Conceptualisation and Implementation of a Competency-based Multidisciplinary Course for Medical Students in Neurosurgery.

The field of medicine is quickly evolving and becoming increasingly more multidisciplinary and technologically demanding. Medical education, however, does not yet adequately reflect these developments and new challenges, which calls for a reform in the way aspiring medical professionals are taught and prepared for the workplace. The present article presents an attempt to address this shortcoming in the form of a newly conceptualized course for medical students with a focus on the current demands and trends in modern neurosurgery. Competency-based education is introduced as a conceptual framework comprising academic and operational competence as well as life-world becoming. This framework provides a sound educational foundation for future medical professionals, equipping them with the knowledge as well as skills needed to successfully navigate the medical field in the current day and age. Three competencies are identified that are central to day-to-day medical practice, namely digitalization, multidisciplinarity, and the impact of recent developments on the changing patient-practitioner relationship. These competencies are relevant for all medical disciplines, but are demonstrated here in a neurosurgical context and visualized using a real patient's case study. Students follow this sample patient's way through each step of the neurosurgical workflow, from planning to performing the procedure, and can see for themselves the importance and application of the aforementioned competencies based on this real-world example. Courses such as the one presented here may prepare medical students more adequately for their future work by combining theoretical and practical skills and critical reflection, thereby providing holistic and practical insights as well as a conceptual framework for their future careers.

Absence of histologic signs of chronic inflammation following closed subgingival scaling and root planing using the dental endoscope: human biopsies - a pilot study.

BACKGROUND: The primary goal of periodontal therapy is the reduction or elimination of inflammation. Traditionally, this is accomplished through removal of subgingival tooth-borne accretions using non-surgical and/or surgical treatment modalities. Numerous studies indicated the difficulty in removing these accretions to the point that histologic manifestations of chronic inflammation are eliminated. A companion to the current study demonstrated that subgingival inflammation was associated most often with calculus covered with biofilm, not biofilm alone. This pilot study evaluated the histologic response in humans to removal of calculus and biofilm with the aid of the dental endoscope. METHODS: Twelve teeth in six patients were identified as test teeth, and all subgingival deposits visible with the endoscope were removed in a single treatment by an operator experienced in root planing and the use of the dental endoscope. The 12 teeth and the coronal portion of their periodontal attachment apparatus were removed 6 months after a single episode of closed subgingival scaling and root planing. Biopsies were processed for histologic evaluation. RESULTS: There were no histologic signs of chronic inflammation. Deposits of calculus and biofilm were seen on one section of one tooth but apparently were deposited after initial therapy. Bone repair and the growth of a long junctional epithelium were observed on previously diseased root surfaces. CONCLUSION: Histologic signs of chronic inflammation were absent 6 months after a single course of closed subgingival scaling and root planing using the dental endoscope.

The effect of rhBMP-2 around endosseous implants with and without membranes in the canine model.

BACKGROUND: Bone morphogenetic protein (BMP) is a potent differentiating agent for cells of the osteoblastic lineage. It has been used in the oral cavity under a variety of indications and with different carriers. However, the optimal carrier for each indication is not known. This study examined a synthetic bioabsorbable carrier for BMP used in osseous defects around dental implants in the canine mandible. METHODS: Twelve canines had their mandibular four premolars and first molar teeth extracted bilaterally. After 5 months, four implants were placed with standardized circumferential defects around the coronal 4 mm of each implant. One-half of the defects received a polylactide/glycolide (PLGA) polymer carrier with or without recombinant human BMP-2 (rhBMP-2), and the other half received a collagen carrier with or without rhBMP-2. Additionally, one-half of the implants were covered with a non-resorbable (expanded polytetrafluoroethylene [ePTFE]) membrane to exclude soft tissues. Animals were sacrificed either 4 or 12 weeks later. Histomorphometric analysis included the percentage of new bone contact with the implant, the area of new bone, and the percentage of defect fill. This article describes results with the PLGA carrier. RESULTS: All implants demonstrated clinical and radiographic success with the amount of new bone formed dependent on the time and presence/absence of rhBMP-2 and presence/absence of a membrane. The percentage of bone-to-implant contact was greater with rhBMP-2, and after 12 weeks of healing, there was approximately one-third of the implant contacting bone in the defect site. After 4 weeks, the presence of a membrane appeared to slow new bone area formation. The percentage of fill in membrane-treated sites with rhBMP-2 rose from 24% fill to 42% after 4 and 12 weeks, respectively. Without rhBMP-2, the percentage of fill was 14% rising to 36% fill, respectively. CONCLUSIONS: After 4 weeks, the rhBMP-2-treated sites had a significantly higher percentage of contact, more new bone area, and higher percentage of defect fill than the sites without rhBMP-2. After 12 weeks, there was no significant difference in sites with or without rhBMP-2 regarding percentage of contact, new bone area, or percentage of defect fill. In regard to these three outcomes, comparing the results with this carrier to the results reported earlier with a collagen carrier in this study, only the area of new bone was significantly different with the collagen carrier resulting in greater bone than the PLGA carrier. Thus, the PLGA carrier for rhBMP-2 significantly stimulated bone formation around dental implants in this model after 1 month but not after 3 months of healing. The use of this growth factor and carrier combination appears to stimulate early bone healing events around the implants but not quite to the same degree as a collagen carrier.

A study of the fate of the buccal wall of extraction sockets of teeth with prominent roots.

The objective of this investigation was to determine the fate of thin buccal bone encasing the prominent roots of maxillary anterior teeth following extraction. Resorption of the buccal plate compromises the morphology of the localized edentulous ridge and makes it challenging to place an implant in the optimal position for prosthetic restoration. In addition, the use of Bio-Oss as a bone filler to maintain the form of the edentulous ridge was evaluated. Nine patients were selected for the extraction of 36 maxillary anterior teeth. Nineteen extraction sockets received Bio-Oss, and seventeen sockets received no osteogenic material. All sites were completely covered with soft tissue at the conclusion of surgery. Computerized tomographic scans were made immediately following extraction and then at 30 to 90 days after healing so as to assess the fate of the buccal plates and resultant form of the edentulous sites. The results were assessed by an independent radiologist, with a crest width of 6 mm regarded as sufficient to place an implant. Those sockets treated with Bio-Oss demonstrated a loss of less than 20% of the buccal plate in 15 of 19 test sites (79%). In contrast, 12 of 17 control sockets (71%) demonstrated a loss of more than 20% of the buccal plate. In conclusion, the Bio-Oss test sites outperformed the control sites by a significant margin. No investigator was able to predict which site would be successful without the grafting material even though all were experienced clinicians. This leads to the conclusion that a patient has a significant benefit from receiving grafting materials at the time of extraction.

The use of guided tissue regeneration principles in endodontic surgery for induced chronic periodontic-endodontic lesions: a clinical, radiographic, and histologic evaluation.

BACKGROUND: Chronic periodontic-endodontic lesions are not uncommon in clinical practice and their regenerative capacity has long been questioned. However, there are no published studies investigating the application of guided tissue regeneration techniques in combination with endodontic surgery using an induced perio-endo defect model. This study evaluated the clinical, radiographic, and histologic outcomes of three surgical procedures used to treat induced perio-endo lesions. METHODS: Pulpal necrosis was induced in foxhounds along with surgical removal of radicular buccal bone. After 4 weeks, chronic lesions were clinically and radiographically assessed. Treatment surgery consisted of apicoectomy, root canal instrumentation, and retrofilling with mineral trioxide aggregate. Teeth were then assigned to one of the following treatment groups: open flap debridement only (OFD), OFD with bioabsorbable porcine-derived collagen membrane (BG), or OFD with BG and anorganic bovine bone matrix (BO/BG). Clinical parameters and standardized radiographs were assessed at defect creation; treatment surgery; and at 1, 2, 4, and 6 months. Animals were sacrificed at 6 months and specimens prepared for histometric analysis. RESULTS: Clinical and radiographic conditions improved during the study period. Mean epithelial attachment was similar between all groups. Mean connective tissue attachment for groups OFD, BG, and BO/BG was 3.79 mm, 2.63 mm, and 1.75 mm, respectively, and mean radicular bone height was 2.16 mm, 3.24 mm, and 3.45 mm, respectively. Statistically significant increases in the amount of new cementum were observed in groups BG and BO/BG when compared with OFD (P <0.05). CONCLUSIONS: Treatment of combined induced perio-endo lesions using bioabsorbable collagen membranes alone or in combination with anorganic bovine bone matrix resulted in increased amounts of bone, periodontal ligament, and significant increases in the amount of new cementum when compared to open flap debridement in a canine model.

Membrane durability and tissue response of different bioresorbable barrier membranes: a histologic study in the rabbit calvarium.

PURPOSE: The objective of the present study was to histologically evaluate barrier durability and host tissue response of new prototype collagen membranes in comparison to clinically available collagen and synthetic polymer membranes. MATERIALS AND METHODS: The experimental study was conducted in 20 rabbits with 4 different healing periods of 2, 6, 12, and 28 weeks. Following surgical exposure of the calvarium, 6 circular bone defects (diameter 4 mm, depth 1.5 mm) were drilled into the outer cortex. After the bone had been removed, each defect was covered with 1 of 6 different membranes: 3 collagen prototype membranes, a Bio-Gide collagen membrane (BG), a glycolide-lactide-trimethylene carbonate Osseoquest membrane (OQ), and a polylactide Atrisorb membrane (AS). Histological analysis was performed following staining with toluidine blue and transversal sectioning of the calvarial bone. RESULTS: All collagen membranes showed similar tissue integration characterized by fibrous encapsulation with differentiation of a periosteumlike tissue upon the external bony surface. One prototype collagen membrane displayed clearly longer membrane integrity. The evaluated synthetic membranes demonstrated extended barrier durability but also exhibited inflammatory foreign-body reactions. DISCUSSION: Recent experimental investigations have shown that degradation of collagen membranes may begin within days to weeks of membrane placement. This was confirmed in the present study. However, 1 of the chemically modified collagen prototype membranes exhibited prolonged membrane integrity in the absence of an inflammatory tissue response. CONCLUSION: Further investigation of the prototype membrane that showed prolonged membrane integrity to evaluate its potential in GBR procedures is needed.

Bone regeneration in standardized bone defects with autografts or bone substitutes in combination with platelet concentrate: a histologic and histomorphometric study in the mandibles of minipigs.

PURPOSE: To evaluate the effect of the addition of platelet concentrate (PC) to autografts or bone substitutes on bone regeneration in standardized bone defects. MATERIALS AND METHODS: Three standardized bone defects were prepared in both mandibular angles of 12 adult minipigs. The defects were grafted with autograft, anorganic bovine bone, or synthetic beta-tricalcium phosphate (beta-TCP). PC was added to only 1 side. The animals were divided into 4 groups, which were sacrificed at 4 different time points (1, 2, 4, and 8 weeks) for histologic and histomorphometric analysis. The concentrations of platelets and growth factors were measured to identify correlation to the histologic and histomorphometric results. RESULTS: No correlation was found between platelet count in whole blood and platelet count in PC (r(p) = 0.36). Furthermore, no correlation could be demonstrated between the platelet count of the PC and the concentrations of PDGF-AB (r(p) = -0.27) and TGF-beta (r(p) = 0.34). There were no signs of a stimulating effect of PC on bone formation in combination with autografts or bone substitutes at any time point (P = .89). Addition of PC did not alter the pattern of graft degradation. DISCUSSION: The present study underlines the need for further investigation to identify the optimal concentrations of platelets and combinations of growth factors to achieve a predictable stimulatory effect on bone regeneration. One of the first steps to achieve this goal will be the development of a reliable method for the procurement of PC. CONCLUSION: PC had no impact on bone formation and graft degradation in standardized bone defects in the mandibles of minipigs.

Immediate and early loading of SLA ITI single-tooth implants: an in vivo study.

PURPOSE: The purpose of this investigation was to determine whether early and immediate loading of dental implants resulted in adverse consequences as determined clinically, radiographically, and histologically. MATERIALS AND METHODS: In a canine model, 48 sand-blasted, large-grit, acid-etched (SLA) surfaced implants were placed at 4 different times before definitive restoration and loading. These times were 3 months (group A), 21 days (group B), 10 days (group C), and 2 days (immediately) (group D) before loading. Each implant was restored at the same time with a single gold screw-retained crown. Immediately after restoration all crowns were placed in function. Standardized periapical radiographs were made 1, 2, and 3 months after restoration. At the end of the study, block sections were obtained for histologic examination. Changes in crestal bone height on the mesial and distal aspects of each implant and the change in bone density of the coronal 3 mm of crestal bone were recorded. Primary, secondary, and total bone-to-implant contact; bone marrow-to-implant contact; and connective tissue-to-implant contact were evaluated histologically. RESULTS: All implants were osseointegrated at the end of the study; no clinical failures of integration were noted. The changes in crestal bone heights for groups A, B, C, and D (means +/- SE) were 0.02 +/- 0.07 mm, 0.30 +/- 0.08 mm, 0.15 +/- 0.08 mm, and 0.35 +/- 0.18 mm, respectively. Total bone-to-implant contact for the 4 groups was 69.1%, 71.3%, 74.6%, and 75.2%, respectively (P > .57). DISCUSSION: Under the conditions of this study no statistically significant differences were noted between the 4 different loading protocols for any of the parameters recorded. This finding is consistent with other recent studies and case reports. CONCLUSION: The findings of this study indicate that early and immediate loading of single-unit SLA surfaced implants was possible in this model. (More than 50 references.)

Osseous response following resective therapy with piezosurgery.

A piezoelectric instrument vibrating in the ultrasonic frequency range was investigated for its potential use in periodontal resective therapy. The rate of postoperative wound healing (baseline and 14, 28, and 56 days after surgery) in a dog model following surgical ostectomy and osteoplasty was the marker used to compare the efficacy of this instrument (PS) with a commonly used carbide bur (CB) or a diamond bur (DB). The surgical sites treated by CB or DB lost bone, in comparison to baseline measurements, by the 14th day, while the surgical sites treated by PS revealed a gain in the bone level. By day 28, the surgical sites treated by all three instruments demonstrated an increased bone level and regeneration of cementum and periodontal ligament. However, by day 56, the surgical sites treated by CB or DB evidenced a loss of bone, versus a bone gain in the PS-treated sites. Thus, it appears that PS provided more favorable osseous repair and remodeling than CB or DB when surgical ostectomy and osteoplasty procedures were performed. Therefore, PS could be regarded as being efficacious for use in osseous surgery.

New model for simulation of fracture repair in full-grown beagle dogs: model characterization and results from a long-term study with ibandronate.

INTRODUCTION: Given that bisphosphonates reduce bone turnover, it is important to establish that their long-term administration does not impair bone quality. This paper describes a new model for simulation of fracture repair to evaluate several aspects of bone quality following long-term administration (34 or 36 weeks) of ibandronate in full-grown beagle dogs. METHODS: The treatment schedule consisted of continuous daily subcutaneous administration of a pharmacologically active dose (1 microg/kg/day) and two cyclical intermittent regimens providing a similar total dose per animal at the end of the experiment. Seven or 8 weeks before study end, 10 holes were drilled in the left tibia and bone marrow ablation was performed in the ipsilateral femur. Serial measurements for blood biochemistry (osteocalcin and iso-alkaline phosphatase) and bone mineral density (BMD; whole body and L1-L7) by dual-energy X-ray absorptiometry (DEXA) were performed during the experiment. Bone quality was determined at the end of the experiment by assessing early and late stage defect healing and structural, cellular, and dynamic histomorphometry (femur, tibia, and lumbar vertebrae L3 and L4). RESULTS: Healing of the drill hole defects, which simulate the first stage of fracture healing, was neither qualitatively nor quantitatively influenced by ibandronate. The same was true for the activation of cortical remodeling that occurs in the later stage of fracture healing, which started in Week 4 after surgery and declined after Week 8 in all groups. Additionally, no difference was found between the various regimens and the controls with respect to DEXA analyses, trabecular bone volume, cancellous bone tissue area, cancellous bone perimeter, osteoclast count, serum osteocalcin, or bone-specific alkaline phosphatase. DISCUSSION: In conclusion, the presence of the first and second steps of fracture healing and the fact that the histological features closely resemble those of fracture repair validate the development and characterization of a new model for simulation of fracture repair. A long-term study with a therapeutically active dose of ibandronate shows that ibandronate does not impair BMD, bone structure, bone repair, coupling, and serum parameters for bone formation and turnover after long-term administration.

Histological evaluation of 4 cases of root coverage following a connective tissue graft combined with an enamel matrix derivative preparation.

BACKGROUND: The purpose of this report was to evaluate the histological characteristics of 4 clinically successful root coverage procedures performed with a combination of a connective tissue (CT) graft and an enamel matrix derivative (EMD) preparation. METHODS: Four maxillary teeth (3 canines and 1) first premolar) that presented with mucogingival problems and Miller's Class II and III gingival recession were evaluated in the study. Surgical therapy for root coverage consisted of autogenous CT grafts combined with the topical application of EMD. Following healing, treated teeth were extracted with a portion of their buccal attachment apparatus. Two teeth were extracted at 6 months and 2 teeth at 1 year postoperatively. Specimens were prepared for histology and analyzed by light microscopy. RESULTS: All treated teeth presented with clinical signs of successful root coverage. Histological observations of the 4 specimens revealed similar findings. The junctional epithelium was < or = 2 mm long. Apical to the junctional epithelium, dense CT fibers were found in close proximity to the root surface, but in general, no insertion of these fibers into the root was observed. In one 6-month specimen, formation of new cementum and new bone was observed in the most apical end of the grafted area. CONCLUSIONS: The results of this study suggest that a combination of CT grafts and EMD results mainly in an adhesion between the CT and root surface. Some periodontal regeneration may occur in some regions. The development of a long junctional epithelium was not observed with this combined therapy for the treatment of gingival recession.

Immediate implants covered with connective tissue membranes: human biopsies.

BACKGROUND: Osseointegration has been shown to occur around implants placed immediately after tooth extraction in humans. To date, such osseointegration has been achieved only with titanium plasma-sprayed (TPS) implants placed in extraction sockets with a bone-to-implant distance of less than 2 mm. In a previous report, when this horizontal defect dimension (HDD) exceeded 2 mm, the resulting percentage of bone-to-implant contact was reduced, indicating that the immediate technique would be limited in most cases to non-molar teeth. In an attempt to improve the bone-to-implant contact and the initial bone-to-implant contact in a vertical dimension, the implant surface, the type of membrane, and the method of membrane placement used in a previous study by our group were modified. METHODS: Ten large-grit sandblasted, acid-attacked (SLA) titanium implants were placed into immediate extraction sites in 5 patients. HDDs of 0.0 to 1.5 mm (controls), 1.5 to 4.0 mm, and >4.0 mm were used. Following insertion, implants were completely covered with a connective tissue membrane. This was in contrast to the use of an expanded polytetrafluoroethylene (ePTFE) membrane penetrated by the neck of the implant in our previous report. Primary closure of soft tissue flaps was achieved in each case. Six months after placement, 7 of the implants were histologically examined. RESULTS: Osseointegration occurred across all HDDs, with the percentage of bone-to-implant contact in the 0.0 to 1.5 mm HDDs similar to that seen in the >4.0 mm HDDs. The first bone-to-implant contact measured vertically was similar in both the smaller and larger HDDs. CONCLUSIONS: Osseointegration was successful in immediate implant placement sites with horizontal defect dimensions wider than 4 mm in humans when SLA titanium implants were completely covered with connective tissue membranes. It remains undetermined whether the different type of membrane, placement of the membrane, type of implant surface, or a combination of these 3 factors were responsible for the improved osseointegration in HDDs >4 mm. Further study is needed.

Periodontal regeneration in humans using recombinant human platelet-derived growth factor-BB (rhPDGF-BB) and allogenic bone.

BACKGROUND: Purified recombinant human platelet-derived growth factor BB (rhPDGF-BB) is a potent wound healing growth factor and stimulator of the proliferation and recruitment of both periodontal ligament (PDL) and bone cells. The hypothesis tested in this study was that application of rhPDGF-BB incorporated in bone allograft would induce regeneration of a complete new attachment apparatus, including bone, periodontal ligament, and cementum in human interproximal intrabony defects and molar Class II furcation lesions. METHODS: Nine adult patients (15 sites) with advanced periodontitis exhibiting at least one tooth requiring extraction due to an extensive interproximal intrabony and/or molar Class II furcation defect were entered into the study. Eleven defects were randomly selected to receive rhPDGF-BB. Following full-thickness flap reflection and initial debridement, the tooth roots were notched at the apical extent of the calculus, the osseous defects were thoroughly debrided, and the tooth root(s) were planed/prepared. The osseous defects were then filled with demineralized freeze-dried bone allograft (DFDBA) saturated with one of three concentrations of rhPDGF-BB (0.5 mg/ml, 1.0 mg/ml, or 5.0 mg/ml). Concurrently, four interproximal defects were treated with a well accepted commercially available graft (anorganic bovine bone in collagen, ABB-C) and a bilayer collagen membrane. Radiographs, clinical probing depths, and attachment levels were obtained preoperatively (at baseline) and 9 months later. At 9 months postoperatively, the study tooth and surrounding tissues were removed en bloc. Clinical and radiographic data were analyzed for change from baseline by defect type and PDGF concentration. The histologic specimens were analyzed for the presence of regeneration of a complete new attachment apparatus coronal to the reference notch. RESULTS: The post-surgical wound rapidly healed and was characterized by firm, pink gingivae within 7 to 10 days of surgery. There were no unfavorable tissue reactions or other safety concerns associated with the treatments throughout the course of the study. In rhPDGF/allograft sites, the vertical probing depth (vPD) reduction for interproximal defects was 6.42 +/- 1.69 mm (mean +/- SD) and clinical attachment level (CAL) gain was 6.17 +/- 1.94 mm (both P < 0.01). Radiographic fill was 2.14 +/- 0.85 mm. Sites filled with ABB-C had a PD reduction and CAL gain of 5.75 +/- 0.5 and 5.25 +/- 1.71, respectively. Furcation defects treated with rhPDGF/allograft exhibited a mean horizontal and vertical PD reduction of 3.40 +/- 0.55 mm (P < 0.001) and 4.00 +/- 1.58 mm (P < 0.005), respectively. The CAL gain for furcation defects was 3.2 +/- 2.17 mm (P < 0.030). Histologic evaluation revealed regeneration of a complete periodontal attachment apparatus, including new cementum, PDL, and bone coronal to the root notch in four of the six interproximal defects and all evaluable (four of four) furcation defects treated with PDGF. Two of the four interproximal intrabony defects treated with ABB-C and membrane exhibited regeneration. CONCLUSIONS: Use of purified rhPDGF-BB mixed with bone allograft results in robust periodontal regeneration in both Class II furcations and interproximal intrabony defects. This is the first report of periodontal regeneration demonstrated histologically in human Class II furcation defects.

Evaluation of periodontal regeneration following grafting intrabony defects with bio-oss collagen: a human histologic report.

This study evaluated the clinical, radiographic, and histologic response to Bio-Oss Collagen when used alone or in combination with Bio-Gide bilayer collagen membrane for the treatment of four intrabony defects (5 to 7 mm) around single-rooted teeth. After reflecting a full-thickness flap, thorough degranulation and root planing were accomplished. In all cases, Bio-Oss Collagen was then used to fill the defects, and in two cases, a Bio-Gide membrane was placed over the filled defect. Radiographs, clinical probing depths, and attachment levels were obtained before treatment and immediately preceding en bloc resection of teeth and surrounding tissues 9 months later. Reduction in pocket depth and gain in clinical attachment level were observed for both treatment protocols. The histologic evaluation demonstrated the formation of a complete new attachment apparatus, evidencing periodontal regeneration that varied with defect morphology. This human histologic study demonstrated that Bio-Oss Collagen has the capacity to induce regeneration of the periodontal attachment apparatus when placed in intrabony defects.

Healing of periapical lesions with complete loss of the buccal bone plate: a histologic study in the canine mandible.

This study evaluated periapical healing of induced apical lesions with concomitant loss of the buccal bone plate in a dog model using four foxhounds. In an initial surgery, pulp cavities of mandibular premolars were exposed to induce apical lesions. In the same session, the cortical bone covering the buccal root surfaces was surgically removed to simulate buccal bone loss. After radiographic confirmation of the development of apical lesions, sites were reentered for surgical treatment. Following apical and buccal debridement, root-end resection, and root-end filling, sites were subjected to three different treatment modalities: (1) flap readaptation (controls); (2) placement of a collagen membrane covering the apical defect and denuded root surface; or (3) placement of an anorganic bovine bone filler into the apical defect and onto the exposed buccal root surface, with additional application of a collagen membrane. Animals were sacrificed 7 months following the second surgery. Step sections were analyzed histometrically and morphometrically for periapical healing. Sites with membrane + filler showed a statistically significantly lower mean percentage of new bone formation within the former defect compared to both membrane-alone and control sites. No significant differences were found for tissue components deposited on the cut root face across treatment groups. Formation of a continuous thin layer of new cementum covering the exposed dentin surface and root-end filling material was a frequent finding. Analysis of the tissue regeneration on the buccal root aspect as well as the clinical periodontal parameters will be presented in a separate article.

Periodontal regeneration in human Class II furcations using purified recombinant human platelet-derived growth factor-BB (rhPDGF-BB) with bone allograft.

This human clinical trial evaluated the clinical and histologic response to recombinant human platelet-derived growth factor-BB (rhPDGF-BB) delivered in bone allograft for the treatment of advanced Class II furcation defects. Three mandibular and one maxillary molar furcation defects were treated: Two received 0.5 mg/mL and two received 1.0 mg/mL rhPDGF-BB, in all cases mixed with DFDBA. Clinical probing depths and attachment levels were obtained presurgically and 9 months postsurgical, after which the teeth and surrounding tissues were removed en bloc. Both concentrations of rhPDGF-BB resulted in substantially improved horizontal (mean 3.5 mm) and vertical (mean 4.25 mm) probing depths and attachment levels (mean 3.75 mm). Histologic evaluation revealed periodontal regeneration, including new bone, cementum, and periodontal ligament coronal to the reference notch. Regeneration was also present coronal to the original osseous crest In one case where an enamel projection extended into the fornix of the furcation, new calcified tissue with new inserting connective tissue fibers was observed over the enamel. This study documented the favorable tissue response to rhPDGF-BB treatment at both the clinical and microscopic levels, provided the first human histologic evidence that new calcified tissue with inserting collagen fibers can occur over enamel projections within furcations, and demonstrated for the first time that complete periodontal regeneration can be achieved in advanced Class II furcation defects using a combination of purified recombinant growth factor and bone allograft.

Integration of remote blood glucose meter upload technology into a clinical pharmacist medication therapy management service.

A pharmacist-delivered, outpatient-focused medication therapy management (MTM) program is using a remote blood glucose (BG) meter upload device to provide better care and to improve outcomes for its patients with diabetes. Sharing uploaded BG meter data, presented in easily comprehensible graphs and charts, enables patients, caregivers, and the medical team to better understand how the patients' diabetes care is progressing. Pharmacists are becoming increasingly more active in helping to manage patients' complex medication regimens in an effort to help detect and avoid medication-related problems. Working together with patients and their physicians as part of an interdisciplinary health care team, pharmacists are helping to improve medication outcomes. This article focuses on two case studies highlighting the Diabetes Monitoring Program, one component of the Meridian Pharmacology Institute MTM service, and discusses the clinical application of a unique BG meter upload device.

Evaluation of a novel biphasic calcium phosphate in standardized bone defects: a histologic and histomorphometric study in the mandibles of minipigs.

OBJECTIVE: A novel biphasic calcium phosphate (CaP) granulate consisting of hydroxyapatite (HA) and beta-tricalciumphosphate (TCP) was compared with pure HA and pure TCP and with autograft as positive control. MATERIALS AND METHODS: Four standardized bone defects were prepared in both mandibular angles of 16 minipigs and grafted with autogenous bone chips, HA, HA/TCP (60% : 40%), or TCP. Histologic and histomorphometric analysis of bone formation and graft degradation followed healing periods of 2, 4, 8, and 24 weeks. RESULTS: 2 weeks: more bone formation in defects filled with autograft than with the three CaP materials (P<0.05). 4 weeks: bone formation differed significantly (P<0.05) between all four materials (autograft>TCP>HA/TCP>HA). 8 weeks: more bone formation in defects with autograft and TCP than with HA/TCP (P<0.05), and HA/TCP had more bone formation than HA (P<0.05). 24 weeks: no difference in bone formation between the groups. Autograft and TCP resorbed quickly and almost completely over 8 weeks, whereas HA/TCP and HA showed limited degradation over 24 weeks. CONCLUSION: All defects healed with mature lamellar bone and intimate contact between bone and the remaining graft material. The rate of bone formation corresponded to the content of TCP in the CaP materials.

Bone healing and graft resorption of autograft, anorganic bovine bone and beta-tricalcium phosphate. A histologic and histomorphometric study in the mandibles of minipigs.

OBJECTIVE: The purpose was to qualitatively and quantitatively compare the bone formation and graft resorption of two different bone substitutes used in both orthopedic and oral surgery, with autogenous bone as a positive control. MATERIALS AND METHODS: Three standardized bone defects were prepared in both mandibular angles of 12 adult minipigs. The defects were grafted with either autograft, anorganic bovine bone (ABB), or synthetic beta-tricalcium phosphate (beta-TCP). Sacrifice was performed after 1, 2, 4, and 8 weeks for histologic and histomorphometric analysis. RESULTS: At 2 weeks, more new bone formation was seen in defects filled with autograft than with ABB (P approximately 0.0005) and beta-TCP (P approximately 0.002). After 4 weeks, there was no significant difference between beta-TCP and the two other materials. Defects grafted with ABB still exhibited less bone formation as compared with autograft (P approximately 0.004). At 8 weeks, more bone formation was observed in defects grafted with autograft (P approximately 0.003) and beta-TCP (P approximately 0.00004) than with ABB. No difference could be demonstrated between beta-TCP and autograft. beta-TCP resorbed almost completely over 8 weeks, whereas ABB remained stable. CONCLUSION: Both bone substitutes seemed to decelerate bone regeneration in the early healing phase as compared with autograft. All defects ultimately regenerated with newly formed bone and a developing bone marrow. The grafting materials showed complete osseous integration. Both bone substitutes may have a place in reconstructive surgery where different clinical indications require differences in biodegradability.

Treatment of severe atrophy of the maxilla with the prefabricated free vascularized fibula flap.

Treatment of severe maxillary atrophy despite complex major surgery often ends up with an unsatisfactory result. This paper presents the augmentation of the maxilla with a prefabricated free vascularized fibula flap in combination with ITI implants (Straumann AG, Waldenburg, Switzerland) in 4 patients. The technique of prefabrication for the reconstruction of maxillofacial defects is described based on the experience with 17 patients. The key points of this treatment are i) preoperative planning and fabrication of the drilling template; ii) prefabrication of the fibula with ITI implants and performing of a 'vestibuloplasty" using a skin graft; iii) technical construction and fabrication of the suprastructure and the denture; iv) reconstruction of the maxilla using the prefabricated fibula as free vascularized flap. The reconstructions with the fibula flaps were successful and the 18 ITI implants that have been inserted showed good osseointegration without loss of attachment in all 4 patients after a mean observation period of 12 months.