fracture have been obscure. Here a unique microcracking process accompanying the inelastic deformation of Haversian bone is reported that may shine light on its structural advantages over other bones. When compressed transversely, the concentric bone lamellae surrounding each Haversian canal allow multiple radial microcracks and arc-shaped cracks to develop intralamellarly. Groups of circumferential arc-shaped microcracks develop in high shear zones and radiate out in oblique directions from each Haversian canal. At the cortical bone level, where the Haversian systems are randomly distributed within the interstitial matrix, multiple nucleations and stable development of such arc-shaped cracks happen to most Haversian systems progressively. As a result, Haversian bone is not sensitive to the presence of Haversian canals and demonstrates high inelastic strains at macroscopic level. [source] Intraoral condition in children with juvenile idiopathic arthritis compared to controlsINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 6 2008EVA LEKSELL Aims. The aims of this study were to compare the periodontal conditions in children and adolescents with juvenile idiopathic arthritis (JIA) in comparison to age-matched healthy individuals, and to describe intraoral health in relation to medical assessments. Design. Forty-one JIA patients, 10,19 years old, were compared to 41 controls. Plaque, calculus, probing depth, bleeding on probing, clinical attachment loss, as well as mucosal lesions were registered. Marginal bone level was recorded on radiographs. A questionnaire was included. Data were analysed with chi-squared test, Fisher's exact test, and Mann,Whitney U -test (P < 0.05). Results. The JIA patients reported pain from jaws (P = 0.001), hands (P = 0.001), and oral ulcers (P = 0.015) more often than controls. They avoided certain types of food because of oral ulcers (P = 0.037). The frequencies of sites with plaque (32% vs. 19%, P = 0.013), calculus (11% vs. 5%, 5 = 0.034), bleeding on probing (26% vs. 14%, P < 0.01), and probing depth 2 mm (32% vs. 2%, P < 0.001) were higher among JIA patients. No sites with attachment loss or reduced marginal bone level were observed. Conclusions. These obtained results are probably because of joint pain, making it difficult to perform oral hygiene as well as the use of medication and general disease activity. [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] Treatment outcome of immediate, early and conventional single-tooth implants in the aesthetic zone: a systematic review to survival, bone level, soft-tissue, aesthetics and patient satisfactionJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 12 2008Laurens Den Hartog Abstract Aim: This study evaluated, through a systematic review of the literature, the outcome of single-implant restorations in the aesthetic zone with natural adjacent teeth, thereby addressing immediate, early and conventional implant approaches. Material and Methods: MEDLINE (1950,2008), EMBASE (1966,2008), and CENTRAL (1800,2008) were searched to identify eligible studies. Two reviewers independently assessed the methodological quality using specific study-design-related assessment forms. Results: Out of 86 primarily selected articles, 19 studies fulfilled the inclusion criteria. A meta-analysis showed an overall survival rate of 95.5% [95% confidence interval: (93.0,97.1)] after 1 year. A stratified meta-analysis revealed no differences in survival between immediate, early and conventional implant strategies. Little marginal peri-implant bone resorption was found together with low incidence of biological and technical complications. No significant differences in outcome measures were reported in clinical trials comparing immediate, early or conventional implant strategies. Conclusion: The included literature suggested that promising short-term results could be achieved for immediate, early and conventional single-implants in the aesthetic zone. However, important parameters as aesthetic outcome, soft-tissue aspects, and patient satisfaction were clearly underexposed. The question whether immediate and early single-implant therapies would result in better treatment outcomes remained inconclusive due to lack of well-designed controlled clinical studies. [source] Correlation between early perforation of cover screws and marginal bone loss: a retrospective studyJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 1 2008Nele Van Assche Abstract Aim: This retrospective study aimed to determine the consequence of early cover screw exposure on peri-implant marginal bone level. Material and Methods: Sixty Astra Tech® MicroThread implants installed in partially edentulous jaws were compared: 20 implants were placed following a two-stage procedure and were unintentionally exposed to the oral cavity (two-stage exposed), 20 implants were placed following a two-stage procedure and were surgically exposed after a subgingival healing time of 3,6 months (two-stage submerged), and 20 implants were placed following a one-stage surgical protocol (one-stage). Digital radiographs were taken at implant placement for all implants, and after abutment surgery for the two-stage exposed and two-stage submerged groups or after 3 months for the one-stage group. Bone loss mesially and distally was measured with an on-screen cursor after calibration. Results: Mean bone re-modelling was 1.96 mm (range: 0.2,3.2 mm) around the two-stage exposed implants, 0.01 mm (range: 0.0,0.3 mm) around the two-stage submerged implants and 0.14 mm (range: 0.0,1.2 mm) around the one-stage implants. Conclusion: The unintentional perforation of two-stage implants resulted in significant bone destruction, probably because the biological width was not considered. [source] The extent of periodontal disease and the IL-6,174 genotype as determinants of serum IL-6 levelJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 12 2007Taina Raunio Abstract Aim: To study the extent of periodontal disease and the IL-6,174 genotype as determinants of serum and mouthwash IL-6 concentration in subjects with moderate to severe periodontal disease. Material and Methods: Fifty-two generally healthy subjects volunteered to participate. Probing pocket depth (PD) and periodontal attachment level (AL) were clinically examined and alveolar bone level (BL) was measured on orthopantomographs. IL-6 concentrations in mouthwash, collected by rinsing with 3 ml saline for 30 s and in serum, obtained by venipuncture, were measured using ELISA. IL-6,174 polymorphism was studied using a polymerase chain reaction. Results: Eleven subjects carried the GG genotype, and 41 subjects, carried the CG/CC genotype. The mean (± SD) concentration of IL-6 in serum was 1.6 (± 1.5) pg/ml and, 2.8 (± 5.04) pg/ml in mouthwash. The serum concentration of IL-6 was higher in subjects with the GG genotype than with the CG/CC genotype. In regression analyses the percentages of sites with PD6 mm, AL6 mm and BL8 mm, the IL-6,174 genotype, body mass index and gender associated significantly with serum IL-6 concentration. Conclusions: The extent of moderate to severe periodontal disease and the IL-6,174 genotype contribute significantly to serum IL-6 concentration. [source] Astra Tech single-tooth implants: an audit of patient satisfaction and soft tissue formJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 7 2007R. M. Palmer Abstract Aim: To investigate patient centred outcomes, soft tissue morphology, and bone levels. Material and Methods: Sixty-six subjects, who had completed treatment for a single implant restoration at least l year previously. Appearance was recorded photographically and bone levels and interdental contact points measured from intra-oral radiographs using a × 7 scale loupe. Subjects completed a satisfaction questionnaire. Results: Subjects were highly satisfied with all aspects of the restoration including the appearance of the soft tissue (median shape/colour score 6 on scale 1,6). Twenty-eight sites in 20 subjects had no contact point between implant crown and adjacent tooth. A normal height papilla was judged to be present in 19 of these sites. These were excluded from the subsequent analysis. In the remaining 46 subjects with contact points the presence (JEMT score 3) or deficiency (score 1/2) of the papilla was significantly related to the distance to the bone level on the adjacent tooth and implant head. Differences were observed between the mesial and distal aspects of the implant restoration. Conclusions: Examining clinicians were more critical of the restorations than the patients. The presence of a complete papilla was associated with a slightly greater distance from contact point to bone level than previously reported. [source] Periodontal conditions in male adolescents using smokeless tobacco (moist snuff)JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 12 2006Ulrika Montén Abstract Aim: The aim of this study was to evaluate the potential association of the use of smokeless tobacco (moist snuff) on the periodontal conditions of adolescents. Material and methods: A subject sample of one hundred and three 19-year-old male individuals (33 snuff users, 70 controls) living in Göteborg, Sweden, were clinically examined with regard to oral hygiene, gingivitis, probing pocket depth (PPD), clinical attachment loss (CAL) and gingival recession. Bitewing radiographs were obtained for assessments of alveolar bone level. Information about tobacco and oral hygiene habits was obtained by a structured questionnaire. Student 's t -test, ,2 -test and logistic regression analysis were used for statistical analysis. Results: The mean plaque and gingivitis scores in snuff-users were 59% (SD 21.0) and 47% (18.6), respectively, and in controls 64% (22.4) and 50% (18.3), respectively. The average PPD and CAL in snuff-users amounted to 2.3 mm (0.3) and 0.2 mm (0.1), respectively, and in controls 2.4 mm (0.3) and 0.1 mm (0.1) (p>0.05), respectively. The mean bone level was 1.3 mm (0.2) in both groups. The prevalence of subjects showing recession was 42% among snuff-users and 17% among controls (p=0.006). In snuff users, an average of 4% (0.9) of the teeth showed recession, compared with 1% (0.3) in controls (p<0.001). Limiting the analysis to the maxillary anterior tooth region, 33% of the snuff-users and 10% of the controls presented recessions (p=0.002). The use of snuff entailed an OR=5.1 to have gingival recessions. Conclusion: In the present population sample of adolescents, the use of smokeless tobacco (moist snuff) was not associated with the presence of periodontal disease except for a significantly high prevalence of gingival recessions. [source] Deproteinized bovine bone and gentamicin as an adjunct to GTR in the treatment of intrabony defects: a randomized controlled clinical studyJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 6 2003A. Stavropoulos Abstract Objectives: To evaluate whether Bio-Oss® used as an adjunct to guided tissue regeneration (GTR) improves the healing of 1- or 2-wall intrabony defects as compared with GTR alone, and to examine whether impregnation of Bio-Oss® with gentamicin may have an added effect. Material and methods: Sixty patients, with at least one interproximal intrabony defect with probing pocket depth (PPD) 7 mm and radiographic evidence of an intrabony component (IC) 4 mm, were treated at random with either a resorbable membrane (GTR), a resorbable membrane in combination with Bio-Oss® impregnated with saline (DBB,), a resorbable membrane in combination with Bio-Oss® impregnated with gentamicin (DBB+), or with flap surgery (RBF). Results: All treatment modalities resulted in statistically significant clinical improvements after 1 year. Defects treated with GTR alone presented a probing attachment level (PAL) gain of 2.9 mm, a residual PPD (PPD12) of 4.9 mm, a radiographic bone level (RBL) gain of 3.1 mm, and a residual IC (IC12) of 2.7 mm. GTR combined with Bio-Oss® did not improve the healing outcome (PAL gain: 2.5 mm; PPD12: 4.9 mm; RBL gain: 2.8 mm; IC12: 3.3 mm). Impregnation of the Bio-Oss® with gentamicin 2% mg/ml resulted in clinical improvements (PAL gain: 3.8 mm; PPD12: 4.2 mm; RBL gain: 4.7 mm; IC12: 2.1 mm), superior to those of the other treatment modalities, but the difference was not statistically significant. Defects treated with only flap surgery showed the most inferior clinical response (PAL gain: 1.5 mm; PPD12: 5.1 mm; RBL gain: 1.2 mm; IC12: 4.2 mm) of all groups. Conclusion: The results failed to demonstrate an added effect of Bio-Oss® implantation in combination with GTR on the healing of deep interproximal 1- or 2-wall, or combined 1- and 2-wall intrabony defects compared with GTR alone. Local application of gentamicin, on the other hand, improved the treatment outcome but not to an extent that it was statistically significant. Zusammenfassung Von Proteinen befreiter boviner Knochen und Gentamycin als Adjuvans der GTR bei der Behandlung von infraalveolären Knochentaschen. Eine randomisierte kontrollierte klinische Studie. Ziele: Die Evaluation ob, Bio-Oss® welches als Adjuvans zur GTR verwendet wird, die Heilung von 1- oder 2-wandigen Knochentaschen im Vergleich zu alleiniger GTR verbessert. Sowie die Untersuchung, ob die Imprägnierung von Bio-Oss® mit Gentamycin einen zusätzlichen Effekt haben könnte. Material und Methoden: 60 mit wenigstens einer approximalen Knochentasche mit Sondierungstiefe (PPD) ,7 mm und röntgenologischem Nachweis einer infraalveolären Komponente (IC) von ,4 mm, wurden randomisiert entweder mit einer resorbierbaren Membran (GTR), einer resorbierbaren Membran in Kombination mit Bio-Oss® welche mit Kochsalzlösung imprägniert war (DBB-), einer resorbierbaren Membran in Kombination mit Bio-Oss® welche mit Gentamycin imprägniert war (DBB+) oder mit Lappen-OP (RPF) behandelt. Ergebnisse: Nach einem Jahr hatten alle Behandlungsweisen eine statistisch signifikante klinische Verbesserung zum Ergebnis. Defekte, die mit alleiniger GTR behandelt wurden zeigten einen Gewinn an klinischem Attachmentniveau (PAL) von 2,9 mm, einer PPD (PPD12) von 4,9 mm, einem Gewinn an röntgenologischem Knochenniveau (RBL) von 3,1 mm und einer IC (IC12) von 2,7 mm. GTR in Kombination mit Bio-Oss® verbesserte das Ergebnis der Heilung nicht (PAL Gewinn: 2,5 mm; PPD12: 4,9; RBL Gewinn: 2,8 mm; IC12: 3,3 mm). Die Imprägnierung von Bio-Oss® mit Gentamycin 2% mg/ml hatte klinische Verbesserungen zum Ergebnis (PAL Gewinn: 3,8 mm; PPD12: 4,2 mm; RBL Gewinn: 4,7 mm; IC12: 2,1 mm), die größer waren als die der anderen Behandlungsweisen, jedoch waren die Unterschiede nicht statistisch signifikant. Defekte, die nur mit Lappen-OP behandelt wurden zeigten das schlechteste klinische Ergebnis von allen Gruppen (PAL Gewinn: 1,5 mm; PPD12: 5,1 mm; RBL Gewinn: 1,2 mm; IC12: 4,2 mm). Schlussfolgerung: Die Ergebnisse konnten im Vergleich mit alleiniger GTR keinen zusätzlichen Effekt der Bio-Oss®-Implantation in Kombination mit GTR hinsichtlich der Heilung von tiefen approximalen 1- oder 2-wandigen oder kombinierten 1- oder 2-wandigen Knochentaschen aufzeigen. Auf der anderen Seite verbessert die lokale Applikation von Gentamycin das Behandlungsergebnis, jedoch war das Ausmaß nicht statistisch signifikant. Résumé Os bovin déprotéiné et gentamicine comme adjuvant à la RTG pour le traitement des lésions intra-osseuses. Une étude clinique contrôlée et randomisée. Objectifs: Evaluer si Bio-Oss® utilisé comme adjuvant de la RTG améliore la cicatrisation des lésions intra-osseuses par rapport à la RTG seule et examiner si l'imprégnation de Bio-Oss® avec de la gentamicine pourrait avoir un effet supplémentaire. Matériels et Méthodes: 60 patients, présentant au moins une lésion intra-osseuse interproximale avec une profondeur de poche au sondage (PPD) ,7 mm et la présence avérée radiologiquement d'une composante intra-osseuse (IC) ,4 mm, ont été traités au hasard avec soit une membrane résorbable (GTR), une membrane résorbable en combinaison avec du Bio-Oss® imprégné de solution saline (DBB-), une membrane résorbable en combinaison avec du Bio-Oss® imprégné de gentamicine (DBB+), ou par chirurgie à lambeau (RBF). Résultats: Toutes les modalités de traitement entraînaient des améliorations cliniques significatives statistiquement après un an. Les lésions traitées par RTG seule présentaient un gain d'attache de 2.9 mm, une PPD résiduelle (PPD12) de 4.9 mm, un gain de niveau osseux radiographique (RBL) de 3.1 mm, et un IC résiduel (IC12) de 2.7 mm. La RTG combinée avec le Bio-Oss® n'améliorait pas le devenir de la cicatrisation. (gain de PAL: 2.5 mm; PPD12: 4.9; gain de RBL: 2.8 mm; IC12: 3.3 mm). L'imprégnation du Bio-Oss®avec la gentamicine (2% mg/ml) apportait des améliorations cliniques (gain de PAL: 3.8 mm; PPD12: 4.2 mm; gain de RBL: 4.7 mm; IC12: 2.1 mm), supérieurs à ceux des autres modalités de traitement, mais la différence n'était pas significative. Le traitement des lésions par lambeaux seulement entraînait la réponse clinique la moins bonne (gain de PAL: 1.5 mm; PPD12: 5.1 mm; gain de RBL: 1.2 mm; IC12: 4.2 mm). Conclusion: Ces résultats ne pouvaient démontrer un effet supplémentaire, sur la cicatrisation de lésions profondes interproximales avec une ou deux parois, de l'implantation de Bio-Oss® en combinaison avec la RTG par rapport à la RTG seule. L'application locale de gentamicine, par contre, améliorait le devenir du traitement mais pas suffisamment pour être statistiquement significatif. [source] Influence of smoking on marginal bone loss and tooth loss , a prospective study over 20 yearsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 8 2002Leif Jansson Abstract Aims:, The aim was to investigate the influence of smoking on longitudinal marginal bone loss and tooth loss in a prospective study over 20 years. In addition, the effect of cessation of smoking on bone loss and the interaction between smoking, plaque and marginal bone loss were evaluated. Material and Methods:, A total of 507 dentate individuals from an epidemiological study were examined in 1970 and 1990. The clinical investigation included registration of number of remaining teeth and presence of plaque. The marginal bone level was determined by assessments on the proximal surfaces on the radiographs from 1970 and 1990. The marginal bone loss was defined as the difference in marginal bone level over 20 years. The subjects were interviewed about smoking habits. Stepwise multiple regression analyses were adopted to calculate the influence of the independent variables on longitudinal marginal bone loss and tooth loss. Results:, In 1970, 50.7% of the subjects were smokers, while the corresponding relative frequency in 1990 had decreased to 31.0%. Smoking was significantly correlated to an increased marginal bone loss over 20 years. Individuals who stopped smoking between 1970 and 1990 lost significantly less marginal bone during this period than those who declared that they smoked during the 20-year period. Smoking was not found to be significantly correlated to tooth loss over 20 years. Conclusions:, The results support the hypothesis that smoking is a significant risk factor of periodontal disease. [source] Analysis of the possibility of the relationship between various implant-related measures: an 18-month follow-up studyJOURNAL OF ORAL REHABILITATION, Issue 2 2008T. F. TÖZÜM Summary, Better clarification of the long-term relationship among the various implant-related measures could improve the evaluation process for dental implants. Thus, the aim of the present study was to determine the potential correlations among the volumetric features and nitric oxide content of peri-implant sulcus fluid (PISF) and measures of implant stability, and the marginal bone loss. Completely edentulous patients (n = 15) treated with dental implants and ball attachment mandibular over dentures were included. Resonance frequency analysis (RFA), marginal bone level measurements, PISF volume and spectrophotometrically determined nitrite levels were recorded for all dental implant sites. Measures for early (n = 16) and delayed (n = 14) loaded dental implants were comparatively analysed for a period of 18 months. Some random correlations between PISF volume and marginal bone level, PISF nitrite level and marginal bone level and PISF volume and PISF nitrite content, and RFA and PISF volume were observed. However, the only constant correlation was noticed between implant stability (RFA scores) and marginal bone level. This correlation was negative and significant for all dental implants and for delayed loaded implants (P < 0·05). The pattern of loading seemed to affect the extent, but not the pattern of this relationship. While some of the implant-related measures may be strongly associated (e.g. dental implant stability and marginal bone level), not all measures from a single implant site are likely to be related. Such associations may be under the influence of a variety of factors including the loading protocol of dental implants. [source] Brief communication: The London atlas of human tooth development and eruptionAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2010S.J. AlQahtani Abstract The aim of this study was to develop a comprehensive evidence-based atlas to estimate age using both tooth development and alveolar eruption for human individuals between 28 weeks in utero and 23 years. This was a cross-sectional, retrospective study of archived material with the sample aged 2 years and older having a uniform age and sex distribution. Developing teeth from 72 prenatal and 104 postnatal skeletal remains of known age-at-death were examined from collections held at the Royal College of Surgeons of England and the Natural History Museum, London, UK (M 91, F 72, unknown sex 13). Data were also collected from dental radiographs of living individuals (M 264, F 264). Median stage for tooth development and eruption for all age categories was used to construct the atlas. Tooth development was determined according to Moorrees et al. (J Dent Res 42 (1963a) 490,502; Am J Phys Anthropol 21 (1963b) 205,213) and eruption was assessed relative to the alveolar bone level. Intraexaminer reproducibility calculated using Kappa on 150 teeth was 0.90 for 15 skeletal remains of age <2 years, and 0.81 from 605 teeth (50 radiographs). Age categories were monthly in the last trimester, 2 weeks perinatally, 3-month intervals during the first year, and at every year thereafter. Results show that tooth formation is least variable in infancy and most variable after the age of 16 years for the development of the third molar. Am J Phys Anthropol, 2010. © 2010 Wiley-Liss, Inc. [source] Sinus Lift Using a Nanocrystalline Hydroxyapatite Silica Gel in Severely Resorbed Maxillae: Histological Preliminary StudyCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2009Luigi Canullo DDS ABSTRACT Purpose: The aim of this preliminary study was to evaluate histologically a nanocrystalline hydroxyapatite silica gel in maxillary sinus floor grafting in severely resorbed maxillae. Materials and Methods: A total of 16 consecutive patients scheduled for sinus lift were recruited during this study. Patients were randomly divided in two groups, eight patients each. In both groups, preoperative residual bone level ranged between 1 and 3 mm (mean value of 2.03 mm). No membrane was used to occlude the buccal window. Second surgery was carried out after a healing period of 3 months in Group 1 and 6 months in Group 2. Using a trephine bur, one bone specimen was harvested from each augmented sinus and underwent histological and histomorphometric analysis. Results: Histological analysis showed significant new bone formation and remodeling of the grafted material. In the cores obtained at 6 months, regenerated bone, residual NanoBone, and bone marrow occupied respectively 48 ± 4.63%, 28 ± 5.33%, and 24 ± 7.23% of the grafted volume. In the specimens taken 3 months after grafting, mean new bone was 8 ± 3.34%, mean NanoBone was 45 ± 5.10%, and mean bone marrow was 47 ± 6.81% of the bioptical volume. Conclusions: Within the limits of this preliminary prospective study, it was concluded that grafting of maxillary sinus using nanostructured hydroxyapatite silica gel as only bone filler is a reliable procedure also in critical anatomic conditions and after early healing period. [source] Clinical Outcome of Overdenture Treatment on Two Nonsubmerged and Nonsplinted Astra Tech MicrothreadÔ ImplantsCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2 2009Hugo De Bruyn DDS ABSTRACT Background: The use of two implants for mandibular overdenture stabilization improves the patients' comfort and well-being. This treatment could be more cost-effective if surgery and prosthetic treatment could be performed by one clinician in the normal setting of a dental clinic. Purpose: The aim of this retrospective clinical study was to describe implant success, restorative outcome, and the patients' opinion of mandibular overdenture treatment on two early-loaded, nonsplinted Astra Tech TiOblast MicrothreadÔ (Astra Tech Dental, Mölndal, Sweden) implants. Materials and Methods: Thirty-seven consecutive patients treated with implant-supported mandibular overdentures were invited for a clinical examination. Implant survival, marginal bone level, quality of implant and prosthetic treatment, and the patients' opinion by means of questionnaires were scored. Results: Thirty-four patients attended the examination. Two implants were lost in one patient and the failure rate for the total group of patients was 3%. As 8 of the 33 remaining patients were still in the provisional loading stage, they were not included in the final clinical and radiographic examination. Based on 25 patients and 50 implants with a mean follow-up of 18.8 months (range 4,33), implant positioning and occlusion/articulation scored perfect in 74 to 80% of the cases. Retention of the dentures was rated perfect in 80%, but 20% needed minor activation of the attachments, 20% showed signs of abrasion, and 20% had already been repaired. The average marginal bone level was 0.8 mm below the reference point. The mean pocket depth was 2.1 mm, and 54% of the peri-implant tissues were free of bleeding. The patients were appreciative of the work carried out by their dentist and they indicated a significant improvement in their well-being and quality of life. Conclusions: It can be concluded that the Astra Tech implant system was successfully used by the general dentist both surgically and prosthetically with minimal implant failures and prosthetic complications and that this led to high levels of patient appreciation and overall satisfaction. [source] Marginal Bone Loss at Implants: A Retrospective, Long-Term Follow-Up of Turned Brånemark System® ImplantsCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2009Odont Lic, Solweig Sundén Pikner DDS ABSTRACT Background: Lately, presence of progressive bone loss around oral implants has been discussed. Purpose: The aim of this study was to report in a large patient group with different prosthetic restorations marginal bone level and its change as measured in radiographs obtained from prosthesis insertion up to a maximum 20 years in service. Further, it also aimed to study the impact of gender, age, jaw, prosthetic restoration, and calendar year of surgery. Materials and Methods: Out of 1,716 patients recorded for clinical examination during 1999, 1,346 patients (78.4%) could be identified. A total of 640 patients (3,462 originally installed Brånemark System® implants, Nobel Biocare, Göteborg, Sweden) with a follow-up of ,5 years were included in the study, while patients with continuous overdentures and augmentation procedures were not. Distance between the fixture/abutment junction (FAJ) and the marginal bone level was recorded. Results: The number of implants with a mean bone level of ,3 mm below FAJ increased from 2.8% at prosthesis insertion to 5.6% at year 1, and 10.8% after 5 years. Corresponding values after 10, 15, and 20 years were 15.2, 17.2, and 23.5%, respectively. Implant-based bone loss was as a mean 0.8 mm (SD 0.8) after 5 years, followed by only minor average changes. Mean bone loss on patient level followed a similar pattern. Disregarding follow-up time, altogether 183 implants (107 patients) showed a bone loss ,3 mm from prosthesis insertion to last examination. Significantly larger bone loss was found the older the patient was at surgery and for lower jaw implants. Conclusions: Marginal bone support at Brånemark implants was with few exceptions stable over years. [source] Clinical and Microbiological Determinants of Ailing Dental ImplantsCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2009Giorgio Tabanella DDS ABSTRACT Background: The failure of the host tissue to establish or maintain osseointegration around dental implants is due to either occlusal or parafunctional forces, premature loading, ill-directed stress, or microbial infection. The long-term failure rate of dental implants is generally 5,10%. Although a variety of etiologies of early peri-implant bone loss (from implant placement to 1-year post-loading) have been proposed, factors associated with late implant failures are less well understood but are probably related to both the peri-implant microbial environment and host factors. Discriminating between causes of implant failure is of importance for instituting a successful implant therapy. Purpose: The objective of this cross-sectional split-mouth study was to identify clinical, radiographic, and bacterial characteristics of peri-implant disease sites. Materials and Methods: Fifteen patients with bilateral implants (Brånemark®, Nobel Biocare AB, Göteborg, Sweden; and 3iÔ implant systems, Implant Innovations Inc., Palm Beach Gardens, FL, USA) participated in the study. Sites with peri-implantitis (radiographic bone loss beyond the third implant thread) and peri-implant healthy tissues (radiographic bone level above the first implant thread) were identified in periapical radiographs using a long-cone paralleling projection technique. Microbiological identification was carried out using established anaerobic culture techniques. A descriptive statistics based on means and standard deviations was reported. Results: Peri-implant bone loss was associated with the absence of radiographic crestal lamina dura, peri-implant pocket depth, pain on chewing, and the submucosal presence of the putative periodontopathogens Tannerella forsythia, Campylobacter species, and Peptostreptococcus micros. Pain was associated with P. micros, Fusobacterium species, and Eubacterium species. Discussion and Conclusion: The absence of radiographic crestal lamina dura and the presence of suspected major periodontal pathogens seem to be associated to peri-implantitis. [source] Implant Stability during Initiation and Resolution of Experimental Periimplantitis: An Experimental Study in the DogCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2005Lars Sennerby DDS ABSTRACT Background: Histologic studies have demonstrated the possibility to reestablish direct bone-implant contacts after ligature-induced periimplantitis. The influence of the reosseointegration on the stability of implants is not known. Purpose: The aim of the present investigation was to study bone tissue and associated implant stability alterations that occurred during induction and resolution of periimplantitis using resonance frequency analysis (RFA), radiography, and histology. Materials and Methods: Three implants with smooth (turned) or roughened (SLA®) surfaces were placed in each side of the edentulous mandible of four dogs. Experimental periimplantitis was induced for 3 months. Five weeks later, the animals were treated with antibiotics and surgical therapy and were followed for another 6 months. Periapical radiographs and RFA were used to evaluate marginal bone levels and implant stability throughout the study period. After termination, the tissue-implant interface was evaluated by light microscopy in ground sections. Results: There was a linear relationship between radiographic and RFA findings because continuous loss of marginal bone and a decrease in implant stability were observed for both implant surfaces during the periimplantitis period. Antibiotic treatment and surgical therapy resulted in some reosseointegration, which was more marked for the SLA surface. The resonance frequency values corresponded well to the histometric measurements because reosseointegration resulted in an increase in implant stability. Conclusions: The findings from the present study indicate a linear relationship between marginal bone level and resonance frequency value. It is suggested that the RFA technique is sensitive and may be used to detect even a minor change in the level of bone-implant contact. [source] A Three-Year Follow-Up Report of a Comparative Study of ITI Dental Implants® and Brånemark System® Implants in the Treatment of the Partially Edentulous MaxillaCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2004Per Åstrand DDS ABSTRACT Background: Many longitudinal studies of different implant systems have been published but few controlled randomized investigations have been reported. A 1-year report of a comparative study of ITI Dental Implant System® implants (Straumann AG, Waldenburg, Switzerland) and Brånemark System® implants (Nobel Biocare AB, Gothenburg, Sweden) has been published by the present authors. This paper is a 3-year follow-up of that randomized study. Purpose: The aim of the study was to compare the outcome of fixed partial prostheses supported by ITI or Branemark implants. The outcome was evaluated primarily in terms of survival rates and changes in marginal bone level. Material and Methods: The study group comprised 28 patients with anterior residual dentition in the maxilla. The patients were provided with two to four implants on each side of the dentition and were randomly allocated to Brånemark implants or ITI implants; 77 ITI implants and 73 Brånemark implants were inserted. After 6 months abutment connections were made to both ITI and Brånemark implants. All patients were provided with fked partial prostheses of gold-ceramic. The patients were followed up annually with clinical and radiographic examinations for 3 years. Results: Two Brånemark implants and two ITI implants were lost. The Brånemark implants were lost before loading whereas the ITI implants were lost because of periimplantitis. The survival rate for both groups was 97.3%. The mean marginal bone level of the Brånemark implants was situated 1.8 mm from the reference point at both the baseline and the 3-year examinations. The corresponding values for the ITI implants were 1.4 mm at baseline and 1.3 mm after 3 years. There was no significant difference between the implant systems with regard to bone level or bone level change. A steady state of the marginal bone level was calculated to have been reached after 3 years for 95.5% of the Brånemark implants and 87.1% of the ITI implants. Periimplantitis (infection including pus and bone loss) was observed with seven ITI implants but with none of the Brånemark implants. This difference was statistically significant. Conclusions: No statistically significant differences were found between the implants studied, except for the frequency of periimplantitis, which was higher for the ITI implants. The survival rates were high, and the marginal bone loss was small for both systems. [source] Stability Measurements of Osseointegrated Implants Using Osstell in Partially Edentulous Jaws after 1 Year of Loading: A Pilot StudyCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2002Piero Balleri MD ABSTRACT Background: The introduction of resonance frequency analysis (RFA) as a commercially available technique has made it possible to measure implant stability in implant stability quotient (ISQ) units at any time during the course of implant treatment and loading. However, no information on normal ISQ levels can be found in the literature. Purpose: The aim of this pilot study was to measure the stability of clinically successful implants in partially edentulous patients after 1 year of loading and to study the influence of jaw, anterior/posterior position, implant length, and marginal bone level on implant stability. Materials and Methods: Fourteen partially edentulous patients previously treated with 45 implants were subjected to clinical and radiographie evaluations and RFA measurements using Osstell (Integration Diagnostics, Sävedalen, Sweden) after 1 year of loading. Results: All 45 implants were stable, and implant stability levels were in the range of 57 to 82 ISQ units with a mean of 69 ± 6.5 ISQ after 1 year of loading. Mandibular implants were more stable than were maxillary ones. There were no differences between anterior and posterior implants. No correlation could be found between implant length and stability. Only minor marginal bone resorption was observed. Conclusions: The results from this limited material showed that successfully integrated implants have ISQ levels from 57 to 82 ISQ with a mean of 69 ISQ after 1 year of loading. Mandibular implants are more stable than are maxillary ones. High implant stability can be achieved with short implants and placement in posterior regions. [source] Early Loading of Four or Five Astra Tech Fixtures with a Fixed Cross-Arch Restoration in the MandibleCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2002Bruno Collaert DDS ABSTRACT Background: A change in implant placement has emerged recently from two-stage to one-stage surgery and to earlier and even immediate loading of the fixtures. Purpose: The aim of this study was to verify whether four or five fixtures installed in the edentulous mandible were suitable for early loading with a cross-arch fixed restoration. Materials and Methods: In 25 consecutively treated patients (28,88 yr), four or five Astra Tech fixtures (Mölndal, Sweden) were installed in edentulous mandibles. During the same surgical procedure, the abutments were connected. An impression was taken immediately after surgery. All patients received a fixed prosthetic rehabilitation of 10 to 12 teeth made of a cast metal framework and acrylic teeth/gingiva within a month. The fixtures were followed up clinically and radiographically for 7 to 24 months. Bone level was measured from the most coronal point of the vertical part of the fixture to the most apical bone level mesially or distally. Results: No fixtures were lost during follow-up. No postoperative complications occurred. Radiographic analysis showed a mean bone level of 0.6 mm after 7 to 12 months. Fixtures followed up from 13 to 18 and 19 to 24 months showed a mean bone level of 0.7 mm. Around two fixtures, the bone level was found at the first implant thread. All other fixtures showed the bone level somewhere along the vertical unthreaded part of the fixture. Conclusions: Early loading within 1 month of four or five Astra Tech fixtures in the edentulous mandible is a predictable procedure for a follow-up period of 6 to 24 months. [source] Marginal Bone Level around Implants Assessed in Digital and Film Radiographs: In Vivo Study in the DogCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2000Eva Borg DDS ABSTRACT Background: One of the objectives of postoperative radiographic examinations of implants is to evaluate the marginal bone height and its changes over time. Purpose: The purpose of this study was to assess the influence of digital image processing on measurements of the marginal bone level around implants. Material and Methods: Implants in beagle dogs, used to study the development of peri-implantitis and subsequent healing following treatment, were monitored with conventional radiography and a digital image plate system. Five observers measured the distance between a reference point and the bone level. Measurements in conventional radiographs were made with the use of an x-ray viewer (2X) and a magnifying lens (7X). For the digital images, the system's built-in measuring function was used together with five image processing techniques: edge enhancement (matrixes set on 5 and 25), inverted grey scale, single color highlight, and color intensity mapping together with the brightness and contrast control. From the time of maximum breakdown and the end of the experiment, histologic values were available. Results: Differences between techniques and observers increased toward the end of the healing period. Measurements made at maximum breakdown did not differ significantly from the histologic value. Measurements made after healing all methods, except that using edge enhancement and a 25 × 25 kernel, differed significantly from the histologic value by underestimating the bone level. Conclusions: Measurements of bone level around implants from digital radiographs are as accurate and precise as those from film images. In particular cases, the use of specific image processing algorithms may improve both accuracy and precision. After healing, the histologic specimens showed an incomplete bone fill in the crater with a remaining thin layer of connective tissue in contact with the fixture, and in such situations, the morphology of the bone will give a more complicated diagnostic task. [source] Transmucosal healing around peri-implant defects: crestal and subcrestal implant placement in dogsCLINICAL ORAL IMPLANTS RESEARCH, Issue 8 2010Binh L. T. Tran Abstract Objective: This study was designed to evaluate the transmucosal healing response of implants placed with the junction of the smooth surfaces, either crestal or subcrestal, into simulated extraction defects after healing periods of 1 and 3 months. Materials and methods: A total of 23 Straumann SP ,3.3 mm NN, SLA® 10 mm implants were placed in the mandibular premolar regions of three greyhound dogs 3 months after the teeth were removed. Five control implants were placed at the crestal bone level, and test implants with surgically created peri-implant defects of 1.25 mm wide × 5 mm depth were placed either at the crestal (nine implants) or at the 2 mm subcrestal (nine implants) bone level. Implants on the right side were placed 1 month before the dogs were sacrificed, and implants on the left side were placed 3 months before sacrifice. All dogs had daily plaque control following surgery and were sacrificed 3 months after implant placement for histological and histometric analyses. Results: Mesial,distal ground sections of the control and test implant specimens showed a greater %BIC in the coronal defect region after 3 months of healing. This healing response was incomplete for the test implants compared with the control implants after a 1-month healing period. The histometric measurements for test implants placed at the crestal bone level or 2 mm subcrestal with surgically created peri-implant defects were more coronal or closer to the implant margin compared with the control implants. Additionally, the degree of osseointegration between the newly formed bone and the implant surface was similar between the test implants. Conclusion: Peri-implant defects of 1.25 mm width healed with spontaneous bone regeneration around implants placed transmucosally at crestal or 2 mm subcrestal with a high degree of osseointegration after a 3-month healing period. To cite this article: Tran BLT, Chen ST, Caiafa A, Davies HMS, Darby IB. Transmucosal healing around peri-implant defects: crestal and subcrestal implant placement in dogs. Clin. Oral Impl. Res. 21, 2010; 794,803. doi: 10.1111/j.1600-0501.2010.01911.x [source] Long-term, retrospective evaluation (implant and patient-centred outcome) of the two-implant-supported overdenture in the mandible.CLINICAL ORAL IMPLANTS RESEARCH, Issue 5 2010Part 2: marginal bone loss Abstract Objective: In part 2 of this long-term, retrospective study on the two-implant-supported overdenture in the mandible, the annual marginal bone loss was evaluated in detail and parameters, with a significant effect on the annual bone loss, were verified. Material and methods: For all 495 patients with an overdenture in the mandible at least 5 years in function, data up to their last follow-up visit had been collected, including long-cone radiographs (taken at the abutment connection and after years 1, 3, 5, 8, 12 and 16 of loading) and probing data at their last evaluation. General information (medical history, implant data, report on surgery) was retrieved from the patient's file. Two hundred and forty-eight patients had been clinically examined recently. For the others, information on bone level and probing depths were retrieved from the patient's files, as all patients had been enrolled in our annual follow-up schedule. Results: The mean annual bone loss on a site level (without considering the first year of bone remodelling) after 3 years of loading was 0.08 mm/year (SD=0.22, n=1105), after 5 years of loading 0.07 mm/year (SD=0.14, n=892), after 8 years of loading 0.06 mm/year (SD=0.12, n=598), after 12 years 0.04 mm/year (SD=0.07, n=370) and 0.05 mm/year (SD=0.05, n=154) after 16 years of loading. Ongoing bone loss was seen in a number of implants (n=26) with the annual bone loss exceeding 0.2 mm. Some factors clearly showed a significant impact on bone loss: smoking (,10 cigarettes/day), GBR, the presence of dehiscence and bone quantity(the latter only during the first year). The probing data showed a favourable condition, with <1.2% of the approximal pockets being ,6 mm, and 4.1%=5 mm. Conclusions: The mean annual bone loss over the study period was <0.1 mm/year after the first year of loading. However, a small number (2.5%) of the implants showed continuing bone loss. To cite this article: Vercruyssen M, Quirynen M. Long-term, retrospective evaluation (implant and patient-centred outcome) of the two-implants-supported overdenture in the mandible. Part 2: marginal bone loss. Clin. Oral Impl. Res. 21, 2010; 466,472. doi: 10.1111/j.1600-0501.2009.01902.x [source] Effect of conical configuration of fixture on the maintenance of marginal bone level: preliminary results at 1 year of functionCLINICAL ORAL IMPLANTS RESEARCH, Issue 4 2010Jung-Joo Kim Abstract Objectives: To evaluate and to compare the effect of the conical neck design on marginal bone loss around the fixtures, when both implants were provided with micro-threads to the top of the fixture. Materials and methods: Two types of implant, one with a straight shape (S) and the other with a conical neck design (C) provided with a retentive element to the top of the fixture, were placed adjacent to each other in the partially edentulous areas of 12 patients. Bone loss around each implant was analyzed after 1 year of functional loading. The bone losses after loading were compared using Wilcoxon's signed-rank test. Results: The mean marginal bone losses (S, 0.05±0.09 mm; C, 0.07±0.14 mm) were not statistically significant between the two groups (P=0.578). Conclusions: There was no significant difference between conical and straight neck implants in terms of marginal bone loss after 1 year of loading. To cite this article: Kim J-J, Lee D-W, Kim C-K, Park K-H, Moon I-S. Effect of conical configuration of fixture on the maintenance of marginal bone level: preliminary results at 1 year of function. Clin. Oral Impl. Res. 21, 2010; 439,444 doi: 10.1111/j.1600-0501.2009.01871.x [source] A randomized-controlled clinical trial evaluating clinical and radiological outcomes after 3 and 5 years of dental implants placed in bone regenerated by means of GBR techniques with or without the addition of BMP-2CLINICAL ORAL IMPLANTS RESEARCH, Issue 7 2009Ronald E. Jung Abstract Objective: The aim of this randomized-controlled clinical trial was to evaluate the long-term outcome of implants placed in bone augmented with a xenogenic bone substitute material and a collagen membrane with or without the addition of recombinant human bone morphogenetic protein-2 (rhBMP-2). Material and methods: Eleven patients received a total of 34 implants placed into sites exhibiting lateral bone defects. In a split mouth design, the defects were randomly treated with the graft material and the collagen membrane either with (test) or without (control) rhBMP-2. The patients were examined 3 and 5 years after insertion of the prosthetic restoration. Student's paired t -test was performed to detect differences between the two groups. Results: The survival rate at 3 and 5 years was 100% for both groups. The peri-implant soft tissues were stable and healthy without any difference between the two groups. The prosthetic reevaluation demonstrated four loose prosthetic screws during the first 3 years and seven ceramic chippings after 3 and 5 years. The mean distance between the first bone to implant contact to implant abutment junction at 3 years was 1.37 mm (test), 1.22 mm (control), and 1.38 mm (test), and 1.23 mm (control) at 5 years. The difference of <0.2 mm between test and control implants was not statistically significant. The mean change of the marginal bone level between baseline and 5 years ranged from ,0.07 mm (mesial, test), ,0.11 mm (distal, test), ,0.03 mm (mesial, control), to +0.13 mm (distal, control). No statistically significant differences were observed between test and control sites. Conclusion: Implants placed in bone augmented with and without rhBMP-2 revealed excellent clinical and radiological outcomes after 3 and 5 years. [source] Radiographic evaluation of marginal bone levels adjacent to parallel-screw cylinder machined-neck implants and rough-surfaced microthreaded implants using digitized panoramic radiographsCLINICAL ORAL IMPLANTS RESEARCH, Issue 6 2009Hans-Joachim Nickenig Abstract Objective: The purpose of this split-mouth study was to compare macro- and microstructure implant surfaces at the marginal bone level during a stress-free healing period and under functional loading. Material and methods: From January to February 2006, 133 implants (70 rough-surfaced microthreaded implants and 63 machined-neck implants) were inserted in the mandible of 34 patients with Kennedy Class I residual dentitions and followed until February 2008. The marginal bone level was radiographically determined, using digitized panoramic radiographs, at four time points: at implant placement (baseline level), after the healing period, after 6 months of functional loading, and at the end of follow-up. Results: The median follow-up time was 1.9 (range: 1.9,2.1) years. The machined-neck group had a mean crestal bone loss of 0.5 mm (range: 0,2.3) after the healing period, 0.8 mm after 6 months (range: 0,2.4), and 1.1 mm (range: 0,3) at the end of follow-up. The rough-surfaced microthreaded implant group had a mean bone loss of 0.1 mm (range: ,0.4,2) after the healing period, 0.4 mm (range: 0,2.1) after 6 months, and 0.5 mm (range: 0,2.1) at the end of follow-up. The two implant types showed significant differences in marginal bone levels (healing period: P=0.01; end of follow-up: P<0.01). Conclusions: Radiographic evaluation of marginal bone levels adjacent to machined-neck or rough-surfaced microthreaded implants showed that implants with the microthreaded design caused minimal changes in crestal bone levels during healing (stress-free) and under functional loading. [source] Placement of Brånemark implants in the maxillary tuber region: anatomical considerations, surgical technique and long-term resultsCLINICAL ORAL IMPLANTS RESEARCH, Issue 1 2009Arne Ridell Abstract Background: Fixture placement in the tuber area is one way to overcome the problem of insufficient bone volume for routine implant surgery in the posterior maxilla due to severe resorption of jawbone and an extensive enlargement of the maxillary sinus. However, little is known about the long-term results. Purpose: The aim of this study was to retrospectively evaluate the survival rate and marginal bone conditions at fixtures placed in the tuber region of the maxilla. Material and methods: Twenty-one patients previously treated with at least one implant in the tuber region of the maxilla were included in this retrospective analysis. A total of 23 standard Brånemark System fixtures with a turned surface had been surgically placed in the tuber regions and 71 additional implants in adjacent areas to support fixed dental bridges. All implants were allowed to heal for 6,8 months before abutment connection and following prosthetic treatment. The patients were radiographed after 1,12 years for evaluation of marginal bone levels. In addition, the relation between the apex of the fixture in the tuberosity area and the posterior border of the maxilla was measured. Results: Twenty of the 21 patients representing 22 tuber and 64 additional implants were radiographically evaluated. No implants in the tuber areas were lost during the follow-up whereas two fixtures in the anterior region had to be removed, one before loading and the other after 4 years of loading not interfering with the prosthesis stability. The mean marginal bone level at tuber implants was situated on average 1.6 mm (SD 1.1, n=22) from the abutment-fixture junction, whilst the other implants showed an average bone level of 1.9 mm (SD 0.8, n=64). The results were similar when comparing partially and totally edentulous patients. Conclusion: The present retrospective study shows good clinical outcome with standard Brånemark fixtures placed in the tuber region of the posterior maxilla using a two-stage procedure. In appropriate cases where bone of adequate volume and density is available, our data indicate that the technique can be used as an alternative to more extensive surgery and especially to the sinus lift procedure. However, prospective comparative studies are needed in order to evaluate the efficacy of the described technique for this purpose. [source] Implants in fresh extraction sockets: a prospective 5-year follow-up clinical studyCLINICAL ORAL IMPLANTS RESEARCH, Issue 12 2008Daniele Botticelli Abstract Objective: The aim of this prospective study was to evaluate the 5-year clinical outcome of the ,immediate implants.' Material and methods: One week after the cementation of the prosthesis, a clinical baseline examination was carried out. Clinical measurements were performed of the following: plaque, mucositis, probing pocket depth, and soft tissue position. The height of the keratinized mucosa was measured at the buccal/lingual aspects. Standardized intra-oral radiographs were taken. The marginal level of bone to implant contact [radiographic (Rx) bone level] was measured, and Rx bone level change over time was evaluated. The clinical/radiographic measurements were repeated on a yearly basis. The subjects were enrolled in a carefully supervised oral hygiene program. Results and conclusion: It was demonstrated that ,immediate implants' that were loaded after 5,7 months had a high success rate. During the 5-year interval, no implant was lost, and the mean Rx bone level at the implants was maintained or even improved. The plaque and mucositis scores were low (<20%) at baseline and at all re-examinations. Implant sites located adjacent to the teeth showed bone gain during the initial period while sites that were facing edentulous zones lost some bone. [source] | |||||||||||||