Periradicular healing in response to Diaket root-end filling material with and without tricalcium phosphate

The healing of the periradicular tissues was evaluated when the polyvinyl resin Diaket with and without tricalcium phosphate was used as surgical root-end filling material. Non-surgical root canal treatment was performed on 56 mandibular premolar roots in mongrel dogs. Following root-end resection, root-end cavity preparations were filled with Diaket, the comparative material, or Diaket in combination with tricalcium phosphate, the experimental material. Postsurgically, healing of the tissues adjacent to the filling materials and in the surrounding surgical site were evaluated at 30 and 60 days. There was virtually no statistically significant difference between the experimental and comparative group at or within the 30- or 60-day period with regard to inflammation, connective tissue formation, root-end encapsulation, cementum formation, or bone apposition. Findings suggest that cementogenesis occurred over both materials. The overall healing of the periradicular tissues was favourable.     

The effect of transforming growth factor beta one (TGF-beta 1) on wound healing, with or without barrier membranes, in a Class II furcation defect in sheep

The purpose of this study was to analyse the effect of TFG-beta 1 on wound healing in standardized Class II furcation defects of 48 mandibular second premolar teeth in 24 sheep. The experimental design included a control group (carrier only, 25% pluronic F-127), and 2 experimental groups: group A (80 micrograms/ml TGF-beta 1 + carrier) and group B (80 micrograms/ml TGF-beta 1 + carrier covered with a barrier membrane). Sheep were killed either 2 wk or 6 wk after surgery. Mesiodistal sections of the decalcified specimens were quantified histologically using stereology. Percentage volumes of regenerated bone, fibrous connective tissue and cementum were calculated for each furcation defect. Mean values were analysed using multiple ANOVA; p values were calculated using paired and unpaired Student's t-tests. After 2 wk there was more bone in group B than either of the other 2 groups, but this was not statistically significant. By 6 wk more bone was present in group A than in the control group (p < 0.02) and also in group B when compared with both group A and the control group (p < 0.02 and p < 0.44), respectively. In the 4 wk between sampling significantly more bone had formed (group A < 0.05 and group B p < 0.003, respectively). A negative correlation existed between volumes of bone and fibrous connective tissue and no significant differences between the volumes of cementum were evident between any of the groups. This study demonstrated that TGF-beta 1 encouraged bone regeneration in Class II furcation defects in sheep, an effect enhanced by the presence of a barrier membrane. This is the first report on the use of TGF-beta 1 in conjunction with GTR in periodontal defects.     

Induction of reparative dentine formation in monkeys by recombinant human osteogenic protein-1

Osteogenic protein-1 (OP-1, BMP-7), a member of the transforming growth factor-beta supergene family, induces cartilage and bone formation when implanted in intra- and extraskeletal sites in vivo. The human OP-1 gene has been cloned and biologically active recombinant OP-1 homodimers (hOP-1) produced. The amount of bone induced by hOP-1 in vivo is related to the amount of protein implanted. Dentine possesses bone morphogenetic protein (BMP) activity. Impure material from allogenic bone with BMP activity induced reparative dentine formation in dogs. The objective of this study was to determine if the amount of reparative dentine stimulated by hOP-1 is related to the amount of protein utilized in direct pulp-capping experiments. Freshly exposed molar and premolar pulps were treated with varying amounts of a complex comprising hOP-1 and a carrier matrix of purified bovine type-1 collagen powder (CM) moistened with sterile saline. Reparative dentine was present in all hOP-1/CM treated teeth (12 of 15) that remained sealed for the 6 weeks' healing. Substantially more new dentine was present in teeth treated with hOP-1/CM than in those treated with Ca(OH)2 paste and the amount of reparative dentine formed was proportional to the amount of hOP-1/CM (P < 0.05). No reparative dentine formed in collagen carrier or untreated teeth. The appearances of the new tissue suggested that much of the mass of the hOP-1/CM was replaced first by a pulp-like connective tissue, which mineralized to form reparative dentine.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of cementum-impregnated gelatine membrane on early healing following periodontal flap surgery

The purpose of this study was to investigate the initial healing response of surgically flapped periodontal tissues in the presence of gelatine membrane compounded with particles of cementum. Four monkeys with no periodontal disease were used in this experiment. Full thickness flaps were raised and recession type defects were created on the buccal side of the maxillary lateral incisors and second premolars. Exposed root surfaces were thoroughly curetted, and composite cementum-impregnated membranes placed directly onto planed root surfaces. Flaps were then sutured back to the original position. Animals were sacrificed at 2, 4, 7 and 10 post-surgical days, and block specimens including the tooth, gingiva and bone were subsequently processed for light and electron microscopy. The resultant analysis revealed that gelatine membranes were partially resorbed at 2 days post-surgery and completely resorbed by 10 postoperative days. In the early stages of gelatine resorption, most liberated cementum particles accumulated on planed dentin surface but some became demineralized within the surgical wound. Cementoblast-like cells with well-developed rough endoplasmic reticulum appeared on the root surface 7 days following surgery. Newly synthesized collagen fibrils aligned parallel to the root surface were seen at 10 post-surgical days. The results suggest that the newly developed composite membrane enhances the formation of new periodontal attachment.     

Characterization of mechanisms of interleukin-6 gene repression by estrogen receptor

Some prior reports have suggested that guided tissue regeneration (GTR) procedures achieve only partial regeneration and induces the ankylosis rather than true attachment. Accordingly, others have developed an alternative procedure employing gelatine membrane compounded with bovine cementum particles (CGM) which has proven effective in stimulating a more physiologic form of attachment. This study was undertaken to perform a direct comparison of histological results when CGM and GTR membrane were used at comparable sites in the same monkey. Three monkeys with no periodontal disease were used. Following flap surgery, recession type defects were created on the buccal side of the maxillary lateral incisors and second premolars, and the cementum was removed from the root surface at an area corresponding to the bone crest. The right and left lateral incisors and second premolars were covered with CGM and GTR membrane, respectively. The GTR membranes were removed after 4 weeks. At 6 wks, the animals were sacrificed, and specimens were prepared for histological examination. More coronally placed true new attachment was observed following application of CGM to the planed root surfaces. Application of the GTR membrane resulted in formation of bone-like cementum and ankylosis, whereas CGM established true periodontal regeneration.     

Recombinant human osteogenic protein-1 induces dentin formation: an experimental study in miniature swine

It was the aim of the present study to investigate the induction of dentin formation by recombinant human osteogenic protein-1 (hOP-1). In 4 adult miniature pigs a total of 16 teeth with artificially exposed dental pulps were capped with 3 mg of a complex of recombinant hOP-1 in collagen matrix (2.5 micrograms/mg), collagen matrix alone, or calcium hydroxide paste. Teeth were removed in block section after a healing period of 5 weeks. Decalcified sections were processed for light microscopy and histomorphometric analysis. In hOP-1 treated teeth substantial amounts of hard tissue formation (osteodentin and tubular dentin) had consistently led to a complete bridging of the defects. Less dentin formation was seen after calcium hydroxide application. In control defects collagen matrix alone failed to form complete dentin bridges. Recombinant human osteogenic protein-1 in a collagen carrier matrix appeared to be suitable as a bio-active capping agent for surgically exposed dental pulps.     

Neurodevelopmental outcome in very low birth weight infants at 24 months and 5 to 7 years of age: changing diagnosis

The purpose of this study was to evaluate the importance of root canal therapy in the healing process of severe intrabony defects. Four beagle dogs were used and 32 interproximal intrabony defects, up to the apical third, were created. Wire ligatures were placed into these defects for plaque accumulation. Three weeks later, the ligatures were removed and 4 different treatment modalities were employed: group 1) scaling and root planing (SRP); group 2) modified Widman flap (MWF); group 3) modified Widman flap and root canal therapy performed at the same time (RCT/MWF); and group 4) modified Widman flap and root canal therapy performed 3 weeks after the surgical procedure (MWF + RCT). Postoperative oral hygiene was obtained by spraying a 0.12% chlorhexidine solution 3 times a week. The animals were sacrificed 7 weeks after treatment. Blocks were obtained and processed for routine histology. Results were expressed as a percentage of the total defect length (TDL). No differences were observed when SRP was compared to MWF. New bone formation (BF) presented better results for SRP (43.4%) and MWF (53.4%) when compared to RCT/MWF (15.5%). New cementum formation (CF) presented better results for SRP (59.8%) and MWF (64.6%) when compared to RCT/MWF (19.3%) and MWF + RCT (31.5%). Connective tissue repair (CTR) presented better results for SRP (72.4%) and MWF (74.2%) when compared to RCT/MWF (47.5%) and MWF + RCT (44.4%). Results were statistically significant at the level of 0.05. Within the limits of this study, it was concluded that root canal therapy performed simultaneously or 3 weeks after surgery modified the healing of intrabony defects, impairing new bone formation, new cementum formation and new attachment.     

Utstein style cardiopulmonary-cerebral resuscitation registry for out-of-hospital cardiac arrests between 1991 and 1993. The Belgian CPCR Study Group

The authors compared the use of the power saw with bone-cutting forceps for excision of bone. A total of 44 digits were studied in 12 patients. The study was performed on patients requiring bilateral digital arthroplasties of the proximal and distal interphalangeal joints. The authors examined the differences in healing: pain, inflammation, and fibrosis. Digits on which the power cuts were made showed a slight advantage with regard to inflammation and pain, until 1 week after surgery. By week 12, neither technique demonstrated superiority. Overall results demonstrated no significant digit (p > 0.2) or treatment effect (p = 0.11). The authors believe that the study showed that the technique used for bone excision may have little effect on inflammation and healing in the long-term management of a surgical patient.     

Biosensor development

OBJECTIVES: This study compared the surface topography of roots resected with #57, Lindeman, and Multi-purpose burs. Further comparisons were made after refinements with either a multifluted carbide or an ultrafine diamond finishing bur. STUDY DESIGN: Three groups of single-rooted human teeth were resected with each resection bur, and resin replicas of the root ends were made. Root ends from each resection bur group were finished with either a multifluted carbide or an ultrafine diamond finishing bur, and the root ends were replicated. All replicas were evaluated at a magnification of x20 for smoothness and surface irregularities. Data analysis was done with the Wilcoxon signed rank test and the chi-square test at a significance level of p < 0.05. RESULTS: The Multi-purpose bur produced a smoother and more uniplanar surface than the #57 bur and caused less damage to the root than either the #57 or the Lindeman bur. The multifluted carbide finishing bur tended to improve the smoothness of the root end, while the ultrafine diamond tended to roughen the surface. CONCLUSIONS: The Multi-purpose bur produced the smoothest and most uniplanar resected root-end surface with the least root shattering. The multifluted carbide finishing bur produced a smoother surface than the ultrafine diamond bur.     

Effect of allogenic freeze-dried demineralized bone matrix on guided tissue regeneration in dogs

This randomized, split-mouth study was designed to evaluate the adjunctive effect of allogenic, freeze-dried, demineralized bone matrix (DBM) to guided tissue regeneration (GTR). Contralateral fenestration defects (6 x 4 mm) were created 6 mm apical to the buccal alveolar crest on maxillary canine teeth in 6 beagle dogs. DBM was implanted into one randomly selected fenestration defect. Expanded polytetrafluoroethylene (ePTFE) membranes were used to provide bilateral GTR. Tissue blocks including defects with overlying membranes and soft tissues were harvested following a four-week healing interval and prepared for histometric analysis. Differences between GTR+DBM and GTR defects were evaluated using a paired t-test (N = 6). DBM was discernible in all GTR+DBM defects with limited, if any, evidence of bone metabolic activity. Rather, the DBM particles appeared solidified within a dense connective tissue matrix, often in close contact to the instrumented root. There were no statistically significant differences between the GTR+DBM versus the GTR condition for any histometric parameter examined. Fenestration defect height averaged 3.7+/-0.3 and 3.9+/-0.3 mm, total bone regeneration 0.8+/-0.6 and 1.5+/-0.8 mm, and total cementum regeneration 2.0+/-1.3 and 1.6+/-1.7 mm for GTR+DBM and GTR defects, respectively. The histologic and histometric observations, in concert, suggest that allogenic freeze-dried DBM has no adjunctive effect to GTR in periodontal fenestration defects over a four-week healing interval. The critical findings were 1) the DBM particles remained, embedded in dense connective tissue without evidence of bone metabolic activity; and 2) limited and similar amounts of bone and cementum regeneration were observed for both the GTR+DBM and GTR defects.     

Resorbable versus nonresorbable membranes in combination with Bio-Oss for guided bone regeneration

The purpose of this clinical investigation was to compare the new resorbable collagen membrane, Bio-Gide, to the conventional expanded polytetrafluoroethylene material (Gore-Tex) for guided bone regeneration in situations involving exposed implant surfaces. Over a 2-year period, 25 split-mouth patients were treated randomly: one defect site was treated with Bio-Gide and the other defect site with Gore-Tex; all 84 defects were filled with Bio-Oss and covered with the respective membrane. The defect types, their dimensions, and their morphology were measured in detail initially and at re-entry to allow for calculation of the exposed implant surface. Changes in defect surface for both types of membranes were statistically significant (P < .0001); however, no statistical significance (P > .94) could be detected between the two membranes. The mean average percentage of bone fill was 92% for Bio-Gide and 78% for Gore-Tex sites. In the latter group, 44% wound dehiscences and/or premature membrane removal occurred. The resorbable membrane, Bio-Gide, in combination with a bone graft, can be a useful alternative to the well-established expanded polytetrafluoroethylene membranes.     

Nature and attachment of cementum formed under guided conditions in human teeth. An electron microscopic study

In an attempt at characterizing the nature and attachment of cementum formed under conditions of guided tissue regeneration (GTR) in humans, front teeth from 4 patients aged 42 to 72 years were examined at the electron microscopic level. All teeth were affected by complex periodontitis associated with advanced loss of periodontal support. Roots were surgically planed and notched, but not chemically conditioned. Either the mesial or distal surface of each tooth represented the experimental site and was covered with a biodegradable polyglactin 910 barrier, while the opposite approximal surface served as control. Following 3 months of healing, teeth were removed together with surrounding periodontal tissues including some alveolar bone. These blocks were fixed histologically, decalcified, embedded in epoxy, and sectioned for examination in the scanning (backscatter mode) and transmission electron microscope. Both experimental and control sites disclosed 2 types of regenerative cementum that seemed to be formed by cells resembling cementoblasts. The first type was characterized by a thin fringe of collagen fibrils which were arranged perpendicular to the root surface and appeared mineralized in a zone extending about 1 to 3 microm from the dentin. The second type occurred as thick patches which revealed scattered cementocytes and sheets of collagen fibrils oriented mainly parallel to the root surface, running both circularly and axially. In both situations, a continuous, thin, electrondense layer was interposed between newly formed cementum and preexisting radicular hard tissues. Interdigitation of collagen fibrils from cementum and dentin, such as observed along the natural cemento-dentinal junction, did not occur. Thus, regenerative cementum laid down in humans under guided conditions on previously diseased and planed, but not otherwise treated root surfaces shares some morphologic features with cementum formed during spontaneous repair of root resorptions. However, unlike in the course of such repair, a fibrous attachment of new cementum resembling the natural cemento-dentinal junction does not seem to be regenerated under guided conditions.     

IL-1 in gingival crevicular fluid following closed root planing and papillary flap debridement

Interleukin (IL)-1 alpha and beta are cytokines which can mediate inflammatory, bone resorbing, and reparative effects in the periodontium, but few longitudinal data exist exploring their role following periodontal therapy. This study examined gingival crevicular fluid (GCF) concentrations of IL-1 alpha and IL-1 beta at sites with shallow sulci (SS) or inflamed moderate/advanced pockets (M/AP) before and 6 months after treatment with closed scaling/root planing (SC/RP) or papillary flap debridement (PFD), all in the same subject (n = 14 patients). No significant differences were noted in IL-1 alpha or beta concentrations (determined with two-site enzyme-linked immunosorbent assays) between SS and M/AP sites at baseline. While both therapies improved clinical parameters of periodontal disease, IL-1 alpha concentration increased significantly (p < 0.05) in M/AP-PFD sites 6 months after treatment, but were unchanged in other groups. IL-1 beta concentrations were numerically lower after therapy, except for a significant increase (p < 0.05) in M/AP-PFD sites. These data suggest that surgical wound healing in an inflamed, plaque-infected site (M/AP-PFD) results in prolonged production of IL-1, which may be a reflection of the extent of tissue trauma and delayed wound healing. In spite of increased IL-1 levels, these sites demonstrated significant short-term improvement in clinical attachment level (+ 1.8 mm, p < or = 0.001) postoperatively.     

Regeneration of diaphyseal bone defects using resorbable poly(L/DL-lactide) and poly(D-lactide) membranes in the Yucatan pig model

OBJECTIVES: To determine the effects of tubular resorbable polymer membranes on the healing of a segmental diaphyseal bone defect. DESIGN: A randomized prospective study using the minipig model. Animals were evaluated with in vivo roentgenograms on a biweekly basis until explanted at twelve weeks. SETTING: After surgery, animals were allowed unrestricted activity and weight bearing between twenty-four and forty-eight hours. ANIMALS: Fifteen yearling Yucatan minipigs. INTERVENTION: A 2.5- to 3.0-centimeter mid-diaphyseal defect was created in the middle third of the radius. Animals were assigned in groups of three to receive the following implants: (a) poly(L/DL-lactide), (b) poly(L/DL-lactide)-CaCO3, (c) poly(D-lactide), (d) poly(D-lactide)-CaCO3, and (e) an untreated defect. No adjunctive internal or external fixation was used as the ulna was left intact. MAIN OUTCOME MEASURES: The limbs were studied with in vivo anterior-posterior and lateral radiographs at biweekly intervals for the presence and pattern of bone formation. All limbs were explanted at twelve weeks postimplantation for methyl-methacrylate embedding and histologic and microradiographic study. RESULTS: The bone defects covered with membranes were completely reconstituted by six to eight weeks. Untreated defects healed with less bone formation and in a more disorganized pattern. Histologic evaluation of the implants demonstrated that the entire lumen of the implant was filled with bone, with some periosteal bone formation occurring on the outer surface of the membrane. There was direct apposition of bone onto the membrane surface or minimal fibrous tissue interposition between membrane and new bone. There was no foreign body or adverse reaction to the membrane. Untreated defects showed woven bone formation with clefts and irregularly shaped margins occupied by fibrous tissues or surrounding muscle tissues. CONCLUSIONS: This study supports the concept that a membrane enhances bone defect healing by excluding nonosseous tissues from a defect and providing structural scaffolding for periosteal and endosteal bone regeneration.     

Short-term tissue response to potential root-end filling materials in infected root canals

The short-term tissue responses to two potential root-end filling materials, a light-cured glass ionomer cement (Vitrebond) and a reinforced zinc oxide-eugenol cement (Kalzinol), were compared with that to amalgam using a previously devised experimental model. In 24 premolar teeth of beagle dogs (47 roots), a collection of endodontic pathogenic bacteria was first inoculated into the root canals to induce periradicular lesions. On each root, an apicoectomy was performed and root-end cavities prepared to receive fillings of each material. The teeth and surrounding jaw were removed after 2 weeks (23 roots) and 1 week (24 roots); they were then prepared for histological examination. The tissue response to amalgam fillings after 2 weeks and 1 week was marked by moderate or severe inflammation on all roots, and extended to < or = 0.5 mm or > 0.5 mm in 15 out of 16 roots. In contrast, after 2 weeks, the majority of roots filled with Kalzinol showed little or moderate inflammation, while the tissue response to Vitrebond was the best of the three materials, and was also the least extensive. After 1 week, the overall best tissue response was with Vitrebond, followed by Kalzinol. The differences between materials for both time periods with either none or few inflammatory cells when compared with that with either moderate or severe inflammation were not statistically significant (P < 0.02). However, the differences between materials for both time periods with no inflammation or inflammation extending < 0.2 mm when compared with that with inflammation extending > 0.2 mm (< or = 0.5 mm or > 0.5 mm) were statistically significant (P < 0.01). Apart from amalgam, in which healing was marked by the persistence of a localized focus of inflammation adjacent to the root-end filling, even though there were intersample variations, there was little overall difference in the temporal and qualitative healing response to Vitrebond and Kalzinol. Both Vitrebond and Kalzinol have potential as root-end filling materials, as the tissue response was considerably more favourable than that to amalgam even in the short-term.     

Human monocyte response to cementum extracts from periodontally diseased teeth: effect of conditioning with tetracycline

Monocyte inflammatory cytokines, such as TNF alpha and IL-1 beta, have been implicated in the pathogenesis of periodontal destruction. The present study was designed to test the ability of extracts of cementum from periodontally diseased teeth to induce the secretion of these mediators by monocytes, to evaluate the role of adsorbed endotoxin in this process, and to test the effect of cementum conditioning with tetracycline on the monocyte response. Human monocytes were incubated with varying concentrations of cementum extracts, and TNF alpha and IL-1 beta levels in the media were measured. The results showed that while extracts of healthy cementum had no effect on monocyte secretion, concentration as low as 0.5 mg/ml of cementum from diseased sites raised the levels of TNF alpha and IL-1 beta secretion 10-fold. This response was dose-dependent. Diseased cementum were found to contain 1.5 ng/mg endotoxin, while endotoxin was not detectable in the extracts of the healthy cementum. However, neutralization of the endotoxin by polymyxin B only partially reduced the monocyte secretory response by 50 to 70%, suggesting that other factors in the extracts are also involved in monocyte stimulation. To simulate the effect of root conditioning, cementum was first agitated in a tetracycline or control solution prior to its extraction in media. Pretreatment of diseased cementum with tetracycline (50 mg/ml) was found to block the secretion of TNF alpha from cementum-stimulated monocytes. Pretreatment of the diseased cementum with 10 mg/ml tetracycline was not more effective than saline and HCI controls, with all treatments reducing cytokine secretion by approximately 80%. The direct addition of tetracycline to cementum-stimulated monocyte culture was found to block TNF alpha secretion in a dose dependent manner. The results suggest that extracts from diseased cementum are potent stimulators of monocyte secretion, and that endotoxin as well as other factor(s) appear to be involved. These factors are partially extracted by washing and a 10 mg/ml tetracycline solution is not more effective than saline in achieving this goal. In addition, tetracycline was found to be a potent inhibitor of TNF alpha secretion by cementum-stimulated monocytes, suggesting a novel mechanism for this drug in periodontal therapy.     

Treatment of root fracture by CO2 and Nd:YAG lasers: an in vitro study

The purpose of this in vitro study was to use scanning electron microscopy and polarized light microscopy to evaluate the feasibility of using either the CO2 laser or an Nd:YAG laser in combination with air/water surface cooling to effect fusion of fractured tooth roots. The experimental unit consisted of 81 single-rooted teeth, each with an induced root fracture. Fifty-six teeth that had been reapproximated in dental stone and 25 teeth that had been reapproximated with C-clamps were assigned to untreated control groups or groups for treatment using CO2 and Nd:YAG lasers. Laser treatment consisted of multiple passes along the line of fracture, which was inspected using a dissecting microscope after each pass until a visual indication of fusion or irreparable damage resulted. Scanning electron microscopy evaluation of the treated lines revealed heat-induced fissures and cracks, areas of cementum meltdown and resolidification, crater formation, and separation of cementum from underlying dentin. In no instance-regardless of reapproximation technique, laser type, energy, and other parameters-did the treatment effect fusion of the fractured root halves.     

Effects of guided bone regeneration around commercially pure titanium and hydroxyapatite-coated dental implants. II. Histologic analysis

The purpose of this study was to determine which treatment of a large osseous defect adjacent to an endosseous dental implant would produce the greatest regeneration of bone and degree of osseointegration: barrier membrane therapy plus demineralized freeze-dried bone allograft (DFDBA), membrane therapy alone, or no treatment. The current study histologically assessed changes in bone within the healed peri-implant osseous defect. In a split-mouth design, 6 implants were placed in edentulous mandibular ridges of 10 mongrel dogs after preparation of 6 cylindrical mid-crestal defects, 5 mm in depth, and 9.525 mm in diameter. An implant site was then prepared in the center of each defect to a depth of 5 mm beyond the apical extent of the defect. One mandibular quadrant received three commercially pure titanium (Ti) screw implants (3.75 x 10 mm), while the contralateral side received three hydroxyapatite (HA) coated root-form implants (3.3 x 10 mm). Consequently, the coronal 5 mm of each implant was surrounded by a circumferential defect approximately 3 mm wide and 5 mm deep. The three dental implants in each quadrant received either DFDBA (canine source) and an expanded polytetrafluoroethylene membrane (ePTFE), ePTFE membrane alone, or no treatment which served as the control. Clinically, the greatest increase in ridge height and width was seen with DFDBA/ePTFE. Histologically, statistically significant differences in defect osseointegration were seen between treatment groups (P < 0.0001: DFDBA/ePTFE > ePTFE alone > control). HA-coated implants had significantly greater osseointegration within the defect than Ti implants (P < 0.0001). Average trabeculation of newly formed bone in the defect after healing was significantly greater for HA-coated implants than for titanium (P < 0.0001), while the effect on trabeculation between treatments was not significantly different (P = 0.14). Finally, there were significantly less residual allograft particles in defect areas adjacent to HA-coated implants than Ti implants (P = 0.0355). The use of HA-coated implants in large size defects with DFDBA and ePTFE membranes produced significantly more osseointegration histologically than other treatment options and more than Ti implants with the same treatment combinations. The results of this study indicate that, although the implants appeared osseointegrated clinically after 4 months of healing, histologic data suggest that selection of both the implant type and the treatment modality is important in obtaining optimum osseointegration in large size defects.