Histologic comparison of light emitting diode phototherapy-treated hydroxyapatite-grafted extraction sockets: a same-mouth case study

BACKGROUND: The stimulating effect of red and near-infrared (NIR) laser phototherapy on bone regeneration and growth has been shown in a number of in vitro and animal studies. However, the effect of NIR phototherapy on the bone regeneration of hydroxyapatite (HA) -treated extraction sockets has not been previously demonstrated. MATERIALS AND METHODS: An investigational Biolux extraoral light emitting diode phototherapy device was used daily for 21 days postextraction and socket grafting with HA (Osteograf LD300) unilaterally. Bone regeneration of the phototherapy-treated and nontreated side was compared in same-mouth extraction sockets. RESULTS: Histologic evaluations showed enhanced bone formation and faster particle resorption associated with the phototherapy-treated socket graft compared with the non-phototherapy-treated socket. CONCLUSIONS: The accelerated bone healing in the phototherapy-treated HA socket graft may provide faster implant placement compared to non-phototherapy-treated socket grafts.     

Human histologic and histomorphometric analysis comparing OsteoGraf/N with PepGen P-15 in the maxillary sinus elevation procedure: a case report

The use of the anorganic bovine bone mineral OsteoGraf/N combined with demineralized freeze-dried bone allograft has received widespread use in sinus elevations. This composite graft material has proven to be suitable, predictable, and successful for the placement and integration of endosseous implants in the edentulous, atrophic maxilla. In this case study, the current materials and accepted methodology were compared with the latest tissue-engineered bone replacement graft material, PepGen P-15. PepGen P-15 is a combination of OsteoGraf/N and a synthetic peptide (P-15) that mimics the cell-binding domain of Type-I collagen responsible for cell migration, differentiation, and proliferation. The radiographic, histologic, and histomorphometric evaluations of the sinus grafted with PepGen P-15 showed enhanced bone formation within a shorter time interval compared with the composite graft material of OsteoGraf/N and demineralized freeze-dried bone allograft.     

8-year onlay bone graft and ridge augmentation with PepGen P-15: a clinical and radiographic case study

The long-term efficacy of PepGen P-15, a tissue-engineered particulate bone replacement graft, has been established for the treatment of periodontal osseous defects. In this case study, the long-term benefits of PepGen P-15 as a bone replacement graft for onlay grafting and ridge augmentation is evaluated using clinical and radiographic assessments. The radiographic and clinical evaluations continued for a period of over 8 years to confirm the stability of the onlay/ridge augmentation site grafted with PepGen P-15 particulate.     

Comparison of bone grafting materials in human extraction sockets: clinical, histologic, and histomorphometric evaluations

PURPOSE: Although there are a number of bone replacement graft materials that are currently available for clinical use, there are few studies that directly compare efficacy among graft treatments before implant placement. The purpose of this report was to compare 3 bone replacement graft materials (PepGen P-15 228 FLOW [DENTSPLY Friadent CeraMed, Lakewood, CO], Puros [Zimmer Dental, Carlsbad, CA], and C-Graft 228 [Clinician's Preference, Golden, CO]) for bone formation by clinical, histologic, and histomorphometric evaluation. MATERIALS AND METHODS: In this prospective, intraoral pilot study, 13 maxillary sockets in 2 patients (both smokers) were grafted immediately after tooth extraction with C-Graft 228, Puros, or PepGen P-15 228 FLOW (containing additional PepGen P-15 228 particles; FLOW PUTTY). After 4 months, bone cores were retrieved and analyzed histologically. RESULTS: PepGen P-15 228 FLOW PUTTY produced a significantly (P <0.01) higher amount of vital bone than C-Graft 228 or Puros. The amount of vital bone for FLOW PUTTY was 12-fold higher than for C-Graft 228 and 4-fold higher than Puros. Of 7 FLOW PUTTY treated sites, 7 showed >14% vital bone versus 0 of 3 C-Graft 228 and 0 of 3 Puros treated sites. FLOW PUTTY treated sites showed new vital bone between particles of residual graft. C-Graft 228 treated sites showed residual particles in a background of connective tissue with very little bone. Puros treated sites showed nonvital bone particles in a background of connective tissue, with some new vital bone forming around the nonvital bone. CONCLUSION: PepGen P-15 228 FLOW PUTTY produced significantly greater vital bone as compared to Puros and C-Graft 228 after 4 months. A larger clinical study is required to confirm these results.     

Dense hydroxyapatite inserted into postextraction sockets: a histologic and histomorphometric 20-year case report

BACKGROUND: The biologic behavior, i.e., the degradation of hydroxyapatite (HA) in the human body, is of relevance for clinicians. The present investigation is a long-term (20-year) histologic and histomorphometric evaluation of dense HA used in postextraction sockets. METHODS: Dense HA particles were used in a patient in postextraction alveolar sockets to maintain the alveolar ridge height. The patient returned after 20 years for implant treatment. A ridge remodeling was necessary during implant insertion surgery, and the HA/bone tissue was harvested with bone-cutting forceps from the canine and premolar area. The specimen was processed for histology and histomorphometry at the Implant Retrieval Centre, Dental School, University of Chieti-Pescara. RESULTS: Most of the particles (56%) were surrounded partially by bone, whereas some particles (39%) were surrounded completely. At higher magnification, bone was in close contact with the particles, and neither gaps nor fibrous tissues were present at the bone-biomaterial interface. Microscopically, the particles had a dense appearance. In only a few fields, it was possible to observe that the outer part of some particles had detached from the original particles' surface. Histomorphometry showed that bone represented 25.4% +/- 3.2%, marrow spaces represented 41.3% +/- 5.2%, and residual HA particles represented 38.1% +/- 4.1%. CONCLUSIONS: Intimate binding between bone and HA particles was present after a long-term implantation period (20 years). The fact that HA particles were surrounded closely by bone is very promising for the long-term stability of the augmentation.     

Clinical and histomorphometric evaluation of extraction sockets treated with an autologous bone marrow graft

Purpose: The aim of this study was to evaluate the potential of an autologous bone marrow graft in preserving the alveolar ridges following tooth extraction. Materials: Thirteen patients requiring extractions of 30 upper anterior teeth were enrolled in this study. They were randomized into two groups: seven patients with 15 teeth to be extracted in the test group and six patients with 15 teeth to be extracted in the control group. Hematologists collected 5 ml of bone marrow from the iliac crest of the patients in the test group immediately before the extractions. Following tooth extraction and elevation of a buccal full‐thickness flap, titanium screws were positioned throughout the buccal to the lingual plate and were used as reference points for measurement purposes. The sockets were grafted with an autologous bone marrow in the test sites and nothing was grafted in the control sites. After 6 months, the sites were re‐opened and bone loss measurements for thickness and height were taken. Additionally, before implant placement, bone cores were harvested and prepared for histologic and histomorphometric evaluation. Results: The test group showed better results (P<0.05) in preserving alveolar ridges for thickness, with 1.14±0.87 mm (median 1) of bone loss, compared with the control group, which had 2.46±0.4 mm (median 2.5) of bone loss. The height of bone loss on the buccal plate was also greater in the control group than in the test group (P<0.05), 1.17±0.26 mm (median 1) and 0.62+0.51 (median 0.5), respectively. In five locations in the control group, expansion or bone grafting complementary procedures were required to install implants while these procedures were not required for any of the locations in the test group. The histomorphometric analysis showed similar amounts of mineralized bone in both the control and the test groups, 42.87±11.33% (median 43.75%) and 45.47±7.21% (median 45%), respectively. Conclusion: These findings suggest that the autologous bone marrow graft can contribute to alveolar bone repair after tooth extraction. To cite this article:
Pelegrine AA, da Costa CES, Correa MEP, Marques JFC Jr. Clinical and histomorphometric evaluation of extraction sockets treated with an autologous bone marrow graft.
Clin. Oral Impl. Res. 21 , 2010; 535–542.
doi: 10.1111/j.1600‐0501.2009.01891.x     

Clinical,radiographic, and histologic study of endodontic treatment failures

One hundred fifty cases of endodontic treatment failures were studied clinically, radiographically, and histologically. Fifty-seven percent of the teeth were asymptomatic. Pain alone and/or associated with swelling was present in 21% of the teeth. There was no correlation between the size of periradicular rarefaction and the occurrence or severity of clinical signs and/or symptoms. Stainable bacteria were demonstrated in 69% of the teeth and were present mostly in the canal. The severity of periradicular inflammation was related to presence of stainable bacteria in the canal. Swelling and pain or a draining sinus tract was often associated with stainable bacteria inside the canal. The development of a radicular cyst associated with an endodontically treated tooth that has failed is not necessarily the cause of endodontic treatment failure.     

拔牙窝内植入不同深度骨水平种植体周围软硬组织改建的组织形态变化

目的 比较新鲜拔牙窝内植入不同深度种植体后软、硬组织的变化。方法 6只成年拉布拉多犬的双侧前磨牙拔除后,立即将24颗种植体以不同深度植入拔牙窝内。将Straumann^®骨水平种植体按以下不同深度植入拔牙窝—颊侧牙槽嵴下2 mm,颊侧牙槽嵴下1 mm,与牙槽嵴齐平,以及颊侧牙槽嵴上方1 mm。愈合6个月后采集样本,获得未脱钙切片,进行组织学观察、测量,获得垂直骨吸收和生物学宽度。采用SPSS 19.0软件包对数据进行统计学分析。结果 所有种植体均获得成功骨结合。骨吸收以种植体植入牙槽嵴下2 mm处最显著（P<0.05）。以不同深度植入时,生物学宽度无显著差别。结论 在新鲜拔牙窝内植入种植体时,不同植入深度对骨吸收有影响。当植入深度为骨下2 mm时,骨吸收最多。     

Influence of implant positioning in extraction sockets on osseointegration: histomorphometric analyses in dogs

Aim: To evaluate the influence of implant positioning into extraction sockets on osseointegration. Material and methods: Implants were installed immediately into extraction sockets in the mandibles of six Labrador dogs. In the control sites, the implants were positioned in the center of the alveolus, while in the test sites, the implants were positioned 0.8 mm deeper and more lingually. After 4 months of healing, the resorptive patterns of the alveolar crest were evaluated histomorphometrically. Results: All implants were integrated in mineralized bone, mainly composed of mature lamellar bone. The alveolar crest underwent resorption at the control as well as at the test sites. After 4 months of healing, at the buccal aspects of the control and test sites, the location of the implant rough/smooth limit to the alveolar crest was 2±0.9 mm and 0.6±0.9 mm, respectively (P<0.05). At the lingual aspect, the bony crest was located 0.4 mm apically and 0.2 mm coronally to the implant rough/smooth limit at the control and test sites, respectively (NS). Conclusions: From a clinical point of view, implants installed into extraction sockets should be positioned approximately 1 mm deeper than the level of the buccal alveolar crest and in a lingual position in relation to the center of the alveolus in order to reduce or eliminate the exposure above the alveolar crest of the endosseous (rough) portion of the implant. To cite this article:
Caneva M, Salata LA, de Souza SS, Baffone G, Lang NP, Botticelli D. Influence of implant positioning in extraction sockets on osseointegration: histomorphometric analyses in dogs.
Clin. Oral Impl. Res. 21 , 2010; 43–49.     

Bone marrow aspirate concentrate and platelet-rich fibrin in fresh extraction sockets: A histomorphometric and immunohistochemical study in humans

The aim of this study was to evaluate the level of mineralized tissue and expression of bone markers in sockets grafted with platelet-rich fibrin and bone marrow aspirate concentrate (BMAC).Patients requiring extraction of one maxillary anterior tooth were randomized into three groups. After tooth extraction, the sockets in the control group (CG) were permitted to fill with blood clot. In the platelet-rich fibrin group (PRFG), after blood processing, the sockets were grafted with PRF plug. In the bone marrow aspirate concentrate combined with platelet-rich fibrin group (BM/PG), after blood and bone marrow processing, the sockets were grafted with a mixture of PRF plug and BMAC. After 6 months, the sites were reopened and bone cores were harvested and prepared for histomorphometric and immunohistochemical evaluation. The following levels were measured: mineralized tissue, expression of RUNX-2, and osteocalcin.Fifteen patients were included in this study. The histomorphometric analysis showed a more pronounced level of mineralized tissue in PRFG and BM/PG (54.20 ± 4.31% and 64.70 ± 6.74%, respectively) when compared with CG (40.60 ± 5.98%) (p = 0.0283 and p = 0.0090, respectively). The expression of RUNX-2 was very low in BM/PG (0.80 ± 0.84%) and absent in CG and PRFG (p = 0.0528). Osteocalcin expression was higher for BM/PG (23.40 ± 1.52%) when compared with CG and PRFG (18.40 ± 2.07% and 16.20 ± 1.92%, respectively) (p = 0.0117 and p = 0.0088, respectively).This preliminary study indicates that clinical use of bone marrow aspirate concentrate, when combined with platelet-rich fibrin as a carrier, might have some potential to increase mineralization in fresh extraction sockets.     

Effect of bismuth subgallate (a hemostatic agent) on bone repair; a histologic,radiographic and histomorphometric study in rats

Bismuth subgallate (BS) is a hemostatic agent used for soft tissue surgery in otorhinolaryngology and dermatology. Its effect on bone repair has not been studied. The present study undertook a quantitative and qualitative evaluation of post-extraction bone healing in the presence of BS. Under intraperitoneal anesthesia, forty male Wistar rats, 80 ± 5 g body weight, underwent the extraction of both lower first molars. BS was placed in the right post-extraction socket (group E) and the contralateral socket served as control (group C). The animals were killed in groups immediately, 7, 14 and 30 days post-extraction. The mandibles were resected, radiographed and processed for embedding in paraffin. The mesial socket was sectioned along the bucco-lingual axis and stained with hematoxylin-eosin. Total tissue volume and trabecular bone volume of the apical third of the sockets were determined histomorphometrically. At 14 and 30 days post-extraction, group E exhibited bone tissue that resembled that of group C. Histomorphometric analyses showed no statistically significant differences between groups C and E. Bismuth subgallate did not interfere with post-extraction bone healing. Further studies will analyze the effect of this hemostatic agent on bone repair in aniticoagulated rats.     

Alveolar wound healing and ridge remodeling after tooth extraction in the rat: a histologic, radiographic, and histometric study

Healing of extraction wounds in rats was analyzed by histologic, radiographic and histometric methods at 0, 7, 14, 30, 60 days after tooth removal. Total alveolar volume, volume density of bone, percentage of bone formation, bone resorption areas, and height of both vestibular and lingual crests were analyzed. Total alveolar bone volume and bone density in the apical third increased from 0 to 60 days. Maximum bone formation was observed at 14 days, whereas the greatest bone resorption was observed seven days after extraction. The height of the lingual crest was lowest 14 days postextraction and then increased progressively to day 60.     

Electrical field effect on peri-implant osteogenesis: a histologic and histomorphometric study

PURPOSE: Tissue response to injury, as occurs during wound healing, is a well-organized biologic event. Both clinical and experimental studies have shown external electrical stimulation to enhance tissue repair. The effect of in situ electrical stimulation has been studied in experimental models of fracture healing, ostectomy, osteogenic distraction, and implants. The aim of the present study was to evaluate the effect of an electrical field on peri-implant wound healing, using an experimental model that involved placing a metallic laminar implant in rat tibia. MATERIALS: Forty male Wistar rats weighing approximately 100 g were used. A titanium laminar implant (6 x 1 x 0.1 mm3) (Implant Vel, Buenos Aires, Argentina) was inserted through the hole and placed in the medullary compartment. The tissues were then repositioned and sutured carefully. An electric field generator (ECCEL, DAM, Argentina) was used to deliver the electric stimulus. The electric field plate was placed on the skin of both hind limbs. In sham group, the animals were subjected to the same procedure without connecting the plate to the electric field generator. All the animals were killed by ether overdose at 15 days of postimplantation. The tibiae were resected, fixed in 20% formalin, radiographed, and processed for embedding in methyl methacrylate. The ground sections were stained with 1% toluidine blue. The following parameters were evaluated: peri-implant bone volume and percentage of osseointegration. Statistical analysis of the results was performed using ANOVA (P < 0.05). RESULTS: Application of external positive or negative electrical fields using the experimental model (post-titanium implant bone healing in rat tibia), under the conditions stated herein, was found to enhance peri-implant lamellar bone volume compared with sham-treated animals. CONCLUSION: The use of a device generating a positive/negative electrical field resulted in the presence of woven bone.     

Extraction sockets and implantation of hydroxyapatites with membrane barriers: a histologic study

The purpose of this pilot study was to investigate the effect on extraction socket healing when an absorbable hydroxyapatite (AH) and a nonabsorbable anorganic bovine bone mineral (ABB) covered with either an acellular dermal matrix allograft (ADMA) or expanded polytetrafluoroethylene (ePTFE) membrane barrier were left exposed to the oral cavity. Following tooth extraction, a total of 16 sockets in 15 patients with deficient buccal plates of > or =5 mm were randomly divided into 4 treatment groups: 1) AH covered with ADMA, 2) AH covered with an ePTFE membrane, 3) ABB covered with ADMA, and 4) ABB covered with an ePTFE membrane. Primary coverage was not attempted or obtained in any of the 16 treated sockets. Six to 8 months postextraction at the time of implant placement, histologic cores of the treatment sites were obtained. These cores were processed, stained with Stevenel's blue/van Gieson's picro fuchsin, and histomorphometrically analyzed. Vital bone, connective tissue and marrow, and residual graft particles were reported as a percentage of the total core. The mean vital bone was 34.5% (AH with ADMA), 41.7% (ABB with ADMA), 27.6% (ePTFE and AH), and 17.8% (ePTFE and ABB). The average percentage of vital bone in the 8 sockets covered with ADAMA was 38% compared with an average percentage vital bone of 22% in the 8 sockets covered with ePTFE membrane barriers. Because of the small number of specimens in the 4 groups, statistical analysis was not possible. However, in this pilot study, ADMA-covered sites resulted in more vital bone present 6 to 8 months postsocket treatment than obtained in the ePTFE-covered sites regardless of bone replacement materials used. Further research is warranted to see if these results show a similar difference in bone-to-implant contact after implant placement.     

Immediate loading of modular transitional implants: a histologic and histomorphometric study in dogs

Modular Transitional Implants (MTI) are made from pure titanium and are used to support fixed provisional restorations during the osseointegration of definitive implants. This study histologically examined the jaw response to loaded MTIs in the dog mandible. Three implants were inserted transmucosally into each side of the mandible in 3 dogs. Stability was examined using a Periotest. Anterior and posterior implants were splinted using a cemented acrylic resin fixed partial denture to allow immediate loading. The middle implant remained unloaded and was used as a control. Dogs were sacrificed 11 to 12 weeks after implantation, and tissue blocks containing the implants were removed. Histologic examination showed that 10 of the 18 implants had good bone-to-implant contact, with the percentage of bone contacting the threaded portion of the implant varying from 30% to 65%. There was no statistical difference (p > 0.1) in percentage of bone-to-metal contact between loaded and unloaded implants. Six implants were entirely surrounded by connective tissue with or without inflammation; two implants were lost during the study. The success rate did not differ between loaded and unloaded implants. In the successful implants trabecular bone made good contact with the implant, forming supporting struts. There was bone remodeling in some bone-to-metal contact areas. It is believed that success was mainly influenced by the initial bone density at the implant site and by the uncontrolled load that the animals applied to the implants during the early healing stage.     

Alveolar wound healing after x-irradiation: a histologic, radiographic, and histometric study

Healing of extraction wounds in rats following cephalic irradiation was studied by histologic, radiographic, and histometric methods 14 days after tooth extraction. Irradiation was given at 0, 3, and 7 days after surgery in doses of either 15, 20, or 30 Gy. No significant differences were seen with the different doses given seven days post-extraction. However, socket healing was delayed when irradiation was given immediately and three days after extraction. On the basis of these observations, it is recommended that radiation not begin until at least one week after the extraction of teeth.