bluuebunny/crossref_metadata_2025 huggingface dataset:
Subretinal pigment dispersion following transpupillary thermotherapy for choroidal melanoma
Authors: Kiratli Hayyam , Bilgiç Sevgül
Published: March 2003

Purpose:  To report the case of a patient who developed considerable subretinal pigment/debris dispersion following transpupillary thermotherapy (TTT). This type of tumour response is extremely rare with this relatively new therapeutic modality.

Methods:  A 50‐year‐old man with a left juxtapapillary choroidal melanoma measuring 8 × 6 × 4.3 mm was treated with 810 nm diode laser TTT administered in two sessions. Spot size was 3 mm and the power setting was 450 mW.

Results:  Four months after the first treatment session, a considerable amount of pigment/debris was seen to have dispersed in the subretinal space, accumulating mainly in the macular area. Over a 12‐month follow‐up, the tumour showed progressive shrinkage without any change in the amount or location of the shed pigment/debris. No new tumour formation, recurrence or systemic metastases were detected.

Conclusion:  Subretinal pigment/debris dispersion is an unusual complication after TTT and requires close follow‐up. There has been no short‐term compromise on the life or visual acuity of this patient.
Pilot study on the time course of apoptosis in the regenerating corneal epithelium
Authors: Estil Svein , Kravik Katherine , Haaskjold Erling , Refsum Sigvald B. , Bjerknes Rolf , Wilson Graeme
Published: March 2003

Purpose:  To determine whether apoptosis contributes to regeneration of the corneal epithelium following erosion and following ultraviolet irradiation.

Methods:  Central corneal erosions were made on one eye of 16 rats. One eye of another set of 16 rats was exposed to UVB irradiation. The rats were killed at time intervals varying from 12 hours to 7 days after treatment. Enucleated eyes were fixed in buffered formaldehyde and evaluated by terminal deoxynucleotidyl transferase‐mediated deoxyuridinetriphosphate (dUTP) nick‐end labelling (TUNEL) and morphology. The total number of cells and the number of TUNEL positive cells were counted in perpendicular sections using light microscopy.

Results:  Following central erosion the total epithelial cell number was restored by day 3. During the first 5 days, TUNEL positive cells were observed only in small numbers, but an increase occurred by days 6 and 7. After UVB, an increase in TUNEL positive cells was noted for at least 3 days, and by day 7 there was a small increase of TUNEL positive cells. This differed from the results seen in control animals.

Conclusions:  The present study indicates that after injury, apoptosis occurs in two distinct phases. There is an initial early phase of apoptosis which subsides at about the time the cell mass is being restored and after damaged cells have been removed. A later phase of apoptosis occurs suggests it has a homeostatic role which contributes to the regulation of the cell population.
A comparison of glaucoma patients identified through mass screening and in routine clinical practice
Authors: Grødum Kirsti , Heijl Anders , Bengtsson Bo
Published: March 2003

Purpose:  To study differences between glaucoma patients identified through a population screening and glaucoma patients diagnosed in routine clinical practice (self‐selected patients).

Methods:  A total of 402 individuals with newly detected open‐angle glaucoma were identified through a large population screening programme that ran from October 1992 to January 1997. The screening programme was attended by a total of 32 918 citizens of Malmö, Sweden, aged between 57 and 79 years. Citizens who had visited the Eye Department of Malmö University Hospital in the year before the screening of their birth cohort were not invited to participate (n = 4117). Among the latter, we identified 354 patients with open‐angle glaucoma through a retrospective examination of patient records.

Results:  At detection, 52.9% of the glaucoma patients identified through screening had normal tension glaucoma (NTG), defined as intraocular pressure (IOP) < 21 mmHg in both eyes, compared to 13.5% of the self‐selected patients (p < 0.0001). Mean IOP at the time of diagnosis was 22.9 mmHg in the screened group and 32.5 mmHg in the self‐selected group. Pseudoexfoliation was present in 16.4% of the screened group and 44.0% of the self‐selected group (p < 0.01). Bilateral disease was present in 40.1% of the screened group and 34.6% of the self‐selected group (p = 0.1160). Median MD (mean deviation from the age‐corrected normal visual field) in the worse eye was −8.0 dB in the screened group and −16.2 dB in the self‐selected group (p < 0.0001). Visual acuity was lower in the self‐selected group, which was also on average slightly more myopic. Of the patients detected through screening, 62% had seen an ophthalmologist previously, 17% within the preceding 2‐year period.

Conclusions:  Normal tension glaucoma was four times as common in patients identified through population screening as in self‐selected patients, suggesting that patients with NTG are easily overlooked in clinical practice. Even though the patients detected through population screening had lower mean IOP, lower prevalence of pseudoexfoliation, better visual fields and a lower incidence of bilateral disease than self‐selected patients, many still had considerable damage. Special efforts, such as glaucoma screening, are needed if manifest glaucoma, and especially NTG, is to be detected at an earlier stage than it currently is.
Selection of dairy bacterial strains as probiotics for oral health
Authors: Comelli Elena Maria , Guggenheim Bernhard , Stingele Francesca , Neeser Jean‐Richard
Published: March 2003

The aim of the present study was to select bacterial strains with potential properties as oral probiotics, namely for the prevention of dental caries. We examined 23 dairy microorganisms, out of which we identified two Streptococcus thermophilus and two Lactococcus lactis strains that were able to adhere to saliva‐coated hydroxyapatite beads to the same extent as Streptococcus sobrinus OMZ176. Two of them, Strep. thermophilus NCC1561 and Lactoc. lactis ssp. lactis NCC2211, were further successfully incorporated into a biofilm mimicking the dental plaque. Furthermore, they could grow in such a biofilm together with five strains of oral bacterial species, representative of supragingival plaque. In this system, Lactoc. lactis NCC2211 was able to modulate the growth of the oral bacteria, and in particular to diminish the colonization of Streptococcus oralis OMZ607, Veillonella dispar OMZ493, Actinomyces naeslundii OMZ745 and of the cariogenic Strep. sobrinus OMZ176. These findings encourage further research with selected non‐pathogenic dairy bacterial strains with the aim to decrease the cariogenic potential of dental plaque.
Ets‐1 and integrin beta3 for lung metastasis from colorectal cancer
Authors: Sato Takahiro , Miwa Atsuo
Published: March 2003

Ets‐1 functions as tissue‐specific transcription factor and plays an important role in cell proliferation, differentiation, angiogenesis, and apoptosis. To elucidate the involvement of Ets‐1 in lung metastasis from colorectal cancer, immunohistochemical analysis was performed on 51 colorectal cancer patients (22 with lung metastasis and 29 with advanced colorectal cancer showing no recurrence for at least 5 years after surgery). Tumorous and stromal Ets‐1 immunoreactivity was evaluated. Ets‐1 protein was demonstrated within stromal fibroblasts, myofibroblasts and capillaries, and also within carcinoma cells. Stromal Ets‐1 immunoreactivity in primary colorectal cancer was statistically correlated with lung metastasis (p<0.05). In primary colorectal cancer, a significant association was observed between stromal Ets‐1 immunoreactivity and vascular integrin beta3 expression (p<0.01). In the cases with lung metastasis, vascular integrin beta3 index in lung metastases was significantly diminished compared with primary tumors or liver metastases (p<0.01). In contrast, stromal or tumorous Ets‐1 expression did not change. In a multivariate model using logistic stepwise regression analysis, vascular integrin beta3 and stromal Ets‐1 overexpression were significantly and independently related to lung metastasis. Stromal Ets‐1 and/or vascular integrin beta3 may be useful markers for risk of lung metastasis from colorectal cancer.
Bax, Bcl‐2, Fas and Fas‐L antigen expression in human seminoma: Correlation with the apoptotic index
Authors: GROBHOLZ RAINER , ZENTGRAF HANSWALTER , KÖHRMANN KAI‐UWE , BLEYL UWE
Published: March 2003

Apoptosis plays a crucial role in the regulation of spermatogenesis in male germ cells and is, at least in part, modulated by Bcl‐2, Bax, and the Fas pathway. Seminomas have a favourable outcome and respond to radio‐/chemotherapy with an increased rate of apoptosis. The expression of Bax, Bcl‐2, Fas and Fas‐ligand (Fas‐L) in human seminoma was evaluated and correlated with the apoptotic index.

Twenty‐nine classical seminomas were examined by immunohistochemistry and Western blotting using antibodies against Bax, Bcl‐2, Fas and Fas‐L. Apoptosis was detected by in‐situ end‐labeling of fragmented DNA and the apoptotic index (AI) was determined.

Expression of Fas was found in 26 (89.7%) of Fas‐L in 24 seminomas (82.2%); none of the tumours expressed Bcl‐2. No correlation between the AI and Fas, Fas‐L or Bcl‐2 expression was found. Bax was demonstrated in 20/29 tumours (69%). Bax‐positive tumours showed an increased AI of 4.75±2.38% in contrast to 2.60±1.23% of the Bax‐negative tumours (P=0.002). The number of Bax‐positive tumour cells and apoptotic cells revealed a significant correlation using χ2‐test (P=0.04) and linear regression (r=0.54, P=0.001).

Therefore, Bax seems to play a determinant role in the modulation of apoptosis in human seminoma that may be linked to a favourable outcome.
Identification of randomly selected colonies of lactobacilli from normal vaginal fluid by pyrosequencing of the 16S rDNA variable V1 and V3 regions
Authors: TÄRNBERG MARIA , JAKOBSSON TELL , JONASSON JON , FORSUM URBAN
Published: March 2003

The present study aimed to characterize lactobacilli in vaginal fluid from 23 adult healthy women by using high‐throughput DNA sequencing for identification of a large number of randomly selected colonies appearing on Rogosa and blood agar. The typing method was based on broad‐range PCR of 16S rRNA gene variable regions V1 and V3, pyrosequencing, and classification of the fragments by alignment with NCBI‐catalogued sequences and type strain sequences. Four major groups of sequences were found among the 402 isolates clearly corresponding to Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus iners and Lactobacillus jensenii when compared to the sequences obtained for type strains. Our results indicate that pyrosequencing of 16S rRNA gene fragments as used here is a fast and reliable method well suited for identification to the species level, even within the Lactobacillus acidophilus complex.
The reliability of pocket probing around screw‐type implants
Authors: Quirynen M. , Van Steenberghe D. , Jacobs R. , Schotte A. , Darius P.
Published: March 2003

This study involved 108 patients (age 38–82 years) rehabilitated with overdentures in the lower jaw supported by 2 endosseous screw‐shaped implants. At each follow‐up visit, the clinical attachment level (PAL) around the implants was assessed with a Merrit‐B probe or a constant force electronic probe, Peri‐probe, and biannually parallel long‐cone radiographs were taken to locate the marginal bone level. These data were used to examine the relationship between bone and attachment level estimations around implants. As a mean, bone level was scored 1.4 mm apically of PAL and this difference remained constant with time. The Pearson correlation coefficient between bone level and PAL, for mesial and distal sites, was 0.67 and 0.61 for the Merrit‐B probe, and 0.76 and 0.65, respectively for the Peri‐probe. The highest correlations were obtained for sites with a healthy gingiva or in absence of intra‐bony craters. Duplicate PAL registrations showed a standard deviation for the intra‐examiner variability of 0.37 (Peri‐probe) or 0.40 mm (Merrit‐B probe) with more than 90% of the variation within 0.5 mm. The mean difference in PAL between Merrit‐B probe or Peri‐probe was 0.05 mm. It was concluded that the clinical attachment level determination is a reliable indicator for bone level around implants with a moderate healthy gingiva.
Implants in partially edentulous patients. A longitudinal study of bridges supported by both implants and natural teeth.
Authors: Gunne J. , Åstrand P. , Ahlén K. , Borg K. , Olsson M.
Published: March 2003

The aim of the study was to compare the outcome of bridges supported by implants with bridges supported by a combination of implants and natural teeth abutments. The study comprised 23 patients with Applegate Kennedy Class I dentition in the mandible and a full upper denture. Implants ad modum Brånemark were inserted in the posterior areas of both mandibular quadrants. On one side, a bridge supported by 2 implants was constructed (Type I) and on the other side, a bridge supported by 1 tooth (mostly the canine or first premolar) and 1 implant was made (Type II). A total of 46 bridges were made and during the 3‐year follow‐up period, 4 Type I and 2 Type II bridges were lost. 8 out of 69 implants were lost during the 3‐year follow‐up, resulting in an implant survival rate of 88.4%. Marginal bone loss, one of several parameters, was evaluated on standardized intraoral radiographs. This was performed during the 1st and 2nd year of function and the total mean bone loss from loading was 0.46 mm and 0.56 mm, respectively. The bone loss during the 2nd year of function was significantly less, adjacent to implants supporting Type II bridges, than adjacent to implants supporting Type I bridges. Summarily, no disadvantages of combining of teeth and implants in the same bridge were found in this study. On the contrary, the slightly lower marginal bone loss adjacent to implants in Type II bridges may indicate that the bone reactions could be more favorable when bridges 1 are connected to both implants and teeth.
Histomorphometric and removal torque analysis for TiO2hyphen;blasted titanium implants. An experimental study on dogs.
Authors: Gotfredsen Klaus , Nimb Lars , Hjörting‐hansen Erik , Jensen Jørgen Steen , Holmén Anders
Published: March 2003

The aim of the present study was to compare the anchorage of TiO2‐blasted screw and cylindrical implants with conventionally used machine‐produced screw and cylindrical implants inserted immediately in extraction sockets on dogs. 6 adult mongrel dogs had 3rd and 4th mandibular premolars extracted bilaterally and 24 commercial pure titanium implants were placed immediately in extraction sockets and covered with mucoperiosteum. Each dog had inserted 4 implants: 1 screw implant and 1 cylindrical implant blasted with titanium‐dioxide‐particles; 1 screw implant and 1 cylindrical implant with machine‐produced (m.p.) surface (controls). After a healing period of 12 weeks, 16 implants from 4 animals were used for removal torque test, which demonstrated that significantly higher removal torque force was needed to unscrew the implants blasted with titanium‐dioxide‐particles, than the normal m.p. implants. The medians for the TiO2‐blasted screw and cylindrical implants were > 150 Ncm and 10.5 Ncm, respectively, while the values for the m.p. implants were 60 Ncm and 35 Ncm, respectively. The SEM investigation demonstrated a high irregularity of the TiO2‐blasted surface compared to the machined surface. The R, and R, values for surface roughness were higher for the TiO2‐blasted implants than for the normal m.p. implants. Histomorphometrically, the arithmetic mean of the direct bone‐implant contact fraction was 69%. There was no significant difference in direct bone‐implant contact length fraction between TiO2‐blasted implants and the control implants. The implants blasted with titanium‐dioxide‐particles in this study showed a better anchorage than implants with a machine‐produced surface. The screw implants showed a better anchorage than the cylindrical implants.
Application of magnetron sputtering for producing ceramic coatings on implant materials
Authors: Jansen J. A. , Wolke J. G. C. , Swann S. , Van Der Waerden J. P. C. M. , De Groof K.
Published: March 2003

Radiofrequent magnetron sputtering was used to produce calcium phosphate coatings on metal and plastic substrates. Scanning electron microscopy showed that the deposited films had a uniform thickness and a dense columnar structure. Energy‐dispersive X‐ray analysis, X‐ray crystal diffraction and atomic absorption spectrometry demonstrated that the sputtered layer was well‐crystallized calcium phosphate ceramic with a Ca/P ratio varying between 1.9 and 2.5. The biocompatibility of the coatings was determined by in vitro and in vivo experiments. It was found that the coatings were biocompatible without any sign of adverse tissue reaction. It was concluded that magnetron sputtering is a promising method for forming a biocompatible ceramic coating onto an implant material. Nevertheless, several problems have to be solved before magnetron sputtering can be used on a routine basis for the production of Ca/P coatings.
Guided tissue regeneration using degradable and nondegradable membranes in rabbit tibia
Authors: Aaboe M. , Pinholt E. M. , Hjørting‐hansen E. , Solheim E. , Praetorius F.
Published: March 2003

Three different membranes were tested for guided bone regeneration in 8‐mm unicortical trephine defects in rabbit tibia. All experimental and control defects healed with bone. The critical size defect in rabbit tibia is larger than 8 mm, because control defects, 8 mm in diameter, healed spontaneously. Around remnants of the biodegradable Polyglactin 9 10 mesh (Vicryl®). a diffuse infiltration of inflammatory cells with multinuclear giant cells developed. However, the bone healing was not impaired by the infiltrate. Around the Gore‐Tex® membrane and around remnants of the Alzamer® a few lymphocytes were observed, but no multinuclear giant 1 cells were noted.
Photogrammetric measurements of implant positions. Description of a technique to determine the fit between implants and superstructures.
Authors: Lie A. , Jemt T.
Published: March 2003

A photogrammetric technique was designed to measure the position of dental implants in 3 dimensions to enable assessment of the tit of superstructures placed on the implants. A relatively simple camera setup was developed and tested. Calibration of the camera was performed in a high‐precision analytical plotter and revealed a film measurement accuracy of 0.005 mm. The achieved measuring accuracy for clear and well defined points on clinical components was found to be around 0.02 mm. To find the center points of the implants, points on the circumference were measured. These points are not well defined, which resulted in an estimation of the center point of the implant with a precision of 0.05 mm. Independent measurements of a prosthesis with 5 implants were also within the precision of 0.05 mm. The angular orientation of the top surface of the implant cylinder (abutment, brass replica of gold alloy cylinder of the framework) was measured with a precision of 0.01 radians, which corresponded to an error with a peripheral gap of about 0.03 mm. This value was about 5‐10 times lower than the clinical fit between frameworks and abutments, measured in 3 randomly selected clinical cases.
Clinical and radiographical features of submerged and nonsubmerged titanium implants
Authors: Ericsson I. , Randow K. , Glantz P.‐O. , Lindhe J. , Nilner K.
Published: March 2003

A clinical and radiographical study was performed to evaluate whether initial submergence of titanium fixtures is an obligate treatment measure for the establishment of proper bone anchorage when implants a.m. Brånemark are used. The sample was comprised of 11 subjects with edentulous mandibles. A split‐mouth design was employed; in the right mandibular quadrant a traditional 2‐step procedure for fixture installation and abutment connection was utilized, while in the left quadrant a 1‐step procedure was carried out, i.e., fixtures were placed and abutments were connected in one and the same session. Three to 4 months after fixture installation, fixed bridgeworks were fabricated and rigidly connected to the implants. Clinical examinations (including probing pocket depth, bleeding on probing and implant stability test) were performed after 12 and 18 months. Radiographs were taken following insertion of the bridges and at the 12‐ and 18‐month re‐examinations. The probing pocket depth, the bleeding on probing, the implant stability and the radiographic determinations were similar for the 2 groups of treatment alternatives. This indicates that titanium fixtures a.m. Brinemark can be properly anchored (osseointegrated) in mandibular bone and successfully used for bridge retention also when a 1‐step procedure is used for implant installation.
Formation of jawbone tuberosities by guided tissue regeneration. An experimental study in the rat.
Authors: Kostopoulos L. , Karring T. , Uraguchi R.
Published: March 2003

The aim of this study was to explore the possibility of creating bone tuberosities on the mandibular ramus in rats, using a rigid, occlusive. Teflon capsule. The experiment was carried out in 30 rats. The mandibular ramus was exposed bilaterally. On the test side, the periosteum was left covering the lateral surface of the ramus. On the contralateral side (control). the periosteum was elevated from the lateral surface together with the flap. A hemispherical, Teflon capsule was then placed to face the periosteum or the bone surface with its open part before closure of the wound. The healing periods comprised 7–120 days. Histological analysis demonstrated increasing bone fill in the test specimens from 7 to 60 days, and a limited further increase was observed from 60 to 120 days. In the control specimens, limited bone fill was seen within the first month after surgery, but substantial amounts of new bone were produced from 30–120 days. At 120 days, the mean amount of bone obtained in the test specimens was 56%(range 39%‐71%) of the total space created by the capsules, and it was 52%(range 32%‐85%) in the controls. The amount of newly formed bone was equivalent to a 5–6 times increase of the original width of the mandibular ramus. These findings indicate that a secluded space created by an occlusive barrier adjacent to existing bone or periosteum may be filled out with bone tissue. This may have a great clinical impact in cranial and maxillofacial surgery.
Proliferation, differentiation, and protein synthesis of human osteoblast‐like cells (MG63) cultured on previously used titanium surfaces
Authors: Martin J. Y. , Dean D. D. , Cochran D. L. , Simpson J. , Boyan B. D. , Schwartz Z.
Published: March 2003

This study compared osteoblast proliferation, differentiation, and protein synthesis on new and used titanium (Ti) disks to test the hypothesis that cleaning and resterilization of previously used Ti disks does not alter cell response to a particular surface. Ti disks of varying roughness were prepared by one of five different treatment regimens. Standard tissue culture plastic was used as a control. Human osteoblast‐like cells (MG63) were cultured on the Ti disks and cell proliferation, cell differentiation, RNA synthesis and matrix production (collagen and noncollagen protein; proteoglycans) measured. After their first use, the disks were cleaned, re‐sterilized by autoclaving. and MG63 cells cultured on them as before. At confluence, the same parameters were measured and cell behaviour on new and used disks compared. When confluent cultures of cells on plastic were compared to those cultured on new Ti surfaces, cell number was reduced on the roughest surfaces and equivalent to plastic on the other surfaces. Cell number was further reduced when disks with the roughest surfaces were re‐used; no differences in cell number could be discerned after cleaning and re‐sterilization. Cell proliferation was inversely related to surface roughness and was less than seen on tissue culture plastic. Re‐use of the Ti disks resulted in no change in cell proliferation rate. Alkaline phosphatase specific activity in isolated cells was lowest on the rougher surfaces; no differences between new and used disks were observed. Similarly, enzyme activity in the cell layer was decreased in cultures grown on rougher surfaces, with no effect of prior disk use being noted. RNA synthesis was decreased with respect to plastic in cultures on smoother surfaces and increased on rougher surfaces; prior disk use did not alter RNA synthesis. Collagen production by the cells was decreased on smoother surfaces, but was comparable to tissue culture plastic when grown on rougher surfaces. Non‐collagen protein production was unaffected by culture surface and whether or not the disk had been previously used. Proteoglycan synthesis by cells was decreased on all surfaces studied and comparable on both new and used disks. The results of this study indicate that Ti implant surfaces are unaffected by cleaning and resterilization, although rougher surfaces may require more extensive cleaning than smoother ones. This suggests the possibility that implants, in the same patient, could be safely reused. In vivo studies in animals, however, need to be performed before clinical application can be considered.
Recession of the soft tissue margin at oral implants. A 2‐year longitudinal prospective study.
Authors: Bengazi Franco , Wennström Jan L. , Lekholm Ulf
Published: March 2003

The aim of this study was to longitudinally evaluate alterations in the position of the peri‐implant soft tissue margin, occurring during a 2‐year period after insertion of fixed prostheses. 41 patients, subjected to treatment with partial or full‐arch implant supported fixed prostheses based on a total of 163 standard Brånemark oral implants, were included in the study. A baseline examination was performed at time of insertion of the prosthetic construction and involved assessments of plaque, mucositis, probing depth, bleeding on probing, marginal soft tissue level, width of masticatory mucosa and marginal soft tissue mobility. All patients were re‐examined after 6 months, and after 1 and 2 years, respectively. A regression analysis was performed to evaluate if alterations, occurring in the position of the periimplant soft tissue margin during the 2 years, could be predicted by various variables recorded at time of the installation of the fixed prosthesis. The descriptive analysis showed a slight decrease in mean probing depth (0.2mm) and width of masticatory mucosa (0.3mm) during the follow‐up period. Apical displacement of the soft tissue margin mainly took place during the first 6 months of observation. Lingual sites in the mandible showed the most pronounced soft tissue recession, decrease of probing depth, and decrease of width of masticatory mucosa. The statistical analysis revealed that lack of masticatory mucosa and mobility of the periimplant soft tissue at time of bridge installation were poor predictors of soft tissue recession occurring during the 2 years of follow‐up, but indicated a greater amount of recession in women than men, in the mandible than in the maxilla, at lingual than at facial sites and with increased initial probing depth. It was suggested that the recession of the periimplant soft tissue margin mainly may be the result of a re‐modelling of the soft tissue in order to establish “appropriate biological dimensions” of the periimplant soft tissue barrier, i.e. the required dimension of epithelial‐connective tissue attachment in relation to the facio‐lingual thickness of the supracrestal soft tissue.
A prospective 15‐year follow‐up study of mandibular fixed prostheses supported by osseointegrated implants. Clinical results and marginal bone loss.
Authors: Lindquist L. W. , Carlsson G. E. , Jemt T.
Published: March 2003

In this prospective study 47 edentulous patients were treated with mandibular fixed prostheses supported by osseointegrated Brånemark implants and followed for 12 to 15 years. Three 1%) of the 273 inserted implants were lost, two before and one six years after placement of the fixed prosthesis. The cumulative success rate CSR) of the implants was 98.9% both after 10 and 15 years. None of the fixed prostheses was lost and at the last follow‐up, all patients had stable fixed prostheses in function (CSR 100%). The marginal bone loss around the implants was small, on average 0.5mm during the first post surgical year and thereafter about 0.05mm annually. More bone was lost around the anterior implants than around the most posterior ones. Smoking and poor oral hygiene had significant influence on bone loss, while occlusal loading factors such as maximal bite force, tooth clenching and length of cantilevers were of minor importance. It is concluded that the long‐term results of the mandibular implant treatment were extremely successful, regarding both the fixed prostheses and implant stability. Bone resorption around the implants, albeit limited, was influenced by several factors, smoking and oral hygiene appeared to be most important.
Mandibular overdentures supported by two Brånemark, IMZ or ITI implants. A prospective comparative preliminary study: One‐year results.
Authors: Batenburg Rutger H. K. , Meijer Henny J. A. , Raghoebar Gerry M. , Van Oort Robert P. , Boering Geert
Published: March 2003

The aim of this prospective comparative study was to evaluate the condition of the peri‐implant tissues of three different implant systems supporting a mandibular overdenture. Ninety edentulous patients (Cawood class V–VI) participated in this study. After randomization, 30 patients were treated with 2 Brånemark implants, 30 patients with 2 IMZ implants and 30 patients with 2 ITI implants. The implants were inserted in the canine region of the mandible. After 3 months overdentures were fabricated supported by a round bar and clip attachment. A standardized clinical and radiographic evaluation was performed 0,6 and 12 months after insertion of the denture. The intra‐oral radiographs were made, using the long‐cone technique with an aiming device. Two implants were lost (1 Brånemark, 1 IMZ) during the healing period. None of the patients showed any sensory change in lip or chin region. The pocket depth in the Brinemark group decreased significantly whereas the mucosa recession increased significantly in both the Brånemark as well as in the IMZ group. After 12 months, there was significantly less bone loss in the ITI group. From our study it was concluded that 2 (Brånemark, IMZ or ITI) implants placed in the interforaminal region connected with a bar supply a proper base for the support of a mandibular overdenture in the (Cawood V–VI) edentulous patient. The ITI implant appears to be the implant of choice for mandibular overdenture therapy. because only one operation is required for a comparable result.
Long‐term evaluation of non‐submerged ITI implants. Part 1: 8‐year life table analysis of a prospective multi‐center study with 2359 implants.
Authors: Buser Daniel , Mericske‐stern Regina , Pierre Bernard Jean Pierre , Behneke Alexandra , Behneke Niklaus , Hirt Hans Peter , Belser Urs C. , Lang Niklaus P.
Published: March 2003

In the present multi‐center study. non‐submerged ITI implants were prospectively followed to evaluate their long‐term prognosis in fully and partially edentulous patients. In a total of 1003 patients, 2359 implants were consecutively inserted. Following a healing period of 3–6 months, the successfully integrated implants were restored with 393 removable and 758 fixed restorations. Subsequently, all consecutive implants were documented annually up to 8 years. At each examination, the clinical status of all implants was evaluated according to predefined criteria of success. Therefore, the data base allowed the evaluation of 8‐year cumulative survival and success rates for 2359 implants. In addition, cumulative success rates were calculated for implant subgroups divided per implant type, implant length. and implant location. Furthermore, the actual 5‐year survival and success rates could be determined for 488 implants. During the healing period, 13 implants did not successfully integrate, whereas 2346 implants fulfilled the predefined criteria of success. This corresponds with an early failure rate of 0.55%. During follow‐up, 19 implants were classified as failures due to several reasons. In addition, 17 implants (= 0.8%) demonstrated at the last annual examination a suppurative periimplant infection. Including 127 drop out implants (= 5.4% drop out rate) into the calculation, the 8‐year cumulative survival and success rates resulted in 96.7% and 93.3%, respectively. The analysis of implant subgroups showed slightly more favorable cumulative success rates for screw type implants (> 95%) compared to hollow‐cylinder implants (91.3%). and clearly better success rates for mandibular implants (= 95%) when compared to maxillary implants (= 87%). The actual 5‐year survival and success rates of 488 implants with 98.2% and 97.3%. respectively, were slightly better than the estimated 5‐year cumulative survival and success rates of 2359 implants indicating that the applied life table analysis is a reliable statistical method to evaluate the long‐term prognosis of dental implants. It can be concluded that non‐submerged ITI implants maintain success rates well above 90% in different clinical centers for observation periods up to 8 years.
Influence of surface treatments developed for oral implants on the physical and biological properties of titanium. (II) Adsorption isotherms and biological activity of immobilized fibronectin.
Authors: François P. , Vaudaux P. , Taborelli M. , Tonetti M. , Lew D. P. , Descouts P.
Published: March 2003

The influence of titanium surface properties on in vitro adsorption isotherms of tibronectin, promotion of Staph;lococcus aureus adhesion, and binding of a monoclonal antibody to the cell‐binding domain of fibronectin was examined. Treatments producing different surface roughness were applied to a single side of commercially pure titanium coverslips, which was either mechanically polished (P), or polished and then acid attacked with H2SO4/HCI (PA), or sandblasted and then acid attacked (SLA), whereas the untreated side was blocked by an albumin coating layer. Incubation of the coverslips with concentrations of soluble 3H‐labelled fibronectin increasing from 1 to 16 μg/ml led to the saturation of all surfaces with immobilized protein from 4 to 16 μg/ml. Promotion of S. aureus adhesion by fibronectin adsorbed on all surfaces and binding of the monoclonal antibody to its cell‐binding domain was to some extent proportional to the amount of immobilized protein but also showed some minor differences between surfaces. More important material‐related differences were observed when fibronectin adsorption isotherms were expressed as a function of the effective, roughness‐corrected surface area, yielding amounts of immobilized fibronectin on the rough PA and SLA titanium surfaces which were 50% lower than those adsorbed on either smooth P or polymethylmethacrylate coverslips used as controls. In conclusion, surface treatments increasing the surface roughness of titanium do not increase, but may partly decrease in vitro adsorption of fibronectin. Despite adsorbing different amounts of fibronectin, both rough and smooth titanium surfaces promote normal expression of 2 major functional domains of this protein.
Periodontal parameters of osseointegrated dental implaits. A 4‐year controlled follow‐up study
Authors: Nishimura Kenji , Itoh Takatoshi , Takaki Kimiyasu , Hosokawa Ryuji , Naito Toru , Yokota Makoto
Published: March 2003

The aim of this study was to evaluate the periodontal parameters of osseointegrated dental implants. The condition of the peri‐implant mucosa was assessed using periodontal parameters, i.e., of plaque index, bleeding on probing, probing pocket depth, probing attachment level and Periotest® scores as well as a radiographic parameter, over a 4‐year follow‐up period. 32 non‐submerged ITI dental implants, all placed in the mandible, were studied in 12 patients who had good oral hygiene. All patients were regularly recalled at 6‐month intervals. The overall implant success rate was 100%. None of the implants showed any signs of inflammation, radiographic bone loss or any detectable mobility during the follow‐up period. Methods similar to those used to evaluate the natural dentition were effectively employed to assess the clinical status of the dental implants. The diagnostic value of these parameters could not, however, be determined from this study due to the absence of any peri‐implant tissue complications. The results indicated that some periodontal parameters of healthy peri‐imolant mucosa might be slightly different from healthy periodontal tissue.
Custom‐made root analogue titanium implants placed into extraction sockets. An experimental study in monkeys.
Authors: Kohal Ralf‐J. , Hürzeler Markus B. , Mota Luis F. , Klaus Gerold , Caffesse Raul G. , Strub Jörg R.
Published: March 2003

The aim of this investigation was to evaluate clinically and histologically a new custom‐made, root analogue titanium implant placed into extraction sockets in monkeys (Macaca fascicularis). Three adult monkeys were used in this investigation. After raising full thickness flaps on the buccal and lingual side, the upper central and lateral incisors were extracted. Each tooth root was machine copied to 1 titanium analogue using a new CAD/CAM‐system. The implants were installed in the respective extraction sockets and the flaps sutured back. After 6 months of healing biopsies were taken and processed according to the cutting‐grinding technique. The percentage of mineralized bone‐to‐implant contact was measured as a fraction of the rough implant surface using computer‐assisted analysis. The main clinical problem that occurred during implant placement was the fracture of the buccal alveolar wall. The histometric evaluation showed a mean mineralized bone‐to‐implant contact of 41.2±20.6%. In this investigation it could be shown that implants fabricated by laser copying will osseointegrate. The presented data encourage the performance of clinical and experimental trials evaluating the new system utilizing improved second generation CAD/CAM equipment. Such studies are currently underway.
Maxillary sinus augmentation using different grafting materials and osseointegrated dental implants in monkeys. Part II. Evaluation of porous hydroxyapatite as a grafting material.
Authors: Quiñones Carlos R. , Hürzeler Markus B. , Schüpbachs Peter , Kirsch Axel , Blum Petra , Caffesse Raul G. , Strub Jörg R.
Published: March 2003

The aim of this study was to evaluate clinically, histologically and histometrically the use of porous hydroxyapatite (i.e. Interpore‐200®) as a bone grafting material for maxillary sinus augmentation procedures. In 4 adult male rhesus monkeys (i.e. Macaca mulatto) the lst, 2nd and 3rd maxillary molars on one side of the jaws were extracted and the remaining bone between the alveolar crest and the bottom of the sinus was reduced to 3–4 mm. After 3 months, maxillary sinus augmentation procedures were performed on one side of the jaws in each monkey, and the sinuses grafted with the porous hydroxyapatite. Two IMZ@ titanium plasma‐sprayed cylinder implants were then immediately placed into the augmented sinus (i.e. simultaneous implants‐loaded group). After 4 months. 2 additional similar implants were placed into the previously augmented sinuses (i.e. delayed implants‐loaded group). Four months later, the abutment connection was performed and all 4 implants were loaded with a gold‐alloy bridge for 6 months (i.e. until sacrifice). The contralateral side of each monkey received the same treatment with the exception that the extractions were performed 7 months after those in the opposite side and that the implants in this side were not loaded. Thus, 2 additional study groups (i.e. simultaneous implants‐unloaded group and delayed implants‐unloaded group) were obtained. Clinically, all loaded implants were stable at the day of sacrifice. Histologic analysis demonstrated a significant amount of new bone formation in the augmented sinuses. Porous hydroxyapatite graft particles appeared to be integrated to the new bone. The percentage of direct mineralized bone‐to‐implant contact in the augmented area was greater on the delayed‐placed implants than on the simultaneously‐placed implants. Also, the percentage of direct mineralized bone‐to‐implant contact was greater in the residual bone than in the augmented area. It was concluded that this porous hydroxyapatite bone graft enhanced bone formation and bone‐to‐implant contact in the augmented sinuses and that the delayed implant placement in combination with the sinus augmentation procedure appears to result in a higher percentage of direct mineralized bone‐to‐implant contact.
Complication rate with prosthodontic reconstructions on ITI and IMZ dental implants
Authors: Behr Michael , Lang Reinhold , Leibrock Alexander , Rosentritt Martin , Handel Gerhard
Published: March 2003

The aim of this study was to compare the complication rate of two implant systems with diffcrcnt prosthodontic concepts: rigid conical or rcsilicnt support of the suprastructure. In 66 patients, 138 ITI implants were inserted whereas 31 patients received a total of 50 IMZ implants. Over an average observation period of 3.5 years (range from 0.5 to 8 years), not only was implant survival recorded, but also prosthodontic complications such as screw loosening, fractures of screws, inserts (intramobile elements, intramobile connectors) and abutments, as well as fractures of metal framework and veneers. With the ITI system, 28.8% of all devices placed exhibited such problems during the observation period. With the IMZ system, this rate was significantly higher (P<0.05), in that 77.4% of all reconstructions required a repair at some point. The various complications were divided into those occurrences which affected only the suprastructure, i.e., failures of frame‐works, veneers, bar devices or other retentive elements, and those which involved implant components per se, such as screws and abutment components. In the first category, adverse effects occurred more frequently with ITI‐supported prostheses (15.1%) versus IMZ suprastructures (6.4%). Regarding complications with implant components, the rate with IMZ components was considerably higher (71%) compared with ITI (13.5%). This was mainly due to the presence of intramobile elements (IME) and connectors (IMC) in the IMZ system. In this retrospective study, precise fitting, non‐resilient abutment components leading to rigid connections of suprastructures, proved to be clinically more successful than resilient anchoring components.
Complication rate with prosthodontic reconstructions on ITI and IMZ dental implants
Authors: Valentini Pascal , Abensur D. , Densari D. , Grazian J. N. , Hämmerle Christoph
Published: March 2003

Deproteinized cancellous bovine bone (Bio‐Oss®) was placed as a grafting material for sinus floor elevation in the right posterior maxilla. After 6 months of healing, 3 cylindrical titanium‐plasma coated implants were inserted. Six months later at the abutment connection, it was realized that 1 of the implants could not be reconstructed due to unfavorable positioning. This implant was removed along with a small portion of the surrounding peri‐implant tissues. The specimen was processed according to standard techniques for hard tissue histology. In both the grafted area and the previously existing area of the sinus floor the bone was primarily of lamellar structure. Intimate contact between newly formed bone and the particles of the graft was present. No overt signs of resorption of the graft particles were visible. Histomorphometric analysis revealed 63% of implant‐bone contact in the zone of pre‐existing bone, and 73% in the grafted zone. The area density of bone amounted to 27% in the non‐grafted as compared to 28% in the grafted area. In conclusion, this case report documented that deproteinized bovine bone, when used as a grafting material for augmentation of the sinus floor, may lead to proper osseointegration of a dental implant.
Histological morphology of the e‐FTFE/tissue interface in humans subjected to guided bone regeneration in conjunction with oral implant treatment
Authors: Dahlin Christer , Simion Massimo , Nanmark Ulf , Sennerby Lars
Published: March 2003

The purpose of the present investigation was to study the histological morphology of the e‐PTFE membrane/tissue interface in 5 humans subjected to GBR treatment in conjunction with oral implant treatment. Oral implants (Bråemark System®) were inserted in extraction sockets 1 to 2 months after extraction of periodontally diseased teeth. The implants were placed approximately 2 mm below the surrounding bone margins. Specially designed 3 mm high cover‐screws with horizontal slits for tissue ingrowth were applied to the implants and covered with e‐FIFE membranes (GoreTex Augmentation Material). Reentry was made 7 months later, except in 1 case where the membrane was removed 1 month postoperatively due to exposure and infection. In the remaining 4 sites, circular biopsies comprising membranes, tissues and cover‐screws were retrieved. The specimens were fixated, processed and sectioned for light‐ and transmission electron microscopy. The space between the membrane and the cover‐screw was occupied by fibrous tissue and varying amounts of bone. A cell‐ and vessel‐rich fibrous tissue separated the bone from the membrane in the majority of the specimens. The membrane itself was penetrated by fibrous tissue. Fibroblasts and macrophages were the main cell types found in the fibrous issue. The presence of irregularly shaped cells and unevenly distributed collagen fibres, indicated that the absence of bone formation may be due either to micromovements in the e‐PTFE/tissue interface or to formation of fibrous tissue underneath the membrane by penetrating fibroblasts or a combination of these 2 phenomena.
Attachment and proliferation of human oral fibroblasts to titanium surfaces blasted with TiO2 particles. A scanning electron microscopic and histomorphometric analysis.
Authors: Mustafa Kamal , Lopez Blanca Silva , Hultenby Kjeil , Wennerberg Ann , Arvidson Kristina
Published: March 2003

The purpose of this study was to determine the effect of c.p. titanium surfaces blasted with TiO2 particles on the biological responses of human gingival fibroblasts (HGF). Fibroblast morphology and attachment were investigated on turned (control) titanium surfaces and those blasted with 45 μm (standard), 45Ndash;63 μm, and 63–90 μm TiO2 particles. The specimens were analyzed using a confocal laser scanner and SEM. The cell profile areas were measured using a semiautomatic interactive image analyser. The figures were expressed as percent of attachment. The turned samples had the smoothest surfaces and the roughest were those blasted with 63–90 μm. All TiO2 blasted specimens had homogeneous surfaces. Cells appeared to flatten, spread and form cellular bridges with the adjacent cells. Fibroblasts on the turned titanium surfaces appeared to follow the direction of the fine irregularities on the surface but tended to spread haphazardly on the blasted surfaces. The attachment assays showed no significant difference in the percentage of fibroblast cell attachment on the standard surfaces compared to the turned surfaces. Both surfaces blasted with 45–63 μm or 63–90 μm had significantly (P<0.05) lower percentages of cell attachment than the control. The surfaces blasted with 63–90 μm particles had the lowest rate of cell attachment. A significant correlation (P<0.01) was found between the degree of particle size and attachment of fibroblasts after l–72 h. It is concluded that surface micro‐texture influences the attachment and growth of HGF: surfaces blasted with 45 pm TiO, do not inhibit fibroblast attachment and smooth or finely grooved surfaces could be conducive to cellular attachment.