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OBJECTIVES Resonance frequency analysis (RFA) is used to monitor implant stability. Its output, the Implant Stability Quotient (ISQ), supposedly correlates with insertion torque, a common measurement of primary stability. However, the reliability of RFA in condensed bone remains unclear. MATERIAL AND METHODS In this human cadaver study in edentulous jaws and fresh extraction sockets, implants were inserted using a split-mouth approach into condensed or untreated bone. Mean ISQ, peak insertion torque, and pre- and postoperative bone volume fractions (BV/TV) were assessed. RESULTS In edentulous jaws, insertion torque and ISQ correlated both in untreated (r��=��0.63, p��=��0.02) and in condensed (r��=��0.82, p����< 0.01) bone. In extraction sockets, insertion torque and ISQ only correlated in untreated (r��=��0.78, p��

Objectives. The dental alveolus is lined by a thin cortical layer (“bundle bone”, “alveolar bone proper”, “cribriform plate”, “lamina dura”), that can impede access to the bone marrow and its vasculature. During unassisted socket healing, the alveolar bundle bone is gradually resorbed allowing tissue resources from the bone marrow to enter into the socket space. An optimized wound healing process, either during unassisted socket healing or during ridge preservation procedures, with autogenous bone and/or any bone/collagen substitute material, depends at least partly on an adequate vascularization of the socket space. This ensures sufficient recruitment of osteoblast and osteoclast precursor cells and facilitates fast bone regeneration and/or uneventful integration of the augmentation material. Methods. The present technical note describes an easy treatment step after tooth extraction aiming to improve socket healing with or without any ridge preservation procedure, by facilitating an increased blood inflow into the dental alveolus. Specifically, after tooth extraction the alveolar bundle bone is perforated several times – mainly in a palatally/lingually – by a small round bur (diameter < 1 mm) extending into the trabecular bone. Results and conclusions. By means of this relatively simple treatment step, an increased blood inflow into the alveolus is achieved after tooth extraction, which might enhance socket healing and corticalization of the entrance, and in turn result in a lower complication rate (e.g., dry socket), in an enhanced graft incorporation, and/or in a reduced loss of alveolar ridge volume.

Background Maxillary sinus floor augmentation (MSFA) is a well‐established and predictable augmentation method in severely resorbed maxillae. However, data on the vertical course of bone graft consolidation within the maxillary sinus are rare. The aim of the present study was to quantify the vertical distribution of new bone formation (nBF) in MSFA and to characterize the vertical gradient of bone graft consolidation. Methods Eighty‐five human sinus biopsies were harvested 6 ± 1 months after MSFA. Histological thin‐ground sections were prepared and histomorphometrically analyzed. The volume of newly formed bone (nBV/TV) was measured in serial zones of 100 μm proceeding from the bottom of the sinus floor (SF) up to the apical top of the biopsy. The gradient of nBV/TV within the augmentation area was determined by the vertical distribution of nBV/TV along these zones. Results In the premolar region, nBV/TV slightly declined from 20.4% in the zone adjacent to the SF to 17.7% at a distance of 8 mm. The gradient was steeper in the molar region: nBV/TV decreased from 18.7% to 12.8%. This decline was even more distinct when the volume fraction and the height of the residual bone of the SF were low. Conclusions nBF follows a gradient from native bone of the SF towards the apical part of the augmentation area. The distance to primordial bone thus plays a critical role for bone regeneration in MSFA, particularly in the molar region.

OBJECTIVES To assess, retrospectively, whether older age has an impact on implant osseointegration when compared with younger age. METHODS All patients ≥65 years old at implant installation, in an university setting over a time-period of 11.5 years, with complete anamnestic data and follow-up until prosthetic restoration were included, and any early implant loss (EIL; i.e. lack of osseointegration prior to or at the time-point of prosthetic restoration) was recorded. Further, one implant, from each of the elderly patients, was attempted matched to one implant in a younger patient (35 to

Background Elevation of the schneiderian membrane, during maxillary sinus floor augmentation (MSFA) may theoretically result in devitalization of adjacent teeth, which are in a close spatial relationship to the sinus floor. Purpose To assess retrospectively the probability of devitalization of teeth adjacent to the osteotomy site after MSFA in a relatively large number of patients. Materials and methods All MSFA procedures, performed at a university oral surgery clinic within a time period of 10 years, were assessed on the following eligibility criteria: (1) presence of vital teeth (ie, not root canal treated and no periapical radiolucency on a panoramic radiograph taken just after MSFA), (2) presence of a 3 to 12 months postoperative radiograph of the teeth adjacent to the osteotomy site displaying the root apices, and (3) complete medical records up to at least 12 months postoperatively. The radiographs of the different time points were compared and any changes in the radiographic status of the adjacent teeth (eg, development of a periapical lesion, root canal treatment, etc.) were recorded and the spatial relationship of the adjacent teeth to the maxillary sinus classified. Results Out of 684 MSFAs, 257 fulfilled the inclusion criteria and involved 357 adjacent teeth, of which 221 presented close to and/or intimate relationship to the sinus. In only a single case, tooth vitality might have been lost due to the procedure. Thus, the probability for tooth devitalization for teeth with close to and/or intimate spatial relationship to the sinus floor ranged from 0.45% to 0.7%. Conclusions Even for teeth with apices very close to and/or intimately related to the sinus tooth devitalization after MSFA is an extremely rare complication; that is, the probability of tooth devitalization after MSFA is ≤0.7%.

Objectives The aim of this study was to perform a histomorphometric evaluation of the healing characteristics and jawbone remodeling processes in the peri-implant bone tissue of three commonly used implant surfaces, during the early weeks of osseointegration. Material and methods Dental implants with three different surfaces (anodically modified, hydroxyapatite (HA)-coated and machined) were inserted into the mandibular side-tooth region of twelve adult mini-pigs. Histomorphometric analyses were performed to evaluate remodeling processes 3, 6 and 12 weeks post-implantation. Results Only a few very early bone remodeling–resorption sites were found at 3 weeks. After 6 weeks, additional signs of remodeling-related reversal and bone formation were detectable in all three groups, which steadily increased until 12 weeks. At the latter time point, the amount of remodeled bone was significantly higher for the anodized and HA-coated surfaces than for the machined implants. Conclusion The results of this study demonstrate that peri-implant bone remodeling can start as early as 3 weeks after implantation and continues at a substantial level up to 12 weeks. The anodic modification or HA coating of implant surfaces appears to accelerate the conversion of primary regenerated bone into more mature secondary lamellar bone. If this observation is of clinical relevance, it has to be clarified in studies that include longer observational time periods.

To evaluate (i) a possible correlation between the mesio-distal gap width and the alveolar ridge (AR) dimensions in patients missing the maxillary lateral incisor (I2) either due to agenesis or loss and (ii) the possibility of straightforward implant placement based on simulation.The bucco-palatal width, area, and height of the AR at the position of I2, and the mesio-distal gap width between the central incisor and the canine, were assessed in maxillary CT scans of three groups: Patients with (i) agenesis of I2 (TBucco-palatal width and area of the AR at I2 and the adjacent teeth was significantly reduced in TIn patients congenitally missing I2, an increased mesio-distal gap width correlates significantly with reduced edentulous AR dimensions. A mesio-distal gap of6 mm was associated with thin bucco-palatal alveolar ridges, precluding straightforward implant placement in 60-80% of the cases.

Therapeutic decisions in periodontal surgery are based on the accurate diagnosis of the furcation. Clinical probing is the basic diagnostic tool; however, the accuracy of clinical probing to distinguish Class II and Class III furcation defects is unknown. Therefore, this study compares clinical probing diagnoses to those of computed tomography (CT).Seventy-five patients with severe periodontal disease were enrolled in this case series study. A total of 582 furcation sites in molars were assigned for the diagnosis of Class II and Class III furcation defects by clinical probing. Diagnosis based on CT served as a reference.The degree of furcation involvement on clinical findings was confirmed in 57% of the sites, whereas 20% were overestimated and 23% were underestimated compared with the radiologic analysis. Only 32% of Class III furcations in the CT scan were detected clinically. The best correlation of CT scan and clinical probing was found at buccal furcation sites in the mandible, with a κ-coefficient of 0.52, and buccal furcation sites in the maxilla, κ = 0.38. The κ-coefficient was 0.35 for lingual furcations, 0.29 for mesial furcations, and 0.27 for distal furcations, showing weaker correlations.CT scans offer more detailed information on furcation involvement than clinical probing. Especially before surgical treatment, three-dimensional radiographic imaging can be a useful tool to assess the degree of furcation involvement and optimize treatment decisions.

Aim To gain further insights and resolve conflicting results in the literature regarding prevalence, predominant location and morphologic variability of maxillary sinus septa. Material and Methods Electronic and hand searching of English literature identified 33 investigations published from 1995 to 2011. Septa were defined as at least 2–4 mm in height. Results Septa were present in 28.4% of 8923 sinuses investigated (95% confidence interval: 24.3–32.5%). Prevalence was significantly higher in atrophic sinuses compared with dentate maxillae (p

Oral Diseases (2010) 17, 33–44 Objectives: To study the natural aetiopathology of jaw atrophy after tooth loss, unaltered by prosthetic procedures, an historical population without modern dental treatment was examined. Methods: Based on the hypothesis that there are predictable changes in shape during jaw-atrophy, frequency and degree of atrophy as well as clinical aspects of bone quality and resorption were determined in the skeletal remains of 263 individuals. The potential association between age and frequency/severity of atrophy was analysed. Results: Atrophy in at least one jaw segment was present in 45.2% of the analysed jaw specimens. The residual ridge underwent a series of changes in shape and height following the pattern of resorption described for modern populations. The severity of these alterations was associated with the age of the individual and the region within the jaw. Atrophy was frequently related to structural degradation of the covering cortical layer. Conclusions: These findings prove that atrophy of the jaw evidently does occur, displaying similar patterns of resorption in a population without modern prosthetics, where the negative effect of ill-fitting dentures is excluded. The basic information about alterations of shape and the cortical layer covering the residual crest might help to provide a deeper insight into aetiopathological mechanisms of this common oral disease.

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

Objectives: Compared with widespread investigations on dental implant survival and biologic parameters, patient-based outcomes of implant dentistry have been neglected for years and are now becoming more popular. The aim of this representative opinion poll was to assess the up-to-date patients' mindset on dental implants and draw comparisons with the results published in 2003. Material and methods: One thousand adults – representative for the Austrian population – were presented with a total of 16 questionnaire items regarding acceptance and subjectively perceived costs of dental implant treatment as well as patient satisfaction with implant-supported rehabilitation. Results: The implant acceptance rate was 56%, while 23% of the interviewees decidedly rejected implant treatment (same rate as in 2003), especially those over 50 years of age. Only 5% had themselves undergone implant treatment and 22% reported to know someone fitted with implants. The estimated costs of implant treatment were significantly higher than those in 2003, and three-quarters felt that the prize was too high and that the sick fund or social security agencies should bear them. Satisfaction scores were significantly higher among interviewees wearing implant-supported rehabilitations compared with those with conventional fixed or removable dentures. Conclusions: Little has changed in patients' attitude toward dental implants compared with the representative opinion poll in 2003. Neither implant acceptance nor implant prevalence in the Austrian population demonstrated upward trends. Professional public relations efforts are indicated to drop resentments and increase patient acceptance of dental implants as a treatment modality. 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. II: implant acceptance, patient-perceived costs and patient satisfaction. Clin. Oral Impl. Res. 22, 2011; 106–112. doi: 10.1111/j.1600-0501.2010.01969.x

The purpose of this study was to determine the percentage of 'bone area' (BA) and 'bone-to-implant contact' (BIC) of dental implants with different designs and surface modifications after functional loading. Three types of dental implants with fixed partial dentures were placed in the posterior jaws of adult baboons (commercially pure titanium (CpTi) screws, grit-blasted acid-etched (GBAE) screws, and titanium plasma-sprayed (TPS) cylinders), three of the same design per quadrant. After 18 months of functional loading, all implants investigated were successfully integrated in the jawbone and histologic and histomorphometric analyses were carried out. Statistical evaluation was performed with a mixed model with data given as least-square means and standard errors of the mean (SEM). Histologically, direct BIC without connective tissue interposed between implant surfaces and peri-implant bone was seen. Analysis of BA within 1 mm around implants showed significant differences between CpTi (50.5%) and TPS (39.7%) (+/-2.72 SEM; P

Human gingival fibroblasts (GFB) may produce prostaglandin E(2) (PGE(2)) in response to proinflammatory cytokines. Elevated concentrations of glycine were previously found in periodontal pockets and saliva of periodontitis patients and, therefore, we aimed to study the influence of glycine on PGE(2) production.Human GFB were cultured in the presence of various concentrations of glycine and/or interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha, and IL-10 and their influence on PGE(2) production was measured. The expression of cyclooxygenases (COX) was analyzed by Western blot and immunocytochemistry.The PGE(2) production by IL-1beta-stimulated GFB was significantly upregulated by glycine. The effect of glycine on IL- 1beta-induced cell proliferation and PGE(2) production was concentration- dependent, reached a peak at 3 mM, and declined slowly at higher doses. The synthesis of PGE(2) by human GFB cultured in the absence of glycine was significantly inhibited by IL-10 and partially induced in cells cultured with glycine. Glycine had no effect on TNF-alpha-induced PGE(2) production. The IL-1beta-driven PGE(2) synthesis was blocked by indomethacin, a COX-1/COX-2 inhibitor, and by COX-2 inhibitor NS-398. The expression of COX-2 protein was slightly induced by glycine, more evidently by IL-1beta, and mostly enhanced by combined IL-1beta with glycine.Since PGE(2) is a potent stimulator of bone resorption, and production of PGE(2) and COX-2 protein is augmented by glycine, our results strongly suggest that glycine may be involved in the pathogenesis of periodontitis.

Objectives: Soft and hard tissue healing around submerged and nonsubmerged versions of one dental implant design was evaluated in an experimental canine peri-implantitis model. Material and methods: Forty-eight c.p. Ti-implants with integrated (one-piece=OPI) or screw-on (two-piece=TPI) abutments were inserted in edentulous mandibles of eight beagle dogs, one OPI and one TPI with connected abutments for nonsubmerged and one TPI without abutment (SMI) for submerged healing. After 3 months, all implants were functionally loaded, and at 4 months peri-implantitis was ligature-induced in one jaw side. Intravital polyfluorochrome labeling, monthly conventional radiography and gingival probing of all 48 implants were performed until sacrifice 8 months postimplantation. Undecalcified ground sections in the bucco-lingual and mesio-distal planes of four dogs (23 implants, one implant lost) were evaluated by light and fluorescence microscopy. The immunohistochemical and SEM-vascular corrosion cast results of the four other dogs (24 implants) will be reported elsewhere. Levels of alveolar bone-to-implant contact (ABICL), alveolar crest (ACL) and junctional epithelium-to-implant contact were determined by computer-assisted histometry. Peri-implant alveolar bone loss (=saucerization) was assessed on the radiographs and calculated as ACL minus ABICL from histometric data. Results: Around SMIs and OPIs without ligature less plaque adhesion and lower gingival indices were found when compared to TPIs. Radiologically, all ligatured, but also some nonligatured implants showed alveolar bone loss. Histometry demonstrated reduced ABICL around all these implants. Saucerization was more pronounced on the lingual and mesio-distal sides. Particularly around TPIs, bone resorption was still active or bone formation was impaired on fluorochrome labeling. Only around SMIs and one OPI without ligature continuing alveolar bone formation reflected by gains in ABICL were found. Conclusion: The clinical and histometric results of this study demonstrate that healing of submerged SMIs was not impaired by the two-stage procedure, resulting in equally good healing as around nonsubmerged OPIs. However, peri-implantitis plaque-induced by ligature and/or dilated abutment connection microgaps in TPIs affected alveolar bone-to-implant contacts more than transmucosal or submerged healing mechanisms.

Background: In cases of a missing maxillary lateral incisor, an implant-supported crown is often the treatment of choice in order to avoid affecting intact adjacent teeth; however, proper implant p ...

Background Maxillary sinus floor augmentation (MSFA) with autologous bone and/or bone substitutes is a reliable procedure to develop an implant site. Loss of augmentation volume during the healing ...

The maxillary blood supply is essential for preserving the vitality of the affected maxillary region, integration of the grafting material, and wound healing such as following sinus floor elevation. Although it is well established that edentulous maxillae demonstrate a decreasing vascularity as bone resorption progresses, the vascular conditions relevant to sinus floor elevation procedures have not been investigated yet. This study deals with maxillary arteries relevant to sinus floor elevation surgery and examines the vascularization of the lateral maxilla after tooth loss. The vessels of the lateral maxilla of 18 maxillary specimens (10 male, 8 female, mean age 67 years) were prepared anatomically and the local main arteries, the number of macroscopically discernible branches and anastomoses, their calibers, and the distance between the caudal main branches and the alveolar ridge recorded. The lateral maxilla is supplied by branches of the posterior superior alveolar artery (PSAA) and the infraorbital artery (IOA) that form an anastomosis in the bony lateral antral wall, which also supplies the Schneiderian membrane. This intraosseous anastomosis was found in all of the specimens. Eight of 18 also showed an extraosseous anastomosis between PSAA and IOA, vestibular to the antral wall, giving off an average of 3 branches cranially and 5 branches caudally. The two anastomoses form a double arterial arcade to supply the lateral antral wall and, partly, the alveolar process. The PSAA had a mean caliber of 1.6 mm and exhibited an average of 2 endosseous and 1 extraosseous branches. The IOA had a mean diameter of 1.6 mm and showed an average of 1 endosseous and 3 extraosseous branches. The mean distance between the intraosseous anastomosis and the alveolar ridge was 19 mm in 2 defined measuring sites. Its mean length was 44.6 mm. The epiperiosteal vestibular anastomosis was situated further cranially at a mean distance of 23 to 26 mm from the alveolar ridge and had a mean length of 46 mm. The rather large caliber of the vessels supplying the lateral antral wall seems to be crucial to the fact that the periosteal blood supply is maintained even in severe maxillary atrophy and after complete disappearance of the centro-medullary vessels.

Localized periodontal destruction has been reported as a rare complication of intraoral piercings. The purpose of this case report was to illustrate the destructive nature of a lip stud and to describe the successful treatment of this case. The lip stud was removed and supra- and subgingival debridement was performed. Because of a shallow vestibule, the absence of keratinized gingiva, and the strong frenulum insertion at the gingival margins, a free gingival graft was placed. Subsequently the patient demonstrated a significant amount of osseous regeneration and partial coverage of the recession, which has been clinically and radiographically (computed tomography) documented.

Trabecular bone volume and trabecular connectivity (trabecular bone pattern factor) of edentulous mandibles were examined using undecalcified bone sections from the region of the 1st premolar to investigate atrophy-related changes in mandibular cancellous bone. The mean trabecular bone volume was 21.8% in female mandibles and 36.6% in male mandibles. The mean trabecular bone pattern factor was -0.22 mm-1 for female mandibles and -2.29 mm-1 for male mandibles. The difference between the sexes was statistically conspicuous for both parameters, but did not attain statistical significance. A notable fact was the extreme range of variation in both trabecular bone volume and trabecular connectedness. A difference of 65% between the highest and the lowest trabecular bone volumes measured in the present study (min, 7.6%; max, 73.6%, both male) reflects the possible variation in trabecular density of edentulous mandibles.

Recently, sonography of the fetal face has gained increasing importance in prenatal diagnosis. It is not yet clear whether sonographic depiction of fetal tooth germs would have an influence on the prenatal diagnosis of ectodermal dysplasia syndromes. During routine malformation screening, horizontal sections of fetal jaws were visualized and examined for tooth germs in 124 pregnant women following sonographic 'facing'. Histological jaw sections of fetuses that had died in utero at various gestational ages were produced in order to examine the degree of correspondence between the sonographic and histological findings. At least four tooth germs were found in the jaws of all fetuses between 19 and 34 gestational weeks (n = 104). Although jaw visualization was possible between 14 and 18 gestational weeks (n = 20), the exact number and location of the tooth germs could not be determined. Assessment of tooth germs may become increasingly important, as aplasia of the tooth germs is one of the principal signs of various hereditary ectodermal diseases.