Showing papers in "Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology in 2008"

Comparative dosimetry of dental CBCT devices and 64-slice CT for oral and maxillofacial radiology

Abstract: Objectives This study compares 2 measures of effective dose, E1990 and E2007, for 8 dentoalveolar and maxillofacial cone-beam computerized tomography (CBCT) units and a 64-slice multidetector CT (MDCT) unit. Study design Average tissue-absorbed dose, equivalent dose, and effective dose were calculated using thermoluminescent dosimeter chips in a radiation analog dosimetry phantom. Effective doses were derived using 1990 and the superseding 2007 International Commission on Radiological Protection (ICRP) recommendations. Results Large-field of view (FOV) CBCT E2007 ranged from 68 to 1,073 μSv. Medium-FOV CBCT E2007 ranged from 69 to 560 μSv, whereas a similar-FOV MDCT produced 860 μSv. The E2007 calculations were 23% to 224% greater than E1990. Conclusions The 2007 recommendations of the ICRP, which include salivary glands, extrathoracic region, and oral mucosa in the calculation of effective dose, result in an upward reassessment of fatal cancer risk from oral and maxillofacial radiographic examinations. Dental CBCT can be recommended as a dose-sparing technique in comparison with alternative medical CT scans for common oral and maxillofacial radiographic imaging tasks.

Localization of impacted maxillary canines and observation of adjacent incisor resorption with cone-beam computed tomography.

Abstract: Objective The aim of this study was to investigate with cone-beam computed tomography (CBCT) the locations of impacted maxillary canines and resorption of neighboring incisors. Study design Two hundred ten impacted maxillary canines were analyzed using CBCT images. The locations of the impacted canines were assessed and angular and linear measurements were taken using NewTom proprietary software. In addition, root resorption of neighboring incisors was investigated. Results Among these impactions, 45.2% were impacted buccal-labially, 40.5% were impacted palatally, and 14.3% in the midalveolus. The locations varied: mesial-labial impaction (n = 67), mesial-palatal impaction (n = 74), in situ impaction (n = 31), distal impaction (n = 12), horizontal impaction (n = 18), and inverted impaction (n = 8). Quantitive measurements further depicted these variations. Root resorption was present in 27.2% of lateral and 23.4% of central incisors, and 94.3% of these resorptions occurred where the impacted canines were in close contact with the incisors. Conclusion The location of impacted maxillary canines varies greatly in 3 planes, and the resorption of neighboring permanent incisors is common.

A comparative study of histologic response to different pulp capping materials and a novel endodontic cement

Abstract: Objective The aim of this study was to compare dogs' pulp response to capping with calcium hydroxide cement (Dycal), mineral trioxide aggregate (MTA), and a novel endodontic cement (NEC). Study design Twenty-four canine teeth in 6 beagle dogs were buccocervically exposed and capped with MTA, Dycal, or NEC. Eight weeks later, retrieved samples were observed by optical microscope to grade inflammation, formation of dentinal bridge, calcification, necrosis, and presence of odontoblast cells. Results No inflammation was observed in MTA and NEC groups, and in 75% of each, dentinal bridge was completely formed. In the Dycal group, inflammation and incomplete dentinal bridge were detected in all cases. Although MTA and NEC groups had no significant difference between them in each measure, the difference between all 3 groups was significant (P Conclusion MTA and NEC showed similar favorable biologic response in pulp cap treatment, better than Dycal, especially in inducing the formation of dentinal bridge.

Comparative localized linear accuracy of small-field cone-beam CT and multislice CT for alveolar bone measurements.

Abstract: Objectives To compare the accuracy of cone-beam computerized tomography (CBCT) and multislice CT (MSCT) for linear jaw bone measurements. Study design An ex vivo formalin-fixed human maxilla was imaged with both CBCT (Accuitomo 3D; Morita, Kyoto, Japan) and MSCT (4-slice Somatom VolumeZoom and 16-slice Somatom Sensation 16; Siemens, Erlangen, Germany). The MSCT images were reconstructed using different reconstruction filters to optimize bone visualization (U70u and U90u for VolumeZoom, H30s and H60s for Sensation 16). Before scanning, triplets of small gutta-percha markers were glued onto the soft tissues overlying the maxillary bone on the top and on both sides of the alveolar ridge to define a set of reproducible linear measurements in 11 planes. Image measurements were performed by 2 observers. The gold standard was determined by means of physical measurements with a caliper by 3 observers. Results The accuracy of the linear measurements was 0.35 ± 1.31 mm (U70u) and 0.06 ± 1.23 mm (U90u) for the Somatom VolumeZoom, 0.24 ± 1.20 mm (H60s) and 0.54 ± 1.14 mm (H30s) for the Sensation 16, and −0.09 ± 1.64 mm for the Accuitomo 3D. Statistical analysis with 2-way analysis of variance showed no significant inter- or intraobserver disagreement for the physical or the radiologic measurements. There was also no significant difference for the measurements on the different reconstruction filters. Conclusion Both CBCT and MSCT yield submillimeter accuracy for linear measurements on an ex vivo specimen.

Bisphosphonate-associated jawbone osteonecrosis: a correlation between imaging techniques and histopathology

Abstract: Objectives Recently, jawbone osteonecrosis has been reported as a potential adverse effect of bisphosphonates administration. This paper considers and highlights histopathologic and radiologic features of this condition. Study design Eleven patients, owing to unresponsiveness to conservative treatment and uncontrollable pain, underwent surgical resection of diseased jawbone after extensive hyperbaric oxygen therapy. A thorough clinical, laboratory, and imaging study was performed. Surgical specimens underwent histopathologic and immunohistochemical evaluation. Results Computerized tomography (CT) scans showed increased bone density, periosteal reaction, and bone sequestration in advanced stages. With magnetic resonance imaging (MRI), exposed areas showed a low signal in T1- and T2-weighted and inversion recovery images, which suggests low water content and is histopathologically correlated with paucity in cells and vessels (osteonecrotic pattern). Unexposed diseased bone was characterized by T1 hypointensity and T2 and IR hyperintensity, which suggests high water content and inflammation, associated with hypercellularity, osteogenesis, and hypervascularity (osteomyelitic pattern). Conclusions Diseased bone extends beyond the limits of the bone exposed in the oral cavity. Histopathologic examination correlated well with CT and MRI, which are the choice for the evaluation of bisphosphonate-associated jawbone osteonecrosis.

Sinus augmentation using human mesenchymal stem cells loaded into a β-tricalcium phosphate/hydroxyapatite scaffold

Abstract: Objective Implant placement in the posterior maxilla may often be contraindicated because of insufficient bone volume and presence of the maxillary sinus. In these situations, sinus floor augmentation frequently has been proposed as the best treatment. This clinical study was based on the hypothesis that the clinical effectiveness of adult mesenchymal stem cells (MSCs) loaded to the biphasic scaffold. Methods In this report, the clinical and radiographic results are presented on 6 consecutively treated patients using MSCs in combination with biphasic hydroxyl apatite/ β-tricalcium phosphate (HA/TCP) for sinus elevation. All the patients in the study had less than 3 mm initial bone height in the posterior maxillary area (IBH). MSCs were cultured and expanded from bone marrow aspirate for each patient. Three months after sinus elevation, radiographic evaluation was performed for the patients and the secondary bone height was measured (SBH 1 ). In the second stage surgery, 30 implants were placed. Trephine bur was used as a pilot drill and a core biopsy was obtained from each implant site. Prosthetic rehabilitation of the patients was performed after 4 months. Secondary bone height was measured 9 months after implant placement (SBH 2 ). Results Of 30 implants, 28 (93%) were considered clinically successful. Two implants were removed due to mobility at the time of surgical exposure. Histologic evaluation of the biopsy specimens revealed numerous areas of osteoid and bone formation HA/TCP, with no evidence of inflammatory cell infiltrate. Mean bone regenerate was 41.34%. Clinically, no complications were observed, and all implants were considered clinically osseointegrated after 4 months. Mean bone height was measured 3 and 12 months after sinus grafting (mean of SBH 1 = 12.08 mm and mean of SBH 2 = 10.08 mm). Conclusions These clinical and histological findings suggest that sinus grafting with HA/TCP in combination with MSCs provide a viable therapeutic alternative for implant placement. The findings suggest that the addition of MSCs to bone derivative/substitute materials may enhance bone formation in the maxillary sinus area. Of course more studies with the control groups are needed for the evaluation of this method as a clinical solution for the patients.

Manufacturing splints for orthognathic surgery using a three-dimensional printer.

Abstract: Objective A new technique for producing splints for orthognathic surgery using a 3D printer is presented. Study design After 3-dimensional (3D) data acquisition by computerized tomography (CT) or cone-beam computerized tomography (CBCT) from patients with orthognathic deformations, it is possible to perform virtual repositioning of the jaws. To reduce artifacts, plaster models were scanned either simultaneously with the patient during the 3D data acquisition or separately using a surface scanner. Importing and combining these data into the preoperative planning situation allows the transformation of the planned repositioning and the ideal occlusion. Setting a virtual splint between the tooth rows makes it possible to encode the repositioning. After performing a boolean operation, tooth impressions are subtracted from the virtual splint. The “definitive” splint is then printed out by a 3D printer. Conclusion The presented technique combines the advantages of conventional plaster models, precise virtual 3D planning, and the possibility of transforming the acquired information into a dental splint.

American Academy of Oral and Maxillofacial Radiology executive opinion statement on performing and interpreting diagnostic cone beam computed tomography.

Abstract: The American Academy of Oral and Maxillofacial Radiology (AAOMR) is the professional organization representing oral and maxillofacial radiologists in the United States. The Academy is a nonprofit professional society the primary purposes of which are to advance the science of radiology, improve the quality and access of radiologic services to the patient, and encourage continuing education for oral and maxillofacial radiologists, dentists, and persons practicing oral and maxillofacial imaging in allied professional fields. The AAOMR embraces the introduction of cone beam computed tomography (CBCT) as a major advancement in the imaging armamentarium available to the dental profession. The AAOMR is currently in the process of developing a position paper on appropriate application of CBCT to provide evidence-based guidelines. In the interim, the Executive Committee (EC) of the AAOMR considers it necessary to provide an opinion document addressing the principles of application of CBCT as it relates to acquisition and interpretation of maxillofacial imaging in dental practice.

Oral non-Hodgkin's lymphoma : review of the literature and World Health Organization classification with reference to 40 cases

Abstract: Forty cases of oral cavity non-Hodgkin's lymphoma (NHL) were evaluated for sex, age, location, clinical presentation, and World Health Organization (WHO) histological subtype. Fifty-three percent were female and the mean age was 71. The upper jaw (maxilla or palatal bone), mandible, palatal soft tissue, and vestibule and gingivae (maxillary or mandibular soft tissue involvement only) were, respectively, the most common locations. Swelling, ulceration, and radiographic destruction of bone were the most frequent signs. Most of the lymphomas were of B cell lineage (98%), and the majority of these B cell lymphomas (58%) were histologically subtyped as diffuse large B cell lymphoma, which is considered to have an aggressive clinical course. An immunohistochemical panel was used in the majority of cases to confirm the lineage and to help characterize the subtype. B and T cell specific markers were used to show lineage of the neoplastic cells. Additional markers were used to help confirm specific subtypes that characteristically show specific positivity to some of these antibodies. Molecular studies to detect monoclonal immunoglobulin heavy chain (IgH) gene rearrangements and Bcl-1 and Bcl-2 gene translocations were performed in cases in which the diagnosis was in question. The current WHO classification is also reviewed in detail.

Influence of CBCT exposure conditions on radiation dose

Abstract: Background Cone-beam computed tomography (CBCT) has been changing the way dental practitioners use imaging. The radiation dose to the patient and how to effectively reduce the dose is still not completely clear to most users of this technology. Objective The objective of this study was to quantitate the change in radiation dose when using different CBCT settings. Methods A CBCT machine was modified to allow different setting combinations. The variables consisted of 4 different mA choices (2, 5, 10, and 15), 2 kVp choices (100 and 120), and 3 fields of view (6 inches, 9 inches, and 12 inches). A radiation phantom with 10 thermoluminescent dosimeters (TLD) was used to measure radiation dose. One specific setting (15 mA, 120 kVp, and 12-inch FOV) was scanned 3 times to determine consistency. Results The CBCT showed less than 5% variance in radiation dose values. An overall reduction in dose of about 0.62 times was achieved by reducing the kVp from 120 to 100. When reducing the field size the dose decreased 5% to 10%, while for organs that escaped the direct beam the reduction was far greater. Conclusions A reduction in radiation dose can be achieved by using the lowest exposure settings and narrow collimation.

Pigmented lesions of the oral mucosa and perioral tissues: a flow-chart for the diagnosis and some recommendations for the management.

Abstract: The term "pigmentation of the oral mucosa" is applied to a wide range of lesions or conditions featuring a change of color of oral tissues. Lesions not associated with an accumulation of pigment (e.g., Fordyce spots) are usually not classified as pigmented lesions. Two groups of pigmented lesions of the oral mucosa are recognized: 1) melanin-associated lesions, including racial pigmentations, melanotic macules, melanocytic nevi, and malignant melanoma; and 2) nonmelanin-associated lesions (e.g., blood-related pigmentations, metallic pigmentations). This paper presents a clinicopathologic review of the recent literature with emphasis on the main diagnostic features, including the use of immunohistochemical markers. A flow-chart is added that may help the clinician in the diagnosis and management of these lesions.

Low-level laser therapy for treatment of temporomandibular joint pain: a double-blind and placebo-controlled trial.

Abstract: Objective The objective of this study was to assess the effectiveness of low-level laser therapy (LLLT) in the management of temporomandibular joint (TMJ) pain in a random and double-blind research design. Study design TMJ pain patients, randomly assigned, received 2 to 3 treatments per week for 8 weeks of active LLLT (Helium Neon, 632.8 nm, 30 mW) (n = 26) or sham LLLT (n = 26). Measures of TMJ pain during function were evaluated at baseline and weeks 2, 4, and 8 after the first laser therapy. Results At the 8-week point, within-group improvements were present for TMJ pain during function, for both the active and sham LLLT groups (P = .000). Between-group differences were not highly evident (P > .05). Conclusion The study suggests that LLLT is not better than placebo at reducing TMJ pain during function.

Osteotome sinus floor elevation using Choukroun's platelet-rich fibrin as grafting material: a 1-year prospective pilot study with microthreaded implants.

Abstract: Objectives The aim of this prospective study was to document, radiographically, changes in the apical bone levels on microthreaded implants placed in subsinus residual bone height, according to a bone-added osteotome sinus floor elevation technique with platelet-rich fibrin (PRF) as grafting material. Study design Implants were placed using PRF as grafting material in the bone-added osteotome sinus floor elevation (BAOSFE) technique. The survival rate at abutment tightening (6 to 12 weeks of healing) and at 1 year was calculated. The radiographic analysis determined on consecutive radiographs: 1) the mean residual bone height (RBH) under the maxillary sinus at implant placement; and 2) the change in endosinus bone level. Mean and standard deviation were used to assess the endosinus bone changes in the mesial and distal implant sides at 1 year. Results Between December 2004 and June 2005, 20 consecutive patients were included in the study after bone height measurement by periapical radiographs. Patients included 14 women (70%) and 6 men (30%) with a mean age of 54.8 ± 11.1 years, range 35 to 73 years; they were treated with 35 Astra Tech implants (Astra Tech Dental Implant System; Astra Tech, Molndal, Sweden) fulfilling the inclusion criteria. The mean healing time before abutment tightening was 8.3 ± 1.4 weeks (range 6-12 weeks); by this time, 1 implant was mobile and was removed. At 1 year, all implants were clinically stable and the definitive prostheses were in function, resulting in a survival rate of 97.1%. Nineteen implants (55%) were 11 mm long, 6 implants (17%) were 9 mm, 5 implants (14%) were 8 mm, and 5 implants (14%) were 13 mm. The RBH was measured after implant placement on the radiographs on both implant sides. The mean RBH was 6.5 ± 1.7 mm: 6.3 ± 1.3 on the mesial side and 6.7 ± 2.0 mm on the distal side. Measurements of the changes in the endosinus level on the mesial and distal sides showed that all implants gained endosinus bone. The mean endosinus gain was 3.2 ± 1.5 mm: 3.5 ± 1.4 mm on the mesial side and 2.9 ± 1.6 mm on the distal side. The lowest bone gain was 0.9 mm and 0.1 mm on the mesial and distal sides, respectively. The highest gain was 5.8 mm and 5.2 mm on the mesial and distal sides, respectively. Conclusions The BAOSFE procedure with PRF as grafting material can lead to an endosinus bone gain. Despite a limited RBH, a healing period of 2-3 months was found to be sufficient to resist a torque of 25 N·cm applied during abutment tightening. At 1 year, formation of a new recognizable bone structure delimiting the sinus floor was identified radiologically and led to a predictable implant function.

Analysis of factors related to extraction of endodontically treated teeth.

Abstract: Background Endodontic therapy is a predictable treatment, resulting in up to 97% retention rate for the treated teeth. However, about 3% of endodontically treated teeth require further treatment, including extraction of the tooth. Study design This retrospective study analyzed all endodontically treated permanent teeth that were extracted in a multidisciplinary clinic in 2006-2007 (n = 547). Associations among the extractions' indications and the patients' gender, education, and smoking status, as well as tooth type and coronal restoration, were investigated. Results Of the 547 endodontically treated teeth that were subjected to extraction, mandibular (44.6%) and maxillary (20.5%) first molars were the most common. Fifteen percent of the extracted teeth were restored with a crown, whereas 57.4% of the extracted teeth did not have a permanent coronal restoration. The reasons for extraction were nonrestorable caries (61.4%), endodontic failure (12.1%), vertical root fracture (8.8%), iatrogenic perforation (8.8%), periodontal disease (4.6%), unrestorable cusp fracture (2.4%), orthodontic (1.3%), and prosthetic (0.2%) considerations and dental trauma (0.5%). Periodontitis was more prevalent among current smokers than among nonsmokers (P Conclusions The most common extracted tooth profile was the mandibular first molar without permanent coronal restoration, which was lost due to caries destruction. Endodontically treated teeth were prone to extraction mainly due to nonrestorable carious destruction and to a lesser extent to endodontic-related reasons such as endodontic failure, VRF, or iatrogenic perforation.

Assessments of trabecular bone density at implant sites on CT images.

Abstract: Objectives To evaluate the association between trabecular bone density measurements of potential implant sites made on axial DICOM images (DentaCT software) and on the same images with eFilm workstation, to correlate bone densities in Hounsfield units (HU) with subjective classification, and to establish a quantitative scale for each bone quality class. Study design Twenty-seven maxillary and 27 mandibular computed tomographic (CT) examinations of 75 potential implant sites were selected. Trabecular bone density was evaluated with DentaCT and eFilm. Bone quality was subjectively evaluated by 2 examiners. Descriptive statistics, between- and within-group comparison, correlation analysis, and Bland-Altman plot were used for data analysis. Results DentaCT measurements were higher than eFilm ( P 200 to 400 HU. Conclusion Different qualities of bone can be found in any of the anatomical regions studied (anterior and posterior sites of maxilla and mandible), which confirms the importance of a site-specific bone tissue evaluation prior to implant installation.

Marrow-derived mesenchymal stem cells-directed bone regeneration in the dog mandible: a comparison between biphasic calcium phosphate and natural bone mineral.

Abstract: Objective This study was designed to compare mesenchymal stem cell (MSC)-based alveolar bone regeneration in biphasic bone substitutes and natural bone mineral in a canine full-thickness alveolar defect model. Materials and methods MSCs were isolated from bone marrow aspirates and culture expanded through 3 successive subcultures. The bone differentiation potential of third passage cells was evaluated and confirmed in vitro before cells were used in the transplantation experiment. Undifferentiated cells were then incubated with 3 × 3 × 3 mm 3 hydroxyapatite/β-tricalcium phosphate (HA/TCP) matrices (Kasios, Lanauguet, France) and 1- to 2-mm Bio-Oss spongiosa (Geistlich Biomaterials, Osteohealth, Switzerland), which is a natural bovine bone mineral (NBM). Kasios/cell, Kasios alone, Bio-Oss/cell, and Bio-Oss alone were implanted in masseter muscle and 4 cylindrical (10-mm diameter) through-and-through bilateral mandibular body defects in 4 mongrel dogs. Histomorphometric analysis was performed 6 weeks after insertion of the scaffold loaded with MSCs. Results H&E staining of the decalcified scaffold and scanning electron microscopy demonstrated large MSC coverage of the HA/TCP and Bio-Oss. Cell-loaded Kasios matrices showed the greatest amount of the bone regeneration among the groups in both the muscle (29.11%) and the bone specimens (65.78%). Cell-free biphasic scaffold revealed 44.9% bone fill in bone defects and 23.55% in muscle specimen, and Bio-Oss alone matrices had the least amount of new bone formation: 36.84% and 24.16% in bone and muscle specimens respectively. Kasios loaded with MSCs demonstrated more bone regeneration than Bio-Oss/cell but there was no significant statistical difference ( P > .05). Conclusions New biphasic synthetic bone substitutes may offer better conditions for bone regeneration than traditional bone substitute in combination with MSCs. They remained in the defect and contributed to bone regeneration.

In Vivo Comparison of Conventional and Cone-Beam CT–Synthesized Cephalograms

Abstract: Objective: To compare measurements from synthesized cone-beam computed tomography (CBCT) lateral cephalograms using orthogonal and perspective projections with those from conventional cephalometric radiographs. Materials and Methods: Thirty-one patients were imaged using CBCT and conventional cephalometry. CBCT volume data were imported in Dolphin 3D. Orthogonal and perspective lateral cephalometric radiographs were created from three-dimensional (3D) virtual models. Twelve linear and five angular measurements were made on synthesized and conventional cephalograms in a randomized fashion. Conventional image measurements were corrected for known magnification. Linear and angular measurements were compared between image modalities using repeated measures analysis of variance. Statistical significance was defined as an α level of .01. Results: With the exception of the Frankfort-mandibular plane angle (P .01). Line...

Efficacy of He-Ne Laser in the prevention and treatment of radiotherapy-induced oral mucositis in oral cancer patients

Abstract: Objective The objective of this study was to evaluate the efficacy of low-level lasers for the prevention and treatment of radiotherapy-induced oral mucositis in oral cancer patients. Material and methods Twenty-four hospitalized patients with oral cancer, scheduled to undergo radiotherapy at KMC, Manipal, were enrolled in the present study and assigned to laser (Group I)/control group (Group II). They were treated using He-Ne laser (λ = 632.8nm, output = 10 mW and energy density = 1.8 J/cm 2 ). Patients were subjected to treatment using laser scanner for 8 days and subsequently were treated using laser probe at 6 anatomic sites in the oral cavity for 5 minutes each. The patients were evaluated on each day of treatment for pain severity (NRS), functional impairment (FIS), and oral mucositis (RTOG) and were followed until the end of cancer treatment. Statistical analysis was done using SPSS version 10. Results Laser therapy applied prophylactically during radiotherapy can reduce the severity of oral mucositis, severity of pain, and functional impairment.

Presence of arsenic in different types of MTA and white and gray Portland cement.

Abstract: Objective The presence of arsenic in various types of mineral trioxide aggregate (MTA) and Portland cements were evaluated to verify if they comply with the ISO-recommended limit for water-based cements of 2 mg arsenic/kg material. Study design An amount of 5 mL of hydrochloric acid was added to 2 g each of MTA and Portland cement to be analyzed. After 15 minutes, the material was filtered and the volume of supernatant was diluted with reagent-grade water up to 40 mL. Atomic absorption spectrophotometry readings were performed in triplicate. Results The following mean values were obtained: CPM (Egeo, Buenos Aires, Argentina) 11.06 mg/kg; CPM sealer (Egeo) 10.30 mg/kg; MTA-Obtura (Angelus, Londrina, PR, Brazil) 0.39 mg/kg; Experimental MTA: 10.30 mg/kg; White MTA-Angelus (Angelus) 1.03 mg/kg; Gray MTA-Angelus (Angelus) 5.91 mg/kg; ProRoot-MTA (Dentsply/Tulsa Dental Specialties, Tulsa, OK) 5.25 mg/kg; Gray Portland cement (Votorantim Cimentos, Cubatao, SP, Brazil): 34.27 mg/kg; and White Portland cement (Cimento Rio Branco, Rio de Janeiro, RJ, Brazil) 0.52 mg/kg. Conclusion All tested materials presented arsenic in their composition. The form of arsenic was not analyzed nor the toxicity of the arsenic found. Only MTA-Obtura, White MTA-Angelus, and White Portland cement presented arsenic levels below the limit set in the ISO 9917-1 standard.

A comparative CT evaluation of pharyngeal airway changes in class III patients receiving bimaxillary surgery or mandibular setback surgery

Abstract: Objective The purpose of this study was to compare the morphologic changes of the upper airway space in Class III patients who underwent mandibular setback or bimaxillary surgery (maxillary advancement and mandibular setback) by computed tomography at 2 levels: soft palate and base of tongue. Methods The sample consisted of 47 subjects in 2 groups who had been diagnosed as having Class III skeletal deformities and had been treated by mandibular setback or bimaxillary surgery (maxillary advancement and mandibular setback). Anteroposterior, lateral, and cross-sectional area dimensions of the airway at the level of soft palate and base of tongue were measured pre- and postoperatively on computed tomography images. Results Anteroposterior dimensions of the airway decreased in both groups ( P P P P > .05). Conclusions This study suggests that bimaxillary surgery can prevent narrowing of the upper airway in the correction of Class III deformities in comparison with mandibular setback surgery used as the sole treatment. Computed tomography was valuable in determining the effects of surgical treatment on pharyngeal airway dimensions.

Complications of maxillary sinus augmentations in a selective series of patients

Abstract: Objectives The purpose of this case series was to describe late complications of maxillary sinus augmentation procedures, including paranasal sinusitis and oroantral fistula, and to discuss the definitive surgical methods of treatment. Study design The case series included 13 patients hospitalized for a failed lateral-approach maxillary sinus augmentation, performed by a dental practitioner, with or without simultaneous implant placement. Data on patient gender and age, presenting signs and symptoms, radiographic appearance, method of repair, and follow-up were recorded. Results There were 7 female and 6 male patients aged 53-74 years. Twenty-six of the total 34 implants inserted failed, of which 7 were displaced into the sinus. All patients had maxillary sinusitis, and 2 also had an inflammation of other paranasal sinuses. Ten patients presented with an oroantral fistula. Review of the files of the referring practitioner revealed the preoperative presence of chronic maxillary sinusitis in 4 patients and an odontogenic cyst in 1. Caldwell-Luc operation served as the definitive surgical treatment. All fistulas were successfully closed by a palatal rotation advancement flap (8 patients) or a buccal flap (2 patients). Conclusions Thorough clinical and radiographic evaluation is necessary before sinus procedures to minimize complications. Total elimination of sinusitis and other pathologic conditions is recommended before maxillary sinus augmentation and implant surgery.

Oral mucosal lesions, microbial changes, and taste disturbances induced by adjuvant chemotherapy in breast cancer patients.

Abstract: Objective The aim of the study was to examine oral mucosal lesions, microbial changes, and taste disturbances induced by adjuvant chemotherapy (CT) in breast cancer patients during and 1 year after treatment. Study design Forty-five consecutive breast cancer patients, eligible for adjuvant CT with cyclophosphamide, epirubicin or methotrexate, and 5-fluorouracil were followed before, during, 6 months and 1 year after CT and were compared to a control group of 31 breast cancer patients not receiving adjuvant CT. Results During CT, oral mucosal lesions developed including erythema (n = 10, 22%) and ulceration (n = 7, 16%). Five patients (11%) were diagnosed with oral candidosis. Scores of dental bacterial plaque and gingival inflammation increased during CT and the oral microbial composition changed towards a more acidophilic flora. Taste disturbances were experienced by 84% (n = 38) of the patients in the CT group. Conclusion In breast cancer patients, moderate-intensive adjuvant CT caused oral mucosal lesions, oral candidosis, taste disturbances and a more acidophilic oral microflora. These adverse effects were temporary and the majority of the patients were mildly affected.

Mesenchymal stem cells enhance bone regeneration in rat calvarial critical size defects more than platelete-rich plasma.

Abstract: Objective The objective of this study was to compare culture-expanded bone marrow–derived mesenchymal stem cell and PRP loaded to natural bone mineral (Bio-Oss) and β-TCP for rat calvarial bone repair. Methods Twenty-two adult male Sprague-Dawley rats were randomly divided into 2 groups (n = 11). In the first group, 2 calvarial defects, 5 mm in diameter, were prepared in the parietal bone. The left defect was filled with Bio-Oss plus PRP while the right defect was filled with mesenchymal stem cell cultured on Bio-Oss. Kasios as a bone substitute was replaced in the second group. The animals were humanely killed 6 weeks postsurgery and the amount of the bone regeneration evaluated using histometric analysis. Result The bone fill length in the calvarial defect had statistically significant difference with other groups ( P Conclusions New synthetic bone substitutes may offer a better condition for bone regeneration compared to the traditional bone substitute in combination with mesenchymal stem cells. They remained in the defect and contributed bone regeneration. The use of the mesenchymal stem cell in conjunction with bone substitutes can enhance bone regeneration more than PRP.

Odontogenic tumors: a study of 250 cases in an Indian teaching hospital

Abstract: Objective Studies on odontogenic tumors published from many parts of the world show a distinct geographic variation. But there is little information available in the English-language literature on the relative frequency of odontogenic tumors in India. This retrospective study was designed to determine the relative frequency of odontogenic tumors in an Indian teaching hospital and compare them with various reports from other parts of the world. Study design The pathology records of the Department of Oral Pathology, Nair Hospital Dental College, from January 1971 to December 2006 were reviewed retrospectively, and based on World Health Organization classifications, 1992, we reclassified and analyzed the odontogenic tumors. The mandible and maxilla were divided into 7 anatomic regions, and the distribution of each odontogenic tumor among these regions was recorded and analyzed. Results A total of 250 cases of odontogenic tumors were reported in the 36-year period. Of these cases, 98.8% of the tumors were benign. The most frequent histologic type was ameloblastoma (61.5%), followed by adenomatoid odontogenic tumor (12.4%) and myxomas (6%). Odontomas, which are reported as the most frequent odontogenic tumor in American and European case reports, only accounted for 6%. In general, the odontogenic tumors showed a predilection for the mandible and the posterior regions of the jaws. Ameloblastomas occurred with a marked predilection for the mandible with a ratio of 18.1:1. But adenomatoid odontogenic tumor showed predilection for the maxilla, anterior regions of the jaws, and young females. Conclusions Odontogenic tumors show a definite geographic variation. In India, ameloblastoma and adenomatoid odontogenic tumor are the most frequent odontogenic tumors, with distinct anatomic predilections.

A quantitative analysis of coconut water: a new storage media for avulsed teeth.

Abstract: Objective The purpose of this study was to use a Collagenase-Dispase assay to investigate the potential of a new storage media, coconut water, in maintaining viable periodontal ligament (PDL) cells on simulated avulsed teeth. Study design Fifty freshly extracted human teeth were divided into 3 experimental groups and 2 control groups. The positive and negative controls corresponded to 0 minutes and an 8-hour dry time, respectively. The experimental teeth were stored dry for 30 minutes and then immersed in 1 of the 3 media: coconut water (CW), Hank’s balanced salt solution (HBSS), and milk. The teeth were then treated with Dispase grade II and Collagenase for 30 minutes. The number of viable PDL cells were counted with a hemocytometer and analyzed. Results Statistical analysis demonstrated that CW kept significantly more PDL cells viable compared to either HBSS or milk. Conclusion Within the parameters of this study, it appears that CW may be better alternative to HBSS or milk in terms of maintaining PDL cell viability after avulsion and storage.

Prevalence of commonly found pathoses associated with mandibular impacted third molars based on panoramic radiographs in Turkish population

Abstract: Objective The objective was to determine the association between commonly found pathologic conditions and angulations and impaction depths of lower third molar teeth. Study design In this retrospective study 1,914 panoramic radiographs with 3,050 impacted lower third molars (ILTMs) were examined. Results The problems and the prevalence evaluated were caries on mandibular second molar (12.6%), caries on ILTM (5.3%), bone loss at the distal aspect of ILTM (9.7%), and periodontal tissue damage on adjacent tooth (8.9%). A total of 26.5% of all the cases were affected by any one of the 4 pathologic changes. It was determined that horizontal and mesioangular ILTMs had high risk of caries development on second or third molar; in contrast, vertical and distoangular ILTMs had low risk. Distoangular and vertical ILTMs had high risk of development of bone loss at the distal aspect. Mesioangular and horizontal ILTMs had a high risk for periodontal tissue damage on an adjacent tooth. When evaluating impaction depth of the ILTM, class A had a higher risk of pathology than class B or C. Conclusions Horizontal and mesioangular impactions were found with more pathologic situations; especially in class A impaction depth. Angulation and impaction depth of the ILTM should be taken into consideration when making a decision whether to extract an ILTM or not.

Relationship between oral health status and development of osteoradionecrosis of the mandible: a retrospective longitudinal study.

Abstract: Objective Oral health status is a risk factor for postradiation bone complications (also known as osteoradionecrosis [ORN]), and oral health care is an important element in the prevention of this condition. Some authors recommend extracting teeth with a questionable prognosis and either gross mobility or periodontal disease. However, the criteria for making such decisions remain to be elucidated. In addition, the specific details of the association between oral health status and ORN have not yet been clearly demonstrated. The purpose of this study was to clarify the relationship between oral health status and the development of ORN. Study design Thirty-nine head and neck cancer patients whose radiation fields included both the teeth and the mandible were followed for ≥3 years after radiotherapy. Among these patients, 6 suffered from ORN (ORN group), and the other 33 did not experience the condition (non-ORN group). We analyzed the patient factors, radiation factors, and oral health factors related to the complication. Results The onset of ORN occurred from 18 months to 51 months after radiotherapy. The radiation dose in the oral cavity and the oral health status before radiotherapy were not significant risk factors for ORN. However, the oral health status at 1 year or 2 years after radiotherapy was significantly associated with the development of ORN. The oral health conditions that increased the risk of ORN were >5 mm periodontal pocket depth, >40% dental plaque score, >60% alveolar bone loss level, and a grade 3 radiographic periodontal status. Conclusion This is the first report to show the changes in the oral health status before and after radiotherapy regarding the development of ORN. The results support the periodontal status that almost all clinicians agree on as indications for preradiation teeth extraction (namely, periodontal pockets of >5 mm) to prevent ORN. Good oral health status, especially after radiotherapy, is very important in the prevention of ORN, and we recommend periodical dental management and care by well trained dentists and dental hygienists to avoid the condition.

Alveolar distraction osteogenesis versus inlay bone grafting in posterior mandibular atrophy: a prospective study

Abstract: Objective The objective of this study was to compare bone gain, implant survival, implant success, bone resorption, and complication rate in groups of patients who underwent distraction osteogenesis (DO) and inlay bone grafting (Inlay) for preprosthetic issues in the atrophic posterior mandible. Study design Twelve surgical sites were randomly assigned to 2 treatment groups: group A: DO and group B: Inlay. After 3 to 4 months, 16 fixtures in the DO group and 21 in the Inlay group were placed for fixed prosthetic rehabilitation. The median follow-up was 26 months. Results The median bone gain was 10 versus 5.8 mm (DO versus Inlay, P = .003); the median bone resorption was 1.4 mm versus 0.9 mm (DO versus Inlay, P = .088). The implant survival rate was 100% for each group, while the implant success rate was 93.7% (DO) versus 95.2% (Inlay) (P > .05). The complication rate was 60% for DO and 14.3% for Inlay (P < .05). Conclusion DO obtained more vertical bone gain than Inlay, but was more prone to complications in the pre-implantology phase. The implant results in each group were comparable to those in native alveolar bone.

Condylar positioning devices for orthognathic surgery: a literature review

Abstract: In the past few years, many devices have been proposed for preserving the preoperative position of the mandibular condyle during bilateral sagittal split osteotomy. Accurate mandibular condyle repositioning is considered important to obtain a stable skeletal and occlusal result, and to prevent the onset of temporomandibular disorders (TMD). Condylar positioning devices (CPDs) have led to longer operating times, the need to keep intermaxillary fixation as stable as possible during their application, and the need for precision in the construction of the splint or intraoperative wax bite. This study reviews the literature concerning the use of CPDs in orthognathic surgery since 1990 and their application to prevent skeletal instability and contain TMD since 1995. From the studies reviewed, we can conclude that there is no scientific evidence to support the routine use of CPDs in orthognathic surgery.

High-power diode laser in the disinfection in depth of the root canal dentin.

Abstract: Objective The objective of this study was to evaluate the disinfection degree of dentine caused by the use of diode laser after biomechanical procedures. Study design Thirty teeth were sectioned and roots were autoclaved and incubated for 4 weeks with a suspension of Enterococcus faecalis. The specimens were randomly divided into 3 groups (n = 10): G1, instrumented with rotary files, irrigated with 0.5% sodium hypochlorite and 17% EDTA-T, and then irradiated by 830-nm diode laser at 3 W; G2, the same procedures as G1 but without laser irradiation; and G3, irrigation with saline solution (control). Dentin samples of each third were collected with carbide burs and aliquots were sowed to count viable cells. Results The disinfection degree achieved was 100% in G1 and 98.39% in G2, when compared to the control group (G3). Conclusion Diode laser irradiation provided increased disinfection of the deep radicular dentin in the parameters and samples tested.