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PubMed1981

Histomorphometric study of bone remodeling in hypophosphatemic vitamin D-resistant rickets.

Static and dynamic histomorphometric parameters were evaluated on undecalcified iliac crest bone biopsies obtained from eight children with untreated hypophosphatemic vitamin D resistant rickets (VDRR) in an attempt to evaluate whether a primary metabolic bone defect contributes to the skeletal disorder observed in that disease. When compared to normal age-matched controls the trabecular calcified bone volume was not decreased and there was no evidence of excessive osteoclastic resorption. Both trabecular and cortical bone envelopes had an excess of osteoid tissue and a decreased extent of the mineralization front. Dual tetracycline labeling revealed a decrease in the osteoblastic calcification rate and a marked prolongation of the mineralization lag time and of the formation period. In the intracortical Haversian system the birthrate of new Basic Multicellular remodeling Units (BMU) was markedly reduced, leading to a marked depression of the bone formation rate at the whole tissue level. The combination of the decreased birthrate of new BMU and the prolonged formation period appears to be characteristic of the disease. These results indicate that abnormal differentiation and function of the osteoblast contribute to the osteomalacic lesion present in VDRR. Defective mineralization and impaired osteoblastic function might be the consequence of the chronic hypophosphatemic state. However, the existence of a primary disorder of the bone cell line cannot be excluded as an explanation of the defective recruitment and function of the bone forming cells.

Adolescent↗
PubMed2001

Prediction of strength of cortical bone in vitro by microcomputed tomography.

OBJECTIVE: The aim of this study was to evaluate the predictive value of bone mineral density and intracortical porosity measured by microcomputed tomography for the strength of cortical bone biopsies. DESIGN: Experimental study comparing the predictive value of bone mineral density and of intracortical porosity determined in vitro by microcomputed tomography for the mechanical properties of cortical bone cylinders. BACKGROUND: The assessment of cortical bone strength might be relevant for the prediction of fracture risk or the choice of suitable therapy strategies in orthopaedic surgery. The predictive value of cortical density for the mechanical properties is discussed controversially. The relevance of intracortical porosity measured by histomorphometry has been established, but the predictive value of porosity determined by microcomputed tomography remains to be explored. METHODS: Femoral cortical bone specimens from the mid diaphysis of 24 patients were harvested during total hip replacement procedure at the location, where a diaphyseal hole (diameter 4.5 mm) was drilled in order to reduce the intramedullary pressure. In vitro intracortical porosity and bone mineral density measurements by microcomputed tomography were compared with strength and elastic modulus assessed by a compression test transverse to the Haversian systems of the same specimens. RESULTS: Significant negative correlations were found between porosity measured by microcomputed tomography scans and yield stress, stiffness and elastic modulus (P<0.001), however, the positive correlations between bone mineral density and mechanical parameters were stronger (P<0.0001). The mechanical parameter best predicted by mineral density as well as by porosity was yield stress (r=0.72,P<0.0001;r=-0.64,P<0.001). CONCLUSIONS: Bone mineral density determined by microcomputed tomography imaging in vitro may be a potent method to predict mechanical properties of cortical bone non-destructively. The application in vivo remains to be explored.

Aged↗
PubMed1985

Healing of mandibular ridge augmentations using hydroxylapatite with and without autogenous bone in dogs.

Dog mandibles were augmented with either hydroxylapatite (HA) alone or HA combined with autogenous bone. Within the limited time frame of this experiment (16 weeks) the group which received HA alone did not demonstrate the induction of bony ingrowth further than 1-2 mm into the augmented ridge. However, the animals augmented with HA combined with autogenous bone demonstrated an active, lamellar-type bony ingrowth, maturing bony haversian systems, and vascular elements forming throughout the entire area, extending to the overlying soft tissue interface. The clinical assessment of both types of augmented ridges (HA and HA and bone) were similar; both formed hard, firm ridges at approximately the same rate. This observation is consistent with human clinical experience with HA or HA mixed with bone. However,for patients who have severe mandibular atrophy and for whom increased mandibular bony bulk is crucial, a combination of HA and bone should be advantageous because of the increased extent of bony ingrowth.

Alveolar Ridge Augmentation↗
PubMed2000

Hyperphosphatasemia: report of three cases.

We report the radiographic findings in three cases of hyperphosphatasemia. Often classified as a congenital bone dysplasia, the skeletal manifestations of this disorder are diagnostic. These features simulate Paget's disease both radiographically and with respect to salient biochemical markers. Typically, presentation is at early childhood with skull deformity, refusal to weight bear, and bowing of the extremities. Notable radiographic features include bowing of the long bones, thickening of the cortex, osteopenia, coarsened trabecular pattern, expansion of the medullary cavity, and thickening of the intramembranous portion of the calvarium. Histologic features include absence of lamellar bone and haversian systems, with thick osteoid seams and increased number of osteoclasts. An autosomal recessive pattern of inheritance has been suggested, although autosomal dominant varieties have been postulated.

Adult↗
PubMed2000

Adaptive bone modeling and remodeling in acute otitis media caused by non-typeable or type B Haemophilus influenzae or Moraxella catarrhalis.

Experimental studies have shown that acute otitis media caused by Streptococcus pneumoniae alters modeling dynamics in bone tissue structures surrounding the middle ear cavity. Initial resorption of bone is followed by formative activity, seen as massive osteoneogenesis. However, neither resorptive nor formative activity occurs in the otic capsule, supporting the existence of a perilymphatic zone of specialized bone. This study investigates adaptive bone modeling in acute otitis media caused by other bacteria frequently encountered in this disease. Seventy-five rats were inoculated with either non-typeable or type b Haemophilus influenzae, or Moraxella catarrhalis (25 rats in each group). Five rats from each group were sacrificed on days 4, 8, 16, 60 and 180 post-inoculation. Qualitative as well as quantitative histopathology revealed increasing apposition of new bone on both sides of the original bony wall of the middle ear bulla, i.e. at the inner and outer periosteum. Remodeling activity was seen on later days of sacrifice, as typical osteone (Haversian system) formation. Measured bone thickness in four anatomically well-defined localities progressed to a peak 2 months post-inoculation, followed by some degree of normalization. However, bone thickness was still massively increased 6 months after the acute incident. Except in the otic capsule, resorptive and formative activity was found in all bone tissue structures surrounding the middle ear cavity. These findings were irrespective of the type of inoculated bacteria. However, non-typeable or type b Haemophilus influenzae induces significantly more new bone formation than Moraxella catarrhalis. We conclude that acute otitis media caused by either of the bacteria is accompanied by massive and progressive net osteoneogenesis, already evident on day 4 and peaking 2 months post-inoculation, followed by some degree of normalization. Non-typeable and type b Haemophilus influenzae induce more new bone formation than Moraxella catarrhalis, whereas other features of bone histomorphology were equivalent. The present findings further support the existence of a perilymphatic zone of specialized bone.

Acute Disease↗
PubMed2005

Musculoskeletal responses of 2-year-old Thoroughbred horses to early training. 6. Bone parameters in the third metacarpal and third metatarsal bones.

AIM: To determine the effect of a known training regimen on the size and mineral content of the third metacarpal (Mc3) and third metatarsal (Mt3) bones of 2-year-old Thoroughbred horses trained on racetracks. METHODS: Mc3 and Mt3 of seven horses trained on grass and sand tracks were scanned at several sites using conventional quantitative and peripheral computed tomography (CT). Bone dimensions and density in the diaphysis and epiphysis were compared with those from seven untrained horses. Calcein label was injected in two clusters, during Weeks 9 and 12. The extent and rate of diaphyseal modelling was determined by confocal fluorescent microscopic examination of thin plane parallel sections of the mid-metacarpal region. RESULTS: Volumetric bone mineral density (BMDv) of the epiphysis was markedly higher and of the diaphysis was slightly higher in trained compared with untrained horses, but greater bone size in the trained horses had the greatest effect on an index of bone strength. Active osteons, defined as Haversian systems containing calcein label, were fewer, of smaller diameter at the time of calcein injection, and had a greater bone apposition rate in trained than in untrained horses. CONCLUSIONS: Conventional training of 2-year-old Thoroughbred racehorses over a 13-week period had a significant effect on bone size, density and strength index when compared to untrained horses. CLINICAL RELEVANCE: Bone responded rapidly to early training. The data provide reference values and sites for use in longitudinal studies of commercial training regimens.

Animals↗
PubMed1965

MICROSCOPIC DETERMINATION OF BONE PHOSPHORUS BY QUANTITATIVE AUTORADIOGRAPHY OF NEUTRON-ACTIVATED SECTIONS.

Longitudinal sections of human cortical bone were submitted to thermal neutrons. gamma-ray spectra were recorded repeatedly during 15 days following irradiation. They showed that Na(24) is predominant as early as 3 hours after activation and that all the gamma-emitters have decayed on the 15th day. When the gamma-rays have disappeared, beta-rays are still produced by the sections. It was proved by the absorption curve in aluminium that all these beta-rays are issued from the P(32) induced in the sections by activation of P(31). Therefore autoradiograms registered 15 days after activation reveal the distribution of P(32) in the sections. gamma-ray spectra and beta-ray absorption curves of neutron activated sections of ivory demonstrated a mineral composition similar to that of bone. Autoradiograms of ivory sections activated for various times were used to establish the relation between the optical density of the autoradiograms and the radioactivity in P(32). When the bone autoradiograms are compared with the ivory standards of known radioactivity, the optical densities of single osteons (Haversian systems), can be related to their phosphorus contents. Autoradiograms and microradiograms of the same sections were examined side by side. The least calcified osteons, that contain 80 per cent of the calcium of the fully calcified osteons, also contain about 80 per cent of the phosphorus of the fully mineralized osteons. It is concluded that the Ca:P ratio remains constant while mineralization of bone tissue is being completed.

Activation Analysis↗
PubMed1997

Bone histomorphometry in adults with type IA osteogenesis imperfecta.

A histologic and histomorphometric analysis was performed on undecalcified bone from 8 adult patients, ages 34 to 64 years, with Type IA osteogenesis imperfecta. Complete histomorphometric data, including static and dynamic parameters of bone remodeling, could be generated on 6 patients, and partial data were obtained from the other 2 patients. Findings in some patients of reduced eroded surfaces and reduced osteoid surfaces suggested low bone turnover. Other findings included normal or slightly reduced labeled surfaces, slightly reduced bone formation rate, decreased cortical thickness, and decreased bone volume. Histologic examination results showed lamellar bone with mature cortical Haversian systems. Trabeculae showed qualitatively normal connectedness despite low trabecular volume. The finding of normal or reduced bone turnover in adults with Type IA osteogenesis imperfecta has not been reported. Earlier histomorphometric studies, performed without correlation with a specific age or phenotype, indicated high bone turnover. The present study suggests that future research should correlate histopathologic changes with specific phenotypes. The finding of normal or slightly reduced bone turnover in Type IA osteogenesis imperfecta may have important therapeutic implications for this phenotype.

Adult↗
PubMed2002

A 1-year study of osteoinduction in hydroxyapatite-derived biomaterials in an adult sheep model: part I.

The study presented here investigated hydroxyapatite biomaterials implanted in soft-tissue sites in adult sheep to determine whether these materials are osteoinductive and whether the rate of osteoinduction can be increased by manipulating the composition and porosity of the implants. For the study, 16.8-mm x 5-mm discs were prepared from mixtures of hydroxyapatite and beta-tricalcium phosphate. Five mixtures of hydroxyapatite-ceramic and hydroxyapatite-cement paste forms were studied: 100 percent hydroxyapatite-ceramic (Interpore), 60 percent hydroxyapatite-ceramic, 100 percent hydroxyapatite-cement paste, 60 percent hydroxyapatite-cement paste, and 20 percent hydroxyapatite-cement paste. Biomaterials were implanted in subcutaneous and intramuscular soft-tissue pockets in 10 adult sheep. Cranial bone grafts of equal dimension were implanted as controls. One year after implantation, the volume of all biomaterials and bone grafts was determined from a computed tomographic scan, and porosity and bone formation were determined using backscatter electron microscopy. Cranial bone and the 20 percent hydroxyapatite-cement paste implants demonstrated significant volume reduction in all sites after 1 year (p < 0.001). No significant difference in volume of the remaining four biomaterials was found. There was no significant change in pore size in the ceramic implants (range, 200 to 300 micro) and in the cement-paste implants containing 60 percent hydroxyapatite or more (range, 3 to 5 nm). Pore size in the cement-paste implants containing 20 percent hydroxyapatite increased significantly with resorption of the tricalcium-phosphate component, reaching a maximum of 200 to 300 micro in the periphery, where the greatest tricalcium-phosphate resorption had occurred. Both ceramic biomaterials demonstrated lamellar bone deposition within well-formed haversian systems through the entire depth of the implants, ranging from a mean of 6.6 percent to 11.7 percent. There was minimal bone formation in the cement-paste implants containing 60 percent hydroxyapatite or more. In contrast, cement-paste implants containing 20 percent hydroxyapatite demonstrated up to 10 percent bone replacement, which was greatest in the periphery of the implants where the greatest tricalcium-phosphate resorption had occurred. This study confirms the occurrence of true osteoinduction within hydroxyapatite-derived biomaterials, when examined using backscatter techniques. In this study, the rate of osteoinduction was greatest when a porous architecture was maintained, which was best achieved in ceramic rather than cement-paste forms of hydroxyapatite. Porosity and resultant bone formation in cement-paste implants can be improved by combining hydroxyapatite with a rapidly resorbing component, such as tricalcium phosphate.

Animals↗
PubMed2006

Histologic evaluation of 3 retrieved immediately loaded implants after a 4-month period.

OBJECTIVE: To perform a histologic and histomorphometric analysis of the peri-implant tissue reactions and bone-titanium interface in 3 immediately loaded (provisional loaded) titanium implants retrieved from a man after a loading period of 4 months. MATERIALS & METHODS: A 35-year-old patient with a maxillary partial edentulism did not want to wear a provisional removable prosthesis during the healing period. It was decided to insert 3 definitive implants and use 3 provisional implants for the transitional period. The provisional implants were loaded the same day with a resin prosthesis in occlusal contact. During the second surgical phase, after 4 months, the provisional prosthesis was removed, and the provisional implants were retrieved with a trephine bur. Before retrieval, all implants appeared to be clinically osseointegrated. The specimens were processed for observation under light microscopy. RESULTS: At low magnification, it was possible to observe that bone trabeculae were present around the implant. Areas of bone remodeling and haversian systems were present near the implant surface. Under polarized-light microscopy, it was possible to observe that in the coronal aspect of the thread, the lamellar bone showed lamellae that tended to run parallel to the implant surface, while in the inferior aspect of the thread, the bone lamellae ran perpendicular to the implant surface. CONCLUSIONS: Histologic data pertaining to these 3 immediately loaded implants, and retrieved after a 4-month loading period, show that immediate loading did not produce untoward effects on peri-implant bone healing.

Adult↗
PubMed1976

Changes in shape, ossification and quality of bones in children with spina bifida.

Changes in the cross-sectional shape, size, bone mass and amount of unmineralised osteoid tissue were studied in 17 dissected tibiae from spina-bifida babies who died with paralysis and foot deformities and in 14 tibiae from non-spina bifida controls of matching age. In addition, 12 tibiae from young experimental rats with myotomy of foot dorsiflexors and foot plantiflexors were double-labelled with bone-seeking markers and studied in order to find the role of experimental muscle imbalance in the dynamic remodelling of the developing long bones. It was found that in tibiae from spina-bifida children with paralysis the total area of cortical bone, its thickness, number of Haversian systems and number of large remodelling cavities are diminished. Significant changes in the cross-sectional shape of the midshaft of the tibia were found, ranging from the triangular shape seen in normal babies and in those with spina bifida and calcaneus-type foot deformity, to the circular shape of tibiae from babies with spina-bifida paralysis and no foot deformity or with spina bifida and equinovarus-type of deformity. Results of experimental myotomy on growing rats showed the direct influence of working muscles on the remodelling process of growing tibiae. On the side of myotomy the flat cortex resumed a bulging convex shape and the centre of gravity shifted towards the myotomised side. These principles cannot on their own explain the specific changes in the shape of human tibiae found during anatomical studies. There is, however, a common denominator in these apparently contradictory findings. This is the combined action of two factors previously reported: the combination of paralysis of the growing limb and mechanical intra-uterine pressure acting on it. The findings in the present study also indicate that they played a major role in the production of deformities. The total amount of osteoid tissue in spina-bifida paralysed bone is increased. This delay of mineralisation of newly laid-down bone matrix would lead to softening of the new bone matrix and osteoid-rich subepiphyseal and metaphyseal regions. This 'paralytic rickets', together with the diminished total bone mass found, could probably be the cause of the common spina-bifida fractures in these regions.

Animals↗
PubMed1996

Radicular cysts are involved in the recruitment of osteoclast precursors.

In consideration of the close relationship between radicular cysts and alveolar bone, it is important to evaluate the potential involvement of the neighbouring bone tissue in such lesions. In the present study, using cytochemical, immunocytochemical and morphological analyses, presumptive osteoclast precursors were revealed in the connective tissue of radicular cyst capsules. The osteoclastic nature of these cells was postulated by their positive staining for the enzyme tartrate-resistant acid phosphatase (TRAP) and by the expression of vitronectin receptor (VnR) on their cell surface. However, these cells did not express the vacuolar-type proton pump, suggesting that they may represent early osteoclast precursors infiltrating the cyst capsule. Cysts also contained activated small blood vessels whose endothelial cells expressed the VnR. This integrin receptor is important in the adhesion of preosteoclasts to the endothelial lining, a necessary step for their emigration out of the vasculature. Therefore, the intracystic vessels could represent a substrate for preosteoclast recruitment. These precursor cells may then reach the perialveolar bone surface and contribute to bone demolition together with those recruited by the resorbing surfaces. The bone-destroying potential of radicular cysts was confirmed by the presence of numerous osteoclasts with large resorption areas on the perialveolar bone surfaces exposed to the cyst capsules. The resorbed surfaces were usually located around the vascular canals of the Haversian systems.

Acid Phosphatase↗
PubMed1990

The clinical features of three babies with osteogenesis imperfecta resulting from the substitution of glycine by arginine in the pro alpha 1(I) chain of type I procollagen.

The features of three babies with lethal perinatal osteogenesis imperfecta resulting from the substitution of glycine by arginine in the pro alpha 1(I) chain of type I procollagen were studied. The babies were heterozygous for this substitution at residue 391 in case 1 (0I24), 667 in case 2 (0I51), and 976 in case 3 (0I30). They were all small, term babies who died soon after birth. The ribs were broad and continuously beaded in 0I24, discontinuously beaded in 0I51, and slender with few fractures in 0I30. The overall radiographical classifications were type IIA in 0I24, IIA/IIB in 0I51, and IIB in 0I30. Histological examination confirmed that the long bones were misshapen and porotic. The calcified cartilage trabeculae were covered with an abnormally thin layer of osteoid and the bone trabeculae were thin and basophilic. There was no evidence of lamellar bone or Haversian systems. The osteoblasts remained relatively large and closely spaced. These babies shared many phenotypic features, but differences in the radiographical appearance of the ribs and long bones suggested that there was a gradient of bone modelling capacity from the slender and overmodelled bones in 0I30 to the absence of modelling in 0I24.

Female↗
PubMed1994

The clinical features of Ehlers-Danlos syndrome type VIIB resulting from a base substitution at the splice acceptor site of intron 5 of the COL1A2 gene.

The features of a 32 year old woman with Ehlers-Danlos syndrome type VIIB and affected members of her family, resulting from a mutation in one COL1A2 allele, were studied. Her dermal type I collagen contained alpha 2(I) chains and mutant pN-alpha 2(I) chains in which the amino-terminal propeptide remained attached to the alpha 2(I) chain. She was heterozygous for an AG-->AC mutation at the splice acceptor site of intron 5 of the COL1A2 gene. The mutation activated a cryptic AG splice acceptor site corresponding to positions +14 and +15 of exon 6 of the COL1A2 gene. In contrast to previous reports only five, rather than all 18, amino acids encoded by exon 6 were deleted in the proband. The deleted peptide removed the amino-proteinase cleavage site, but not the nearby lysine cross linking site in the amino-telopeptide of the alpha 2(I) chain. She was born with bilateral hip dislocations, knee subluxations, and generalised joint hypermobility. Bilateral inguinal herniae and an umbilical hernia were present at birth. Facial features included a depressed nasal bridge with prominent paranasal folds. The skin was soft, moderately hyperelastic, and sagged over the face. Skin fragility and easy bruising were apparent from childhood. Skin wounds healed slowly and with broad, paper thin scars. Throughout her life, she had multiple fractures of the small bones of her hands and feet following moderate trauma. Electron microscopy of the proband's dermis as well as deep fascia and hip joint capsule from her affected brother showed that collagen fibrils in transverse section were nearly circular but with irregular margins. Light microscopy of bone from her affected brother and son showed normal Haversian systems and lamellar bone. All of these tissues contained approximately equal amounts of the normal and mutant alpha2(I) chains. The findings of this study confirm that loss of the amino-proteinase cleavage site of the pro alpha2(I) collagen chains, owing to anomalous splicing of exon 6 sequences in the conversion of pre-mRNA to mRNA, produces the clinical features of Ehlers-Danlos syndrome type VIIB. The history of frequent fractures found in this family is atypical and indicates an overlap with osteogenesis imperfecta.

Adult↗
PubMed1996

Disrupted growth plates and progressive deformities in osteogenesis imperfecta as a result of the substitution of glycine 585 by valine in the alpha 2 (I) chain of type I collagen.

The skeleton of a child with osteogenesis imperfecta type III, resulting from the substitution of glycine 586 by valine in the triple helical domain of the alpha 2 (I) chain of type I collagen, was severely porotic but contained lamellar bone and Haversian systems. From early childhood, structural failure of the bone resulted in the disruption of growth plates, progressive bone deformities, and severe growth retardation.

Adolescent↗
PubMed1996

Arachnoid cyst and chronic subdural haematoma in a child with osteogenesis imperfecta type III resulting from the substitution of glycine 1006 by alanine in the pro alpha 2(I) chain of type I procollagen.

The features of a child with osteogenesis imperfecta type III (OI III) resulting from the heterozygous substitution of glycine 1006 by alanine in the pro alpha 2(I) chain of type I procollagen were studied. He was born at term with the clinical features of severe OI, including deep grey-blue sclerae. He had severe osteopenia and all long bones were smaller than normal with cortical thinning, metaphyseal expansion, poor metaphyseal modelling, and multiple fractures. However, the vertebrae, pelvis, and shoulder girdle were of normal shape and there were few rib fractures. Histological examination of the calvarium and tibial shaft showed woven bone without lamellar bone or Haversian systems. The shafts of the long bones were widened owing to repeated fractures. Progressive enlargement of the calvarium occurred between 3 and 4.5 months of age owing to bilateral chronic subdural haematomata and a large arachnoid cyst in the Sylvian fissure. The cyst was probably developmental in origin while the subdural collections were probably the result of perinatal skull trauma. The cyst and the subdural collections resolved following drainage but ventricular dilatation with normal cerebrospinal fluid pressure followed. The proband is the first reported case of OI with a glycine substitution by alanine in the pro alpha 2(I) chain of type I procollagen.

Adult↗
PubMed1981

Intracortical fissuring in osteomyelitis.

Cortical fissuring, a well-recognized radiographic sign of osteomyelitis, represents spread of infection through the haversian system with osteoclastic bone resorption. In the proper clinical setting this finding may be recognized before there is other evidence of bone destruction or periosteal reaction. Three cases are presented that illustrate the sign at a relatively early stage in the progress of the osteomyelitis. While fissuring was previously considered evidence of sickle cell anemia, only one of our patients had sickle hemoglobin.

Adult↗
PubMedDate not supplied

Microradiographic study of retrieved craniofacial osseointegrated implants.

In this study 18 screw-shaped extraoral osseointegrated implants retrieved from 10 patients were analyzed. The reasons for retrieval were: unexplained pain (n = 4); inability to cope with the implants (n = 2); fracture of the central screw (n = 2); skin penetration problems (n = 1), and trauma (n = 1). Retrieved implants were trephined with a border of surrounding bone, fixed, embedded in epon plastic, ground and processed for microradiography. The study group comprised 6 males and 4 females with a mean age of 53.4 (range 9-81) years. All implants were clinically stable at the time of removal, and the mean osseointegration time was 3 (range 1-5) years. Six implants were removed from the temporal bone, 5 from the frontal bone, and 7 from the maxilla. By microradiography, it was found that all retrieved implants were surrounded by a lamellar type of bone with haversian systems, vascular channels, osteocyte lacunae, and in some specimens regeneration and resorption areas. Bone metal contact was estimated to vary between 27 and 83%. Bone metal contact was lower in the frontal bone compared to the temporal bone or maxilla, and was further reduced after preoperative irradiation. Longer osseointegration time increased bone metal contact, as did increased age up to 60 years. It is concluded that extraoral osseointegrated implants in humans may integrate morphologically as well as clinically. By microradiography it was possible to define bone metal contact in the region of implant installation.

Adult↗