Showing papers in "Clinical Oral Implants Research in 2011"
TL;DR: While healing showed similar characteristics with bone resorptive and appositional events for both SLActive and SLA surfaces between 7 and 42 days, the degree of osseointegration after 2 and 4 weeks was superior for the SLActive compared with the SLA surface.
Abstract: To evaluate the rate and degree of osseointegration at chemically modified moderately rough, hydrophilic (SLActive) and moderately rough, hydrophobic (SLA) implant surfaces during early phases of healing in a human model.
362 citations
TL;DR: In this article, the authors assess the benefit of socket preservation therapies in patients with a tooth extraction in the anterior or premolar region as compared with no additional treatment with respect to bone level.
Abstract: Objective: To assess, based on the existing literature, the benefit of socket preservation therapies in patients with a tooth extraction in the anterior or premolar region as compared with no additional treatment with respect to bone level.
Material and methods: MEDLINE-PubMed and the Cochrane Central Register of controlled trials (CENTRAL) were searched till June 2010 for appropriate studies, which reported data concerning the dimensional changes in alveolar height and width after tooth extraction with or without additional treatment like bonefillers, collagen, growth factors or membranes.
Results: Independent screening of the titles and abstracts of 1918 MEDLINE-PubMed and 163 Cochrane papers resulted in nine publications that met the eligibility criteria. In natural healing after extraction, a reduction in width ranging between 2.6 and 4.6 mm and in height between 0.4 and 3.9 mm was observed. With respect to socket preservation, the freeze-dried bone allograft group performed best with a gain in height, however, concurrent with a loss in width of 1.2 mm.
Conclusion: Data concerning socket preservation therapies in humans are scarce, which does not allow any firm conclusions. Socket preservation may aid in reducing the bone dimensional changes following tooth extraction. However, they do not prevent bone resorption because, depending on the technique, on the basis of the included papers one may still expect a loss in width and in height.
264 citations
TL;DR: Smoking and compliance are important risk factors for periimplant inflammations in partially edentulous patients in a private dental practice.
Abstract: Objectives: Evaluation of the prevalence rates of periimplant mucositis and periimplantitis in partially edentulous patients in a private dental practice.
Material and methods: The data of 89 patients were collected (52 female, 37 male, age at time of implant placement: 51.8±10.3 years). All patients had been treated with dental implants of the same type and fixed superstructures between January 1999 and June 2006 (observational period: 68.2±24.8 months).
Results: The patient-related prevalence rate of periimplant mucositis (probing depth ≥4 mm and bleeding on probing [BOP]) was over all 44.9%. The respective rates in non-smokers without periodontal history were 30.4% and in smokers with periodontal history 80%. The multiple logistic regression analysis identified a significant association of mucositis with the independent variable “smoker” (odds ratio [OR] 3.77; P=0.023). The patient-related prevalence rate of periimplantitis (probing depth ≥5 mm, BOP/pus, radiographic bone loss) was 11.2% (smokers with periodontal history: 53.3%, non-smokers: 2.8%). No periimplant disease was diagnosed in non-smoking patients without periodontal history and with a good compliance after treatment. Statistical analysis identified a significant association of periimplantitis with “smoker” (OR: 31.58; P<0.001) and “compliance” (OR: 0.09; P=0.011). Periodontal history in general showed no significant association with periimplantitis.
Conclusions: Smoking and compliance are important risk factors for periimplant inflammations in partially edentulous patients.
To cite this article:
Rinke S, Ohl S, Ziebolz D, Lange K, Eickholz P. Prevalence of periimplant disease in partially edentulous patients: a practice-based cross-sectional study.
Clin. Oral Impl. Res. 22, 2011; 826–833
doi: 10.1111/j.1600-0501.2010.02061.x
261 citations
TL;DR: Most tooth sites in the anterior maxilla have a thin facial bone wall, which must be considered before tooth removal and the planning of rehabilitation in the posterior segment of the dentition in the maxilla.
Abstract: Objective: To determine the thickness of the facial bone wall in the anterior dentition of the maxilla and at different locations apical to the cemento-enamel junction (CEJ).
Material and methods: Two-hundred and fifty subjects, aged between 17 and 66 years, with all maxillary front teeth present were included. Written informed consents were obtained. Cone-beam computed tomography scans were performed with the iCAT unit. This examination included all tooth and edentulous sites in the dentition. The images were acquired by means of the iCAT software and processed by a computer. Measurements of the (i) distance between the CEJ and the facial bone crest and (ii) the thickness of the facial bone wall were performed. The bone wall dimensions were assessed at three different positions in relation to the facial bone crest, i.e., at distances of 1, 3, and 5 mm apical to the crest.
Results: The measurements demonstrated that (i) the distance between the CEJ and the facial bone crest varied between 1.6 and 3 mm and (ii) the facial bone wall in most locations in all tooth sites examined was ≤1 mm thick and that close to 50% of sites had a bone wall thickness that was ≤0.5 mm.
Conclusion: Most tooth sites in the anterior maxilla have a thin facial bone wall. Such a thin bone wall may undergo marked dimensional diminution following tooth extraction. This fact must be considered before tooth removal and the planning of rehabilitation in the anterior segment of the dentition in the maxilla.
To cite this article:
Januario AL, Duarte WR, Barriviera M, Mesti JC, Araujo MG, Lindhe J. Dimension of the facial bone wall in the anterior maxilla: a cone-beam computed tomography study.
Clin. Oral Impl. Res. 22, 2011; 1168–1171
doi: 10.1111/j.1600-0501.2010.02086.x.
10.1111/j.1600-0501.2010.02086.x
238 citations
TL;DR: It was demonstrated that the placement of Bio-Oss Collagen in the void between the implant and the buccal-approximal bone walls of fresh extraction sockets modified the process of hard tissue healing, provided additional amounts ofhard tissue at the entrance of the previous socket and improved the level of marginal bone-to-implant contact.
Abstract: Background: Following tooth extraction and immediate implant installation, the edentulous site of the alveolar process undergoes substantial bone modeling and the ridge dimensions are reduced.
Objective: The objective of the present experiment was to determine whether the process of bone modeling following tooth extraction and immediate implant placement was influenced by the placement of a xenogenic graft in the void that occurred between the implant and the walls of the fresh extraction socket.
Material and methods: Five beagle dogs about 1 year old were used. The 4th premolar in both quadrants of the mandible (4P4) were selected and used as experimental sites. The premolars were hemi-sected and the distal roots removed and, subsequently, implants were inserted in the distal sockets. In one side of the jaw, the marginal buccal-approximal void that consistently occurred between the implant and the socket walls was grafted with Bio-Oss® Collagen while no grafting was performed in the contra-lateral sites. After 6 months of healing, biopsies from each experimental site were obtained and prepared for histological analyses.
Results: The outline of the marginal hard tissue of the control sites was markedly different from that of the grafted sites. Thus, while the buccal bone crest in the grafted sites was comparatively thick and located at or close to the SLA border, the corresponding crest at the control sites was thinner and located a varying distance below SLA border.
Conclusions: It was demonstrated that the placement of Bio-Oss® Collagen in the void between the implant and the buccal-approximal bone walls of fresh extraction sockets modified the process of hard tissue healing, provided additional amounts of hard tissue at the entrance of the previous socket and improved the level of marginal bone-to-implant contact.
To cite this article:
Araujo MG, Linder E, Lindhe J. Bio-Oss® Collagen in the buccal gap at immediate implants: a 6-month study in the dog.
Clin. Oral Impl. Res. 22, 2011; 1–8.
doi: 10.1111/j.1600-0501.2010.01920.x
227 citations
TL;DR: The thickness of the peri-implant soft tissue did not appear to be a crucial factor in the abutment impact on the soft tissue color, no matter which type of restorative material is selected.
Abstract: Purpose: The aim of this clinical research on implant-supported restorations is to analyze, through spectrophotometric digital technology, the influence of the abutment material on the color of the peri-implant soft tissue. Material and methods: Twenty patients received an endosseous dental implant in the anterior maxilla. At the time of each definitive prosthesis delivery, an all-ceramic crown has been tried on gold, titanium and zirconia abutment. After the insertion of each single abutment, the peri-implant soft tissue color has been measured through a spectrophotometer. Also, the thickness of the facial periimplant soft tissue was measured at the level of the implant neck through a caliper. A specific software has been utilized to identify a specific tissue area and to collect the data before the statistical analysis in Lab n color space. The normality of the quantitative variables was verified by means of the Shapiro‐ Wilk test. Simple linear correlation between quantitative variables was evaluated by using Pearson’s coefficient. The results on the performance of the abutment materials with regard to the color measurements and the overall measurement DE were described by computing the least-square means. The significance of differences among types of abutment was verified by means of the Scheffe test for multiple comparisons. Results: For all the abutments used, the color of the peri-implant soft tissue appeared to be significantly different from the one of the contra-lateral tooth (DE48.5). Significantly higher (Po0.05) difference were present with the use of titanium abutments (11 " 0.4) when compared with the results of gold (8.9 " 0.4) and zirconia (8.5 " 0.4) abutments. No correlation has been demonstrated between soft tissue thickness and degree of color difference (P40.25). Conclusions: Within the limitation of the present study, the peri-implant soft tissue color appears to be different from the soft tissue color around natural teeth, no matter which type of restorative material is selected. When titanium abutment was selected, significantly higher differences were present than those obtained with gold or zirconia abutments. The thickness of the peri-implant soft tissue did not appear to be a crucial factor in the abutment impact on the soft tissue color.
190 citations
TL;DR: It is indicated that titanium can induce hypersensitivity in susceptible patients and could play a critical role in implant failure, and the need for long-term clinical and radiographic follow-up of all implant patients who are sensitive to metals is supported.
Abstract: Purpose: Degradation products of metallic biomaterials including titanium may result in metal hypersensitivity reaction. Hypersensitivity to biomaterials is often described in terms of vague pain, skin rashes, fatigue and malaise and in some cases implant loss. Recently, titanium hypersensitivity has been suggested as one of the factors responsible for implant failure. Although titanium hypersensitivity is a growing concern, epidemiological data on incidence of titanium-related allergic reactions are still lacking.
Materials and methods: A computer search of electronic databases primarily MEDLINE and PUBMED was performed with the following key words: ‘titanium hypersensitivity’, ‘titanium allergy’, ‘titanium release’ without any language restriction. Manual searches of the bibliographies of all the retrieved articles were also performed. In addition, a complementary hand search was also conducted to identify recent articles and case reports.
Results: Most of the literature comprised case reports and prospective in vivo/in vitro trials. One hundred and twenty-seven publications were selected for full text reading. The bulk of the literature originated from the orthopaedic discipline, reporting wear debris following knee/hip arthroplasties. The rest comprised osteosynthesis (plates/screws), oral implant/dental materials, dermatology/cardiac-pacemaker, pathology/cancer, biomaterials and general reports.
Conclusion: This review of the literature indicates that titanium can induce hypersensitivity in susceptible patients and could play a critical role in implant failure. Furthermore, this review supports the need for long-term clinical and radiographic follow-up of all implant patients who are sensitive to metals. At present, we know little about titanium hypersensitivity, but it cannot be excluded as a reason for implant failure.
To cite this article:
Siddiqi A, Payne AGT, De Silva RK, Duncan WJ. Titanium allergy: could it affect dental implant integration?
Clin. Oral Impl. Res. 22, 2011; 673–680
doi: 10.1111/j.1600-0501.2010.02081.x
181 citations
TL;DR: The amount of residual cement after cleaning increased as the restoration margins were located deeper subgingivally, using weighting and calculation of proportion, and there was a significant correlation between evaluation techniques.
Abstract: Objectives The aim of this study was to evaluate the amount of the residual cement excess after cementation and cleaning of implant-supported restorations with various positions of the margins Material and methods Twenty-five casts with embedded implant analogs and flexible soft-tissue imitation were used in the study Individual abutments with different position of the margin - from 1 mm supragingivally to 3 mm below the gingival level - were modelled and divided equally into five groups The same amount of polished metal crowns was luted to prosthetic abutments, excess cement was cleaned and the restorations were removed for evaluation of the undetected cement remnants All quadrants of each specimen were photographed for calculation of the ratio between the cement remnants area and the total specimen area using Adobe Photoshop Afterwards, cement remnants were cleared from each specimen and weighed with analytical balances Results The measurements in all the groups consisted of (1) the relation between the cement remnants area and the total area of the specimen; and (2) cement excess weight in grams after cleaning: group 1 (00111 ± 0021; 00003 ± 00001 g); group 2 (00165 ± 0019; 00008 ± 00003 g); group 3 (00572 ± 0028; 00013 ± 00005 g); group 4 (01158 ± 0054; 00051 ± 00013 g); and group 5 (01171 ± 0059; 00063 ± 00021 g) Results showed significant increase of undetected cement quantity, as the restoration margins were located deeper subgingivally, using weighting (P=0) and calculation of proportion (P=0) There was a significant correlation between evaluation techniques (r=0889; P=0) Conclusions The amount of residual cement after cleaning increased as the restoration margins were located more subgingivally
178 citations
TL;DR: The clinical procedures were effective in augmenting peri-implant tissue volume that remained stable to a high degree within 1 year after crown insertion, and large inter-individual variations regarding the tissue alterations were observed.
Abstract: OBJECTIVES: the aim of the present study was to evaluate the dimensional changes of peri-implant tissues obtained by implant placement, bone and soft tissue augmentation, prosthetic reconstruction and 1 year of function using a new, non-invasive method for volumetric measurements.
MATERIALS AND METHODS: in 16 patients, the missing central or lateral maxillary incisor was reconstructed with an implant-supported single crown. Impressions were taken before (t1), after implant placement with guided bone regeneration using DBBM and a PTFE membrane (t2), after soft tissue augmentation (t3), immediately after crown placement (t4) and 1 year later (t5). The cast models were optically scanned and digitally superimposed allowing qualitative and quantitative analysis of alterations of the labial peri-implant tissue contour. In addition, the crown length and papilla height were measured at crown placement (t4) and after 1 year (t5).
RESULTS: fifteen patients were available for recall after 1 year. During therapy, a mean gain in distance in the labial direction of 1.27 ± 0.67 mm was observed after the surgical procedures. One year after crown insertion, a mean loss of 0.04 ± 0.31 mm in the labial direction was recorded. During the same period, the crown length increased by a mean of 0.22 ± 0.57 mm and the papilla height by 0.07 ± 0.61 mm. The degree and pattern of tissue change following crown insertion were highly variable between individuals, irrespective of the amount and quality of previously augmented tissues.
CONCLUSIONS: the clinical procedures were effective in augmenting peri-implant tissue volume that remained stable to a high degree within 1 year after crown insertion. Large inter-individual variations regarding the tissue alterations were observed
161 citations
TL;DR: Density profiles of MSCT showed stable HU values, whereas in CBCT imaging the intensity values were variable over the profile, indicating that the use of intensity values inCBCT images is not reliable.
Abstract: Objectives: The aim of this study was to evaluate the variability of intensity values in cone beam computed tomography (CBCT) imaging compared with multislice computed tomography Hounsfield units (MSCT HU) in order to assess the reliability of density assessments using CBCT images.
Material and methods: A quality control phantom was scanned with an MSCT scanner and five CBCT scanners. In one CBCT scanner, the phantom was scanned repeatedly in the same and in different positions. Images were analyzed using registration to a mathematical model. MSCT images were used as a reference.
Results: Density profiles of MSCT showed stable HU values, whereas in CBCT imaging the intensity values were variable over the profile. Repositioning of the phantom resulted in large fluctuations in intensity values.
Conclusions: The use of intensity values in CBCT images is not reliable, because the values are influenced by device, imaging parameters and positioning.
To cite this article:
Nackaerts O, Maes F, Yan H, Couto Souza P, Pauwels R, Jacobs R. Analysis of intensity variability in multislice and cone beam computed tomography.
Clin. Oral Impl. Res. 22, 2011; 873–879.
doi: 10.1111/j.1600-0501.2010.02076.x
157 citations
TL;DR: Gender seems to be the most important parameter influencing mucosal thickness in asymptomatic patients, and there is great interindividual variability in the thickness of the Schneiderian membrane.
Abstract: To determine the dimensions of the Schneiderian membrane using limited cone beam computed tomography (CBCT) in individuals referred for dental implant surgery, and to determine factors influencing the mucosal thickness.
TL;DR: Compared with SLA, SLActive exerts a pro-osteogenic and pro-angiogenic influence on gene expression at day 7 following implant insertion, which may be responsible for the superior osseointegrative properties of this surface.
Abstract: OBJECTIVES: To compare the gene expression profile of osseointegration associated with a moderately rough and a chemically modified hydrophilic moderately rough surface in a human model.
MATERIAL AND METHODS: Eighteen solid screw-type cylindrical titanium implants, 4 mm long and 2.8 mm wide, with either a moderately rough (SLA) or a chemically modified moderately rough (SLActive) surface were surgically inserted in the retromolar area of nine human volunteers. The devices were removed using a trephine following 4, 7 and 14 days of healing. The tissue surrounding the implant was harvested, total RNA was extracted and microarray analysis was carried out to identify the differences in the transcriptome between the SLA and SLActive surfaces at days 4, 7 and 14.
RESULTS: There were no functionally relevant gene ontology categories that were over-represented in the list of genes that were differentially expressed at day 4. However, by day 7, osteogenesis- and angiogenesis-associated gene expression were up-regulated on the SLActive surface. Osteogenesis and angiogenesis appeared to be regulated by BMP and VEGF signalling, respectively. By day 14, VEGF signalling remains up-regulated on the SLActive surface, while BMP signalling was up-regulated on the SLA surface in what appeared to be a delayed compensatory response. Furthermore, neurogenesis was a prominent biological process within the list of differentially expressed genes, and it was influenced by both surfaces.
CONCLUSIONS: Compared with SLA, SLActive exerts a pro-osteogenic and pro-angiogenic influence on gene expression at day 7 following implant insertion, which may be responsible for the superior osseointegrative properties of this surface.
TL;DR: Non-surgical debridement and oral hygiene were effective in reducing peri-implant mucositis, but did not always result in complete resolution of inflammation.
Abstract: To compare the effectiveness of two anti-infective protocols for the treatment of peri-implant mucositis.
TL;DR: The decrease in BD : ST ratio suggests that bone debris, created during implant installation and adhering to moderately rough surfaces, significantly contributed to the initiation of bone deposition and mediated the connection between the old bone and the new bone on the implant surface.
Abstract: To evaluate morphologically and morphometrically the sequential healing and osseointegration events at moderately rough implant surfaces with and without chemical modification. Particularly the role of bone debris in initiating bone formation was emphasized.
TL;DR: It is expected that the difference in light reflection of soft tissue covering Ti or ZrO(2) abutments is no longer noticeable for the human eye when the mucosa thickness exceeds 2 mm, making hyper-spectral imaging a practical and useful tool for measuring soft tissue health.
Abstract: Objectives: To determine the difference in light reflection of oral mucosa covering titanium (Ti) or zirconia (ZrO2) abutments as it relates to the thickness of the covering mucosa.
Material and methods: Fifteen anterior implants (Astra Osseo speed®) in 11 patients were fitted with a Ti or a ZrO2 abutment (cross-over, within-subject comparison). Hyper-spectral images were taken with a camera fitted on a surgical microscope. High-resolution images with 70 nm interval between 440 and 720 nm were obtained within 30 s (1392 × 1024 pixels). Black- and white-point reference was used for spatial and spectral normalization as well as correction for motion during exposure. Reflection spectra were extracted from the image on a line mid-buccal of the implant, starting 1 mm above the soft tissue continuing up to 3 mm apically.
Results: Median soft tissue height is 2.3 mm (min: 1.2 mm and max: 3.1 mm). The buccal mucosa rapidly increases in the thickness, when moving apically. At 2.2 mm, thickness is 3 mm. No perceivable difference between the Ti and ZrO2 abutment can be observed when the thickness of the mucosa is 2±0.1 mm (95% confidence interval) or more.
Conclusion: It is expected that the difference in light reflection of soft tissue covering Ti or ZrO2 abutments is no longer noticeable for the human eye when the mucosa thickness exceeds 2 mm. Haemoglobin peaks in the reflection spectrum can be observed and make hyper-spectral imaging a practical and useful tool for measuring soft tissue health.
To cite this article:
van Brakel R, Noordmans HJ, Frenken J, de Roode R, de Wit GC, Cune MS. The effect of zirconia and titanium implant abutments on light reflection of the supporting soft tissues.
Clin. Oral Impl. Res. 22, 2011; 1172–1178
doi: 10.1111/j.1600-0501.2010.02082.x
TL;DR: Araujo et al. as mentioned in this paper examined whether grafting of the alveolar socket with the use of chips of autologous bone may allow ridge preservation following tooth extraction.
Abstract: Background: Studies in humans and animals have shown that following tooth removal (loss), the alveolar ridge becomes markedly reduced Attempts made to counteract such ridge diminution by installing implants in the fresh extraction sockets were not successful, while socket grafting with anorganic bovine bone mineral prevented ridge contraction
Aim: To examine whether grafting of the alveolar socket with the use of chips of autologous bone may allow ridge preservation following tooth extraction
Methods: In five beagle dogs, the distal roots of the third and fourth mandibular premolars were removed The sockets in the right or the left jaw quadrant were grafted with either anorganic bovine bone or with chips of autologous bone harvested from the buccal bone plate After 3 months of healing, biopsies of the experimental sites were sampled, prepared for buccal–lingual ground sections and examined with respect to size and composition
Results: It was observed that the majority of the autologous bone chips during healing had been resorbed and that the graft apparently did not interfere with socket healing or processes that resulted in ridge resorption
Conclusion: Autologous bone chips placed in the fresh extraction socket will (i) neither stimulate nor retard new bone formation and (ii) not prevent ridge resorption that occurs during healing following tooth extraction
To cite this article:
Araujo MG, Lindhe J Socket grafting with the use of autologous bone: an experimental study in the dog
Clin Oral Impl Res 22, 2011; 9–13
doi: 101111/j1600-0501201001937x
TL;DR: Vasak et al. as mentioned in this paper evaluated the overall deviation in a clinical treatment setting to provide for quantification of the potential impairment of treatment safety and reliability with computer-assisted, template-guided transgingival implantation.
Abstract: Objectives: This prospective study was intended to evaluate the overall deviation in a clinical treatment setting to provide for quantification of the potential impairment of treatment safety and reliability with computer-assisted, template-guided transgingival implantation.
Material and methods: The patient population enrolled (male/female=10/8) presented with partially dentate and edentulous maxillae and mandibles. Overall, 86 implants were placed by two experienced dental surgeons strictly following the NobelGuide™ protocol for template-guided implantation. All patients had a postoperative computed tomography (CT) with identical settings to the preoperative examination. Using the triple scan technique, pre- and postoperative CT data were merged in the Procera planning software, a newly developed procedure – initially presented in 2007 allowing measurement of the deviations at implant shoulder and apex.
Results: The deviations measured were an average of 0.43 mm (bucco-lingual), 0.46 mm (mesio-distal) and 0.53 mm (depth) at the level of the implant shoulder and slightly higher at the implant apex with an average of 0.7 mm (bucco-lingual), 0.63 mm (mesio-distal) and 0.52 mm (depth). The maximum deviation of 2.02 mm was encountered in the corono-apical direction. Significantly lower deviations were seen for implants in the anterior region vs. the posterior tooth region (P<0.01, 0.31 vs. 0.5 mm), and deviations were also significantly lower in the mandible than in the maxilla (P=0.04, 0.36 vs. 0.45 mm) in the mesio-distal direction. Moreover, a significant correlation between deviation and mucosal thickness was seen and a learning effect was found over the time period of performance of the surgical procedures.
Conclusion: Template-guided implantation will ensure reliable transfer of preoperative computer-assisted planning into surgical practice. With regard to the required verification of treatment reliability of an implantation system with flapless access, all maximum deviations measured in this clinical study were within the safety margins recommended by the planning software.
To cite this article:
Vasak C, Watzak G, Gahleitner A, Strbac G, Schemper M, Zechner W. Computed tomography-based evaluation of template (NobelGuide™)-guided implant positions: a prospective radiological study.
Clin. Oral Impl. Res. 22, 2011; 1157–1163.
doi: 10.1111/j.1600-0501.2010.02070.x
TL;DR: The present study demonstrates decreasing values for the coronal width of the buccal bone wall in patients with missing central incisors and a time span since tooth loss of over 1 year.
Abstract: To analyze the dimensions and anatomic characteristics of the nasopalatine canal and the corresponding buccal bone plate of the alveolar process, using limited cone-beam computed tomography (CBCT) imaging.
TL;DR: No difference in health of the soft tissues adjacent to ZrO(2) and Ti abutment surfaces or in early bacterial colonization could be demonstrated, although somewhat shallower probing depths were observed around ZrRO( 2) abutments after 3 month.
Abstract: Aim: To compare the early bacterial colonization and soft tissue health of mucosa adjacent to zirconia (ZrO2) and titanium (Ti) abutment surfaces in vivo. Materials and methods: Twenty edentulous subjects received two endosseous mandibular implants. The implants were fitted with either a ZrO2 or a Ti abutment (non-submerged implant placement, within-subject comparison, left-right randomization). Sulcular bacterial sampling and the assessment of probing pocket depth, recession and bleeding on probing were performed at 2 weeks and 3 months post-surgery. Wilcoxon matched-pairs, sign-rank tests were applied to test differences in the counts of seven marker bacteria and the clinical parameters that were associated with the ZrO2 and Ti abutments, at the two observation time points. Results: ZrO2 and Ti abutments harboured similar counts of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, Peptostreptococcus micros, Fusobacterium nucleatum and Treponema denticola at 2 weeks and 3 months. Healthy clinical conditions were seen around both ZrO2 and Ti abutments at all times, without significant differences in most clinical parameters of peri-implant soft tissue health. Mean probing depths around Ti abutments were slightly deeper than around ZrO2 abutments after 3 months (2.2 SD 0.8 mm vs. 1.7 SD 0.7 mm, P=0.03). Conclusions: No difference in health of the soft tissues adjacent to ZrO2 and Ti abutment surfaces or in early bacterial colonization could be demonstrated, although somewhat shallower probing depths were observed around ZrO2 abutments after 3 month.
TL;DR: Rickert et al. as mentioned in this paper used mesenchymal stem cells seeded on BioOss (R) particles to induce the formation of a sufficient volume of new bone to enable the reliable placement of implants within a time frame comparable with that of applying either solely autogeneous bone or a mixture of autogenous bone or autogenous stem cells.
Abstract: Aim To assess whether differences occur in bone formation after maxillary sinus floor elevation surgery with bovine bone mineral (BioOss (R)) mixed with autogenous bone or autogenous stem cells. The primary endpoint was the percentage of new bone three months after the elevation procedure. Material and methods In a randomized, controlled split-mouth design, in 12 consecutive patients (age 60.8 +/- 5.9 years, range 48-69 years) needing reconstruction of their atrophic maxilla, a bilateral sinus floor augmentation procedure was performed. Randomly, on one side the augmentation procedure was performed with bovine bone mineral (BioOss (R)) seeded with mononuclear stem cells harvested from the posterior iliac crest (test group) while BioOss (R) mixed with autogenous bone (harvested from the retromolar area) was applied on the contra-lateral side (control group). On 14.8 +/- 0.7 weeks after the sinus floor elevation, biopsies from the reconstructed areas were taken at the spots where subsequently the endosseous implants were placed. The biopsies were histomorphometrically analyzed. Results Significantly more bone formation was observed in the test group (17.7 +/- 7.3%) when compared with the control group (12.0% +/- 6.6; P=0.026). In both the test and control group, all implants could be placed with primary stability. In one patient, not all biopsies contained BioOss (R). This patient was excluded from analysis. Conclusion Mesenchymal stem cells seeded on BioOss (R) particles can induce the formation of a sufficient volume of new bone to enable the reliable placement of implants within a time frame comparable with that of applying either solely autogenous bone or a mixture of autogenous bone and BioOss (R). This technique could be an alternative to using autografts. To cite this article: Rickert D, Sauerbier S, Nagursky H, Menne D, Vissink A, Raghoebar GM. Maxillary sinus floor elevation with bovine bone mineral combined with either autogenous bone or autogenous stem cells: a prospective randomized clinical trial.Clin. Oral Impl. Res. 22, 2011; 251-258.doi: 10.1111/j.1600-0501.2010.01981.x.
TL;DR: Results of this study indicated that a surgical procedure based on pocket elimination and bone re-contouring and plaque control before and following surgery was an effective therapy for treatment of peri-implantitis for the majority of subjects and implants, however, complete disease resolution at the site level seems to depend on the initial bone loss at implants.
Abstract: Aim: The aim of the present study was to evaluate the outcome of a surgical procedure based on pocket elimination and bone re-contouring for the treatment of peri-implantitis.
Material and methods: The 31 subjects involved in this study presented clinical signs of peri-implantitis at one or more dental implants (i.e. ≥6 mm pockets, bleeding on probing and/or suppuration and radiographic evidence of ≥2 mm bone loss). The patients were treated with a surgical procedure based on pocket elimination and bone re-contouring and plaque control before and following the surgery. At the time of surgery, the amount of bone loss at implants was recorded.
Results: Two years following treatment, 15 (48%) subjects had no signs of peri-implant disease; 24 patients (77%) had no implants with a probing pocket depth of ≥6 mm associated with bleeding and/or suppuration following probing. A total of 36 implants (42%) out of the 86 with initial diagnosis of peri-implantitis presented peri-implant disease despite treatment. The proportion of implants that became healthy following treatment was higher for those with minor initial bone loss (2–4 mm bone loss as assessed during surgery) compared with the implants with a bone loss of ≥5 mm (74% vs. 40%). Among the 18 implants with bone loss of ≥7 mm, seven were extracted. Between the 6-month and the 2-year examination, healthy implants following treatment tended to remain stable, while deepening of pockets was observed for those implants with residual pockets.
Conclusion: The results of this study indicated that a surgical procedure based on pocket elimination and bone re-contouring and plaque control before and following surgery was an effective therapy for treatment of peri-implantitis for the majority of subjects and implants. However, complete disease resolution at the site level seems to depend on the initial bone loss at implants. Implants with no signs of peri-implantitis following treatment tended to remain healthy during the 2-year period, while a tendency for disease progression was observed for the implants that still showed signs of peri-implant disease following treatment.
To cite this article:
Serino G, Turri A. Outcome of surgical treatment of peri-implantitis: results from a 2-year prospective clinical study in humans.
Clin. Oral Impl. Res. 22, 2011; 1214–1220.
doi: 10.1111/j.1600-0501.2010.02098.x
TL;DR: A sound knowledge of the maxillary sinus vascular anatomy and its careful analysis by CT scan is essential to prevent complications during surgical interventions involving this region.
Abstract: Objectives: To investigate the prevalence, location, size and course of the anastomosis between the dental branch of the posterior superior alveolar artery (PSAA), known as alveolar antral artery (AAA), and the infraorbital artery (IOA).
Material and methods: The first part of the study was performed on 30 maxillary sinuses deriving from 15 human cadaver heads. In order to visualize such anastomosis, the vascular network afferent to the sinus was injected with liquid latex mixed with green India ink through the external carotid artery. The second part of the study consisted of 100 CT scans from patients scheduled for sinus lift surgery.
Results: An anastomosis between the AAA and the IOA was found by dissection in the context of the sinus anterolateral wall in 100% of cases, while a well-defined bony canal was detected radiographically in 94 out of 200 sinuses (47% of cases).
The mean vertical distance from the lowest point of this bony canal to the alveolar crest was 11.25±2.99 mm (SD) in maxillae examined by CT. The canal diameter was <1 mm in 55.3% of cases, 1–2 mm in 40.4% of cases and 2–3 mm in 4.3% of cases.
In 100% of cases, the AAA was found to be partially intra-osseous, that is between the Schneiderian membrane and the lateral bony wall of the sinus, in the area selected for sinus antrostomy.
Conclusions: A sound knowledge of the maxillary sinus vascular anatomy and its careful analysis by CT scan is essential to prevent complications during surgical interventions involving this region.
To cite this article:
Rosano G, Taschieri S, Gaudy J-F, Weinstein T, Del Fabbro M. Maxillary sinus vascular anatomy and its relation to sinus lift surgery.
Clin. Oral Impl. Res. 22, 2011; 711–715
doi: 10.1111/j.1600-0501.2010.02045.x
TL;DR: The maxillary sinus membrane elevation and simultaneous placement of implants without the use of bone grafts or bone substitutes result in predictable bone formation with a high implant survival rate of 98.7% during a follow-up period of up to 6 years.
Abstract: Objectives: To investigate the long-term clinical and radiographic results of the maxillary sinus membrane elevation technique where implants were inserted in a void space created by the elevation ...
TL;DR: The results from this study suggested that CT scan is a valuable tool in evaluating presence of sinus pathology, septa, and arteries before maxillary sinus surgery.
Abstract: Objectives: Knowledge and evaluation of the maxillary sinus anatomy before sinus augmentation are essential for avoiding surgical complications. Posterior superior alveolar artery (PSAA) is the branch of maxillary artery that supplies lateral sinus wall and overlying membrane. The aims of this study were to examine the prevalence, diameter, and location of the PSAA and its relationship to the alveolar ridge and to study the prevalence of the sinus pathology and septum using computerized tomography (CT) scans.
Materials and methods: One hundred and twenty-one CT scans (242 sinuses) from patients undergoing sinus augmentation procedure and/or implant therapy were included. Lower border of the artery to the alveolar crest, bone height below the sinus floor to the ridge crest, distance of the artery to the medial sinus wall, diameter of the artery, and position of the artery were measured; presence of septa and pathology were recorded from CT sections.
Results: Prevalence of sinus septa and sinus pathology was 16.1% and 24.8%, respectively. Artery was seen in 64.5% of all sinuses and was mostly intraosseous (68.2%). Mean diameter of PSAA was found 1.3 ± 0.5 mm. No significant correlation between the diameter of the artery and age was observed.
Conclusions: The results from this study suggested that CT scan is a valuable tool in evaluating presence of sinus pathology, septa, and arteries before maxillary sinus surgery. Although variations exist in every patient, the findings from this study suggest limiting the superior border of the lateral window up to 18 mm from the ridge to avoid any potential vascular damage.
To cite this article:
Guncu GN, Yildirim YD, Wang H-L, Tozum TF. Location of posterior superior alveolar artery and evaluation of maxillary sinus anatomy with computerized tomography: a clinical study.
Clin. Oral Impl. Res. 22, 2011; 1164–1167.
doi: 10.1111/j.1600-0501.2010.02071.x
TL;DR: The non-removal of an abutment placed at the time of surgery results in a statistically significant reduction of the horizontal bone remodeling around the immediately restored, subcrestally placed, tapered implant in cases of partial posterior mandibular edentulism.
Abstract: Objectives: The aim of this prospective study was to assess the effects of abutment removal after 6 months on bone healing after the subcrestal placement of immediately restored, tapered implants in cases of partial posterior mandibular edentulism.
Material and methods: Each of the 24 patients with partial posterior mandibular edentulism was consecutively treated with two immediately restored 3.5 mm diameter tapered implants. A total of 48 implants were placed in healed sites and immediately splinted with a temporary restoration, which was placed in such a way as to avoid occlusal contact. Twenty-four weeks after surgery, 12 patients underwent the standard prosthetic protocol: the abutments were removed and impressions were made directly on the implant platform. Twelve patients underwent the “one abutment at one time” protocol: impressions were made of the abutments using snap-on abutment copies. The final restoration was delivered approximately 6 months after implant insertion. Vertical and horizontal bone changes were assessed using periapical radiographs immediately after surgery and at 6-, 12-, 24- and 36-month follow-up examinations.
Results: All implants osseointegrated and were clinically stable at the 6-month follow-up. No statistically significant difference was evidenced between the two groups regarding the measurement of vertical bone healing. A small but significant horizontal bone loss was evidenced in the hard tissue portion over the implant platform in the period of time between the 6-month and 1-year follow-up in the control group.
Conclusions: The non-removal of an abutment placed at the time of surgery results in a statistically significant reduction of the horizontal bone remodeling around the immediately restored, subcrestally placed, tapered implant in cases of partial posterior mandibular edentulism.
To cite this article:
Degidi M, Nardi D, Piattelli A. One abutment at one time: non-removal of an immediate abutment and its effect on bone healing around subcrestal tapered implants.
Clin. Oral Impl. Res. 22, 2011; 1303–1307.
doi: 10.1111/j.1600-0501.2010.02111.x
TL;DR: Dentists must improve communication strategies to provide their patients with comprehensible, legally tenable information on dental implants and bridge information gaps in the future.
Abstract: Objectives: Little is known about the level of information on implant dentistry in the public. A representative opinion poll on dental implants in the Austrian population was published in 2003 (Clinical Oral Implants Research 14:621–642). Seven years later, the poll was rerun to assess the up-to-date information level and evaluate recent progress and trends in patients' mindset on dental implants.
Material and methods: One thousand adults – representative for the Austrian population – were presented with a total of 19 questionnaire items regarding the level and the sources of information about dental implants as well as the subjective and objective need for patient information.
Results: Compared with the survey of 2003, the subjective level of patient information about implant dentistry has significantly increased in the Austrian population. The patients' implant awareness rate was 79%. The objective level of general knowledge about dental implants was still all but satisfactory revealing unrealistic patient expectations. Three-quarters trusted their dentists for information about dental implants, while one-quarter turned to the media. The patients' wish for high-quality implant restorations was significantly higher than in 2003, yet the majority felt that only specialists should perform implant dentistry.
Conclusions: This representative survey reveals that dentists are still the main source of patient information, but throws doubt on the quality of their public relations work. Dentists must improve communication strategies to provide their patients with comprehensible, legally tenable information on dental implants and bridge information gaps in the future.
To cite this article:
Pommer B, Zechner W, Watzak G, Ulm C, Watzek G, Tepper G. Progress and trends in patients' mindset on dental implants. I: level of information, sources of information and need for patient information.
Clin. Oral Impl. Res. 22, 2011; 223–229
doi: 10.1111/j.1600-0501.2010.02035.x
TL;DR: Mandibular single-implant overdentures are a successful treatment option for older edentulous adults with early loading protocol using implants of different diameters and with different attachment systems.
Abstract: Objectives: To determine surgical and prosthodontic outcomes of mandibular single-implant overdentures, opposing complete maxillary dentures, using a wide diameter implant and large ball attachment system compared with different regular diameter implants with standard attachment systems.
Materials and methods: Thirty-six edentulous participants (mean age 68 years, SD 9.2) were randomly assigned into three treatment groups (n=12). A single implant was placed in the mandibular midline of participants to support an overdenture using a 6-week loading protocol. The control group received Southern regular implants and standard ball attachments. One group received Southern 8-mm-wide implants and large ball attachments. Another group received Neoss regular implants and Locator attachments. Parametric and non-parametric tests of a statistical software package (SPSS) were used to determine between groups differences in marginal bone loss, implant stability, implant, and prosthodontic success (P<0.05).
Results: Implant success after 1 year was 75% for Southern regular implant (control) group; and 100% for the Southern wide and Neoss regular implant groups (P=0.038). Mean marginal bone loss at 1 year was 0.19 mm (SD 0.39) without significant differences observed. Implant stability quotient (ISQ) at baseline was significantly lower for the Southern regular (control) group than the other two groups (P=0.001; P=0.009). At 1 year, no significant difference in implant stability was observed (mean ISQ 74.6, SD 6.1). The change in implant stability from baseline to 1 year was significant for the control group (P=0.025). Prosthodontic success was comparable between the groups but the maintenance (41 events overall, mean 1.2) was greater for the Locator and the standard ball attachments.
Conclusions: Mandibular single-implant overdentures are a successful treatment option for older edentulous adults with early loading protocol using implants of different diameters and with different attachment systems.
To cite this article:
Alsabeeha NHM, Payne AGT, De Silva RK, Thomson WM. Mandibular single-implant overdentures: preliminary results of a randomised-control trial on early loading with different implant diameters and attachment systems.
Clin. Oral Impl. Res. 22, 2011; 330–337.
doi: 10.1111/j.1600-0501.2010.02004.x
TL;DR: The temporal transcriptional changes during osseointegration involve the expression of proliferation and immuno-inflammatory response associated genes during the early stages of osseointedegration, which are ultimately replaced by genes associated with the biological processes of skeletogenesis, angiogenesis and neurogenesis.
Abstract: Objective: To determine the temporal gene expression profile associated with the early healing events during osseointegration in a human model. Material and methods: Nine solid screw-type cylindrical titanium implants, 4mm long and 2.8mm wide, with a chemically modified surface (SLActive) were surgically inserted in the retromolar area of nine human volunteers. The devices were removed using a trephine following 4, 7 and 14 days of healing. The tissue surrounding the implant was harvested, total RNA was extracted and microarray analysis was carried out to identify the differences in the transcriptome between days 4, 7 and 14. Results: Gene ontology (GO) analysis of the temporal transcriptional changes was characteristic of a maturing, osteogenic process over the course of the study (4-14 days). At day 4, a gene expression profile associated with proliferation and immuno-inflammatory processes was predominant. However, by day 14, by far the most predominant mechanisms were associated with skeletogenesis, with the GO categories of skeletal system development, bone development and ossification being predominant, with the majority of changes occurring between days 7 and 14. Furthermore, the biological processes of angiogenesis and neurogenesis were also predominant by day 14. In terms of signal transduction, IkB kinase/NF-kB cascade was predominant at day 4, whereas TGF-b/BMP, Wnt and Notch signalling were all associated with the osteogenic process over the duration of the study. Furthermore, Ras and Rho protein signal transduction was regulated throughout the osseointegration process. Conclusion: The temporal transcriptional changes during osseointegration involve the expression of proliferation and immuno-inflammatory response associated genes during the early stages of osseointegration, which are ultimately replaced by genes associated with the biological processes of skeletogenesis, angiogenesis and neurogenesis. The early immuno-inflammatory changes appear to be regulated via the I-kB kinase/NF-kB cascade, whereas the later osteogenesis-related mechanisms are regulated by TGF-b/BMP, Notch and Wnt signaling.
TL;DR: Carmeli et al. as mentioned in this paper assessed the correlation between maxillary sinus inferior mucosal thickening and sinus outflow obstruction and found that a rounded mucosal appearance of any grade is associated with a low risk for sinus obstruction.
Abstract: Objectives: To assess the correlation between maxillary sinus inferior mucosal thickening and sinus outflow obstruction.
Material and methods: The study included 280 computerized tomography (CT) scans (560 maxillary sinuses). CT aimed to assess sinusitis; trauma to the face and intubated patients were excluded. Mucosal thickening was graded as 20 mm (5), and classified by appearance as normal, rounded, circumferential, irregular, or complete. Maxillary sinus outflow was classified as patent or obstructed.
Results: Mucosal thickening was found in 36.1% of the maxillary sinuses, graded as 31.2% (1), 34.2% (2), 12.9% (3), 5.4% (4) and 16.3% (5), and classified as rounded (11.8%), irregular (10.4%), circumferential (8.8%) and complete (5.2%). Sinus outflow was obstructed in 15% of the scans. Mucosal thickening of 10 mm (74.3%) was associated with sinus obstruction (P 5 mm (56.5% for grade 2 up to 82.6% for grades 3–5) and circumferential appearance (21.4% for grade 1 up to 100% for grades 3–5). A low risk for obstruction was found with the rounded appearance (mean 6.1%).
Conclusions: Irregular (>5 mm), circumferential and complete mucosal appearance are associated with an increased risk for sinus outflow obstruction and an ENT consultation is recommended. A rounded mucosal appearance of any grade is associated with a low risk for sinus obstruction. Routine CT scans, including the maxillary sinus ostium, are recommended.
To cite this article:
Carmeli G, Artzi Z, Kozlovsky A, Segev Y, Landsberg R. Antral computerized tomography pre-operative evaluation: relationship between mucosal thickening and maxillary sinus function.
Clin. Oral Impl. Res. 22, 2011; 78–82.
doi: 10.1111/j.1600-0501.2010.01986.x
TL;DR: Radiographic bone defect depth was linked to histological observations of the peri-implant bone, and CBCT was not found to be reliable for bone density measures, but might hold potential with regard to the structural analysis of the trabecular bone.
Abstract: Objectives: The present study aims to identify radiographic methods revealing data that are most representative for the true peri-implant bone as assessed by histology.
Materials and methods: Eighty implants were placed in 10 minipigs. To assess matching between different image modalities, measurements conducted on intra-oral digital radiographs (IO), cone beam computer tomography (CBCT) and histological images were correlated using Spearman's correlation. Paired tests (Wilcoxon test) were used to determine changes in the bone parameters after 2 and 3 months of healing.
Results: Significant correlations between bone defect depth on IO and histological slices (r=+0.7, P<0.01), as well as on CBCT images and histological slices (r=+0.61, P<0.01), were found. CBCT and IO images deviate, respectively, 1.20 and 1.17 mm from the histology regarding bone defects. No significant correlations were detected between fractal analysis on CBCT, intra-oral radiography and histology. For bone density assessment, significant but weaker correlations (r=+0.5, P<0.01) were found for intra-oral radiography vs. histology. Significant marginal bone-level changes could be observed after 3 months of healing using intra-oral radiography.
Conclusions: This study allowed linking radiographic bone defect depth to the histological observations of the peri-implant bone. Minute bone changes during a short-term period can be followed up using digital intra-oral radiography. Radiographic fractal analysis did not seem to match histological fractal analysis. CBCT was not found to be reliable for bone density measures, but might hold potential with regard to the structural analysis of the trabecular bone.
To cite this article:
Corpas LS, Jacobs R, Quirynen M, Huang Y, Naert I, Duyck J. Peri-implant bone tissue assessment by comparing the outcome of intra-oral radiograph and cone beam computed tomography analyses to the histological standard
Clin. Oral Impl. Res. 22, 2011; 492–499
doi: 10.1111/j.1600-0501.2010.02029.x