Effect of methylphenidate at different doses on new bone formation with rapid maxillary expansion: A micro-CT and histomorphometric study in rats.

OBJECTIVES: This study aimed to evaluate the effect of systemically administered methylphenidate hydrochloride (MPH) on new bone formation in premaxillary suture after rapid maxillary expansion (RME). SETTING AND SAMPLE POPULATION: Thirty-three Wistar rats were divided into four groups: Group 1 (high dose, 30/60 mg/kg MPH), Group 2 (low dose, 4/10 mg/kg MPH), Group 3 (positive control) and Group 4 (negative control). METHODS: RME was applied on the 70th day of the study. A 5-day RME period was followed by a 12-day retention period. The experiment was terminated on the 87th day. Micro-CT for radiological evaluation, haematoxylin-eosin and Masson's trichrome staining methods were used for histomorphometric evaluation. RESULTS: Among experimental groups with RME, the lowest number of osteoblasts and capillaries in Group 1 (P < .05). New bone formation, fibrous callus formation, distal osteotomy line, proximal osteotomy union and cortex remodelling were observed to be lower in Group 1 and Group 2 than Group 3 (P < .05). There was a statistically significant difference between Group 4 and each of the other groups (P = .000) in the evaluation of the results for bone mineral density, bone volume, bone volume percentage, trabecular thickness and trabecular number. CONCLUSIONS: MPH reduces cellular activity for new bone formation in suture in RME groups. Before performing rapid maxillary expansion in patients using MPH, the use of the drug should be postponed after a multidisciplinary decision process or clinical doses should be lowered.

Effect of revascularisation and apexification procedures on biomechanical behaviour of immature maxillary central incisor teeth: a three-dimensional finite element analysis study.

OBJECTIVES: This study aimed to assess the effects of revascularisation and apexification procedures on biomechanical behaviour of immature teeth using 3-dimensional finite element analysis (3D FEA). MATERIALS AND METHODS: Five 3D FEA permanent maxillary incisor models were developed from CBCT scans and available literature data: Model MT: Mature tooth, Model IT: Immature tooth (Cvek's stage 3), Model AT: Apexified tooth-mineral trioxide aggregate (MTA) apexification, Model RTB: Revascularised tooth with blood, and Model RTS: Revascularised tooth with supplementary scaffold. Using FEA, a masticatory load of 240N at 120° was simulated, and the Von Mises and maximum principal stresses within the models were evaluated. Failure index (FI) and weakening% were also calculated for each model. RESULTS: On dentinal stress analysis, model MT (96.16MPa) and IT (158.38MPa) had lowest and highest stress values, respectively. Among the experimental groups, model RTS (131.12MPa) had lower stresses than AT (136.33MPa) and RTB (133.7MPa), with no significant difference among the three. Peak dentinal stresses in all the models were observed in the cervical third of the root and near the apical opening in model IT. The extent of high dentinal stress area in model RTB and RTS was lesser than that of AT. The FI and weakening% values were highest for model AT followed by RTB and RTS, among the experimental groups. However, all these treatments strengthened an immature tooth by more than 20%. CONCLUSIONS: AT, RTB, and RTS treatments lowered the stress values and risk of fracture in immature teeth with no significant difference among the three groups. CLINICAL RELEVANCE: Stress distribution evaluation following revascularisation/apexification was essential, with potential to influence clinical decision-making. MTA apexification and revascularisation with blood clot/supplementary scaffold lowered the stresses in immature teeth, with no significant difference among the three.

970 nm low-level laser affects bone metabolism in orthodontic tooth movement.

OBJECTIVE: During orthodontic tooth movement (OTM), the speed of movement depends on the rate of bone turnover. In this study, we used a rat model to investigate the effect of 970 nm low-level laser therapy (LLLT) on OTM under different dose and frequency protocols. METHODS: We first compared the OTM rates between the OTM only control and the OTM + LLLT group (1250 J/cm2) in Experiment 1 and showed that LLLT significantly increased OTM. In Experiment 2, we employed 3 different LLLT protocols: the low-dose group and the high-dose group receiving 5 doses of 750 J/cm2 and 15,000 J/cm2 of LLLT every 3 days, respectively, and the early high-dose group which received 5 daily doses at 15,000 J/cm2 at the beginning of the experiments. The OTM-only control group received no LLLT. Tooth movement rate was measured through sequential silicone impressions. MicroCT was also performed to evaluate bone de-mineralization rate. Bone histmorphometry was used to compare the bone turnover rate between LLLT group and control group. Finally, TRAP, Osteocalcin, and VEGF expression is evaluated by immunohistochemistry (IHC) in tissue sections. RESULTS: When LLLT treatment was given every three days, both the 1250 J/cm2 and 15,000 J/cm2 groups showed significantly increased OTM compared to the control group. No significant difference was observed in the 750 J/cm2 group, or in the early irradiation group, when compared with controls, although 750 J/cm2 showed the same trend of accelerating OTM. The MicroCT result of rat maxilla demonstrated that LLLT increased bone remodeling and showed decreased bone mineral density and bone volume/total volume in the furcation areas of the maxillary first molars at the end of experiment. LLLT without OTM increased bone turnover as evidenced by fluorochrome incorporation. Immunohistochemistry analyses revealed high osteocalcin expression at later stages of OTM in the LLLT group, while VEGF expression was highly induced in the LLLT + OTM group at an early stage. CONCLUSION: Our results suggest that the 970 nm LLLT increases the rate of OTM in a dose-sensitive and frequency-dependent manner. Further animal and human studies are needed to determine the optimal timing and dosage of LLLT for OTM acceleration.

Osteo-regeneration personalized for children by rapid maxillary expansion: an imaging study based on synchrotron radiation microtomography.

BACKGROUND: Personalized maxillary expansion procedure has been proposed to correct maxillary transversal deficiency; different protocols of stem cell activation have been suggested and rapid maxillary expansion (RME) is the most commonly used among clinicians. The present study aimed to quantify in three-dimensions (3D) the osteo-regeneration of the midpalatal suture in children submitted to RME. METHODS: Three patients (mean age 8.3 ± 0.9 years) were enrolled in the study to preform biopsy of midpalatal suture. Two patients (subjects 1 and 2) were subjected to RME before biopsy. The third patient did not need maxillary expansion treatment and was enrolled as control (subject 3). Midpalatal suture samples were harvested 7 days after RME in subject 1, and 30 days after RME in subject 2. The samples were harvested with the clinical aim to remove bone for the supernumerary tooth extraction. When possible, maxillary suture and bone margins were both included in the sample. All the biopsies were evaluated by complementary imaging techniques, namely Synchrotron Radiation-based X-ray microtomography (microCT) and comparative light and electron microscopy. RESULTS: In agreement with microscopy, it was detected by microCT a relevant amount of newly formed bone both 7 days and 30 days after RME, with bone growth and a progressive mineralization, even if still immature respect to the control, also 30 days after RME. Interestingly, the microCT showed that the new bone was strongly connected and cross-linked, without a preferential orientation perpendicular to the suture's long axis (previously hypothesized by histology), but with well-organized and rather isotropic 3D trabeculae. CONCLUSIONS: The microCT imaging revealed, for the first time to the authors' knowledge, the 3D bone regeneration in children submitted to RME.

Effects of corticopuncture (CP) and low-level laser therapy (LLLT) on the rate of tooth movement and root resorption in rats using micro-CT evaluation.

The aim of this study was to compare the rate of tooth displacement, quantity of root resorption, and alveolar bone changes in five groups: corticopuncture (CP), low-level laser therapy (LLLT), CP combined with LLLT (CP + LLLT), control (C), and negative control (NC). A total of 60 half-maxilla from 30 male Wistar rats (10 weeks old) were divided randomly into five groups: three (CP, LLLT, and CP + LLLT) test groups with different stimulation for accelerated-tooth-movement (ATM), one control (C) group, and one negative control (NC) group with no tooth movement. Nickel-titanium coil springs with 50 g of force were tied from the upper left and right first molars to micro-implants placed behind the maxillary incisors. For the CP and CP + LLLT groups, two perforations in the palate and one mesially to the molars were performed. For the LLLT and CP + LLLT groups, GaAlAs diode laser was applied every other day for 14 days (810 nm, 100 mW, 15 s). The tooth displacements were measured directly from the rat's mouth and indirectly from microcomputer (micro-CT) tomographic images. Bone responses at the tension and compression sites and root resorption were analyzed from micro-CT images. The resulting alveolar bone responses were evaluated by measuring bone mineral density (BMD), bone volume fraction (BV/TV), and trabecular thickness (TbTh). Root resorption crater volumes were measured on both compression and tension sides of mesial and distal buccal roots. The tooth displacement in the CP + LLLT group was the greatest when measured clinically, followed by the CP, LLLT, and control groups (C and NC), respectively (p <0.05). The tooth movements measured from micro-CT images showed statistically higher displacement in the CP and CP + LLLT groups compared to the LLLT and control groups. The BMD, BV/TV, and TbTh values were lower at the compression side and higher at the tension side for all three test groups compared to the control group. The root resorption crater volume of the distal buccal root was higher in the control group, followed by CP, LLLT, and CP + LLLT, mostly at the compression site. Combining corticopuncture and low-level laser therapy (CP + LLLT) produced more tooth displacement and less root resorption at the compression side. The combined technique also promoted higher alveolar bone formation at the tension side.

Hyperbaric oxygen therapy for maxillary bone radiation-induced injury: A 15-year single-center experience.

BACKGROUND: Although hyperbaric oxygen therapy (HBOT) is used to treat chronic radiation tissue injury, clinical evidence supporting its use in maxillary bone osteoradionecrosis (ORN) is lacking. Therefore, the purpose of this study was to report our results of collected patient outcomes from a single center's large experience using HBOT to treat maxillary bone ORN. METHODS: From 1999 to 2015, 21 patients received treatment for maxillary bone ORN at our center. The medical records were retrospectively reviewed for the following variables: age, sex, comorbidities, tumor stage and site, previous surgery, previous radiotherapy or chemoradiation therapy, HBOT data, response to treatment and further management. RESULTS: A positive clinical outcome from HBOT occurred in 85.7% of patients with ORN and was proven radiologically in 14 of 15 patients (93.3%). In 5 patients, reconstructive surgery was required thereafter. CONCLUSION: Controversy exists regarding the management of ORN of the maxillofacial skeleton. Our large, single-center experience probably supports the efficacy of HBOT for maxillary bone ORN. © 2016 Wiley Periodicals, Inc. Head Neck 39: 275-278, 2017.

Bone augmentation at peri-implant dehiscence defects comparing a synthetic polyethylene glycol hydrogel matrix vs. standard guided bone regeneration techniques.

OBJECTIVES: The aim of the study was to test whether or not the use of a polyethylene glycol (PEG) hydrogel with or without the addition of an arginylglycylaspartic acid (RGD) sequence applied as a matrix in combination with hydroxyapatite/tricalciumphosphate (HA/TCP) results in similar peri-implant bone regeneration as traditional guided bone regeneration procedures. MATERIAL AND METHODS: In 12 beagle dogs, implant placement and peri-implant bone regeneration were performed 2 months after tooth extraction in the maxilla. Two standardized box-shaped defects were bilaterally created, and dental implants were placed in the center of the defects with a dehiscence of 4 mm. Four treatment modalities were randomly applied: i)HA/TCP mixed with a synthetic PEG hydrogel, ii)HA/TCP mixed with a synthetic PEG hydrogel supplemented with an RGD sequence, iii)HA/TCP covered with a native collagen membrane (CM), iv)and no bone augmentation (empty). After a healing period of 8 or 16 weeks, micro-CT and histological analyses were performed. RESULTS: Histomorphometric analysis revealed a greater relative augmented area for groups with bone augmentation (43.3%-53.9% at 8 weeks, 31.2%-42.8% at 16 weeks) compared to empty controls (22.9% at 8 weeks, 1.1% at 16 weeks). The median amount of newly formed bone was greatest in group CM at both time-points. Regarding the first bone-to-implant contact, CM was statistically significantly superior to all other groups at 8 weeks. CONCLUSIONS: Bone can partially be regenerated at peri-implant buccal dehiscence defects using traditional guided bone regeneration techniques. The use of a PEG hydrogel applied as a matrix mixed with a synthetic bone substitute material might lack a sufficient stability over time for this kind of defect.

Management of Self-Harm Injuries in the Maxillofacial Region: A Report of 2 Cases and Review of the Literature.

Clinicians face numerous challenges when managing psychiatric patients who self-inflict injuries within the maxillofacial region. In addition to a complex clinical examination, there are both surgical and psychiatric factors to consider, such as the risk of damaging vital structures, the exacerbation of the patient's psychiatric status, and the long-term psychosocial and esthetic sequelae. We present 2 cases of adolescents who repeatedly self-inflicted wounds and/or inserted foreign bodies (FBs) into the face, scalp, and neck. The different treatment modalities were based on full evaluation of the patient's clinical, medical, and diagnostic test findings coupled with a psychiatric assessment. The decision for conservative management or surgical intervention was made according to the presence and location of the FBs, degree of hemorrhage, signs and symptoms of infection, and unpleasant scars that could lead to long-term psychological impairment. In most cases, the FBs were removed and the wounds were toileted and closed under local or general anesthesia. We advocate a holistic approach via a multidisciplinary team, which is deemed essential to provide the highest quality of care for patients to reduce the risk of further relapses. Lastly, a satisfactory esthetic outcome is always paramount to achieve long-term psychological and physical welfare.

Rheumatoid Arthritis Exacerbates the Severity of Osteonecrosis of the Jaws (ONJ) in Mice. A Randomized, Prospective, Controlled Animal Study.

Rheumatoid arthritis (RA), an autoimmune inflammatory disorder, results in persistent synovitis with severe bone and cartilage destruction. Bisphosphonates (BPs) are often utilized in RA patients to reduce bone destruction and manage osteoporosis. However, BPs, especially at high doses, are associated with osteonecrosis of the jaw (ONJ). Here, utilizing previously published ONJ animal models, we are exploring interactions between RA and ONJ incidence and severity. DBA1/J mice were divided into four groups: control, zoledronic acid (ZA), collagen-induced arthritis (CIA), and CIA-ZA. Animals were pretreated with vehicle or ZA. Bovine collagen II emulsified in Freund's adjuvant was injected to induce arthritis (CIA) and the mandibular molar crowns were drilled to induce periapical disease. Vehicle or ZA treatment continued for 8 weeks. ONJ indices were measured by micro-CT (µCT) and histological examination of maxillae and mandibles. Arthritis development was assessed by visual scoring of paw swelling, and by µCT and histology of interphalangeal and knee joints. Maxillae and mandibles of control and CIA mice showed bone loss, periodontal ligament (PDL) space widening, lamina dura loss, and cortex thinning. ZA prevented these changes in both ZA and CIA-ZA groups. Epithelial to alveolar crest distance was increased in the control and CIA mice. This distance was preserved in ZA and CIA-ZA animals. Empty osteocytic lacunae and areas of osteonecrosis were present in ZA and CIA-ZA but more extensively in CIA-ZA animals, indicating more severe ONJ. CIA and CIA-ZA groups developed severe arthritis in the paws and knees. Interphalangeal and knee joints of CIA mice showed advanced bone destruction with cortical erosions and trabecular bone loss, and ZA treatment reduced these effects. Importantly, no osteonecrosis was noted adjacent to areas of articular inflammation in CIA-ZA mice. Our data suggest that ONJ burden was more pronounced in ZA treated CIA mice and that RA could be a risk factor for ONJ development. © 2016 American Society for Bone and Mineral Research.

[Multislice computed tomography in the diagnosis of toxic phosphorus necrosis of the jaw].

Objective: To estimate the possibilities of using and systematizing computed tomographic findings in patients with toxic phosphorus necrosis of the jaw. Material and Methods: The investigation enrolled 87 patients diagnosed as having toxic phosphorus osteonecrosis. Radiation examination consisted of two stages: primary and repeated radiologic examinations in the postoperative period (final examination before hospital discharge). All the patients underwent skull X-ray and multislice computed tomography (MSCT). Results: Clinical and radiation examination revealed toxic phosphorus osteonecrosis of the maxilla and mandible in 29 (33%) cases. Osteonecrosis affected only the mandible in 40 (46%) cases and only the maxilla in 18 (21%) cases. In all the patients, computed tomography showed main trends in the X-ray semiotics of toxic phosphorus necrosis of the facial skeleton, such as periostitis; osteosclerosis; development a lesion having a "soap-bubble" appearance; nonspecific and inflammatory bone destruction. The bone, being destroyed, was replaced by pus; inflammatory granulations were absent; osteonecrosis occurred. These processes were characterized by the absence of an obvious demarcation zone along the edges of the process. Sequestration commonly occurred to form sinus tracts. The process involved the adjacent bones; there were reactive changes in the accessory sinuses. Conclusion: MSCT data are of highly informative value in evaluating the status of bone tissue and teeth and in detecting a concomitant abnormality in patients with osteonecrosis of the facial skeleton and may be used to plan surgical treatment for this category of patients.

Supernumerary fourth molar and dental pathologies in a Chalcolithic individual from the El Mirador Cave site (Sierra de Atapuerca, Burgos, Spain).

We present a middle-aged Chalcolithic male with a supernumerary distomolar in the mandible. The prevalence of supernumerary teeth in present-day populations is low, ranging from 0.1% to 3.4%; most supernumerary teeth are documented in the anterior and molar regions of the maxilla in present populations. However, the prevalence of supernumerary molars in past populations is still unknown. Moreover, a complete pathological study has been done of this individual. Maxilla, mandible and teeth have been analyzed searching for dental pathologies. A cone-beam computed tomography (CBCT) analysis of mandibular and maxillary fragments was performed to check the evidence of hyperdontia. Dental wear and maxillary alveolar bone have been analyzed with environmental scanning electron microscope (ESEM) to improve the diagnosis of an abscess and evidence of tooth picking. This individual shows a left distomolar in the mandible without any evidence of other supernumerary teeth. The fourth molar is not associated with any congenital disease. However, this individual suffered severe dental wear and a variety of oral pathologies such as, dental decay, abscesses, pulpitis, periodontal disease, toothpicking marks in an upper molar, arthritis of the temporomandibular joint and malocclusion associated with high masticatory loads. To our knowledge, this individual from El Mirador Cave (Sierra de Atapuerca, Spain) shows the most ancient case of a fourth molar documented. The poor oral health of this individual corresponds to the general dental health of Chalcolithic populations.

An evaluation and comparison of the efficacy of nanocrystalline calcium sulfate bone grafts (NanoGen) and medical-grade calcium sulfate bone grafts (DentoGen) in human extraction sockets.

BACKGROUND: Grafting a fresh extraction socket is essential for successful regeneration of bone and maximizing volume preservation. Various synthetic grafts have been used to simulate bone formation. The purpose of the present study was to evaluate clinical, histomorphometric, and radiographic healing at 1-month, 3-month, and 4-month time points after tooth extraction with placement of calcium sulfate hemihydrate putty bone grafts NanoGen and DentoGen to determine their efficacy in ridge preservation following tooth extraction. METHOD: Sixty subjects who were in need of extraction were recruited. The subjects were randomly assigned their group based on computer software for both the test groups (NanoGen and DentoGen). DentoGen is a medical-grade calcium sulfate hemihydrate with particle of 30 µm, and NanoGen is a nanocrystalline version of DentoGen with particle size 400 µm to 800 µm. Data were recorded at 1, 3, and 4 months after extraction socket grafting. Bone biopsies were taken at 4 months for histomorphometric analysis. RESULTS: The mean percentage of bone formed by NanoGen was 51.19 ± 9.53% and by DentoGen 50.67 ± 16.16% after 4 months. No statistically significant difference was noted in the mean bone formation by NanoGen and DentoGen at various time intervals; no bone graft remnants of DentoGen were found at 4 months. The mean percentage of bone graft remnants left after 4 months for NanoGen was 6.83 ± 16% in the maxilla and 7.38 ± 21% in the mandible. The mean percentage of soft tissue formed was significantly higher with DentoGen in mandibular socket sites. On radiographic evaluation the mean percentage of socket fill with DenoGen was found to be 23.1 ± 11.65%, 50 ± 9.6%, and 76.7 ± 11% and with NanoGen was 29.2 ± 12.8%, 52.8 ± 15.6%, and 76.47 ± 12.43% at 1 month, 3 months, and 4 months postoperative intervals, respectively. CONCLUSION: Both the materials investigated in the study showed excellent bone forming capacity, but the nanocrystalline version (NanoGen) of calcium sulfate was found to have clinical and biologic advantages over DentoGen.

Three-dimensional analysis of maxillary anatomic landmarks for greater palatine nerve block anesthesia.

Greater palatine nerve block anesthesia (GPNBA) is a local anesthetic procedure used for maxillary and nasal treatment. Investigation of the three-dimensional anatomic location of the greater palatine foramen (GPF) is important for successful local anesthesia. The study aim was to provide standards for anatomic structures in the oral cavity that can be easily referred to in GPNBA. Maxillary computed tomography data were obtained from patients between 8 and 16 years of age whose maxillary incisors and first molars had already erupted (the growth group, n = 103); changes in the maxilla were observed over time in this group. Reference values for GPNBA in adults were measured in 107 patients older than 18 years. Maxillary computed tomography images were reconstructed three-dimensionally. Regression analysis demonstrates that all maxillary measurements in the growth group except for the distance from the posterior nasal spine to the GPF in the coronal plane correlated significantly with age. In adults, the mean perpendicular distance from the interdental alveolar bone between the left and right central incisors (1alvB) to the GPF in the coronal plane was 46.16 mm, and the mean distance from 1alvB to the GPF was 51.05 mm. The mean distance from the maxillary central incisor to the GPF was 57.58 mm. The mean angle between the line from the maxillary central incisor to each GPF and the sagittal plane was 16.49 degrees. The mean perpendicular distance from the anterior nasal spine to the GPF in the coronal plane was 43.49 mm, whereas the mean perpendicular distance from the GPF to the bone plane was 12.67 mm, and the mean perpendicular distance from the GPF to the occlusal plane was 22.13 mm. These measurements can be used to find the height of the GPF. In adults, the measured perpendicular distance from the incisive foramen to the GPF in the coronal plane was 32.04 mm, and the perpendicular distance from the median of the line that connects both of the contact points between the maxillary tuberosity and the pterygoid plate to the GPF in the coronal plane was 5.23 mm. Three-dimensional reference values relative to the anatomic structures in the oral cavity may increase the success rate of GPNBA and reduce complications. Although the maxillary growth pattern was analyzed, a limitation of this study is that maxillary anatomic measurements were not analyzed with regard to race or ethnicity.

Effect of a low-level laser on bone regeneration after rapid maxillary expansion.

INTRODUCTION: In this study, we evaluated the effects of a low-level laser on bone regeneration in rapid maxillary expansion procedures. METHODS: Twenty-seven children, aged 8 to 12 years, took part in the experiment, with a mean age of 10.2 years, divided into 2 groups: the laser group (n = 14), in which rapid maxillary expansion was performed in conjunction with laser use, and the no-laser group (n = 13), with rapid maxillary expansion only. The activation protocol of the expansion screw was 1 full turn on the first day and a half turn daily until achieving overcorrection. The laser type used was a laser diode (TWIN Laser; MMOptics, São Carlos, Brazil), according to the following protocol: 780 nm wavelength, 40 mW power, and 10 J/cm(2) density at 10 points located around the midpalatal suture. The application stages were 1 (days 1-5 of activation), 2 (at screw locking, on 3 consecutive days), 3, 4, and 5 (7, 14, and 21 days after stage 2). Occlusal radiographs of the maxilla were taken with the aid of an aluminum scale ruler as a densitometry reference at different times: T1 (initial), T2 (day of locking), T3 (3-5 days after T2), T4 (30 days after T3), and T5 (60 days after T4). The radiographs were digitized and submitted to imaging software (Image Tool; UTHSCSA, San Antonio, Tex) to measure the optic density of the previously selected areas. To perform the statistical test, analysis of covariance was used, with the time for the evaluated stage as the covariable. In all tests, a significance level of 5% (P <0.05) was adopted. RESULTS: From the evaluation of bone density, the results showed that the laser improved the opening of the midpalatal suture and accelerated the bone regeneration process. CONCLUSIONS: The low-level laser, associated with rapid maxillary expansion, provided efficient opening of the midpalatal suture and influenced the bone regeneration process of the suture, accelerating healing.

Morphological features of the maxillary incisors roots and relationship with neighbouring anatomical structures: possible implications in endodontic surgery.

The purpose of this study was to investigate the relationship between the root apex of the upper incisors and neighbouring anatomical structures as well as the morphology of the root-end foramen after apicoectomy. Fifty-seven patients requiring endodontic surgical treatment for a maxillary anterior root were enrolled. A preoperative diagnostic computed tomography (CT) scan was analysed to determine: the distance between the anterior wall of the nasopalatine duct and the central (CI-ND) incisor root 4mm from the apex; and the distance between the floor of the nasal cavity and the tip of either the central (CI-NF) or the lateral (LI-NF) incisor root. After apicoectomy, root-end foramen endoscopic pictures were taken in order to characterize their morphology. Fifty-nine central and 26 lateral incisors were evaluated. The average CI-ND was 4.71 ± 1.26 (SD) mm. The average CI-NF was 10.62 ± 2.25 mm. The average LI-NF was 13.05 ± 2.43 mm. The foramen shape after apicoectomy was ovoid to circular in about 90% of cases in both central and lateral incisors. A sound knowledge of the anatomical relationships at the surgical site is essential for the clinician to perform a safe endodontic surgical procedure.

Effect of low-level laser therapy (GaAlAs) on bone regeneration in midpalatal anterior suture after surgically assisted rapid maxillary expansion.

OBJECTIVE: The aim of this study was to evaluate the effects of laser therapy on bone regeneration in the midpalatal anterior suture (MPAS) after surgically assisted rapid maxillary expansion (SARME). METHODS: Thirteen patients aged between 18 and 33 years old with maxillary transverse deficiency (> or =7.0 mm) were evaluated. All patients underwent subtotal Le Fort I osteotomy with separation of the pterygomaxillary suture with the use of Hyrax expander, and were divided into 2 groups: control group (n = 6) and laser group (n = 7). A GaAlAs laser (P = 100 mW, lambda = 830 nm, Ø = 0.06 cm(2)) was used. The laser was applied in 8 treatment sessions with intervals of 48 hours. Each treatment session consisted of laser applications, per point (E = 8.4J, ED = 140J/cm(2)), at 3 points on the MPAS, and total dose of E = 25.2 J, ED = 420 J/cm(2). Digital radiographs were taken before the surgical procedure and at 1-, 2-, 3-, 4-, and 7-month follow-up visits. Optical density analysis of the regenerated bone was performed using Adobe Photoshop 8.0 software. RESULTS: Bone regeneration associated with the use of laser after SARME showed a statistically significant difference. A higher mineralization rate was found in the laser group (26.3%, P < .001) than the control group. CONCLUSION: Low-level laser irradiation (GaAlAs) accelerates bone regeneration in MPAS after SARME. However, the optical density measurements after 7 months of follow-up were lower in comparison with the preoperative measurements.

Bone quality associated with daily intake of coffee: a biochemical, radiographic and histometric study.

Caffeine induces loss of calcium and influences the normal development of bone. This study investigated the effects of coffee on bone metabolism in rats by biochemical measurement of calcium, bone densitometry and histometry. Male rats, born of female treated daily with coffee and with coffee intake since born, were anesthetized, subjected to extraction of the upper right incisor, and sacrificed 7, 21 and 42 days after surgery. Blood and urine samples were taken, and their maxilla radiographed and processed to obtain 5-µm-thick semi-serial sections stained with hematoxylin and eosin. The volume and bone quality were estimated using an image-analysis software. The results showed significantly greater amount of calcium in the plasma (9.40 ± 1.73 versus 9.80 ± 2.05 mg%) and urine (1.00 ± 0.50 versus 1.25 ± 0.70 mg/24 h) and significantly less amount in bone (90.0 ± 1.94 versus 86.0 ± 2.12 mg/mg bone), reduced bone mineral density (1.05 ± 0.11 versus 0.65 ± 0.15 mmAL), and lower amount of bone (76.19 ± 1.6 versus 53.41 ± 2.1 %) (ANOVA; p≤0.01) in animals treated with coffee sacrificed after 42 days. It may be concluded that coffee/caffeine intake caused serious adverse effects on calcium metabolism in rats, including increased levels of calcium in the urine and plasma, decreased bone mineral density and lower volume of bone, thus delaying the bone repair process.

Trial with Platelet-Rich Fibrin and Bio-Oss used as grafting materials in the treatment of the severe maxillar bone atrophy: clinical and radiological evaluations.

OBJECTIVES: The aim of the present study is to assess the implant osteointegration, as well as the course of bone regeneration and healing processes, thanks to the sinus lift procedure and by using PRF as a filling material, in association with the Bio-Oss. MATERIALS AND METHODS: 23 patients, requiring maxillary sinus lift in order to place implants into posterior maxillary region, were involved in this study. Selected cases, in which the height of the residual bone was superior to 5 mm, were adopted for surgical procedure of "one-stage sinus lift" (implant insertion concurrently occured with sinus lift resulting 6-9 months the healing and integration time). Before inserting the implant, a small quantity of filling material was placed in the cavity. For this purpose the bone fragment, stored in saline solution, was employed mixed with Bio-Oss and PRF, after being ground. RESULTS: All patients reported no pain to percussion, no sign of tissue suffering in the soft peri-implant tissues, the presence of an optimal primary stability of the inserted implants and a significant increase in the peri-implant bone density. CONCLUSIONS: In all cases included in this protocol, the Authors observed a successful implant-prosthetic rehabilitation, according with Albrektsson criteria.

The effects of hyperbaric oxygen on tooth movement into the regenerated area after distraction osteogenesis.

OBJECTIVE: To analyze the effect of hyperbaric oxygen on newly formed bone in distracted areas surrounding the root of a moving tooth by histological and radiological analysis. It was hypothesized that the application of hyperbaric oxygen to a tooth moving into the distracted area would accelerate ossification and vascularization of newly formed bone in the distracted space. DESIGN: Ten dogs were used. After creating a 10-mm-long bone defect, a bony segment was prepared and translocated into the defect area at a rate of 1 mm/d for 10 days. Following the distraction period, tooth movement was started and the dogs were divided into two groups. The HBO group received hyperbaric oxygen; whereas, the control group did not. At 150 days after tooth movement, the distracted area around the moving tooth was evaluated radiologically and histologically. Differences between groups were confirmed by a Mann-Whitney U test. RESULTS: Trabecular bone density and cortical and subcortical bone areas measured by peripheral quantitative computed tomography in the HBO group were significantly higher than those in the control group. Histological observations revealed regenerated bone and blood vessels formation in the tension site of the moving tooth in the HBO group. The regenerated bone structure measured by bone histomorphometry was larger and more active in bone formation in the HBO group than in the control group. CONCLUSIONS: Applying hyperbaric oxygen to tooth movement into a distracted area appears to accelerate ossification and vascularization of regenerated bone in the that area.

Sinus membrane lift using a water balloon followed by bone grafting and implant placement: a 28-case report.

PURPOSE: The objective of this study was to assess the efficacy and safety of a minimally invasive sinus lift using an inflatable water balloon followed by bone grafting and implant placement. MATERIALS AND METHODS: A total of 28 patients with a single tooth missing in the posterior maxilla underwent a water balloon sinus lift, followed by bone grafting and implant placement. Baseline bone height was 4.92 +/- 1.24 mm. Implant site preparation employed a pilot drill and osteotomy followed by water balloon elevation. The mean inflated balloon volume was 0.67 +/- 0.17 mL. Bio-Oss was filled under the elevated sinus membrane using a dedicated instrument. Twenty-eight total implants (diameter: 3.8 to 5.0 mm) were placed. Pre- and postoperative panoramic films or computed tomographs (optional) were taken for every case to measure and compare the results of the sinus membrane lift using a water balloon. Postoperative patient reactions including swelling, discoloration, discomfort, hematomas, and disability were recorded. RESULTS: Successful sinus membrane water balloon lifting procedures were performed in 26 cases; two procedures were aborted due to sinus membrane perforation. A total of 26 implants were placed. The mean inflated balloon volume was 0.67 +/- 0.17 mL and radiographic examination showed the mean elevated height by balloon to be 10.9 +/- 2.06 mm. Computed tomography showed the bone graft distributing evenly around implants. Patients were extremely pleased with the results and needed very little medical attention after surgery. The mean follow-up was 15.9 +/- 2.94 months. One implant was lost due to infection. CONCLUSION: The use of a water balloon to elevate the sinus membrane is a truly minimally invasive technique and is associated with very little discomfort. This method has encouraging results, is easy to learn, and is associated with low complication rates.