Erika Benavides

Teriparatide and osseous regeneration in the oral cavity

BACKGROUND Intermittent administration of teriparatide, a drug composed of the first 34 amino acids of parathyroid hormone, has anabolic effects on bone. Although teriparatide has been evaluated for the treatment of osteoporosis and for the healing of fractures, clinical trials evaluating it for the treatment of osseous conditions of the oral cavity in humans are lacking. METHODS A total of 40 patients with severe, chronic periodontitis underwent periodontal surgery and received daily injections of teriparatide (20 μg) or placebo, along with oral calcium (1000 mg) and vitamin D (800 IU) supplementation, for 6 weeks. The patients were followed for 1 year. The primary outcome was a radiographic linear measurement of alveolar bone level. Secondary outcomes included clinical variables, bone turnover markers in serum and oral fluid, systemic bone mineral density, and quality of life. RESULTS Radiographic linear resolution of osseous defects was significantly greater after teriparatide therapy than after placebo beginning at 6 months, with a mean linear gain in bone at 1 year of 29% as compared with 3% (P<0.001). Clinical improvement was greater in patients taking teriparatide than in those taking placebo, with a reduction in periodontal probing depth of 33% versus 20% (2.42 mm vs. 1.32 mm) and a gain in clinical attachment level of 22% versus 7% (1.58 mm vs. 0.42 mm) in target lesions at 1 year (P = 0.02 for both comparisons). No serious adverse events were reported; however, the number of patients in the study was small. No significant differences were noted with respect to the other variables that were assessed. CONCLUSIONS Teriparatide, as compared with placebo, was associated with improved clinical outcomes, greater resolution of alveolar bone defects, and accelerated osseous wound healing in the oral cavity. Teriparatide may offer therapeutic potential for localized bone defects in the jaw. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT00277706 .).

Use of cone beam computed tomography in implant dentistry: the International Congress of Oral Implantologists consensus report.

Purpose: The International Congress of Oral Implantologists has supported the development of this consensus report involving the use of Cone Beam Computed Tomography (CBCT) in implant dentistry with the intent of providing scientifically based guidance to clinicians regarding its use as an adjunct to traditional imaging modalities. Materials and Methods: The literature regarding CBCT and implant dentistry was systematically reviewed. A PubMed search that included studies published between January 1, 2000, and July 31, 2011, was conducted. Oral presentations, in conjunction with these studies, were given by Dr. Erika Benavides, Dr. Scott Ganz, Dr. James Mah, Dr. Myung-Jin Kim, and Dr. David Hatcher at a meeting of the International Congress of Oral Implantologists in Seoul, Korea, on October 6–8, 2011. Results: The studies published could be divided into four main groups: diagnostics, implant planning, surgical guidance, and postimplant evaluation. Conclusions: The literature supports the use of CBCT in dental implant treatment planning particularly in regards to linear measurements, three-dimensional evaluation of alveolar ridge topography, proximity to vital anatomical structures, and fabrication of surgical guides. Areas such as CBCT-derived bone density measurements, CBCT-aided surgical navigation, and postimplant CBCT artifacts need further research. ICOI Recommendations: All CBCT examinations, as all other radiographic examinations, must be justified on an individualized needs basis. The benefits to the patient for each CBCT scan must outweigh the potential risks. CBCT scans should not be taken without initially obtaining thorough medical and dental histories and performing a comprehensive clinical examination. CBCT should be considered as an imaging alternative in cases where the projected implant receptor or bone augmentation site(s) are suspect, and conventional radiography may not be able to assess the true regional three-dimensional anatomical presentation. The smallest possible field of view should be used, and the entire image volume should be interpreted.

AAE and AAOMR Joint Position Statement Use of Cone Beam Computed Tomography in Endodontics 2015 Update

The following statement was prepared by the Special Committee to Revise the Joint American Association of Endodontists/American Academy of Oral and Maxillofacial Radiology Position on Cone Beam Computed Tomography, and approved by the AAE Board of Directors and AAOMR Executive Council in May 2015. AAE members may reprint this position statement for distribution to patients or referring dentists.

The Impact of Vitamin D Status on Periodontal Surgery Outcomes

Vitamin D regulates calcium and immune function. While vitamin D deficiency has been associated with periodontitis, little information exists regarding its effect on wound healing and periodontal surgery outcomes. This longitudinal clinical trial assessed outcomes of periodontal surgery and teriparatide administration in vitamin-D-sufficient and -insufficient individuals. Forty individuals with severe chronic periodontitis received periodontal surgery, daily calcium and vitamin D supplements, and self-administered teriparatide or placebo for 6 wks to correspond with osseous healing time. Serum 25(OH)D was evaluated at baseline, 6 wks, and 6 mos post-surgery. Clinical and radiographic outcomes were evaluated over 1 yr. Placebo patients with baseline vitamin D deficiency [serum 25(OH)D, 16-19 ng/mL] had significantly less clinical attachment loss (CAL) gain (-0.43 mm vs. 0.92 mm, p < 0.01) and probing depth (PPD) reduction (0.43 mm vs. 1.83 mm, p < 0.01) than vitamin-D-sufficient individuals. Vitamin D levels had no significant impact on CAL and PPD improvements in teriparatide patients at 1 yr, but infrabony defect resolution was greater in teriparatide-treated vitamin-D-sufficient vs. -deficient individuals (2.05 mm vs. 0.87 mm, p = 0.03). Vitamin D deficiency at the time of periodontal surgery negatively affects treatment outcomes for up to 1 yr. Analysis of these data suggests that vitamin D status may be critical for post-surgical healing. (ClinicalTrials.gov number, CT00277706)

The Influence of the Bucco-Palatal Distance on Sinus Augmentation Outcomes

BACKGROUND Maxillary sinus augmentation is one of the most reliable implant site development options to increase vertical bone height. However, graft consolidation requires adequate angiogenesis and migration of cells involved in osteogenesis and bone remodeling. It is speculated that these biologic events are greatly determined by the dimensions of the maxillary sinus cavity. Hence, the purpose of this study is to assess the influence of the distance from the lateral to the medial wall of the maxillary sinus on the outcomes of sinus augmentation procedures. METHODS A total of 25 patients in need of sinus augmentation were recruited for the study. After initial examination, customized radiographic and surgical guides were fabricated and a cone-beam computerized tomography scan was obtained per patient. The bucco-palatal distance (BPD) was measured at 8, 10, and 12 mm from the alveolar crest. Sinus grafting was performed by a lateral window approach using a particulated allograft material. Patients were followed-up for 6 months. At the time of implant placement, bone core biopsies were harvested using the radiographic-surgical guide. Sections of the bone cores at 8, 10, and 12 mm from the alveolar crest were histomorphometrically analyzed. The proportion of vital bone (%VB) was correlated with the BPD using a statistical model. RESULTS Twenty-one patients underwent sinus augmentation for a total of 24 sinuses; however, the data analyzed contained only one sinus per patient. One sinus developed an infection after grafting, resulting in a 96% success rate for the sinus grafting procedure. Twenty sinuses were used in the final statistical analysis. Histomorphometric analysis revealed that mean %VB was 22.71 +/- 19.08, mean percent of remaining allograft was 23.39 +/- 20.85, and average percent of non-mineralized connective tissue was 53.90 +/- 13.23. Analysis of the correlation between %VB and BPD by linear regression, using the actual values of BPD showed a strong negative association (R(2) = 0.141; P <0.001). CONCLUSION The findings suggest that the %VB formation after maxillary sinus augmentation is inversely proportional to the sinus BPD.

Midpalatal suture maturation: classification method for individual assessment before rapid maxillary expansion.

INTRODUCTION In this study, we present a novel classification method for individual assessment of midpalatal suture morphology. METHODS Cone-beam computed tomography images from 140 subjects (ages, 5.6-58.4 years) were examined to define the radiographic stages of midpalatal suture maturation. Five stages of maturation of the midpalatal suture were identified and defined: stage A, straight high-density sutural line, with no or little interdigitation; stage B, scalloped appearance of the high-density sutural line; stage C, 2 parallel, scalloped, high-density lines that were close to each other, separated in some areas by small low-density spaces; stage D, fusion completed in the palatine bone, with no evidence of a suture; and stage E, fusion anteriorly in the maxilla. Intraexaminer and interexaminer agreements were evaluated by weighted kappa tests. RESULTS Stages A and B typically were observed up to 13 years of age, whereas stage C was noted primarily from 11 to 17 years but occasionally in younger and older age groups. Fusion of the palatine (stage D) and maxillary (stage E) regions of the midpalatal suture was completed after 11 years only in girls. From 14 to 17 years, 3 of 13 (23%) boys showed fusion only in the palatine bone (stage D). CONCLUSIONS This new classification method has the potential to avoid the side effects of rapid maxillary expansion failure or unnecessary surgically assisted rapid maxillary expansion for late adolescents and young adults.

Clinical and histologic outcomes after the use of a novel allograft for maxillary sinus augmentation: a case series.

Purpose:To document the clinical and histologic outcomes of sinus augmentation using a novel allogenic bone substitute as a sole grafting material. Materials:Patients in need of sinus augmentation before implant placement were recruited for this study. Sinus augmentation procedures were performed following a lateral approach, using a freeze-dried allograft as the only grafting material. Patients were followed up postoperatively for 6 months. Plaque score, wound healing, and patient discomfort were recorded at each follow-up visit. Implants were placed between 6 and 7 months after sinus augmentation and restored 6 months later. Bone core biopsy specimens were harvested at the time of implant placement and processed for histologic and histomorphometrical analysis. Vital bone, remaining allograft (RA) particles, and nonmineralized tissue percentages were assessed on each sample. Results were expressed as mean percentages with SD. Results:Of the 23 sinus patients, 20 patients underwent sinus augmentation surgery. All patients had satisfactory postoperative healing in the absence of complications. A total of 39 implants were placed. One implant failed and was replaced 3 months later. Histologic analysis revealed the presence of well-organized lamellar bone, in direct contact with RA particles. Mean vital bone was 23.02 ± 19.11%, mean RA was 22.25 ± 20.30%, and average nonmineralized tissue was 54.73 ± 13.51%. Conclusion:Clinical and histologic findings support the suitability of an allograft consisting of a combination of cortical and cancellous chips for sinus augmentation procedures.

Risk assessment of lingual plate perforation in posterior mandibular region: a virtual implant placement study using cone-beam computed tomography.

BACKGROUND Lingual plate perforation at the time of implant placement in posterior mandible is a potential surgical complication, and presence of a lingual concavity is considered a risk factor. Little is known about the spatial relationship between implant and lingual plate. The role of lingual concavity in the risk of lingual perforation has not yet been fully studied. This computer-simulated study investigates the incidence of lingual plate perforation in edentulous mandibular first molar region and the risk of perforation in the area of lingual concavity. METHODS One hundred and three qualified cone-beam computed tomography scans were selected from the database. Implants of various dimensions were virtually placed into the area using computer software. The distance between implant tip and lingual plate was measured using a digital caliper. Incidence of lingual plate perforation and proximity of the implant tip to lingual plate were measured for three types of cross-sectional mandibular morphology. RESULTS One hundred and three cone-beam computed tomography scans with 118 sites were available for analysis. The intraexaminer and interexaminer agreements were 0.93 and 0.89, respectively. The predicted incidence of lingual plate perforation was 1.1% to 1.2%. Most implants, which were within 1 mm from lingual plate, occurred in sites with lingual concavity (type-U ridge). CONCLUSIONS This study demonstrates a novel experimental design by which the spatial relation between implant and lingual plate in mandibular first molar region is investigated. Incidence of lingual plate perforation during implant placement is predicted to be 1.1% to 1.2% and it will most likely happen in type-U ridge.

3D osteoarthritic changes in TMJ condylar morphology correlates with specific systemic and local biomarkers of disease

OBJECTIVE To assess 3D morphological variations and local and systemic biomarker profiles in subjects with a diagnosis of temporomandibular joint osteoarthritis (TMJ OA). DESIGN Twenty-eight patients with long-term TMJ OA (39.9 ± 16 years), 12 patients at initial diagnosis of OA (47.4 ± 16.1 years), and 12 healthy controls (41.8 ± 12.2 years) were recruited. All patients were female and had cone beam CT scans taken. TMJ arthrocentesis and venipuncture were performed on 12 OA and 12 age-matched healthy controls. Serum and synovial fluid levels of 50 biomarkers of arthritic inflammation were quantified by protein microarrays. Shape Analysis MANCOVA tested statistical correlations between biomarker levels and variations in condylar morphology. RESULTS Compared with healthy controls, the OA average condyle was significantly smaller in all dimensions except its anterior surface, with areas indicative of bone resorption along the articular surface, particularly in the lateral pole. Synovial fluid levels of ANG, GDF15, TIMP-1, CXCL16, MMP-3 and MMP-7 were significantly correlated with bone apposition of the condylar anterior surface. Serum levels of ENA-78, MMP-3, PAI-1, VE-Cadherin, VEGF, GM-CSF, TGFβb1, IFNγg, TNFαa, IL-1αa, and IL-6 were significantly correlated with flattening of the lateral pole. Expression levels of ANG were significantly correlated with the articular morphology in healthy controls. CONCLUSIONS Bone resorption at the articular surface, particularly at the lateral pole was statistically significant at initial diagnosis of TMJ OA. Synovial fluid levels of ANG, GDF15, TIMP-1, CXCL16, MMP-3 and MMP-7 were correlated with bone apposition. Serum levels of ENA-78, MMP-3, PAI-1, VE-Cadherin, VEGF, GM-CSF, TGFβ1, IFNγ, TNFα, IL-1α, and IL-6 were correlated with bone resorption.

Regional 3D superimposition to assess temporomandibular joint condylar morphology

OBJECTIVES To investigate the reliability of regional three-dimensional registration and superimposition methods for assessment of temporomandibular joint condylar morphology across subjects and longitudinally. METHODS The sample consisted of cone beam CT scans of 36 patients. The across-subject comparisons included 12 controls, mean age 41.3 ± 12.0 years, and 12 patients with temporomandibular joint osteoarthritis, mean age 41.3 ± 14.7 years. The individual longitudinal assessments included 12 patients with temporomandibular joint osteoarthritis, mean age 37.8 ± 16.7 years, followed up at pre-operative jaw surgery, immediately after and one-year post-operative. Surface models of all condyles were constructed from the cone beam CT scans. Two previously calibrated observers independently performed all registration methods. A landmark-based approach was used for the registration of across-subject condylar models, and temporomandibular joint osteoarthritis vs control group differences were computed with shape analysis. A voxel-based approach was used for registration of longitudinal scans calculated x, y, z degrees of freedom for translation and rotation. Two-way random intraclass correlation coefficients tested the interobserver reliability. RESULTS Statistically significant differences between the control group and the osteoarthritis group were consistently located on the lateral and medial poles for both observers. The interobserver differences were ≤0.2 mm. For individual longitudinal comparisons, the mean interobserver differences were ≤0.6 mm in translation errors and 1.2° in rotation errors, with excellent reliability (intraclass correlation coefficient >0.75). CONCLUSIONS Condylar registration for across-subjects and longitudinal assessments is reliable and can be used to quantify subtle bony differences in the three-dimensional condylar morphology.