Penetration of flomoxef into human maxillary and mandibular bones.

Science.gov (United States)

Igawa, H H; Sugihara, T; Yoshida, T; Kawashima, K; Ohura, T

1995-09-01

Penetration of flomoxef into the maxillary and mandibular bones was assayed clinically to provide data about its usefulness for the prevention of postoperative infection after maxillofacial surgery. Twenty-one patients undergoing maxillofacial surgery at our department were given flomoxef 2 g dissolved in 20 ml of physiological saline intravenously over 3 minutes during operation, and the serum, maxillary and mandibular concentrations were measured 1, 3, and 6 hours after injection by the band culture method using Escherichia coli 7437 as the indicator strain. The mean concentrations were 53.4, 16.1, and 2.6 micrograms/ml, respectively, in the serum, 17.6, 7.8, and 1.0 micrograms/g in maxillary bone, and 16.4, 4.2, and 0.9 micrograms/g in mandibular bone. The mean bone:serum ratios at 1, 3, and 6 hours were 33.0%, 48.2%, and 36.8%, respectively, for maxillary bone, and 30.7%, 26.2%, and 35.7% for mandibular bone. When compared with previously reported data on the bone:serum ratios in jaw of various other intravenous antibiotics, our results show that penetration of flomoxef into maxillary and mandibular bone is extremely high. As all the intramaxillary and intramandibular concentrations exceed its MIC80 values against clinical isolates of bacteria frequently isolated in cases of infection in the oral and maxillofacial region, it is apparent that one intravenous shot of flomoxef 2 g allows penetration of the drug into the maxillary and mandibular bones at effective concentrations. Flomoxef is therefore potentially useful for the prevention and treatment of infections in the oral and maxillofacial region, as it has excellent penetration into the maxillary and mandibular bones.

Orthodontic treatment of an unerupted mandibular canine tooth in a patient with mixed dentition: a case report

OpenAIRE

Dinoi, Maria Teresa; Marchetti, Enrico; Garagiola, Umberto; Caruso, Silvia; Mummolo, Stefano; Marzo, Giuseppe

2016-01-01

Background The aim of this case report was to describe the surgical?orthodontic treatment of an unerupted mandibular canine tooth in a 9-year-old girl. Case presentation A 9-year-old white girl presented with an unerupted right mandibular canine tooth. Combined surgical?orthodontic treatment was performed to correct dental impaction and to achieve good aesthetic and functional results. Conclusion Orthodontic treatment achieved all of the required objectives.

Augmented mandibular bone structurally adapts to functional loading

NARCIS (Netherlands)

Verhoeven, J. W.; Ruijter, J. M.; Koole, R.; de Putter, C.; Terlou, M.; Cune, M. S.

2013-01-01

Long-term changes in trabecular bone structure during the 10 years following onlay grafting with simultaneous mandibular implant placement were studied. Extraoral radiographs of both mandibular sides in eight patients were taken regularly. Bone structure was analysed using a custom-written image

Influence of mastication and edentulism on mandibular bone density.

Science.gov (United States)

Chou, Hsuan-Yu; Satpute, Devesh; Müftü, Ali; Mukundan, Srinivasan; Müftü, Sinan

2015-01-01

The aim of this study was to demonstrate that external loading due to daily activities, including mastication, speech and involuntary open-close cycles of the jaw contributes to the internal architecture of the mandible. A bone remodelling algorithm that regulates the bone density as a function of stress and loading cycles is incorporated into finite element analysis. A three-dimensional computational model is constructed on the basis of computerised tomography (CT) images of a human mandible. Masticatory muscle activation involved during clenching is modelled by static analysis using linear optimisation. Other loading conditions are approximated by imposing mandibular flexure. The simulations predict that mandibular bone density distribution results in a tubular structure similar to what is observed in the CT images. Such bone architecture is known to provide the bone optimum strength to resist bending and torsion during mastication while reducing the bone mass. The remodelling algorithm is used to simulate the influence of edentulism on mandibular bone loss. It is shown that depending on the location and number of missing teeth, up to one-third of the mandibular bone mass can be lost due to lack of adequate mechanical stimulation.

Effect of implant position, angulation, and attachment height on peri-implant bone stress associated with mandibular two-implant overdentures: a finite element analysis.

Science.gov (United States)

Hong, Hae Ryong; Pae, Ahran; Kim, Yooseok; Paek, Janghyun; Kim, Hyeong-Seob; Kwon, Kung-Rock

2012-01-01

The aim of this study was to analyze and compare the level and distribution of peri-implant bone stresses associated with mandibular two-implant overdentures with different implant positions. Mathematical models of mandibles and overdentures were designed using finite element analysis software. Two intraosseous implants and ball attachment systems were placed in the interforaminal region. The overdenture, which was supported by the two implants, was designed to withstand bilateral and unilateral vertical masticatory loads (total 100 N). In all, eight types of models, which differed according to assigned implant positions, height of attachments, and angulation, were tested: MI (model with implants positioned in the lateral incisor sites), MC (implants in canine sites), MP (implants in premolar sites), MI-Hi (greater height of attachments), MC-M (canine implants placed with mesial inclination), MC-D (canine implants placed with distal inclination), MC-B (canine implants placed with buccal inclination), and MC-L (canine implants placed with lingual inclination). Peri-implant bone stress levels associated with overdentures retained by lateral incisor implants resulted in the lowest stress levels and the highest efficiency in distributing peri-implant stress. MI-Hi showed increased stress levels and decreased efficiency in stress distribution. As the implants were inclined, stress levels increased and the efficiency of stress distribution decreased. Among the inclined models, MC-B showed the lowest stress level and best efficiency in stress distribution. The lowest stress and the best stability of implants in mandibular two-implant overdentures were obtained when implants were inserted in lateral incisor areas with shorter attachments and were placed parallel to the long axes of the teeth.

Recurrent simple bone cyst of the mandibular condyle: a case report

Energy Technology Data Exchange (ETDEWEB)

Kim, Kyung A; Koh, Kwang Joon [Dept. of Oral and Maxillofacial Radiology, School of Dentistry, and Institute of Oral Bio Science, Chonbuk National University, Jeonju (Korea, Republic of)

2013-03-15

Cysts of the mandibular condyle are rare and can be difficult to diagnose and treat. Clinically, a simple bone cyst is asymptomatic and often discovered incidentally on routine radiographic examination. This report shows an atypical simple bone cyst occurring in the mandibular condyle showing recurrence after surgical curettage. Radiologically, this lesion involving the mandibular condyle should be distinguished from other similar lesions such as a chondriome, a central giant cell granuloma, and an aneurysmal bone cyst. Radiographic assessment was useful for forecasting the prognosis of a simple bone cyst. Possible reasons for the recurrence were discussed radiographically.

Distinct characteristics of mandibular bone collagen relative to long bone collagen: relevance to clinical dentistry.

Science.gov (United States)

Matsuura, Takashi; Tokutomi, Kentaro; Sasaki, Michiko; Katafuchi, Michitsuna; Mizumachi, Emiri; Sato, Hironobu

2014-01-01

Bone undergoes constant remodeling throughout life. The cellular and biochemical mechanisms of bone remodeling vary in a region-specific manner. There are a number of notable differences between the mandible and long bones, including developmental origin, osteogenic potential of mesenchymal stem cells, and the rate of bone turnover. Collagen, the most abundant matrix protein in bone, is responsible for determining the relative strength of particular bones. Posttranslational modifications of collagen, such as intermolecular crosslinking and lysine hydroxylation, are the most essential determinants of bone strength, although the amount of collagen is also important. In comparison to long bones, the mandible has greater collagen content, a lower amount of mature crosslinks, and a lower extent of lysine hydroxylation. The great abundance of immature crosslinks in mandibular collagen suggests that there is a lower rate of cross-link maturation. This means that mandibular collagen is relatively immature and thus more readily undergoes degradation and turnover. The greater rate of remodeling in mandibular collagen likely renders more flexibility to the bone and leaves it more suited to constant exercise. As reviewed here, it is important in clinical dentistry to understand the distinctive features of the bones of the jaw.

Distinct Characteristics of Mandibular Bone Collagen Relative to Long Bone Collagen: Relevance to Clinical Dentistry

Directory of Open Access Journals (Sweden)

Takashi Matsuura

2014-01-01

Full Text Available Bone undergoes constant remodeling throughout life. The cellular and biochemical mechanisms of bone remodeling vary in a region-specific manner. There are a number of notable differences between the mandible and long bones, including developmental origin, osteogenic potential of mesenchymal stem cells, and the rate of bone turnover. Collagen, the most abundant matrix protein in bone, is responsible for determining the relative strength of particular bones. Posttranslational modifications of collagen, such as intermolecular crosslinking and lysine hydroxylation, are the most essential determinants of bone strength, although the amount of collagen is also important. In comparison to long bones, the mandible has greater collagen content, a lower amount of mature crosslinks, and a lower extent of lysine hydroxylation. The great abundance of immature crosslinks in mandibular collagen suggests that there is a lower rate of cross-link maturation. This means that mandibular collagen is relatively immature and thus more readily undergoes degradation and turnover. The greater rate of remodeling in mandibular collagen likely renders more flexibility to the bone and leaves it more suited to constant exercise. As reviewed here, it is important in clinical dentistry to understand the distinctive features of the bones of the jaw.

Orthodontic management of buccally erupted ectopic canine with two case reports

Directory of Open Access Journals (Sweden)

Avesh Sachan

2012-01-01

Full Text Available Ectopic canine teeth develop displaced from their normal position. Any permanent tooth can be ectopic, and the cause may be both genetic and environmental. Orthodontic treatment is justified because ectopic canine teeth can migrate in the jaw bone and may damage the adjacent teeth roots and bone. Orthodontic treatment is also justifiable for aesthetic reasons. Diagnosis and treatment of ectopically erupting permanent maxillary canines requires timely management by the orthodontist. Internal or external root resorption of teeth adjacent to the ectopic canine is the most common sequel. Malocclusion with severe crowding is difficult to treat without extraction. Non-extraction treatment of ectopic canines can compromise the patient′s profile. This article represents two cases of extraction treatment approach for buccally displaced or ectopic canine in a patient with severe crowding in the mandibular arch.

Evaluation of dental age and associated developmental anomalies in subjects with impacted mandibular canines.

Science.gov (United States)

Jain, Shikha; Shetty, K Sadashiva; Jain, Shweta; Jain, Sachin; Prakash, A T; Agrawal, Mamta

2015-07-01

To assess the null hypothesis that there is no difference in the rate of dental development and the occurrence of selected developmental anomalies related to shape, number, structure, and position of teeth between subjects with impacted mandibular canines and those with normally erupted canines. Pretreatment records of 42 subjects diagnosed with mandibular canines impaction (impaction group: IG) were compared with those of 84 subjects serving as a control reference sample (control group: CG). Independent t-tests were used to compare mean dental ages between the groups. Intergroup differences in distribution of subjects based on the rate of dental development and occurrence of selected dental anomalies were assessed using χ(2) tests. Odds of late, normal, and early developers and various categories of developmental anomalies between the IG and the CG were evaluated in terms of odds ratios. Mean dental age for the IG was lower than that for the CG in general. Specifically, this was true for girls (P dental development and occurrence of positional anomalies also reached statistical significance (P anomalies compared with controls (odds ratios 3.00 and 2.82, respectively; P dental development compared with the female orthodontic patients. Increased frequency of positional developmental anomalies was also remarkable in the IG.

Bone changes of mandibular condyle using cone beam computed tomography

Energy Technology Data Exchange (ETDEWEB)

Lee, Ji Un; Kim, Hyung Seop; Song, Ju Seop; Kim, Kyoung A; Koh, Kwang Joon [Chonbuk National Univ., Chonju (Korea, Republic of)

2007-09-15

To assess bone changes of mandibular condyle using cone beam computed tomography (CBCT) in temporomandibualr disorder (TMD) patients. 314 temporomandibular joints (TMJs) images of 163 TMD patients were examined at the Department of Oral and Maxillofacial Radiology, Chonbuk National University. The images were obtained by PSR9000N (Asahi Roentgen Co., Japan) and reconstructed by using Asahivision software (Asahi Roentgen Co., Japan). The CBCT images were examined three times with four weeks interval by three radiologists. Bone changes of mandibular condyle such as flattening, sclerosis, erosion and osteophyte formation were observed in sagittal, axial, coronal and 3 dimensional images of the mandibular condyle. The statistical analysis was performed using SPSS 12.0. Intra-and interobserver agreement were performed by 3 radiologists without the knowledge of clinical information. Osteopathy (2.9%) was found more frequently on anterior surface of the mandibular condyle. Erosion (31.8%) was found more frequently on anterior surface of the mandibular condyle. The intraobserver agreement was good to excellent (k=0.78{sub 0}.84), but interobserver agreement was fair (k=0.45). CBCT can provide high qualified images of bone changes of the TMJ with axial, coronal and 3 dimensional images.

Bone changes of mandibular condyle using cone beam computed tomography

International Nuclear Information System (INIS)

Lee, Ji Un; Kim, Hyung Seop; Song, Ju Seop; Kim, Kyoung A; Koh, Kwang Joon

2007-01-01

To assess bone changes of mandibular condyle using cone beam computed tomography (CBCT) in temporomandibualr disorder (TMD) patients. 314 temporomandibular joints (TMJs) images of 163 TMD patients were examined at the Department of Oral and Maxillofacial Radiology, Chonbuk National University. The images were obtained by PSR9000N (Asahi Roentgen Co., Japan) and reconstructed by using Asahivision software (Asahi Roentgen Co., Japan). The CBCT images were examined three times with four weeks interval by three radiologists. Bone changes of mandibular condyle such as flattening, sclerosis, erosion and osteophyte formation were observed in sagittal, axial, coronal and 3 dimensional images of the mandibular condyle. The statistical analysis was performed using SPSS 12.0. Intra-and interobserver agreement were performed by 3 radiologists without the knowledge of clinical information. Osteopathy (2.9%) was found more frequently on anterior surface of the mandibular condyle. Erosion (31.8%) was found more frequently on anterior surface of the mandibular condyle. The intraobserver agreement was good to excellent (k=0.78 0 .84), but interobserver agreement was fair (k=0.45). CBCT can provide high qualified images of bone changes of the TMJ with axial, coronal and 3 dimensional images

Orthodontic-surgical treatment of four impacted canines in an adult patient: A case report.

Science.gov (United States)

Pavlović, Jasna; Tabaković, Saša Z; Simić, Sanja; Vujačić, Amila; Vukićević, Vladanka

2016-07-01

Full impaction of canines, in both jaws, is a rare phenomenon. It is usually coupled with the persistence of deciduous canines, or any other irregularity in the dental arch. Panoramic radiograph of a 24-year-old female patient showed bilateral canine impaction in both jaws. Due to vestibular, apical and medial position of canines in the upper jaw, the surgical approach implied the apically positioned flap technique. The position of impacted mandibular canines was vertical with more coronal position relative to the upper canines, thus requiring a closed eruption technique. Inadequate position of impacted canines in the bone fully justifies the use of orthodontic-surgical treatment.

A rare case of canine anomaly - a possible algorithm for treating it.

Science.gov (United States)

Vaida, Ligia; Todor, Bianca Ioana; Corega, Claudia; Băciuţ, Mihaela; Băciuţ, Grigore

2014-01-01

Canine transmigration is a very rare dental anomaly in which an unerupted mandibular canine migrates, crossing the mandibular midline. This unusual condition is most often diagnosed by chance during a routine X-ray examination. The most common clinical signs announcing the presence of this anomaly are over-retention of the deciduous canine and the absence of permanent canine from the dental arch after its physiological period of eruption. In this paper, we present a clinical case, 10-year-old boy, who was diagnosed with mandibular right canine transmigration at three years after the start of orthodontic treatment, during which we were expecting the eruption of mandibular canines. The orthopantomograph revealed the mandibular right canine to be in a horizontal position under the apices of the incisors - type 2 transmigration pattern classified by Mupparapu (2002). Based on cone-beam computer tomography examination, we recommended a surgical exposure of the canine and orthodontic alignment. Due to the risk of root resorption of the mandibular right lateral incisor during orthodontic movement phase of canine transmigrated to the dental arch, we decided to align the mandibular right canine in a transposition, between the two mandibular right incisors. Then we resorted to adapting the mandibular right lateral incisor coronary morphology to simulate a canine and also to reshaping the canine coronary morphology to resemble a lateral incisor. This therapeutic approach allowed us to restore morphologically and functionally the mandibular dento-alveolar arch, preserving the entire dental system.

Triple bone labeling of canine mandibles

DEFF Research Database (Denmark)

Pinholt, E M; Kwon, P H

1990-01-01

Fluorescence microscopy was used for evaluation of new bone formation in 16 canine mandibles augmented with hydroxylapatite (HA) granules. Three fluorochromes were injected at different time intervals during therapeutic radiation treatment. Oxytetracycline, DCAF, and alizarin-complexone were given...... intravenously to mark the bone level at these times, respectively. Oxytetracycline, which defined the baseline of bone at implantation of HA, was detectable in 42% of animals that were irradiated and in no animal of the nonirradiated control group. The marker DCAF, designating levels of bone at the start...

Orthodontic treatment for oral rehabilitation after multiple maxillofacial bone fractures.

Science.gov (United States)

Nakamura, Yoshiki; Ogino, Tomoko Kuroiwa; Hirashita, Ayao

2008-09-01

We present the orthodontic treatment of a patient with occlusal dysfunction after plastic surgery for multiple maxillofacial bone fractures caused by a traffic accident. The patient had mandibular deviation to the right because of inappropriate repositioning and fixation of the fractured bone and complete avulsion of both mandibular central incisors. The bilateral mandibular incisors, canines, and premolars were also suspected of partial avulsion or alveolar bone fracture. Several tests, including percussion and dental computed tomography, were performed on these teeth to rule out ankylosis and confirm tooth movement. Camouflage orthodontic treatment was carried out with expansion of the maxillary arch, alignment of both arches, and space closure between the mandibular lateral incisors to improve the occlusion. Good occlusion and interdigitation were obtained. Orthodontic treatment is useful for the rehabilitation of occlusal dysfunction caused by multiple maxillofacial bone fractures.

Mandibular incisive canal in relation to periapical surgery

Directory of Open Access Journals (Sweden)

Kani Bilginaylar

2016-01-01

Full Text Available The aim of the present paper is to emphasize the importance of the mandibular interforaminal neurovascular bundle with a case and make a warning to dentists and surgeons during oral and maxillofacial surgeries, such as implant replacement, bone harvesting, genioplasty, open reduction of a mandibular fracture, and cyst enucleations at this region. In this paper, we present a 58-year-old male who referred with pain and a tingling sensation on the left lower lip. After radiographical, extraoral and intraoral examinations, findings indicated the lesion to be a cyst which was related with a periapical lesion of the canine tooth and extracted socket of first premolar tooth. After removal of a cyst, the mandibular incisive nerve was documented which was in relation to cyst cavity.

Fusion of a primary mandibular lateral incisor and canine: A rarity

Directory of Open Access Journals (Sweden)

Treville Pereira

2017-01-01

Full Text Available Fusion is a developmental anomaly of dental hard tissues characterized by the union of two adjacent teeth. It may be complete with the formation of an abnormally large tooth or incomplete with the union of crowns or roots only. The exact cause is still unknown. This report describes a case of unilateral fusion of the primary lateral incisor and canine in a 6-year-old female patient who accompanied her parents for dental treatment and later had a checkup herself during one of the visits to the dental clinic. Medical history was noncontributory while there was no family history of dental anomalies. An intraoral examination revealed that mandibular right primary lateral incisor was fused to the primary canine. The permanent central incisors were erupting lingually. The intraoral periapical radiograph showed a bifid pulp chamber with a normal-sized root canal. Since the tooth was noncarious, a preventive approach with a periodic follow-up was planned.

Repair of a mandibular defect with a free vascularized coccygeal vertebra transfer in a dog.

Science.gov (United States)

Yeh, L S; Hou, S M

1994-01-01

Bilateral mandibular defects in a male mongrel dog were repaired. On the left side, a free vascularized coccygeal bone graft that included the median caudal artery and caudal vein was used to correct the defect. On the right side, the defect was bridged with a bone plate and screws. For further immobilization, the muzzle was temporarily taped for 3 weeks and a pharyngostomy tube was used for nutritional support. The dog was able to eat dry commercial food satisfactorily within 2 months of surgery despite mild malocclusion. Radiographs taken 2 months and 18 months postoperatively showed bony union with graft hypertrophy in the left mandible, whereas the right mandibular defect showed protracted nonunion. The results indicate that vascularized coccygeal vertebra transfer provides an alternative for the management of canine mandibular defects.

Ultrasound stimulation of mandibular bone defect healing

NARCIS (Netherlands)

Schortinghuis, Jurjen

2004-01-01

The conclusions of the experimental work presented in this thesis are: 1. Low intensity pulsed ultrasound is not effective in stimulating bone growth into a rat mandibular defect, either with or without the use of osteoconductive membranes. 2. Low intensity pulsed ultrasound does not seem to have an

Circumferential bone loss around splinted and nonsplinted immediately loaded implants retaining mandibular overdentures: A randomized controlled clinical trial using cone beam computed tomography.

Science.gov (United States)

Elsyad, Moustafa Abdou; Khirallah, Ahmed Samir

2016-11-01

Circumferential marginal bone around 2 splinted and nonsplinted immediately loaded implants in the edentulous mandible has not been previously investigated. The purpose of this randomized controlled clinical trial was to assess circumferential bone loss around splinted and nonsplinted immediately loaded implants retaining mandibular overdentures, using cone beam computed tomography (CBCT). Thirty participants with complete edentulism were allocated to 2 groups and received 2 implants in the canine region of the mandible. Implants were either left nonsplinted (with ball attachment [BA]) or splinted (with bar attachment [RA]). Mandibular overdentures were connected to the implants 1 week later. CBCT was used to evaluate vertical bone loss (VBL) and horizontal bone loss (HBLo) bone loss at the distal (D), buccal (B), mesial (M), and lingual (L) sites of each implant upon overdenture insertion (baseline, T0), 1 year (T1) and 3 years (T3) after insertion. Repeated measures ANOVA was used for statistical analysis (α=.05). No significant difference in the survival rate (93.3% for BA and 100% for RA) was found between groups (P=.156). VBL and HBLo increased significantly at T3 compared with T1 for both groups (Poverdentures were associated with significantly higher vertical and horizontal circumferential bone loss than those associated with splinted implants after a follow-up of 3 years. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Quantitation of mandibular ramus volume as a source of bone grafting.

Science.gov (United States)

Verdugo, Fernando; Simonian, Krikor; Smith McDonald, Roberto; Nowzari, Hessam

2009-10-01

When alveolar atrophy impairs dental implant placement, ridge augmentation using mandibular ramus graft may be considered. In live patients, however, an accurate calculation of the amount of bone that can be safely harvested from the ramus has not been reported. The use of a software program to perform these calculations can aid in preventing surgical complications. The aim of the present study was to intra-surgically quantify the volume of the ramus bone graft that can be safely harvested in live patients, and compare it to presurgical computerized tomographic calculations. The AutoCAD software program quantified ramus bone graft in 40 consecutive patients from computerized tomographies. Direct intra-surgical measurements were recorded thereafter and compared to software data (n = 10). In these 10 patients, the bone volume was also measured at the recipient sites 6 months post-sinus augmentation. The mandibular second and third molar areas provided the thickest cortical graft averaging 2.8 +/- 0.6 mm. The thinnest bone was immediately posterior to the third molar (1.9 +/- 0.3 mm). The volume of ramus bone graft measured by AutoCAD averaged 0.8 mL (standard deviation [SD] 0.2 mL, range: 0.4-1.2 mL). The volume of bone graft measured intra-surgically averaged 2.5 mL (SD 0.4 mL, range: 1.8-3.0 mL). The difference between the two measurement methods was significant (p AutoCAD software program did not overestimate the volume of bone that can be safely harvested from the mandibular ramus.

Orthodontic traction of a transmigrated mandibular canine using mini-implant: a case report and review.

Science.gov (United States)

Plaza, Sonia Patricia

2016-12-01

The patient in this case is an 11-year-old girl, whose mandibular left canine was transmigrated. The traction to the arch was assisted by using a temporary skeletal anchorage device. After 5 months of poor response to traction, the biomechanics were re-adjusted, obtaining effective traction in to the arch in 12 months. After this period, the treatment was completed with fixed orthodontic appliances.

The effect of intraosseous local anesthesia of 4% articaine with 1:100,000 epinephrine on pulpal blood flow and pulpal anesthesia of mandibular molars and canines.

Science.gov (United States)

Vongsavan, Kadkao; Samdrup, Tshering; Kijsamanmith, Kanittha; Rirattanapong, Praphasri; Vongsavan, Noppakun

2018-05-10

The aim of this study was to determine the effect of intraosseous (IO) anesthesia with 4% articaine and 1:100,000 epinephrine on pulpal blood flow (PBF) and pulpal anesthesia of mandibular first molars and canines in human subjects. Ten healthy volunteers with intact mandibular first molar and canine were given an osteocentral technique of IO injection using the Quick Sleeper 5 system and 4% articaine with 1:100,000 epinephrine at distal site of mandibular first molar. The PBF was monitored by a laser Doppler flowmeter (LDF). Pulpal anesthesia was assessed with an electric pulp tester (EPT). IO injection caused a decrease in PBF in molars from 6.31 ± 3.85 perfusion units (P.U.) before injection to 2.51 ± 2.53 P.U. 1 min after injection (P anesthesia in the molars, the mean onset was 2.40 ± 0.84 min and the mean duration was 38 ± 16.19 min. In the canines, there was a decrease in the sensitivity to EPT but complete pulpal anesthesia was not achieved. IO injection distal to mandibular first molar caused a decrease in PBF and successful pulpal anesthesia in first molar, but not in canine. Both PBF and EPT readings returned to normal, suggesting that pulpal ischemia may not occur. IO anesthesia is safe to use as a primary technique in teeth with normal pulp.

Assessment of vascularity in irradiated and nonirradiated maxillary and mandibular minipig alveolar bone using laser doppler flowmetry.

NARCIS (Netherlands)

Verdonck, H.W.; Meijer, G.J.; Laurin, T.; Nieman, F.H.; Stoll, C.; Riediger, D.; Stoelinga, P.J.W.; Baat, C. de

2007-01-01

PURPOSE: The purpose of this animal study was to confirm that laser Doppler flowmetry (LDF) is a reproducible method for the assessment of maxillary and mandibular alveolar bone vascularity and that there is less vascularity in irradiated mandibular and maxillary bone compared to nonirradiated bone.

A case of osteomyelitis of mandibular bone in Kimura's disease

Energy Technology Data Exchange (ETDEWEB)

Kinugawa, Hiroshi; Shimada, Fumihiko; Sai, Yoshikazu; Amakata, Yoshikuni; Yoshitake, Kazusada [Shiga Univ. of Medical Science, Otsu (Japan)

1991-07-01

We experienced a case of osteomyelitis of mandibular bone in Kimura's disease. The patient received radiation therapy to head and neck area against the same disease. Bone tissue which received radiation therapy had developed malnutrition as side effect of radiation, and osteomyelitis was induced by infection from the teeth. Even in the benign soft tissue disease like Kimura's disease, especially after radiation therapy, pathologic fracture of bone may happen due to bone damage caused by radiation. (author).

Long-term effectiveness of canine-to-canine bonded flexible spiral wire lingual retainers

NARCIS (Netherlands)

Renkema, Anne-Marie; Renkema, Alianne; Bronkhorst, Ewald; Katsaros, Christos

Introduction: The flexible spiral wire (FSW) canine-to-canine lingual retainer bonded to all 6 anterior teeth is a frequently used type of mandibular fixed retainer. This study aimed to assess the long-term effectiveness of FSW canine-to-canine lingual retainers in maintaining the alignment of the

Long-term effectiveness of canine-to-canine bonded flexible spiral wire lingual retainers

NARCIS (Netherlands)

Renkema, A.M.; Bronkhorst, E.M.; Katsaros, C.

2011-01-01

INTRODUCTION: The flexible spiral wire (FSW) canine-to-canine lingual retainer bonded to all 6 anterior teeth is a frequently used type of mandibular fixed retainer. This study aimed to assess the long-term effectiveness of FSW canine-to-canine lingual retainers in maintaining the alignment of the

The relationship between age and the mandibular cortical bone thickness by using panoramic radiograph

International Nuclear Information System (INIS)

Kim, Yun Suk; Kim, Kyoung A; Koh, Kwang Joon

2010-01-01

This study was to determine the relationship between age and the mandibular cortical bone thickness on panoramic radiograph. Panoramic radiographs of 360 patients (180 men and 180 women) over 20 years old, who visited the Chonbuk National University Hospital from January to December in 2007, were assessed. The subjects were divided into 5 age groups. Five indices such as cortical bone thickness at the gonion (GI), antegonion (AI), and below the mental foramen (MI), the panoramic mandibular index (PMI), the mandibular cortical index (MCI) were measured on panoramic radiographs. All five indices including GI, AI, MI, PMI, and MCI showed significant differences between third decade and over 8 decade groups (p,0.05). PMI, MI and GI showed significant differences with gender statistically (p<0.05). The mandibular cortical bone thickness showed negative correlation with age, and the value of the thickness (PMI, MI, and GI) was greater in men than in women.

Influence of Implant Positions and Occlusal Forces on Peri-Implant Bone Stress in Mandibular Two-Implant Overdentures: A 3-Dimensional Finite Element Analysis.

Science.gov (United States)

Alvarez-Arenal, Angel; Gonzalez-Gonzalez, Ignacio; deLlanos-Lanchares, Hector; Brizuela-Velasco, Aritza; Dds, Elena Martin-Fernandez; Ellacuria-Echebarria, Joseba

2017-12-01

The aim of this study was to evaluate and compare the bone stress around implants in mandibular 2-implant overdentures depending on the implant location and different loading conditions. Four 3-dimensional finite element models simulating a mandibular 2-implant overdenture and a Locator attachment system were designed. The implants were located at the lateral incisor, canine, second premolar, and crossed-implant levels. A 150 N unilateral and bilateral vertical load of different location was applied, as was 40 N when combined with midline load. Data for von Mises stress were produced numerically, color coded, and compared between the models for peri-implant bone and loading conditions. With unilateral loading, in all 4 models much higher peri-implant bone stress values were recorded on the load side compared with the no-load side, while with bilateral occlusal loading, the stress distribution was similar on both sides. In all models, the posterior unilateral load showed the highest stress, which decreased as the load was applied more mesially. In general, the best biomechanical environment in the peri-implant bone was found in the model with implants at premolar level. In the crossed-implant model, the load side greatly altered the biomechanical environment. Overall, the overdenture with implants at second premolar level should be the chosen design, regardless of where the load is applied. The occlusal loading application site influences the bone stress around the implant. Bilateral occlusal loading distributes the peri-implant bone stress symmetrically, while unilateral loading increases it greatly on the load side, no matter where the implants are located.

Reconstruction of mandibular defects with autogenous bone grafts: a review of 30 cases

International Nuclear Information System (INIS)

Sajid, M.A.; Warraich, R.A.; Abid, H.; Haq, M.E.; Shah, K.L.; Khan, Z.

2012-01-01

Multitudes of options are available for reconstruction of functional and cosmetic defects of the mandible, caused by various ailments. At the present time, autogenous bone grafting is the gold standard by which all other techniques of reconstruction of the mandible can be judged. The purpose of this study was to evaluate the outcome of different osseous reconstruction options using autogenous bone grafts for mandibular reconstruction. Methods: This Interventional study was conducted at Department of Oral and Maxillofacial Surgery, King Edward Medical University/Mayo Hospital Lahore, from January 2008 to July 2009 including one year follow-up. The study was carried out on thirty patients having bony mandibular defects. They were reconstructed with the autogenous bone grafts from different graft donor sites. On post-operative visits they were evaluated for outcome variables. Results: Success rate of autogenous bone grafts in this study was 90%. Only 10% of the cases showed poor results regarding infection, resorption and graft failure. Conclusion: Autogenous bone grafts, non-vascularized or vascularized, are a reliable treatment modality for the reconstruction of the bony mandibular defects with predictable functional and aesthetic outcome. (author)

Collagenases and gelatinases in bone healing. The focus on mandibular fractures

Directory of Open Access Journals (Sweden)

Kurzepa Jacek

2014-06-01

Full Text Available Due to high amount of collagen fibres in the structure of bone, the enzymes capable of collagen digestion play a key role in bone remodelling. Matrix metalloproteinases (MMPs, prevailing extracellular endopeptideses, can digest extracellularly located proteins, e.g. collagen, proteoglycans, elastin or fibronectin. Among MMPs, collagenases (MMP-1, MMP-8 and MMP-13 and gelatinases (MMP-2 and MMP-9 can cleave collagen particles to forms that are able to undergo further steps of catabolism intracellularly. In addition, activity of the gelatinases (as an activation of proinflammatory cytokines facilitates spreading inflammation that is necessary during the first stage of bone healing. Further studies related to the role of various MMPs in mandibular fractures should precisely explain their function in the bone healing and evaluate the influence of MMPs inhibitors on that process. This review provides the basic information about two groups among MMPs family, collagenases and gelatinases, and their role in repairing processes after mandibular fractures.

Restoration of a Critical Mandibular Bone Defect Using Human Alveolar Bone-Derived Stem Cells and Porous Nano-HA/Collagen/PLA Scaffold

Directory of Open Access Journals (Sweden)

Xing Wang

2016-01-01

Full Text Available Periodontal bone defects occur in a wide variety of clinical situations. Adult stem cell- and biomaterial-based bone tissue regeneration are a promising alternative to natural bone grafts. Recent evidence has demonstrated that two populations of adult bone marrow mesenchymal stromal cells (BMSCs can be distinguished based on their embryonic origins. These BMSCs are not interchangeable, as bones preferentially heal using cells that share the same embryonic origin. However, the feasibility of tissue engineering using human craniofacial BMSCs was unclear. The goal of this study was to explore human craniofacial BMSC-based therapy for the treatment of localized mandibular defects using a standardized, minimally invasive procedure. The BMSCs’ identity was confirmed. Scanning electron microscopy, a cell proliferation assay, and supernatant detection indicated that the nHAC/PLA provided a suitable environment for aBMSCs. Real-time PCR and electrochemiluminescence immunoassays demonstrated that osteogenic markers were upregulated by osteogenic preinduction. Moreover, in a rabbit critical-size mandibular bone defect model, total bone formation in the nHAC/PLA + aBMSCs group was significantly higher than in the nHAC/PLA group but significantly lower than in the nHAC/PLA + preinduced aBMSCs. These findings demonstrate that this engineered bone is a valid alternative for the correction of mandibular bone defects.

Restoration of a Critical Mandibular Bone Defect Using Human Alveolar Bone-Derived Stem Cells and Porous Nano-HA/Collagen/PLA Scaffold

Science.gov (United States)

Wang, Xing; Xing, Helin; Zhang, Guilan; Wu, Xia; Zou, Xuan; Feng, Lin; Wang, Dongsheng; Li, Meng; Zhao, Jing; Du, Jianwei; Lv, Yan; E, Lingling; Liu, Hongchen

2016-01-01

Periodontal bone defects occur in a wide variety of clinical situations. Adult stem cell- and biomaterial-based bone tissue regeneration are a promising alternative to natural bone grafts. Recent evidence has demonstrated that two populations of adult bone marrow mesenchymal stromal cells (BMSCs) can be distinguished based on their embryonic origins. These BMSCs are not interchangeable, as bones preferentially heal using cells that share the same embryonic origin. However, the feasibility of tissue engineering using human craniofacial BMSCs was unclear. The goal of this study was to explore human craniofacial BMSC-based therapy for the treatment of localized mandibular defects using a standardized, minimally invasive procedure. The BMSCs' identity was confirmed. Scanning electron microscopy, a cell proliferation assay, and supernatant detection indicated that the nHAC/PLA provided a suitable environment for aBMSCs. Real-time PCR and electrochemiluminescence immunoassays demonstrated that osteogenic markers were upregulated by osteogenic preinduction. Moreover, in a rabbit critical-size mandibular bone defect model, total bone formation in the nHAC/PLA + aBMSCs group was significantly higher than in the nHAC/PLA group but significantly lower than in the nHAC/PLA + preinduced aBMSCs. These findings demonstrate that this engineered bone is a valid alternative for the correction of mandibular bone defects. PMID:27118977

Assessment of simulated mandibular condyle bone lesions by cone beam computed tomography

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Marques, Alexandre Perez; Perrella, Andreia; Arita, Emiko Saito; Pereira, Marlene Fenyo Soeiro de Matos; Cavalcanti, Marcelo de Gusmao Paraiso, E-mail: alexperez34@gmail.co [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Odontologia. Dept. de Estomatologia

2010-10-15

There are many limitations to image acquisition, using conventional radiography, of the temporomandibular joint (TMJ) region. The Computed Tomography (CT) scan is a better option, due to its higher accuracy, for purposes of diagnosis, surgical planning and treatment of bone injuries. The aim of the present study was to analyze two protocols of cone beam computed tomography for the evaluation of simulated mandibular condyle bone lesions. Spherical lesions were simulated in 30 dry mandibular condyles, using dentist drills and drill bits sizes 1, 3 and 6. Each of the mandibular condyles was submitted to cone beam computed tomography (CBCT) using two protocols: axial, coronal and sagittal multiplanar reconstruction (MPR); and sagittal plus coronal slices throughout the longitudinal axis of the mandibular condyles. For these protocols, 2 observers analyzed the CBCT images independently, regarding the presence or not of injuries. Only one of the observers, however, performed on 2 different occasions. The results were compared to the gold standard, evaluating the percentage of agreement, degree of accuracy of CBCT protocols and observers' examination. The z test was used for the statistical analysis. The results showed there were no statistically significant differences between the 2 protocols. There was greater difficulty in the assessment of small-size simulated lesions (drill no.1). From the results of this study, it can be concluded that CBCT is an accurate tool for analyzing mandibular condyle bone lesions, with the MPR protocol showing slightly better results than the sagittal plus coronal slices throughout the longitudinal axis. (author)

Fractal analysis of mandibular trabecular bone: optimal tile sizes for the tile counting method.

Science.gov (United States)

Huh, Kyung-Hoe; Baik, Jee-Seon; Yi, Won-Jin; Heo, Min-Suk; Lee, Sam-Sun; Choi, Soon-Chul; Lee, Sun-Bok; Lee, Seung-Pyo

2011-06-01

This study was performed to determine the optimal tile size for the fractal dimension of the mandibular trabecular bone using a tile counting method. Digital intraoral radiographic images were obtained at the mandibular angle, molar, premolar, and incisor regions of 29 human dry mandibles. After preprocessing, the parameters representing morphometric characteristics of the trabecular bone were calculated. The fractal dimensions of the processed images were analyzed in various tile sizes by the tile counting method. The optimal range of tile size was 0.132 mm to 0.396 mm for the fractal dimension using the tile counting method. The sizes were closely related to the morphometric parameters. The fractal dimension of mandibular trabecular bone, as calculated with the tile counting method, can be best characterized with a range of tile sizes from 0.132 to 0.396 mm.

Remodeling of the Mandibular Bone Induced by Overdentures Supported by Different Numbers of Implants.

Science.gov (United States)

Li, Kai; Xin, Haitao; Zhao, Yanfang; Zhang, Zhiyuan; Wu, Yulu

2016-05-01

The objective of this study was to investigate the process of mandibular bone remodeling induced by implant-supported overdentures. computed tomography (CT) images were collected from edentulous patients to reconstruct the geometry of the mandibular bone and overdentures supported by implants. Based on the theory of strain energy density (SED), bone remodeling models were established using the user material subroutine (UMAT) in abaqus. The stress distribution in the mandible and bone density change was investigated to determine the effect of implant number on the remodeling of the mandibular bone. The results indicated that the areas where high Mises stress values were observed were mainly situated around the implants. The stress was concentrated in the distal neck region of the distal-most implants. With an increased number of implants, the biting force applied on the dentures was almost all taken up by implants. The stress and bone density in peri-implant bone increased. When the stress reached the threshold of remodeling, the bone density began to decrease. In the posterior mandible area, the stress was well distributed but increased with decreased implant numbers. Changes in bone density were not observed in this area. The computational results were consistent with the clinical data. The results demonstrate that the risk of bone resorption around the distal-most implants increases with increased numbers of implants and that the occlusal force applied to overdentures should be adjusted to be distributed more in the distal areas of the mandible.

Effect of occlusal (mechanical) stimulus on bone remodelling in rat mandibular condyle.

Science.gov (United States)

Gazit, D; Ehrlich, J; Kohen, Y; Bab, I

1987-09-01

Mechanical load influences the remodelling of skeletal tissues. In the mandibular condyle, occlusal alterations and the consequent mechanical stimulus induce changes in chondrocytes and cartilage mineralization. In the present study we quantified in the mandibular condyle the effect of occlusal interference on remodelling of the subchondral bone. Computerized histomorphometry after 5-21-day exposure to the influence of a unilateral occlusal splint revealed an increased rate of trabecular remodelling, consisting of enhancement in osteoblast and osteoclast numbers and activities. The bone formation parameters reached their high values on Days 5 or 9 and remained stable thereafter. Bone resorption showed a gradual increase throughout the experimental period. These results further characterize the temporomandibular joint reaction to occlusal alterations. It is suggested that the present increase in bone turnover together with the known enhancement in chondrogenesis are part of a process of functional adaptation in response to mechanical stimulus.

Mandibular reconstruction using bone allografts

International Nuclear Information System (INIS)

Chang Joon Yim

1999-01-01

. Combinations of allografts and autografts for mandibular reconstruction have enjoyed great success since their introduction in the late 1960's and early 1970's. Due to its high osteogenic potential, marrow and cancellous bone was used for reconstruction of the mandible. For reconstruction of large defects, surgeons used a scaffold to support the cancellous bone. This practice led to the use of allogeneic bone crib in which the cancellous bone could be packed. Reconstruction of the mandible by this combination is now very commonplace

Bone healing around nanocrystalline hydroxyapatite, deproteinized bovine bone mineral, biphasic calcium phosphate, and autogenous bone in mandibular bone defects

DEFF Research Database (Denmark)

Broggini, Nina; Bosshardt, Dieter D; Jensen, Simon S

2015-01-01

The individual healing profile of a given bone substitute with respect to osteogenic potential and substitution rate must be considered when selecting adjunctive grafting materials for bone regeneration procedures. In this study, standardized mandibular defects in minipigs were filled...... with nanocrystalline hydroxyapatite (HA-SiO), deproteinized bovine bone mineral (DBBM), biphasic calcium phosphate (BCP) with a 60/40% HA/β-TCP (BCP 60/40) ratio, or particulate autogenous bone (A) for histological and histomorphometric analysis. At 2 weeks, percent filler amongst the test groups (DBBM (35.65%), HA......-SiO (34.47%), followed by BCP 60/40 (23.64%)) was significantly higher than the more rapidly substituted autogenous bone (17.1%). Autogenous bone yielded significantly more new bone (21.81%) over all test groups (4.91%-7.74%) and significantly more osteoid (5.53%) than BCP 60/40 (3%) and DBBM (2...

The effects of irradiation on the mandibular bone of rats on the low calcium diet

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Hwang, Eui Whan; Lee, Sang Rae [Dept. of Oral Radiology, College of Dentistry, Kyung Hee University, Seoul (Korea, Republic of)

1992-08-15

The purpose of this study was to investigate the changes of morphology and structure of bone tissue in the irradiated mandibular bone in rats which were fed a low calcium diet. In order to carry out this experiment, 64 seven-week old Sprague- Dawley strain rats weighing about 150gms were selected and equally divided into one experimental group of 32 rats and one control group with the remainder. The experimental group and the group were then subdivided into two groups when the rats reached ten-week old, 16 were assigned rats for each subdivided group, exposed to irradiation. The two irradiation groups received a single dose of 20Gy in the jaws area only and irradiated with a cobalt-60 teletherapy unit. The rats in the control and experimental groups were serially termination, both sides of the dead rats mandibular bodies were removed and fixed with 10% neutral formalin. One side of the mandibular body was radiographed with a soft X-ray apparatus. Thereafter, the obtained microradiographs were observed by a light microscope. The remaining side of the mandibular bone was further decalcified and embedded in paraffin as using the general method. The specimen ectioned and stained with hematoxylin and eosin, and Rabit Anti-Human Tumor Necrosis Factor-{alpha}, observed by a light microscope. The obtained results were as follows: 1. Microradiogram revealed that thinning of the cortex and a decrease in the trabecula of the interradicular bone and mandibular body were observed and noted from the start to finish throughout the experiment in the non-irradiated rats on the low calcium diet rather than in the non-irradiated rats on the normal diet.In microscopic observation, there were marked osteolytic changes in the center of the bone marrow. 2. Microradiogram revealed that thinning of the cortex and a decrease in the trabecula of interradicular bone and mandibular body were more marked after 7 days in the irradiated rats in the low calcium diet rather than in the non

Local administration of calcitriol positively influences bone remodeling and maturation during restoration of mandibular bone defects in rats

International Nuclear Information System (INIS)

Liu, Hongrui; Cui, Jian; Feng, Wei; Lv, Shengyu; Du, Juan; Sun, Jing; Han, Xiuchun; Wang, Zhenming; Lu, Xiong; Yimin; Oda, Kimimitsu; Amizuka, Norio; Li, Minqi

2015-01-01

The aim of this study was to investigate the influence of calcitriol on osteoinduction following local administration into mandibular bone defects. Calcitriol-loaded absorbable collagen membrane scaffolds were prepared using the polydopamine coating method and characterized by scanning electron microscopy. Composite scaffolds were implanted into rat mandibular bone defects in the following groups: no graft material (control), bare collagen membrane (CM group), collagen membrane bearing polydopamine coating (DOP/CM group), and collagen membrane bearing polydopamine coating absorbed with calcitriol (CAL/DOP/CM group). At 1, 2, 4 and 8 weeks post-surgery, the osteogenic potential of calcitriol was examined by histological and immunohistochemical methods. Following in vivo implantation, calcitriol-loaded composite scaffolds underwent rapid degradation with pronounced replacement by new bone and induced reunion of the bone marrow cavity. Calcitriol showed strong potential in inhibiting osteoclastogenesis and promotion of osteogenic differentiation at weeks 1, and 2. Furthermore, statistical analysis revealed that the newly formed bone volume in the CAL/DOP/CM group was significantly higher than other groups at weeks 1, and 2. At weeks 4, and 8, the CAL/DOP/CM group showed more mineralized bone and uniform collagen structure. These data suggest that local administration of calcitriol is promising in promoting osteogenesis and mineralization for restoration of mandibular bone defects. - Highlights: • More information on collagen material was added in the revised manuscript. • Masson–Goldner trichrome stain was performed for histomorphometry. • More specific information on calcitriol was supplemented in the Discussion section. • The MOD of ALP and Runx2 was explained in more detail. • The inhibition of osteoclastogenesis was described more accurately in the second paragraph of the discussion

Local administration of calcitriol positively influences bone remodeling and maturation during restoration of mandibular bone defects in rats

Energy Technology Data Exchange (ETDEWEB)

Liu, Hongrui; Cui, Jian; Feng, Wei; Lv, Shengyu; Du, Juan; Sun, Jing; Han, Xiuchun [Department of Bone Metabolism, School of Stomatology Shandong University, Shandong Provincial Key Laboratory of Oral Biomedicine, Jinan (China); Wang, Zhenming; Lu, Xiong [Key Lab of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan (China); Yimin [Department of Advanced Medicine, Graduate School of Medicine, Hokkaido University, Sapporo (Japan); Oda, Kimimitsu [Division of Biochemistry, Niigata University Graduate School of Medical and Dental Sciences, Niigata (Japan); Amizuka, Norio [Department of Developmental Biology of Hard Tissue, Graduate School of Dental Medicine, Hokkaido University, Sapporo (Japan); Li, Minqi, E-mail: liminqi@sdu.edu.cn [Department of Bone Metabolism, School of Stomatology Shandong University, Shandong Provincial Key Laboratory of Oral Biomedicine, Jinan (China)

2015-04-01

The aim of this study was to investigate the influence of calcitriol on osteoinduction following local administration into mandibular bone defects. Calcitriol-loaded absorbable collagen membrane scaffolds were prepared using the polydopamine coating method and characterized by scanning electron microscopy. Composite scaffolds were implanted into rat mandibular bone defects in the following groups: no graft material (control), bare collagen membrane (CM group), collagen membrane bearing polydopamine coating (DOP/CM group), and collagen membrane bearing polydopamine coating absorbed with calcitriol (CAL/DOP/CM group). At 1, 2, 4 and 8 weeks post-surgery, the osteogenic potential of calcitriol was examined by histological and immunohistochemical methods. Following in vivo implantation, calcitriol-loaded composite scaffolds underwent rapid degradation with pronounced replacement by new bone and induced reunion of the bone marrow cavity. Calcitriol showed strong potential in inhibiting osteoclastogenesis and promotion of osteogenic differentiation at weeks 1, and 2. Furthermore, statistical analysis revealed that the newly formed bone volume in the CAL/DOP/CM group was significantly higher than other groups at weeks 1, and 2. At weeks 4, and 8, the CAL/DOP/CM group showed more mineralized bone and uniform collagen structure. These data suggest that local administration of calcitriol is promising in promoting osteogenesis and mineralization for restoration of mandibular bone defects. - Highlights: • More information on collagen material was added in the revised manuscript. • Masson–Goldner trichrome stain was performed for histomorphometry. • More specific information on calcitriol was supplemented in the Discussion section. • The MOD of ALP and Runx2 was explained in more detail. • The inhibition of osteoclastogenesis was described more accurately in the second paragraph of the discussion.

Aneurysmal bone cyst of the mandibular condyle with condylar neck fracture

Energy Technology Data Exchange (ETDEWEB)

Park, Jeong Hoon [Department of Biomedical Engineering, College of Medicine and Healthcare Industry Research Institute, Kyung Hee University, Seoul (Korea, Republic of); Yu, Jae Jung; Kang, Ju Han; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan [Department of Oral and Maxillofacial Radiology, School of Dentistry and Institute of Oral Biology, Kyung Hee University, Seoul (Korea, Republic of)

2009-12-15

Aneurysmal bone cyst (ABC) is relatively rare, non-neoplastic expansible lesion of bone. The case of a 15-year-old male with a ABC of the left mandibular condyle is presented. Panoramic radiograph showed a unilocular radiolucency with thinned coritces and a subcondylar fracture which was due to the trauma. Computed tomography (CT) revealed expansible lesion which had similar attenuation soft tissue. The patient was treated surgically including iliac crestal bone graft.

Aneurysmal bone cyst of the mandibular condyle with condylar neck fracture

International Nuclear Information System (INIS)

Park, Jeong Hoon; Yu, Jae Jung; Kang, Ju Han; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan

2009-01-01

Aneurysmal bone cyst (ABC) is relatively rare, non-neoplastic expansible lesion of bone. The case of a 15-year-old male with a ABC of the left mandibular condyle is presented. Panoramic radiograph showed a unilocular radiolucency with thinned coritces and a subcondylar fracture which was due to the trauma. Computed tomography (CT) revealed expansible lesion which had similar attenuation soft tissue. The patient was treated surgically including iliac crestal bone graft.

Surgical treatments of the impacted canine tooth in young dogs

International Nuclear Information System (INIS)

Amimoto, A.; Iwamoto, S.; Hachimura, H.; Sasaki, K.; Taura, Y.; Nakama, S.; Yamanouchi, T.

1993-01-01

Surgical treatments of the impacted canine tooth were carried out in 8 young dogs, and the results were successful in 12 out of 14 cases (85.7%). The treatments consisting of surgical correction by immediate tipping movement, fenestration of the gingiva, and removal of the impacted tooth, were applied to 14 cases radiographically showing the immature tooth root and no abnormalities in the tooth root or alveolar bone. Impacted teeth were seen in 8 regions of the maxilla and 6 regions of the mandible. Mesioversion was seen in almost all maxillary impacted teeth, while linguoversion or lingual mesioversion in all mandibular cases. Surgical correction was carried out by immediate tipping movement after removal of the retained deciduous canine with or without resection of the alveolar bone. Fixation of the moved teeth was done using a wedge made from the deciduous canine root, which was driven into the vacant alveolar cavity after moving. An additional fixation using a steel wire and/or self-curing resin was done, if necessary

Strategic camouflage treatment of skeletal Class III malocclusion (mandibular prognathism) using bone-borne rapid maxillary expansion and mandibular anterior subapical osteotomy.

Science.gov (United States)

Seo, Yu-Jin; Lin, Lu; Kim, Seong-Hun; Chung, Kyu-Rhim; Nelson, Gerald

2016-01-01

This case report presents the camouflage treatment that successfully improved the facial profile of a patient with a skeletal Class III malocclusion using bone-borne rapid maxillary expansion and mandibular anterior subapical osteotomy. The patient was an 18-year-old woman with chief complaints of crooked teeth and a protruded jaw. Camouflage treatment was chosen because she rejected orthognathic surgery under general anesthesia. A hybrid type of bone-borne rapid maxillary expander with palatal mini-implants was used to correct the transverse discrepancy, and a mandibular anterior subapical osteotomy was conducted to achieve proper overjet with normal incisal inclination and to improve her lip and chin profile. As a result, a Class I occlusion with a favorable inclination of the anterior teeth and a good esthetic profile was achieved with no adverse effects. Therefore, the hybrid type of bone-borne rapid maxillary expander and a mandibular anterior subapical osteotomy can be considered effective camouflage treatment of a skeletal Class III malocclusion, providing improved inclination of the dentition and lip profile. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Antibody-Mediated Osseous Regeneration for Bone Tissue Engineering in Canine Segmental Defects

Directory of Open Access Journals (Sweden)

A. Khojasteh

2018-01-01

Full Text Available Among many applications of therapeutic monoclonal antibodies (mAbs, a unique approach for regenerative medicine has entailed antibody-mediated osseous regeneration (AMOR. In an effort to identify a clinically relevant model of craniofacial defect, the present study investigated the efficacy of mAb specific for bone morphogenetic protein- (BMP- 2 to repair canine segmental mandibular continuity defect model. Accordingly, a 15 mm unilateral segmental defect was created in mandible and fixated with a titanium plate. Anorganic bovine bone mineral with 10% collagen (ABBM-C was functionalized with 25 μg/mL of either chimeric anti-BMP-2 mAb or isotype-matched mAb (negative control. Recombinant human (rh BMP-2 served as positive control. Morphometric analyses were performed on computed tomography (CT and histologic images. Bone densities within healed defect sites at 12 weeks after surgery were 1360.81 ± 10.52 Hounsfield Unit (HU, 1044.27 ± 141.16 HU, and 839.45 ± 179.41 HU, in sites with implanted anti-BMP-2 mAb, rhBMP-2, and isotype mAb groups, respectively. Osteoid bone formation in anti-BMP-2 mAb (42.99% ± 8.67 and rhBMP-2 (48.97% ± 2.96 groups was not significantly different but was higher (p<0.05 than in sites with isotype control mAb (26.8% ± 5.35. In view of the long-term objective of translational application of AMOR in humans, the results of the present study demonstrated the feasibility of AMOR in a large clinically relevant animal model.

Bone structure of the temporo-mandibular joint in the individuals aged 18-25.

Science.gov (United States)

Parafiniuk, M; Gutsch-Trepka, A; Trepka, S; Sycz, K; Wolski, S; Parafiniuk, W

1998-01-01

Osteohistometric studies were performed in 15 female and 15 male cadavers aged 18-25. Condyloid process and right and left acetabulum of the temporo-mandibular joint have been studied. Density has been investigated using monitor screen linked with microscope (magnification 80x). Density in the spongy part of the condyloid process was 26.67-26.77%; in the subchondrial layer--72.13-72.72%, and in the acetabular wall 75.03-75.91%. Microscopic structure of the bones of the temporo-mandibular joint revealed no differences when compared with images of compact and cancellous bone shown in the histology textbooks. Sex and the side of the body had no influence on microscopic image and proportional bone density. Isles of chondrocytes in the trabeculae of the spongy structure of the condyloid process were found in 4 cases and isles of the condensed bone resembling the compact pattern in 7 cases.

Bone augmentation of the osteo-odonto alveolar lamina in MOOKP--will it delay laminar resorption?

Science.gov (United States)

Iyer, Geetha; Srinivasan, Bhaskar; Agarwal, Shweta; Rishi, Ekta; Rishi, Pukhraj; Rajan, Gunaseelan; Shanmugasundaram, Shanmugasundaram

2015-07-01

We aimed to describe a new technique and analyse the early outcomes of augmenting the canine tooth using a mandibular bone graft in an attempt to delay or retard the process of laminar resorption following the modified osteo odonto keratoprosthesis (MOOKP) procedure. This was a retrospective case series. Eyes that underwent the bone augmentation procedure between December 2012 and February 2014 were retrospectively analysed. The procedure, performed by the oromaxillofacial surgeon, involved securing a mandibular bone graft beneath the periosteum on the labial aspect of the canine tooth chosen to be harvested for the MOOKP procedure. This procedure was performed simultaneously with the Stage 1 A of the MOOKP. Three months later, the tooth was harvested and fashioned into the osteo-odonto alveolar lamina similar to the method described in the Rome-Vienna Protocol. The bone augmentation procedure was performed in 11 eyes (five SJS/ six chemical injuries). The mean follow-up after Stage 2 of MOOKP procedure in these eyes was 7.45 months (2 to 20 months). Complications noted were peripheral laminar exposure (three eyes-SJS) and bone graft exposure and necrosis in the mouth (nine-SJS). No evidence of clinical laminar resorption was noted in any of the eyes. Laminar resorption in MOOKP can lead to vision and globe threatening complications due to the consequent cylinder instability and chances of extrusion. Augmenting the bone on the labial aspect of the canine tooth might have a role to play in delaying or preventing laminar resorption.

The correlationship between mandibular radiomorphometric indices in panorama and bone mineral density in Cu-equivalent image of intraoral film

International Nuclear Information System (INIS)

Kim, Jae Duk

2003-01-01

To determine whether the mandibular radiomorphometric indices in panoramic radiography are correlated with the bone mineral density of Cu-equivalent images in intraoral film. The bone mineral density (BMD) of the mandibular premolar area was measured in the Cu-equivalent image of intraoral film. The Panoramic Mandibular Index (PMI) and Mandibular Cortical Width (MCW) were measured in panoramic radiographs of six dry mandibles, and the Pearson correlation between PMI, MCW, and BMD were tested. There were no significant correlations between PMI and BMD (r=0.280), nor between MCW and BMD (r=0.237). The results show that PMI and MCW were poor diagnostic indicators of mandibular BMD in the six dry mandibles used in this study. The correlationship between the mandibular radiomorphometric indices (PMI and MCW) and mandibular BMD needs to be researched further using large in vivo patient samples.

Orthopantomographic study of the alveolar bone level on periodontal disease

International Nuclear Information System (INIS)

Lee, Ki Sik; You, Dong Soo

1972-01-01

The author had measured the alveolar bone level of periodontal disease on 50 cases of orthopantomogram to detect the degree of alveolar bone resorption of both sexes of Korean. The results were obtained as follows; 1. Alveolar bone resorption of mesial and distal portion was similar in same patient. 2. The order of alveolar bone resorption was mandibular anterior region, posterior region, canine and premolar region of both jaws. 3. The degree of alveolar bone destruction was severe in shorter root length than longer one. 4. The degree of alveolar bone resorption was severe in fourth decades.

Orthopantomographic study of the alveolar bone level on periodontal disease

Energy Technology Data Exchange (ETDEWEB)

Lee, Ki Sik; You, Dong Soo [College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

1972-11-15

The author had measured the alveolar bone level of periodontal disease on 50 cases of orthopantomogram to detect the degree of alveolar bone resorption of both sexes of Korean. The results were obtained as follows; 1. Alveolar bone resorption of mesial and distal portion was similar in same patient. 2. The order of alveolar bone resorption was mandibular anterior region, posterior region, canine and premolar region of both jaws. 3. The degree of alveolar bone destruction was severe in shorter root length than longer one. 4. The degree of alveolar bone resorption was severe in fourth decades.

MRI of the temporo-mandibular joint: which sequence is best suited to assess the cortical bone of the mandibular condyle? A cadaveric study using micro-CT as the standard of reference

International Nuclear Information System (INIS)

Karlo, Christoph A.; Patcas, Raphael; Signorelli, Luca; Mueller, Lukas; Kau, Thomas; Watzal, Helmut; Kellenberger, Christian J.; Ullrich, Oliver; Luder, Hans-Ulrich

2012-01-01

To determine the best suited sagittal MRI sequence out of a standard temporo-mandibular joint (TMJ) imaging protocol for the assessment of the cortical bone of the mandibular condyles of cadaveric specimens using micro-CT as the standard of reference. Sixteen TMJs in 8 human cadaveric heads (mean age, 81 years) were examined by MRI. Upon all sagittal sequences, two observers measured the cortical bone thickness (CBT) of the anterior, superior and posterior portions of the mandibular condyles (i.e. objective analysis), and assessed for the presence of cortical bone thinning, erosions or surface irregularities as well as subcortical bone cysts and anterior osteophytes (i.e. subjective analysis). Micro-CT of the condyles was performed to serve as the standard of reference for statistical analysis. Inter-observer agreements for objective (r = 0.83-0.99, P < 0.01) and subjective (κ = 0.67-0.88) analyses were very good. Mean CBT measurements were most accurate, and cortical bone thinning, erosions, surface irregularities and subcortical bone cysts were best depicted on the 3D fast spoiled gradient echo recalled sequence (3D FSPGR). The most reliable MRI sequence to assess the cortical bone of the mandibular condyles on sagittal imaging planes is the 3D FSPGR sequence. (orig.)

MRI of the temporo-mandibular joint: which sequence is best suited to assess the cortical bone of the mandibular condyle? A cadaveric study using micro-CT as the standard of reference

Energy Technology Data Exchange (ETDEWEB)

Karlo, Christoph A. [University Hospital Zurich, Department of Diagnostic and Interventional Radiology, Zurich (Switzerland); University Children' s Hospital Zurich, Department of Diagnostic Imaging, Zurich (Switzerland); Patcas, Raphael; Signorelli, Luca; Mueller, Lukas [University of Zurich, Clinic for Orthodontics and Pediatric Dentistry, Center of Dental Medicine, Zurich (Switzerland); Kau, Thomas; Watzal, Helmut; Kellenberger, Christian J. [University Children' s Hospital Zurich, Department of Diagnostic Imaging, Zurich (Switzerland); Ullrich, Oliver [University of Zurich, Institute of Anatomy, Faculty of Medicine, Zurich (Switzerland); Luder, Hans-Ulrich [University of Zurich, Section of Orofacial Structures and Development, Center of Dental Medicine, Zurich (Switzerland)

2012-07-15

To determine the best suited sagittal MRI sequence out of a standard temporo-mandibular joint (TMJ) imaging protocol for the assessment of the cortical bone of the mandibular condyles of cadaveric specimens using micro-CT as the standard of reference. Sixteen TMJs in 8 human cadaveric heads (mean age, 81 years) were examined by MRI. Upon all sagittal sequences, two observers measured the cortical bone thickness (CBT) of the anterior, superior and posterior portions of the mandibular condyles (i.e. objective analysis), and assessed for the presence of cortical bone thinning, erosions or surface irregularities as well as subcortical bone cysts and anterior osteophytes (i.e. subjective analysis). Micro-CT of the condyles was performed to serve as the standard of reference for statistical analysis. Inter-observer agreements for objective (r = 0.83-0.99, P < 0.01) and subjective ({kappa} = 0.67-0.88) analyses were very good. Mean CBT measurements were most accurate, and cortical bone thinning, erosions, surface irregularities and subcortical bone cysts were best depicted on the 3D fast spoiled gradient echo recalled sequence (3D FSPGR). The most reliable MRI sequence to assess the cortical bone of the mandibular condyles on sagittal imaging planes is the 3D FSPGR sequence. (orig.)

Preoperative measurement of canine primary bone tumors, using radiography and bone scintigraphy

International Nuclear Information System (INIS)

Lamb, C.R.; Berg, J.; Bengston, A.E.

1990-01-01

Specimens of 20 canine primary bone tumors (18 osteosarcoma, 2 fibrosarcoma) were examined to compare the maximal axial length of gross tumor with the length of the lesion seen on preoperative radiographs and 99mTc methylene diphosphonate bone scintigraphic images. Radiographs defined the length of the tumor to within +/- 10% of the gross measurement for 6 (30%), underestimated it for 12 (60%), and overestimated it for 2 (10%) specimens. Bone scintigraphy defined tumor length within +/- 10% for 8 (40%), underestimated it for 1 (5%), and overestimated it for the remaining 11 (55%) specimens. Use of radiographic evaluation alone could result in underestimation of the diaphyseal extent of a primary bone tumor, with risk of incomplete resection. Bone scan images tend to overestimate tumor length and, therefore, may provide safer resection guidelines

Predictability of bone density at posterior mandibular implant sites using cone-beam computed tomography intensity values

OpenAIRE

Alkhader, Mustafa; Hudieb, Malik; Khader, Yousef

2017-01-01

Objective: The aim of this study was to investigate the predictability of bone density at posterior mandibular implant sites using cone-beam computed tomography (CBCT) intensity values. Materials and Methods: CBCT cross-sectional images for 436 posterior mandibular implant sites were selected for the study. Using Invivo software (Anatomage, San Jose, California, USA), two observers classified the bone density into three categories: low, intermediate, and high, and CBCT intensity values were g...

Effect of mandibular plane angle on image dimensions in linear tomography

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Bashizadeh Fakhar H

2011-02-01

Full Text Available "nBackground and Aims: Accurate bone measurements are essential for determining the optimal size and length of proposed implants. The radiologist should be aware of the head position effects on image dimensions in each imaging technique. The purpose of this study was to evaluate the effect of mandibular plane angle on image dimensions in linear tomography."nMaterials and Methods: In this in vitro study, the vertical dimensions of linear tomograms taken from 3 dry mandibles in different posteroantenior or mediolateral tilts were compared with actual condition. In order to evaluate the effects of head position in linear tomography, 16 series of images while mandibular plane angle was tilted with 5, 10, 15 and 20 degrees in anterior, posterior, medial, or lateral angulations as well as a series of standard images without any tilt in mandibular position were taken. Vertical distances between the alveolar crest and the superior border of the inferior alveolar canal were measured in posterior mandible and the vertical distances between the alveolar crest and inferior rim were measured in anterior mandible in 12 sites of tomograms. Each bone was then sectioned through the places marked with a radiopaque object. The radiographic values were compared with the real conditions. Repeat measure ANOVA was used to analyze the data."nResults: The findings of this study showed that there was significant statistical difference between standard position and 15º posteroanterior tilt (P<0.001. Also there was significant statistical difference between standard position and 10º lateral tilt (P<0.008, 15º tilt (P<0.001, and 20º upward tilt (P<0.001. In standard mandibular position with no tilt, the mean exact error was the same in all regions (0.22±0.19 mm except the premolar region which the mean exact error was calculated as 0.44±0.19 mm. The most mean exact error among various postroanterior tilts was seen in 20º lower tilt in the canine region (1±0.88 mm

A new method of prefabricated vascularized allogenic bone grafts for maxillo-mandibular reconstruction

International Nuclear Information System (INIS)

Pill-Hoon Choung

1999-01-01

Although there are various applications of allogenic bone grafts, a new technique of prevascularized lyophilized allogenic bone grafting for maxillo-mandibular reconstruction will be presented. Allogenic bone has been made by author's protocol for jaw defects as a powder, chip or block bone type. The author used lyophilized allogenic bone grafts for discontinuity defects as a block bone. In those cases, neovascularization and resorption of the allogenic bone were important factors for success of grafting. To overcome the problems, the author designed the technique of prefabricated vascularization of allogenic bone, which was lyophilized cranium, with an application of bovine BMP or not. Lyophilized cranial bone was designed for the defects and was put into the scalp. After confirming a hot spot via scintigram several months later, vascularized allogenic bone was harvested pedicled on the parietotemporal fascia based on the superficial temporal artery and vein. Vascularized allogenic cranial bone was rotated into the defect and fixed rigidly. Postoperatively, there was no severe resorption and functional disturbance of the mandible. In this technique, BMP seems to be an important role to help osteogenesis and neovascularization. Eight patients underwent prefabricated vascularization of allogenic bone grafts. Among them, four cases of reconstruction in mandibular discontinuity defects and one case of reconstruction in maxillectomy defect underwent this method, which will be presented with good results. This method may be an alternative technique of microvascular free bone graft

Mandibular bone necrosis after use of paraformaldehyde-containing paste

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Chi-hwan Lee

2016-11-01

Full Text Available Paraformaldehyde has been used in the past as a pulpotomy agent. However, it has a severe cytotoxic effect and may cause alveolar bone necrosis. Depulpin, a devitalizing agent containing 49% paraformaldehyde, is no longer used frequently due to its severe side effects. In the two cases described in the present study, Depulpin was used as a devitalizing agent during root canal treatment. It caused a gradual loss of sensibility in adjacent teeth, gingival necrosis, and osteomyelitis. This case report demonstrates the serious side effects of using a paraformaldehyde-containing paste as a devitalizing agent for pulp, particularly mandibular bone necrosis.

Reconstruction of mandibular defects using nonvascularized autogenous bone graft in Nigerians

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Kizito Chioma Ndukwe

2014-01-01

Full Text Available Objectives: The aim of this study is to evaluate the success rate and complications of mandibular reconstruction with nonvascularized bone graft in Ile-Ife, Nigeria. Patients and Methods: A total of 25 patients who underwent reconstruction of mandibular discontinuity defects between January 2003 and February 2012, at the Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife constituted the study sample. Relevant information was retrieved from the patients′ records. This information include patients′ demographics (age and sex as well as the type of mandibular defect, cause of the defect, type of mandibular resection done, source of the bone graft used, and the method of graft immobilization. Morbidity associated with the graft procedures were assessed by retrieving information on graft failures, length of hospital stay following surgery, rehabilitation device used and associated graft donor and recipient site complications. Result: There were 12 males and 13 females with a male:female ratio was 1:1.1. The age of the patients ranged from 13 to 73 years with a mean age for males 32.7 ± standard deviation (SD 12.9 and for females 35.0 ± SD 17.1. Jaw defect was caused by resection for tumours and other jaw pathologies in 92% of cases. Complete symphyseal involvement defect was the most common defect recorded 11 (44%. Reconstruction with nonvascularized rib graft accounted for 68% of cases while iliac crest graft was used in 32% of the patients. Successful take of the grafts was recorded in 22 patients while three cases failed. Wound dehiscence (two patients and postoperative wound infection (eight patients were the most common complications recorded. Conclusion: The use of nonvascularized graft is still relevant in the reconstruction of large mandibular defects caused by surgical ablation of benign conditions in Nigerians. Precise surgical planning and execution, extended antibiotic therapy, and meticulous postoperative care

MRI of the temporo-mandibular joint: which sequence is best suited to assess the cortical bone of the mandibular condyle? A cadaveric study using micro-CT as the standard of reference.

Science.gov (United States)

Karlo, Christoph A; Patcas, Raphael; Kau, Thomas; Watzal, Helmut; Signorelli, Luca; Müller, Lukas; Ullrich, Oliver; Luder, Hans-Ulrich; Kellenberger, Christian J

2012-07-01

To determine the best suited sagittal MRI sequence out of a standard temporo-mandibular joint (TMJ) imaging protocol for the assessment of the cortical bone of the mandibular condyles of cadaveric specimens using micro-CT as the standard of reference. Sixteen TMJs in 8 human cadaveric heads (mean age, 81 years) were examined by MRI. Upon all sagittal sequences, two observers measured the cortical bone thickness (CBT) of the anterior, superior and posterior portions of the mandibular condyles (i.e. objective analysis), and assessed for the presence of cortical bone thinning, erosions or surface irregularities as well as subcortical bone cysts and anterior osteophytes (i.e. subjective analysis). Micro-CT of the condyles was performed to serve as the standard of reference for statistical analysis. Inter-observer agreements for objective (r = 0.83-0.99, P < 0.01) and subjective (κ = 0.67-0.88) analyses were very good. Mean CBT measurements were most accurate, and cortical bone thinning, erosions, surface irregularities and subcortical bone cysts were best depicted on the 3D fast spoiled gradient echo recalled sequence (3D FSPGR). The most reliable MRI sequence to assess the cortical bone of the mandibular condyles on sagittal imaging planes is the 3D FSPGR sequence. MRI may be used to assess the cortical bone of the TMJ. • Depiction of cortical bone is best on 3D FSPGR sequences. • MRI can assess treatment response in patients with TMJ abnormalities.

A patient with mandibular deviation and 3 mandibular incisors treated with asymmetrically bent improved superelastic nickel-titanium alloy wires.

Science.gov (United States)

Ikeda, Yuhei; Kokai, Satoshi; Ono, Takashi

2018-01-01

Skeletal and dental discrepancies cause asymmetric malocclusions in orthodontic patients. It is difficult to achieve adequate functional occlusion and guidance in patients with congenital absence of a mandibular incisor due to the tooth-size discrepancy. Here, we describe the orthodontic treatment of a 22-year-old woman with an asymmetric Angle Class II malocclusion, mandibular deviation to the left, and 3 mandibular incisors. The anterior teeth and maxillary canines were crowded. We used an improved superelastic nickel-titanium alloy wire (Tomy International, Tokyo, Japan) to compensate for the asymmetric mandibular arch and an asymmetrically bent archwire to move the maxillary molars distally. A skeletal anchorage system provided traction for intermaxillary elastics, and extractions were not needed. We alleviated the crowding and created an ideal occlusion with proper overjet, overbite, and anterior guidance with Class I canine and molar relationships. This method of treatment with an asymmetrically bent nickel-titanium alloy wire provided proper Class I occlusion and anterior guidance despite the mandibular deviation to the left and 3 mandibular incisors, without the need for extractions. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Mechanical properties of cancellous bone in the human mandibular condyle are anisotropic

DEFF Research Database (Denmark)

Giesen, EB; Ding, Ming; Dalstra, M

2001-01-01

The objective of the present study was (1) to test the hypothesis that the elastic and failure properties of the cancellous bone of the mandibular condyle depend on the loading direction, and (2) to relate these properties to bone density parameters. Uniaxial compression tests were performed......). Archimedes' principle was applied to determine bone density parameters. The cancellous bone was in axial loading 3.4 times stiffer and 2.8 times stronger upon failure than in transverse loading. High coefficients of correlation were found among the various mechanical properties and between them...

The variation of cancellous bones at lumbar vertebra, femoral neck, mandibular angle and rib in ovariectomized sheep.

Science.gov (United States)

Zhang, Yongqiang; Li, Yongfeng; Gao, Qi; Shao, Bo; Xiao, Jianrui; Zhou, Hong; Niu, Qiang; Shen, Mingming; Liu, Baolin; Hu, Kaijin; Kong, Liang

2014-07-01

This study aimed to compare the variation of cancellous bones at four skeletal sites: lumbar vertebra, femoral neck, mandibular angle and rib in ovariectomized sheep. Sixteen adult sheep were randomly divided into two groups: eight sheep were ovariectomized served as experimental group; the other eight untreated sheep were served as control group. Bone mineral density was assessed by dual-energy X-ray absorptiometry on lumbar vertebrae at baseline and twelve months after ovariectomy. After 12 months, lumbar vertebrae L3 and L4, femoral necks, mandibular angles and the fourth ribs were harvested for micro-CT scanning, histological analysis and biomechanical test. The results showed that bone mineral density of lumbar vertebra decreased significantly in twelfth month (pbone volume/total volume decreased by 45.6%, 36.1% 21.3% and 18.7% in lumbar vertebrae, femoral necks, mandibular angles and ribs in experimental group (pbones to oestrogen deficiency in ovariectomized sheep was site-specific on a pattern as follows: lumbar vertebra, femoral neck, mandibular angle and rib. Copyright © 2014 Elsevier Ltd. All rights reserved.

Differential response of risedronate on tibial and mandibular bone quality in glucocorticoid-treated growing rats

International Nuclear Information System (INIS)

Fujita, Yuko

2008-01-01

Glucocorticoids induce bone loss and retard bone growth in children. In this study we investigated the effect of treatment with risedronate on glucocorticoid -prednisolone-induced decreases in bone density, quality, strength and growth of the tibia and mandible in growing rats. Trabecular and cortical bone structure was measured by peripheral quantitative computed tomography (pQCT) and three-dimensional (3D) micro-computed tomography (micro-CT). Indicators of bone strength were calculated from cortical bone density and the modulus of sections obtained from pQCT analysis. Tibial and mandibular bone sizes were also measured. Prednisolone decreased the bone growth of both tibia and mandible. It also caused deterioration of trabecular and cortical bone structure and strength in the mandible, and in cortical bone in the tibia, but had no effect on trabecular bone in the tibia. Risedronate inhibited the prednisolone-induced decreases in tibial width and mandibular length and height but did not improve the retardation of longitudinal bone growth. Risedronate prevented prednisolone-induced deterioration of trabecular and cortical bone architecture. In the mandible, this protective effect of risedronate was accompanied by an increase in cortical bone density and in bone strength. These findings show that risedronate inhibits prednisolone-induced loss of bone density, structure, decrease in bone strength, and retardation of bone growth in the mandible in young growing rats. (author)

Bone compaction enhances implant fixation in a canine gap model

DEFF Research Database (Denmark)

Kold, Søren; Rahbek, Ole; Toft, Marianne

2005-01-01

A new bone preparation technique, compaction, has increased fixation of implants inserted with exact-fit or press-fit to bone. Furthermore, a demonstrated spring-back effect of compacted bone might be of potential value in reducing the initial gaps that often exist between clinical inserted...... implants and bone. However, it is unknown whether the compression and breakage of trabeculae during the compaction procedure results in impaired gap-healing of compacted bone. Therefore, we compared compaction with conventional drilling in a canine gap model. Grit-blasted titanium implants (diameter 6 mm...... that the beneficial effect of reduced gap size, as compacted bone springs back, is not eliminated by an impaired gap-healing of compacted bone....

Distributional variations in trabecular architecture of the mandibular bone: an in vivo micro-CT analysis in rats.

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Zhongshuang Liu

Full Text Available To evaluate the effect of trabecular thickness and trabecular separation on modulating the trabecular architecture of the mandibular bone in ovariectomized rats.Fourteen 12-week-old adult female Wistar rats were divided into an ovariectomy group (OVX and a sham-ovariectomy group (sham. Five months after the surgery, the mandibles from 14 rats (seven OVX and seven sham were analyzed by micro-CT. Images of inter-radicular alveolar bone of the mandibular first molars underwent three-dimensional reconstruction and were analyzed.Compared to the sham group, trabecular thickness in OVX alveolar bone decreased by 27% (P = 0.012, but trabecular separation in OVX alveolar bone increased by 59% (P = 0.005. A thickness and separation map showed that trabeculae of less than 100 μm increased by 46%, whereas trabeculae of more than 200 μm decreased by more than 40% in the OVX group compared to those in the sham group. Furthermore, the OVX separation of those trabecular of more than 200 μm was 65% higher compared to the sham group. Bone mineral density (P = 0.028 and bone volume fraction (p = 0.001 were also significantly decreased in the OVX group compared to the sham group.Ovariectomy-induced bone loss in mandibular bone may be related to the distributional variations in trabecular thickness and separation which profoundly impact the modulation of the trabecular architecture.

Root length and alveolar bone level of impacted canines and adjacent teeth after orthodontic traction: a long-term evaluation

Science.gov (United States)

da SILVA, Aldir Cordeiro; CAPISTRANO, Anderson; de ALMEIDA-PEDRIN, Renata Rodrigues; CARDOSO, Maurício de Almeida; CONTI, Ana Cláudia de Castro Ferreira; CAPELOZZA, Leopoldino

2017-01-01

Abstract Objective The aim of this retrospective study was to evaluate the long-term effects of orthodontic traction on root length and alveolar bone level in impacted canines and adjacent teeth. Material and Methods Sample consisted of 16 patients (nine males and seven females), mean initial age 11 years and 8 months presenting with unilaterally maxillary impacted canines, palatally displaced, treated with the same surgical and orthodontic approach. Teeth from the impacted-canine side were assigned as Group I (GI), and contralateral teeth as control, Group II (GII). The mean age of patients at the end of orthodontic treatment was 14 years and 2 months and the mean post-treatment time was 5 years and 11 months. Both contralateral erupted maxillary canines and adjacent teeth served as control. Root length and alveolar bone level (buccal and palatal) were evaluated on cone-beam computed tomography (CBCT) images. The comparison of root length and alveolar bone level changes between groups were assessed by applying paired t-test, at a significance level of 5% (p<0.05). Results There were no statistically significant differences in root length and buccal and palatal bone levels of canines and adjacent teeth among groups. Conclusions Impacted canine treatment by closed-eruption technique associated with canine crown perforation, has a minimal effect on root length and buccal and palatal alveolar bone level in both canine and adjacent teeth, demonstrating that this treatment protocol has a good long-term prognosis. PMID:28198979

The correlation between mineralization degree and bone tissue stiffness in the porcine mandibular condyle

NARCIS (Netherlands)

Willems, N.M.B.K.; Mulder, L.; Toonder, den J.M.J.; Zentner, A.; Langenbach, G.E.J.

2014-01-01

The aim of this study was to correlate the local tissue mineral density (TMD) with the bone tissue stiffness. It was hypothesized that these variables are positively correlated. Cancellous and cortical bone samples were derived from ten mandibular condyles taken from 5 young and 5 adult female pigs.

Predictability of bone density at posterior mandibular implant sites using cone-beam computed tomography intensity values.

Science.gov (United States)

Alkhader, Mustafa; Hudieb, Malik; Khader, Yousef

2017-01-01

The aim of this study was to investigate the predictability of bone density at posterior mandibular implant sites using cone-beam computed tomography (CBCT) intensity values. CBCT cross-sectional images for 436 posterior mandibular implant sites were selected for the study. Using Invivo software (Anatomage, San Jose, California, USA), two observers classified the bone density into three categories: low, intermediate, and high, and CBCT intensity values were generated. Based on the consensus of the two observers, 15.6% of sites were of low bone density, 47.9% were of intermediate density, and 36.5% were of high density. Receiver-operating characteristic analysis showed that CBCT intensity values had a high predictive power for predicting high density sites (area under the curve [AUC] =0.94, P < 0.005) and intermediate density sites (AUC = 0.81, P < 0.005). The best cut-off value for intensity to predict intermediate density sites was 218 (sensitivity = 0.77 and specificity = 0.76) and the best cut-off value for intensity to predict high density sites was 403 (sensitivity = 0.93 and specificity = 0.77). CBCT intensity values are considered useful for predicting bone density at posterior mandibular implant sites.

New bone formation and trabecular bone microarchitecture of highly porous tantalum compared to titanium implant threads: A pilot canine study.

Science.gov (United States)

Lee, Jin Whan; Wen, Hai Bo; Gubbi, Prabhu; Romanos, Georgios E

2018-02-01

This study evaluated new bone formation activities and trabecular bone microarchitecture within the highly porous region of Trabecular Metal™ Dental Implants (TM) and between the threads of Tapered Screw-Vent® Dental Implants (TSV) in fresh canine extraction sockets. Eight partially edentulated dogs received four implants (4.1 mmD × 13 mmL) bilaterally in mandibular fresh extraction sockets (32 TM, 32 TSV implants), and allowed to heal for 2, 4, 8, and 12 weeks. Calcein was administered to label mineralizing bone at 11 and 4 days before euthanasia for dogs undergoing all four healing periods. Biopsies taken at each time interval were examined histologically. Histomorphometric assay was conducted for 64 unstained and 64 stained slides at the region of interest (ROI) (6 mm long × 0.35 mm deep) in the midsections of the implants. Topographical and chemical analyses were also performed. Histomorphometry revealed significantly more new bone in the TM than in the TSV implants at each healing time (p = .0014, .0084, .0218, and .0251). Calcein-labeled data showed more newly mineralized bone in the TM group than in the TSV group at 2, 8, and 12 weeks (p = .045, .028, .002, respectively) but not at 4 weeks (p = .081). Histologically TM implants exhibited more bone growth and dominant new immature woven bone at an earlier time point than TSV implants. The parameters representing trabecular bone microarchitecture corroborated faster new bone formation in the TM implants when compared to the TSV implants. TM exhibited an irregular faceted topography compared to a relatively uniform microtextured surface for TSV. Chemical analysis showed peaks associated with each implant's composition material, and TSV also showed peaks reflecting the elements of the calcium phosphate blasting media. Results suggest that the healing pathway associated with the highly porous midsection of TM dental implant could enable faster and stronger secondary implant stability than

Changed morphology and mechanical properties of cancellous bone in the mandibular condyles of edentate people

DEFF Research Database (Denmark)

Ding, Ming

2004-01-01

Since edentate subjects have a reduced masticatory function, it can be expected that the morphology of the cancellous bone of their mandibular condyles has changed according to the altered mechanical environment. In the present study, the morphology of cylindrical cancellous bone specimens...

Isolation, culture expansion and characterization of canine bone marrow derived mesenchymal stem cells

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D Kazemi

2016-07-01

Full Text Available The purpose of the present study was to isolate, culture expand and characterize canine bone marrow derived mesenchymal stem cells. Bone marrow aspirates of 15 adult male dogs were collected to this end and their mononuclear cells isolated by centrifugation and cultured in standard media. The adherent cells were isolated and their mesenchymal origin was confirmed at 3rd passage by cellular morphology, expression of surface antigens and differentiation to osteogenic and adipogenic lineage. After 4 days, spindle shaped fibroblast like cells which were apparently bone marrow derived mesenchymal stem cells appeared in culture medium and their numbers increased over time. The cells reached 3rd passage with over 75% confluent after a mean of 22.89±5.75 days. Flow cytometric analysis revealed that the cells negatively expressed CD34 and CD45 antigens while positively expressing CD44 and CD105 antigens. Differentiation into osteogenic and adipogenic lineage had taken place after one month culture in induction medium. VDR, COL1A1, BGLAP and SPARC gene expression indicated that mesenchymal stem cells isolated from canine bone marrow had differentiated into osteogenic lineage. These findings can form the basis of any forthcoming clinical studies involving the use of canine mesenchymal stem cells particularly in the field of bone and cartilage regeneration.

Radiographic images of cysts in the maxillar and mandibular bone structures

International Nuclear Information System (INIS)

Klemova, J.; Jenca, A.; Durovic, E.

2008-01-01

The authors give a description of the radiographs of cysts in maxillar and mandibular bone structures in this article. In the past three years there have been 130 patients treated with the diagnosis of cysts and pseudocysts. They were divided into two categories by their relationship to the teeth. (authors)

Revascularization of calvarial, mandibular, tibial, and iliac bone grafts in rats

DEFF Research Database (Denmark)

Pinholt, E M; Solheim, E; Talsnes, O

1994-01-01

Some studies have suggested that membranous bone grafts undergo less resorption than endochondral grafts, and faster revascularization of the former has been proposed as the explanation. We studied fresh syngeneic full-thickness bone grafts from calvaria, mandibula, tibia diaphysis, and iliac bone...... implanted in the back muscles of young Lewis rats. As a measure of the quantity of cancellous bone in grafts before implantation, the ratio of the total area of soft-tissue spaces to the total area of the graft was measured histomorphometrically. Revascularization in grafts 3 weeks postoperatively...... was evaluated by deposit of 141Ce-labeled microspheres. Both the quantity of cancellous bone (before implantation) and the revascularization (3 weeks postoperatively) were greater in the mandibular and iliac bone grafts than in the calvarial and tibia diaphyseal grafts. The results suggest that the anatomical...

Evaluation of the Root and Canal Morphology of Mandibular Permanent Anterior Teeth in an Iranian Population by Cone-Beam Computed Tomography

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Mohsen Aminsobhani

2013-01-01

Full Text Available Objective: To evaluate differences in the root and canal configurations of mandibular permanent anterior incisors and canines in an Iranian population by means of Cone Beam CT (CBCT images.Materials and Methods: Four hundred CBCT images of mandibular permanent incisors and canines that met the inclusion criteria were evaluated. Vertucci´s classification was used to evaluate the number of roots, number of root canals, root lengths, root curvatures and canal types.Results: Totally 632 central incisors, 614 lateral incisors and 608 canines were evaluated. The average length of the mandibular central, lateral incisors and canines was 21.3±0.10, 21.9± 0.13 and 25.1± 0.11 mm, respectively. All of the mandibular central and lateral incisors had one root, but the incidence of single-rooted mandibular canines and two-rooted mandibular canines was 96.3% and 4.7%, respectively. The majority of mandibular central, lateral incisors and canines had one canal (72.7%, 70.6% and 71.8%, respectively. Five types of Vertucci canal configurations were seen in the evaluated teeth. Type 1 Vertucci configuration was the most prevalent configuration (72.3%, 70.6% and 71.8% for the central, lateral incisors and canines, respectively, and type 5 Vertucci canal configuration was the least prevalent type seen (3.3%, 3.2% and 2.3% for the central, lateral incisors and canines, respectively. The most frequent root curvatures in these teeth were distally and buccally. No significant difference was seen between male and female patients regarding any of the parameters evaluated in this study (p>0.05.Conclusion: More attention should be given to the detection of additional canals and the recognition of canal curvature in Iranian patients.

A magnetic resonance imaging study on changes in rat mandibular bone marrow and pulp tissue after high-dose irradiation

Energy Technology Data Exchange (ETDEWEB)

Lee, Wan; Lee, Byung Do [Dept. of Oral and Maxillofacial Radiology and Wonkwang Dental Research Institute, College of Dentistry, Wonkwang University, Iksan (Korea, Republic of); Lee, Kang Kyoo [Dept. of Radiation Oncology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); Koh, Kwang Joon [Dept. of Oral and Maxillofacial Radiology, School of Dentistry and Institute of Oral Bioscience, Chonbuk National University, Jeonju (Korea, Republic of)

2014-03-15

This study was designed to evaluate whether magnetic resonance imaging (MRI) is appropriate for detecting early changes in the mandibular bone marrow and pulp tissue of rats after high-dose irradiation. The right mandibles of Sprague-Dawley rats were irradiated with 10 Gy (Group 1, n=5) and 20 Gy (Group 2, n=5). Five non-irradiated animals were used as controls. The MR images of rat mandibles were obtained before irradiation and once a week until week 4 after irradiation. From the MR images, the signal intensity (SI) of the mandibular bone marrow and pulp tissue of the incisor was interpreted. The MR images were compared with the histopathologic findings. The SI of the mandibular bone marrow had decreased on T2-weighted MR images. There was little difference between Groups 1 and 2. The SI of the irradiated groups appeared to be lower than that of the control group. The histopathologic findings showed that the trabecular bone in the irradiated group had increased. The SI of the irradiated pulp tissue had decreased on T2-weighted MR images. However, the SI of the MR images in Group 2 was high in the atrophic pulp of the incisor apex at week 2 after irradiation. These patterns seen on MRI in rat bone marrow and pulp tissue were consistent with histopathologic findings. They may be useful to assess radiogenic sclerotic changes in rat mandibular bone marrow.

Finite element analysis of dental implant loading on atrophic and non-atrophic cancellous and cortical mandibular bone - a feasibility study.

Science.gov (United States)

Marcián, Petr; Borák, Libor; Valášek, Jiří; Kaiser, Jozef; Florian, Zdeněk; Wolff, Jan

2014-12-18

The first aim of this study was to assess displacements and micro-strain induced on different grades of atrophic cortical and trabecular mandibular bone by axially loaded dental implants using finite element analysis (FEA). The second aim was to assess the micro-strain induced by different implant geometries and the levels of bone-to-implant contact (BIC) on the surrounding bone. Six mandibular bone segments demonstrating different grades of mandibular bone atrophy and various bone volume fractions (from 0.149 to 0.471) were imaged using a micro-CT device. The acquired bone STL models and implant (Brånemark, Straumann, Ankylos) were merged into a three-dimensional finite elements structure. The mean displacement value for all implants was 3.1 ±1.2 µm. Displacements were lower in the group with a strong BIC. The results indicated that the maximum strain values of cortical and cancellous bone increased with lower bone density. Strain distribution is the first and foremost dependent on the shape of bone and architecture of cancellous bone. The geometry of the implant, thread patterns, grade of bone atrophy and BIC all affect the displacement and micro-strain on the mandible bone. Preoperative finite element analysis could offer improved predictability in the long-term outlook of dental implant restorations. Copyright © 2014 Elsevier Ltd. All rights reserved.

Radiomorphometric indices of mandibular bones in an 18th century population.

Science.gov (United States)

Ivanišević Malčić, Ana; Matijević, Jurica; Vodanović, Marin; Knezović Zlatarić, Dubravka; Prpić Mehičić, Goranka; Jukić, Silvana

2015-05-01

To estimate four radiomorphometric indices of mandibular bones in an 18th century population sample, and possibly associate the findings with bone mass loss related to sex, age, nutritional habits and pathologies reflecting on the bone. Thirty-six sculls (31 males, 5 females), recovered from the crypt of Požega Cathedral in Croatia were analyzed. Age estimation was based on tooth wear, and Eichner class was determined according to the number of occlusal supporting zones. The parameters in recording analogue orthopantomographs were set to constant current of 16 mA, exposure time of 14.1s, and voltage between 62-78 kV. Films were processed in an automatic dark chamber processor for 12 min, and digitized at 8-bit, 300 dpi. The thickness of the mandibular cortex was assessed below the mental foramen (MI), at antegonion (AI), at gonion (GI). Qualitative mandibular cortical index (MCI) was assessed. Average values of MI, AI and GI were 3.97 ± 0.94 mm, 2.98 ± 0.56 mm, and 1.99 ± 0.55 mm, respectively. Statistically significant differences between males and females were found for AI right (p=0.014), GI left (p=0.010) and GI average (p=0.006), and were in all cases higher in males. There were no statistically significant differences between age groups for either index (p>0.05). Considering Eichner classification the differences were not significant for MI (p=0.422), AI (p=0.516), and GI (p=0.443), but in Eichner classes II, MCI was significantly higher (p=0.02). The obtained data does not suggest generalized malnutrition or calcium, phosphorus and vitamin D deprivation in the historic population studied. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Association of Endothelin-1 Signaling with Bone Alkaline Phosphatase Expression and Protumorigenic Activities in Canine Osteosarcoma.

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Neumann, Z L; Pondenis, H C; Masyr, A; Byrum, M L; Wycislo, K L; Fan, T M

2015-01-01

Canine osteosarcoma (OS) is an aggressive sarcoma characterized by pathologic skeletal resorption and pulmonary metastases. A number of negative prognostic factors, including bone alkaline phosphatase, have been identified in dogs with OS, but the underlying biologic factors responsible for such observations have not been thoroughly investigated. Endothelin-1-mediated signaling is active during bone repair, and is responsible for osteoblast migration, survival, proliferation, and bone alkaline phosphatase expression. The endothelin-1 signaling axis is active in canine OS cells, and this pathway is utilized by malignant osteoblasts for promoting cellular migration, survival, proliferation, and bone alkaline phosphatase activities. 45 dogs with appendicular OS. The expressions of endothelin-1 and endothelin A receptor were studied in OS cell lines and in samples from spontaneously occurring tumors. Activities mediated by endothelin-1 signaling were investigated by characterizing responses in 3 OS cell lines. In 45 dogs with OS, bone alkaline phosphatase concentrations were correlated with primary tumor osteoproductivity. Canine OS cells express endothelin-1 and endothelin A receptor, and this signaling axis mediates OS migration, survival, proliferation, and bone alkaline phosphatase activities. In OS-bearing dogs, circulating bone alkaline phosphatase activities were positively correlated with primary tumor relative bone mineral densities. Canine OS cells express endothelin-1 and functional endothelin A receptors, with the potential for a protumorigenic signaling loop. Increases in bone alkaline phosphatase activity are associated with osteoblastic OS lesions, and might be an epiphenomenon of active endothelin-1 signaling or excessive osteoproduction within the localized bone microenvironment. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Mandibular Reconstruction by Using a Liquid Nitrogen-Treated Autograft in a Dog with an Oral Tumor.

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Okamura, Yasuhiko; Heishima, Kazuki; Motegi, Tomoki; Sasaki, Jun; Goryo, Masanobu; Nishida, Hideji; Tsuchiya, Hiroyuki; Katayama, Masaaki; Uzuka, Yuji

A 10 yr old intact female German shepherd dog presented with a large peripheral odontogenic fibroma and malignant melanoma on her lower jaw. The tumor was resected with a unilateral subtotal rostral hemimandibulectomy. After the mandible was removed, it was devitalized intraoperatively by freezing it in liquid nitrogen. It was subsequently reimplanted. New bone tissue formed in the gap between the frozen bone and the host bone. The regenerated bone contained osteocytes, osteoblasts, and blood vessels. The cosmetic appearance of the dog was preserved. The dog had normal mastication. The malignant melanoma recurred rostral of the left canine tooth at 159 days after the reconstruction surgery. A subtotal hemimandibulectomy was consequently performed. This is the first reported case of mandibular reconstruction using a liquid nitrogen-treated autograft in a dog with oral tumors.

Facilitation of bone resorption activities in synovial lavage fluid patients with mandibular condyle fractures.

Science.gov (United States)

Takano, H; Takahashi, T; Nakata, A; Nogami, S; Yusa, K; Kuwajima, S; Yamazaki, M; Fukuda, M

2016-05-01

The aim of this study was to investigate the bone resorption effect of the mediators delivered in joint cavity of patients with mandibular condyle fractures by detecting osteoclast markers using cellular biochemistry methods, and by analysing bone resorption activities via inducing osteoclast differentiation of the infiltrated cells from arthrocentesis. Sixteen joints in 10 patients with mandibular condyle fractures were evaluated. The control group consisted of synovial fluid (SF) samples from seven joints of four volunteers who had no clinical signs or symptoms involving the temporomandibular joint (TMJ) or disc displacement. We collected SF cells from all patients during therapeutic arthrocentesis. The infiltrating cells from TMJ SF were cultured, differentiated into tartrate-resistant acid phosphatase (TRAP)-positive osteoclast-like cells and examined bone resorption activities. We also investigated factors related to osteoclast induction of SF, using ELISA procedures. Osteoclast-like cells were induced from the SF cells obtained from all patients with condylar fractures. These multinucleated giant cells were positive for TRAP and actin, and had the ability to absorb dentin slices. The levels of macrophage colony-stimulating factor (M-CSF), prostaglandin E2 (PGE2), soluble form of receptor activator of nuclear factor kappa-B ligand (sRANKL) and osteoprotegerin (OPG), in SF samples from the patients, were significantly higher than in the controls. These findings indicate that bone resorption activities in SF from patients with mandibular condyle fractures were upregulated and may participate in the pathogenesis and wound healing. © 2016 The Authors. Journal of Oral Rehabilitation Published by John Wiley & Sons Ltd.

Evaluation of mandibular bone density to predict osteoporosis in adolescents with constitutional delayed growth

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Dural, Sema; Ozbek, Murat; Kanli, A.; Kanbur, Nuray O.; Derman, O.; Orhan, Kaan; Delilbasi, C.

2005-01-01

The aim of this study is to evaluate the correlation between constitutional delayed growth (CDG) and mandibular bone trabeculation as well as bone density on panoramic radiographs using a computer software program. Panoramic radiographs obtained from 25 patients with CDG and 25 healthy adolescents were evaluated for this study. Patients were selected from admission to Hacettepe University, Faculty of Medicine, Section of Adolescent Medicine in the first half of the year 2002. All panoramic radiographs were taken under standard conditions, and were randomized and then converted to digital images for density analysis using a scanner. The images were transferred to Osiris computer software program for the evaluation of bone density from 4 different regions on the mandible (right and left mandibular angle and condyle). The CDG group had higher values for the risk of osteoporosis considering the right (t=3.360, p=0.002) and the left condyle (t=3.620, p=0.001) (t-test for independent samples). It was also seen that the CDG group was again at higher risk in comparison to the control group when left mandibular angle values were measured (z= -2.447, p=0.014) (Mann Whitney - U test). We suggest that panoramic radiographs, which are transformed into digital format, can be valuable and economic tools for detecting the risk of osteoporosis in adolescents with CDG. (author)

Effects of occlusal inclination and loading on mandibular bone remodeling: a finite element study.

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Rungsiyakull, Chaiy; Rungsiyakull, Pimdeun; Li, Qing; Li, Wei; Swain, Michael

2011-01-01

To provide a preliminary understanding of the biomechanics with respect to the effect of cusp inclination and occlusal loading on the mandibular bone remodeling. Three different cusp inclinations (0, 10, and 30 degrees) of a ceramic crown and different occlusal loading locations (central fossa and 1- and 2-mm offsets horizontally) were taken into account to explore the stresses and strains transferred from the crown to the surrounding dental bone through the implant. A strain energy density obtained from two-dimensional plane-strain finite element analysis was used as the mechanical stimulus to drive cancellous and cortical bone remodeling in a buccolingual mandibular section. Different ceramic cusp inclinations had a significant effect on bone remodeling responses in terms of the change in the average peri-implant bone density and overall stability. The remodeling rate was relatively high in the first few months of loading and gradually decreased until reaching its equilibrium. A larger cusp inclination and horizontal offset (eg, 30 degrees and 2-mm offset) led to a higher bone remodeling rate and greater interfacial stress. The dental implant superstructure design (in terms of cusp inclination and loading location) determines the load transmission pattern and thus largely affects bone remodeling activities. Although the design with a lower cusp inclination recommended in previous studies may reduce damage and fracture failure, it could, to a certain extent, compromise bone engagement and long-term stability.

Experimental study on healing process of rat mandibular bone fracture examined by radiological procedures

International Nuclear Information System (INIS)

Iuchi, Yukio; Furumoto, Keiichi

1994-01-01

The healing process of rat mandibular fractures was stereoscopically observed daily, using plain roentgenography in the lateral-oblique and tooth axis directions and bone scintigraphy using 99m-Tc-methylene diphosphoric acid (Tc-99m-MDP). The findings were compared with microradiograms of regional polished specimens. X-ray findings included the following. Up to 3 days after bone fracture, the fracture mesiodistally showed distinct radiolucency, with sharp and irregular fracture stump. Radiopacity of the fracture site gradually increased 7 days or later, and bone trabecular formation by callus and stump bridging started to occur at 14 days. Findings similar to those in the control group were observed 49 days or later. The inside was difficult to differentiate, irrespective of the observation time. Bone scans in the mesiodistal and buccolingual planes revealed tracer uptake in the areas of mandibular and soft tissue damage one day after bone fracture. Tracer uptake began to be seen in the fracture site 3 days later, and became marked at 14 days. Then Tc-99m DMP began to be localized and returned to the findings similar to those at 49 days. Bone scanning tended to show wider areas earlier than roentgenography. Microradiographic mesiodistal examination revealed distinct radiopacy of the fracture line for 3 days after bone fracture. Seven days later, bone resorption cavity occurred in the cortical bone around the fracture stump, along with neogenesis of callus. Neogenesis and calcification began to occur gradually, and 14 days later, the fracture osteoremodeling of the internal bone trabeculae was observed. Bone trabecular formation within the bone, however, occurred later. (N.K.)

Radiographic, densitometric, and biomechanical effects of recombinant canine somatotropin in an unstable ostectomy gap model of bone healing in dogs

International Nuclear Information System (INIS)

Millis, D.L.; Wilkens, B.E.; Daniel, G.B.; Hubner, K.; Mathews, A.; Buonomo, F.C.; Patell, K.R.; Weigel, J.P.

1998-01-01

Objective: To determine the effect of recombinant canine somatotropin (STH) on radiographic, densitometric, and biomechanical aspects of bone healing using an unstable ostectomy gap model. Study Design: After an ostectomy of the midshaft radius, bone healing was evaluated over an 8-week period in control dogs (n = 4) and dogs receiving recombinant canine STH (n = 4). Animals Or Sample Population: Eight sexually intact female Beagle dogs, 4 to 5 years old. Methods: Bone healing was evaluated by qualitative and quantitative evaluation of serial radiographs every 2 weeks. Terminal dual-energy x-ray absorptiometry and three-point bending biomechanical testing were also performed. Results: Dogs receiving STH had more advanced radiographic healing of ostectomy sites. Bone area, bone mineral content, and bone density were two to five times greater at the ostectomy sites of treated dogs. Ultimate load at failure and stiffness were three and five times greater in dogs receiving STH. Conclusions: Using the ostectomy gap model, recombinant canine STH enhanced the radiographic, densitometric, and biomechanical aspects of bone healing in dogs. Clinical Relevance: Dogs at risk for delayed healing of fractures may benefit from treatment with recombinant canine STH

Comparative photoelastic study of dental and skeletal anchorages in the canine retraction

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Cristiane Aparecida de Assis Claro

2014-01-01

Full Text Available OBJECTIVE: To compare dental and skeletal anchorages in mandibular canine retraction by means of a stress distribution analysis. METHODS: A photoelastic model was produced from second molar to canine, without the first premolar, and mandibular canine retraction was simulated by a rubber band tied to two types of anchorage: dental anchorage, in the first molar attached to adjacent teeth, and skeletal anchorage with a hook simulating the mini-implant. The forces were applied 10 times and observed in a circular polariscope. The stresses located in the mandibular canine were recorded in 7 regions. The Mann-Whitney test was employed to compare the stress in each region and between both anchorage systems. The stresses in the mandibular canine periradicular regions were compared by the Kruskal-Wallis test. RESULTS: Stresses were similar in the cervical region and the middle third. In the apical third, the stresses associated with skeletal anchorage were higher than the stresses associated with dental anchorage. The results of the Kruskal-Wallis test showed that the highest stresses were identified in the cervical-distal, apical-distal, and apex regions with the use of dental anchorage, and in the apical-distal, apical-mesial, cervical-distal, and apex regions with the use of skeletal anchorage. CONCLUSIONS: The use of skeletal anchorage in canine retraction caused greater stress in the apical third than the use of dental anchorage, which indicates an intrusive component resulting from the direction of the force due to the position of the mini-implant and the bracket hook of the canine.

Compensatory canine angulation in angle Class II and III patients

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Mauro Carlos Agner Busato

2009-09-01

Full Text Available The aim of this study was to evaluate the occurence of compensation in mesiodistal axial inclinations of canines in skeletal malocclusions patients. The sample consisted of 25 Angle Class II, division 1 malocclusion (group 1 and 19 Angle Class III malocclusion patients (group 2. After measurement of dental angulations through a method that associates plaster model photography and AutoCad software, comparisons between the groups were performed by T-test for independent samples. Results showed that there was no statistically significant difference (p < 0.05 between groups, when maxillary canine angulations were compared. Regarding the mandibular canines, there was a statistically significant difference in dental angulation, expressed by 3.2° for group 1 and 0.15° for group 2. An upright position tendency for mandibular canines was observed in the Angle Class III sample. This configures a pattern of compensatory coronary positioning, since the angulation of these teeth makes them occupy less space in the dental arch and consequently mandibular incisors can be in a more retracted position in the sagittal plane.

Possibility of estimating three-dimensional mandibular morphology by cephalogram analysis

International Nuclear Information System (INIS)

Kim, S.; Motegi, Etsuko; Kikuchi, Yu; Yamaguchi, Hideharu; Takaki, Takashi; Shibahara, Takahiko

2007-01-01

The purpose of this study was to investigate the possibility of a surmise of three-dimensional mandibular morphology by two-dimensional cephalogram analysis. The materials were three-dimensional CT and cephalogram of 20 female mandibular prognathism patients (average age: 25.20±7.49) before there orthognathic surgery. Mandibular bone volume and sponge bone width were calculated from three-dimensional images constructed from CT images using imaging software (Real Intage, KGT inc.). There was a positive correlation (r=0.72) between mandibular volume value and mandibular ramus width. There was a positive correlation between sponge bone width at the site of the mandibular cuspid and mandibular ramus width and SNB angle (r=0.80), and between sponge bone width at the site of the mandibular molar and symphysis height and mandibular ramus width (r=0.81). It was thought that these results will be useful for a surmise of three-dimensional mandibular morphology by cephalogram analysis. (author)

Is the panoramic mandibular index useful for bone quality evaluation?

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Kwon, Ah Young; Huh, Kyung Hoe; Yi, Won Jin; Lee, Sam Sun; Choi, Soon Chul; Heo, Min Suk [Dept. of Oral and Maxillofacial Radiology and Dental Research Institute, School of Dentistry, Seoul National University, Seoul (United States)

2017-06-15

The aim of this study was to determine whether the panoramic mandibular index (PMI) is useful for assessing bone mineral density. We also analyzed the potential correlations between PMI parameters and patient age. Four observers measured the PMI of both sides of the mental foramen using a picture archiving and communication system and images in the Digital Imaging and Communications in Medicine format. They studied 300 panoramic radiographic images of patients belonging to the following age groups: 40–49 years, 50–59 years, 60–69 years, 70–79 years, and 80–89 years. The observers were allowed to zoom in or out and to adjust the contrast of the images. Further, they were instructed to record the reasons for any measurements that could not be made. Then, we conducted a reliability analysis of the measured PMI and assessed the correlations between different patient age groups and the 3 parameters used for determining the PMI from the available data. Among the 600 data items collected, 23 items were considered unmeasurable by at least 1 observer for the following 4 reasons: postoperative state, lesion, unidentified mental foramen, and alveolar bone loss. The intraobserver reproducibility of the measurable data was 0.611-0.752. The mandibular cortical width (MCW) decreased significantly as patient age increased. PMI had limited usability when the margin of the mental foramen was not clear. In contrast, MCW, a parameter used for determining the PMI, had fewer drawbacks than the PMI with respect to bone mineral density measurements and exhibited a significant correlation with patient age.

Is the panoramic mandibular index useful for bone quality evaluation?

International Nuclear Information System (INIS)

Kwon, Ah Young; Huh, Kyung Hoe; Yi, Won Jin; Lee, Sam Sun; Choi, Soon Chul; Heo, Min Suk

2017-01-01

The aim of this study was to determine whether the panoramic mandibular index (PMI) is useful for assessing bone mineral density. We also analyzed the potential correlations between PMI parameters and patient age. Four observers measured the PMI of both sides of the mental foramen using a picture archiving and communication system and images in the Digital Imaging and Communications in Medicine format. They studied 300 panoramic radiographic images of patients belonging to the following age groups: 40–49 years, 50–59 years, 60–69 years, 70–79 years, and 80–89 years. The observers were allowed to zoom in or out and to adjust the contrast of the images. Further, they were instructed to record the reasons for any measurements that could not be made. Then, we conducted a reliability analysis of the measured PMI and assessed the correlations between different patient age groups and the 3 parameters used for determining the PMI from the available data. Among the 600 data items collected, 23 items were considered unmeasurable by at least 1 observer for the following 4 reasons: postoperative state, lesion, unidentified mental foramen, and alveolar bone loss. The intraobserver reproducibility of the measurable data was 0.611-0.752. The mandibular cortical width (MCW) decreased significantly as patient age increased. PMI had limited usability when the margin of the mental foramen was not clear. In contrast, MCW, a parameter used for determining the PMI, had fewer drawbacks than the PMI with respect to bone mineral density measurements and exhibited a significant correlation with patient age

Effects of Recombinant Human Bone Morphogenetic Protein-2 on Vertical Bone Augmentation in a Canine Model.

Science.gov (United States)

Hsu, Yung-Ting; Al-Hezaimi, Khalid; Galindo-Moreno, Pablo; O'Valle, Francisco; Al-Rasheed, Abdulaziz; Wang, Hom-Lay

2017-09-01

Vertical bone augmentation (VBA) remains unpredictable and challenging for most clinicians. This study aims to compare hard tissue outcomes of VBA, with and without recombinant human bone morphogenetic protein (rhBMP)-2, under space-making titanium mesh in a canine model. Eleven male beagle dogs were used in the study. Experimental ridge defects were created to form atrophic ridges. VBA was performed via guided bone regeneration using titanium mesh and allografts. In experimental hemimandibles, rhBMP-2/absorbable collagen sponge was well mixed with allografts prior to procedures, whereas a control buffer was applied within controls. Dogs were euthanized after a 4-month healing period. Clinical and radiographic examinations were performed to assess ridge dimensional changes. In addition, specimens were used for microcomputed tomography (micro-CT) assessment and histologic analysis. Membrane exposure was found on five of 11 (45.5%) rhBMP-2-treated sites, whereas it was found on nine of 11 (81.8%) non-rhBMP-2-treated sites. Within 4 months of healing, rhBMP-2-treated sites showed better radiographic bone density, greater defect fill, and significantly more bone gain in ridge height (P 0.05). Under light microscope, predominant lamellar patterns were found in the specimen obtained from rhBMP-2 sites. With inherent limitations of the canine model and the concern of such a demanding surgical technique, current findings suggest that the presence of rhBMP-2 in a composite graft allows an increase of vertical gain, with formation of ectopic bone over the titanium mesh in comparison with non-rhBMP-2 sites.

Alveolar bone preservation subsequent to miniscrew implant placement in a canine model

DEFF Research Database (Denmark)

Melsen, Birte; Huja, Sarandeep; Chien, Hua-Hong

2015-01-01

Abstract OBJECTIVE: To assess the effects of transcortical screws on alveolar (bone) ridge preservation following extraction. DESIGN: Four adult beagle dogs had mandibular premolars extracted bilaterally. After 6 weeks, using a split-mouth design, two transcortical screws were inserted unilateral...

Observation of positional relation between mandibular third molars and the mandibular canal on limited cone beam computed tomography

International Nuclear Information System (INIS)

Hashizume, Atsuko; Nakagawa, Yoichi; Ishii, Hisako; Kobayashi, Kaoru

2004-01-01

We describe the preoperative use of limited cone beam computed tomography (CT) with a dental CT scanner for the assessment of mandibular third molars before extraction. Cone beam CT provides 42.7-mm-high and 30-mm-wide rectangular solid images, with a resolution of less than 0.2 mm. The positional relationship between the mandibular third molars and the mandibular canal was examined by dental CT. Sixty-eight lower third molars of 62 patients whose teeth were superimposed on the mandibular canal on periapical or panoramic radiographs were studied. Dental CT scans clearly demonstrated the positional relationship between the mandibular canal and the teeth. The mandibular canal was located buccally to the roots of 16 teeth, lingually to the roots of 27 teeth, inferiorly to the roots of 23 teeth, and between the roots of 2 teeth. The presence of bone between the mandibular canal and the teeth was not noted in 7 of 16 buccal cases, 24 of 27 lingual cases, and 10 of 23 inferior cases on dental CT scans, suggesting that the canal was in contact with the teeth. Fifty-nine of the 68 mandibular third molars were surgically removed, and postoperative transient hypoesthesia occurred in 4 patients. Dental CT scans showed no bone between the mandibular canal and the teeth in all 4 patients. Hypoesthesia was not related to the bucco-lingual location of the mandibular canal or to the extent of bone loss between the canal and the teeth. However, hypoesthesia did not occur in patients with bone between the mandibular canal and the teeth. Thus, information on the distance between the canal and teeth on dental CT scans was useful for predicting the risk of inferior alveolar nerve damage. Because of its high resolution and low radiation dose, cone beam CT was useful for examination before mandibular third molar surgery. (author)

Interrelation in the carpal bone index and orthopantomographic dental ages on the Korean children

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Ahn, Hyung Kyu; You, Dong Soo; Park, Tae Won [College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

1973-11-15

The authors have taken the x-ray films of carpal bone and orthopantomographs in Korean children to research the degree of ossification of carpal bone, that of calcification of tooth in jaw bone, the eruption rate of tooth, and the completion rate of apical foramen, and have compared the bone age with tooth age. We have gained a series of interesting conclusions to dare to report. 1. The ossification of carpal bone and the growth of tooth had processed proportionally to each other. 2. Both the bone age and tooth age were earlier in the female than in the male. 3. The completion of tooth crown formation and that of tooth root formation had processed proportionally to each other, and the general tendency of process was earliest in the mandibular first molar and the latest in the second molar. 4. The eruption of tooth was earliest in the mandibular first molar. The other teeth had erupted in the following order : the central incisor, the lateral incisor, the first premolar, the second premolar, the canine, and the second molar.

Interrelation in the carpal bone index and orthopantomographic dental ages on the Korean children

International Nuclear Information System (INIS)

Ahn, Hyung Kyu; You, Dong Soo; Park, Tae Won

1973-01-01

The authors have taken the x-ray films of carpal bone and orthopantomographs in Korean children to research the degree of ossification of carpal bone, that of calcification of tooth in jaw bone, the eruption rate of tooth, and the completion rate of apical foramen, and have compared the bone age with tooth age. We have gained a series of interesting conclusions to dare to report. 1. The ossification of carpal bone and the growth of tooth had processed proportionally to each other. 2. Both the bone age and tooth age were earlier in the female than in the male. 3. The completion of tooth crown formation and that of tooth root formation had processed proportionally to each other, and the general tendency of process was earliest in the mandibular first molar and the latest in the second molar. 4. The eruption of tooth was earliest in the mandibular first molar. The other teeth had erupted in the following order : the central incisor, the lateral incisor, the first premolar, the second premolar, the canine, and the second molar.

Prevalence of two root canals in human mandibular anterior teeth in an Iranian population

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Saeed Rahimi

2013-01-01

Full Text Available Background: Complete debridement and obturation of the root canal system is a key factor in successful endodontic treatment and the operator should therefore have thorough knowledge of the root canal morphology of the teeth. Numerous studies have been carried out to investigate the canal configuration of different tooth types in various populations. Aims: The aim of the present study was to investigate the internal anatomy of mandibular incisors and canines in an Iranian population. Materials and Methods: A total of 463 mandibular anterior teeth, including 186 centrals, 128 laterals, and 149 canines, were examined. A standard clearing technique was used to make the teeth transparent. India ink was injected into the canals of the teeth and the samples were examined with a magnifying glass. The root canal configurations were categorized according to the Vertucci classification. Results: All the incisors in this study had one root, and 12.08% of the canines had two roots. We found a slightly higher prevalence of the second canal in incisors than in canines (36.62% vs. 20.48%. However, the probability of canines having two separate apical foramina was higher than that for incisors (12.08% vs. 0.64%. Conclusions: In view of the high prevalence of two-canaled mandibular anterior teeth found in this study, it would be prudent to assume that any mandibular anterior tooth being treated is two-canaled until a thorough search proves otherwise.

Bone-anchored maxillary expansion and bilateral interoral mandibular distraction osteogenesis in adult with severe obstructive sleep apnea syndrome.

Science.gov (United States)

Nie, Ping; Zhu, Min; Lu, Xiao-Feng; Fang, Bing

2013-05-01

Severe obstructive sleep apnea syndrome (OSAS) threatens patients' lives. To solve ventilation problem, snoring, and avoid another orthognathic surgery for mandibular advancement, bone-anchored rapid maxillary expansion and bilateral interoral mandibular distraction osteogenesis were tried on a 20-year-old Chinese male patient with severe skeletal class II malocclusion and OSAS.The patient had polysomnography (apnea-hypopnea index 54.2), body mass index measurement (19.7 kg/m), and cephalometry before the treatment. Bone-anchored rapid maxillary expansion was performed for the correction of maxillary transverse and minor sagittal deficiency and the improvement of nasal airflow by decreasing nasal resistance. Bilateral interoral mandibular distraction osteogenesis was operated to lengthen the small, retruded mandible by 15 mm. Orthodontic treatment after the maxillary expansion and mandibular distraction osteogenesis can help obtain stable occlusion.The Epworth Sleepiness Scale, a questionnaire for temporomandibular joint, cephalometric analysis, polysomnography, acoustic rhinometry, and multislice spiral computed tomography were performed to evaluate changes from the treatment. All the results showed that the patient had a significantly alleviated OSAS. In addition, an acceptable occlusion was also obtained.

Bone changes in the condylar head and mandibular fossa in patients with temporomandibular disorders. Helical CT observation

International Nuclear Information System (INIS)

Shimahara, Satoru; Ariyoshi, Yasunori; Kimura, Yoshihiro; Shimahara, Masashi

2011-01-01

In the present study, we investigated whether bone changes are present in sites impossible to observe by panoramic X-ray and Schuller's X-ray examination, namely the medial of the condylar head and mandibular fossa, in patients with type IV temporomandibular joint disorders. We observed the articular fossa using computed tomography, which is able to obtain detailed 3-dimensional information, in patients with type IV temporomandibular disorders. We examined 120 joints of 60 patiens who visited the Department of Oral Surgery, Osaka Medical College Hospital. Each condylar head was clearly visualized in panoramic X-ray and Schuller's X-ray examination findings, and shown to have possible changes unilaterally. Each joint was diagnosed as type IV, according to the diagnostic guidelines set by Japanese Society for Temporomandibular Joint, and further examined using helical CT. Changes in condylar head; We concluded that bone changes were present with considerable probability in the medial of condylar head in a manner similar to those found in the lateral and center of joints with type IV temporomandibular disorders. Changes in mandibular fossa; The bone changes occurred in various locations of the mandibular fossa, while they appeared significantly more frequently in the condylar head. We think that our finding will contribute to development of treatment strategies for temporomandibular disorders, as they clarify bone changes in sites previously unreported. (author)

Microangiographic study of the canine dental tissues: a preliminary report

International Nuclear Information System (INIS)

Miyabayashi, T.; Morgan, J.P.

1987-01-01

A microangiographic study of the dental tissues was performed on one adult mongrel dog to examine the usefulness of the technique. This preliminary study used 30% wt/vol Micropaque suspension which was perfused into the common carotid arteries. After the complete perfusion, the specimen was fixed into a mixture of 10% buffered neutral formalin solution and 95% ethyl alcohol. The mandibular bone with teeth in situ was decalcified. The specimen was embedded in methyl methacrylate. One mm slab sections were made, and then the microangiographs were made. Adequate filling of arterioles was evident on the microangiographs. This technique is shown to be useful in characterizing the nature of the blood supply to the bone and teeth that might be involved in the pathogenesis of radiation-induced injury in the canine dental and periodontal tissues

Restoration of a vertical alveolar bone defect by orthodontic relocation of a mesially impacted mandibular first molar.

Science.gov (United States)

Kim, Sung-Jin; Kim, Jin-Wook; Choi, Tae-Hyun; Lee, Kee-Joon

2015-04-01

An impacted mandibular first molar tends to cause serious bone defects of the adjacent teeth. When choosing between the 2 typical treatment options-extraction or orthodontic relocation of the impacted tooth-the decision should be based on assessment of the prognosis. A 22-year-old man with severe mesioangulation and impaction of the mandibular first molar and a related vertical bone defect on the distal side of the second premolar was treated with extraction of the second molar and orthodontic relocation of the first molar with a retromolar miniscrew. Comprehensive orthodontic treatment involving premolar extraction was conducted. Strategic extraction of the molar and adequate orthodontic movement helped to restore the bone structure on the affected side. This case report suggests the effectiveness of restoration of bone defects by using viable periodontal tissues around the impacted tooth for the longevity of the periodontium. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Mandibular Bone and Soft Tissues Necrosis Caused by an Arsenical Endodontic Preparation Treated with Piezoelectric Device

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A. Giudice

2013-01-01

Full Text Available This paper describes a case of wide mandibular bone necrosis associated with significant soft tissues injury after using an arsenical endodontic preparation in the right lower second molar for endodontic purpose. Authors debate about the hazardous effects of the arsenic paste and the usefulness of piezosurgery for treatment of this drug related bone necrosis.

Angiographic findings of demineralised bone matrix grafts in femoral fracture repair in canines*

International Nuclear Information System (INIS)

Kumar, R.V.S.; Ramakrishna, O.

2000-01-01

Demineralised bone matrix implants and autogenous cancellous bone grafts were evaluated in femoral fracture repair with bone loss in canines, and compared to untreated animals. Angiograms were taken at 3,6,9 and 12 weeks post- operatively using conrary-420 as contrast medium. Early angiograms showed leakage of contrast medium into soft tissue. Grafted groups showed slight hypervascularity and enhanced capillary network. At 12 Weeks the same groups observed nearly normal persistent vascular supply. Early establishment of cortices continuity and draining of contrast medium via extraosseous veins was observed in demineralized bone matrix implanted groups

Radiography of the mandible prior to endosseous implant treatment. Localization of the mandibular canal and assessment of trabecular bone

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Lindh, C.

1996-03-01

Mandibular autopsy specimens were examined with different radiographic techniques in order to evaluate the visibility of the mandibular canal and the measurement accuracy of distances related to the mandibular canal. Hypocycloidal, spiral and computed tomography (CT) were superior to periapical and panoramic radiography in visualizing the mandibular canal. The tomographic techniques were more accurate when measurements of distances related to the mandibular canal were performed. No difference in measurement accuracy was found between the tomographic techniques. Concerning visibility of the mandibular canal, interobserver agreement was lowest for periapical radiography and highest for CT. Intraobserver agreement was moderate or good for all techniques. A high interobserver variation was found for measurability of distances related to the mandibular canal. The trabecular bone tissue in mandibular autopsy specimens was studied concerning different characteristics. A classification system to be used prior to implant treatment, based on the trabecular pattern in periapical radiographs, was proposed. 74 refs.

Radiography of the mandible prior to endosseous implant treatment. Localization of the mandibular canal and assessment of trabecular bone

International Nuclear Information System (INIS)

Lindh, C.

1996-03-01

Mandibular autopsy specimens were examined with different radiographic techniques in order to evaluate the visibility of the mandibular canal and the measurement accuracy of distances related to the mandibular canal. Hypocycloidal, spiral and computed tomography (CT) were superior to periapical and panoramic radiography in visualizing the mandibular canal. The tomographic techniques were more accurate when measurements of distances related to the mandibular canal were performed. No difference in measurement accuracy was found between the tomographic techniques. Concerning visibility of the mandibular canal, interobserver agreement was lowest for periapical radiography and highest for CT. Intraobserver agreement was moderate or good for all techniques. A high interobserver variation was found for measurability of distances related to the mandibular canal. The trabecular bone tissue in mandibular autopsy specimens was studied concerning different characteristics. A classification system to be used prior to implant treatment, based on the trabecular pattern in periapical radiographs, was proposed. 74 refs

Asymmetry in development (mineralisation of permanent mandibular canine roots

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Burić Mirjana V.

2012-01-01

Full Text Available Introduction. The development of the teeth is closely associated with the proper and unobstructed physical and psychological development of the child. Aim. To determine the existence of asymmetry in the development of the roots of the lower permanent canine teeth in different age groups of children of both sexes. Material and methods. The study was conducted on 523 ortopantomograms (253 boys and 270 girls of orthodontic patients aged 6 to 14 years of the Dental Clinic in Niš. We analyzed the development of asymmetry in the lower permanent canine root, using the method of Gleiser and Hunt, or the modification by Tijanić (1981. Results. It was found that asymmetry in the development of the root in both sexes of the lower canine teeth was present in 20 patients (3.82%, 10 boys (3.95% and 10 girls (3.70%. The difference is in the range of one stage. Asymmetric development of the roots of the lower incisors in girls and boys usually present in the 7th and 8th stages (60% in girls and in 50% in boys. In 90% of girls in developing asymmetry the root of the lower canine is present in a single stage, and in 10% of girls it presents within three stages. Asymmetric development of the root of the lower canine is the most common in the 7th and 8th stages of development (55%. Conclusion. Asymmetric root development of permanent lower canines was found in 3.82% of patients. More than half of respondents (55% had asymmetrical canine root development stage in half and three quarters of the total root length. The results of this study indicate that the canine is the tooth with very little variations in its development.

[Bone graft reconstruction for posterior mandibular segment using the formwork technique].

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Pascual, D; Roig, R; Chossegros, C

2014-04-01

Pre-implant bone graft in posterior mandibular segments is difficult because of masticatory and lingual mechanical constraints, because of the limited bone vascularization, and because of the difficulty to cover it with the mucosa. The formwork technique is especially well adapted to this topography. The recipient site is abraded with a drill. Grooves are created to receive and stabilize the grafts. The bone grafts were harvested from the ramus. The thinned cortices are assembled in a formwork and synthesized by mini-plates. The gaps are filled by bone powder collected during bone harvesting. The bone volume reconstructed with the formwork technique allows anchoring implants more than 8mm long. The proximity of the inferior alveolar nerve does not contra indicate this technique. The formwork size and its positioning on the alveolar crest can be adapted to prosthetic requirements by using osteosynthesis plates. The lateral implant walls are supported by the formwork cortices; the implant apex is anchored on the native alveolar crest. The primary stability of implants is high, and the torque is important. The ramus harvesting decreases operative risks. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

The use of lyophilised bovine bone xenograft in mandibular reconstructive surgery - an animal experimental surgery

International Nuclear Information System (INIS)

Samsudin, A.R.; Meor Kamal, M. Z.; Afifi Abu Bakar

1999-01-01

The aim of this study is to look at the effectiveness of using lyophillised bovine bone xenograft in mandibular reconstructive surgery. Six adult merino sheep underwent bilateral marginal block resection of the mandible under general anaesthesia. The defect on the right body of mandible was left alone while the similar mandibulectomy defect on the left body of mandible was reconstructed using a cortico-cancellous block of radiosterilised lyophillised bovine bone xenograft which was procured from a calve femur. The bone xenograft was fixed and immobilized using titanium mini plates and screws. All the sheep returned to the controlled grazing ground on the 7th. Postoperative day. One sheep was sacrificed every month and the mandible was retrieved for postmortem gross and microscopical histological examination. Clinical results showed no evidence of tissue rejection in the mandible of the sheep and all the wounds healed well. All sheep showed no problem with normal eating habits. Histological examination showed resorption of the xenograft very early at one month postoperative and xenograft resorption together with new host bone deposition started at 2 months postoperative and maximise at 6 months postoperative. There is also evidence showing that the cancellous portion resorp more than the cortical portion of the xenograft. In conclusion, cortico-cancellous blocks of bovine bone xenograft may be use in mandibular reconstructive surgery giving esthetically acceptable, functional, biocompatible and overall clinically predictable results

Enhancement of osteogenesis and biodegradation control by brushite coating on Mg-Nd-Zn-Zr alloy for mandibular bone repair.

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Guan, Xingmin; Xiong, Meiping; Zeng, Feiyue; Xu, Bin; Yang, Lingdi; Guo, Han; Niu, Jialin; Zhang, Jian; Chen, Chenxin; Pei, Jia; Huang, Hua; Yuan, Guangyin

2014-12-10

To diminish incongruity between bone regeneration and biodegradation of implant magnesium alloy applied for mandibular bone repair, a brushite coating was deposited on a matrix of a Mg-Nd-Zn-Zr (hereafter, denoted as JDBM) alloy to control the degradation rate of the implant and enhance osteogenesis of the mandible bone. Both in vitro and in vivo evaluations were carried out in the present work. Viability and adhesion assays of rabbit bone marrow mesenchyal stem cells (rBM-MSCs) were applied to determine the biocompatibility of a brushite-coated JDBM alloy. Osteogenic gene expression was characterized by quantitative real-time polymerase chain reaction (RT-PCR). Brushite-coated JDBM screws were implanted into mandible bones of rabbits for 1, 4, and 7 months, respectively, using 316L stainless steel screws as a control group. In vivo biodegradation rate was determined by synchrotron radiation X-ray microtomography, and osteogenesis was observed and evaluated using Van Gieson's picric acid-fuchsin. Both the naked JDBM and brushite-coated JDBM samples revealed adequate biosafety and biocompatibility as bone repair substitutes. In vitro results showed that brushite-coated JDBM considerably induced osteogenic differentiation of rBM-MSCs. And in vivo experiments indicated that brushite-coated JDBM screws presented advantages in osteoconductivity and osteogenesis of mandible bone of rabbits. Degradation rate was suppressed at a lower level at the initial stage of implantation when new bone tissue formed. Brushite, which can enhance oeteogenesis and partly control the degradation rate of an implant, is an appropriate coating for JDBM alloys used for mandibular repair. The Mg-Nd-Zn-Zr alloy with brushite coating possesses great potential for clinical applications for mandibular repair.

Scapular Free Vascularised Bone Flaps for Mandibular Reconstruction: Are Dental Implants Possible?

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Martin Lanzer

2015-09-01

Full Text Available Objectives: Free fibula flap remains the flap of choice for reconstruction of mandibular defects. If free fibula flap is not possible, the subscapular system of flaps is a valid option. In this study, we evaluated the possibility of dental implant placement in patients receiving a scapular free flap for oromandibular reconstruction. Material and Methods: We retrospectively reviewed 10 patients undergoing mandible reconstruction with a subscapular system free-tissue (lateral border of the scapula transfer at the University Hospital Zürich between January 1, 2010 and January 1, 2013. Bone density in cortical and cancellous bone was measured in Hounsfield units (HU. Changes of bone density, height and width were analysed using IBM SPSS Statistics 22. Comparisons of bone dimensions as well as bone density were performed using a chi-square test. Results: Ten patients were included. Implantation was conducted in 50%. However, all patients could have received dental implants considering bone stock. Loss of bone height and width were significant (P < 0.001. There was a statistical significant increase in bone density in cortical (P < 0.001 and cancellous (P = 0.004 bone. Conclusions: Dental implants are possible after scapular free flap reconstruction of oromandibular defects. Bone height and width were reduced, while bone density increased with time.

Mathematical equation for prediction of cat mandibular canal height dimension based on canine tooth width measurement.

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Santos, Miguel; Carreira, L Miguel

2016-06-01

The present study was performed in a sample of 33 cats and aimed (1) to characterise the mandible height (Mh), mandibular canal height (MCh) and the distance between the interdental alveolar margin and the mandibular canal (dIAM-MC); and (2) to develop a mathematical model for dimension prediction of MCh using the patient's age, weight (Wg) and canine tooth width at the free gingival margin level (wCGM) that was easily accessible during the oral examination. Age, sex, breed, weight, skull type and the wCGM were the recorded variables for each patient. Right and left lateral view skull radiographs were made followed by measurements of the mandible anatomical structures, taken between the third premolar distal root and the fourth premolar proximal root. Results were considered statistically significant for P values <0.05, and statistical analysis was performed using SPSS software. We observed a strong correlation only between wCGM and MCh, and a prediction mathematical model was developed to calculate the MCh, with a standard error of only 0.4 mm. Our study allows a surgeon to establish relationships between a physical parameter, such as wCGM, evaluated in an oral examination, and the mandibular canal, which is a very important anatomical structure to consider in surgical procedures. Ideally, surgeons should always plan their mandible work only after obtaining a final diagnosis achieved through the use of complementary imaging exams, such as intra- and extra-oral radiographs. Thus, this mathematical equation offers an additional tool, providing more information on the relationships between oral anatomical structures, reducing the risk of iatrogenic lesions and promoting patient safety. © ISFM and AAFP 2015.

Evaluation of secondary alveolar bone grafting outcomes performed after canine eruption in complete unilateral cleft lip and palate.

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Lorenzoni, Diego Coelho; Janson, Guilherme; Bastos, Juliana Cunha; Carvalho, Roberta Martinelli; Bastos, José Carlos; de Cássia Moura Carvalho Lauris, Rita; Henriques, José Fernando Castanha; Ozawa, Terumi Okada

2017-01-01

Evaluate the results of secondary alveolar bone grafting (SABG) in patients with complete unilateral cleft lip and palate (UCLP), operated after permanent canine eruption (CE). Seventy-four periapical radiographs from patients with complete UCLP (mean age 14 years) submitted to SABG were retrospectively analyzed for the amount of bone in the cleft site through the Bergland and Chelsea scales. Of the cases, 47.3 % was classified as Bergland type I and Chelsea type A, 35.2 % as type II/C, 6.7 % as type III/D, and 10.8 % as type IV/failure. When the canine was moved into the grafted area, the success rate (type I/A) was 56.8 %; for cases in which the space was maintained for an implant or prosthetic finishing, the index was 45.8 %; however, this difference was not statistically significant. Even in advanced ages, after permanent canine eruption, SABG can be considered a highly successful procedure. This research shows good results of secondary alveolar bone grafting performed in patients with unilateral complete cleft lip and palate, even when it was performed after eruption of the permanent canine in the cleft area.

Bone Regeneration of Hydroxyapatite with Granular Form or Porous Scaffold in Canine Alveolar Sockets

Science.gov (United States)

JANG, SEOK JIN; KIM, SE EUN; HAN, TAE SUNG; SON, JUN SIK; KANG, SEONG SOO; CHOI, SEOK HWA

2017-01-01

This study was undertaken to assess bone regeneration using hydroxyapatite (HA). The primary focus was comparison of bone regeneration between granular HA (gHA) forms and porous HA (pHA) scaffold. The extracted canine alveolar sockets were divided with three groups: control, gHA and pHA. Osteogenic effect in the gHA and pHA groups showed bone-specific surface and bone mineral density to be significantly higher than that of the control group (psocket healing. For new bone formation during 8 weeks' post-implantation, HA with porous scaffold was superior to the granular form of HA. PMID:28438860

Radiological study of the mandibular fractures

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Kim, Ju Won; Kim, Kyoung A; Koh, Kwang Jun [Department of Oral and Maxillofacial Radiology, School of Dentistry, and Institute of Oral Bio Science, Chonbuk National University, Jeonju (Korea, Republic of)

2009-06-15

To classify and evaluate mandibular fractures. The author classified mandibular fractures of 284 patients who were referred to the Chonbuk National University Dental Hospital during the period from March 2004 to June 2007. This study was based on the conventional radiographs as well as computed tomographs which were pertained to the 284 patients who have had the mandibular fractures including the facial bone fractures. And mandibular fractures were classified with respect to gender, age, site and type of the fractures. More frequently affected gender with mandibular fracture was male with the ratio of 3.3 : 1. The most frequently affected age with mandibular fracture was third decade (38%), followed by fourth decade (16%), second decade (15%), fifth decade (11%), sixth decade (7%), seventh decade (5%), eighth decade (4%), first decade (4%), and ninth decade (0.3%). The most frequent type of mandibular fracture was single fracture (58%), followed by double fracture (39%), triple fracture (3%). The most common site of mandibular fracture was mandibular condyle as 113 cases (27.7%) and the next was mandibular symphysis as 109 cases (26.7%), mandibular angle as 103 cases (25.3%), mandibular body as 83 cases (20.3%) in order. The sum of fracture sites were 408 sites and there were 1.4 fracture sites per one patient. The number of mandible fractures accompanied with facial bone fractures were 41 cases (14.4%). The results showed the most frequent type and common site of mandibular fracture was single fracture and mandibular condyle respectively.

Radiological study of the mandibular fractures

International Nuclear Information System (INIS)

Kim, Ju Won; Kim, Kyoung A; Koh, Kwang Jun

2009-01-01

To classify and evaluate mandibular fractures. The author classified mandibular fractures of 284 patients who were referred to the Chonbuk National University Dental Hospital during the period from March 2004 to June 2007. This study was based on the conventional radiographs as well as computed tomographs which were pertained to the 284 patients who have had the mandibular fractures including the facial bone fractures. And mandibular fractures were classified with respect to gender, age, site and type of the fractures. More frequently affected gender with mandibular fracture was male with the ratio of 3.3 : 1. The most frequently affected age with mandibular fracture was third decade (38%), followed by fourth decade (16%), second decade (15%), fifth decade (11%), sixth decade (7%), seventh decade (5%), eighth decade (4%), first decade (4%), and ninth decade (0.3%). The most frequent type of mandibular fracture was single fracture (58%), followed by double fracture (39%), triple fracture (3%). The most common site of mandibular fracture was mandibular condyle as 113 cases (27.7%) and the next was mandibular symphysis as 109 cases (26.7%), mandibular angle as 103 cases (25.3%), mandibular body as 83 cases (20.3%) in order. The sum of fracture sites were 408 sites and there were 1.4 fracture sites per one patient. The number of mandible fractures accompanied with facial bone fractures were 41 cases (14.4%). The results showed the most frequent type and common site of mandibular fracture was single fracture and mandibular condyle respectively.

Ultrasound to stimulate mandibular bone defect healing : A placebo-controlled single-blind study in rats

NARCIS (Netherlands)

Schortinghuis, J; Ruben, JL; Raghoebar, GM; Stegenga, B

Purpose: Because of the limitations of the body to heal large maxillofacial bone defects, an attempt was made to stimulate mandibular defect healing with low intensity pulsed ultrasound in rats. This ultrasound consists of a 1.5-MHz pressure wave administered in pulses of 200 musec, with an average

Quantitation of mandibular symphysis volume as a source of bone grafting.

Science.gov (United States)

Verdugo, Fernando; Simonian, Krikor; Smith McDonald, Roberto; Nowzari, Hessam

2010-06-01

Autogenous intramembranous bone graft present several advantages such as minimal resorption and high concentration of bone morphogenetic proteins. A method for measuring the amount of bone that can be harvested from the symphysis area has not been reported in real patients. The aim of the present study was to intrasurgically quantitate the volume of the symphysis bone graft that can be safely harvested in live patients and compare it with AutoCAD (version 16.0, Autodesk, Inc., San Rafael, CA, USA) tomographic calculations. AutoCAD software program quantitated symphysis bone graft in 40 patients using computerized tomographies. Direct intrasurgical measurements were recorded thereafter and compared with AutoCAD data. The bone volume was measured at the recipient sites of a subgroup of 10 patients, 6 months post sinus augmentation. The volume of bone graft measured by AutoCAD averaged 1.4 mL (SD 0.6 mL, range: 0.5-2.7 mL). The volume of bone graft measured intrasurgically averaged 2.3 mL (SD 0.4 mL, range 1.7-2.8 mL). The statistical difference between the two measurement methods was significant. The bone volume measured at the recipient sites 6 months post sinus augmentation averaged 1.9 mL (SD 0.3 mL, range 1.3-2.6 mL) with a mean loss of 0.4 mL. AutoCAD did not overestimate the volume of bone that can be safely harvested from the mandibular symphysis. The use of the design software program may improve surgical treatment planning prior to sinus augmentation.

Quantitative CBCT evaluation of maxillary and mandibular cortical bone thickness and density variability for orthodontic miniplate placement.

Science.gov (United States)

Rossi, Margherita; Bruno, Giovanni; De Stefani, Alberto; Perri, Alessandro; Gracco, Antonio

2017-12-01

To assess whether cortical bone thickness and density vary in relation to age, sex and skeletal pattern at the maxillary and mandibular areas suitable for miniplates placement for orthodontic purposes. CBCT of 92 subjects (42 males and 50 females) with skeletal class I, II or III malocclusion, divided between adolescents and adults, were examined. InVivoDental ® software (Anatomage Inc, USA) was used to measure 34 maxillary areas and 40 mandibular areas per side. Values obtained were then compared between the groups of subjects. Statistical analysis was performed using the non-parametric Wilcoxon-Mann-Whitney rank-sum test for independent samples. No significant differences were found in the cortical bone thickness values between the three skeletal patterns, and according to sex and age. Both maxilla and mandible showed an increase in cortical bone thickness from the anterior towards the posterior regions, and from the alveolar boneto the basal bone. Cortical bone density significantly varied in relation to the subject's age, with adults always showing higher values. Slight clinically significant differences were found between the three skeletal patterns and sex. In terms of cortical bone thickness, age, sex and skeletal pattern do not represent valid decision criteria for the evaluation of the best insertion areas for miniplates, while in terms of cortical bone density, only age is useful as a decision criterion. Copyright © 2017 CEO. Published by Elsevier Masson SAS. All rights reserved.

A new technique for mandibular osteotomy

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Puricelli Edela

2007-03-01

Full Text Available Abstract Sagittal split osteotomy (SSO is a surgical technique largely employed for mandibular mobilizations in orthognatic procedures. However, the traditional design of buccal osteotomy, located at the junction of mandibular ramus and body, may prevent more extensive sliding between the bone segments, particularly on the advance, laterality and verticality of the mandibular body. The author proposes a new technical and conceptual solution, in which osteotomy is performed in a more distal region, next to the mental formamen. Technically, the area of contact between medullary-cancellous bone surfaces is increased, resulting in larger sliding rates among bone segments; it also facilitates the use of rigid fixation systems, with miniplates and monocortical screws. Conceptually, it interferes with the resistance arm of the mandible, seen as an interpotent lever of the third gender.

Evaluation of mRNA expression levels and electrophysiological function of neuron-like cells derived from canine bone marrow stromal cells.

Science.gov (United States)

Nakano, Rei; Edamura, Kazuya; Sugiya, Hiroshi; Narita, Takanori; Okabayashi, Ken; Moritomo, Tadaaki; Teshima, Kenji; Asano, Kazushi; Nakayama, Tomohiro

2013-10-01

To investigate the in vitro differentiation of canine bone marrow stromal cells (BMSCs) into functional, mature neurons. Bone marrow from 6 adult dogs. BMSCs were isolated from bone marrow and chemically induced to develop into neurons. The morphology of the BMSCs during neuronal induction was monitored, and immunocytochemical analyses for neuron markers were performed after the induction. Real-time PCR methods were used to evaluate the mRNA expression levels of markers for neural stem or progenitor cells, neurons, and ion channels, and western blotting was used to assess the expression of neuronal proteins before and after neuronal induction. The electrophysiological properties of the neuron-like cells induced from canine BMSCs were evaluated with fluorescent dye to monitor Ca(2)+ influx. Canine BMSCs developed a neuron-like morphology after neuronal induction. Immunocytochemical analysis revealed that these neuron-like cells were positive for neuron markers. After induction, the cells' mRNA expression levels of almost all neuron and ion channel markers increased, and the protein expression levels of nestin and neurofilament-L increased significantly. However, the neuron-like cells derived from canine BMSCs did not have the Ca(2)+ influx characteristic of spiking neurons. Although canine BMSCs had neuron-like morphological and biochemical properties after induction, they did not develop the electrophysiological characteristics of neurons. Thus, these results have suggested that canine BMSCs could have the capacity to differentiate into a neuronal lineage, but the differentiation protocol used may have been insufficient to induce development into functional neurons.

A study on the healing process of bone defect-examination of healing stages of bone defect in the irradiated mandibular rim by microradiography and autoradiography

International Nuclear Information System (INIS)

Shimoyama, Tetsuo

1980-01-01

The mandibular rim of 150 female Donryu strain rats was exposed to 2000 rads (B group) or to 3000 rads (C group), and a bone defect of 1 x 1 x 2 mm in size was formed in the madibular rim. Cure process of this bone defect was observed periodically by microradiography and autoradiography using 45 Ca as a tracer, compared with that in the control group (A group, non-irradiated). Irradiated rats having bone defects recovered smoothly. Microradiographic findings of the A group showed that new bone was formed on the surface of the perosteum of the mandible on the 7th days after the irradiation. Bone defects in all rats were repaired completely by the 49th days after the irradiation. Microradiographic findings of the B and C groups showed that new bone was formed on the tongue side surface of the periosteum of the mandible in the early stage after the irradiation. However, after that, osteogenesis became slower, and the edge of bone defects or a part of the mandible became smaller. Bone defects were not repaired and became larger. These findings were more marked in the C group than in the B group. Autoradiographic findings showed marked uptake of 45 Ca into new bone in the A group. Rats of which bone defects were repaired showed the uptake of 45 Ca in accordance with the shape of the mandibular rim. The edge of bone defect of the B and C groups where new bone was not formed was destroyed since the 14th day after the irradiation. There were some cases in which the uptake of 45 Ca into the surface of the periosteum of the mandible near bone defect was observed even when bone defect was enlarged. (Tsunoda, M.)

Impact of balancing-side tooth contact on clenching induced mandibular displacements in humans.

Science.gov (United States)

Baba, K; Yugami, K; Yaka, T; Ai, M

2001-08-01

This study investigated mandibular displacements during clenching in the lateral mandibular position in relation to lateral occlusal relationships. Twelve healthy human subjects (mean=26.7 years) volunteered for this study. Acrylic occlusal devices were fabricated for the lower working-side canine, working-side second molar and balancing-side second molar in order to simulate a dominant canine guidance, working-side interference (WI), balancing-side interference (BI) and bilateral balanced occlusion (BO). Vertical displacements of the mandible were recorded by linear variable differential transformers during submaximal clenching in the right lateral position. The four experimental occlusal conditions were revealed to have a significant effect on mandibular displacement patterns (ANOVA, P experimental conditions. These results suggest that the nature of reaction forces at the temporomandibular (TM) joints caused by the elevation of the mandible varies in a predictable manner depending upon lateral occlusal relationships.

Biological behaviour of canine mandibular osteosarcoma. A retrospective study of 50 cases (1999-2007).

Science.gov (United States)

Coyle, V J; Rassnick, K M; Borst, L B; Rodriguez, C O; Northrup, N C; Fan, T M; Garrett, L D

2015-06-01

The purpose of this retrospective study was to describe the biological behaviour of canine mandibular osteosarcoma (OSA) and to examine factors for their impact on metastasis-free interval (MFI) and survival time (ST). Records from dogs treated with mandibulectomy for OSA (1999-2007) were reviewed. Archived tumour samples were evaluated for mitotic index (MI) and tumour grade. Fifty dogs were included, 21 received chemotherapy. Twenty-nine dogs (58%) developed metastatic disease. The median MFI was 627 days, and median ST was 525 days. In univariate analysis MI > 40 was prognostic for decreased MFI and ST. Grade also influenced MFI and ST, with 5/21 (24%) dogs with grade II/III tumours metastasis-free at one year versus 16/22 (72%) dogs with grade I tumours (P = 0.002); and 5/21 (24%) dogs with grade II/III tumours alive versus 17/22 (77%) dogs with grade I tumours (P = 0.001). In multivariate analysis, histological grade and adjuvant chemotherapy were prognostic for MFI and ST. © 2013 Blackwell Publishing Ltd.

Disimpaction of maxillary canines using temporary bone anchorage and cantilever springs.

Science.gov (United States)

Thebault, Benoit; Dutertre, Eric

2015-03-01

Impacted canines, particularly in the maxilla, are frequently encountered in orthodontic practice. Unfortunately, depending on their position, correction can often be difficult and sometimes unsuccessful. Thorough diagnosis along with orthodontic treatment combining bone-supported anchorage and cantilever springs appears, in our view, to offer the best solution to this tricky orthodontic challenge while limiting, as far as possible, the risk of failure. Copyright © 2015. Published by Elsevier Masson SAS.

Reconstruction of the mandible bone by treatment of resected bone with pasteurization.

Science.gov (United States)

Uehara, Masataka; Inokuchi, Tsugio; Sano, Kazuo; Sumita, Yoshinori; Tominaga, Kazuhiro; Asahina, Izumi

2012-11-01

The results of long-term follow-up for reimplantation of the mandibular bone treated with pasteurization are reported. Mandibulectomy was performed for mandibular malignancy in 3 cases. The resected bones were subsequently reimplanted after treatment with pasteurization in 3 cases to eradicate tumor cells involved in the resected bone. Although postoperative infection was observed in 2 of 3 cases, reimplantation of the resected mandibular bone treated by pasteurization was finally successful. Ten to 22 years of follow-up was carried out. Pasteurization was able to devitalize tumor cells involved in the resected bone and to preserve bone-inductive activity. Reimplantation of pasteurization could be a useful strategy for reconstruction of the mandible in patients with mandibular malignancy.

Large Bone Vertical Augmentation Using a Three-Dimensional Printed TCP/HA Bone Graft: A Pilot Study in Dog Mandible.

Science.gov (United States)

Carrel, Jean-Pierre; Wiskott, Anselm; Scherrer, Susanne; Durual, Stéphane

2016-12-01

Osteoflux is a three-dimensional printed calcium phosphate porous structure for oral bone augmentation. It is a mechanically stable scaffold with a well-defined interconnectivity and can be readily shaped to conform to the bone bed's morphology. An animal experiment is reported whose aim was to assess the performance and safety of the scaffold in promoting vertical growth of cortical bone in the mandible. Four three-dimensional blocks (10 mm length, 5 mm width, 5 mm height) were affixed to edentulous segments of the dog's mandible and covered by a collagen membrane. During bone bed preparation, particular attention was paid not to create defects 0.5 mm or more so that the real potential of the three-dimensional block in driving vertical bone growth can be assessed. Histomorphometric analyses were performed after 8 weeks. At 8 weeks, the three-dimensional blocks led to substantial vertical bone growth up to 4.5 mm from the bone bed. Between 0 and 1 mm in height, 44% of the surface was filled with new bone, at 1 to 3 mm it was 20% to 35%, 18% at 3 to 4, and ca. 6% beyond 4 mm. New bone was evenly distributed along in mesio-distal direction and formed a new crest contour in harmony with the natural mandibular shape. After two months of healing, the three-dimensional printed blocks conducted new bone growth above its natural bed, up to 4.5 mm in a canine mandibular model. Furthermore, the new bone was evenly distributed in height and density along the block. These results are very promising and need to be further evaluated by a complete powerful study using the same model. © 2016 Wiley Periodicals, Inc.

Combined surgical management of mandibular angle prominence and microgenia

International Nuclear Information System (INIS)

Portelles Masso, Ayelen Maria; Berger Kohn, Carlos

2010-01-01

Chin play a very important role in facial aesthetics. Different deformities of volume and of position may occur at this level and it is the microgenia one of the more frequent. Treatment options include the use of silicone, alloplasty materials and autologous bone graft. Authors report the use of the bone removed from mandibular angle to increase the chin. This is the case of a white female patient aged 18 seen by the Orthognathics Multidisciplinary Staff of 'V. I. Lenin' Hospital due to its uncommon face width. The corresponding physical examination as well as the complementary ones diagnosed a bilateral prominence of mandibular angle associated with a microgenia. Surgery carried out was of remodeling type of both mandibular angles and genioplasty of height increase and a discrete advancement using the bone removed from the gonion. There were satisfactory aesthetic results without evidence of bone reabsorption. We conclude that use of autologous graft of mandibular angle is an effective treatment alternative for correction of microgenia. (author)

Radiological Assessment of Bioengineered Bone in a Muscle Flap for the Reconstruction of Critical-Size Mandibular Defect

Science.gov (United States)

Al-Fotawei, Randa; Ayoub, Ashraf F.; Heath, Neil; Naudi, Kurt B.; Tanner, K. Elizabeth; Dalby, Matthew J.; McMahon, Jeremy

2014-01-01

This study presents a comprehensive radiographic evaluation of bone regeneration within a pedicled muscle flap for the reconstruction of critical size mandibular defect. The surgical defect (20 mm×15 mm) was created in the mandible of ten experimental rabbits. The masseter muscle was adapted to fill the surgical defect, a combination of calcium sulphate/hydroxyapatite cement (CERAMENT™ |SPINE SUPPORT), BMP-7 and rabbit mesenchymal stromal cells (rMSCs) was injected inside the muscle tissue. Radiographic assessment was carried out on the day of surgery and at 4, 8, and 12 weeks postoperatively. At 12 weeks, the animals were sacrificed and cone beam computerized tomography (CBCT) scanning and micro-computed tomography (µ-CT) were carried out. Clinically, a clear layer of bone tissue was identified closely adherent to the border of the surgical defect. Sporadic radio-opaque areas within the surgical defect were detected radiographically. In comparison with the opposite non operated control side, the estimated quantitative scoring of the radio-opacity was 46.6% ±15, the mean volume of the radio-opaque areas was 63.4% ±20. Areas of a bone density higher than that of the mandibular bone (+35% ±25%) were detected at the borders of the surgical defect. The micro-CT analysis revealed thinner trabeculae of the regenerated bone with a more condensed trabecular pattern than the surrounding native bone. These findings suggest a rapid deposition rate of the mineralised tissue and an active remodelling process of the newly regenerated bone within the muscle flap. The novel surgical model of this study has potential clinical application; the assessment of bone regeneration using the presented radiolographic protocol is descriptive and comprehensive. The findings of this research confirm the remarkable potential of local muscle flaps as local bioreactors to induce bone formation for reconstruction of maxillofacial bony defects. PMID:25226170

Radiological assessment of bioengineered bone in a muscle flap for the reconstruction of critical-size mandibular defect.

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Randa Al-Fotawei

Full Text Available This study presents a comprehensive radiographic evaluation of bone regeneration within a pedicled muscle flap for the reconstruction of critical size mandibular defect. The surgical defect (20 mm × 15 mm was created in the mandible of ten experimental rabbits. The masseter muscle was adapted to fill the surgical defect, a combination of calcium sulphate/hydroxyapatite cement (CERAMENT™ |SPINE SUPPORT, BMP-7 and rabbit mesenchymal stromal cells (rMSCs was injected inside the muscle tissue. Radiographic assessment was carried out on the day of surgery and at 4, 8, and 12 weeks postoperatively. At 12 weeks, the animals were sacrificed and cone beam computerized tomography (CBCT scanning and micro-computed tomography (µ-CT were carried out. Clinically, a clear layer of bone tissue was identified closely adherent to the border of the surgical defect. Sporadic radio-opaque areas within the surgical defect were detected radiographically. In comparison with the opposite non operated control side, the estimated quantitative scoring of the radio-opacity was 46.6% ± 15, the mean volume of the radio-opaque areas was 63.4% ± 20. Areas of a bone density higher than that of the mandibular bone (+35% ± 25% were detected at the borders of the surgical defect. The micro-CT analysis revealed thinner trabeculae of the regenerated bone with a more condensed trabecular pattern than the surrounding native bone. These findings suggest a rapid deposition rate of the mineralised tissue and an active remodelling process of the newly regenerated bone within the muscle flap. The novel surgical model of this study has potential clinical application; the assessment of bone regeneration using the presented radiolographic protocol is descriptive and comprehensive. The findings of this research confirm the remarkable potential of local muscle flaps as local bioreactors to induce bone formation for reconstruction of maxillofacial bony defects.

Group A T-loop for differential moment mechanics: an implant study.

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Martins, Renato Parsekian; Buschang, Peter H; Gandini, Luiz Gonzaga

2009-02-01

When anchorage control is critical and compliance is less than ideal, efficient treatment depends on differential tooth movements. The purpose of this study was to evaluate the distal tipping of partially retracted canines and the mesial movement of the molars. Eleven patients had their maxillary and mandibular canines partially retracted with TMA (Ormco Corp, Orange, Calif) T-loop springs with 45 degrees gable bends distal to the loops preactivated for group A (maximum anchorage). Metallic bone markers served as references. The canines were retracted until enough space was available for alignment of the incisors without proclination. Oblique (45 degrees) radiographs were taken immediately before the initial activation and after partial retraction. The radiographs were scanned, superimposed on the bone markers, and measured digitally. The mandibular canine crowns were retracted (4.1 +/-1.9 mm) and intruded (0.7 +/- 0.3 mm) by uncontrolled tipping. In contrast, the maxillary canine crowns were retracted (3.2 +/- 1.4 mm) by controlled tipping. The maxillary and mandibular molars crowns were protracted by similar amounts (1.0 +/- 0.6 and 1.2 +/-1.2 mm, respectively) by controlled tipping, without significant extrusion. The molars were protracted approximately 0.3 mm for every 1 mm of canine retraction. The T-loop spring used in this investigation produced controlled tipping of the maxillary canines, but it did not produce controlled tipping of the mandibular canines or translation of the molar as expected.

Extraction of Unerupted Maxillary Canine Teeth in a Maned Wolf (Chrysocyon brachyurus

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Lourdes M. B. Pessoa

2016-01-01

Full Text Available The purpose of this case report is to describe the diagnosis and treatment of unerupted canine teeth in a maned wolf. After physical examination, complete blood count, and serum biochemical profile, the animal underwent general anesthesia and head radiography was performed to confirm the diagnosis. The treatment consisted of the extraction of both maxillary canine teeth and clinical and radiographic follow-up of the right mandibular canine tooth.

Extraction of Unerupted Maxillary Canine Teeth in a Maned Wolf (Chrysocyon brachyurus)

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Pessoa, Lourdes M. B.; Roza, Marcello; Farias, Anderson; Jesus, Pedro Henrique de; Campbell, Rita de Cassia; Pinho, Mariângela Pereira de

2016-01-01

The purpose of this case report is to describe the diagnosis and treatment of unerupted canine teeth in a maned wolf. After physical examination, complete blood count, and serum biochemical profile, the animal underwent general anesthesia and head radiography was performed to confirm the diagnosis. The treatment consisted of the extraction of both maxillary canine teeth and clinical and radiographic follow-up of the right mandibular canine tooth.

Development of the canine tooth in the beagle

International Nuclear Information System (INIS)

Amimoto, A.; Iwamoto, S.; Hachimura, H.; Miyamoto, T.; Murata, T.; Taura, Y.; Nakama, S.; Hayashi, K.

1993-01-01

The growth of the crown and root in the canine tooth of beagle dogs were observed macroscopically and radiographically, and changes of occlusion with age were investigated. Completion of growth in the crown of the canine tooth was observed in both mandible and maxilla, and its eruption was accompanied by development of the dental root. The permanent canine erupted on the lingual side of deciduous canine in the mandible, and on the mesial side of the deciduous canine in the maxilla. Movement of the permanent canine to normal occlusal position(buccal direction in mandibular canine, and distal direction in maxillary canine)was followed by the loss of the deciduous canine. Coexistence of the permanent and deciduous canines occurred for about 2.4 weeks in the maxilla and about 1.4 weeks in the mandible, on average. Macroscopically, the growth of the permanent canine was completed by 33 weeks of age in the mandible and about 34 weeks of age in the maxilla. The mature root of the permanent canine was recognized radiographically at about 43 weeks of age in the mandible and 47 weeks of age in the maxilla

An alternative method in mandibular fracture treatment: bone graft use instead of a plate.

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Alagöz, Murat Sahin; Uysal, Ahmet Cagri; Sensoz, Omer

2008-03-01

In the treatment of the mandibular fractures, one of the main principles is to use the least amount of foreign material. We present an alternative technique that the bone grafts harvested from the fracture borders or from the iliac crest were used instead of plates and the fixation was done with screws. In the study including 24 mandible fractures, the bone grafts harvested from the fracture borders were used in the 10 favorable fractures and the bone grafts harvested from the iliac crest were used in the 14 unfavorable fractures. In the combined mandible fractures, four fractures were fixated with titanium plates and the other side with the bone graft. The patients, who were followed up for 12 to 20 months, were evaluated with macroscopic occlusion, panoramic graphs, and three-dimensional computerized tomographs. The advantage of this technique of fixation with the autogenous tissue is reduced infection rates and reduced operation costs. In the pediatric patients, the second session operation of plate removal is not necessary.

Mandibular osteosynthesis in a Boa constrictor snake

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Jorge Luiz Costa Castro

2014-02-01

Full Text Available Nowadays are observed an increase in the finding of certain wild animals in urban areas, due to environmental changes caused by deforestation and economic use of natural areas. It causes disappearance of usual prey and forces these animals, including snakes, to migrate to urban areas, becoming vulnerable to injuries caused by aggressions, car accidents and capture. Mandibular and maxillar fractures are common in many animal species, representing about 3-6% of all bone fractures in dogs and cats. Mandibular trauma usually occurs as a result of fights, car accidents and improper handling and/or restraint, and fractures can be closed or open, clean or contaminated. The jaw is a flat bone with differences from the long bones that should be taken into consideration for successful treatment, being minimal muscle coverage and need to maintain occlusion factors that influence the definition of the best ostheosynthesis method. The methods of stabilization include using intramedullary pins, wires, external skeletal fixation, bone plate, and acrylic resin. Conventional bone plates are efficient but related to some complications, such as the necessity of muscular elevation and high risk of injuries to mandibular structures. This article describes the successful results of the application of plate and screws in the ostheosynthesis of a mandibular fracture in a female Boa constrictor snake with weight of 8.0 kg and length of 1.80 m, at the RIOZOO Foundation (Rio de Janeiro, RJ, Brazil.

Bilateral Second Premolars Agenesia Together with a Unilateral Canine Radiculomegaly.

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Kemoli, Arthur Musakulu; Junior, Thomas Munyao

2017-01-01

Congenitally missing teeth is a common feature for the third molars. However, missing teeth, macrodontia and radiculomegaly occurring in a single patient is very rare. This article describes a case of agenesis of mandibular second premolars, radiculomegaly with dilacerations of a canine tooth together with elongated roots of other canines. All these features had been discerned through diagnostic radiographs taken during a routine treatment planning.

Surgical-prosthetic treatment of large mandibular cysts

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Džambas Ljubiša D.

2003-01-01

Full Text Available This paper presents a combined surgical-prosthetic procedure of reconstructing mandibular bone defect in a 53 year old patient, following enucleation of a mandibular cyst (Cystectomy Partsch II. After a thorough diagnostic evaluation, a surgical procedure was planned with the particular attention to the nature of the disease, patient’s condition, size and extension of the cyst, tissue loss, and the possibilities of prosthetic management of a mandibular bone defect with partial postresection dental prosthesis. It is of great importance to point to the significance of teamwork of a maxillofacial surgeon and a specialist in prosthodontics. This kind of cooperation provided very effective and less risky soft tissue, as well as bone tissue regeneration (osteogenesis. The patient’s recovery was fast, and he could return to his daily activities and work without significant changes regarding quality of life after surgery and prosthetic treatment.

Investigation of a pre-clinical mandibular bone notch defect model in miniature pigs: clinical computed tomography, micro-computed tomography, and histological evaluation.

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Carlisle, Patricia L; Guda, Teja; Silliman, David T; Lien, Wen; Hale, Robert G; Brown Baer, Pamela R

2016-02-01

To validate a critical-size mandibular bone defect model in miniature pigs. Bilateral notch defects were produced in the mandible of dentally mature miniature pigs. The right mandibular defect remained untreated while the left defect received an autograft. Bone healing was evaluated by computed tomography (CT) at 4 and 16 weeks, and by micro-CT and non-decalcified histology at 16 weeks. In both the untreated and autograft treated groups, mineralized tissue volume was reduced significantly at 4 weeks post-surgery, but was comparable to the pre-surgery levels after 16 weeks. After 16 weeks, CT analysis indicated that significantly greater bone was regenerated in the autograft treated defect than in the untreated defect (P=0.013). Regardless of the treatment, the cortical bone was superior to the defect remodeled over 16 weeks to compensate for the notch defect. The presence of considerable bone healing in both treated and untreated groups suggests that this model is inadequate as a critical-size defect. Despite healing and adaptation, the original bone geometry and quality of the pre-injured mandible was not obtained. On the other hand, this model is justified for evaluating accelerated healing and mitigating the bone remodeling response, which are both important considerations for dental implant restorations.

Effects of young-coconut juice on increasing mandibular cancellous bone in orchidectomized rats: Preliminary novel findings

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Pranee Suwanpal

2011-12-01

Full Text Available Androgens play a very important role in building the skeleton in young adults and help to prevent bone loss andosteoporosis in aging men. In addition, in hypogonadism or elderly men, bone mass has been related to estrogen levels ratherthan to testosterone. Estrogen replacement therapy has therefore been proposed to prevent bone loss in males as well as infemales. Estrogen, however, has been considered to be one of the hormonal risk factors for benign prostatic hyperplasia andprostate cancer and also has other side effects. Young coconut juice (YCJ presumably containing phytoestrogen was investigatedin the present study for its possible beneficial effects on delaying osteoporosis using a male rat model, and by this totest the possibility that it might be able to replace estrogen replacement therapy without side effects. In this study, mandibularcancellous bone was used as the osteoporotic model. Using the same model, we have previously found that total cartilagethickness particularly the hypertrophic zone of mandibular condylar cartilage was thicker in the sham-operated rats receivingYCJ orally fed for a 14 day period, compared with sham, orchidectomized animal, orchidectomized rats receiving estradiolbenzoate, and orchidectomized rats receiving YCJ. The present study confirmed our former study that mandibular cancellousbone in the sham-operated rats and in the orchidectomized rats receiving YCJ orally fed for a 14–day period were thicker thanthose of the sham and orchidectomized rat groups. This study results are novel and they indicate that YCJ may have beneficialeffects in the treatment of osteoporosis in andropause men.

[Temporo-mandibular joint. Morpho-functional considerations].

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Scutariu, M D; Indrei, Anca

2004-01-01

The temporo-mandibular joint is distinguished from most other synovial joints of the body by two features: 1. the two jointed components carry teeth whose position and occlusion introduce a very strong influence on the movements of the temporo-mandibular joint and 2. its articular surfaces are not covered by hyaline cartilage, but by a dense, fibrous tissue. This paper describes the parts of the temporo-mandibular joint: the articular surfaces (the condylar process of the mandible and the glenoid part of the temporal bone), the fibrocartilaginous disc which is interposed between the mandibular and the temporal surface, the fibrous capsule of the temporo-mandibular joint and the ligaments of this joint. All these parts present a very strong adaptation at the important functions of the temporo-mandibular joint.

Bilateral second premolars agenesia together with a unilateral canine radiculomegaly

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Arthur Musakulu Kemoli

2017-01-01

Full Text Available Congenitally missing teeth is a common feature for the third molars. However, missing teeth, macrodontia and radiculomegaly occurring in a single patient is very rare. This article describes a case of agenesis of mandibular second premolars, radiculomegaly with dilacerations of a canine tooth together with elongated roots of other canines. All these features had been discerned through diagnostic radiographs taken during a routine treatment planning.

Is 3D-CT reformation using free software applicable to diagnosis of bone changes in mandibular condyles?

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Marília Gerhardt de Oliveira

2009-06-01

Full Text Available OBJECTIVES: This study evaluated the agreement of computed tomography (CT imaging using 3D reformations (3DR with shaded surface display (SSD and maximum intensity projection (MIP in the diagnosis of bone changes in mandibular condyles of patients with rheumatoid arthritis (RA, and compared findings with multiplanar reformation (MPR images, used as the criterion standard. MATERIAL AND METHODS: Axial CT images of 44 temporomandibular joints (TMJs of 22 patients with RA were used. Images were recorded in DICOM format and assessed using free software (ImageJ. Each sample had its 3DR-SSD and 3DR-MIP results compared in pairs with the MPR results. RESULTS: Slight agreement (k = 0.0374 was found in almost all comparisons. The level of agreement showed that 3DR-SSD and 3DR-MIP yielded a number of false-negative results that was statistically significant when compared with MPR. CONCLUSIONS: 3DR-SSD or 3DR-MIP should only be used as adjuvant techniques to MPR in the diagnosis of bone changes in mandibular condyles.

Canine index – A tool for sex determination

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Shankar M. Bakkannavar

2015-12-01

Full Text Available Teeth are most useful tools in victim identification in the living as well as the dead in the field of forensic investigations. Their ability to survive in situations like mass disasters makes them constructive devices. Many authors have measured crowns of teeth in both males and females and found certain variations. Canines, reported to survive in air crash and hurricane disasters, are perhaps the most stable teeth in the oral cavity because of the labiolingual thickness of the crown and the root anchorage in the alveolar process of jaws. Measurement of mesiodistal width of the mandibular canines and inter-canine distance of the mandible provides good evidence of sex identification due to dimorphism. This study was undertaken to evaluate the effectiveness of canine index (CI in the determination of sex.

Dental magnetic resonance tomography (dental-MRT) as a method for imaging of the maxillo-mandibular bone

International Nuclear Information System (INIS)

Gahleitner, A.; Nasel, C.; Schick, S.; Dorffner, S.; Imhof, H.; Trattnig, S.; Bernhart, T.; Mailath, G.; Watzek, G.

1998-01-01

Purpose: To establish a new method for dental imaging using magnetic resonance tomography named Dental-MRT and to demonstrate its usefulness in diagnosing dentogen pathologies of the mandible and maxilla. Methods: Seven healthy volunteers, three patients with pulpitis, two patients with dentigerous cysts, two patients after tooth transplantation, and three patients with atrophic mandibles have been evaluated. Optimized axial T 1 - and T 2 -weighted gradient echo and spin echo sequences in 2D and 3D technique have been established to perform studies of the jaws. The acquired images were reconstructed with a standard dental software package on a workstation as panorama and cross-sectional views of the mandible or maxilla. Results: The entire maxillo-mandibular bone, teeth, dental pulp, and the content of the mandibular canal were well depicted. Patients with pulpitis demonstrate bone marrow edema in the periapical region. Dentigerous cysts and their relation to the surrounding structures are clearly shown. After contrast media administration marked enhancement of the dental pulp can be demonstrated. Conclusion: Dental-MRT promises to provide a new tool for visualization and detection of dental diseases. (orig.) [de

[Exploring a new method for superimposition of pre-treatment and post-treatment mandibular digital dental casts in adults].

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Dai, F F; Liu, Y; Xu, T M; Chen, G

2018-04-18

To explore a cone beam computed tomography (CBCT)-independent method for mandibular digital dental cast superimposition to evaluate three-dimensional (3D) mandibular tooth movement after orthodontic treatment in adults, and to evaluate the accuracy of this method. Fifteen post-extraction orthodontic treatment adults from the Department of Orthodontics, Peking University School and Hospital of Stomatology were included. All the patients had four first premolars extracted, and were treated with straight wire appliance. The pre- and post-treatment plaster dental casts and craniofacial CBCT scans were obtained. The plaster dental casts were transferred to digital dental casts by 3D laser scanning, and lateral cephalograms were created from the craniofacial CBCT scans by orthogonal projection. The lateral cephalogram-based mandibular digital dental cast superimposition was achieved by sequential maxillary dental cast superimposition registered on the palatal stable region, occlusal transfer, and adjustment of mandibular rotation and translation obtained from lateral cephalogram superimposition. The accuracy of the lateral cephalogram-based mandibular digital dental cast superimposition method was evaluated with the CBCT-based mandibular digital dental cast superimposition method as the standard reference. After mandibular digital dental cast superimposition using both methods, 3D coordinate system was established, and 3D displacements of the lower bilateral first molars, canines and central incisors were measured. Differences between the two superimposition methods in tooth displacement measurements were assessed using the paired t-test with the level of statistical significance set at Pdigital dental cast superimposition methods in 3D displacements of the lower first molars, and sagittal and vertical displacements of the canines and central incisors; transverse displacements of the canines and central incisors differed by (0.3±0.5) mm with statistical significance

An in vivo evaluation of PLLA/PLLA-gHA nano-composite for internal fixation of mandibular bone fractures.

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Peng, Weihai; Zheng, Wei; Shi, Kai; Wang, Wangshu; Shao, Ying; Zhang, Duo

2015-11-09

Internal fixation of bone fractures using biodegradable poly(L-lactic-acid) (PLLA)-based materials has attracted the attention of many researchers. In the present study, 36 male beagle dogs were randomly assigned to two groups: PLLA/PLLA-gHA (PLLA-grafted hydroxyapatite) group and PLLA group. PLLA/PLLA-gHA and PLLA plates were embedded in the muscular bags of the erector spinae and also implanted to fix mandibular bone fractures in respective groups. At 1, 2, 3, 6, 9, and 12 months postoperatively, the PLLA/PLLA-gHA and PLLA plates were evaluated by adsorption and degradation tests, and the mandibles were examined through radiographic analysis, biomechanical testing, and histological analysis. The PLLA/PLLA-gHA plates were non-transparent and showed a creamy white color, and the PLLA plates were transparent and faint yellow in color. At all time points following surgery, adsorption and degradation of the PLLA/PLLA-gHA plates were significantly less than those of the PLLA plates, and the lateral and longitudinal bending strengths of the surgically treated mandibles of the beagle dogs in the PLLA/PLLA-gHA group were significantly greater than those of the PLLA group and reached almost the value of intact mandibles at 12 months postoperatively. Additionally, relatively rapid bone healing was observed in the PLLA/PLLA-gHA group with the formation of new lamellar bone tissues at 12 months after the surgery. The PLLA/PLLA-gHA nano-composite can be employed as a biodegradable material for internal fixation of mandibular bone fractures.

An in vivo evaluation of PLLA/PLLA-gHA nano-composite for internal fixation of mandibular bone fractures

International Nuclear Information System (INIS)

Peng, Weihai; Shi, Kai; Wang, Wangshu; Shao, Ying; Zhang, Duo; Zheng, Wei

2015-01-01

Internal fixation of bone fractures using biodegradable poly(L-lactic-acid) (PLLA)-based materials has attracted the attention of many researchers. In the present study, 36 male beagle dogs were randomly assigned to two groups: PLLA/PLLA-gHA (PLLA-grafted hydroxyapatite) group and PLLA group. PLLA/PLLA-gHA and PLLA plates were embedded in the muscular bags of the erector spinae and also implanted to fix mandibular bone fractures in respective groups. At 1, 2, 3, 6, 9, and 12 months postoperatively, the PLLA/PLLA-gHA and PLLA plates were evaluated by adsorption and degradation tests, and the mandibles were examined through radiographic analysis, biomechanical testing, and histological analysis. The PLLA/PLLA-gHA plates were non-transparent and showed a creamy white color, and the PLLA plates were transparent and faint yellow in color. At all time points following surgery, adsorption and degradation of the PLLA/PLLA-gHA plates were significantly less than those of the PLLA plates, and the lateral and longitudinal bending strengths of the surgically treated mandibles of the beagle dogs in the PLLA/PLLA-gHA group were significantly greater than those of the PLLA group and reached almost the value of intact mandibles at 12 months postoperatively. Additionally, relatively rapid bone healing was observed in the PLLA/PLLA-gHA group with the formation of new lamellar bone tissues at 12 months after the surgery. The PLLA/PLLA-gHA nano-composite can be employed as a biodegradable material for internal fixation of mandibular bone fractures. (paper)

Efficacy of platelet rich plasma and hydroxyapatite crystals in bone regeneration after surgical removal of mandibular third molars.

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Kaur, Preeti; Maria, Anisha

2013-03-01

This study evaluates the efficacy of platelet rich plasma (PRP) & porous hydroxyapatite crystals in bone regeneration after surgical removal of mandibular third molar with the help of radiographs and its comparison with control side. A total of 40 patients; both male and female aged between 18 and 35 years, who had impacted mandibular third molars were randomly selected for this study. Twenty patients were taken for control group and 20 patients for study group. The extraction socket of the study group was packed with PRP and hydroxyapatite granules and that of control group was sutured without PRP and hydroxyapatite. The bone density of both extraction sockets were evaluated radiographically using gray level histogram and compared periodically on immediate postoperative day, 1st and 3rd month postoperatively and postoperative sequelae of both the control group and study group in terms of oedema & pain or any other adverse reactions were also assessed. Data suggested evidence of early bone formation and maturation radiographically in study group as compared to control group. The percentage of facial swelling was numerically greater on the control side as compared to the study side, Pain was also assessed with VAS and it was found that the severity of pain was equal in both study and control groups and the results were not significant. This study clearly indicated a definitive improvement in the wound healing, increase in bone density, which signifies and highlights the use of PRP and hydroxyapatite granules, certainly as a valid method in inducing and accelerating bone regeneration.

Transient recycling of resected bone to facilitate mandibular reconstruction--a technical note.

Science.gov (United States)

Lee, Jing-Wei; Tsai, Shin-Sheng; Kuo, Yao-Lung

2006-10-01

Mandibular reconstruction requires considerable sculptural skills. The intriguingly complex configuration of the structure is difficult to reproduce. It is thus imperative for surgeons to seek a technique that improves the precision of the reconstruction. A 55-year-old male presented with a full thickness cancer (T4+) of his left cheek. Radical ablative surgery resulted in an extensive loss of bone and soft tissue mandating major reconstruction. The resected bony specimen was thoroughly denuded, autoclaved, and then placed back into its original site so that the mandible resumed its pre-surgical configuration. A reconstruction plate was applied to maintain structural stability, then the "recycled bone" was used as a template and replaced with a free fibular graft. The patient fared well and a follow-up panoramic radiograph demonstrated good alignment and symmetry of the reconstructed mandible. This method is a viable option for segmental mandibulectomy defect repair in selected cases. Using this technique, it is possible to restore the original bony contour expediently and accurately.

Evaluation of the bone microstructures after the mandibular reconstruction, using bioresorbable hydroxyapatite/poly-L-lactide mesh tray and the particulate cancellous bone

International Nuclear Information System (INIS)

Takahashi, Hidetoshi; Matsuo, Akira; Chiba, Hiroshige

2010-01-01

The combination of particulate cancellous bone and marrow (PCBM) and a titanium tray is frequently used for mandibular reconstruction. However, there are difficulties in bending the tray and forming a suitable contour. In addition, the metallic ions elute into the living body and the hinders the implant insertion; therefore, a removable operation is required after reconstruction. Hydroxyapatite/poly-L-lactide (HA/PLLA) is a bone-bonding material that has both bio-activity and bio-resorbability. It may overcome the weakness of a titanium tray, but the bone microstructures have not been evaluated after the use of this tray for PCBM reconstruction. We created defects on the mandible of a beagle and reconstructed it by filling it with a mixture of PCBM and PRP using the HA/PLLA tray. We examined the bone-formation mechanism using a confocal laser microscope and bone microstructural analysis using microCT. As a result, compared to the titanium tray, the bone-formation is delayed during the first 3 to 6 months with an HA/PLLA tray. However, a formation of new bone with equal quality is observed after 12 months. According to the bone microstructural measurement, both of them had higher bone volume fraction than the native bone but other parameters were the same. From the above, the quantity of the new bone in the HA/PLLA tray is the same as the bone in the titanium tray, and has equal bone microstructures with the surrounding native bone. (author)

Regenerative approach to bilateral rostral mandibular reconstruction in a case series of dogs

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Boaz eArzi

2015-03-01

Full Text Available Extensive rostral mandibulectomy in dogs typically results in instability of the mandibles that may lead to malocclusion, difficulty in eating and drinking, food prehension, and pain of the temporomandibular joint. Large rostral mandibular defects are challenging to reconstruct due to the complex geometry of this region. In order to restore mandibular continuity and stability following extensive rostral mandibulectomy, we developed a surgical technique using a combination of intraoral and extraoral approaches, a locking titanium plate and a compression resistant matrix (CRM infused with rhBMP-2. Furthermore, surgical planning that consisted of computed tomographic (CT scanning and 3D model printing were utilized. We describe a regenerative surgical technique for immediate or delayed reconstruction of critical-size rostral mandibular defects in 5 dogs. Three dogs had healed with intact gingival covering over the mandibular defect and had immediate return to normal function and occlusion. Two dogs had the complication of focal plate exposure and dehiscence, which was corrected with mucosal flaps and suturing; these dogs have since healed with intact gingival covering over the mandibular defect. Mineralized tissue formation was palpated clinically within 2 weeks and solid bone formation within 3 months. Computed tomography findings at 6 months postoperatively demonstrated that the newly regenerated mandibular bone had increased in mineral volume with evidence of integration between the native bone, new bone and CRM compared to the immediate postoperative CT. We conclude that rostral mandibular reconstruction using a regenerative approach provides an excellent solution for restoring mandibular continuity and preventing mandibular instability in dogs.

Developmental and radiobiologic characteristics of canine multinucleated, osteoclast-like cells generated in vitro from canine bone marrow

International Nuclear Information System (INIS)

Seed, T.M.; Kaspar, L.V.; Domann, F.; Niiro, G.K.; LeBuis, D.A.

1988-01-01

We report here our initial observations on the growth and morphology, and developmental radiosensitivity of giant, multinucleated, osteoclast-like cells (MN-OS) generated through in vitro cultivation of hematopoietic progenitor-enriched canine bone marrow samples. Maximum cell densities of 5.5 x 10(3) to 6.5 x 10(3) MN-OS per cm2 of growth area were achieved following 10 to 14 days of culture at 37 degrees C. Acute gamma irradiation of the initial marrow inocula resulted in significant, dose-dependent perturbations of MN-OS formation, growth, and development. Attempts to estimate radiosensitivity of MN-OS progenitors from canine marrow yielded a range of Do values from a low of 212 cGy measured at six days of culture to higher values of 405 to 542 cGy following 10 to 22 days of culture. At the intermediate times of culture (10 to 14 days), the radiation-induced responses were clearly biphasic, reflecting either (a) the presence of multiple subpopulations of MN-OS progenitors with varying degrees of radiosensitivity or (b) the inherent biphasic nature of MN-OS development involving early progenitor cell proliferation followed by maturation and subsequent fusion. Morphologically, MN-OS generated from irradiated marrow inocula appeared only marginally altered, with alterations expressed largely in a biphasic, dose-dependent fashion in terms of smaller cell size, reduced number of nuclei, increased expression of both surface microprojections, and a unique set of crystalloid cytoplasmic inclusions. Functionally, MN-OS appeared to be impaired by irradiation of marrow progenitors, as evidenced by failure to initiate resorptive attachments to devitalized bone spicules in vitro

The effects of orthognathic surgery on mandibular movements in patients with mandibular prognathism

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Sinobad Vladimir

2012-01-01

Full Text Available Introduction. Mandibular prognathism, one of the most severe dentofacial deformities, affects the person’s appearance, psychological health and the quality of life in the most sensitive age period. Objective. The aim of this study was to evaluate the effects of sagittal split ramus osteotomy on the range of mandibular border movements in the early postoperative period. Methods. The study was conducted on 20 patients, of mean age 20.8 years, with mandibular prognathism. All patients included in this study were operated on by bilateral sagittal spliting ramus osteotomy according to Obwegeser and Dal Pont followed by mandibular immobilization during eight weeks. In all patients mandibular border movements were recorded before and six months after surgery using the computerized pantograph Arcus-Digma (KaVo EWL GmbH, Leutkirch, Germany. Results. The analysis of the chosen kinematic parameters revealed that sagittal split ramus osteotomy followed by eight weeks of mandibular immobilization had severe effects on the mouth opening. Six months after surgery the range of maximal mouth opening decreased for approximately 13.9 mm in relation to the preoperative stage. On the contrary, the ranges of maximal protrusion and the border of laterotrusive excursions increased significantly after surgery. Conclusion. In patients with mandibular prognathism where enormous mandibular growth was the main causal factor of the deformity, the sagittal split ramus osteotomy yielded good results. The rigid fixation of bone fragments and reduced period of mandibular immobilization followed by appropriate physical therapy could considerably contribute to a more rapid recovery of mandibular kinematics in the postoperative period.

Filling of extraction sockets with autogenous bone in cats Preenchimento de alvéolos dentais de gatos com osso autógeno

Directory of Open Access Journals (Sweden)

Adelina Maria da Silva

2012-01-01

Full Text Available PURPOSE: To evaluate bone healing in the extraction socket of the feline mandibular canine tooth after grafting. METHODS: Eighteen adult cats were submitted to unilateral extraction of mandibular canine tooth and divided into three groups. In group 1 (n=6, control, the extraction socket was left empty. In group 2 (n=6, the extraction socket was filled with autogenous cancelous bone from the iliac crest and in group 3 (n=6, with cortical bone chips from the iliac crest. Cats were euthanized at 6 weeks postoperative. RESULTS: Immediate postoperative radiographs in dorsoventral view showed a radiolucent area at the extraction wound. A decreased radiolucency was observed on the radiographs taken at 6 weeks postoperative. Histological examination showed formation of woven bone within the extraction socket. The percentage of newly formed bone within the extraction socket, measured by the histometry, showed no statistically significant difference among the values of the three groups (Kruskal-Wallis'test p>0.05 (group 1: 52.54 ± 15.46, group 2: 50.51 ± 5.01, group 3: 51.85 ± 9.52. CONCLUSION: The bone regeneration observed in the extraction sockets filled with autogenous cancellous bone or autogenous cortical bone chips was similar to that observed in the control sites, given an observation period of 6 weeks after extraction of the mandibular canine tooth.OBJETIVO: Avaliar a regeneração óssea de alvéolos dentais de gatos após enxertia. MÉTODOS: Dezoito gatos adultos, distribuídos em três grupos de 6 animais cada, foram submetidos a extração do canino mandibular direito ou esquerdo. No grupo 1, controle, o alvéolo foi deixado vazio. No grupo 2, o alvéolo foi preenchido com osso esponjoso autógeno do osso ilíaco e no grupo 3, com raspa de osso cortical do osso ilíaco. Os animais foram submetidos à eutanásia 6 semanas após a cirurgia. RESULTADOS: Nas radiografias realizadas no pós-operatório imediato na projeção ventrodorsal

The impact on bone tissues of immediate implant-supported mandibular overdentures with cusped and cuspless teeth

OpenAIRE

Khalid A. Arafa

2016-01-01

Objectives: To examine the effects on bone tissues of immediate implant-supported mandibular overdentures with cusped or cuspless teeth. Methods: A randomized controlled trial was conducted at the Dental Clinic, Faculty of Dentistry, Al-Azhar University, Assiut Branch, Egypt, over a 12-month period from September 2013 to September 2014. Twenty patients were treated with immediate implant-supported overdentures: one group received overdentures with cusped teeth, and the other group receive...

A new method for rapid Canine retraction

Directory of Open Access Journals (Sweden)

"Khavari A

2001-06-01

Full Text Available Distraction osteogenesis method (Do in bone lengthening and rapid midpalatal expansion have shown the great ability of osteognic tissues for rapid bone formation under distraction force and special protocol with optimum rate of one millimeter per day. Periodontal membrane of teeth (PDM is the extension of periostium in the alveolar socked. Orthodontic force distracts PDM fibers in the tension side and then bone formation will begin.Objects: Rapid retraction of canine tooth into extraction space of first premolar by DO protocol in order to show the ability of the PDM in rapid bone formation. The other objective was reducing total orthodontic treatment time of extraction cases.Patients and Methods: Tweleve maxillary canines in six patients were retracted rapidly in three weeks by a custom-made tooth-born appliance. Radiographic records were taken to evaluate the effects of heavy applied force on canine and anchorage teeth.Results: Average retraction was 7.05 mm in three weeks (2.35 mm/week. Canines rotated distal- in by mean 3.5 degrees.Anchorage loss was from 0 to 0.8 mm with average of 0.3 mm.Root resorption of canines was negligible, and was not significant clinically. Periodontium was normal after rapid retraction. No hazard for pulp vitality was observed.Discussion: PDM responded well to heavy distraction force by Do protocol. Rapid canine retraction seems to be a safe method and can considerabely reduce orthodontic time.

Peripheral Osteoma of the Mandibular Notch: Report of a Case

International Nuclear Information System (INIS)

Iwai, Toshinori; Izumi, Toshiharu; Baba, Junichi; Maegawa, Jiro; Mitsudo, Kenji; Tohnai, Iwai

2013-01-01

Osteoma is a benign, slow-growing osteogenic tumor that sometimes arises from the craniomaxillofacial region, such as the sinus, temporal or jaw bones. Osteoma consists of compact or cancellous bone that may be peripheral, central or extraskeletal type. Peripheral osteoma arises from the periosteum and is commonly a unilateral, pedunculated mushroom-like mass. Peripheral osteoma of the mandible is relatively uncommon, and peripheral osteoma of the mandibular notch is extremely rare, although many cases arise from the mandibular body, angle, condyle, or coronoid process. We report here an unusual peripheral osteoma of the mandibular notch in a 78-year-old nonsyndromic female

99mTc-methoxy-isobutyl-isonitrile (sestamibi) imaging of malignant canine lymphoma

International Nuclear Information System (INIS)

Steyn, P.F.; Ogilvie, G.

1995-01-01

Technetium-99m methoxy-isobutyl-isonitrile (sestamibi) imaging of malignant canine lymphoma was performed in thirteen dogs 1 hour after intravenous injection of 99mTc-sestamibi at 13 MBq (0.35 mCi) per kilogram body weight. Abnormal tracer uptake was visualized in the liver, spleen, bone marrow, and mesenteric, inguinal, popliteal, sternal, cranial cervical and mandibular lymph nodes. Radiopharmaceutical uptake was also noted in a nasal mass. One large neoplastic renal mass did not have demonstrable sestamibi uptake. Other regions had no significant difference in the target:background ratios when compared with values from normal dogs (P > 0.05). 99mTc-sestamibi can be used to image malignant lymphoma, and has potential applications in the management of patients to document response to treatment and to stage of extent of disease

Dynamic MR imaging of mandibular osteoradionecrosis

International Nuclear Information System (INIS)

Store, G.; Smith, H.J.; Larheim, T.A.

2000-01-01

Osteoradionecrotic bone has been characterised as hypovascular and metabolically inactive tissue with impaired perfusion. The present study was conducted to determine if dynamic contrast-enhanced MR imaging could provide additional information about the vascularity of radionecrotic mandibular bone. Dynamic contrast-enhanced MR imaging was performed on 10 patients with mandibular osteoradionecrosis (ORN), and on 6 patients, irradiated for oropharyngeal tumours, without symptoms or signs of ORN. Nine patients in the ORN group received a series of 20 hyperbaric oxygen (HBO) treatments, after which the dynamic MR investigation was repeated. Radiation per se did not lead to increased contrast enhancement, whereas all patients with ORN showed marked contrast enhancement of the osteoradionecrotic bone marrow. After HBO treatment, pathological contrast enhancement of the abnormal bone marrow could still be seen, but the rate of enhancement was less than before in 7 of 9 patients. Two patients had an increase in the enhancement rate. The findings suggest the existence of an increased and patent microvasculature

Changes in the edentulous maxilla with ball and telescopic attachments of implant-retained mandibular overdentures: a 4-year retrospective study.

Science.gov (United States)

Elsyad, Moustafa Abdou; Khairallah, Ahmed Samir; Shawky, Ahmad Fathalla

2013-07-01

This retrospective study investigated the clinical and radiographic changes in the edentulous maxilla in patients with either ball or telescopic attachments of implantretained mandibular overdentures. Thirty-two completely edentulous patients (21 males and 11 females) received two implants in the canine region of the mandible. New maxillary complete dentures and mandibular overdentures were fabricated. Overdentures were connected to the implants either with ball (group 1, n = 16) or telescopic (group 2, n = 16) attachments. Retention and stability of the maxillary denture as well as mucosal changes of the maxillary ridge were recorded after 4 years of denturewearing. Traced rotational tomograms were used for measurements of maxillary alveolar bone loss. The proportional value between bone areas and areas of reference not subject to resorption was expressed as a ratio (R). Change in R immediately before (T0) and after 4 years (T4) of overdenture insertion was calculated for the anterior and posterior regions of the maxilla. After 4 years of denture-wearing, maxillary denture retention was significantly higher in group 1 than in group 2, while occurrence of flabby ridges was significantly higher in group 2 than in group 1. The change in R of the anterior region of the maxilla was significantly higher than the change in the posterior region in both groups. Group 2 showed significant anterior residual ridge resorption compared to group 1. Telescopic attachments for implant-retained mandibular overdentures are associated with increased maxillary ridge resorption and flabbiness, and decreased maxillary denture retention when compared to ball attachments.

Finite element analysis of dental implant loading on atrophic and non-atrophic cancellous and cortical mandibular bone - a feasibility study

NARCIS (Netherlands)

Marcián, P.; Borák, L.; Valášek, J.; Kaiser, J.; Florian, Z.; Wolff, J.

2014-01-01

The first aim of this study was to assess displacements and micro-strain induced on different grades of atrophic cortical and trabecular mandibular bone by axially loaded dental implants using finite element analysis (FEA). The second aim was to assess the micro-strain induced by different implant

The effects of canine bone marrow stromal cells on neuritogenesis from dorsal root ganglion neurons in vitro.

Science.gov (United States)

Kamishina, Hiroaki; Cheeseman, Jennifer A; Clemmons, Roger M

2009-10-01

The present in vitro study was designed to evaluate whether canine bone marrow stromal cells (BMSCs) promote neurite outgrowth from dorsal root ganglion (DRG) neurons. Bone marrow aspirates were collected from iliac crests of three young adult dogs. DRG neurons were cultured on BMSCs, fibroblasts, or laminin substrates. DRG neurons were also cultured in BMSC- or fibroblast-conditioned media. DRG neurons grown on BMSCs extended longer neurites and developed a much more elaborate conformation of branching neurites compared to those on fibroblasts or laminin. Quantitative analysis revealed that these effects were associated with the emergence of increased numbers of primary and branching neurites. The effect appears to be dependent upon cell-cell interactions rather than by elaboration of diffusible molecules. With more extensive investigations into the basic biology of canine BMSCs, their ability for promoting neurite outgrowth may be translated into a novel therapeutic strategy for dogs with a variety of neurological disorders.

Expansion of Mandibular Knife-Edge Ridge and Simultaneous Implant Placement to Retain Overdentures: One-Year Clinical and Radiographic Results of a Prospective Study.

Science.gov (United States)

ELsyad, Moustafa Abdou; Hammouda, Nelly Ibrahim

2017-02-01

The aim of this study was to evaluate and compare the clinical and radiographic outcomes of two implants placed in expanded mandibular knife-edge ridge and implants placed in unexpanded ridges to retain overdentures. Fifteen completely edentulous patients with knife-edge ridges at canine areas of the mandible received two implants using the ridge expansion technique (study group, SG). Expansion was performed using piezoelectric corticotomy, and self-threading expanders. The control group (CG) comprised patients who received two-implant at canine areas without ridge expansion but were all case matched to SG and served as historical cohort. In both groups, mandibular overdentures were connected to the implants with Locator attachments 3 months after implant placement. Clinical (Plaque index; PI, Gingival index; GI, Probing depth; PD, and implant stability; ISQ) and radiographic (Vertical bone loss; VBL) parameters were recorded at time of overdenture insertion (base line, T0), 6 months (T6), and 12 months (T12) after insertion. The cumulative success rates were 100% and 96.4% for CG and SG, respectively, without significant difference between groups. All tested parameters increased significantly with advance of time in both groups. There was no significant difference in PI, GI, PD, and ISQ between groups. However, SG recorded significant higher VBL than CG at T6 and T12. Expansion of mandibular knife edge ridge and simultaneous placement of implants to retain overdentures is associated with clinic and radiographic outcomes comparable to implants placed in unexpanded ridges after 1 year. However, long term randomized controlled trials with sufficient sample size are still needed to ensure the findings of the present study. © 2016 Wiley Periodicals, Inc.

Implant angulation: 2-year retrospective analysis on the influence of dental implant angle insertion on marginal bone resorption in maxillary and mandibular osseous onlay grafts.

Science.gov (United States)

Ramaglia, Luca; Toti, Paolo; Sbordone, Carolina; Guidetti, Franco; Martuscelli, Ranieri; Sbordone, Ludovico

2015-05-01

The purpose of this study was to determine the existence of correlations between marginal peri-implant linear bone loss and the angulation of implants in maxillary and mandibular augmented areas over the course of a 2-year survey. Dependent variables described the sample of the present retrospective chart review. By using three-dimensional radiographs, input variables, describing the implant angulation (buccal-lingual angle [φ] and mesial-distal angle [θ]) were measured; outcome variables described survival rate and marginal bone resorption (MBR) around dental implants in autogenous grafts (10 maxillae and 14 mandibles). Pairwise comparisons and linear correlation coefficient were computed. The peri-implant MBR in maxillary buccal and palatal areas appeared less intensive in the presence of an increased angulation of an implant towards the palatal side. Minor MBR was recorded around mandibular dental implants positioned at a right angle and slightly angulated towards the mesial. Resorption in buccal areas may be less intensive as the angulation of placed implants increases towards the palatal area in the maxilla, whereas for the mandible, a greater inclination towards the lingual area could be negative. In the mandibular group, when the implant was slightly angulated in the direction of the distal area, bone resorption seemed to be more marked in the buccal area. In the planning of dental implant placement in reconstructed alveolar bone with autograft, the extremely unfavourable resorption at the buccal aspect should be considered; this marginal bone loss seemed to be very sensitive to the angulation of the dental implant.

Does the titanium plate fixation of symphyseal fracture affect mandibular growth?

Science.gov (United States)

Bayram, Burak; Yilmaz, Alev Cetinsahin; Ersoz, Esra; Uckan, Sina

2012-11-01

The effect of metallic fixation on growth is a major concern in children and is not yet clear. The aim of this study was to evaluate the effect of metallic fixation of mandibular symphyseal fracture on mandibular growth.Eighteen 90-day-old growing white New Zealand rabbits weighing 1.6 to 2.5 kg were included in this study and divided into 2 groups of 9 subjects. In the experimental group, animals underwent mandibular osteotomy, simulating a symphyseal fracture on the midline of mandibular symphysis. The bone segments were fixed with microplates and microscrews (1.6 mm).In the control group, the same surgical incision without performing symphyseal osteotomy was conducted, and 2 screws were inserted on each side of the symphyseal midline.Digital cephalometric and submentovertex radiographs were taken before the operation and at postoperative 6 months for each animal in 2 groups, and cephalometric measurements were performed. The distance between the centers of the head of 2 screws measured at the end of surgery in the control group was compared with measurements at 6 months after surgery. Obtained data were statistically analyzed.There is no statistically significant difference between the 2 groups for growth amount of both sides of the mandible. Difference of ANS-Id (the most anterior points of nasal bone, the most anterior point on the alveolar bone between the lower incisors) and Cd-Id (the uppermost and most distal point of the mandibular condyle, the most anterior point on the alveolar bone between the lower incisors) values of the 2 groups is not statistically significant (P > 0.05).The distance between the 2 screws at the first application significantly increased at the postoperative sixth month (P mandibular symphyseal fracture does not affect the vertical and sagittal mandibular growth in growing rabbits.

In vitro studies on the radiosensitivity of multipotent hemopoietic progenitors in canine bone marrow

International Nuclear Information System (INIS)

Kreja, L.; Weinsheimer, W.; Nothdurft, W.

1991-01-01

The in vitro radiation response to 280-kV x-rays (does rate 72 cGy/min) of multipotent hemopoietic progenitor cells, mixed colony-forming units (CFU-mix), from canine bone marrow was assayed and compared to the radiation response characteristics of early erythroid progenitors, erythroid burst-forming units (BFU-E). To improve the colony-forming efficiency, the effect of various bone marrow cell separation techniques on colony formation of both progenitors was examined. The separation of bone marrow aspirates by discontinuous buoyant gradient centrifugation using the lymphocyte separation medium Lymphoprep with a density of 1.070 g/ml allowed the establishment of reproducible survival curves. The survival curves for both progenitors were strictly exponential, and CFU-mix were found to be more radiosensitive (D0 = 12 ± 2 cGy) than BFU-E (D0 = 16 ± 2 cGy)

The Effect of Using a Modified Dentoalveolar Distractor on Canine Angulation following Rapid Canine Retraction: A Split-mouth Design Randomized Controlled Trial.

Science.gov (United States)

Al-Ainawi, Khaled I; Al-Mdalal, Yaser; Hajeer, Mohammad Y

2016-01-01

New studies have been published and aimed to retract canines by means of distraction osteogenesis to reduce treatment time. Although a great care has been given to achieve a bodily movement of the canines, a significant amount of tipping of the canines has been observed. This trial aimed to assess the effect of applying a modified distractor on canine angulation. The sample of the study consisted of 14 canines in seven patients (16-25 years). After the osteotomy procedure, two distractors were applied (one distractor on each side). After 5 days of a latency period, the two distractors were activated at a rate of 1 mm/day. There was a significant difference between the two distractors regarding the time required to retract the canines (p = 0.008) and the observed change in canine angulation following retraction (p = 0.028). The change in the overjet and the mandibular plane angle was statistically insignificant. Eight out of 14 distracted canines reacted positively to the pulp vitality tester after 3 months of completion of distraction. There was no clinical sign of discoloration or pulpal pain in any canine. Within the limits of this study, the modified distractor caused a bodily movement of the canine with a minimal tipping. Further research is required on a long-term basis on a larger group of patients to gain more insight on the observed changes.

Traumatic bone cyst, idiopathic origin

African Journals Online (AJOL)

GB

2014-04-02

Apr 2, 2014 ... CONCLUSION: The majority of TBCs are located in the mandibular body between the canine and the third molar. ... altered calcium metabolism, low-grade infection, .... asymptomatic nature of the disease is the reason.

Finite element analysis of dental implant loading on atrophic and non-atrophic cancellous and cortical mandibular bone – a feasibility study

NARCIS (Netherlands)

Marcian, P.; Borak, L.; Valasek, J.; Kaiser, J.; Florian, Z.; Wolff, J.E.H.

2014-01-01

The first aim of this study was to assess displacements and micro-strain induced on different grades of atrophic cortical and trabecular mandibular bone by axially loaded dental implants using finite element analysis (FEA). The second aim was to assess the micro-strain induced by different implant

Digital radiographic evaluation of alveolar bone loss, density and lamina dura integrity on post splinting mandibular anterior with chronic periodontitis

Science.gov (United States)

Rafini, F.; Priaminiarti, M.; Sukardi, I.; Lessang, R.

2017-08-01

The healing of periodontal splinting can be detected both with clinical and radiographic examination. In this study, the alveolar bone was evaluated by radiographic digital periapical analysis. Periodontal tooth splinting is periodontal support therapy used to prevent periodontal injury during repair and regeneration of periodontal therapy. Radiographic digital periapical analysis of alveolar bone in the mandibular anterior region with chronic periodontitis and 2/3 cervical bone loss after three months of periodontal splinting. Eighty four proximal site (43 mesial and 41 distal) from 16 patients with chronic periodontitis and treated with spinting were examined by taking periapical digital radiographic at day 1 and 91. The bone loss, bone density and utility of lamina dura were evaluated. The statistical analysis after three months evaluation using T-test for bone loss, Wilcoxon sign rank test for bone density and utility lamina dura showed no significantly differences (pchronic periodontitis with 2/3 alveolar bone loss after three months splinting.

Architectural Measures of the Cancellous Bone of the Mandibular Condyle Identified by Principal Components Analysis

DEFF Research Database (Denmark)

Giese, E.B.; Ding, M.; Dalstra, M.

2003-01-01

embalmed mandibular condyles; the angle of the first principal direction and the axis of the specimen, expressing the orientation of the trabeculae, ranged from 10 degrees to 87 degrees. Morphological parameters were determined by a method based on Archimedes' principle and by micro-CT scanning......-like trabeculae, and not with more or thicker trabeculae. The trabecular orientation was most determinative (about 50%) in explaining stiffness, strength, and failure energy. The amount of bone was second most determinative and increased the explained variance to about 72%. These results suggest that trabecular...

Orthodontic tooth movement after extraction of previously autotransplanted maxillary canines and ridge augmentation.

Science.gov (United States)

Collett, A R; Fletcher, B

2000-12-01

A case report is detailed in which autotransplanted maxillary canines were removed and the spaces closed. Substantial surrounding bone loss was associated with the upper right canine, and a bone graft was needed to reestablish normal dentoalveolar ridge morphology. Bone was taken from the maxillary tuberosity and placed in the canine extraction site, fixed with a bone screw, and covered with GoreTex. Seven months after placement of the bone graft, the GoreTex and stabilizing screw were removed to allow for consolidation of the bone. The upper left canine and lower second premolars were extracted, and fixed appliances were placed in both arches to align the teeth and close the spaces. Protraction of the upper right first premolar and retraction of the lateral incisor into the graft site were kept slow and constant with continued periodontal assessment. During the space closure, there was some concern that the bone in the graft site might resorb, leaving the teeth with compromised periodontal support. However, no significant periodontal attachment loss occurred despite ongoing concern about the amount of keratinized tissue. Perhaps the relatively slow rate of tooth movement provided for bone to be maintained and recreated ahead of the tooth. Almost complete closure of the upper canine extraction spaces was achieved. The upper premolars were substituted for the maxillary canines, and unfavorable prosthetic options were thus avoided. The lower arch was aligned, and the extraction spaces completely closed.

Eosinophilic granuloma of the mandibular condyle

International Nuclear Information System (INIS)

Huh, Kyung Hoe; Yi, Won Jin; Oh, Sung Won; Lee, Sam Sun; Choi, Mun Kyung

2008-01-01

The present study reports a case of eosinophilic granuloma of the mandibular condyle. Eosinophilic granulomas on the mandibular condyle are very rare, but there are several common clinical and radiographic presentations. The clinical presentations involve swelling on preauricular area, limitation of opening, TMJ pain, etc. The radiographic presentations involve radiolucent lytic condylar lesion with or without pathologic fracture. Sometimes new bone formations are observed. The purpose of the article is to add new cases to the literatures.

Eosinophilic granuloma of the mandibular condyle

Energy Technology Data Exchange (ETDEWEB)

Huh, Kyung Hoe; Yi, Won Jin; Oh, Sung Won; Lee, Sam Sun [Department of Oral and Maxillofacial Radiology, and Dental Research Institute, School of Dentistry, Seoul National University, Seoul (Korea, Republic of); Choi, Mun Kyung [Department of Oral and Maxillofacial Surgery, College of Medicine, Inje University Sanggye Paik Hospital, Seoul (Korea, Republic of)

2008-03-15

The present study reports a case of eosinophilic granuloma of the mandibular condyle. Eosinophilic granulomas on the mandibular condyle are very rare, but there are several common clinical and radiographic presentations. The clinical presentations involve swelling on preauricular area, limitation of opening, TMJ pain, etc. The radiographic presentations involve radiolucent lytic condylar lesion with or without pathologic fracture. Sometimes new bone formations are observed. The purpose of the article is to add new cases to the literatures.

Impacted canines: Etiology, diagnosis, and orthodontic management

Directory of Open Access Journals (Sweden)

Ranjit Manne

2012-01-01

Full Text Available Impaction of maxillary and mandibular canines is a frequently encountered clinical problem, the treatment of which usually requires an interdisciplinary approach. Surgical exposure of the impacted tooth and the complex orthodontic mechanisms that are applied to align the tooth into the arch may lead to varying amounts of damage to the supporting structures of the tooth, not to mention the long treatment duration and the financial burden to the patient. Hence, it seems worthwhile to focus on the means of early diagnosis and interception of this clinical situation. In the present article, an overview of the incidence and sequelae, as well as the surgical, periodontal, and orthodontic considerations in the management of impacted canines is presented.

Effect of plasma-rich in platelet-derived growth factors on peri-implant bone healing: An experimental study in canines

Science.gov (United States)

Birang, Reza; Torabi, Alireza; Shahabooei, Mohammad; Rismanchian, Mansour

2012-01-01

Background: Tissue engineering principles can be exploited to enhance alveolar and peri-implant bone reconstruction by applying such biological factors as platelet-derived growth factors. The objective of the present study is to investigate the effect of autologous plasma-rich in growth factors (on the healing of peri-implant bone in canine mandible). Materials and Methods: In this prospective experimental animal study, two healthy canines of the Iranian mix breed were selected. Three months after removing their premolar teeth on both sides of the mandible, 12 implants of the Osteo Implant Corporationsystem, 5 mm in diameter and 10 mm in length, were selected to be implanted. Plasma rich in growth factors (PRGF) were applied on six implants while the other six were used as plain implants without the plasma. The implants were installed in osteotomy sites on both sides of the mandible to be removed after 4 weeks with the surrounding bones using a trephine bur. Mesio-distal sections and implant blocks, 50 μ in diameter containing the peri-implant bone, were prepared By basic fuchin toluidine-bluefor histological and histomorphometric evaluation by optical microscope. The data were analyzed using Mann-Whitney Test (PPRGF and control groups had no statistically significant differences (P=0.261, P=0.2) although the parameters showed higher measured values in the PRGF group. However, compared to the control, application of PRGF had significantly increased bone-to-implant contact (P=0.028) Conclusion: Based on the results, it may be concluded that application of PRGF on the surface of implant may enhance bone-to-implant contact. PMID:22363370

Rapid palatal expansion effects on mandibular transverse dimensions in unilateral posterior crossbite patients: a three-dimensional digital imaging study

Directory of Open Access Journals (Sweden)

Alessandro Ugolini

2016-01-01

Full Text Available Abstract Background The purpose of this controlled study was to investigate indirect effects on mandibular arch dimensions, 1 year after rapid palatal expansion (RPE therapy. Methods Thirty-three patients in mixed dentition (mean age 8.8 years showing unilateral posterior crossbite and maxillary deficiency were treated with a RPE (Haas type cemented on the first permanent molars. Treatment protocol consisted of two turns per day until slight overcorrection of the molar transverse relationship occurred. The Haas expander was kept on the teeth as a passive retainer for an average of 6 months. Study models were taken prior (T1 and 15 months on average (T2 after expansion. A control group of 15 untreated subjects with maxillary deficiency (mean age 8.3 years was also recorded with a 12-month interval. Stone casts were digitized with a 3D scanner (3Shape, DK. Results In the treated group, both mandibular intermolar distance (+1.9 mm and mandibular molar angulation (+9° increased. Mandibular incisor angulation showed an increase of 1.9°. There was little effect on intercanine distance and canine angulation. Controls showed a reduction in transverse arch dimension and a decrease in molar and canine angulation values. Conclusions RPE protocol has indirect widening effects on the mandibular incisors and first molars.

Sex determination using cheiloscopy and mandibular canine index as a tool in forensic dentistry

Directory of Open Access Journals (Sweden)

B Bhagyashree

2018-01-01

Full Text Available Identification of a person′s individuality and sex determination are important for legal as well as identification purposes. The aim of the present study was to check the reliability of cheiloscopy and mandibular canine index (MCI in the determination of sex in an individual. The aim of this study is to analyze different lip patterns reproduced by the natural dye (vermilion and lysochrome (Sudan Black II dyes and to compare the MCI in males and females for the determination of sex and to check the reliability of cheiloscopy and MCI for the same. Latent lip prints were developed using natural dye (vermilion and lysochrome (Sudan Black II dyes and their patterns categorized according to Tsuchihashi′s classification. MCI were calculated. Analysis of the two was performed. According to discriminant functional analysis, percentage accuracy for cheiloscopy in the determination of sex was found to be 55% while for MCI, the same value was 85%. Natural dye (vermilion was found as an efficient dye compared to lysochrome (Sudan Black II dyes for the development of latent lip prints. Both the dyes showed Type I lip print pattern to be common in males and females. Furthermore, all the parameters in MCI were found to be significant in the determination of sex in an individual. The results of the present study revealed MCI to be more reliable in the determination of sex than cheiloscopy.

Characteristic Magnetic Resonance Imaging Findings in Rheumatoid Arthritis of the Temporomandibular Joint: Focus on Abnormal Bone Marrow Signal of the Mandibular Condyle, Pannus, and Lymph Node Swelling in the Parotid Glands.

Science.gov (United States)

Hirahara, Naohisa; Kaneda, Takashi; Muraoka, Hirotaka; Fukuda, Taiga; Ito, Kotaro; Kawashima, Yusuke

2017-04-01

The purpose of this study was to determine the characteristic magnetic resonance imaging (MRI) findings indicating bone and soft tissue involvement in patients with rheumatoid arthritis (RA) of the temporomandibular joints (TMJs). Twenty-one patients with RA and TMJ pain who underwent MRI examination of the TMJs at the authors' hospital from August 2006 to December 2014 were included in this study. Twenty-two patients with normal TMJs who underwent MRI examination at the authors' hospital from November to December 2014 were included as controls. MRI findings were compared between the 2 groups. MRI findings of RA in the TMJ included 1) abnormal disc position (95.2%), 2) abnormal disc morphology (83.3%), 3) joint effusion (30.9%), 4) osseous changes in the mandibular condyle (83.3%), 5) synovial proliferation (pannus; 85.7%), 6) erosion of the articular eminence and glenoid fossa (9.52%), 7) deformity of the articular eminence and glenoid fossa (16.6%), 8) abnormal bone marrow signal in the mandibular condyle (83.3%), and 9) swelling of lymph nodes in the parotid glands (78.5%). The abnormal bone marrow signal and pannus in the mandibular condyle and lymph node swelling in the parotid glands were markedly more common in patients with RA than in controls. MRI findings of RA of the TMJs were characterized by bone and soft tissue involvement, including abnormal bone marrow signal of the mandibular condyle, pannus, and swelling of lymph nodes in the parotid glands. These characteristic MRI findings could be useful in detecting RA in the TMJ in a clinical situation. Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

A role for subchondral bone changes in the process of osteoarthritis; a micro-CT study of two canine models

NARCIS (Netherlands)

Y.H. Sniekers (Yvonne); F. Intema (Femke); F.P.J.G. Lafeber (Floris); G.J.V.M. van Osch (Gerjo); J.P.T.M. van Leeuwen (Hans); H.H. Weinans (Harrie); S.C. Mastbergen (Simon)

2008-01-01

textabstractBACKGROUND: This study evaluates changes in peri-articular bone in two canine models for osteoarthritis: the groove model and the anterior cruciate ligament transection (ACLT) model. METHODS: Evaluation was performed at 10 and 20 weeks post-surgery and in addition a 3-weeks time point

Expression of nociceptive ligands in canine osteosarcoma.

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Shor, S; Fadl-Alla, B A; Pondenis, H C; Zhang, X; Wycislo, K L; Lezmi, S; Fan, T M

2015-01-01

Canine osteosarcoma (OS) is associated with localized pain as a result of tissue injury from tumor infiltration and peritumoral inflammation. Malignant bone pain is caused by stimulation of peripheral pain receptors, termed nociceptors, which reside in the localized tumor microenvironment, including the periosteal and intramedullary bone cavities. Several nociceptive ligands have been determined to participate directly or indirectly in generating bone pain associated with diverse skeletal abnormalities. Canine OS cells actively produce nociceptive ligands with the capacity to directly or indirectly activate peripheral pain receptors residing in the bone tumor microenvironment. Ten dogs with appendicular OS. Expression of nerve growth factor, endothelin-1, and microsomal prostaglandin E synthase-1 was characterized in OS cell lines and naturally occurring OS samples. In 10 dogs with OS, circulating concentrations of nociceptive ligands were quantified and correlated with subjective pain scores and tumor volume in patients treated with standardized palliative therapies. Canine OS cells express and secrete nerve growth factor, endothelin-1, and prostaglandin E2. Naturally occurring OS samples uniformly express nociceptive ligands. In a subset of OS-bearing dogs, circulating nociceptive ligand concentrations were detectable but failed to correlate with pain status. Localized foci of nerve terminal proliferation were identified in a minority of primary bone tumor samples. Canine OS cells express nociceptive ligands, potentially permitting active participation of OS cells in the generation of malignant bone pain. Specific inhibitors of nociceptive ligand signaling pathways might improve pain control in dogs with OS. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of American College of Veterinary Internal Medicine.

Class III malocclusion treated with distalization of the mandibular dentition with miniscrew anchorage: A 2-year follow-up.

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Chen, Kun; Cao, Yang

2015-12-01

This case report describes the orthodontic camouflage treatment for a 16-year-old Chinese girl with a Class III malocclusion. The treatment included extractions of the mandibular second molars, fixed appliance therapy, and miniscrew-aided mandibular arch distalization. Pretreatment, posttreatment, and 2-year follow-up records are shown. The anterior negative overjet and the Class III molar and canine relationships were corrected. The patient's facial profile was greatly improved. The mandibular third molars erupted into the second molar spaces, with acceptable intercuspation with the maxillary dentition. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

New hominin fossils from Kanapoi, Kenya, and the mosaic evolution of canine teeth in early hominins

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J. Michael Plavcan

2012-03-01

Full Text Available Whilst reduced size, altered shape and diminished sexual dimorphism of the canine–premolar complex are diagnostic features of the hominin clade, little is known about the rate and timing of changes in canine size and shape in early hominins. The earliest Australopithecus, Australopithecus anamensis, had canine crowns similar in size to those of its descendant Australopithecus afarensis, but a single large root alveolus has suggested that this species may have had larger and more dimorphic canines than previously recognised. Here we present three new associated dentitions attributed to A. anamensis, recently recovered from the type site of Kanapoi, Kenya, that provide evidence of canine evolution in early Australopithecus. These fossils include the largest mandibular canine root in the hominin fossil record. We demonstrate that, although canine crown height did not differ between these species, A. anamensis had larger and more dimorphic roots, more like those of extant great apes and Ardipithecus ramidus, than those of A. afarensis. The canine and premolar occlusal shapes of A. anamensis also resemble those of Ar. ramidus, and are intermediary between extant great apes and A. afarensis. A. afarensis achieved Homo-like maxillary crown basal proportions without a reduction in crown height. Thus, canine crown size and dimorphism remained stable during the early evolution of Australopithecus, but mandibular root dimensions changed only later within the A. anamensis–afarensis lineage, coincident with morphological changes in the canine–premolar complex. These observations suggest that selection on canine tooth crown height, shape and root dimensions was not coupled in early hominin evolution, and was not part of an integrated adaptive package.

99mTechnetium-methylene diphosphonate bone imaging using low-intensity pulsed ultrasound: promotion of bone formation during mandibular distraction osteogenesis in dogs.

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Ding, Yuxiang; Li, Guoquan; Ao, Jianhua; Zhou, Libin; Ma, Qin; Liu, Yanpu

2010-03-01

Our objective was to assess the value of (99m)technetium-methylene diphosphonate ((99m)Tc-MDP) bone imaging in the use of low-intensity pulsed ultrasound to promote bony formation during mandibular distraction osteogenesis in dogs. The body of the mandibles in 7 dogs were cut between the first and the second premolar and were lengthened at the rate of 1mm/day, twice a day, for 20 days. During the period of distraction one lateral distraction gap was irradiated with low-intensity pulsed ultrasound (LIPUS) for 10min twice a day, and the other side was used as control. Serial radiographic inspections were made at different periods (0, 1, 2, 4, 6, 8, and 12 weeks) during the consolidation phase, followed by a plain radiograph and histological examination. The (99m)Tc-MDP imaging showed that the ratio of bone formation on the LIPUS-treated side was significantly higher than that on the control side during the early period of consolidation (before the 4th week), but later this was reversed and there were no significant differences between the two sides by the 12th week. Plain radiographs and histological examination showed that the new bone on the experimental side had matured earlier than that on the control side. Radionuclide bone imaging is a good way to assess the formation of bone after distraction osteogenesis.

Dentoalveolar mandibular changes with self-ligating versus conventional bracket systems: A CBCT and dental cast study

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de Almeida, Marcio Rodrigues; Futagami, Cristina; Conti, Ana Cláudia de Castro Ferreira; Oltramari-Navarro, Paula Vanessa Pedron; Navarro, Ricardo de Lima

2015-01-01

OBJECTIVE: The aim of the present study was to compare dentoalveolar changes in mandibular arch, regarding transversal measures and buccal bone thickness, in patients undergoing the initial phase of orthodontic treatment with self-ligating or conventional bracket systems. METHODS: A sample of 25 patients requiring orthodontic treatment was assessed based on the bracket type. Group 1 comprised 13 patients bonded with 0.022-in self-ligating brackets (SLB). Group 2 included 12 patients bonded with 0.022-in conventional brackets (CLB). Cone-beam computed tomography (CBCT) scans and a 3D program (Dolphin) assessed changes in transversal width of buccal bone (TWBB) and buccal bone thickness (BBT) before (T1) and 7 months after treatment onset (T2). Measurements on dental casts were performed using a digital caliper. Differences between and within groups were analyzed by Student's t-test; Pearson correlation coefficient was also calculated. RESULTS: Significant mandibular expansion was observed for both groups; however, no significant differences were found between groups. There was significant decrease in mandibular buccal bone thickness and transversal width of buccal bone in both groups. There was no significant correlation between buccal bone thickness and dental arch expansion. CONCLUSIONS: There were no significant differences between self-ligating brackets and conventional brackets systems regarding mandibular arch expansion and changes in buccal bone thickness or transversal width of buccal bone. PMID:26154456

Mechanical properties of femoral trabecular bone in dogs

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Nolte Ingo

2005-03-01

Full Text Available Abstract Background Studying mechanical properties of canine trabecular bone is important for a better understanding of fracture mechanics or bone disorders and is also needed for numerical simulation of canine femora. No detailed data about elastic moduli and degrees of anisotropy of canine femoral trabecular bone has been published so far, hence the purpose of this study was to measure the elastic modulus of trabecular bone in canine femoral heads by ultrasound testing and to assess whether assuming isotropy of the cancellous bone in femoral heads in dogs is a valid simplification. Methods From 8 euthanized dogs, both femora were obtained and cubic specimens were cut from the centre of the femoral head which were oriented along the main pressure and tension trajectories. The specimens were tested using a 100 MHz ultrasound transducer in all three orthogonal directions. The directional elastic moduli of trabecular bone tissue and degrees of anisotropy were calculated. Results The elastic modulus along principal bone trajectories was found to be 11.2 GPa ± 0.4, 10.5 ± 2.1 GPa and 10.5 ± 1.8 GPa, respectively. The mean density of the specimens was 1.40 ± 0.09 g/cm3. The degrees of anisotropy revealed a significant inverse relationship with specimen densities. No significant differences were found between the elastic moduli in x, y and z directions, suggesting an effective isotropy of trabecular bone tissue in canine femoral heads. Discussion This study presents detailed data about elastic moduli of trabecular bone tissue obtained from canine femoral heads. Limitations of the study are the relatively small number of animals investigated and the measurement of whole specimen densities instead of trabecular bone densities which might lead to an underestimation of Young's moduli. Publications on elastic moduli of trabecular bone tissue present results that are similar to our data. Conclusion This study provides data about directional elastic

Radiological classification of mandibular fractures

International Nuclear Information System (INIS)

Mihailova, H.

2009-01-01

Mandibular fractures present the biggest part (up to 97%) of the facial bone fractures. Method of choice for diagnosing of mandibular fractures is conventional radiography. The aim of the issue is to present an unified radiological classification of mandibular fractures for the clinical practice. This classification includes only those clinical symptoms of mandibular fracture which could be radiologically objectified: exact anatomical localization (F1-F6), teeth in fracture line (Ta,Tb), grade of dislocation (D I, D II), occlusal disturbances (O(+), O(-)). Radiological symptoms expressed by letter and number symbols are systematized in a formula - FTDO of mandibular fractures similar to TNM formula for tumours. FTDO formula expresses radiological diagnose of each mandibular fracture but it doesn't include neither the site (left or right) of the fracture, nor the kind and number of fractures. In order to express topography and number of fractures the radiological formula is transformed into a decimal fraction. The symbols (FTD) of right mandible fracture are written in the numerator and those of the left site - in the denominator. For double and multiple fractures between the symbols for each fracture we put '+'. Symbols for occlusal disturbances are put down opposite, the fractional line. So topographo-anatomical formula (FTD/FTD)xO is formed. In this way the whole radiological information for unilateral, bilateral, single or multiple fractures of the mandible is expressed. The information in the radiological topography anatomic formula, resp. from the unified topography-anatomic classification ensures a quick and exact X-ray diagnose of mandibular fracture. In this way contributes to get better, make easier and faster X-ray diagnostic process concerning mandibular fractures. And all these is a precondition for prevention of retardation of the diagnosis mandibular fracture. (author)

Osteochondroma involving mandibular condyle

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Latika Bachani

2017-01-01

Full Text Available Osteochondroma is defined as an osteocartilagenous exostosis with cartilage capped exophytic lesion that arises from the bone cortex. It is a slow growing benign tumor that is rarely seen in the maxillofacial region. Osteochondroma of the mandibular condyle is a relatively rare condition that causes a progressive enlargement of the condyle, usually resulting in facial asymmetry, temporomandibular joint (TMJ dysfunction and malocclusion. Radiographically, there is a unilaterally enlarged condyle usually with an exophytic growth of the tumor from the condylar head. The treatment of osteochondroma is primarily surgical resection of the tumor. This paper reports a case of osteochondroma of the right mandibular condyle presenting as a painless restricted mouth opening.

Peer Reviewer

OpenAIRE

Baru Mansjur, Mansjur

2016-01-01

- Peer Reviewer Effects Of Histomorohometric, Bone Tu Implant Contac and Asseointegration On a novel Hybrid Micro/Nano Topografhy Modfie Dental Implant in The Mandibular Canine Premolar Area Of The Mini Pigs

Estudio experimental sobre la regeneración ósea mandibular de la rata con diferentes biomateriales Experimental study in rats of mandibular bone regeneration with different biomaterials

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B. Peral Cagigal

2008-10-01

Full Text Available Objetivo. Los defectos óseos mandibulares resultantes de infecciones, traumatismos o resecciones oncológicas, van a producir severos problemas funcionales y/o estéticos, que van a precisar de un tratamiento complejo. Durante los últimos años, las aportaciones al terreno de la reconstrucción ósea se han debatido entre métodos tan dispares como la distracción ósea o la utilización de colgajos libres microvascularizados, pasando por un sin fin de biomateriales. El objetivo de este estudio fue comparar la formación de hueso nuevo tras la aplicación de una membrana reabsorbible y dos tipos de sustitutivos óseos. Material y método. Se utilizaron 24 ratas adultas macho tipo Wistar, en las que se crearon defectos circulares de 4 mm de diámetro en ambos lados de la mandíbula. Se formaron 4 grupos, un grupo control y 3 grupos experimentales. Los animales fueron sacrificados a las 3 y 6 semanas de la cirugía, realizándose un análisis radiológico e histológico. Resultados. Los defectos control no mostraron formación ósea, apareciendo una reparación por tejido fibroso. La membrana de hueso utilizada de forma aislada, actuó como una barrera eficaz excluyendo los tejidos no osteogénicos, pero no se produjo reparación total del defecto en ningún caso. El grupo de Colloss® y membrana, mostró una regeneración ósea completa del defecto a las 6 semanas. El grupo de NovaBone® y membrana, no mostró formación ósea, apareciendo las partículas del biomaterial ocupando el defecto. Conclusiones. La regeneración ósea fue significativamente mayor en los defectos rellenos con Colloss® y cubiertos con la membrana de Lambone®, comparado con los otros grupos experimentales.Objective. Mandibular bone defects can occur as a result of trauma, neoplasm, or infectious conditions. Such conditions often are associated with severe funtional and esthetic problems. Corrective treatment often is complicated by limitations in tissue adaptation. The

Diverse bone morphogenetic protein expression profiles and smad pathway activation in different phenotypes of experimental canine mammary tumors.

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Helena Wensman

Full Text Available BACKGROUND: BMPs are currently receiving attention for their role in tumorigenesis and tumor progression. Currently, most BMP expression studies are performed on carcinomas, and not much is known about the situation in sarcomas. METHODOLOGY/PRINCIPAL FINDINGS: We have investigated the BMP expression profiles and Smad activation in clones from different spontaneous canine mammary tumors. Spindle cell tumor and osteosarcoma clones expressed high levels of BMPs, in particular BMP-2, -4 and -6. Clones from a scirrhous carcinoma expressed much lower BMP levels. The various clones formed different tumor types in nude mice but only clones that expressed high levels of BMP-6 gave bone formation. Phosphorylated Smad-1/5, located in the nucleus, was detected in tumors derived from clones expressing high levels of BMPs, indicating an active BMP signaling pathway and BMP-2 stimulation of mammary tumor cell clones in vitro resulted in activation of the Smad-1/5 pathway. In contrast BMP-2 stimulation did not induce phosphorylation of the non-Smad pathway p38 MAPK. Interestingly, an increased level of the BMP-antagonist chordin-like 1 was detected after BMP stimulation of non-bone forming clones. CONCLUSIONS/SIGNIFICANCE: We conclude that the specific BMP expression repertoire differs substantially between different types of mammary tumors and that BMP-6 expression most probably has a biological role in bone formation of canine mammary tumors.

Incidence and characteristics of mandibular accessory canals: A radiographic investigation.

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Borgonovo, Andrea Enrico; Taschieri, Silvio; Vavassori, Virna; Re, Dino; Francetti, Luca; Corbella, Stefano

2017-11-01

The aim of the present study was to explore, through tridimensional reconstructions of cone-beam computed tomography (CBCT) scans, the presence and the characteristics of mandibular accessory canals. For each included participant, the presence of accessory canals was recorded. The diameter of the canal, as well as the distance between the canal walls and the walls of the mandibular bone (lingual, buccal, cranial and caudal), were measured and recorded. Mandibular accessory canals could be found in 8.8% of participants. Retromolar canals were the most frequently found accessory mandibular canals. Accessory mandibular canals were found in a relatively high number of participants through the examination of CBCT scans and tridimensional reconstruction. The presence of such structures should be considered cautiously when planning and performing surgical interventions in mandibular area. © 2017 John Wiley & Sons Australia, Ltd.

Coralline hydroxyapatite bone graft substitutes in a canine metaphyseal defect model: Radiographic-biomechanical correlation

International Nuclear Information System (INIS)

Sartoris, D.J.; Resnick, D.; Holmes, R.E.; Tencer, A.F.; Texas Univ., Dallas; Mooney, V.

1986-01-01

Radiographic and biomechanical assessment of a new type of bone graft substitute derived from reef-building sea coral was performed in a canine metaphyseal defect model. Blocks of this material and autogenous iliac crest graft were implanted, respectively, into the right and left proximal tibial metaphyses of eight dogs. Qualitative and quantitative radiographic evaluation was performed in the immediate postoperative period and at 6 months after surgery. Biomechanical testing was carried out on all grafts following harvest at 6 months, as well as on nonimplanted coralline hydroxyapatite and autogenous iliac cancellous bone. In contrast to autografts, incorporation of coralline implants was characterized by predictable osseous growth and apposition with preservation of intrinsic architecture. Greater percent increase in radiography density, higher ultimate compressive strength, and lower stiffness with incorporation were documented advantages of coralline hydroxyapatite over autogenous graft. Densitometric measurements correlated moderately with strength for both types of graft material (r=0.65). These promising results have important implications to the clinical application of coralline hydroxyapatite bone graft substitutes as an alternative to autogenous grafting. (orig.)

Health of periodontal tissues and resorption status after orthodontic treatment of impacted maxillary canines.

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Oz, A Z; Ciger, S

2018-03-01

The aim of the present study was to evaluate the changes of incisor root resorption associated with impacted maxillary canines and health of periodontal tissues around maxillary canines erupted with orthodontic treatment. Twenty patients with a unilateral palatally impacted maxillary canine were included in the study. Cone-beam computed tomography images taken before and after orthodontic treatment were compared with the contralateral canines serving as control teeth. Root resorption was present in 10% of central and 40% of lateral incisors before treatment. After treatment, the incidence of resorption decreased. The thickness of the buccal bone surrounding the impacted canines was similar to that surrounding the contralateral canines, except in the apical area. Periodontal pocket depth and alveolar bone loss were greater for the impacted canine teeth than for the contralateral canines. Incisor root resorption associated with impacted canine teeth showed signs of repair after orthodontic treatment. Slight differences related to periodontal health were found between the previously impacted teeth and contralateral canine teeth.

Chest wall reconstruction in a canine model using polydioxanone mesh, demineralized bone matrix and bone marrow stromal cells.

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Tang, Hua; Xu, Zhifei; Qin, Xiong; Wu, Bin; Wu, Lihui; Zhao, XueWei; Li, Yulin

2009-07-01

Extensive chest wall defect reconstruction remains a challenging problem for surgeons. In the past several years, little progress has been made in this area. In this study, a biodegradable polydioxanone (PDO) mesh and demineralized bone matrix (DBM) seeded with osteogenically induced bone marrow stromal cells (BMSCs) were used to reconstruct a 6 cm x 5.5 cm chest wall defect. Four experimental groups were evaluated (n=6 per group): polydioxanone (PDO) mesh/DBMs/BMSCs group, polydioxanone (PDO) mesh/DBMs group, polydioxanone (PDO) mesh group, and a blank group (no materials) in a canine model. All the animals survived except those in the blank group. In all groups receiving biomaterial implants, the polydioxanone (PDO) mesh completely degraded at 24 weeks and was replaced by fibrous tissue with thickness close to that of the normal intercostal tissue (P>0.05). In the polydioxanone (PDO) mesh/DBMs/BMSCs group, new bone formation and bone-union were observed by radiographic and histological examination. More importantly, the reconstructed rib could maintain its original radian and achieve satisfactory biomechanics close to normal ribs in terms of bending stress (P>0.05). However, in the other two groups, fibrous tissue was observed in the defect and junctions, and the reconstructed ribs were easily distorted under an outer force. Based on these results, a surgical approach utilizing biodegradable polydioxanone (PDO) mesh in combination with DBMs and BMSCs could repair the chest wall defect not only in function but also in structure.

Interface mechanics and histomorphometric analysis of hydroxyapatite-coated and porous glass-ceramic implants in canine bone

DEFF Research Database (Denmark)

Nimb, L; Jensen, J S; Gotfredsen, K

1995-01-01

A canine study was performed to make a histological and biomechanical evaluation of the interface between bone and two different bioceramic implants. A newly developed glass-ceramic formed by P2O5, CaO, SiO2, and Al2O3, giving a crystal phase composed of CaP2O6-AlPO4-SiP2O7, was compared...... analysis. The ultimate shear strength for the HA-coated implants was significantly higher than in the glass-ceramic group. When these values were related to the histomorphometric measurements, the difference could be explained by the tissue-to-implant contact. The glass-ceramic showed direct contact only...... with nonmineralized, osteoid bone. The HA-coated implants, however, were integrated into the bone. The study indicated that porous glass-ceramic containing AlPO4 causes local osteomalacia and might not be suitable for clinical purposes....

Management of an endo perio lesion in a maxillary canine using platelet-rich plasma concentrate and an alloplastic bone substitute

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Singh Sangeeta

2009-01-01

Full Text Available To evaluate the efficacy of platelet-rich plasma concentrate in the management of a cirumferential, infrabony defect associated with an endoperio lesion in a maxillary canine. A 45 year-old male patient with an endoperio lesion in the left maxillary canine was initially treated with endodontic therapy. Following the endodontic treatment, the circumferential, infrabony defect was treated using platelet-rich plasma and an alloplastic bone substitute. At the end of three months, there was a gain in the clinical attachment level and reduction in probing depth. Radiographic evidence showed that there was significant bony fill. The results were maintained at the time of recall nine months later.

Miniscrew-assisted mandibular molar distalization in a patient with skeletal class-III malocclusion: A clinical case report

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Seyed Mohammadreza Safavi

2013-01-01

Full Text Available In nongrowing patients with mild skeletal Class-III malocclusion, premolar extraction or molar distalization in the lower arch can be done as a part of camouflage treatment. Temporary anchorage devices are widely used for this purpose because they do not produce undesirable reciprocal effects and do not depend on the patient′s cooperation. However, most reported cases in this regard have used interradicular miniscrews in the mandibular arch and these have a risk of failure as they can loosen due to collision with adjacent roots. This article showcases mandibular molar distalization utilizing miniscrews, inserted at the retromolar area to correct a Class-III problem. A 24-year-old girl with a mild skeletal Class-III malocclusion and dental Class-III molar and canine relationship bilaterally was referred for orthodontic treatment. The treatment plan included distalization of the lower molars bilaterally followed by full fixed appliance therapy, after third molar extractions. For the lower molar distalization, the miniscrews were inserted at the retromolar pad. At the end of 21 months, a Class-I molar and canine relationship, normal overjet and overbite were obtained. The average amount of distalization of mandibular first molar was 3.2 mm at the crown level. In conclusion, placing miniscrews at the retromolar pad area for lower molar distalization was found to be a simple and effective method for correcting anterior cross bite and mandibular anterior crowding or protrusion, without the need for patient compliance.

Cathepsin K expression and activity in canine osteosarcoma.

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Schmit, J M; Pondenis, H C; Barger, A M; Borst, L B; Garrett, L D; Wypij, J M; Neumann, Z L; Fan, T M

2012-01-01

Cathepsin K (CatK) is a lysosomal protease with collagenolytic activity, and its secretion by osteoclasts is responsible for degrading organic bone matrix. People with pathologic bone resorption have higher circulating CatK concentrations. Canine osteosarcoma (OS) cells will possess CatK, and its secretion will be cytokine inducible. Circulating CatK concentrations will be increased in dogs with OS, and will be a surrogate marker of bone resorption. Fifty-one dogs with appendicular OS and 18 age- and weight-matched healthy control dogs. In a prospective study, expressions of CatK mRNA and protein were investigated in OS cells. The inducible secretion and proteolytic activity of CatK from OS cells was assessed in vitro. Serum CatK concentrations were quantified in normal dogs and dogs with OS and its utility as a bone resorption marker was evaluated in dogs with OS treated with palliative radiation and antiresorptive agents. Canine OS cells contain preformed CatK within cytoplasmic vesicles. In OS cells, TGFβ1 induced the secretion of CatK, which degraded bone-derived type I collagen in vitro. CatK concentrations were higher in dogs with OS than healthy dogs (11.3 ± 5.2 pmol/L versus 8.1 ± 5.0 pmol/L, P = .03). In a subset of dogs with OS, pretreatment CatK concentrations gradually decreased after palliative radiation and antiresorptive treatment, from 9.3 ± 3.2 pmol/L to 5.0 ± 3.1 pmol/L, P = .03. Canine OS is associated with pathologic bone resorption, and CatK inhibitors might aid in the management of canine OS-related malignant osteolysis. Copyright © 2011 by the American College of Veterinary Internal Medicine.

[Stereomodel-assisted fibula free flap harvest and mandibular reconstruction: A technical note. Literature review of CAS and CAM applied to mandibular reconstruction.

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Pauchot, J; Lachat, J; Floret, F; Badet, J-M; Tavernier, L; Aubry, S

2013-08-05

Mandibular reconstruction with fibula free flap harvest is currently the reference technique. Various preoperative processes have been developed to optimize this reconstruction. We report our experience with a simple, inexpensive, preoperative technique requiring a 3D printer, a device for maintaining mandibular reduction, a paper-cutting guide. Stereomodels of the mandible were obtained from computed tomography scan data and printed 3D in ABS. It allowed planning mandibular osteotomies, determine the angle between two bone fragments, and preoperatively modeling the osteosynthesis plate. A paper-cutting guide, and a simple device for maintaining mandibular reduction were also built. Two patients were operated on with this technique, with follow-up at 6 and 8 months. Reconstructions were successful with good clinical outcome in terms of mandibular contour and reconstructed segments positions. Preoperative planning of reconstruction may be used for mandibular osteotomies, fibular osteotomies, maintaining mandibular reduction, osteosynthesis, or placing implants for dental rehabilitation. The most complex procedures can virtually plan all these steps, but they are expensive and long to implement. Nevertheless, such procedures are quite expansive and require time not always compatible with carcinoma. Using a mandibular stereomodel is fast, easy, and cheap. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Computer-aided design evaluation of harvestable mandibular bone volume: a clinical and tomographic human study.

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Verdugo, Fernando; Simonian, Krikor; Raffaelli, Luca; D'Addona, Antonio

2014-06-01

To evaluate and compare the volume of bone graft material that can be safely harvested from the mandibular symphysis and rami using a computer-aided design (CAD) software program. Preoperative computerized tomography scans from 40 patients undergoing bone augmentation procedures were analyzed. Symphysis and rami cross sections were mapped using a CAD software program (AutoCAD(®), Autodesk, Inc., San Rafael, CA, USA) to evaluate the bone volume that can be safely harvested. CAD calculations were contrasted to intrasurgical measurements in a subgroup of 20 individuals. CAD calculations yielded a safe harvestable osseous volume of 1.44 cm(3) ± 0.49 for the symphysis and 0.82 cm(3) ± 0.21 for each ramus (p < .0001, confidence interval [CI] 95%: 0.47-0.78). These measurements were significantly lower (p < .0001) than the bone volumes harvested intrasurgically for both symphysis and ramus, respectively (2.40 cm(3) ± 0.50 vs. 2.65 cm(3) ± 0.45). CAD calculations of harvestable symphysis and ramus bone translated into an average of 2.40 cm(3) ± 0.50 (range: 1.80-3.10 cm(3)) and 2.65 cm(3) ± 0.45 (range: 1.90-3.50) of particulate bone graft intrasurgically, respectively. Ramus cortical was significantly thicker than the symphysis cortical, 2.9 ± 0.4 mm versus 2.19 mm ± 0.4 mm (p < .0001, CI 95%: 0.45-1.03). The symphysis and rami are good harvesting sources to obtain dense corticocancellous bone. The significant volumetric CAD differences between the symphysis and ramus seem to balance out intrasurgically and may be due to the greater cortical bone volume at the ramus area. It is plausible to harvest an average of 7.70 cm(3) from the symphysis and rami alone. The use of a CAD software program can enhance surgical treatment planning prior to bone transplantation. © 2012 Wiley Periodicals, Inc.

[The para-clinic investigation of temporo-mandibular joint changes in patients with acromegaly].

Science.gov (United States)

Morăraşu, C; Burlui, V; Olaru, C; Boza, C; Bortă, C; Morăraşu, G; Brînză, M

2001-01-01

The Acromegaly is an endocrinological disease determined by the hypersecretion of STH in a certain period of the body evolution and it causes the hypertrophy of bones in general and of mandible and cranio-facial bones, determining a disorder due to this development of bones, associated with troubles in the activity of muscles and of the phospho-calcium metabolism. This study was made on a group of 33 acromegaly patients. Their temporo-mandibular joint was investigated by ortopantomography, tomography, computer tomography and scintigraphy. All of these exams shows the changes in temporo-mandibular joint due to the cells hyperactivity determined by the hypersecretion of STH.

Mandibular Deformity Correction by Distraction Osteogenesis

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Md Asaduzzaman

2011-02-01

Full Text Available Distraction osteogenesis (DO is a biological process of new bone formation. It could be used as an alternative treatment method for the correction of mandibular hypoplastic deformity. Modern distraction osteogenesis evolved primarily from the work of Gavriel llizarov. DO has been first applied to craniofacial region since McCarthy et al. In this case report, the patient was 17 years old male with bird face deformity due to hypoplasia of mandible resulted from bilateral TMJ ankylosis due to the fracture of both condyle at the age of 4 years. Patient’s intraincisal opening was absent 1 year back. He underwent condylectomy in both sides to release the ankylosis and to increase intraincisal opening. His mandibular length was markedly short. To increase his mandibular antero-posterior length, mandibular body distraction was done in Oral and Maxillofacial Surgery department, BSMMU. Through this procedure length of the body of mandibule was increased by 10 mm, occlusion was edge to edge and his lower facial appearance increased markedly. Mandibular body distraction osteogenesis was considerably effective when performed in a hypoplastic mandible to facilitate post-operative functional and esthetic restoration. Long term follow-up is necessary to evaluate relapse and complications. DOI: 10.3329/bsmmuj.v3i2.7061BSMMU J 2010; 3(2: 103-106

Mandibular unilateral fusion in primary dentition

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Neena Eregowda

2017-01-01

Full Text Available Fusion is a developmental anomaly which occurs due to a union of one or more adjacent teeth during morphodifferentiation of the dental germs. The prevalence of tooth fusion is estimated at 0.5%–2.5% in the primary dentition. These anomalies may be unilateral or bilateral and may affect either dentition although the deciduous teeth are more commonly affected. Early diagnosis of such condition is important because it may cause clinical problems, such as esthetic concerns, and caries. This report describes a case of unilateral fusion of the primary mandibular lateral incisor and canine and aims to evaluate any associated pathology.

Four osteotomy methods with piezosurgery to remove complicated mandibular third molars: a retrospective study.

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Ge, Jing; Yang, Chi; Zheng, Jia-Wei; He, Dong-Mei; Zheng, Ling-Yan; Hu, Ying-Kai

2014-11-01

Piezosurgery has been used widely in oral and maxillofacial surgery, but there has been no report systematically describing an osteotomy method with piezosurgery for complicated mandibular third molar removal. The aim of this study was to introduce 4 osteotomy methods using piezosurgery and evaluate their effects. A retrospective study was conducted of patients with a complicated impacted mandibular third molar requiring extraction. The predictor variable was the extraction technique. Four osteotomy methods using piezosurgery were tested according to different impaction types: method 1 involved complete bone removal; method 2 involved segmental bone removal; method 3 involved bone removal combined with tooth splitting; and method 4 involved block bone removal. Outcome variables were success rate, operative time, major complications (including nerve injury, mandible fracture, severe hematoma, or severe edema), and serious pyogenic infection. Data were analyzed using descriptive statistics. The study was composed of 55 patients with 74 complicated impacted mandibular third molars. All impacted mandibular third molars were removed successfully. The average surgical time was 15 minutes (range, 8 to 26 minutes). Thirty-eight molars (51.4%) were extracted by method 1, 18 molars (24.3%) by method 2, 12 molars (16.2%) by method 3, and 6 molars (8.1%) by method 4. Two cases (2.7%) developed postoperative infections and recovered within 1 week using drainage and antibiotic administration. The 4 osteotomy methods with piezosurgery provide effective ways of removing complicated impacted mandibular third molars. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Bone graft revascularization strategies

NARCIS (Netherlands)

Willems, W.F.

2014-01-01

Reconstruction of avascular necrotic bone by pedicled bone grafting is a well-known treatment with little basic research supporting its application. A new canine model was used to simulate carpal bone avascular necrosis. Pedicled bone grafting proved to increase bone remodeling and bone blood flow,

The effect of methotrexate on the bone healing of mandibular condylar process fracture: an experimental study in rats.

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Cavalcanti, Samantha Cristine Santos X B; Corrêa, Luciana; Mello, Suzana Beatriz Veríssimo; Luz, João Gualberto C

2014-10-01

Methotrexate (MTX) is an anti-metabolite used in rheumatology and oncology. High doses are indicated for oncological treatment, whereas low doses are indicated for chronic inflammatory diseases. This study evaluated the effect of two MTX treatment schedules on the bone healing of the temporomandibular joint fracture in rats. Seventy-five adult male Wistar rats were used to generate an experimental unilateral medially rotated condylar fracture model that allows an evaluation of bone healing and the articular structures. The animals were subdivided into three groups that each received one of the following treatments intraperitoneally: saline (1 mL/week), low-dose MTX (3 mg/kg/week) and high-dose MTX (30 mg/kg). The histological study comprised fracture site and temporomandibular joint evaluations and bone neoformation was evaluated by histomorphometric analysis. A biochemical parameter of bone formation was also assessed. When compared with saline, high-dose MTX delayed bone fracture repairs. In this latter group, after 90 days, the histological analysis revealed atrophy of the fibrocartilage and the presence of fibrous tissue in the joint space. The histomorphometric analysis revealed diminished bone neoformation. The alkaline phosphatase levels also decreased after MTX treatment. It was concluded that high-dose MTX impaired mandibular condyle repair and induced degenerative articular changes. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Roles of Chondrocytes in Endochondral Bone Formation and Fracture Repair

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Hinton, R.J.; Jing, Y.; Jing, J.; Feng, J.Q.

2016-01-01

The formation of the mandibular condylar cartilage (MCC) and its subchondral bone is an important but understudied topic in dental research. The current concept regarding endochondral bone formation postulates that most hypertrophic chondrocytes undergo programmed cell death prior to bone formation. Under this paradigm, the MCC and its underlying bone are thought to result from 2 closely linked but separate processes: chondrogenesis and osteogenesis. However, recent investigations using cell lineage tracing techniques have demonstrated that many, perhaps the majority, of bone cells are derived via direct transformation from chondrocytes. In this review, the authors will briefly discuss the history of this idea and describe recent studies that clearly demonstrate that the direct transformation of chondrocytes into bone cells is common in both long bone and mandibular condyle development and during bone fracture repair. The authors will also provide new evidence of a distinct difference in ossification orientation in the condylar ramus (1 ossification center) versus long bone ossification formation (2 ossification centers). Based on our recent findings and those of other laboratories, we propose a new model that contrasts the mode of bone formation in much of the mandibular ramus (chondrocyte-derived) with intramembranous bone formation of the mandibular body (non-chondrocyte-derived). PMID:27664203

In vivo bone strain in the mandibular corpus of Sapajus during a range of oral food processing behaviors.

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Ross, Callum F; Iriarte-Diaz, Jose; Reed, David A; Stewart, Thomas A; Taylor, Andrea B

2016-09-01

It has been hypothesized that mandibular corpus morphology of primates is related to the material properties of the foods that they chew. However, chewing foods with different material properties is accompanied by low levels of variation in mandibular strain patterns in macaques. We hypothesized that if variation in primate mandible form reflects adaptations to feeding on foods with different material and geometric properties, then this variation will be driven primarily by differences in oral food processing behavior rather than differences in chewing per se. To test this hypothesis, we recorded in vivo bone strain data from the lateral and medial surfaces of the mandibular corpus during complete feeding sequences in three adult male Sapajus as they fed on foods with a range of sizes and material properties. We assessed whether variation in mandibular corpus strain regimes is associated with variation in feeding behaviors and/or chewing on different foods, and we quantified the relative variation in mandibular corpus strain regimes associated with chewing on foods of different material properties versus a range of oral food processing behaviors (incisor, premolar, and molar biting; pulling on incisors; mastication). Feeding behavior had a significant effect on mandibular corpus strain regimes, as did chewing side and the cycle number in a feeding sequence. However, food type had weaker effects and usually only through interaction effects with chewing side and/or cycle type. Strain regimes varied most across different chew sides, then across different behaviors, and lastly between mastication cycles on different foods. Strain magnitudes associated with premolar, molar, and incisor biting were larger than those recorded during mastication. These data suggest that intra- and inter-specific variation in mandible morphology is a trade-off between performance requirements of different oral food processing behaviors and of variation in chewing side, with direct effects

Laser vs bur for bone cutting in impacted mandibular third molar surgery: A randomized controlled trial.

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Passi, Deepak; Pal, Uma Shankar; Mohammad, Shadab; Singh, Rakesh Kumar; Mehrotra, Divya; Singh, Geeta; Kumar, Manoj; Chellappa, Arul A L; Gupta, Chandan

2013-01-01

The aim of this study was to assess the feasibility of Er: YAG laser in bone cutting for removal of impacted lower third molar teeth and compare its outcomes with that of surgical bur. The study comprised 40 subjects requiring removal of impacted mandibular third molar, randomly categorized into two equal groups of 20 each, who had their impacted third molar removed either using Er: YAG laser or surgical bur as per their group, using standard methodology of extraction of impacted teeth. Clinical parameters like pain, bleeding, time taken for bone cutting, postoperative swelling, trismus, wound healing and complications were compared for both groups. Clinical parameters like pain, bleeding and swelling were lower in laser group than bur group, although the difference was statistically not significant. However, postoperative swelling showed significant difference in the two groups. Laser group required almost double the time taken for bone cutting with bur. Trismus persisted for a longer period in laser group. Wound healing and complications were assessed clinically and there was no significant difference in both the groups. Based on the results of our study, the possibility of bone cutting using lasers is pursued, the osteotomy is easily performed and the technique is better suited to minimally invasive surgical procedures. The use of Er: YAG laser may be considered as an alternative tool to surgical bur, specially in anxious patients.

Preradiation dental extractions and the incidence of bone necrosis

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Beumer, J.; Harrison, R.; Sanders, B.; Kurrasch, M.

1983-01-01

Studies were done with 120 patients submitting to preradiation dental extraction within the radiation treatment volume. Bone necroses developed at the extraction sites in 17 patients (14.1%). The risk of bone necrosis in these patients is primarily dependent upon the size of the radiation treatment volume, radiation dose to mandibular bone, and healing time for the extraction wounds. Of the 13 mandibular bone necroses occurring at preradiation extraction sites, only two have not responded favorably to conservative management. Our data indicates that a policy of selected tooth removal, before radiation treatment, will minimize the risk of osteoradionecrosis. Mandibular molars with advanced chronic periodontal bone loss, residing within the proposed radiation field should be considered for removal before commencement of radiation treatment

Evaluation of Pound concept in determination of mediolateral mandibular posterior teeth position

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Majid Naser Khaki

2017-03-01

Full Text Available Background: The ideal teeth arrangement is an important step for success in complete denture fabrication. There are different methods for determining the posterior denture teeth location. The purpose of this study was the comparison of posterior mandibular teeth location in the study group with Pound or Misch theory. Material and methods: An alginate mandibular impression of 80 dentate patients was taken and poured with dental stone. Retromolar pad area, mesial of canine and the lingual cusps of each posterior tooth marked on the cast and then transferred to the graded paper. Distance of each lingual cusp from the internal line of Pound triangle was measured. Data were analyzed with SPSS version 16.0. Result: In the study group, the average distance of lingual mandibular cusp from the internal line of Pound triangle was 1.69 mm in first premolars, 0.94 mm in second premolars, 0.7 mm in first molars and 0.75 mm in second molars. Conclusion: In most cases, distance of lingual mandibular cusps was within 1 mm of Pound triangle. Results were more similar to the Pound rather than the Misch theory.

Patient preference and satisfaction with implant-supported mandibular overdentures retained with ball or locator attachments: a crossover clinical trial.

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Krennmair, Gerald; Seemann, Rudolf; Fazekas, Andres; Ewers, Rolf; Piehslinger, Eva

2012-01-01

To determine patient satisfaction and preference for implant-supported mandibular overdentures (IOD) retained with ball or Locator attachments. In addition, peri-implant conditions and prosthodontic maintenance efforts for the final attachments were evaluated after 1 year of function. In this crossover clinical trial, 20 edentulous patients were recruited to receive two mandibular implants in the canine region and were provided with implant-retained mandibular overdentures and new complete maxillary dentures. Implant-retained mandibular overdentures were stabilized with either ball attachments or Locator attachments, in random order. After 3 months of function, the attachments in the existing denture were changed. Questionnaires on satisfaction/complaints with the prostheses were administered at baseline (with the old dentures) and after 3 months of function with each attachment, thus providing for an intraindividual comparison. The decision for the final attachment chosen was based on the patient's preference. For the definitive attachment, peri-implant conditions (peri-implant marginal bone resorption, pocket depth, and Plaque Index, Gingival Index, and Bleeding Index) as well as prosthodontic maintenance efforts and satisfaction score were evaluated after an insertion period of 1 year. Nineteen (95%) patients completed the study (1 dropout). Patient satisfaction improved significantly (P<.05) from baseline (old dentures) to the new prostheses retained with each of the two attachment types for all domains of satisfaction. However, there were no differences between ball or Locator attachment for any items of satisfaction evaluated and neither attachment had a significant patient preference. No differences for peri-implant parameters or for patient satisfaction were noted between the definitive attachments (ball, n=10; Locator, n=9) after 1 year. Although the overall incidence rate of prosthodontic maintenance did not significantly differ between both retention

Skeletal Class III malocclusion with thin symphyseal bone: a case report.

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Hikida, Eriko; Tanikawa, Chihiro

2012-11-01

To describe the management of a severe skeletal Class III patient with thin symphyseal bone and alveolar bone covering the mandibular incisors. A 24 year-old female presented with a skeletal Class III malocclusion characterised by thin alveolar bone in a mildly crowded, mandibular incisor region. Computerised tomography (CT) assisted in the determination of possible tooth movement within the anterior mandibular alveolar bone. The finalised treatment plan aimed to align the maxillary and mandibular dental arches following the extraction of the maxillary right first premolar and the mandibular right permanent lateral incisor. The surgical repositioning of the maxilla and mandible with a LeFort I osteotomy and a bilateral sagittal split osteotomy (BSSO) would follow. After treatment, an acceptable facial profile and a solid intercuspation of the teeth were obtained. Significant root resorption was not observed. The occlusion remained stable with normal overjet and overbite after two years of retention. CT examination provided an assessment of the three-dimensional morphological characteristics of anterior alveolar bone which enabled an evaluation of possible tooth movement.

Canine hip dysplasia: significance of early bony spurring

International Nuclear Information System (INIS)

Morgan, J.P.

1987-01-01

It is the purpose of this study to call attention to new bone production that often occurs early in the sequence of pathological changes associated with canine hip dysplasia. New bone production extending to bony remodeling, as well as femoral head subluxation, both occur in the sequence of pathologic changes associated with canine hip dysplasia. Subluxation is considered primary, while osteoarthrosis is a secondary feature, and both are used in the diagnosis of canine hip dysplasia. This report concerns the significance of the presence of a solitary bony osteophyte, or spur, that is frequently evident on the caudal aspect of the femoral neck as viewed on the conventional ventrodorsal projection. This report utilizes findings from pelvic radiographs of 605 dogs (five breeds). There was a greater frequency (54%)of this bony change in cases diagnosed radiographically as dysplastic than in cases diagnosed as normal(15%).Thus, it is suggested that this minimal radiographic change can be used as an indicator of early canine hip dysplasia, especially in the absence of subluxation of the femoral head

Is there a relation between local bone quality as assessed on panoramic radiographs and alveolar bone level?

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Nackaerts, Olivia; Gijbels, Frieda; Sanna, Anna-Maria; Jacobs, Reinhilde

2008-03-01

The aim was to explore the relation between radiographic bone quality on panoramic radiographs and relative alveolar bone level. Digital panoramic radiographs of 94 female patients were analysed (mean age, 44.5; range, 35-74). Radiographic density of the alveolar bone in the premolar region was determined using Agfa Musica software. Alveolar bone level and bone quality index (BQI) were also assessed. Relationships between bone density and BQI on one hand and the relative loss of alveolar bone level on the other were assessed. Mandibular bone density and loss of alveolar bone level were weakly but significantly negatively correlated for the lower premolar area (r = -.27). The BQI did not show a statistically significant relation to alveolar bone level. Radiographic mandibular bone density on panoramic radiographs shows a weak but significant relation to alveolar bone level, with more periodontal breakdown for less dense alveolar bone.

Mandibular Flexure in Anterior-Posterior and Transverse Plane on Edentulous Patients in Mashhad Faculty of Dentistry

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Azam Sadat Madani

2013-01-01

Full Text Available Introduction: Angle and internal position of lateral pterygoid muscle leads to contraction over two half of the mandible in maximum opening and protrusion position so it can affects impression prosthetic procedures. The aim of this study was to evaluate the mandibular flexure in two transverse and antro-posterior dimensions. Methods: Seventy edentulous patients at Mashhad Faculty of Dentistry as the main group and 50 dentulous patients as the control group were selected. In these patients, transverse dimensions between second molar areas and also canine eminence from one side to another side, and longitudinal dimensions based on the distance between canine to second molar area at centric occlusion and maximum mouth opening were measured. Dimensional differences as the mandibular flexure were measured. Results: The mandibular dimensions in maximum opening and closed mouth were different. Average reduction in transverse dimension on second molar region at maximum mouth opening and closing position were almost equal to -0.0787 mm for target group and 0.7512 mm for control group. On anterior side, averages of these changes were equal to 0.3069 mm for target group and were 0.2254 mm for control group. Conclusion: Transverse dimensions in anterior region at maximum opening position are smaller than the same dimension at closed mouth in edentulous and dentulous patients.

Hybrid approach to fabrication of hollow internally weighted mandibular denture: A case report.

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Hazari, Puja; Mishra, Sunil Kumar

2015-08-01

Preservation of ridge dimensions is critical for denture success. For long the concept of an internally weighted denture, which suggested that gravity and the additional weight to the mandibular complete denture aids in prosthetic retention is widely accepted. However, excessive weight and pressure can accelerate bone resorption. Here, we describe a unique modification of internally weighted metal denture base for the resorbed mandibular ridge with an incorporated additional hollow section over the anterior knife-edge ridge. The weight provided retention and stability while the hollow portion prevented further resorption of the bone.

Canine Platelet Lysate Is Inferior to Fetal Bovine Serum for the Isolation and Propagation of Canine Adipose Tissue- and Bone Marrow-Derived Mesenchymal Stromal Cells

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Russell, Keith A.; Gibson, Thomas W. G.; Chong, Andrew; Co, Carmon; Koch, Thomas G.

2015-01-01

Background Mesenchymal stromal cells (MSC) are increasingly investigated for their clinical utility in dogs. Fetal bovine serum (FBS) is a common culture supplement used for canine MSC expansion. However, FBS content is variable, its clinical use carries risk of an immune response, and its cost is increasing due to global demand. Platelet lysate (PL) has proven to be a suitable alternative to FBS for expansion of human MSC. Hypothesis and Objectives We hypothesized that canine adipose tissue (AT) and bone marrow (BM) MSC could be isolated and expanded equally in PL and FBS at conventionally-used concentrations with differentiation of these MSC unaffected by choice of supplement. Our objectives were to evaluate the use of canine PL in comparison with FBS at four stages: 1) isolation, 2) proliferation, 3) spontaneous differentiation, and 4) directed differentiation. Results 1) Medium with 10% PL was unable to isolate MSC. 2) MSC, initially isolated in FBS-supplemented media, followed a dose-dependent response with no significant difference between PL and FBS cultures at up to 20% (AT) or 30% (BM) enrichment. Beyond these respective peaks, proliferation fell in PL cultures only, while a continued dose-dependent proliferation response was noted in FBS cultures. 3) Further investigation indicated PL expansion culture was inducing spontaneous adipogenesis in concentrations as low as 10% and as early as 4 days in culture. 4) MSC isolated in FBS, but expanded in either FBS or PL, maintained ability to undergo directed adipogenesis and osteogenesis, but not chondrogenesis. Conclusions/Significance Canine PL did not support establishment of MSC colonies from AT and BM, nor expansion of MSC, which appear to undergo spontaneous adipogenesis in response to PL exposure. In vivo studies are warranted to determine if concurrent use of MSC with any platelet-derived products such as platelet-rich plasma are associated with synergistic, neutral or antagonistic effects. PMID:26353112

Canine Platelet Lysate Is Inferior to Fetal Bovine Serum for the Isolation and Propagation of Canine Adipose Tissue- and Bone Marrow-Derived Mesenchymal Stromal Cells.

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Keith A Russell

Full Text Available Mesenchymal stromal cells (MSC are increasingly investigated for their clinical utility in dogs. Fetal bovine serum (FBS is a common culture supplement used for canine MSC expansion. However, FBS content is variable, its clinical use carries risk of an immune response, and its cost is increasing due to global demand. Platelet lysate (PL has proven to be a suitable alternative to FBS for expansion of human MSC.We hypothesized that canine adipose tissue (AT and bone marrow (BM MSC could be isolated and expanded equally in PL and FBS at conventionally-used concentrations with differentiation of these MSC unaffected by choice of supplement. Our objectives were to evaluate the use of canine PL in comparison with FBS at four stages: 1 isolation, 2 proliferation, 3 spontaneous differentiation, and 4 directed differentiation.1 Medium with 10% PL was unable to isolate MSC. 2 MSC, initially isolated in FBS-supplemented media, followed a dose-dependent response with no significant difference between PL and FBS cultures at up to 20% (AT or 30% (BM enrichment. Beyond these respective peaks, proliferation fell in PL cultures only, while a continued dose-dependent proliferation response was noted in FBS cultures. 3 Further investigation indicated PL expansion culture was inducing spontaneous adipogenesis in concentrations as low as 10% and as early as 4 days in culture. 4 MSC isolated in FBS, but expanded in either FBS or PL, maintained ability to undergo directed adipogenesis and osteogenesis, but not chondrogenesis.Canine PL did not support establishment of MSC colonies from AT and BM, nor expansion of MSC, which appear to undergo spontaneous adipogenesis in response to PL exposure. In vivo studies are warranted to determine if concurrent use of MSC with any platelet-derived products such as platelet-rich plasma are associated with synergistic, neutral or antagonistic effects.

The mean visible labial length of maxillary and mandibular anterior teeth at rest

International Nuclear Information System (INIS)

Khan, F.; Abbas, M.

2014-01-01

To determine the mean visible labial length of maxillary and mandibular anterior teeth at rest. Study Design: Cross-sectional study. Place and Duration of Study: Department of Prosthodontics, Dr. Ishrat-ul-Ebad Khan Institute of Oral Health Sciences, Karachi, from October 2012 to March 2013. Methodology: A total of 200 subjects were included. Measurements were carried out using digital caliper from the border of the lip to the incisal edges of incisor and to the cusp tip for the canines. The length of the upper lip was measured from subnasale to stomion. Statistical analyses were performed by Mann Whitney-U test and Kruskal Walli's test. Results: The age of the participant ranged between 20 and 65 years. At rest, females significantly displayed more of the maxillary central incisor (2.93 +- 1.57 mm; p=0.003), lateral incisor (1.87 +- 1.12 mm; p=0.005) and canine (0.59 +- 0.62 mm; p=0.031). With increasing age, the amount of maxillary anterior teeth visible at rest significantly decreased (p < 0.001), and increased for the mandibular teeth (p < 0.001). Subjects with shorter upper lips significantly displayed more maxillary anterior incisor structure than subjects with longer upper lip (p < 0.001). Conclusion: Females displayed significantly more labial length of the maxillary anterior teeth. The mean visible labial length of maxillary anterior teeth significantly decreased with increasing age and increased for the mandibular teeth. As the upper lip length increased, the mean visible labial length of maxillary anterior teeth significantly decreased. (author)

Assessment of Alveolar Bone Status in Middle Aged Chinese (40-59 Years) with Chronic Periodontitis--Using CBCT.

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Zhao, Haijiao; Li, Chen; Lin, Li; Pan, Yaping; Wang, Hongyan; Zhao, Jian; Tan, Lisi; Pan, Chunling; Song, Jia; Zhang, Dongmei

2015-01-01

This study used con-beam computed tomography (CBCT) to investigate the prevalence and severity of alveolar bone loss in middle-aged (40-59 years) Chinese with chronic periodontitis. The study group comprised 145 dentate individuals aged 40 to 59 years residing in China who suffered from chronic periodontitis. CBCT and the application of NNT software were used to examine the level and location of alveolar bone loss. The study revealed that 40-59 year old patients with chronic periodontitis had severe bone loss. At 5,286 sites (34.7%), alveolar bone loss was mild; severe alveolar bone loss was found at 5,978 sites (39.2%). A comparison of bone loss in different jaws revealed that the area with the highest degree of bone loss was on the lingual side of the maxillary molar (56.3 ± 7.2%), and that the area with the lowest degree was primarily on the lingual side of the mandibular canine (27.5 ± 6.3%). There was a lower degree of alveolar bone loss in males than females. Differences were observed when comparing the incidence of bone loss between males and females (P chronic periodontitis, the highest degrees of bone loss in the incisors, premolars, and molars were on the lingual side, mesial side and lingual side, respectively. Menopause in females and smoking may affect the level of bone loss.

The impact on bone tissues of immediate implant-supported mandibular overdentures with cusped and cuspless teeth

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Khalid A. Arafa

2016-01-01

Full Text Available Objectives: To examine the effects on bone tissues of immediate implant-supported mandibular overdentures with cusped or cuspless teeth. Methods: A randomized controlled trial was conducted at the Dental Clinic, Faculty of Dentistry, Al-Azhar University, Assiut Branch, Egypt, over a 12-month period from September 2013 to September 2014. Twenty patients were treated with immediate implant-supported overdentures: one group received overdentures with cusped teeth, and the other group received overdentures with cuspless teeth. The rate of implant success was assessed clinically and radiographically at 3, 6, 9, and 12 months. The data were collected by a questionnaire, an observation checklist, and radiography. The data were then analyzed using computerized methods. Results: Overdentures with cusped teeth showed a significant improvement in the clinical criteria, including the absence of clinical implant mobility, pain, and bone resorption, while the clinical criteria for the absence of peri-implant radiolucency were insignificantly different between the 2 groups (p>0.05. There were no significant differences in the clinical evaluations for bone levels at the time of insertion or 3 months after insertions, while significant differences were found at 6, 9, and 12 months after insertion. Conclusion: Overdentures with cusped teeth supported by immediate implants were found superior regarding many clinical criteria than those cuspless counterparts.

The impact on bone tissues of immediate implant-supported mandibular overdentures with cusped and cuspless teeth.

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Arafa, Khalid A

2016-01-01

To examine the effects on bone tissues of immediate implant-supported mandibular overdentures with cusped or cuspless teeth. A randomized controlled trial was conducted at the Dental Clinic, Faculty of Dentistry, Al-Azhar University, Assiut Branch, Egypt, over a 12-month period from September 2013 to September 2014. Twenty patients were treated with immediate implant-supported overdentures: one group received overdentures with cusped teeth, and the other group received overdentures with cuspless teeth. The rate of implant success was assessed clinically and radiographically at 3, 6, 9, and 12 months. The data were collected by a questionnaire, an observation checklist, and radiography. The data were then analyzed using computerized methods.  Overdentures with cusped teeth showed a significant improvement in the clinical criteria, including the absence of clinical implant mobility, pain, and bone resorption, while the clinical criteria for the absence of peri-implant radiolucency were insignificantly different between the 2 groups (p more than 0.05). There were no significant differences in the clinical evaluations for bone levels at the time of insertion or 3 months after insertions, while significant differences were found at 6, 9, and 12 months after insertion. Overdentures with cusped teeth supported by immediate implants were found superior regarding many clinical criteria than those cuspless counterparts.

Characterization and Immunomodulatory Effects of Canine Adipose Tissue- and Bone Marrow-Derived Mesenchymal Stromal Cells.

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Keith A Russell

Full Text Available Mesenchymal stromal cells (MSC hold promise for both cell replacement and immune modulation strategies owing to their progenitor and non-progenitor functions, respectively. Characterization of MSC from different sources is an important and necessary step before clinical use of these cells is widely adopted. Little is known about the biology and function of canine MSC compared to their mouse or human counterparts. This knowledge-gap impedes development of canine evidence-based MSC technologies.We hypothesized that canine adipose tissue (AT and bone marrow (BM MSC (derived from the same dogs will have similar differentiation and immune modulatory profiles. Our objectives were to evaluate progenitor and non-progenitor functions as well as other characteristics of AT- and BM-MSC including 1 proliferation rate, 2 cell surface marker expression, 3 DNA methylation levels, 4 potential for trilineage differentiation towards osteogenic, adipogenic, and chondrogenic cell fates, and 5 immunomodulatory potency in vitro.1 AT-MSC proliferated at more than double the rate of BM-MSC (population doubling times in days for passage (P 2, AT: 1.69, BM: 3.81; P3, AT: 1.80, BM: 4.06; P4, AT: 2.37, BM: 5.34; P5, AT: 3.20, BM: 7.21. 2 Canine MSC, regardless of source, strongly expressed cell surface markers MHC I, CD29, CD44, and CD90, and were negative for MHC II and CD45. They also showed moderate expression of CD8 and CD73 and mild expression of CD14. Minor differences were found in expression of CD4 and CD34. 3 Global DNA methylation levels were significantly lower in BM-MSC compared to AT-MSC. 4 Little difference was found between AT- and BM-MSC in their potential for adipogenesis and osteogenesis. Chondrogenesis was poor to absent for both sources in spite of adding varying levels of bone-morphogenic protein to our standard transforming growth factor (TGF-β3-based induction medium. 5 Immunomodulatory capacity was equal regardless of cell source when tested in

Photoelastic Stress Analysis Surrounding Implant-Supported Prosthesis and Alveolar Ridge on Mandibular Overdentures

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Dorival Pedroso da Silva

2010-01-01

Full Text Available The purpose of this research was to evaluate the maximum stress around osseointegrated implants and alveolar ridge, in a mandible with left partial resection through a photoelastic mandibular model. The first group consisted of two implants: traditional model (T, implants placed in the position of both canines; fulcrum model (F, implants placed in the position of left canine CL and right lateral incisor LiR. Both models linked through a bar and clips. The second group was consisted of three implants, with implants placed in the position of both canines (CR and CL and the right lateral incisor (LiR, which composed four groups: (1 model with 3 “O” rings, (2 model 2 ERAs, bar with clips, (3 model 2 ERAs bar without clips; (4 model “O” ring bar and ERA. An axial and an oblique load of 6.8 kgf was applied on a overdenture at the 1st Pm, 2nd Pm, and 1st M. Results showed that the area around the left canine (CL was practically free of stress; the left lateral incisor (LiL developed only small tensions, and low stress in all the other cases; the right canine tooth suffered the largest concentrations of stress, mainly with the ERA retention mechanism.

Nonsurgical, nonextraction management of impacted maxillary canine

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Jasneet Singh

2018-01-01

Full Text Available NS, a 12 year 2 months old female patient, presented with the chief complaint of irregular teeth. Diagnosis revealed skeletal Class II jaw base relation, with average (toward vertical growth pattern, dentoalveolar angles Class I molar relationship with severe crowding in upper and moderate crowding in the lower arch, normally positioned maxillary incisors but proclined lower incisors, “V” shape constricted maxillary arch with first premolar in crossbite, overretained deciduous molar and a high placed buccoversion canine in the first quadrant and an impacted canine in the second quadrant, constricted mandibular arch with first premolar blocked out in the third quadrant. Treatment with a nonsurgical, nonextraction treatment plan by expansion of the upper arch and taking advantage of natural eruptive forces of the tooth was planned. The final outcome solved the patient's complaints and achieved an esthetically pleasing and functionally adequate occlusal result.

Adipose-derived stem cells and BMP-2 delivery in chitosan-based 3D constructs to enhance bone regeneration in a rat mandibular defect model.

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Fan, Jiabing; Park, Hyejin; Lee, Matthew K; Bezouglaia, Olga; Fartash, Armita; Kim, Jinku; Aghaloo, Tara; Lee, Min

2014-08-01

Reconstructing segmental mandiblular defects remains a challenge in the clinic. Tissue engineering strategies provide an alternative option to resolve this problem. The objective of the present study was to determine the effects of adipose-derived stem cells (ASCs) and bone morphogenetic proteins-2 (BMP-2) in three-dimensional (3D) scaffolds on mandibular repair in a small animal model. Noggin expression levels in ASCs were downregulated by a lentiviral short hairpin RNA strategy to enhance ASC osteogenesis (ASCs(Nog-)). Chitosan (CH) and chondroitin sulfate (CS), natural polysaccharides, were fabricated into 3D porous scaffolds, which were further modified with apatite coatings for enhanced cellular responses and efficient delivery of BMP-2. The efficacy of 3D apatite-coated CH/CS scaffolds supplemented with ASCs(Nog-) and BMP-2 were evaluated in a rat critical-sized mandibular defect model. After 8 weeks postimplantation, the scaffolds treated with ASCs(Nog-) and BMP-2 significantly promoted rat mandibular regeneration as demonstrated by micro-computerized tomography, histology, and immunohistochemistry, compared with the groups treated with ASCs(Nog-) or BMP-2 alone. These results suggest that our combinatorial strategy of ASCs(Nog-)+BMP-2 in 3D apatite microenvironments can significantly promote mandibular regeneration, and these may provide a potential tissue engineering approach to repair large bony defects.

The correlation between metacarpal bone mineral content and bone mineral density of the jawbone in implant patients

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Kuroda, Toshinobu; Takamori, Hitoshi; Yosue, Takashi

2006-01-01

This study estimated the relationship between metacarpal bone mineral content and jawbone density. The subjects were 141 patients who desired implant treatment and had undergone a thorough pre-operative CT examination. In the maxilla, bone mineral density (BMD) was measured at the cancellous bone between the nasal cavity and the maxillary sinus. In the mandible, BMD was measured at the cancellous bone beneath the mental foramen. The CT numbers were corrected by the quantitative computer tomography (QCT) method. Furthermore, the cortical indices of the mandible, i.e. C-PMI (Central-Panoramic Mandibular Index), and MCW (Mandibular Cortical Width) were measured and calculated from panoramic radiographs. The bone mineral content of the total body was obtained by ΣGS/D and MCI through Microdensitometry. The following results were obtained. Between the maxillary BMD and ΣGS/D and between the mandibular BMD and ΣGS/D, there was a correlation in females but no correlation in males. Between the maxillary BMD and MCI, there was a correlation in females but no correlation in males. However, in the mandibular BMD and MCI there was no correlation in females and males. Between C-PMI and ΣGS/D there was a correlation in both females and males. Between C-PMI and MCI there was a correlation in both females and males. Between MCW and ΣGS/D there was a correlation in both females and males. Between MCW and MCI there was a correlation in females, but no correlation in males. From the above results, it was concluded that the maxillary BMD and the cortical index of the mandible reflected changes in the metacarpal bone mineral content, while mandibular BMD did not. (author)

A morphological study of the mandibular molar region using reconstructed helical computed tomographic images

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Tsuno, Hiroaki; Noguchi, Makoto; Noguchi, Akira; Yoshida, Keiko; Tachinami, Yasuharu

2010-01-01

This study investigated the morphological variance in the mandibular molar region using reconstructed helical computed tomographic (CT) images. In addition, we discuss the necessity of CT scanning as part of the preoperative assessment process for dental implantation, by comparing the results with the findings of panoramic radiography. Sixty patients examined using CT as part of the preoperative assessment for dental implantation were analyzed. Reconstructed CT images were used to evaluate the bone quality and cross-sectional bone morphology of the mandibular molar region. The mandibular cortical index (MCI) and X-ray density ratio of this region were assessed using panoramic radiography in order to analyze the correlation between the findings of the CT images and panoramic radiography. CT images showed that there was a decrease in bone quality in cases with high MCI. Cross-sectional CT images revealed that the undercuts on the lingual side in the highly radiolucent areas in the basal portion were more frequent than those in the alveolar portion. This study showed that three-dimensional reconstructed CT images can help to detect variances in mandibular morphology that might be missed by panoramic radiography. In conclusion, it is suggested that CT should be included as an important examination tool before dental implantation. (author)

Prefabricated fibula free flap with dental implants for mandibular reconstruction.

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Pauchet, D; Pigot, J-L; Chabolle, F; Bach, C-A

2018-03-02

Free fibula transplant is routinely used for mandibular reconstruction in head and neck cancer. Dental rehabilitation, the objective of mandibular reconstruction, requires the use of dental implants as supports for fixed or removable dentures. Positioning of fibular bone grafts and implants determines implant osseointegration and the possibilities of dental rehabilitation. Prefabrication of a fibula free flap with dental implants prior to harvesting as a free flap can promote implant osseointegration. The position of the implants must then be precisely planned. Virtual surgery and computer-assisted design and prefabrication techniques are used to plan the reconstruction and then reproduce this planning by means of tailored fibula and mandible cutting guides, thereby ensuring correct positioning of fibular bone fragments and implants. The prefabricated fibula free flap technique requires two surgical procedures (prefabrication and flap transfer) and precise preoperative planning. Prefabricated fibula free flap with dental implants, by improving the quality of osseointegration of the implants before flap transfer, extends the possibilities of prosthetic rehabilitation in complex secondary mandibular reconstructions. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Cellular and Matrix Response of the Mandibular Condylar Cartilage to Botulinum Toxin.

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Eliane H Dutra

Full Text Available To evaluate the cellular and matrix effects of botulinum toxin type A (Botox on mandibular condylar cartilage (MCC and subchondral bone.Botox (0.3 unit was injected into the right masseter of 5-week-old transgenic mice (Col10a1-RFPcherry at day 1. Left side masseter was used as intra-animal control. The following bone labels were intraperitoneally injected: calcein at day 7, alizarin red at day 14 and calcein at day 21. In addition, EdU was injected 48 and 24 hours before sacrifice. Mice were sacrificed 30 days after Botox injection. Experimental and control side mandibles were dissected and examined by x-ray imaging and micro-CT. Subsequently, MCC along with the subchondral bone was sectioned and stained with tartrate resistant acid phosphatase (TRAP, EdU, TUNEL, alkaline phosphatase, toluidine blue and safranin O. In addition, we performed immunohistochemistry for pSMAD and VEGF.Bone volume fraction, tissue density and trabecular thickness were significantly decreased on the right side of the subchondral bone and mineralized cartilage (Botox was injected when compared to the left side. There was no significant difference in the mandibular length and condylar head length; however, the condylar width was significantly decreased after Botox injection. Our histology showed decreased numbers of Col10a1 expressing cells, decreased cell proliferation and increased cell apoptosis in the subchondral bone and mandibular condylar cartilage, decreased TRAP activity and mineralization of Botox injected side cartilage and subchondral bone. Furthermore, we observed reduced proteoglycan and glycosaminoglycan distribution and decreased expression of pSMAD 1/5/8 and VEGF in the MCC of the Botox injected side in comparison to control side.Injection of Botox in masseter muscle leads to decreased mineralization and matrix deposition, reduced chondrocyte proliferation and differentiation and increased cell apoptosis in the MCC and subchondral bone.

Mechanical properties of canine osteosarcoma-affected antebrachia.

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Steffey, Michele A; Garcia, Tanya C; Daniel, Leticia; Zwingenberger, Allison L; Stover, Susan M

2017-05-01

To determine the influence of neoplasia on the biomechanical properties of canine antebrachia. Ex vivo biomechanical study. Osteosarcoma (OSA)-affected canine antebrachia (n = 12) and unaffected canine antebrachia (n = 9). Antebrachia were compressed in axial loading until failure. A load-deformation curve was used to acquire the structural mechanical properties of neoplastic and unaffected specimens. Structural properties and properties normalized by body weight (BW) and radius length were compared using analysis of variance (ANOVA). Modes of failure were compared descriptively. Neoplastic antebrachia fractured at, or adjacent to, the OSA in the distal radial diaphysis. Unaffected antebrachia failed via mid-diaphyseal radial fractures with a transverse cranial component and an oblique caudal component. Structural mechanical properties were more variable in neoplastic antebrachia than unaffected antebrachia, which was partially attributable to differences in bone geometry related to dog size. When normalized by dog BW and radial length, strength, stiffness, and energy to yield and failure, were lower in neoplastic antebrachia than in unaffected antebrachia. OSA of the distal radial metaphysis in dogs presented for limb amputation markedly compromises the structural integrity of affected antebrachia. However, biomechanical properties of affected bones was sufficient for weight-bearing, as none of the neoplastic antebrachia fractured before amputation. The behavior of tumor invaded bone under cyclic loading warrants further investigations to evaluate the viability of in situ therapies for bone tumors in dogs. © 2017 The American College of Veterinary Surgeons.

Prediction of the size of unerupted canines and premolars in an Iranian population

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Mashaallah Khanehmasjedi

2013-01-01

Full Text Available Background and Aim: One of the important aspects of diagnosis and treatment planning in the mixed dentition is estimation of the size of unerupted permanent canines and premolars. One of the most commonly used the prediction methods are Tanaka and Johnston, which are based on data from a sample of Northern European descent children. The accuracy of this method when applied to a different ethnic population is questionable. The aim of this study was to determine the modified equations from Tanaka and Johnston for Iranian population. Materials and Methods: This study was an analytic and cross-sectional investigation with the randomized cluster sampling in Ahwaz. Fifty four students of 14-18 years age (32 girls, 22 boys were selected between 320 students and plaster models of their maxillary and mandibular arches were prepared. Subjects had fully erupted teeth, class I canine and molar relationship and presented no proximal caries or fillings, morphological anomalies, missing teeth or occlusal abrasion, and bruxism. The mesiodistal crown diameters of the permanent teeth were measured with using the sharpened boley gauge (accuracy 0.01 mm. The data were analyzed by using the regression correlation analyses and t-test. Results: The size of permanent canines and premolars were larger in maxilla than mandible and males than females. These values in Iran were different from other countries. Conclusion: In this study to predict the space (in mm required for alignment of unerupted canine and premolars in Iranian children, halve the sum of mesiodistal dimension of the four mandibular incisors and add the respective constants 10.5 for upper jaw and 10 for lower jaw.

Finite element analysis of rapid canine retraction through reducing resistance and distraction

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Junjie XUE

2014-01-01

Full Text Available Objective: The aims of this study were to compare different surgical approaches to rapid canine retraction by designing and selecting the most effective method of reducing resistance by a three-dimensional finite element analysis. Material and Methods: Three-dimensional finite element models of different approaches to rapid canine retraction by reducing resistance and distraction were established, including maxillary teeth, periodontal ligament, and alveolar. The models were designed to dissect the periodontal ligament, root, and alveolar separately. A 1.5 N force vector was loaded bilaterally to the center of the crown between first molar and canine, to retract the canine distally. The value of total deformation was used to assess the initial displacement of the canine and molar at the beginning of force loading. Stress intensity and force distribution were analyzed and evaluated by Ansys 13.0 through comparison of equivalent (von Mises stress and maximum shear stress. Results: The maximum value of total deformation with the three kinds of models occurred in the distal part of the canine crown and gradually reduced from the crown to the apex of the canine; compared with the canines in model 3 and model 1, the canine in model 2 had the maximum value of displacement, up to 1.9812 mm. The lowest equivalent (von Mises stress and the lowest maximum shear stress were concentrated mainly on the distal side of the canine root in model 2. The distribution of equivalent (von Mises stress and maximum shear stress on the PDL of the canine in the three models was highly concentrated on the distal edge of the canine cervix. . Conclusions: Removal of the bone in the pathway of canine retraction results in low stress intensity for canine movement. Periodontal distraction aided by surgical undermining of the interseptal bone would reduce resistance and effectively accelerate the speed of canine retraction.

[Principles of bone tissue structures interaction with full removable dentures fixed on intraosseous implantates modelling].

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Shashmurina, V R; Chumachenko, E N; Olesova, V N; Volozhin, A I

2008-01-01

Math modelling "removable dentures-implantate-bone" with size and density of bone tissue as variables was created. It allowed to study biomechanical bases of mandibular bone tissue structures interaction with full removable dentures of different constructions and fixed on intraosseous implantates. Analysis of the received data showed that in the majority of cases it was expedient to recommend 3 bearing (abutments) system of denture making. Rest on 4 and more implantates was appropriate for patients with reduced density of spongy bone and significant mandibular bone atrophy. 2 abutment system can be used in patients with high density of spongy bone and absence of mandibular bone atrophy.

Angiogenesis and bone regeneration of porous nano-hydroxyapatite/coralline blocks coated with rhVEGF165 in critical-size alveolar bone defects in vivo

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Du B

2015-03-01

Full Text Available Bing Du,1,2 Weizhen Liu,1 Yue Deng,1,3 Shaobing Li,1 Xiangning Liu,4 Yan Gao,1 Lei Zhou1 1Department of Oral Implantology, Guangdong Provincial Stomatological Hospital, Southern Medical University, Guangzhou, People’s Republic of China; 2Center of Stomatology, The First People’s Hospital of Foshan, Foshan, Guangdong, People’s Republic of China; 3Department of Oral and Maxillofacial Surgery, Qingdao Stomatological Hospital, Qingdao, People’s Republic of China; 4Department of Stomatology, The First Affiliated Hospital of Jinan University, Guangzhou, People’s Republic of China Abstract: To improve the regenerative performance of nano-hydroxyapatite/coralline (nHA/coral block grafting in a canine mandibular critical-size defect model, nHA/coral blocks were coated with recombinant human vascular endothelial growth factor165 (rhVEGF via physical adsorption (3 µg rhVEGF165 per nHA/coral block. After the nHA/coral blocks and VEGF/nHA/coral blocks were randomly implanted into the mandibular box-shaped defects in a split-mouth design, the healing process was evaluated by histological observation and histomorphometric and immunohistological analyses. The histological evaluations revealed the ingrowth of newly formed blood vessels and bone at the periphery and cores of the blocks in both groups at both 3 and 8 weeks postsurgery, respectively. In the histomorphometric analysis, the VEGF/nHA/coral group exhibited a larger quantity of new bone formation at 3 and 8 weeks postsurgery. The percentages of newly formed bone within the entire blocks in the VEGF/nHA/coral group were 27.3%±8.1% and 39.3%±12.8% at 3 weeks and 8 weeks, respectively, and these values were slightly greater than those of the nHA/coral group (21.7%±3.0% and 32.6%±10.3%, respectively, but the differences were not significant (P>0.05. The immunohistological evaluations revealed that the neovascular density in the VEGF/nHA/coral group (146±32.9 vessel/mm2 was much greater than

Digital design of scaffold for mandibular defect repair based on tissue engineering.

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Liu, Yun-feng; Zhu, Fu-dong; Dong, Xing-tao; Peng, Wei

2011-09-01

Mandibular defect occurs more frequently in recent years, and clinical repair operations via bone transplantation are difficult to be further improved due to some intrinsic flaws. Tissue engineering, which is a hot research field of biomedical engineering, provides a new direction for mandibular defect repair. As the basis and key part of tissue engineering, scaffolds have been widely and deeply studied in regards to the basic theory, as well as the principle of biomaterial, structure, design, and fabrication method. However, little research is targeted at tissue regeneration for clinic repair operations. Since mandibular bone has a special structure, rather than uniform and regular structure in existing studies, a methodology based on tissue engineering is proposed for mandibular defect repair in this paper. Key steps regarding scaffold digital design, such as external shape design and internal microstructure design directly based on triangular meshes are discussed in detail. By analyzing the theoretical model and the measured data from the test parts fabricated by rapid prototyping, the feasibility and effectiveness of the proposed methodology are properly verified. More works about mechanical and biological improvements need to be done to promote its clinical application in future.

Digital design of scaffold for mandibular defect repair based on tissue engineering

Institute of Scientific and Technical Information of China (English)

Yun-feng LIU; Fu-dong ZHU; Xing-tao DONG; Wei PENG

2011-01-01

Mandibular defect occurs more frequently in recent years,and clinical repair operations via bone transplantation are difficult to be further improved due to some intrinsic flaws.Tissue engineering,which is a hot research field of biomedical engineering,provides a new direction for mandibular defect repair.As the basis and key part of tissue engineering,scaffolds have been widely and deeply studied in regards to the basic theory,as well as the principle of biomaterial,structure,design,and fabrication method.However,little research is targeted at tissue regeneration for clinic repair operations.Since mandibular bone has a special structure,rather than uniform and regular structure in existing studies,a methodology based on tissue engineering is proposed for mandibular defect repair in this paper.Key steps regarding scaffold digital design,such as external shape design and internal microstructure design directly based on triangular meshes are discussed in detail.By analyzing the theoretical model and the measured data from the test parts fabricated by rapid prototyping,the feasibility and effectiveness of the proposed methodology are properly verified.More works about mechanical and biological improvements need to be done to promote its clinical application in future.

Surgical-orthodontic treatment of Class III malocclusion with agenesis of lateral incisor and unerupted canine

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Bruno Boaventura Vieira

2013-06-01

Full Text Available INTRODUCTION: Orthodontic-surgical treatment was performed in patient with skeletal Class III malocclusion due to exceeding mandibular growth. Patient also presented upper and lower dental protrusion, overjet of -3.0 mm, overbite of -1.0 mm, congenital absence of tooth #22, teeth #13 and supernumerary impaction, tooth #12 with conoid shape and partly erupted in supraversion, prolonged retention of tooth #53, tendency to vertical growth of the face and facial asymmetry. The discrepancy on the upper arch was -2.0 mm and -5.0 mm on the lower arch. METHODS: The pre-surgical orthodontic treatment was performed with extractions of the teeth #35 and #45. On the upper arch, teeth #53, #12 and supernumerary were extracted to accomplish the traction of the impacted canine. The spaces of the lower extractions were closed with mesialization of posterior segment. After aligning and leveling the teeth, extractions spaces closure and correct positioning of teeth on the bone bases, the correct intercuspation of the dental arch, with molars and canines in Angle's Class I, coincident midline, normal overjet and overbite and ideal torques, were evaluated through study models. The patient was submitted to orthognathic surgery and then the post-surgical orthodontic treatment was finished. RESULTS: The Class III malocclusion was treated establishing occlusal and facial normal standards.

Mandibular condylar morphology for bruxers with different grinding patterns.

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Tao, Jianxiang; Wu, Junhua; Zhang, Xuying

2016-07-01

The purpose of this study was to investigate the mandibular condylar morphology for bruxers with different grinding patterns. Condylar sectional morphology and condylar position of 30 subjects were determined by two viewers using cone beam computed tomography (CBCT) image data sets. The grinding patterns during sleep bruxism (SB) were determined objectively using a Brux-checker device.Chi-square tests were used for statistical analysis for the condylar morphology type between different tooth grinding patterns. Spearman's rank correlation coefficient was used for correlation analysis between condylar position and the canine guidance area during SB. Theincidence of condylarmorphologicaldivergence from idealwas35%.There isa significant difference in distribution of condylar morphology type between the group grinding (GG) and GG combined with mediotrusive side grinding (MG) (p < 0.05). There was no significant correlation between condylar position and canine guidance area during bruxism. MG during SB is associated with condylar morphology that is considered not to be ideal.

Clinical Comparison of Autogenous Bone Graft with and without Plasma Rich in Growth Factors in the Treatment of Grade II Furcation Involvement of Mandibular Molars

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Ardeshir Lafzi

2013-03-01

Full Text Available Background and aims. Plasma rich in growth factors (PRGF is a concentrated suspension of growth factors, which is used to promote periodontal tissue regeneration. The aim of this randomized, controlled, clinical trial was to evaluate of the treatment of grade II mandibular molar furcation involvement using autogenous bone graft with and without PRGF. Materials and methods. In this double-blind clinical trial, thirty mandibular molars with grade II furcation involvement in 30 patients were selected. The test group received bone graft combined with PRGF, while the control group was treated with bone graft only. Clinical parameters included clinical probing depth (CPD, vertical clinical attachment level (V-CAL, horizontal clinical attachment level (H-CAL, location of gingival margin (LGM, surgically exposed horizontal probing depth of bony defect (E-HPD, vertical depth of bone crest (V-DBC, vertical depth of the base of bony defect (V-DBD, and length of the intrabony defect (LID. After six months, a re-entry surgery was performed. Data were analyzed by SPSS 14, using Kolmogorov, Mann-Whitney U, and paired t-test. Results. After 6 months, both treatment methods led to significant improvement in V-CAL and H-CAL and significant decreases in CPD, E-HPD, V-DBD and LID; there was no significant difference in LGM and V-DBC in any of the treated groups compared to the baseline values. Also, none of the parameters showed significant differences between the study groups. Conclusion. Although autogenous bone grafts, with or without PRGF, were successful in treating grade II furcation involvement, no differences between the study groups were observed.

Clinical Comparison of Autogenous Bone Graft with and without Plasma Rich in Growth Factors in the Treatment of Grade II Furcation Involvement of Mandibular Molars

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Lafzi, Ardeshir; Shirmohammadi, Adileh; Faramarzi, Masoumeh; Jabali, Sahar; Shayan, Arman

2013-01-01

Background and aims Plasma rich in growth factors (PRGF) is a concentrated suspension of growth factors, which is used to promote periodontal tissue regeneration. The aim of this randomized, controlled, clinical trial was to evaluate of the treatment of grade II mandibular molar furcation involvement using autogenous bone graft with and without PRGF. Materials and methods In this double-blind clinical trial, thirty mandibular molars with grade II furcation involvement in 30 patients were selected. The test group received bone graft combined with PRGF, while the control group was treated with bone graft only. Clinical parameters included clinical probing depth (CPD), vertical clinical attachment level (V-CAL), horizontal clinical attachment level (H-CAL), location of gingival margin (LGM), surgically exposed horizontal probing depth of bony defect (E-HPD), vertical depth of bone crest (V-DBC), vertical depth of the base of bony defect (V-DBD), and length of the intrabony defect (LID). After six months, a re-entry surgery was performed. Data were analyzed by SPSS 14, using Kolmogorov, Mann-Whitney U, and paired t-test. Results After 6 months, both treatment methods led to significant improvement in V-CAL and H-CAL and significant decreases in CPD, E-HPD, V-DBD and LID; there was no significant difference in LGM and V-DBC in any of the treated groups compared to the baseline values. Also, none of the parameters showed significant differences between the study groups. Conclusion Although autogenous bone grafts, with or without PRGF, were successful in treating grade II furcation involvement, no differences between the study groups were observed. PMID:23486928

Analysis of Occlusal Vertical Dimension and Mandibular Basal Bone Height in a Nigerian Population

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Babatunde O. Akinbami

2014-01-01

Full Text Available Background. The actual basal bone height of the reconstructed mandible is relevant to achieve normal occlusal vertical dimension for the prosthesis fabricated. The purpose of the study was to determine the mean and baseline values of the occlusal vertical dimension and height of the mandibular basal bone in a Nigerian population. Method. Each participant was asked to bring the upper and lower teeth into contact, while the distance between the nasal sill and dimple on the lower lip was measured (OVD. The skin at lower border of the mandible was marked and the distance between this point and the landmark on the lower lip was measured, MBH. Result. 200 subjects were evaluated. Age range was 16–30 years, mean ± (SD, 21.6 ± (3.1 years. Males had mean ± (SD of 42.10 ± (5.34 mm for OVD and females 39.72 ± (5.25 mm; acceptable baseline range of OVD for any population will be 34–48 mm (3.4–4.8 cm. All the males had a mean ± (SD, 30.54 ± (6.13 mm for MBH, and all the females 29.63 ± (5.23 mm. Acceptable baseline range of MBH for any population will be 24–37 mm (2.4–3.7 cm. Conclusion. To reconstruct the mandible and still maintain the OVD, heights of bone grafts must not be less than 2 cm or greater than 4 cm.

Masticatory System Biomechanical Photoelastic Simulation fot the Comparision of the Conventional and Uni-Lock Systems in Mandibular Osteosynthesis

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Jose Luis Cebrian Carretero

2017-08-01

Full Text Available The biomechanical consequences of the interaction between titanium trauma plates and screws and the fractured mandible are still a matter of investigation. The mathematical and biomechanical models that have been developed show limitations and the experimental studies are not able to reproduce muscle forces and internal stress distributions in the bone-implant interface and mandibular structure. In the present article we show a static simulator of the masticatory system to demonstrate in epoxy resin mandibular models, by means of 3D (three-dimensional photoelasticity, the stress distribution using different osteosynthesis methods in the mandibular angle fractures. The results showed that the simulator and 3D photoelasticity were a useful method to study interactions between bone and osteosynthesis materials. The “Lock” systems can be considered the most favourable method due to their stress distribution in the epoxy resin mandible. 3D photoelasticity in epoxy resin models is a useful method to evaluate stress distribution for biomechanical studies. Regarding to mandibular osteosynthesis, “lock” plates offer the most favourable stress distribution due to being less aggressive to the bone

Algorithm of imaging modalities in cases of mandibular fractures

International Nuclear Information System (INIS)

Mihailova, H.

2009-01-01

Mandibular fracture is the most common bone fracture of maxillo-facial trauma. Up to now the main method for examination of the mandible is radiography. The aim of the issue is to present an algorithm of imaging modalities for investigation of patients in cases of mandibular trauma. It consists of series of X ray techniques and views of the facial skull named mandibulo-facial. This standardizes mandibulo-facial series includes exactly determined four projections done by conventional X ray techniques: posterior-anterior view of skull (PA or AP), oblique view of the left mandible; oblique view of the right mandible; occipito-mental view. Using these four planned radiograms is obligatory for each mandibular trauma. Panoramic X-ray is obligatory in cases of apparatus availability; this abolish only oblique views (left and right). Occipito-mental view of the skull gives anatomically better the coronoid process of the mandible, the zygoma complex, the orbital edges and maxillar sinus than Waters projection. So mandibulo-facial series of four planned radiograms is not only for diagnostic of mandibular fractures, but as a screening of mandibulo-facial trauma too. Thus using algorithm of imaging modalities in cases of mandibular fracture leads to optimization of diagnostic process in patients with mandibular trauma. (author)

A Prospective Study of Early Loaded Single Implant-Retained Mandibular Overdentures: Preliminary One-Year Results

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Ali M. El-Sheikh

2012-01-01

Full Text Available Purpose. To investigate the predictability of simplifying mandibular overdenture treatment using one-stage surgery and early prosthetic loading of a single implant. Materials and Methods. Twenty edentulous patients with problematic existing mandibular dentures were treated. A single implant with a chemically modified surface (SLActive, Straumann AG, Basel, Switzerland was placed into the mandibular midline. The patients were recalled at 3, 6 and 12 months. Clinical assessments and marginal bone loss using standardized radiographs were recorded. All complications, failures and maintenance were noted. Visual analog-scale questionnaires were used to record patient satisfaction in five categories. ANOVA was used to determine differences between means of marginal bone loss and different categories of patient staisfaction (=0.05. Results. The 20 early loaded implants were all surviving at the 12-month recall. All implants showed less than 1 mm of marginal bone loss by the end of the 1-year with a significant increase during the follow-up period. Few prosthetic problems were reported. Patient satisfaction was high with a significant increase in all comfort and functional parameters. Conclusions. These preliminary 1-year results indicate that early loading of a single chemically modified surface implant used to retain a mucosa-borne mandibular overdenture is a safe, reliable, and cost-effective treatment.

Post-traumatic changes of the temporo-mandibular joint by bone scintigraphy

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Harris, S.A.; Rood, J.P.; Testa, H.J.

1988-01-01

13 patients who sustained mandibular trauma were investigated with radiographs and scintiscans. The scintiscans showed abnormal uptake of radiopharmaceutical in the temporomandibular joint (TMJ). In patients with a long history of traumatic arthrosis, there was more positive correlation between the scintiscans, and clinical symptoms and histology than between radiographs, and symptoms and histology. In patients with mandibular body fractures and no TMJ symptoms, the scans showed abnormal uptake in the TMJ in 7/8 joints, in the absence of radiographic abnormality. The significance of the abnormal uptake and the value of scintigraphy is discussed.

Post-traumatic changes of the temporo-mandibular joint by bone scintigraphy

International Nuclear Information System (INIS)

Harris, S.A.; Rood, J.P.; Testa, H.J.

1988-01-01

13 patients who sustained mandibular trauma were investigated with radiographs and scintiscans. The scintiscans showed abnormal uptake of radiopharmaceutical in the temporomandibular joint (TMJ). In patients with a long history of traumatic arthrosis, there was more positive correlation between the scintiscans, and clinical symptoms and histology than between radiographs, and symptoms and histology. In patients with mandibular body fractures and no TMJ symptoms, the scans showed abnormal uptake in the TMJ in 7/8 joints, in the absence of radiographic abnormality. The significance of the abnormal uptake and the value of scintigraphy is discussed. (author)

Radiographic analysis of odontogenic cysts showing displacement of the mandibular canal

International Nuclear Information System (INIS)

Cho, Bong Hae

2003-01-01

To assess the radiographic findings of odontogenic cysts showing displacement of the mandibular canal using computed tomographic (CT) and panoramic images. CT and panoramic images of 63 odontogenic cysts (27 dentigerous, 16 odontogenic keratocysts, and 20 radicular cysts) were analyzed to evaluate the following parameters: the dimension and shape of the cysts, and the effect of the cysts on the mandibular canal and cortical plates. Of the 63 cysts examined in the study, 35 (55.6%) showed inferior displacement of the mandibular canal and 46 (73.0%) showed perforation of the canal. There were statistically significant differenced between CT and panoramic images in depicting displacement and perforation of the mandibular canal. Cortical expansion was seen in 46 cases (73.0%) and cortical perforation in 23 cases (36.5%). The radicular cysts showed cortical expansion and perforation less frequently than the other cyst groups. Large cysts of mandible should be evaluated by multiplanar CT images in order to detect the mandibular canal and cortical bone involvement.

Three-dimensional localization of impacted canines and root resorption assessment using cone beam computed tomography.

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Almuhtaseb, Eyad; Mao, Jing; Mahony, Derek; Bader, Rawan; Zhang, Zhi-xing

2014-06-01

The purpose of this study was to develop a new way to localize the impacted canines from three dimensions and to investigate the root resorption of the adjacent teeth by using cone beam computed tomography (CBCT). Forty-six patients undergoing orthodontic treatments and having impacted canines in Tongji Hospital were examined. The images of CBCT scans were obtained from KaVo 3D exam vision. Angular and linear measurements of the cusp tip and root apex according to the three planes (mid-sagittal, occlusal and frontal) have been taken using the cephalometric tool of the InVivo Dental Anatomage Version 5.1.10. The measurements of the angular and linear coordinates of the maxillary and mandibular canines were obtained. Using this technique the operators could envision the location of the impacted canine according to the three clinical planes. Adjacent teeth root resorption of 28.26 % was in the upper lateral incisors while 17.39% in upper central incisors, but no lower root resorption was found in our samples. Accurate and reliable localization of the impacted canines could be obtained from the novel analysis system, which offers a better surgical and orthodontic treatment for the patients with impacted canines.

Off-label use of rhBMP-2 as bone regeneration strategies in mandibular ameloblastoma unicystic.

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Silva, Henrique Celestino Lima E; Cheim, Adonai Peixoto; Moreno, Roberto; Miranda, Sérgio Luis de

2017-01-01

Jawbone reconstruction after tumor resection is one of the most challenging clinical tasks for maxillofacial surgeons. Osteogenic, osteoinductive, osteoconductive and non-antigenic properties of autogenous bone place this bone as the gold standard for solving problems of bone availability. However, the need for a second surgical site to harvest the bone graft increases significantly both the cost and the morbidity associated with the reconstructive procedures. Bone grafting gained an important tool with the discovery of bone morphogenetic proteins in 1960. Benefit of obtaining functional and real bone matrix without need of second surgical site seems to be the great advantage of use bone morphogenetic proteins. This study analyzed the use of rhBMP-2 in unicystic ameloblastoma of the mandible, detailing its structure, mechanisms of cell signaling and biological efficacy, in addition to present possible advantages and disadvantages of clinical use of rhBMP-2 as bone regeneration strategy. RESUMO A reconstrução óssea dos maxilares após ressecções tumorais é uma das tarefas mais difíceis para o cirurgião maxilofacial. As propriedades osteogênicas, osteoindutoras, osteocondutoras e não antigênicas do osso autógeno o colocam como o padrão-ouro para a solução de problemas de disponibilidade óssea. Entretanto a coleta do enxerto ósseo necessita de um segundo sítio cirúrgico, aumentando significativamente o custo e a morbidade associados ao procedimento reconstrutivo. A enxertia óssea ganhou uma excelente ferramenta com a descoberta das proteínas ósseas morfogenéticas na década de 1960. O benefício da obtenção de matriz óssea verdadeira e funcional, sem a necessidade de um segundo sítio cirúrgico, parece ser a grande vantagem do uso das proteínas ósseas morfogenéticas. Neste contexto, o objetivo deste estudo foi analisar a utilização da rhBMP-2 na regeneração óssea de ameloblastoma mandibular unicístico, detalhando sua estrutura, seus

Relationship among panoramic radiography findings, biochemical markers of bone turnover and hip bone mineral density in the diagnosis of postmenopausal osteoporosis

International Nuclear Information System (INIS)

Johari Khatoonabad, M.; Aghamohammadzade, N.; Taghilu, H.; Esmaeili, F.; Jabbari Khamnei, H.

2011-01-01

Recent investigations have shown that panoramic radiography might be a useful tool in the early diagnosis of osteoporosis. In addition, bone turnover biochemical marker might be valuable in predicting osteoporosis and fracture risks in the elderly, especially in post-menopausal women. The aim of the present study was to evaluate the relationship among the radio morphometric indices of the mandible, biochemical markers of the bone turnover and hip bone mineral density in a group of post-menopausal women. Patients and Methods: Evaluations of mandibular cortical width, mandibular cortical index, panoramic index and alveolar crest resorption ration (M/M ration) were carried out on panoramic radiographs of 140 post-menopausal women with an age range of 44-82 years. Hip bone mineral density was measured by dual-energy X-ray absorptiometry method. Bone mineral density values were divided into three groups of normal (T score>-1.0), Osteopenic (T score, -2.5 to -1.0) and Osteoporotic (T score<-2.5). Serum alkaline phosphatase and 25(OH) D3 were measured. Results: A decrease in mandibular cortical width by 1 mm increases the likelihood of osteopenia or osteoporosis up to 40%, having taken into consideration the effect of menopause duration. A 1 mm decrease in mandibular cortical width increased the likelihood of moderate or severe erosion of the lower cortex of the mandible up to 28% by taking age into consideration. The results did not demonstrate a statistically significant relationship between bone turnover markers and mandibular radio morphometric indices. Conclusion: Panoramic radiography gives sufficient information to make an early diagnosis regarding osteoporosis in post-menopausal women. Panoramic radiographs may be valuable in the prevention of osteoporotic fractures in elderly women.

Unexpectedly rapid evolution of mandibular shape in hominins.

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Raia, P; Boggioni, M; Carotenuto, F; Castiglione, S; Di Febbraro, M; Di Vincenzo, F; Melchionna, M; Mondanaro, A; Papini, A; Profico, A; Serio, C; Veneziano, A; Vero, V A; Rook, L; Meloro, C; Manzi, G

2018-05-09

Members of the hominins - namely the so-called 'australopiths' and the species of the genus Homo - are known to possess short and deep mandibles and relatively small incisors and canines. It is commonly assumed that this suite of traits evolved in early members of the clade in response to changing environmental conditions and increased consumption of though food items. With the emergence of Homo, the functional meaning of mandible shape variation is thought to have been weakened by technological advancements and (later) by the control over fire. In contrast to this expectation, we found that mandible shape evolution in hominins is exceptionally rapid as compared to any other primate clade, and that the direction and rate of shape change (from the ape ancestor) are no different between the australopiths and Homo. We deem several factors including the loss of honing complex, canine reduction, and the acquisition of different diets may have concurred in producing such surprisingly high evolutionary rates. This study reveals the evolution of mandibular shape in hominins has strong morpho-functional and ecological significance attached.

Mandibular pseudocarcinomatous hyperplasia.

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Warter, A; Walter, P; Meyer, C; Barrière, P; Galatir, L; Wilk, A

2000-08-01

Three unusual cases of pseudocarcinomatous (pseudoepitheliomatous) hyperplasia (PH) affecting chronic osteomyelitic mandibular sequestra are reported to highlight the differences with the various squamous neoplasms which occur in that site. In two patients carrying a mandibular graft following the excision of an ameloblastoma, mucosal ulcers resulted in chronic osteomyelitis. In a third patient, an apical dental infection was associated with fistulated osteomyelitis. Histology of the three sequestra showed an intraosseous squamous proliferation. It was characterized by a peripheral involvement of medullary spaces, the more mature epithelial layer covering the bone trabeculae without intervening stroma, and the basal type epithelial layer surrounding a central fibrovascular core. There were no histological or cytological signs of malignancy. PH shows an inverted pattern when compared with the centro-medullary tumoural islands seen in the various oral or odontogenic squamous neoplasms which occur in the jaws. The lack of signs of malignancy distinguish PH from common squamous cell carcinomas. A short clinical course is an important feature in the distinction of PH from the well differentiated squamous cell carcinomas which may develop in fistulated chronic osteomyelitis.

Studies on the position of canines, premolars and molars by 450 .deg. oblique lateral cephalography

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Ahn, Hyung Kyu [Department of Radiology, College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

1976-11-15

This study was done using the 45 .deg. oblique lateral cephalograms of 20 year old, 18 male and 27 female, with normal occlusion, on canines, premolars, premolars and molars on upper and lower jaws. Axial inclination to nasal floor, occlusal plane and mandibular plane, and inter-axial inclination were examined. In addition the position of each tooth was examined in height and depth in upper and lower jaws. The results were obtained as follows; 1. The inclination of long axis of upper lst premolar was most nearly perpendicular, upper canine was tilted mesially, and 2nd premolar and molars were tilted distally. 2. The inclination of long axis of lower molars were tilted mesially. 3. There were no severe variation on the inter-axial inclination of canine to 2nd molar.

Studies on the position of canines, premolars and molars by 450 .deg. oblique lateral cephalography

International Nuclear Information System (INIS)

Ahn, Hyung Kyu

1976-01-01

This study was done using the 45 .deg. oblique lateral cephalograms of 20 year old, 18 male and 27 female, with normal occlusion, on canines, premolars, premolars and molars on upper and lower jaws. Axial inclination to nasal floor, occlusal plane and mandibular plane, and inter-axial inclination were examined. In addition the position of each tooth was examined in height and depth in upper and lower jaws. The results were obtained as follows; 1. The inclination of long axis of upper lst premolar was most nearly perpendicular, upper canine was tilted mesially, and 2nd premolar and molars were tilted distally. 2. The inclination of long axis of lower molars were tilted mesially. 3. There were no severe variation on the inter-axial inclination of canine to 2nd molar.

Surgical Management of Mandibular Central Incisors with Dumbbell Shaped Periapical Lesion: A Case Report

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Roopadevi Garlapati

2014-01-01

Full Text Available Dental traumatic injuries may affect the teeth and alveolar bone directly or indirectly. Pulpal necrosis and chronic and apical periodontitis with cystic changes are the most common sequelae of the dental traumatic injuries, if the teeth are not treated immediately. This case report focuses on the conventional and surgical management of mandibular central incisors. A twenty-four-year-old male patient presented with pain in the mandibular central incisors. Radiographic examination revealed mandibular central incisors with dumbbell shaped periapical lesion. After root canal treatment, parendodontic surgery was performed for mandibular central incisors. After one-year recall examination, the teeth were asymptomatic and periapical lesion had healed.

Patterns of variation and covariation in the shapes of mandibular bones of juvenile salmonids in the genus Oncorhynchus

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Watson, Sawyer; Couture, Ryan B.; McKibben, Natasha S.; Nichols, James T.; Richardson, Shannon E.; Noakes, David L. G.

2016-01-01

SUMMARY What is the nature of evolutionary divergence of the jaw skeleton within the genus Oncorhynchus? How can two associated bones evolve new shapes and still maintain functional integration? Here, we introduce and test a ‘concordance’ hypothesis, in which an extraordinary matching of the evolutionary shape changes of the dentary and angular articular serves to preserve their fitting together. To test this hypothesis, we examined morphologies of the dentary and angular articular at parr (juvenile) stage, and at three levels of biological organization – between salmon and trout, between sister species within both salmon and trout, and among three types differing in life histories within one species, O. mykiss. The comparisons show bone shape divergences among the groups at each level; morphological divergence between salmon and trout is marked even at this relatively early life history stage. We observed substantial matching between the two mandibular bones in both pattern and amount of shape variation, and in shape covariation across species. These findings strongly support the concordance hypothesis, and reflect functional and/or developmental constraint on morphological evolution. We present evidence for developmental modularity within both bones. The locations of module boundaries were predicted from the patterns of evolutionary divergences, and for the dentary, at least, would appear to facilitate its functional association with the angular articular. The modularity results suggest that development has biased the course of evolution. PMID:26372063

Mesenchymal stem cells with rhBMP-2 inhibits the growth of canine osteosarcoma cells.

Science.gov (United States)

Rici, Rose Eli Grassi; Alcântara, Dayane; Fratini, Paula; Wenceslau, Cristiane Valverde; Ambrósio, Carlos Eduardo; Miglino, Maria Angelica; Maria, Durvanei Augusto

2012-02-22

The bone morphogenetic proteins (BMPs) belong to a unique group of proteins that includes the growth factor TGF-β. BMPs play important roles in cell differentiation, cell proliferation, and inhibition of cell growth. They also participate in the maturation of several cell types, depending on the microenvironment and interactions with other regulatory factors. Depending on their concentration gradient, the BMPs can attract various types of cells and act as chemotactic, mitogenic, or differentiation agents. BMPs can interfere with cell proliferation and the formation of cartilage and bone. In addition, BMPs can induce the differentiation of mesenchymal progenitor cells into various cell types, including chondroblasts and osteoblasts. The aim of this study was to analyze the effects of treatment with rhBMP-2 on the proliferation of canine mesenchymal stem cells (cMSCs) and the tumor suppression properties of rhBMP-2 in canine osteocarcoma (OST) cells. Osteosarcoma cell lines were isolated from biopsies and excisions of animals with osteosarcoma and were characterized by the Laboratory of Biochemistry and Biophysics, Butantan Institute. The mesenchymal stem cells were derived from the bone marrow of canine fetuses (cMSCs) and belong to the University of São Paulo, College of Veterinary Medicine (FMVZ-USP) stem cell bank. After expansion, the cells were cultured in a 12-well Transwell system; cells were treated with bone marrow mesenchymal stem cells associated with rhBMP2. Expression of the intracytoplasmic and nuclear markers such as Caspase-3, Bax, Bad, Bcl-2, Ki-67, p53, Oct3/4, Nanog, Stro-1 were performed by flow citometry. We evaluated the regenerative potential of in vitro treatment with rhBMP-2 and found that both osteogenic induction and tumor regression occur in stem cells from canine bone marrow. rhBMP-2 inhibits the proliferation capacity of OST cells by mechanisms of apoptosis and tumor suppression mediated by p53. We propose that rhBMP-2 has great

Management of periodontally compromised mandibular molar with Hemisectioning: A case report

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Bandu Napte

2014-01-01

Full Text Available Introduction: Hemisection involves sectioning of a periodontally involved mandibular molar so as to remove the involved root and save the remaining tooth. This procedure helps in saving a tooth which otherwise would have been deemed for extraction. Hemisection refers to removal or separation of root with its accompanying crown portion of two-rooted teeth, most commonly mandibular molars. Method: In this case report, an advanced Endo-Perio lesion on a left mandibular first molar was successfully treated by root-canal treatment and hemisection. This procedure helps preserve the tooth structure, alveolar bone and promote cost savings over other treatment options. Conclusion: Hemisection is a treatment option for saving a mandibular molar which is in advanced stage of periodontal disease of one root. Removal of the affected root will help in retaining the remaining tooth structure.

End-threaded intramedullary positive profile screw ended self-tapping pin (Admit pin) - A cost-effective novel implant for fixing canine long bone fractures.

Science.gov (United States)

Chanana, Mitin; Kumar, Adarsh; Tyagi, Som Prakash; Singla, Amit Kumar; Sharma, Arvind; Farooq, Uiase Bin

2018-02-01

The current study was undertaken to evaluate the clinical efficacy of end-threaded intramedullary pinning for management of various long bone fractures in canines. This study was conducted in two phases, managing 25 client-owned dogs presented with different fractures. The technique of application of end-threaded intramedullary pinning in long bone fractures was initially standardized in 6 clinical patients presented with long bone fractures. In this phase, end-threaded pins of different profiles, i.e., positive and negative, were used as the internal fixation technique. On the basis of results obtained from standardization phase, 19 client-owned dogs clinically presented with different fractures were implanted with end-threaded intramedullary positive profile screw ended self-tapping pin in the clinical application phase. The patients, allocated randomly in two groups, when evaluated postoperatively revealed slight pin migration in Group-I (negative profile), which resulted in disruption of callus site causing delayed union in one case and large callus formation in other two cases whereas no pin migration was observed in Group-II (positive profile). Other observations in Group-I was reduced muscle girth and delayed healing time as compared to Group-II. In clinical application, phase 21 st and 42 nd day post-operative radiographic follow-up revealed no pin migration in any of the cases, and there was no bone shortening or fragment collapse in end-threaded intramedullary positive profile screw ended self-tapping pin. The end-threaded intramedullary positive profile screw ended self-tapping pin used for fixation of long bone fractures in canines can resist pin migration, pin breakage, and all loads acting on the bone, i.e., compression, tension, bending, rotation, and shearing to an extent with no post-operative complications.

[Custom-made implant for complex facial reconstruction: A case of total replacement of temporo-mandibular joint, zygomatic arch and malar bone].

Science.gov (United States)

Guillier, D; Moris, V; See, L-A; Girodon, M; Wajszczak, B-L; Zwetyenga, N

2017-02-01

Total prosthetic replacement of the temporo-mandibular joint (TMJ) has become a common procedure, but it is usually limited to the TMJ itself. We report about one case of complex prosthetic joint reconstruction extending to the neighbouring bony structures. A 57-year-old patient, operated several times for a cranio-facial fibrous dysplasia, presented with a recurring TMJ ankylosis and a complexe latero-facial bone loss on the right side. We performed a reconstruction procedure including the TMJ, the zygomatic arch and the malar bone by mean of custom made composite prosthesis (chrome-cobalt-molybdenum-titanium and polyethylene). Five years postoperatively, mouth opening, nutrition, pain and oral hygiene were significantly improved. Nowadays technical possibilities allow for complex facial alloplastic reconstructions with good medium term results. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Osteogenesis Imperfecta Diagnosed from Mandibular and Lower Limb Fractures: A Case Report.

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Kobayashi, Yoshikazu; Satoh, Koji; Mizutani, Hideki

2016-06-01

Osteogenesis imperfecta (OI) is a congenital disease characterized by bone fragility and low bone mass. Despite the variety of its manifestation and severity, facial fractures occur very infrequently. Here, we report a case of an infant diagnosed with OI after mandibular and lower limb fractures. A boy aged 1 year and 3 months was brought to his neighboring hospital with a complaint of facial injury. He was transferred to our hospital to undergo operation 3 days later. Computed tomography images revealed multiple mandibular fractures including complete fracture in the symphysis and dislocated condylar fracture on the right side. Open reduction and internal fixation with absorbable implants was performed 7 days after injury. He fractured his right lower limb 2 months later. He was diagnosed with OI type IA by an orthopedist. He will be administered bone-modifying agents if he suffers from frequent fractures.

Toward Patient Specific Long Lasting Metallic Implants for Mandibular Segmental Defects

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Shayesteh Moghaddam, Narges

Mandibular defects may result from tumor resection, trauma, or inflammation. The goals of mandibular reconstruction surgeries are to restore mandible function and aesthetics. To this end, surgeons use a combination of bone grafts and metallic implants. These implants have drastically different mechanical properties than the surrounding bone. As a result, the stress distribution in the mandible changes after surgery. The long-term abnormal stress/strain distribution may lead to either graft failure due to bone resorption as a result of stress shielding, or hardware failure due to stress concentrations. During the healing period of six to nine months it is important that complete immobilization, bringing mandibular micro-motion down to the level of 200-500 mum during chewing, is achieved. After this period it is desired that bone undergo normal stress for long-term success of the treatment. Although current high stiffness fixation hardware accomplishes this immobilization during the healing period, the hardware continues to alter the normal stress-strain trajectory seen during chewing once the engrafted bone heals. Over the long-term, the immobilized and stress-shielded engrafted bone tends to resorb. On the other hand, hardware fracturing or/and screw loosening is observed as the stress is concentrated at certain locations on the hardware. Equally as important is the permanent loss of chewing power due to the altered stress-strain relationships. The first stage of this research is to study the problems encountered following a mandibular segmental defect reconstructive surgery. To this end, we constructed a finite element model of a healthy mandible, which includes cortical and cancellous bone, teeth (enamel and dentin components), and the periodontal ligament. Using this model, we studied a healthy adult mandible under maximum molar bite force for stress, strain, displacement, and reaction force distribution. For mandibular segmental defect reconstruction the

Anquilosis mandibular: una frecuente secuela por Noma Mandibular ankylosis: a Noma frequent sequel

Directory of Open Access Journals (Sweden)

R. Fernández García-Guilarte

2009-12-01

surgery. The surgical treatment performed consisted in ankylotic bone resection in all cases, accompanied with condrocostal graft reconstruction in one case. All patients continued postoperatively with an intensive physiotherapy. Clinically all patients showed an improvement in eating, chewing and speaking, obviously due to good occlusion. Low collaboration with the mandibular rehabilitation was the most common problem.

Vertical periodontal ligament distraction--a new method for aligning ankylosed and displaced canines.

Science.gov (United States)

Wilmes, Benedict; Drescher, Dieter

2009-05-01

In the course of a clinical pilot study we tested the vertical periodontal ligament (V-PDL) distraction as a means of aligning ankylosed upper canines. The objective of this study was to analyze the appropriateness und effectiveness of this method. The ankylosed upper canines of five female patients aged between 16 und 19 years were surgically exposed, luxated, and after a latency period of 5 to 7 days, distracted at a rate of 0.5 mm per day. The installed distractors were borne by the periodontal-mucosa, the periodontal-mucosa and the bone, or by the bone exclusively. We evaluated the distraction distance and time and degree of hard and soft tissue generation present in the region surrounding the distracted teeth. All canines were aligned after a mean distraction period of 43.2 days (+/- 3.6 days). The mean distraction distance was 10.8 mm. Three canines had defects at the cemento-enamel junction, and one canine had to be extracted due to a large defect at the root. Vertical PDL distraction is a minimally-invasive therapy to align ankylosed impacted canines. Even if the long-term prognosis of distracted canines with defects is uncertain, the patient benefits from the vertical PDL distraction because both hard and soft tissues are generated in the vicinity of the distracted canine.

Compensatory Cellular Reactions to Nonsteroidal Anti-Inflammatory Drugs on Osteogenic Differentiation in Canine Bone Marrow-Derived Mesenchymal Stem Cells

Science.gov (United States)

OH, Namgil; KIM, Sangho; HOSOYA, Kenji; OKUMURA, Masahiro

2014-01-01

ABSTRACT The suppressive effects of nonsteroidal anti-inflammatory drugs (NSAIDs) on the bone healing process have remained controversial, since no clinical data have clearly shown the relationship between NSAIDs and bone healing. The aim of this study was to assess the compensatory response of canine bone marrow-derived mesenchymal stem cells (BMSCs) to several classes of NSAIDs, including carprofen, meloxicam, indomethacin and robenacoxib, on osteogenic differentiation. Each of the NSAIDs (10 µM) was administered during 20 days of the osteogenic process with human recombinant IL-1β (1 ng/ml) as an inflammatory stimulator. Gene expression of osteoblast differentiation markers (alkaline phosphatase and osteocalcin), receptors of PGE2 (EP2 and EP4) and enzymes for prostaglandin (PG) E2 synthesis (COX-1, COX-2, cPGES and mPGES-1) was measured by using quantitative reverse transcription-polymerase chain reaction. Protein production levels of alkaline phosphatase, osteocalcin and PGE2 were quantified using an alkaline phosphatase activity assay, osteocalcin immunoassay and PGE2 immunoassay, respectively. Histologic analysis was performed using alkaline phosphatase staining, von Kossa staining and alizarin red staining. Alkaline phosphatase and calcium deposition were suppressed by all NSAIDs. However, osteocalcin production showed no significant suppression by NSAIDs. Gene expression levels of PGE2-related receptors and enzymes were upregulated during continuous treatment with NSAIDs, while certain channels for PGE2 synthesis were utilized differently depending on the kind of NSAIDs. These data suggest that canine BMSCs have a compensatory mechanism to restore PGE2 synthesis, which would be an intrinsic regulator to maintain differentiation of osteoblasts under NSAID treatment. PMID:24419976

Sternal Aspiration of Bone Marrow in Dogs: A Practical Approach for Canine Leishmaniasis Diagnosis and Monitoring

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Rosa Paparcone

2013-01-01

Full Text Available Bone-marrow aspirate material is commonly considered as one of the most sensitive tissues for a reliable diagnosis of leishmaniasis. The procedure herein described may permit less experienced veterinarians to be familiar with a quick and safe assessment method for leishmaniasis diagnosis in their patients. Animals are positioned in right lateral recumbency, and the area corresponding to the second, third, or fourth sternebra is identified and aseptically prepared. A 18-gauge needle connected to a 10 mL syringe is driven through the skin, up to the bone wall, and firmly pushed forward while rotating. Entry into the sternebra’s cavity is clearly perceived by the fall of resistance offered by the cortex. Some 2,500 sternal bone-marrow samplings were safely and efficiently performed on 887 dogs of different breeds and aging from 6 months to 14 years, during eight years of clinical activity for routine diagnosis of canine leishmaniasis in pets or for the efficacy evaluation of anti-Leishmania immunobiologicals in dogs naturally exposed to parasite transmission. Most of the samples (1716 were from 387 dogs enrolled for anti-Leishmania vaccine studies. The safety of the method was particularly assessed on these dogs that as per study protocol were submitted to repeated bone-marrow aspirations (2–4 per year in follow-up examinations.

An Investigation of Two Finite Element Modeling Solutions for Biomechanical Simulation Using a Case Study of a Mandibular Bone.

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Liu, Yun-Feng; Fan, Ying-Ying; Dong, Hui-Yue; Zhang, Jian-Xing

2017-12-01

The method used in biomechanical modeling for finite element method (FEM) analysis needs to deliver accurate results. There are currently two solutions used in FEM modeling for biomedical model of human bone from computerized tomography (CT) images: one is based on a triangular mesh and the other is based on the parametric surface model and is more popular in practice. The outline and modeling procedures for the two solutions are compared and analyzed. Using a mandibular bone as an example, several key modeling steps are then discussed in detail, and the FEM calculation was conducted. Numerical calculation results based on the models derived from the two methods, including stress, strain, and displacement, are compared and evaluated in relation to accuracy and validity. Moreover, a comprehensive comparison of the two solutions is listed. The parametric surface based method is more helpful when using powerful design tools in computer-aided design (CAD) software, but the triangular mesh based method is more robust and efficient.

Pediatric mandibular fractures: a free hand technique.

Science.gov (United States)

Davison, S P; Clifton, M S; Davison, M N; Hedrick, M; Sotereanos, G

2001-01-01

The treatment of pediatric mandibular fractures is rare, controversial, and complicated by mixed dentition. To determine if open mandibular fracture repair with intraoral and extraoral rigid plate placement, after free hand occlusal and bone reduction, without intermaxillary fixation (IMF), is appropriate and to discuss postoperative advantages, namely, maximal early return of function and minimal oral hygiene issues. A group of 29 pediatric patients with a mandibular fracture were examined. Twenty pediatric patients (13 males and 7 females) with a mean age of 9 years (age range, 1-17 years) were treated using IMF. All patients were treated by the same surgeon (G.S.). Surgical time for plating was reduced by 1 hour, the average time to place patients in IMF. The patients who underwent open reduction internal fixation without IMF ate a soft mechanical diet by postoperative day 3 compared with postoperative day 16 for those who underwent IMF. Complication rates related to fixation technique were comparable at 20% for those who did not undergo IMF and 33% for those who did. We believe that free hand reduction is a valuable technique to reduce operative time for pediatric mandibular fractures. It maximizes return to function while minimizing the oral hygiene issues and hardware removal of intermaxillary function.

Ossifying fibroma misdiagnosed as chronic apical periodontitis.

Science.gov (United States)

de Moraes Ramos-Perez, Flávia Maria; Soares, Ulysses Nicida; Silva-Sousa, Yara Teresinha Corrêa; da Cruz Perez, Danyel Elias

2010-03-01

Ossifying fibroma mimicking chronic apical periodontitis is extremely rare. This report describes a case of ossifying fibroma located in the periapical region of the mandibular right canine that was misdiagnosed as chronic apical periodontitis. A 40-year-old woman complained of slight pain in the right anterior mandibular region without mucosal abnormalities or swelling. Radiographically, a well-circumscribed, unilocular, radiolucent lesion was observed that was located in the periapical region of the mandibular right canine, which presented an endodontically treated root canal. Under local anesthesia, the lesion was fully excised. Microscopically, there was fibrocellular connective tissue associated with a mineralized component, which consisted of lamellar or trabecular and woven bone, compatible with the diagnosis of ossifying fibroma. Although it is very rare, ossifying fibroma should be considered in the differential diagnosis of unusual or persistent apical radiolucencies. Copyright (c) 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Hybrid approach to fabrication of hollow internally weighted mandibular denture: A case report

OpenAIRE

Hazari, Puja; Mishra, Sunil Kumar

2015-01-01

Preservation of ridge dimensions is critical for denture success. For long the concept of an internally weighted denture, which suggested that gravity and the additional weight to the mandibular complete denture aids in prosthetic retention is widely accepted. However, excessive weight and pressure can accelerate bone resorption. Here, we describe a unique modification of internally weighted metal denture base for the resorbed mandibular ridge with an incorporated additional hollow section ov...

Clinical importance of median mandibular flexure in oral rehabilitation: a review.

Science.gov (United States)

Sivaraman, K; Chopra, A; Venkatesh, S B

2016-03-01

The mandible has a property to flex inwards around the mandibular symphysis with change in shape and decrease in mandibular arch width during opening and protrusion of the mandible. The mandibular deformation may range from a few micrometres to more than 1 mm. The movement occurs because of the contraction of lateral pterygoid muscles that pulls mandibular condyles medially and causes a sagittal movement of the posterior segments. This movement of mandible can have a profound influence on prognosis and treatment outcome for various restorative, endodontics, fixed, removable and implant-related prosthesis. The review unfolds the causes, importance and clinical implications of median mandibular flexure in oral rehabilitation. This review also highlights the appropriate preventive measures and techniques that should be adopted by clinicians to minimise the effect of flexural movement of the jaw during oral rehabilitation. This would not only help clinicians to achieve a good prosthesis with accurate fit and longevity but also maintain the health of the surrounding periodontal or periimplant gingival tissues and bone. © 2015 John Wiley & Sons Ltd.

Indirect vs direct bonding of mandibular fixed retainers in orthodontic patients: Comparison of retainer failures and posttreatment stability. A 2-year follow-up of a single-center randomized controlled trial.

Science.gov (United States)

Egli, Fabienne; Bovali, Efstathia; Kiliaridis, Stavros; Cornelis, Marie A

2017-01-01

The objectives of this 2-arm parallel trial were to compare the numbers of failures of mandibular fixed retainers bonded with indirect and direct methods and to investigate the posttreatment changes 2 years after placement. Sixty-four consecutive patients from the postgraduate orthodontic clinic of the University of Geneva in Switzerland were randomly allocated to either an indirect or a traditional direct bonding procedure of a mandibular fixed retainer at the end of their orthodontic treatment (T0). Eligibility criteria were the presence of the 4 mandibular incisors and the 2 mandibular canines, and no active caries, restorations, fractures, or periodontal disease of these teeth. The patients were randomized in blocks of 4 (using an online randomization service) with allocation concealment secured by contacting the sequence generator for assignment. The patients were recalled 12 months and 24 months (T3) after retainer bonding. The main outcome was any first-time failure of retainers (ie, at least 1 composite pad debonded or fractured); unexpected posttreatment changes of the mandibular incisors and canines were a secondary outcome. Impressions and lateral cephalograms were taken at T0 and T3: changes in mandibular intercanine and interpremolar distances and mandibular incisor inclination were assessed. Blinding was applicable for outcome assessment only. The chi-square test and Cox regression were used to compare the survival rates of the retainers bonded with direct and indirect methods. Paired t tests were used to assess differences in intercanine and interpremolar distances and mandibular incisor inclination at T0 and T3. Significance was set at P direct bonding group (log-rank test, P = 0.64). The hazard ratio was 1.26 (95% confidence interval, 0.56-2.81; P = 0.58). Bond failures occurred mainly during the first year. There were no clinically significant changes in mandibular intercanine distance, interpremolar distance, and incisor inclination

Bone formation in cranial, mandibular, tibial and iliac bone grafts in rats

DEFF Research Database (Denmark)

Solheim, E; Pinholt, E M; Talsnes, O

1995-01-01

Several studies have suggested that grafts from membranous derived bone (e.g., calvarial grafts) retain their volume better than those from endochondral derived bone (e.g., iliac bone grafts). Increased osteogenesis in grafts of the former type has been offered as the explanation. However, simple...... volume measurements of the recovered grafts do not differentiate between viable and dead bone. We studied fresh syngeneic full-thickness bone grafts from calvaria, mandibula, tibia diaphysis, and iliac bone implanted in the back muscles of young Lewis rats. Bone formation in grafts recovered 3 weeks...... that the anatomical area of harvest is important regarding new bone formation in syngeneic bone grafts. However, the results do not support the contention that better maintenance of volume of calvarial grafts compared with iliac bone grafts is due to enhanced osteogenesis in the former....

Multiple myeloma presenting as mandibular pain

LENUS (Irish Health Repository)

Crowley, Miriam

2016-10-01

Introduction: Multiple myeloma (MM) is a systemic malignancy of plasma cells defined by monoclonal production of circulating immunoglobulins. Bone pain is a presenting feature in the majority of cases. Treatment may involve intravenous use of bisphosphonates, chemotherapy or haematopoietic stem cell transplantation. Here, we illustrate a first presentation of MM in a patient with mandibular pain and discuss radiographic, diagnostic and treatment challenges of orofacial issues in patients with MM.\\r\

Considerations of mandibular angle fractures during and after surgery for removal of third molars: a review of the literature.

Science.gov (United States)

Chrcanovic, Bruno Ramos; Custódio, Antônio Luís Neto

2010-06-01

Angle fractures are quite common considering that the angle of the mandible forms an area of lower resistance which contains a thicker upper border, a thin basilar bone, and the presence of an impacted mandibular third molar. Common complications of mandibular third molar surgery include alveolar osteitis (dry socket), secondary infection, nerve dysfunction, and hemorrhage. Reports of mandibular fracture during and after third molar removal are uncommon. The purpose of this paper is to discuss the risk and predisposing factors that should be analyzed regarding the possibility of immediate and late mandibular angle fractures and their need for surgical treatment as a means through which to remove impacted molars. This study is based on a thorough review of the literature as well as on one immediate and one late mandibular angle fracture as described by the authors' own personal experience. The danger of an immediate jaw fracture can be avoided by means of proper instrumentation and by refraining from excessive force on the bone. The tooth should be sectioned in such a way as to minimize the extent of bone removal and force caused by instrumentation. The danger of a late jaw fracture can be avoided by precise diagnosis in cases of patients over 25 years of age, particularly men, whose tooth roots are superimposed on or adjacent to the inferior alveolar canal on a panoramic image, any local pathology and systemic disease or medications which may impair bone strength, and patients who present bruxism and are active athletes.

Expression of Bcl-2 in canine osteosarcoma

Science.gov (United States)

Piro, F.; Leonardi, L.

2015-01-01

Osteosarcoma (OS) is the most common primary malignancy of bone. It is responsible for 80-85% of the primary bone tumors affecting dogs and it is characterized by aggressive and invasive behavior, with a high metastatic potential. Several studies on cancer and related tumorigenesis, show an involvement of the mechanisms of programmed cell death and cell survival. Many signals seem to be involved in the related mechanism of autophagy and in particular, our interest is focused on the expression of a family of Bcl-2 that seems to be involved either in the control of biomolecular mechanisms like autophagy and apoptosis. In this study we investigated the expression of Bcl-2 in different cases of spontaneous canine osteosarcoma and the related preliminary results are described. We found Bcl-2 activity was increased in OS tissue compared to normal bone tissue. These results suggested that Bcl-2 activity may play an important role in the formation of OS and as a diagnostic for neoplastic activity. However, further research is needed to confirm the role of Bcl-2 activity in OS in canines. PMID:26623359

Combination Therapy with Zoledronic Acid and Parathyroid Hormone Improves Bone Architecture and Strength following a Clinically-Relevant Dose of Stereotactic Radiation Therapy for the Local Treatment of Canine Osteosarcoma in Athymic Rats.

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Curtis, Ryan C; Custis, James T; Ehrhart, Nicole P; Ehrhart, E J; Condon, Keith W; Gookin, Sara E; Donahue, Seth W

2016-01-01

Clinical studies using definitive-intent stereotactic radiation therapy (SRT) for the local treatment of canine osteosarcoma (OSA) have shown canine patients achieving similar median survival times as the current standard of care (amputation and adjuvant chemotherapy). Despite this, there remains an unacceptable high risk of pathologic fracture following radiation treatment. Zoledronic acid (ZA) and parathyroid hormone (PTH) are therapeutic candidates for decreasing this fracture risk post-irradiation. Due to differing mechanisms, we hypothesized that the combined treatment with ZA and PTH would significantly improve bone healing more than ZA or PTH treatment alone. Using an orthotopic model of canine osteosarcoma in athymic rats, we evaluated bone healing following clinically-relevant doses of radiation therapy (12 Gy x 3 fractions, 36 Gy total). Groups included 36 Gy SRT only, 36 Gy SRT plus ZA, 36 Gy SRT plus ZA and PTH, 36 Gy SRT plus PTH, and 36 Gy SRT plus localized PTH treatment. Our study showed significant increases in bone volume and increased polar moments of inertia (in the distal femoral metaphysis) 8 weeks after radiation in the combined (ZA/PTH) treatment group as compared to radiation treatment alone. Histomorphometric analysis revealed evidence of active mineralization at the study endpoint as well as successful tumor-cell kill across all treatment groups. This work provides further evidence for the expanding potential indications for ZA and PTH therapy, including post-irradiated bone disease due to osteosarcoma.

Combination Therapy with Zoledronic Acid and Parathyroid Hormone Improves Bone Architecture and Strength following a Clinically-Relevant Dose of Stereotactic Radiation Therapy for the Local Treatment of Canine Osteosarcoma in Athymic Rats.

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Ryan C Curtis

Full Text Available Clinical studies using definitive-intent stereotactic radiation therapy (SRT for the local treatment of canine osteosarcoma (OSA have shown canine patients achieving similar median survival times as the current standard of care (amputation and adjuvant chemotherapy. Despite this, there remains an unacceptable high risk of pathologic fracture following radiation treatment. Zoledronic acid (ZA and parathyroid hormone (PTH are therapeutic candidates for decreasing this fracture risk post-irradiation. Due to differing mechanisms, we hypothesized that the combined treatment with ZA and PTH would significantly improve bone healing more than ZA or PTH treatment alone. Using an orthotopic model of canine osteosarcoma in athymic rats, we evaluated bone healing following clinically-relevant doses of radiation therapy (12 Gy x 3 fractions, 36 Gy total. Groups included 36 Gy SRT only, 36 Gy SRT plus ZA, 36 Gy SRT plus ZA and PTH, 36 Gy SRT plus PTH, and 36 Gy SRT plus localized PTH treatment. Our study showed significant increases in bone volume and increased polar moments of inertia (in the distal femoral metaphysis 8 weeks after radiation in the combined (ZA/PTH treatment group as compared to radiation treatment alone. Histomorphometric analysis revealed evidence of active mineralization at the study endpoint as well as successful tumor-cell kill across all treatment groups. This work provides further evidence for the expanding potential indications for ZA and PTH therapy, including post-irradiated bone disease due to osteosarcoma.

Cirugía de torus mandibular

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Manuel Ramon Osorio Castillo

2014-06-01

exostosis of the jaw are a precise example of them. For this reason there are speculative ideas about its pathogenesis, associated factors, incidence and prevalence and their need for treatment, which can create confusion among dental clinics for diagnosis and management. The torus as a benign bone tumor can occur in the jaw at the palate, jaw or in the level of internal tables; can appear anywhere in the skeleton. The TM is an exostosis or bone growth on the lingual surface of the jaw. This growth usually occurs near the milohyoided line, opposed the premolars, but it can extend from the canine to the first molar. The mucous membrane that covers tends to be thin and in general does not tolerate the forces of the prosthesis that are placed above them. The incidence of the torus of the jaw is low at 6% to 12.5% among Caucasians and people of African plain. So contrary, some authors report a much higher prevalence in the Colombian Atlantic coast. In this article is presented a case of male patient with bilateral mandibular torus, with many years of growth, even in situations that both phonetic and ulcerations repetitive decided to undergo surgery on a bilateral way. It is showed some considerations for handling this pathologic condition.Key Words: jawbone torus; exostosis; resective surgery.11-114.

Effect of Nonviral Plasmid Delivered Basic Fibroblast Growth Factor and Low Intensity Pulsed Ultrasound on Mandibular Condylar Growth: A Preliminary Study

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Harmanpreet Kaur

2014-01-01

Full Text Available Objective. Basic fibroblast growth factor (bFGF is an important regulator of tissue growth. Previous studies have shown that low intensity pulsed ultrasound (LIPUS stimulates bone growth. The objective of this study was to evaluate the possible synergetic effect of LIPUS and local injection of nonviral bFGF plasmid DNA (pDNA on mandibular growth in rats. Design. Groups were control, blank pDNA, bFGF pDNA, LIPUS, and bFGF pDNA + LIPUS. Treatments were performed for 28 days. Significant increase was observed in mandibular height and condylar length in LIPUS groups. MicroCT analysis showed significant increase in bone volume fraction in bFGF pDNA + LIPUS group. Histomorphometric analysis showed increased cell count and condylar proliferative and hypertrophic layers widths in bFGF pDNA group. Results. Current study showed increased mandibular condylar growth in either bFGF pDNA or LIPUS groups compared to the combined group that showed only increased bone volume fraction. Conclusion. It appears that there is an additive effect of bFGF + LIPUS on the mandibular growth.

Mesenchymal stem cells with rhBMP-2 inhibits the growth of canine osteosarcoma cells

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Grassi Rici Rose

2012-02-01

Full Text Available Abstract Background The bone morphogenetic proteins (BMPs belong to a unique group of proteins that includes the growth factor TGF-β. BMPs play important roles in cell differentiation, cell proliferation, and inhibition of cell growth. They also participate in the maturation of several cell types, depending on the microenvironment and interactions with other regulatory factors. Depending on their concentration gradient, the BMPs can attract various types of cells and act as chemotactic, mitogenic, or differentiation agents. BMPs can interfere with cell proliferation and the formation of cartilage and bone. In addition, BMPs can induce the differentiation of mesenchymal progenitor cells into various cell types, including chondroblasts and osteoblasts. The aim of this study was to analyze the effects of treatment with rhBMP-2 on the proliferation of canine mesenchymal stem cells (cMSCs and the tumor suppression properties of rhBMP-2 in canine osteocarcoma (OST cells. Osteosarcoma cell lines were isolated from biopsies and excisions of animals with osteosarcoma and were characterized by the Laboratory of Biochemistry and Biophysics, Butantan Institute. The mesenchymal stem cells were derived from the bone marrow of canine fetuses (cMSCs and belong to the University of São Paulo, College of Veterinary Medicine (FMVZ-USP stem cell bank. After expansion, the cells were cultured in a 12-well Transwell system; cells were treated with bone marrow mesenchymal stem cells associated with rhBMP2. Expression of the intracytoplasmic and nuclear markers such as Caspase-3, Bax, Bad, Bcl-2, Ki-67, p53, Oct3/4, Nanog, Stro-1 were performed by flow citometry. Results We evaluated the regenerative potential of in vitro treatment with rhBMP-2 and found that both osteogenic induction and tumor regression occur in stem cells from canine bone marrow. rhBMP-2 inhibits the proliferation capacity of OST cells by mechanisms of apoptosis and tumor suppression mediated by p

Temporo-mandibular joint condylectomy and its effect over occlusion in cats: cadaveric study.

Science.gov (United States)

El-Warrak, A O; Ferrer, G A; Lanthier, T; Loureiro Silva, B; El-Warrak, L O

2011-03-01

To determine the effect of unilateral condylectomy on dental occlusion in cats. Twelve feline cadaver heads were randomly submitted to either a right or left unilateral condylectomy of the temporo-mandibular joint. The distance between the mandibular and maxillary canine tooth was measured before (B0) and after the unilateral condylectomy (P0). A right or left latero--lateral standardised force (4 N) was applied to the mandibular mentus area before and after the surgical procedure. These measurements were analysed with a linear model for repeated measures. The comparative analysis between pre- and postsurgical values indicated no significant variation in teeth displacement following condylectomy between B0 and P0 measurements. Statistically significant differences were detected after either left or right condylectomy with respect to all measurements after application of the standardised forces. Occlusion changes are significant when comparing bites before and after surgery. Unilateral condylectomy causes a significant increase in latero-lateral amplitude of jaw movement which might clinically affect feline dental occlusion. Clinical studies are required to determine the effect of unilateral condylectomies on mastication and dental occlusion in feline patients. © 2011 British Small Animal Veterinary Association.

[Ex Vivo Testing of Mechanical Properties of Canine Metacarpal/Metatarsal Bones after Simulated Implant Removal].

Science.gov (United States)

Srnec, R; Fedorová, P; Pěnčík, J; Vojtová, L; Sedlinská, M; Nečas, A

2016-01-01

EXP, were compared and the difference was found to be statistically significant (p ≤ 0.05). CONCLUSIONS The recently developed biodegradable polymer-composite gel is easy and quick to apply to any defect, regardless of its shape, in bone tissue. The ex vivo mechanical tests on canine short bones showed that the composite applied to defects, which simulated holes left after screw removal, provided sufficient mechanical support to the bone architecture. The results of measuring maximum loading forces were statistically significant. However, before the composite could be recommended for use in veterinary or human medical practice, thorough pre-clinical studies will be required. fracture fixation, mechanical testing, bone plate, cortical screw, refracture.

Dentigerous Cyst Associated with Ectopic Canine and a ...

African Journals Online (AJOL)

ankylosis, cystic or neoplastic lesion or trauma may be the local factors ... After clinical and radiographic examination, a provisional diagnosis of ... bone along with the impacted teeth (permanent ectopic canine ... [7] Panoramic radiograph and ...

Evaluation of P16 expression in canine appendicular osteosarcoma.

Science.gov (United States)

Murphy, B G; Mok, M Y; York, D; Rebhun, R; Woolard, K D; Hillman, C; Dickinson, P; Skorupski, K

2017-06-20

Osteosarcoma (OSA) is a common malignant bone tumor of large breed dogs that occurs at predictable anatomic sites. At the time of initial diagnosis, most affected dogs have occult pulmonary metastases. Even with aggressive surgical treatment combined with chemotherapy, the majority of dogs diagnosed with OSA live less than 1 year from the time of diagnosis. The ability to identify canine OSA cases most responsive to treatment is needed. In humans, OSA is also an aggressive tumor that is histologically and molecularly similar to canine OSA. The expression of the tumor suppressor gene product P16 by human OSA tissue has been linked to a favorable response to chemotherapy. We identified an antibody that binds canine P16 and developed a canine OSA tissue microarray in order to test the hypothesis that P16 expression by canine OSA tissue is predictive of clinical outcome following amputation and chemotherapy. Although statistical significance was not reached, a trend was identified between the lack of canine OSA P16 expression and a shorter disease free interval. The identification of a molecular marker for canine OSA is an important goal and the results reported here justify a larger study.

Posterior Mandibular Ridge Resorption Associated with Different Retentive Systems for Overdentures: A 7-Year Retrospective Preliminary Study.

Science.gov (United States)

Elsyad, Moustafa Abdou; Mohamed, Shahinaz Sayed; Shawky, Ahmad Fathalla

This retrospective study compared posterior mandibular residual ridge resorption with two different retentive mechanisms for overdentures after 7 years. A convenience sample of 18 edentulous men was assigned to one of two equal groups. Two implants were placed in the mandibular canine areas for each patient using the conventional two-stage surgical protocol, and the implants were splinted with a round bar 3 months later. New mandibular overdentures were then connected to the bars with clips (clip-retained overdentures, CR group) or resilient liners (resilient liner-retained overdentures, RR group). Posterior mandibular ridge resorption (PMRR) was recorded using proportional measurements and posterior area index (PAI) on panoramic radiographs taken immediately after overdenture insertion (T 0 ) and 7 years later (T 7 ). A linear regression model was used to verify the relationship between PAI and the following considerations: attachment type, age, initial mandibular ridge height, period of mandibular edentulism, number of previously worn dentures, and relining events. After 7 years, the RR group demonstrated a significantly (P = .014) higher change in PAI (0.11 ± 0.02) than the CR group (0.06 ± 0.04). The average PMRR for each mm of posterior mandibular ridge was 0.79 mm (0.11 mm/year) in the CR group and 1.4 mm (0.2 mm/year) in the RR group. Attachment type, initial mandibular ridge height, and relining times were significantly correlated with change in the PAI (P = .004, P = .035, and P = .045, respectively). Within the limitations of this preliminary study's design, it was observed that following a 7-year period of use, resilient liner attachments for bar/implant-retained overdentures appear to be associated with greater posterior mandibular ridge resorption when compared to clip attachments.

Mandibular Two Mini Implants Overdenture Using Magnetic Attachments: A Case Report

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Anna Miyayasu

2017-12-01

Full Text Available Many patients with an edentulous mandible struggle to use complete dentures. The instability of such dentures caused by the lack of retention, often causes discomfort, as well as functional and psychosocial problems, which can be signifcantly improved using implant overdentures with retentive attachments. This case report describes a successful case of a mandibular implant overdenture using two mini implants and magnetic attachments for an elderly edentulous patient. Case Report: A 62-year-old female with a thin mandibular bone ridge presented with complaints of pain caused by an unstable and unretentive complete mandibular denture. This patient received two mini implants (diameter: 2.6 mm; length: 12 mm with magnetic attachments. After three months, magnetic assemblies with magnetic attraction of 400 gf were incorporated into the intaglio surface of her mandibular overdenture. At 11 months, magnetic attraction was changed from 400 gf to 600 gf to provide a stronger magnetic force for improving the retention of this denture. Conclusion: Based on a two-year follow-up period, the mandibular two mini implants overdenture with magnetic attachments was successful in improving the patient’s general satisfaction with her dentures

Bone regeneration by implantation of adipose-derived stromal cells expressing BMP-2

International Nuclear Information System (INIS)

Li Huiwu; Dai Kerong; Tang Tingting; Zhang Xiaoling; Yan Mengning; Lou Jueren

2007-01-01

In this study, we reported that the adipose-derived stromal cells (ADSCs) genetically modified by bone morphogenetic protein 2 (BMP-2) healed critical-sized canine ulnar bone defects. First, the osteogenic and adipogenic differentiation potential of the ADSCs derived from canine adipose tissue were demonstrated. And then the cells were modified by the BMP-2 gene and the expression and bone-induction ability of BMP-2 were identified. Finally, the cells modified by BMP-2 gene were applied to a β-tricalcium phosphate (TCP) carrier and implanted into ulnar bone defects in the canine model. After 16 weeks, radiographic, histological, and histomorphometry analysis showed that ADSCs modified by BMP-2 gene produced a significant increase of newly formed bone area and healed or partly healed all of the bone defects. We conclude that ADSCs modified by the BMP-2 gene can enhance the repair of critical-sized bone defects in large animals

Comparison of Piezosurgery and Conventional Rotary Instruments for Removal of Impacted Mandibular Third Molars: A Randomized Controlled Clinical and Radiographic Trial

Science.gov (United States)

Shokry, Mohamed; Aboelsaad, Nayer

2016-01-01

The purpose of this study was to test the effect of the surgical removal of impacted mandibular third molars using piezosurgery versus the conventional surgical technique on postoperative sequelae and bone healing. Material and Methods. This study was carried out as a randomized controlled clinical trial: split mouth design. Twenty patients with bilateral mandibular third molar mesioangular impaction class II position B indicated for surgical extraction were treated randomly using either the piezosurgery or the conventional bur technique on each site. Duration of the procedure, postoperative edema, trismus, pain, healing, and bone density and quantity were evaluated up to 6 months postoperatively. Results. Test and control sites were compared using paired t-test. There was statistical significance in reduction of pain and swelling in test sites, where the time of the procedure was statistically increased in test site. For bone quantity and quality, statistical difference was found where test site showed better results. Conclusion. Piezosurgery technique improves quality of patient's life in form of decrease of postoperative pain, trismus, and swelling. Furthermore, it enhances bone quality within the extraction socket and bone quantity along the distal aspect of the mandibular second molar. PMID:27597866

Comparison of Piezosurgery and Conventional Rotary Instruments for Removal of Impacted Mandibular Third Molars: A Randomized Controlled Clinical and Radiographic Trial

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Hani Arakji

2016-01-01

Full Text Available The purpose of this study was to test the effect of the surgical removal of impacted mandibular third molars using piezosurgery versus the conventional surgical technique on postoperative sequelae and bone healing. Material and Methods. This study was carried out as a randomized controlled clinical trial: split mouth design. Twenty patients with bilateral mandibular third molar mesioangular impaction class II position B indicated for surgical extraction were treated randomly using either the piezosurgery or the conventional bur technique on each site. Duration of the procedure, postoperative edema, trismus, pain, healing, and bone density and quantity were evaluated up to 6 months postoperatively. Results. Test and control sites were compared using paired t-test. There was statistical significance in reduction of pain and swelling in test sites, where the time of the procedure was statistically increased in test site. For bone quantity and quality, statistical difference was found where test site showed better results. Conclusion. Piezosurgery technique improves quality of patient’s life in form of decrease of postoperative pain, trismus, and swelling. Furthermore, it enhances bone quality within the extraction socket and bone quantity along the distal aspect of the mandibular second molar.

Recurrent osteochondroma of the mandibular condyle: A case report

International Nuclear Information System (INIS)

Kwon, Young Eun; Choi, Karp Shik; An, Chang Hyeon; Choi, So Young; An, Seo Young; Lee, Jae Seo

2017-01-01

A 21-year-old woman presented with facial asymmetry. Crepitus and clicking of the temporomandibular joint were noted. The midline deviated 5.5 mm to the left, and secondary malocclusion was observed. Panoramic and cone-beam computed tomographic images showed an irregular and exophytic bony mass on the anteromedial surface of the right mandibular condyle. A 3-phase bone scan revealed increased tracer uptake on the affected side. The lesion was treated with excision and reshaping under the diagnosis of osteochondroma confirmed by a histopathological examination. The lesion recurred after 3 years, and the patient underwent condylectomy. Mandibular condylar osteochondroma is often resected because it causes functional and aesthetic problems, but it rarely recurs. To the best of our knowledge, only 2 cases of recurrent osteochondromas of the mandibular condyle have been reported previously. Surgical treatment of the osteochondroma should be performed considering the possibility of recurrence, and long-term follow-up is recommended

Recurrent osteochondroma of the mandibular condyle: A case report

Energy Technology Data Exchange (ETDEWEB)

Kwon, Young Eun; Choi, Karp Shik; An, Chang Hyeon; Choi, So Young; An, Seo Young [School of Dentistry, Kyungpook National University, Daegu (Korea, Republic of); Lee, Jae Seo [Dept. of Oral and Maxillofacial Radiology, School of Dentistry, Chonnam National University, Gwangju (Korea, Republic of)

2017-03-15

A 21-year-old woman presented with facial asymmetry. Crepitus and clicking of the temporomandibular joint were noted. The midline deviated 5.5 mm to the left, and secondary malocclusion was observed. Panoramic and cone-beam computed tomographic images showed an irregular and exophytic bony mass on the anteromedial surface of the right mandibular condyle. A 3-phase bone scan revealed increased tracer uptake on the affected side. The lesion was treated with excision and reshaping under the diagnosis of osteochondroma confirmed by a histopathological examination. The lesion recurred after 3 years, and the patient underwent condylectomy. Mandibular condylar osteochondroma is often resected because it causes functional and aesthetic problems, but it rarely recurs. To the best of our knowledge, only 2 cases of recurrent osteochondromas of the mandibular condyle have been reported previously. Surgical treatment of the osteochondroma should be performed considering the possibility of recurrence, and long-term follow-up is recommended.

Expression of Bcl-2 in canine osteosarcoma

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F. Piro

2015-03-01

Full Text Available Osteosarcoma (OS is the most common primary malignancy of bone. It is responsible for 80-85% of the primary bone tumors affecting dogs and it is characterized by aggressive and invasive behavior, with a high metastatic potential. Several studies on cancer and related tumorigenesis, show an involvement of the mechanisms of programmed cell death and cell survival. Many signals seem to be involved in the related mechanism of autophagy and in particular, our interest is focused on the expression of a family of Bcl-2 that seems to be involved either in the control of biomolecular mechanisms like autophagy and apoptosis. In this study we investigated the expression of Bcl-2 in different cases of spontaneous canine osteosarcoma and the related preliminary results are described. We found Bcl-2 activity was increased in OS tissue compared to normal bone tissue. These results suggested that Bcl-2 activity may play an important role in the formation of OS and as a diagnostic for neoplastic activity. However, further research is needed to confirm the role of Bcl-2 activity in OS in canines.

Orthodontic management of a dilacerated central incisor and partially impacted canine with unilateral extraction - A case report.

Science.gov (United States)

Felicita, A Sumathi

2017-10-01

To align a dilacerated maxillary central incisor and partially impacted canine with unilateral extraction in a young patient with skeletal deep bite. A 14 year old male patient reported to the hospital with skeletal deep bite (basal plane angle-17°), severe horizontal pattern of growth (Go-Gn to Sn -22°), upright maxillary incisors (U1 to NA -26°) and retroclined lower incisors (L1 to NB -11°). The maxillary left central incisor was dilacerated, and the maxillary left canine was partially impacted. Unilateral extraction of the left maxillary premolar and left mandibular central incisor was done. A canine disimpaction spring was used to align the impacted canine. An anterior bite plane was given to open the bite. Superimposition of lateral cephalogram (T1, T2) revealed bite opening, normal overjet and overbite. There was backward rotation of the mandible and increase in lower anterior facial height. There was no evidence of root resorption or loss of vitality in the dilacerated tooth. Clinically the canine was well aligned in the arch. Orthodontic management of a dilacerated incisor can be done without root resorption or loss of vitality. The partially impacted canine was well aligned in the arch. Unilateral extraction can produce good treatment results.

A Comparative Study of Quantitative Assessment of Bone Mineral Density of Mandible

International Nuclear Information System (INIS)

Park, Won Kyl; Choi, Eui Hwan; Kim, Jae Duk

1999-01-01

This study was performed to compare the bone mineral densities measured at mandibular premolar area by copper-equivalent image and hydroxyapatite phantom with those measured at radius by dual energy absorptiometry and to evaluate the clinical usefulness of Digital system with slide scanner, copper-equivalent image, and hydroxyapatite phantom. For experiment, intraoral radiograms of 15 normal subjects ranged from 20 years old to 67 old were taken with copper-step wedge at mandibular premolar area and bone mineral densities calculated by conversion equation to bone mineral density of hydroxyapatite were compared with those measured at radius distal 1/3 area by Hologic QDR-1000. Obtained results as follows: 1) The conversion equation was Y=5.97X-0.25 and its determination coefficient was 0.9967. The coefficient of variation in the measurement of copper-equivalent value ranged from 4% to 8% and showed high reproducibility. 2) The coefficient of variation in the measurement of bone mineral density by the equation ranged from 7% to 8% and showed high reproducibility. 3) The bone mineral densities ranged from 0.35 to 0.79 g/cm 2 at mandibular premolar area. 4) The correlation coefficient between bone mineral densities at mandibular premolar area and those at radius distal 1/3 area was 0.8965. As summary, digital image analyzing system using copper-equivalent image and hydroxyapatite phantom appeared to be clinically useful to measure the bone mineral density at dental area.

Surgical treatment for mandibular osteoradionecrosis. Stepwise surgical treatment before wide resection

International Nuclear Information System (INIS)

Aoki, Shinjiro; Hirota, Makoto; Saito, Tomokatsu; Watanuki, Kei; Matsui, Yoshiro; Fujita, Kiyohide

2006-01-01

A method corresponding to the state of progress of necrosis is necessary for the treatment of mandibular osteoradionecrosis considering the healing conditions of the original focus. We devised a three-step treatment method that combined active application of platelet rich plasma (PRP) with particulate cancellous bone marrow (PCBM) with resolutive treatment using external skeletal fixation, as a step preceding wide segmental mandibulectomy and vascularized free combination flap graft when bone necrosis progressed. From January 2002 until December 2004, 14 patients (12 patients of oral cancer and 2 patients of mesopharygeal cancer) in whom mandibular osteoradionecrosis developed after radiation therapy, were treated. First step: when only alveolectomy is done, the wound is closed with a mucosal flap after PRP is applied to the bone surface as there is little sequestration. Second step: when sequestrectomy spreads to the central part of the mandible, PCBM is transplanted in addition to PRP, and the wound is closed by a local skin flap. Third step: when bone defect is segmental, any issue with soft tissue is first resolved and bone grafting is performed after that, while holding the remaining bone in position by using an external skeletal fixation device. A decrease in exposure of bone surface and alleviation of pain symptoms were achieved in all cases by treatment with the first step. However, outer cortical bone necrosis relapsed. The outcome of the second and third step treatment was good, and bone regeneration was achieved in 8 cases where PRP and transplantation of PCBM were done. Two cases suffered an infection, and curettage or retransplantation of PCBM was necessary. It is suggested that improvement of blood circulation and resolution of soft tissue are important for treatment of osteoradionecrosis. Therefore, waiting for resolution of the soft tissue using external skeletal fixation was effective, and PRP was useful in the healing process. (author)

Lingual nerve injury following surgical removal of mandibular third molar

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Abduljaleel Azad Samad

2017-12-01

Full Text Available Background and objective: The close proximity of lingual nerve in relation to the lingual cortical bone of the posterior mandibular third molar is clinically important because lingual nerve may be subjected to trauma during surgical removal of the impacted lower third molar. This prospective study aimed to evaluate the incidence of lingual nerve paresthesia following surgical removal of mandibular third molar in College of Dentistry, Hawler Medical University. Methods: A total of 116 third molars surgery were carried out under local anesthesia for 116 patients for removal of lower mandibular teeth Using Terence Ward's incision made in all cases, and after that, the buccal flap was reflected, lingual tissues had been retracted during bone removal with a periosteal elevator. The sensory disturbance was evaluated on the 7th postoperative day by standard questioning the patients: “Do you have any unusual feeling in your tongue, lingual gingiva and mucosa of the floor of the mouth?" Results: One patient experienced sensory disturbance, the lingual nerve paresthesia incidence was 0.9% as a transient sensory disturbance, while no patient of permanent sensory disturbance. Conclusion: The incidence of injury to the lingual nerve can be minimized by careful clinical evaluation, surgeon’s experience, surgical approach and knowledge about anatomical landmarks during surgical removal of an impacted lower third molar tooth.

Preservation and promotion of bone formation in the mandible as a response to a novel calcium-phosphate based biomaterial in mineral deficiency induced low bone mass male versus female rats

Science.gov (United States)

Srinivasan, Kritika; Naula, Diana P.; Mijares, Dindo Q.; Janal, Malvin N.; LeGeros, Raquel Z.; Zhang, Yu

2016-01-01

Calcium and other trace mineral supplements have previously demonstrated to safely improve bone quality. We hypothesize that our novel calcium-phosphate based biomaterial (SBM) preserves and promotes mandibular bone formation in male and female rats on mineral deficient diet (MD). Sixty Sprague-Dawley rats were randomly assigned to receive one of three diets (n = 10): basic diet (BD), MD or mineral deficient diet with 2% SBM. Rats were sacrificed after 6 months. Micro-Computed Tomography (μCT) was used to evaluate bone volume and 3D-microarchitecture while microradiography (Faxitron) was used to measure bone mineral density from different sections of the mandible. Results showed that bone quality varied with region, gender and diet. MD reduced bone mineral density (BMD) and volume and increased porosity. SBM preserved BMD and bone mineral content (BMC) in the alveolar bone and condyle in both genders. In the alveolar crest and mandibular body, while preserving more bone in males, SBM also significantly supplemented female bone. Results indicate that mineral deficiency leads to low bone mass in skeletally immature rats, comparatively more in males. Furthermore, SBM administered as a dietary supplement was effective in preventing mandibular bone loss in all subjects. This study suggests that the SBM preparation has potential use in minimizing low peak bone mass induced by mineral deficiency and related bone loss irrespective of gender. PMID:26914814

SYNOVIAL CHONDROMATOSIS OF THE TEMPORO-MANDIBULAR JOINT. A CASE REPORT

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V. MALANCHUK

2015-09-01

Full Text Available The study describes a rare clinical case of synovial chondromatosis of the temporo-mandibular joint, in a 53 year-old patient. In the prehospital stage, the patient was examined by additional diagnostic methods – 3D CT and subsequent computer simulation, in view of subsequent surgery. In January 2015, partial synovektomy of the right temporo-mandibular joint with removal of cartilaginous impurities was performed under general anesthesia. After histopathological confirmation of the clinical diagnosis, the patient was discharged in satisfactory condition, with recommendations for further examination and radiological control. Synovial chondromatosis of the temporo-mandibular joint is a disease characterized by impaired formation of cartilage or of intraarticular, cartilaginous, and relatively rare bone impurities. An important role in the diagnosis of joints’ synovial chondromatosis is played by the instrumental research methods, especially X-ray. Surgical treatment is recommended as a function of the prevalence of lesions.

Autotransplantation of Mandibular Third Molar with Buccal Cortical Plate to Replace Vertically Fractured Mandibular Second Molar: A Novel Technique.

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Zufía, Juan; Abella, Francesc; Trebol, Ivan; Gómez-Meda, Ramón

2017-09-01

Tooth replacement often leads to inadequate vertical volume in the recipient site bone when a tooth has been extracted because of a vertical root fracture (VRF). This case report presents the autotransplantation of a mandibular third molar (tooth #32) with the attached buccal cortical plate to replace a mandibular second molar (tooth #31) diagnosed with a VRF. After extraction of tooth #31, the recipient socket was prepared based on the size measured in advance with cone-beam computed tomographic imaging. The precise and calculated osteotomy of the cortical bone of tooth #32 allowed for the exact placement of the donor tooth in the position of tooth #31. The total extraoral time was only 25 minutes. The block was fixed to the recipient socket with an osteosynthesis screw and splinted with a double resin wire for 8 weeks. At the 6-month follow-up, the screw was removed, and the stability of the tooth and the regeneration obtained throughout the vestibular area were confirmed. At the 2-year follow-up, the transplanted tooth was asymptomatic and maintained a normal bone level. Advantages of autotransplantation over dental implants include maintenance of proprioception, possible orthodontic movements, and a relatively low cost. This case report demonstrates that an autotransplantation of a third molar attached to its buccal cortical plate is a viable option to replace teeth with a VRF. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Micro-computed tomography (CT) based assessment of dental regenerative therapy in the canine mandible model

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Khobragade, P.; Jain, A.; Setlur Nagesh, S. V.; Andreana, S.; Dziak, R.; Sunkara, S. K.; Sunkara, S.; Bednarek, D. R.; Rudin, S.; Ionita, C. N.

2015-03-01

High-resolution 3D bone-tissue structure measurements may provide information critical to the understanding of the bone regeneration processes and to the bone strength assessment. Tissue engineering studies rely on such nondestructive measurements to monitor bone graft regeneration area. In this study, we measured bone yield, fractal dimension and trabecular thickness through micro-CT slices for different grafts and controls. Eight canines underwent surgery to remove a bone volume (defect) in the canine's jaw at a total of 44 different locations. We kept 11 defects empty for control and filled the remaining ones with three regenerative materials; NanoGen (NG), a FDA-approved material (n=11), a novel NanoCalcium Sulfate (NCS) material (n=11) and NCS alginate (NCS+alg) material (n=11). After a minimum of four and eight weeks, the canines were sacrificed and the jaw samples were extracted. We used a custombuilt micro-CT system to acquire the data volume and developed software to measure the bone yield, fractal dimension and trabecular thickness. The software used a segmentation algorithm based on histograms derived from volumes of interest indicated by the operator. Using bone yield and fractal dimension as indices we are able to differentiate between the control and regenerative material (p<0.005). Regenerative material NCS showed an average 63.15% bone yield improvement over the control sample, NCS+alg showed 55.55% and NanoGen showed 37.5%. The bone regeneration process and quality of bone were dependent upon the position of defect and time period of healing. This study presents one of the first quantitative comparisons using non-destructive Micro-CT analysis for bone regenerative material in a large animal with a critical defect model. Our results indicate that Micro-CT measurement could be used to monitor invivo bone regeneration studies for greater regenerative process understanding.

Use of a centrifugation-based, point-of-care device for production of canine autologous bone marrow and platelet concentrates.

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Thoesen, Michael S; Berg-Foels, Wendy S Vanden; Stokol, Tracy; Rassnick, Kenneth M; Jacobson, May S; Kevy, Sherwin V; Todhunter, Rory J

2006-10-01

To analyze a centrifugation-based, point-of-care device that concentrates canine platelets and bone marrow-derived cells. 19 adult sexually intact dogs. Anticoagulated peripheral blood (60 mL) and 60 mL of anticoagulated bone marrow aspirate (BMA) were concentrated by centrifugation with the centrifugation-based, point-of-care device to form a platelet and a bone marrow concentrate (BMC) from 11 dogs. Blood samples were analyzed on the basis of hemograms, platelet count, and PCV. The BMA and BMC were analyzed to determine PCV, total nucleated cell count, RBC count, and differential cell counts. The BMC stromal cells were cultured in an osteoinductive medium. Eight additional dogs were used to compare the BMC yield with that in which heparin was infused into the bone marrow before aspiration. The centrifugation-based, point-of-care device concentrated platelets by 6-fold over baseline (median recovery, 63.1%) with a median of 1,336 x 10(3) platelets/microL in the 7-mL concentrate. The nucleated cells in BMCs increased 7-fold (median recovery, 42.9%) with a median of 720 x 10(3) cells/microL in the 4-mL concentrate. The myeloid nucleated cells and mononuclear cells increased significantly in BMCs with a significant decrease in PCV, compared with that of BMAs. Stromal cell cultures expressed an osteoblastic phenotype in culture. Infusion of heparin into the bone marrow eliminated clot formation and created less variation in the yield (median recovery, 61.9%). Bone marrow-derived cell and platelet-rich concentrates may form bone if delivered in an engineered graft, thus decreasing the need for cancellous bone grafts.

Patient-specific reconstruction plates are the missing link in computer-assisted mandibular reconstruction: A showcase for technical description.

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Cornelius, Carl-Peter; Smolka, Wenko; Giessler, Goetz A; Wilde, Frank; Probst, Florian A

2015-06-01

Preoperative planning of mandibular reconstruction has moved from mechanical simulation by dental model casts or stereolithographic models into an almost completely virtual environment. CAD/CAM applications allow a high level of accuracy by providing a custom template-assisted contouring approach for bone flaps. However, the clinical accuracy of CAD reconstruction is limited by the use of prebent reconstruction plates, an analogue step in an otherwise digital workstream. In this paper the integration of computerized, numerically-controlled (CNC) milled, patient-specific mandibular plates (PSMP) within the virtual workflow of computer-assisted mandibular free fibula flap reconstruction is illustrated in a clinical case. Intraoperatively, the bone segments as well as the plate arms showed a very good fit. Postoperative CT imaging demonstrated close approximation of the PSMP and fibular segments, and good alignment of native mandible and fibular segments and intersegmentally. Over a follow-up period of 12 months, there was an uneventful course of healing with good bony consolidation. The virtual design and automated fabrication of patient-specific mandibular reconstruction plates provide the missing link in the virtual workflow of computer-assisted mandibular free fibula flap reconstruction. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

The Effects of Orthodontic Forces during Canine Retraction Using Self-ligating Brackets on Gingival Crevicular Fluid Enzyme Activity, Canine Movement and Root Resorption

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Rohaya Megat Abdul Wahab; Albira Sintian; Zaidah Zainal Arifin; Zaidah Zainal Ariffin; Shahrul Hisham Zainal Ariffin

2015-01-01

Alkaline phosphatase (ALP), tartrate-resistant acid phosphatase (TRAP) and aspartate aminotransferase (AST) activities were studied as bio markers of canine movement. Root resorption was also evaluated in canines subjected to the orthodontic forces. Nineteen subjects randomly received 100 and 150 g force using self-ligating brackets (SLB) either on the right or left site of maxillary arch. Gingival crevicular fluid samples were collected at distal sites of canines for five consecutive weeks. The activities of ALP, TRAP and AST were assayed and measured spectrophotometrically. Canine movement was measured for five consecutive weeks while root resorption was monitored at baseline, week 0 and week 5 using periapical radiographs. In 100 g group, TRAP activity significantly increased in week 3-5 when compared to TRAP baseline activity. However, ALP and AST activities slightly increased. In 150 g group, ALP and TRAP activities slightly increased when compared with their baseline activities. However, AST significantly increased in week 5. Canine movement and root resorption were not significantly different (p<0.05) in both groups. A force of 100 and 150 g slightly increased the bone modeling process and resulted in similar canine movement and root resorption. Therefore, 100 g force could be an optimum force for canine retraction and is preferable (compared with 150 g force) in canine retraction using SLB. (author)

An unusual case of ameloblastoma observed in the left anterior mandible.

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Canger, Emin Murat; Çelenk, Peruze; Bulut, Emel; Günhan, Ömer

2014-11-01

To report a small intaalveolar ameloblastoma which resembled cystic lesion, and to emphasize the value of Computed tomography (CT) in radiographic examination. Ameloblastoma is a slow-growing, locally invasive odontogenic neoplasm that accounts for approximately 10% of all tumors detected in the jaws. Radiographically, those tumors are usually well-defined. Computerized tomography is highly recommended to confirm the diagnosis. A 48-year-old female attended with a chief complaint of painless swelling in the left anterior of mandible, 1 month duration. In intraoral examination, non-fluctuant, immobile, approximately 1 × 1 cm in dimension, painless, swelling which had a bone-like hardness and located in the mandibular canine region was detected. Panoramic radiography revealed a well circumscribed unilocular radiolucent lesion located in the inter-radicular area of left mandibular lateral and canine teeth. In CT examination it was realized that the lesion was multilocular. Histopathological examination of the biopsy specimen was reported as ameloblastoma. It is extremely difficult to find such an ameloblastoma in small dimension in alvolar bone.

Contemporary Management of Mandibular Fracture Nonunion-A Retrospective Review and Treatment Algorithm.

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Ostrander, Benjamin T; Wang, Howard D; Cusano, Alessandro; Manson, Paul N; Nam, Arthur J; Dorafshar, Amir H

2018-02-06

Nonunion is an uncommon complication after mandibular fractures. The purpose of this investigation was to compare outcomes of patients with mandibular fracture nonunion who were treated with a 1- versus 2-stage approach and propose a pragmatic treatment algorithm for surgical management based on preoperative characteristics. The authors conducted a retrospective study consisting of patients who presented to 2 level 1 trauma centers for the management of mandibular fracture nonunion over a 10-year period. The primary predictor variable was 1- versus 2-stage treatment. Outcomes were examined to propose a treatment algorithm. Eighteen patients were included in the study. The sample's mean age was 44.0 ± 19.3 years and most were men (88.9%). Mandibular angle and body accounted for 77.8% of cases. A single-stage approach was used in 13 patients (72.2%). Bone grafts or vascularized bone flaps were required in 13 patients (72.2%). Patients who required 2-stage treatments had intraoral soft tissue defects. Mean length of follow-up was 13.3 ± 20.4 months. All patients achieved bony union, with complications occurring in 5 patients (27.8%). The authors' 10-year experience was used to formulate a treatment algorithm based on bony defect size and soft tissue status, which can be used to inform optimal surgical management. Nonunion of mandibular fractures is an infrequent and complex condition requiring careful and deliberate surgical management. A single-stage approach is appropriate in most cases and does not negatively affect outcomes. Bony defect size and soft tissue status are essential parameters for determining the approach and timing of reconstruction. Copyright © 2018 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Forced extrusion for removal of impacted third molars close to the mandibular canal Extrusión forzada para extraer los terceros molares impactados cerca del canal mandibular

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Dennis Flanagan DDS

2012-03-01

Full Text Available Impacted mandibular third molars can be located in close proximity to the mandibular canal. This creates a risk for the nerve or artery injury. These are contained in the canal. However, the impacted third molar can be moved coronally by orthodontic means, after removal of overlying bone, and safely extracted. The orthodontic intervention slowly moves the tooth apex away from the mandibular canal and reduces the potential for a neural injury. This method may be useful for older patients with root apices that approximate or are actually located in the mandibular canal. This technique needs further study. There is a theoretical potential for neural or arterial injury from physical contact of the tooth apex as it moves by or through the mandibular canal.Los terceros molares inferiores impactados pueden localizarse muy cerca del canal mandibular. Esto constituye un riesgo de lesión del nervio o la arteria, que se localizan dentro del canal. No obstante, el tercer molar impactado puede desplazarse en dirección coronal con ortodoncia, tras ostectomía del hueso suprayacente, y extraerse sin riesgos. La intervención ortodóncica desplaza lentamente el ápice del diente fuera del canal mandibular y reduce la posibilidad de lesión neural. Este método puede ser útil para pacientes de edad avanzada con ápices dentales que se aproximan o en realidad se localizan en el canal mandibular. La técnica necesita un estudio adicional. Hay la posibilidad teórica de lesión neural o arterial a partir del contacto físico del ápice del diente a medida que se desplaza a través del canal mandibular.

In vitro evaluation of three different biomaterials as scaffolds for canine mesenchymal stem cells

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Oduvaldo Câmara Marques Pereira-Junior

2013-05-01

Full Text Available PURPOSE: To evaluate in vitro ability the of three different biomaterials - purified hydroxyapatite, demineralized bone matrix and castor oil-based polyurethane - as biocompatible 3D scaffolds for canine bone marrow mesenchymal stem cell (MSC intending bone tissue engineering. METHODS: MSCs were isolated from canine bone marrow, characterized and cultivated for seven days with the biomaterials. Cell proliferation and adhesion to the biomaterial surface were evaluated by scanning electron microscopy while differentiation into osteogenic lineage was evaluated by Alizarin Red staining and Sp7/Osterix surface antibody marker. RESULTS: The biomaterials allowed cellular growth, attachment and proliferation. Osteogenic differentiation occurred in the presence of hydroxyapatite, and matrix deposition commenced in the presence of the castor oil-based polyurethane. CONCLUSION: All the tested biomaterials may be used as mesenchymal stem cell scaffolds in cell-based orthopedic reconstructive therapy.

A comparative study of the effect of Bio-Oss® in combination with concentrated growth factors or bone marrow-derived mesenchymal stem cells in canine sinus grafting.

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Wang, Fang; Li, Qiong; Wang, Zuolin

2017-08-01

To compare the effects of Bio-Oss ® in combination with concentrated growth factors (CGFs) and bone marrow-derived mesenchymal stem cells (BMSCs) on bone regeneration for maxillary sinus floor augmentation in beagle dogs. Six beagle dogs received bilateral maxillary sinus floor augmentation. Venous blood drawn from dogs was collected and centrifuged to obtain CGFs. BMSCs derived from canine bone marrow were cultured using density gradient centrifugation. The suspension of BMSCs was added onto Bio-Oss ® granules at a density of 2 × 10 6 cells/ml, and the BMSCs/Bio-Oss ® constructs were incubated for an additional 4 h before use. Twelve sinuses were grafted with a mixture of CGFs/Bio-Oss ® , BMSCs/Bio-Oss ® construct, or Bio-Oss ® alone. Six months later, the bone formation of bilateral sinuses was evaluated by Micro-CT, microhardness test, histological examination, and histomorphometry. No adverse effect was found in these dogs. The dome-shaped augmentation protruded into the sinus cavity. Micro-CT revealed that there was significant difference in BV/TV but not in Tb. N, between groups A, B, and C. The extent of microhardness in groups A and B was significantly higher than in group C. The proportion of newly formed bone in groups A and B showed significant difference when compared to group C (P ≤ 0.01). The amount of residual grafts in groups A and B was significantly lower than in group C. Grafting with Bio-Oss ® in combination with CGFs can increase new bone formation more efficiently than using Bio-Oss ® alone in a canine model. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Prediction of width of un-erupted incisors, canines and premolars in a Ugandan population: A cross sectional study

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Buwembo William

2012-07-01

Full Text Available Abstract Background Accurate prediction of the space forms an important part of an orthodontic assessment in the mixed dentition. However the most commonly used methods of space analysis are based on data developed on Caucasian populations. In order to provide more accurate local data we set out to develop a formula for predicting the widths of un-erupted canines and premolars for a Ugandan population and to compare the predicted widths of the teeth from this formula with those obtained from Moyers’ tables, and Tanaka and Johnston’s equations. Methods Dental casts were prepared using mandibular and maxillary arch impressions of 220 children (85 boys/135 girls aged 12–17 years recruited from schools in Kampala, Uganda. The mesio-distal width of the mandibular incisors, mandibular and maxillary canines and premolars were measured with a pair of digital calipers. Based on regression analysis, predictive equations were derived and the findings were compared with those presented in Moyers’ probability tables, and Tanaka and Johnston’s equations. Results There were no statistically significant differences between the tooth widths predicted by our equations and those from Moyers’ probability tables at the 65th and 75th percentile probabilities for the girls and at 75th level in boys in the mandibular arch. While in the maxillary arch no statistically significant differences at the 75th and 95th levels were noted in girls. There were statistically significant differences between predicted tooth sizes using equations from the present study and those predicted from the Tanaka and Johnston regression equations. Conclusions In this Ugandan population, Moyers’ probability tables could be used to predict tooth widths at specific percentile probabilities, but generally, Tanaka and Johnston technique tends to overestimate the tooth widths.

Radiolabeled microsphere measurements of alveolar bone blood flow in dogs

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Kaplan, M.L.; Jeffcoat, M.K.; Goldhaber, P.

1978-01-01

Radiolabeled microspheres were injected into the left cardiac ventricle in healthy adult dogs to quantify blood in maxillary and mandibular alveolar bone. Heart rate, arterial blood pressure and pulse contour were monitored throughout each experiment. Blood flow in maxillary alveolar bone was more than 30 % greater (p<.001) than in mandibular alveolar bone. Alveolar bone blood flow (mean +- S.D.) measured as ml/min per gram was 0.12 +- .02 in the maxilla compared to 0.09 +- .02 in the mandible. The cardiovascular parameters monitored were constant immediately prior to the injection of microspheres and remained unchanged during and following injection. It is possible that radiolabeled microspheres can be used to quantify the circulatory changes in alveolar bone during the development of destructive periodontal disease in dogs. (author)

Orthodontic Extraction of High-Risk Impacted Mandibular Third Molars in Close Proximity to the Mandibular Canal: A Systematic Review.

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Kalantar Motamedi, Mahmood Reza; Heidarpour, Majid; Siadat, Sara; Kalantar Motamedi, Alimohammad; Bahreman, Ali Akbar

2015-09-01

Extraction of mandibular third molars (M3s) in close proximity to the mandibular canal has some inherent risks to adjacent structures, such as neurologic damage to teeth, bone defects distal to the mandibular second molar (M2), or pathologic fractures in association with enlarged dentigerous cysts. The procedure for extrusion and subsequent extraction of high-risk M3s is called orthodontic extraction. This is a systematic review of the available approaches for orthodontic extraction of impacted mandibular M3s in close proximity to the mandibular canal and their outcomes. The PubMed, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), DOAJ, Google Scholar, OpenGrey, Iranian Science Information Database (SID), Iranmedex, and Irandoc databases were searched using specific keywords up to June 2, 2014. Studies were evaluated based on predetermined eligibility criteria, treatment approaches, and their outcomes. Thirteen articles met the inclusion criteria. A total of 123 impacted teeth were extracted by orthodontic extraction and 2 cases were complicated by transient paresthesia. Three types of biomechanical approaches were used: 1) using the posterior maxillary region as the anchor for orthodontic extrusion of lower M3s, 2) simple cantilever springs attached to the M3 buttonhole, and 3) cantilever springs tied to a bonded orthodontic bracket on the M3 plus multiple-loop spring wire for distal movement of the M3. Osteo-periodontal status of M2s also improved uneventfully. Despite the drawbacks of orthodontic extraction, removal of deeply impacted M3s using the described techniques is safe with regard to mandibular nerve injury and neurologic damage. Orthodontic extraction is recommended for extraction of impacted M3s that present a high risk of postoperative osteo-periodontal defects on the distal surface of the adjacent M2 and those associated with dentigerous cysts. Copyright © 2015 American Association of Oral and Maxillofacial Surgeons. Published by

Locating Mandibular Foramen in Children with Mandibular Retrognathism in Mixed Dentition

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Mehrsa Paryab

2015-06-01

Full Text Available Background and aims. One of the most common reasons forthe inferior alveolar nerve block anesthesia failure is the variation in mandibular foramen location. The aim of this study was to assess the location of mandibular foramen in chil-dren with mandibular retrognathism in comparison to children with normal skeletal occlusion in the mixed dentition. Materials and methods. One hundred and twenty panoramic radiographs of patients in mixed dentition period, undergo-ing orthodontic treatment, were selected based on inclusion criteria, skeletal occlusion and stage of dental development. The radiographs were divided into two groups: I: 60 panoramic radiographs of patients with normal skeletal occlusion (15 in each of the Hellman dental age stages; II: 60 panoramic radiographs of patients with mandibular retrognathism (15 in each of the Hellman dental age stages. The radiographs were traced and the linear distance from the mandibular foramen to the borders of the mandibular ramus and its angular position were identified. The measurements were compared between the two groups and among the four dental age groups by t-test, ANOVA and post hoc tests. Results. No statistically significant differences werefound between the patients with normal skeletal occlusion and patients with mandibular retrognathism (P>0.05. Statistical tests showed significant differences in the vertical location of mandibu-lar foramen and gonial angle between the four dental age groups (P<0.05. Conclusion. Mandibular retrognathism does not have a significant impact on the location of the mandibular foramen in the mixed dentition period. The child’s dental age would be considered in the localization of the mandibular foramen.

A role for subchondral bone changes in the process of osteoarthritis; a micro-CT study of two canine models.

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Sniekers, Yvonne H; Intema, Femke; Lafeber, Floris P J G; van Osch, Gerjo J V M; van Leeuwen, Johannes P T M; Weinans, Harrie; Mastbergen, Simon C

2008-02-12

This study evaluates changes in peri-articular bone in two canine models for osteoarthritis: the groove model and the anterior cruciate ligament transection (ACLT) model. Evaluation was performed at 10 and 20 weeks post-surgery and in addition a 3-weeks time point was studied for the groove model. Cartilage was analysed, and architecture of the subchondral plate and trabecular bone of epiphyses was quantified using micro-CT. At 10 and 20 weeks cartilage histology and biochemistry demonstrated characteristic features of osteoarthritis in both models (very mild changes at 3 weeks). The groove model presented osteophytes only at 20 weeks, whereas the ACLT model showed osteophytes already at 10 weeks. Trabecular bone changes in the groove model were small and not consistent. This contrasts the ACLT model in which bone volume fraction was clearly reduced at 10 and 20 weeks (15-20%). However, changes in metaphyseal bone indicate unloading in the ACLT model, not in the groove model. For both models the subchondral plate thickness was strongly reduced (25-40%) and plate porosity was strongly increased (25-85%) at all time points studied. These findings show differential regulation of subchondral trabecular bone in the groove and ACLT model, with mild changes in the groove model and more severe changes in the ACLT model. In the ACLT model, part of these changes may be explained by unloading of the treated leg. In contrast, subchondral plate thinning and increased porosity were very consistent in both models, independent of loading conditions, indicating that this thinning is an early response in the osteoarthritis process.

Morphological study of maxillary canine region based on CT

International Nuclear Information System (INIS)

Yamada, Maiko; Takamori, Hitoshi; Ide, Yoshiaki; Yosue, Takashi

2010-01-01

The maxilla is generally known as a site where anatomical limitations make it difficult to obtain sufficient bone volume. A large amount of bone exists in the canine region between the anterior margin of the maxillary sinus and the piriform aperture margin. Although this region is crucial for implant treatments, there have not been any reports on morphological studies of the region. In this study, we investigated the morphology of the canine region based on CT, and also the morphology and position of the maxillary sinus located posterior to the canine region. The results were as follows: In the area above the anterior nasal spine, the higher the level, the smaller the mesio-distal length and the bucco-lingual width tended to become. In the area above the anterior nasal spine, the mesio-distal length and the bucco-lingual width tended to be smaller in female patients than in male patients. In the area above the anterior nasal spine, no significant differences in mesio-distal length and bucco-lingual width were observed between dentulous and edentulous jaws. The morphology of the maxillary sinus was mainly of an inverse-trapezoidal, circular, or triangular form. The position of the anterior wall of the maxillary sinus was most frequently found at the site corresponding to the second premolar. Through this study, we have reconfirmed that the canine region is vital for implant treatments in the maxilla. (author)

Assessment of radiographic factors affecting surgical exposure and orthodontic alignment of impacted canines of the palate: a 15-year retrospective study.

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Motamedi, Mohammad Hosein Kalantar; Tabatabaie, Fataneh Alavi; Navi, Fina; Shafeie, Hasan Ali; Fard, Behnam Khosravani; Hayati, Zahra

2009-06-01

Impacted canines require a combination of both surgical and orthodontic management. In this study, patients treated for bone-impacted canines of the hard palatal were evaluated to assess which radiographic factors influenced the feasibility to move impacted maxillary permanent canines from the hard palate into the alveolar arch. Eighty patients aged 12 to 24 (average 16 years) were treated surgically and orthodontically to align 146 bone-impacted canines of the hard palate (from 1994 to 2008). Factors such as age, sex, angulation of the canine to the midline (CAM), anomaly of the canine root (RA), overlap of the adjacent lateral incisor root (OALIR), and ratio of root formation (RRF) upon treatment were documented. Radiographic records and demographic data were assessed. The following radiographic measurements of canine position were made from the orthopantomogram (OPG): (1) angulation to the midline, (2) anteroposterior position of the root, (3) overlap of the adjacent incisor. RA or dilaceration was assessed from the OPG, maxillary occlusal (MO), and periapical (PA) radiographs. Whether the impacted canine had responded to surgical exposure and was orthodontically aligned, or surgically removed and discarded was also recorded. The data were analyzed to assess and correlate significance. Eighty patients aged 12 to 24 (19 males and 61 females) with 146 bone-impacted permanent canines of the hard palatal were treated. One hundred and three teeth (70.54%) had responded to surgical exposure and orthodontic alignment within 9 to 12 months. Forty-three impacted canine teeth (29.46%) had to be surgically removed because of ankylosis and no movement after 8 to 9 months using 50 to 60 g of traction force via elastic chains. Data analysis via chi-square and Pearson correlation tests showed that as the CAM increased (> 45 degrees), the canine was more likely to be unresponsive to treatment (P half the root) of the adjacent lateral incisor root (OALIR) via the canine crown

Radiologic study of mandibular foramen of mandibular prognathism by three-dimensional computed tomography

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Lee, Seung Hun; Moon, Cheol Hyun; Im, Jeong Soo; Seo, Hwa Jeong [Graduate School of Public Health and Social Welfare, Gachon University of Medicine and Science, Incheon (Korea, Republic of)

2010-06-15

This study is aimed to evaluate the position of mandibular foramen of mandibular prognathism patients using 3-dimensional CT images in order to reduce the chance of an anesthetic failure of the mandibular nerve and to prevent the damage to the inferior alveolar nerve during the orthognathic surgery. The control group consist of 30 patients with class I occlusion. The experimental group consist of 44 patients with class III malocclusion. Three-dimensional computed tomography was used to evaluate the position of the mandibular foramina. The distance between mandibular plane and mandibular foramen, class I was 25.385 mm, class III was 23.628 mm. About the distance between occlusal plane and mandibular foramen, class I was 1.478 mm, class III was 5.144 mm. The distance between posterior border plan of mandibular ramus and mandibular foramen had not statistically significant. About the distance between sagittal plane of mandible and mandibular foramen did not also showed statistically significant. The result of this study could help the clinicians to apprehend more accurate anatomical locations of the foramina on the mandible with various facial skeletal types. Thereby to perform more accurate block anesthesia of the mandibular nerve and osteotomy with minimal nerve damage. In addition, this study could provide fundamental data for any related researches about the location of the mandibular foramina for other purposes.

Radiologic study of mandibular foramen of mandibular prognathism by three-dimensional computed tomography

International Nuclear Information System (INIS)

Lee, Seung Hun; Moon, Cheol Hyun; Im, Jeong Soo; Seo, Hwa Jeong

2010-01-01

This study is aimed to evaluate the position of mandibular foramen of mandibular prognathism patients using 3-dimensional CT images in order to reduce the chance of an anesthetic failure of the mandibular nerve and to prevent the damage to the inferior alveolar nerve during the orthognathic surgery. The control group consist of 30 patients with class I occlusion. The experimental group consist of 44 patients with class III malocclusion. Three-dimensional computed tomography was used to evaluate the position of the mandibular foramina. The distance between mandibular plane and mandibular foramen, class I was 25.385 mm, class III was 23.628 mm. About the distance between occlusal plane and mandibular foramen, class I was 1.478 mm, class III was 5.144 mm. The distance between posterior border plan of mandibular ramus and mandibular foramen had not statistically significant. About the distance between sagittal plane of mandible and mandibular foramen did not also showed statistically significant. The result of this study could help the clinicians to apprehend more accurate anatomical locations of the foramina on the mandible with various facial skeletal types. Thereby to perform more accurate block anesthesia of the mandibular nerve and osteotomy with minimal nerve damage. In addition, this study could provide fundamental data for any related researches about the location of the mandibular foramina for other purposes.

Combined orthognathic distraction procedure: Le Fort I maxillary osteotomy and mandibular curvilinear distraction osteogenesis. A new technique for craniofacial management.

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Schendel, Stephen A; Hazan-Molina, Hagai; Aizenbud, Dror

2014-04-01

Dentofacial deformities are traditionally treated by maxillary and mandibular osteotomies conducted separately or simultaneously. Recently, distraction osteogenesis has become an irreplaceable part of the surgical armamentarium, for its ability to induce new bone formation between the surfaces of bone segments that are gradually separated by incremental traction, along with a simultaneous expansion of the surrounding soft-tissue envelope. The aim of this article is to describe a combined surgical technique consisting of simultaneous maxillary Le Fort I advancement and mandibular surgical repositioning by means of bilateral sagittal split osteotomy with a curvilinear distractor based on a preliminary computerized presurgical prediction.

Mandibular reconstruction with composite microvascular tissue transfer

International Nuclear Information System (INIS)

Coleman, J.J. III; Wooden, W.A.

1990-01-01

Microvascular free tissue transfer has provided a variety of methods of restoring vascularized bone and soft tissue to difficult defects created by tumor resection and trauma. Over 7 years, 26 patients have undergone 28 free flaps for mandibular reconstruction, 15 for primary squamous cell carcinoma of the floor of the mouth or tongue, 7 for recurrent tumor, and 6 for other reasons [lymphangioma (1), infection (1), gunshot wound (1), and osteoradionecrosis (3)]. Primary reconstruction was performed in 19 cases and secondary in 9. All repairs were composite flaps including 12 scapula, 5 radial forearm, 3 fibula, 2 serratus, and 6 deep circumflex iliac artery. Mandibular defects included the symphysis alone (7), symphysis and body (5), symphysis-body-ramus condyle (2), body or ramus (13), and bilateral body (1). Fourteen patients had received prior radiotherapy to adjuvant or curative doses. Eight received postoperative radiotherapy. All patients had initially successful vascularized reconstruction by clinical examination (28) and positive radionuclide scan (22 of 22). Bony stability was achieved in 25 of 26 patients and oral continence in 24 of 26. One complete flap loss occurred at 14 days. Complications of some degree developed in 22 patients including partial skin necrosis (3), orocutaneous fistula (3), plate exposure (1), donor site infection (3), fracture of reconstruction (1), and fracture of the radius (1). Microvascular transfer of bone and soft tissue allows a reliable reconstruction--despite previous radiotherapy, infection, foreign body, or surgery--in almost every situation in which mandible and soft tissue are absent. Bony union, a healed wound, and reasonable function and appearance are likely despite early fistula, skin loss, or metal plate or bone exposure

Mandibular reconstruction with composite microvascular tissue transfer

Energy Technology Data Exchange (ETDEWEB)

Coleman, J.J. III; Wooden, W.A. (Emory Univ. School of Medicine, Atlanta, GA (USA))

1990-10-01

Microvascular free tissue transfer has provided a variety of methods of restoring vascularized bone and soft tissue to difficult defects created by tumor resection and trauma. Over 7 years, 26 patients have undergone 28 free flaps for mandibular reconstruction, 15 for primary squamous cell carcinoma of the floor of the mouth or tongue, 7 for recurrent tumor, and 6 for other reasons (lymphangioma (1), infection (1), gunshot wound (1), and osteoradionecrosis (3)). Primary reconstruction was performed in 19 cases and secondary in 9. All repairs were composite flaps including 12 scapula, 5 radial forearm, 3 fibula, 2 serratus, and 6 deep circumflex iliac artery. Mandibular defects included the symphysis alone (7), symphysis and body (5), symphysis-body-ramus condyle (2), body or ramus (13), and bilateral body (1). Fourteen patients had received prior radiotherapy to adjuvant or curative doses. Eight received postoperative radiotherapy. All patients had initially successful vascularized reconstruction by clinical examination (28) and positive radionuclide scan (22 of 22). Bony stability was achieved in 25 of 26 patients and oral continence in 24 of 26. One complete flap loss occurred at 14 days. Complications of some degree developed in 22 patients including partial skin necrosis (3), orocutaneous fistula (3), plate exposure (1), donor site infection (3), fracture of reconstruction (1), and fracture of the radius (1). Microvascular transfer of bone and soft tissue allows a reliable reconstruction--despite previous radiotherapy, infection, foreign body, or surgery--in almost every situation in which mandible and soft tissue are absent. Bony union, a healed wound, and reasonable function and appearance are likely despite early fistula, skin loss, or metal plate or bone exposure.

Computer Simulation Surgery for Mandibular Reconstruction Using a Fibular Osteotomy Guide

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Woo Shik Jeong

2014-09-01

Full Text Available In the present study, a fibular osteotomy guide based on a computer simulation was applied to a patient who had undergone mandibular segmental ostectomy due to oncological complications. This patient was a 68-year-old woman who presented to our department with a biopsy-proven squamous cell carcinoma on her left gingival area. This lesion had destroyed the cortical bony structure, and the patient showed attenuation of her soft tissue along the inferior alveolar nerve, indicating perineural spread of the tumor. Prior to surgery, a three-dimensional computed tomography scan of the facial and fibular bones was performed. We then created a virtual computer simulation of the mandibular segmental defect through which we segmented the fibular to reconstruct the proper angulation in the original mandible. Approximately 2-cm segments were created on the basis of this simulation and applied to the virtually simulated mandibular segmental defect. Thus, we obtained a virtual model of the ideal mandibular reconstruction for this patient with a fibular free flap. We could then use this computer simulation for the subsequent surgery and minimize the bony gaps between the multiple fibular bony segments.

Association between absolute tumor burden and serum bone-specific alkaline phosphatase in canine appendicular osteosarcoma.

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Sternberg, R A; Pondenis, H C; Yang, X; Mitchell, M A; O'Brien, R T; Garrett, L D; Helferich, W G; Hoffmann, W E; Fan, T M

2013-01-01

In dogs with appendicular osteosarcoma (OSA), increased pretreatment serum bone-specific alkaline phosphatase (BALP) activity is a negative prognostic factor, associated with shorter disease-free intervals and survival times, but a biologic basis for observed differential serum BALP activities in canine OSA patients remains incompletely defined. Serum BALP activity will correlate with absolute tumor burden in dogs with OSA. This study included 96 client-owned dogs with appendicular OSA. In canine OSA cell lines, the expression and membranous release of BALP was evaluated in vitro. The correlation between serum BALP activity and radiographic primary tumor size was evaluated in OSA-bearing dogs. In dogs developing visceral OSA metastases, serial changes in serum BALP activities were evaluated in relation to progression of macroscopic metastases, and visceral metastatic OSA cells were evaluated for BALP expression. In vitro, BALP expression was not associated with either tumorigenic or metastatic phenotype, rather the quantity of membranous BALP released was proportional with cell density. In dogs devoid of macroscopic metastases, there was a positive correlation between serum BALP activity and absolute primary tumor size. In dogs with progressive OSA metastases, serum BALP activity increased and coincided with the development of macroscopic metastases. OSA cells derived from visceral metastatic lesions retained BALP expression. Tumor burden is a determinant of serum BALP activity in dogs with appendicular OSA. The association between increased pretreatment BALP activity and negative clinical prognosis may simply be attributed to greater initial tumor burden, and consequently more advanced tumor stage. Copyright © 2013 by the American College of Veterinary Internal Medicine.

Theoretical analysis of alendronate and risedronate effects on canine vertebral remodeling and microdamage

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Wang, Xiang; Erickson, Antonia M.; Allen, Matthew R.; Burr, David B.; Martin, R. Bruce; Hazelwood, Scott J.

2009-01-01

Bisphosphonates suppress bone remodeling activity, increase bone volume, and significantly reduce fracture risk in individuals with osteoporosis and other metabolic bone diseases. The objectives of the current study were to develop a mathematical model that simulates control and 1 year experimental results following bisphosphonate treatment (alendronate or risedronate) in the canine fourth lumbar vertebral body, validate the model by comparing simulation predictions to 3 year experimental res...

Comminuted mandibular fracture in child victim of dog bite.

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de Carvalho, Matheus Furtado; Hardtke, Luiz Augusto Paixão; de Souza, Max Filipe Cota; de Oliveira Araujo, Vasco

2012-08-01

Dog bites represent lesions commonly found in Hospital Emergency Clinic. This type of lesion may cause severe harm to patients, but it rarely affects the underlying bone structure causes facial fracture. This study aims to illustrate a rare clinical case in which a pediatric patient presented a comminuted fracture in the mandible which evolved into a unilateral avulsion of the mandibular condyle, body fractures as well as a mandibular ramus and hemiface that had been deformed, with multiple lacerations and loss of soft-tissue mass. Intermaxillary fixation was performed using the Ivy method, followed by internal rigid fixation using miniplates and screws in attempt to reconstruct the child's mandible. After 2 years of follow-up, a satisfactory esthetics and functional results could be observed. © 2011 John Wiley & Sons A/S.

Bone scintigraphy for metastasis detection in canine osteosarcoma

International Nuclear Information System (INIS)

Forrest, L.J.; Thrall, D.E.

1994-01-01

The purpose of this study was to assess the usefulness of serial bone scintigraphy in the detection of skeletal and extraskeletal metastases in dogs with appendicular osteosarcoma. Twenty-six dogs with primary, appendicular osteosarcoma were entered into a limb-sparing protocol. Bone scintigraphy was performed upon presentation, after neoadjuvant therapy but prior to surgery and at selective intervals after limb-sparing surgery to evaluate for the presence of metastasis. Thoracic radiographs, and radiographs of other sites, were also made at the time of each bone scan. All dogs had a complete necropsy. No dog had bone or lung metastases detected prior to treatment. The bone scans, medical records, and radiographs of each dog were reviewed retrospectively. All but one dog developed metastatic disease. Bone metastatic sites were confirmed at necropsy in 12 of the 26 dogs. Seven of these 12 dogs had bone metastatic sites which were not producing clinical signs, i.e. an occult metastasis. In five of the seven dogs, the occult site was the first metastatic site detected. Extraskeletal metastases were identified scintigraphically in six of the 26 dogs, but these were clinically apparent prior to bone scintigraphy in each dog. Suspected malignant scintigraphic lesions were proven benign in six dogs. In five dogs with malignant bone lesions at necropsy the last bone scan prior to euthanasia was normal. The time interval between scintigraphy and necropsy was variable in these five dogs. All dogs without bone metastases at necropsy had normal bone scans. This study validates the usefulness of bone scintigraphy for detection of occult bone metastasis and improved ability for tumor staging in dogs with appendicular osteosarcoma

Alveolar process fractures in the permanent dentition. Part 1. Etiology and clinical characteristics. A retrospective analysis of 299 cases involving 815 teeth

DEFF Research Database (Denmark)

Andreasen, Jens Ove; Lauridsen, Eva

2015-01-01

were present in 73%. The most frequent location of the mandibular fracture line was along the periodontal ligament of the canine and in the sagittal suture between the two central maxillary incisors. This pattern appears to correlate with weak zones in the jaws. CONCLUSION: In conclusion, alveolar...... resistance gives in, namely the periodontal ligament and areas where the alveolar bone is thin....

Pyogenic granuloma associated with mandibular odontoma.

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Karla Ocampo

2014-08-01

Full Text Available Background: pyogenic granuloma is a kind of inflammatory hyperplasia of multifactorial origin, which is usually related to trauma or constant irritation, drug use, hormonal factors, among others. Meanwhile the odontoma is a benign tumor odontogenic composed of epithelial and mesenchymal cells, their development is usually associated with trauma, infections, inherited disorders or hyperactivity odontoblast. Objectives: The objective is to present the clinical case of a patient that presented a case of pyogenic granuloma related to the presence of a mandibular odontoma, and therapeutic management and postoperative results. Case report: The case shows a female patient of 32 years old with a history of multinodular goiter and hypothyroidism, developing a mandibular odontoma of the left side associated with pyogenic granuloma in the same area, which was treated with surgical excision and reconstructed affected tissues with lyophilized bone and collagen membrane. Favorable outcome after surgery without evidence of recurrence, with proper osseointegration of alloplastic materials and soft tissues. Conclusions: The irritant effect of the presence of a tumor (odontoma in developing confirmed pyogenic granuloma.

Bilaterally impacted mandibular supernumerary premolars associated with unusual clinical complications

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Zameer Pasha

2013-01-01

Full Text Available Supernumerary teeth are extra teeth in comparison to the normal dentition. Their prevalence varies between 0.1% and 3.8%. Supernumeraries are more common in permanent dentition and its incidence is higher in maxillary incisor region, followed by maxillary third molar and mandibular molar, premolar, canine, and lateral incisor. The prevalence of supernumerary premolars is between 0.075-0.26%, and they may occur in single or multiple numbers Bilateral occurrence is uncommon and large percentage of supernumerary premolars remains impacted, unerupted, and usually asymptomatic; radiograph plays an important role in diagnosis of these. The present paper reports a case of bilaterally impacted completely developed supernumerary premolars associated with common clinical complication in unusual manner along with taurodontism of the upper and lower molars.

Compound odontoma associated with an unerupted mandibular primary canine: A case report

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Seraj B

2007-06-01

Full Text Available Odontomas are benign tumors of odontogenic origin characterized by their slow growth. They are considered to be a common type of odontogenic tumor, but rarely occur in the primary dentition.The etiology of odontomas is unknown, although local trauma, infection and genetic factors have been suggested. Odontomas often cause disturbances in the eruption of teeth such as, impaction or delayed eruption, and retention of primary teeth and abnormalities in the position of teeth such as tipping or displacement of adjacent teeth. In this paper, a case of unerupted right mandibular primary cuspid in a 5 years old girl due to the presence of a compound odontoma is presented.

Interpretation of mandibular condyle fractures using 2D- and 3D-computed tomography

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Costa e Silva Adriana Paula de Andrade da

2003-01-01

Full Text Available Computed tomography (CT has been increasingly used in the examination of patients with craniofacial trauma. This technique is useful in the examination of the temporomandibular joint and allows the diagnosis of fractures of the mandibular condyle. Aiming to verify whether the three-dimensional reconstructed images from CT (3D-CT produce more effective visual information than the two-dimensional (2D-CT ones, we evaluated 2D-CT and 3D-CT examinations of 18 patients with mandibular condyle fractures. We observed that 2D-CT and 3D-CT reconstructed images produced similar information for the diagnosis of fractures of the mandibular condyle, although the 3D-CT allowed a better visualization of the position and displacement of bone fragments, as well as the comminution of fractures. These results, together with the possibility of refining and manipulating perspectives in 3D images, reinforce the importance of its use in the surgical planning and evaluation of treatment. We concluded that 3D-CT presented supplementary information for a more effective diagnosis of mandibular condyle fractures.

Osteossíntese mandibular em jiboia (Boa constrictor)

OpenAIRE

Castro, Jorge Luiz Costa; Pontíficia Universidade Católica do Paraná; Santalucia, Sérgio; Universidade Federal de Santa Maria; Pachaly, José Ricardo; Universidade Paranaense; Villanova Junior, José Ademar; Pontífica Universidade Católica do Paraná; Castro, Verônica Souza Paiva; Universidade Federal de Santa Maria; Balthazar, Daniel Almeida; Fundação RIOZOO - RJ.; Spadetti, Alex Lucas; Fundação Parque Jardim Zoológico; Souza, Wilker Nazareth; Universidade Castelo Branco; Fedullo, Luiz Paulo Luzes; Fundação RIOZOO - RJ; Raiser, Alceu Gaspar; Universidade Federal de Santa Maria

2014-01-01

Nowadays are observed an increase in the finding of certain wild animals in urban areas, due to environmental changes caused by deforestation and economic use of natural areas. It causes disappearance of usual prey and forces these animals, including snakes, to migrate to urban areas, becoming vulnerable to injuries caused by aggressions, car accidents and capture. Mandibular and maxillar fractures are common in many animal species, representing about 3-6% of all bone fractures in dogs and ca...

Restricted Mandibular Movement Attributed to Ossification of Mandibular Depressors and Medial Pterygoid Muscles in Patients With Fibrodysplasia Ossificans Progressiva: A Report of 3 Cases.

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Okuno, Tetsuko; Suzuki, Hitoshi; Inoue, Akio; Kusukawa, Jingo

2017-09-01

Fibrodysplasia ossificans progressiva (FOP) is an extremely rare genetic condition characterized by congenital malformation and progressive heterotopic ossification (HO) caused by a recurrent single nucleotide substitution at position 617 in the ACVR1 gene. As the condition progresses, HO leads to joint ankylosis, breathing difficulties, and mouth-opening restriction, and it can shorten the patient's lifespan. This report describes 3 cases of FOP confirmed by genetic testing in patients with restricted mouth opening. Each patient presented a different onset and degree of jaw movement restriction. The anatomic ossification site of the mandibular joint was examined in each patient using reconstructed computed tomographic (CT) images and 3-dimensional reconstructed CT (3D-CT) images. A 29-year-old woman complained of jaw movement restriction since 13 years of age. 3D-CT image of the mandibular joint showed an osseous bridge, formed by the mandibular depressors that open the mouth, between the hyoid bone and the mentum of the mandible. A 39-year-old man presented with jaw movement restriction that developed at 3 years of age after a mouth injury. 3D-CT image of the jaw showed ankylosis of the jaw from ossification of the mandibular depressors that was worse than in patient 1. CT images showed no HO findings of the masticatory muscles. To the authors' knowledge, these are the first 2 case descriptions of the anatomic site of ankylosis involving HO of the mandibular depressors in the jaw resulting from FOP. In contrast, a 62-year-old bedridden woman with an interincisal distance longer than 10 mm (onset, 39 years of age) had no HO of the mandibular depressors and slight HO of the medial pterygoid muscle on the right and left sides. These findings suggest that restricted mouth opening varies according to the presence or absence of HO of the mandibular depressors. Copyright © 2017. Published by Elsevier Inc.

3D-CT evaluation of secondary alveolar bone grafts in alveolar clefts

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Naitoh, Hiroshi; Nishimura, Yoshihiko [Kyoto Univ. (Japan). Graduate School of Medicine; Yamawaki, Yoshiroh [Kyoto Katsura Hospital (Japan); Morimoto, Naoki [Kobe City General Hospital (Japan)

2002-07-01

From 1994 to 2000, we treated 116 patients with cleft alveolus by secondary alveolar bone grafts, and 48 of them were evaluated morphologically with 3D-CT. The frequency of successful bony bridging was significantly higher in the group whose grafts were completely enveloped (including the anterior alveolar ridge) with a mucoperiosteal flap. The frequency was also significantly higher in the group who underwent bone grafts at the age of 13 or less, and canine eruptions did not influence the ratio. Some cases showed such an improved growth pattern of grafted bone that the shape of the affected maxilla resembled that of the normal side, after long-term follow-up observations. The growth increment was remarkable in anterior maxillary height. Orthodontic management guides the canine or incisor into the reconstructed area of the previous cleft. We surmise that the new occlusal position puts pressure on the grafted bone and promotes further osteogenesis. These findings show that it is important to produce sufficient bony bridge to guide the canine or incisor, not the volume of grafted bone, in secondary alveolar bone grafts. Long-term follow-up observation, after more than 2-3 years, is also necessary to evaluate secondary alveolar bone grafts. (author)

Changes in the fractal dimension, feret diameter, and lacunarity of mandibular alveolar bone during initial healing of dental implants.

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Önem, Erinç; Baksı, B Güniz; Sogur, Elif

2012-01-01

To evaluate the combination of fractal dimension (FD), lacunarity, and Feret diameter (FeD) to quantitatively characterize structural changes of mandibular alveolar bone around dental implants during initial healing. Three standard-sized regions of interest (ROIs) (mesial and distal crest and apical area) around implants and three ROIs of the same size in the alveolar bone on the contralateral side were analyzed on digital panoramic images. FD was calculated using the box-counting method, and lacunarity was calculated using the FracLac plugin of Image J software. FeD was measured in the same ROIs. Comparisons of the groups were done with the Dunnett test. Forty-two implants in the posterior mandibles of 21 patients were used for FD measurements. A total of 189 ROIs was segmented into binary images. Mean FD values for mesial, distal, and apical ROIs around implants were 1.26, 1.36, and 1.4, respectively. The mean FD of alveolar bone around premolars/molars was 1.39 for all ROIs. The mean FeD for mesial, distal, and apical ROIs around implants was 7.63, 7.86, and 8.02, respectively, whereas it ranged between 7.88 and 8.13 for premolar teeth. Mean lacunarity values for mesial, distal, and apical ROIs around implants were 0.53, 0.51, and 0.48, respectively. Lacunarity values for ROIs around premolars ranged between 0.45 and 0.50. No significant differences were observed in FD, FeD, or lacunarity measurements between ROIs around implants and around teeth. The satisfactory healing of bone following implant placement may be monitored by calculating FD, lacunarity, and FeD using digital panoramic images. Although preliminary, these values may alert the practitioner to any implants with loss of stability.

Orthodontic Camouflage: A Treatment Option – A Clinical Case Report

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Mazzini, William Ubilla; Torres, Fátima Mazzini

2017-01-01

Orthodontic camouflage provides an alternative treatment for angle III malocclusion since patients with limited economic resources cannot opt for orthognathic surgery, it being clear that correction will be achieved at the dental level and not at the bone complex. Objective: To determine an alternative treatment for patients who do not have the possibility of having orthognathic surgery. Clinical case: A 13-year-old female patient, dolico facial biotype with slightly concave profile, with Class III Skeletal by mandibular prognathism, anterior crossbite, anterior diastema, and large mandibular body, molar class, and canine III. Alexander technique brackets were placed; premolar extraction was not planned. Once the case was completed, the correction of the anterior crossbite was achieved, thanks to the use of the spaces that existed at the beginning of the treatment and also that a correct distalization of canines and retraction of the lower anterior segment were performed. PMID:29326524

Orthodontic Camouflage: A Treatment Option - A Clinical Case Report.

Science.gov (United States)

Mazzini, William Ubilla; Torres, Fátima Mazzini

2017-01-01

Orthodontic camouflage provides an alternative treatment for angle III malocclusion since patients with limited economic resources cannot opt for orthognathic surgery, it being clear that correction will be achieved at the dental level and not at the bone complex. To determine an alternative treatment for patients who do not have the possibility of having orthognathic surgery. A 13-year-old female patient, dolico facial biotype with slightly concave profile, with Class III Skeletal by mandibular prognathism, anterior crossbite, anterior diastema, and large mandibular body, molar class, and canine III. Alexander technique brackets were placed; premolar extraction was not planned. Once the case was completed, the correction of the anterior crossbite was achieved, thanks to the use of the spaces that existed at the beginning of the treatment and also that a correct distalization of canines and retraction of the lower anterior segment were performed.

Prognostic factors in canine appendicular osteosarcoma - a meta-analysis.

Science.gov (United States)

Boerman, Ilse; Selvarajah, Gayathri T; Nielen, Mirjam; Kirpensteijn, Jolle

2012-05-15

Appendicular osteosarcoma is the most common malignant primary canine bone tumor. When treated by amputation or tumor removal alone, median survival times (MST) do not exceed 5 months, with the majority of dogs suffering from metastatic disease. This period can be extended with adequate local intervention and adjuvant chemotherapy, which has become common practice. Several prognostic factors have been reported in many different studies, e.g. age, breed, weight, sex, neuter status, location of tumor, serum alkaline phosphatase (SALP), bone alkaline phosphatase (BALP), infection, percentage of bone length affected, histological grade or histological subtype of tumor. Most of these factors are, however, only reported as confounding factors in larger studies. Insight in truly significant prognostic factors at time of diagnosis may contribute to tailoring adjuvant therapy for individual dogs suffering from osteosarcoma. The objective of this study was to systematically review the prognostic factors that are described for canine appendicular osteosarcoma and validate their scientific importance. A literature review was performed on selected studies and eligible data were extracted. Meta-analyses were done for two of the three selected possible prognostic factors (SALP and location), looking at both survival time (ST) and disease free interval (DFI). The third factor (age) was studied in a qualitative manner. Both elevated SALP level and the (proximal) humerus as location of the primary tumor are significant negative prognostic factors for both ST and DFI in dogs with appendicular osteosarcoma. Increasing age was associated with shorter ST and DFI, however, was not statistically significant because information of this factor was available in only a limited number of papers. Elevated SALP and proximal humeral location are significant negative prognosticators for canine osteosarcoma.

Early diagnostics of temporomandibular joint structural elements injures caused by traumatic mandibular bone fractures.

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Pohranychna, Kh R; Stasyshyn, A R; Matolych, U D

2017-06-30

A rapidly increasing number of mandibular condylar fractures and some complications related to injuries of temporomandibular elements make this study important. Intra-articular disorders lead to secondary pathological findings such as osteoarthritis, deforming osteoarthrosis, and temporomandibular joint ankylosis that limits mouth opening, mastication, swallowing, breathing, and decreased/lost working capacity or disability. Early diagnosis of intra-articular disorders can prevent from long-lasting functional complications caused by temporomandibular joint injuries. This study was performed for the purpose of early detection and investigation of organic pathological changes in the cartilaginous and osseous tissues of the temporomandibular joint caused by traumatic fractures of the mandibular condyle. Twenty patients underwent a general clinical examination, magnetic resonance imaging (MRI), and immune-enzyme testing for biochemical markers of connective tissue injury (pyridinoline and deoxypyridinoline) in urine. Disk dislocation, deformation, adhesion, perforation or squeeze, tension or disruption of ligaments, and injury of articular surfaces are among complications of mandibular fractures that can be revealed on MRI. As regards biochemical findings, we revealed a sharp rise in the levels of pyridinoline and deoxypyridinoline before treatment and a lack of stabilization within 21 days of treatment.

Relationship between mandibular condyle and angle fractures and the presence of mandibular third molars.

Science.gov (United States)

Mah, Deuk-Hyun; Kim, Su-Gwan; Moon, Seong-Yong; Oh, Ji-Su; You, Jae-Seek

2015-02-01

We retrospectively evaluated the impact of mandibular third molars on the occurrence of angle and condyle fractures. This was a retrospective investigation using patient records and radiographs. The sample set consisted of 440 patients with mandibular fractures. Eruption space, depth and angulation of the third molar were measured. Of the 144 angle fracture patients, 130 patients had third molars and 14 patients did not. The ratio of angle fractures when a third molar was present (1.26 : 1) was greater than when no third molar was present (0.19 : 1; odds ratio, 6.58; Pcondyle fractures patients, the third molar was present in 84 patients and absent in 57 patients. The ratio of condyle fractures when a third molar was present (0.56 : 1) was lower than when no third molar was present (1.90 : 1; odds ratio, 0.30; Pfractures with third molars and the ratio of condyle fractures without a third molar were statistically significant. The occurrence of angle and condyle fractures was more affected by the continuity of the cortical bone at the angle than by the depth of a third molar. These results demonstrate that a third molar can be a determining factor in angle and condyle fractures.

Treatment of Mandibular Molar Class II Furcation Defects in Humans With Bovine Porous Bone Mineral in Combination With Plasma Rich in Growth Factors

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S. Sadat Mansouri

2012-01-01

Full Text Available Objective: The purpose of the present randomized clinical trial study was to compare the effectiveness of Bovine Porous Bone Mineral (BPBM with and without Plasma Rich in Growth Factors (PRGF in the treatment of mandibular Class II furcation defects.Materials and Methods: In seven patients, nine pairs of symmetric buccal or lingual mandibular class II furcation defects were treated. In each patient, one defect received BPBM (control and the other received BPBM/PRGF (test by random assignment. Clinical measurements were made both at baseline and 6-month evaluation.Results: Similar improvements were observed with both treatment modalities.Significant reductions were gained in the gingival index, probing depth and relative vertical clinical attachment level. Plaque index and gingival recession changes were not significant in both groups. The mean probing depth reductions were 2.67±0.87 mm for the control group and 3.22±1.56 mm for the test group(p<0.001. The mean relative vertical clinical attachment level gains were 1.57±0.96 mm (p<0.001 and 1.65±1.24 mm (p<0.004 in the control and test groups, respectively. In the test group, the relative horizontal clinical attachment level reduced from 5.87±0.96 mm to 4.58±1.02 mm (p<0.02. No significant differenceswere observed in all clinical parameters 6 months postoperatively between the two groups.Conclusion: The application of a combined technique using BPBM/PRGF, compared to the BPBM alone, resulted in greater healing, although not significant, in the treatment of mandibular class II furcation defects.

Comparison of Osteogenesis between Adipose-Derived Mesenchymal Stem Cells and Their Sheets on Poly-ε-Caprolactone/β-Tricalcium Phosphate Composite Scaffolds in Canine Bone Defects

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Yongsun Kim

2016-01-01

Full Text Available Multipotent mesenchymal stem cells (MSCs and MSC sheets have effective potentials of bone regeneration. Composite polymer/ceramic scaffolds such as poly-ε-caprolactone (PCL/β-tricalcium phosphate (β-TCP are widely used to repair large bone defects. The present study investigated the in vitro osteogenic potential of canine adipose-derived MSCs (Ad-MSCs and Ad-MSC sheets. Composite PCL/β-TCP scaffolds seeded with Ad-MSCs or wrapped with osteogenic Ad-MSC sheets (OCS were also fabricated and their osteogenic potential was assessed following transplantation into critical-sized bone defects in dogs. The alkaline phosphatase (ALP activity of osteogenic Ad-MSCs (O-MSCs and OCS was significantly higher than that of undifferentiated Ad-MSCs (U-MSCs. The ALP, runt-related transcription factor 2, osteopontin, and bone morphogenetic protein 7 mRNA levels were upregulated in O-MSCs and OCS as compared to U-MSCs. In a segmental bone defect, the amount of newly formed bone was greater in PCL/β-TCP/OCS and PCL/β-TCP/O-MSCs/OCS than in the other groups. The OCS exhibit strong osteogenic capacity, and OCS combined with a PCL/β-TCP composite scaffold stimulated new bone formation in a critical-sized bone defect. These results suggest that the PCL/β-TCP/OCS composite has potential clinical applications in bone regeneration and can be used as an alternative treatment modality in bone tissue engineering.

Osteogénesis por distracción en defectos mandibulares y su estabilidad esquelética a los 2 años de tratados Osteogenesis by distraction in mandibular defects and skeletal stability after two years of treatment

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Dadonim Vila Morales

2011-03-01

Full Text Available El presente estudio tiene como objetivo mostrar los resultados de la estabilidad esquelética a los 2 años de operados, de los primeros pacientes con hipoplasias mandibulares tratados con distracción osteogénica en nuestro país. Se trataron 11 hemimandíbulas en 7 pacientes con distracción osteogénica mandibular, con distractores marca Leibinger. El periodo de latencia fue de 72 horas, la distracción mandibular se aplicó a razón de 1,0 mm cada 12 horas y la contención fue de 8 semanas. Luego se inició el tratamiento ortodóncico posquirúrgico. Se evaluaron los resultados a través de estudios cefalométricos antes de la intervención, luego y a los 2 años del tratamiento hubo cambios esqueléticos posoperatorios significativos en las mediciones angulares cefalométricas SNB y ANB, con pTo show the results of the skeletal stability after 2 years of to be operated on from the first patients presenting with mandibular hypoplasias treated with osteogenic distraction in our country. Eleven hemi-mandibles in 7 patients using mandibular osteogenic distraction with Leibinger distraction device. Latency period was of 72 hours, mandibular distraction was applied at a rate of 1,0 mm each 12 hours and fixation was of 8 weeks. Then, postsurgical orthodontic treatment was started. There were significant postoperative skeletal changes. Results were assessed by cephalometry studies before intervention, after and at 2 years of treatment. Also, there were significant postoperative skeletal changes in SNB and ANB with p< 0,05. The arithmetic mean of the osteodistraction achieve in branch was of 7,5 mm and in the body it was of 8,0 mm. At 2 years there remain a mandibular bone stability of 88,8 % qualified as good. Occlusal changes were favorable. There were not complications involving the good course of patients treated. It was shown that the bone distraction is an effective method for treatment of mandibular defects.

Is The Late Mandibular Fracture From Third Molar Extraction a Risk Towards Malpractice? Case Report with the Analysis of Ethical and Legal Aspects

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Weuler dos Santos Silva

2017-06-01

Full Text Available Objectives: The present study reports a case of late mandibular fracture due to third molar extraction and highlights the inherent clinical, ethical and legal aspects related to this surgical complication. Material and Methods: A female patient underwent surgical procedure for the extraction of the mandibular right third molar. Two days after the surgery the patient reported pain and altered occlusion in the right side of the mandible. After clinical and radiographic re-examination, the diagnosis of late mandibular fracture was established. A second surgery, under general anaesthesia, was performed for the fixation of the mandibular bone. Results: The fractured parts were reduced and fixed with locking plate systems and 2 mm screws following load-sharing principles. The masticatory function showed optimal performance within 7 and 21 days after the surgery. Complete bone healing was observed within 1 year of follow-up. Conclusions: For satisfactory surgical outcomes, adequate surgical planning and techniques must be performed. Signed informed consents explaining the risks and benefits of the treatment must be used to avoid ethical and legal disputes in dentistry.

Ihh signaling regulates mandibular symphysis development and growth.

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Sugito, H; Shibukawa, Y; Kinumatsu, T; Yasuda, T; Nagayama, M; Yamada, S; Minugh-Purvis, N; Pacifici, M; Koyama, E

2011-05-01

Symphyseal secondary cartilage is important for mandibular development, but the molecular mechanisms underlying its formation remain largely unknown. Here we asked whether Indian hedgehog (Ihh) regulates symphyseal cartilage development and growth. By embryonic days 16.5 to 18.5, Sox9-expressing chondrocytes formed within condensed Tgfβ-1/Runx2-expressing mesenchymal cells at the prospective symphyseal joint site, and established a growth-plate-like structure with distinct Ihh, collagen X, and osteopontin expression patterns. In post-natal life, mesenchymal cells expressing the Ihh receptor Patched1 were present anterior to the Ihh-expressing secondary cartilage, proliferated, differentiated into chondrocytes, and contributed to anterior growth of alveolar bone. In Ihh-null mice, however, symphyseal development was defective, mainly because of enhanced chondrocyte maturation and reduced proliferation of chondroprogenitor cells. Proliferation was partially restored in dual Ihh;Gli3 mutants, suggesting that Gli3 is normally a negative regulator of symphyseal development. Thus, Ihh signaling is essential for symphyseal cartilage development and anterior mandibular growth.

Internal structure of mandible around mandibular molar using computed tomography. Anatomical consideration of molar anchorage in orthodontic treatment

International Nuclear Information System (INIS)

Enomoto, Yutaka; Yamashita, Daisuke; Saito, Katsuhiko; Kasai, Kazutaka

2008-01-01

For establishment of fine occlusion, facial profile and oral function in orthodontic treatment, molar anchorage in teeth movement is important manner in extracted cases. The aims of this study were to investigate the relationship between facial morphology and internal structure of mandibular body in molar region by computer tomography, and to discuss about molar anchorage in orthodontic treatment. The data for this study were obtained from 35 modern male Japanese skulls (mean age; 27 year-old, ranged from 18 year-old to 47 year-old). Measurement variables were FMA, SN to mandibular plane angle, gonial angle, alveolar breadth, cortical bone thickness of buccal and lingual sides, and the distance between dental root and cortical bone. As a result, alveolar breadth and the distance between dental root and cortical bone were narrow in long facial type, on the contrary, these variables were wide in short facial type. The result suggested that these variables were considered important factors as molar anchorage in extracted cases. (author)

Relation between agenesis and shape anomaly of maxillary lateral incisors and canine impaction

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Anísio Bueno de Carvalho

2012-12-01

Full Text Available OBJECTIVE: The purpose was to obtain information about the relation between agenesis and shape anomaly of maxillary lateral incisors and canine impaction. METHODS: Seventy-three patients with canine impaction and 73 control patients, without canine impaction, were evaluated. The mesiodistal distances of the maxillary lateral incisors adjacent to the impacted canines and the correspondent mandibular lateral incisors were measured. The adjacent lateral incisors were classified in: 1 - absent, 2 - small, 3 - peg-shaped, 4 - standard. RESULTS: The results showed that among the patients with impacted canines, there were 21 anomalous teeth (small and peg-shaped and among the control patients there were only three small and peg-shaped teeth, with a statistically significant difference (p = 0.001. No patients were found with impacted canines and absent lateral incisors. CONCLUSION: It was concluded that in patients with anomalous lateral incisors (small and peg-shaped there is a probability to present impacted canines and this must be considered.OBJETIVO: o objetivo foi obter informação sobre a relação existente entre a agenesia e/ou anomalia de forma de incisivos laterais superiores e impacção de caninos. MÉTODOS: foram avaliados 73 pacientes com impacção de caninos e 73 pacientes controle, sem impacção de caninos. Foram medidas as distâncias mesiodistais dos incisivos laterais superiores adjacentes aos caninos impactados e os incisivos laterais correspondentes inferiores. Os incisivos laterais adjacentes foram classificados em: 1 - ausentes; 2 - pequenos; 3 - conoides; 4 - normais. RESULTADOS: os resultados mostraram que no grupo de pacientes com caninos impactados foram encontrados 22 dentes anômalos (pequenos e conoides, e no grupo controle apenas três dentes pequenos e conoides, sendo uma diferença estatisticamente significativa (p=0,001. Não foram encontrados pacientes com canino impactado e incisivo lateral ausente. CONCLUS�

Assessment of Alveolar Bone Status in Middle Aged Chinese (40-59 Years with Chronic Periodontitis--Using CBCT.

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Haijiao Zhao

Full Text Available This study used con-beam computed tomography (CBCT to investigate the prevalence and severity of alveolar bone loss in middle-aged (40-59 years Chinese with chronic periodontitis.The study group comprised 145 dentate individuals aged 40 to 59 years residing in China who suffered from chronic periodontitis. CBCT and the application of NNT software were used to examine the level and location of alveolar bone loss.The study revealed that 40-59 year old patients with chronic periodontitis had severe bone loss. At 5,286 sites (34.7%, alveolar bone loss was mild; severe alveolar bone loss was found at 5,978 sites (39.2%. A comparison of bone loss in different jaws revealed that the area with the highest degree of bone loss was on the lingual side of the maxillary molar (56.3 ± 7.2%, and that the area with the lowest degree was primarily on the lingual side of the mandibular canine (27.5 ± 6.3%. There was a lower degree of alveolar bone loss in males than females. Differences were observed when comparing the incidence of bone loss between males and females (P < 0.05. Menopause in females and smoking in both genders may affect the level of bone loss. Male smokers experienced a greater degree of bone loss (41.67 ± 5.76% than male non-smokers (32.95 ± 4.31%. A 42.23 ± 6.34% bone loss was found in menopausal females versus 31.35 ± 3.62% in non-menopausal females.The study revealed that different sites and teeth exhibited a diverse degree of bone loss. In middle-aged patients with chronic periodontitis, the highest degrees of bone loss in the incisors, premolars, and molars were on the lingual side, mesial side and lingual side, respectively. Menopause in females and smoking may affect the level of bone loss.

[Treatment of a patient with considerably thin alveolar bone and severe open bite].

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Haiya, Zhuo; Zhou, Hu; Qing, Zhao

2018-02-01

This case report describes the treatment of a 25-year-old woman with a severe open bite. This patient presented a grade Ⅲ open bite, considerably thin alveolar bone, and evident labial buccal and lingual root form. The open bite was corrected by fixed orthodontic treatment and masticatory exercises. However, the increased pressure in the labial muscle caused by lip muscle exercise suppressed the canines, which resulted in the protrusion of the apices of canine roots out of the alveolar bone. Afterward, HX brackets, instead of self-locking, were used and bonded reversely in the occlusal-gingival direction on the upper canines. The lip muscle exercises were decreased. After adjustment, the roots penetrated back into the cancellous bone, the severe open bite was corrected, and a normal overbite and overjet were achieved. ClassⅠcanine and molar relationships were established. The masticatory function and profile were both considerably improved. This case report showed that a severe nonskeletal open bite can be corrected using orthodontic treatments combined with masticatory exercises.

An unusual cause for trismus caused by mandibular coronoid osteoma: a case report

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Vashishth, Shirin; Garg, Kanika; Patil, Prashant; Sreenivasan, Venkatraman [Dept. of Oral Medicine and Radiology, Subharati Dental College, Meerut (India)

2013-03-15

Osteoma is a dense bony proliferation of otherwise normal membranous bone. This tumor is essentially restricted to the craniofacial skeleton and is rarely diagnosed in other bones. The mandible and the paranasal sinuses are the most common sites, while the involvement of the coronoid process has been reported in only 6 cases so far. This report demonstrated a case of osteoma occurring at the mandibular coronoid process in a 26-year-old female patient. The patient was managed with surgical resection of the osteoma followed by physiotherapy.

An unusual cause for trismus caused by mandibular coronoid osteoma: a case report

International Nuclear Information System (INIS)

Vashishth, Shirin; Garg, Kanika; Patil, Prashant; Sreenivasan, Venkatraman

2013-01-01

Osteoma is a dense bony proliferation of otherwise normal membranous bone. This tumor is essentially restricted to the craniofacial skeleton and is rarely diagnosed in other bones. The mandible and the paranasal sinuses are the most common sites, while the involvement of the coronoid process has been reported in only 6 cases so far. This report demonstrated a case of osteoma occurring at the mandibular coronoid process in a 26-year-old female patient. The patient was managed with surgical resection of the osteoma followed by physiotherapy.

CT findings of the infraorbital space. Special reference to odontogenic infection caused by periapical lesions of the maxillary canine

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Ikarugi, Yuko; Tanaka, Ray; Hayashi, Takafumi

2008-01-01

The purpose of this study was to estimate the clinical significance of the infraorbital space demonstrated on CT for the diagnosis of odontogenic infection caused by periapical lesions of the maxillary canine tooth. We evaluated the radiological appearance of the labial cortical bone and the surrounding soft tissue adjacent to the root apex of the maxillary canine in 12 patients with infraorbital space infection demonstrated on CT. The patients consisted of 6 males and 6 females, and age ranged from 33 to 84 years with a mean age of 58.7 years. On CT, disruption of the labial cortical bone around the root apex of the maxillary canine accompanied with pathological soft tissue density adjacent to the disrupted cortical bone was observed in all of the cases. Swelling of the facial muscles (levator labii superioris muscle, levator anguli oris muscle) was shown in 6 (50%) of 12 cases. Deviation of the levator labii superioris muscle was demonstrated in 9 cases (75%), whereas that of the levator anguli oris muscle was observed only in 2 cases (17%). The anatomical appearance of the infraorbital space which is clearly demonstrated on CT might be useful in diagnosing the spread of odontogenic infection caused by periapical lesions of the maxillary canine. (author)

American Canine Hepatozoonosis

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Ewing, S. A.; Panciera, R. J.

2003-01-01

American canine hepatozoonosis (ACH) is a tick-borne disease that is spreading in the southeastern and south-central United States. Characterized by marked leukocytosis and periosteal bone proliferation, ACH is very debilitating and often fatal. Dogs acquire infection by ingesting nymphal or adult Gulf Coast ticks (Amblyomma maculatum) that, in a previous life stage, ingested the parasite in a blood meal taken from some vertebrate intermediate host. ACH is caused by the apicomplexan Hepatozoon americanum and has been differentiated from Old World canine hepatozoonosis caused by H. canis. Unlike H. canis, which is transmitted by the ubiquitous brown dog tick (Rhipicephalus sanguineus), H. americanum is essentially an accidental parasite of dogs, for which Gulf Coast ticks are not favored hosts. The geographic portrait of the disease parallels the known distribution of the Gulf Coast tick, which has expanded in recent years. Thus, the endemic cycle of H. americanum involves A. maculatum as definitive host and some vertebrate intermediate host(s) yet to be identified. Although coyotes (Canis latrans) are known to be infected, it is not known how important this host is in maintaining the endemic cycle. This review covers the biology of the parasite and of the tick that transmits it and contrasts ACH with classical canine hepatozoonosis. Clinical aspects of the disease are discussed, including diagnosis and treatment, and puzzling epidemiologic issues are examined. Brief consideration is given to the potential for ACH to be used as a model for study of angiogenesis and of hypertrophic osteoarthropathy. PMID:14557294

Mandibular reconstruction in the radiated patient: the role of osteocutaneous free tissue transfers

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Duncan, M.J.; Manktelow, R.T.; Zuker, R.M.; Rosen, I.B.

1985-01-01

This paper discusses our experience with the second metatarsal and iliac crest osteocutaneous transfers for mandibular reconstruction. The prime indication for this type of reconstruction was for anterior mandibular defects when the patient had been previously resected. Midbody to midbody defects were reconstructed with the metatarsal and larger defects with the iliac crest. In most cases, an osteotomy was done to create a mental angle. The evaluation of speech, oral continence, and swallowing revealed good results in all patients unless lip or tongue resection compromised function. Facial contour was excellent in metatarsal reconstructions. The iliac crest cutaneous flap provided a generous supply of skin for both intraoral reconstruction and external skin coverage but tended to be bulky, particularly when used in the submental area. Thirty three of 36 flaps survived completely. Flap losses were due to anastomosis thrombosis (1), pedicle compression (1), and pedicle destruction during exploration for suspected carotid blowout (1). Ninety three percent of bone junctions developed a solid bony union despite the mandible having had a full therapeutic dose of preoperative radiation. Despite wound infections in 8 patients, and intraoral dehiscence with bone exposure in 12 patients, all but one of these transfers went on to good bony union without infection in the bone graft

Mandibular reconstruction in the radiated patient: the role of osteocutaneous free tissue transfers

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Duncan, M.J.; Manktelow, R.T.; Zuker, R.M.; Rosen, I.B.

1985-12-01

This paper discusses our experience with the second metatarsal and iliac crest osteocutaneous transfers for mandibular reconstruction. The prime indication for this type of reconstruction was for anterior mandibular defects when the patient had been previously resected. Midbody to midbody defects were reconstructed with the metatarsal and larger defects with the iliac crest. In most cases, an osteotomy was done to create a mental angle. The evaluation of speech, oral continence, and swallowing revealed good results in all patients unless lip or tongue resection compromised function. Facial contour was excellent in metatarsal reconstructions. The iliac crest cutaneous flap provided a generous supply of skin for both intraoral reconstruction and external skin coverage but tended to be bulky, particularly when used in the submental area. Thirty three of 36 flaps survived completely. Flap losses were due to anastomosis thrombosis (1), pedicle compression (1), and pedicle destruction during exploration for suspected carotid blowout (1). Ninety three percent of bone junctions developed a solid bony union despite the mandible having had a full therapeutic dose of preoperative radiation. Despite wound infections in 8 patients, and intraoral dehiscence with bone exposure in 12 patients, all but one of these transfers went on to good bony union without infection in the bone graft.

Clinical evaluation of porous hydroxyapatite bone graft (Periobone G with and without collagen membrane (Periocol in the treatment of bilateral grade II furcation defects in mandibular first permanent molars

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Sruthy Prathap

2013-01-01

Full Text Available Background: Furcation invasions represent one of the most demanding therapeutic challenges in periodontics. This investigation assessed and compared the clinical efficacy of hydroxyapatite bone graft material when used alone and with collagen membrane in the treatment of grade II furcation defects. Materials and Methods: Ten patients with comparable bilateral furcation defects in relation to mandibular first molars were selected and treated in a split-mouth design. After the hygiene phase of therapy was completed, the groups were selected randomly either for treatment with hydroxyapatite bone graft (Periobone G alone or with a combination of bone graft and guided tissue regeneration (GTR membrane (Periocol. Clinical parameters like plaque index, gingival index, vertical probing depth, horizontal probing depth, clinical attachment level, position of marginal gingiva, and the amount of bone fill were used at baseline and at 3 and 6 months postoperatively. Results: At 6 months, both surgical procedures resulted in statistically significant reduction in vertical and horizontal probing depths and gain in the clinical attachment level. Conclusion: The use of combination technique yielded superior results compared to sites treated with bone graft alone. However, the difference was not statistically significant.

Comparison of a novel bone-tendon allograft with a human dermis-derived patch for repair of chronic large rotator cuff tears using a canine model.

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Smith, Matthew J; Cook, James L; Kuroki, Keiichi; Jayabalan, Prakash S; Cook, Cristi R; Pfeiffer, Ferris M; Waters, Nicole P

2012-02-01

This study tested a bone-tendon allograft versus human dermis patch for reconstructing chronic rotator cuff repair by use of a canine model. Mature research dogs (N = 15) were used. Radiopaque wire was placed in the infraspinatus tendon (IST) before its transection. Three weeks later, radiographs showed IST retraction. Each dog then underwent 1 IST treatment: debridement (D), direct repair of IST to bone with a suture bridge and human dermis patch augmentation (GJ), or bone-tendon allograft (BT) reconstruction. Outcome measures included lameness grading, radiographs, and ultrasonographic assessment. Dogs were killed 6 months after surgery and both shoulders assessed biomechanically and histologically. BT dogs were significantly (P = .01) less lame than the other groups. BT dogs had superior bone-tendon, tendon, and tendon-muscle integrity compared with D and GJ dogs. Biomechanical testing showed that the D group had significantly (P = .05) more elongation than the other groups whereas BT had stiffness and elongation characteristics that most closely matched normal controls. Radiographically, D and GJ dogs showed significantly more retraction than BT dogs (P = .003 and P = .045, respectively) Histologically, GJ dogs had lymphoplasmacytic infiltrates, tendon degeneration and hypocellularity, and poor tendon-bone integration. BT dogs showed complete incorporation of allograft bone into host bone, normal bone-tendon junctions, and well-integrated allograft tendon. The bone-tendon allograft technique re-establishes a functional IST bone-tendon-muscle unit and maintains integrity of repair in this model. Clinical trials using this bone-tendon allograft technique are warranted. Copyright © 2012 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Accuracy of panoramic radiography and linear tomography in mandibular canal localization

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Bashizadeh Fakhar H.

2008-10-01

Full Text Available "nBackground and Aim: Accurate bone measurements are essential to determine the optimal size and length of dental implants. The magnification factor of radiographic images may vary with the imaging technique used. The purpose of this study was to compare the accuracy of linear tomography and panoramic radiography in vertical measurements, as well as the accuracy of linear tomography in mandibular width estimation. "nMaterials and Methods: In this test evaluation study, the vertical distances between the crest and the superior border of the inferior alveolar canal, marked with a metal ball, was measured by linear tomography and panoramic radiography in 23 sites of four dry mandible bones. Also the mandibular width was measured at the same sites. Then, the bones were sectioned through the marked spots and the radiographic measurements were compared with actual values. "nResults: The vertical magnification factor in tomograms and panoramic radiographs was 1.79 (SD=0.17 and 1.69 (SD=0.23, respectively. The horizontal magnification of tomograms was 1.47 (SD=0.17. A significant correlation was found between the linear tomographic and actual values, regarding vertical dimensions (p<0.001, r=0.968 and width (p<0.001, r=0.813. The correlation was significant but lower in panoramic radiographs (p<0.001, r=0.795. Applying the magnification values suggested by the manufacturer, the mean difference of vertical measurements between the tomographic sections was 2.5 mm (SD=3.4 but 3.8 mm (SD=1.65 in panoramic radiographs. The mean of absolute difference in mandibular width between the tomographic sections and reality was 0.3mm (SD=1.13. In the linear tomograms, 4.3% of vertical and 56.5% of the width measurements were in the ±1mm error limit. Only 4.3% of the vertical measurements were within this range in the panthomographs. The linear regression equation between the actual values and those obtained by radiography in vertical dimensions showed that 87.5% of

Radioresistant canine hematopoietic cells

International Nuclear Information System (INIS)

Kawakami, T.G.; Shimizu, J.; Rosenblatt, L.S.; Goldman, M.

1987-01-01

Survival of dogs that are continuously exposed to a moderate dose-rate of gamma radiation (10 cGy/day) is dependent on the age of the dog at the time of exposure. Most dogs exposed postpartum to gamma radiation suffered from suppressed hematopoiesis and died of aplasia. On the other hand, none of the in utero-exposed dogs suffered from suppressed hematopoiesis and most became long-term survivors, tolerating 10-fold greater total dose, but dying of myeloproliferative disease (MPD). Using acute gamma irradiation of hematopoietic cells and colony forming unit cell assay (CFU), they observed that a canine hematopoietic cell line established from a myeloid leukemic dog that was a long-term survivor of continuous irradiation was approximately 4-fold more radioresistant than a hematopoietic cell line established from a dog with nonradiation-induced myeloid leukemia or hematopoietic cells from normal canine bone marrow. In utero dogs that are long-term survivors of continuous irradiation have radioresistant hematopoietic cells, and radioresistance that is a constitutive property of the cells

[Three-dimensional modeling of mandibular distraction].

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Morgon, L A; Trunde, F; Coudert, J L; Disant, F

2003-12-01

Facial hemi-atrophy affects 1 in 4000 or 5000 children. We propose treating this deformation of the 1st branchial arch with the "bone distraction" lengthening technique first described by Ilizarov in the 1950s, which has already been employed with the mandible. We have modelled mandibular distraction in facial hemi-atrophy patients and discuss the benefits of such pre-surgical planning encompassing the assistance of pre- and post-operative as well as surgically coordinated orthodontic therapy. Using X scanner views of a 5 year-old girl patient, we have developed a distraction-simulation software, which makes the pathological side harmonious with the healthy side along the medial sagittal plane. In order to obtain facial symmetry, put bones in balance, and orient the occlusal plane horizontally, essential requisites of occlusal stability, it is necessary: to employ a 2 or 3-dimensional distractor, to pre-plan the distraction and screw positioning, to set up a fixed orthodontic treatment plan prior to beginning distraction therapy.

Evaluation of reference gene suitability for quantitative expression analysis by quantitative polymerase chain reaction in the mandibular condyle of sheep.

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Jiang, Xin; Xue, Yang; Zhou, Hongzhi; Li, Shouhong; Zhang, Zongmin; Hou, Rui; Ding, Yuxiang; Hu, Kaijin

2015-10-01

Reference genes are commonly used as a reliable approach to normalize the results of quantitative polymerase chain reaction (qPCR), and to reduce errors in the relative quantification of gene expression. Suitable reference genes belonging to numerous functional classes have been identified for various types of species and tissue. However, little is currently known regarding the most suitable reference genes for bone, specifically for the sheep mandibular condyle. Sheep are important for the study of human bone diseases, particularly for temporomandibular diseases. The present study aimed to identify a set of reference genes suitable for the normalization of qPCR data from the mandibular condyle of sheep. A total of 12 reference genes belonging to various functional classes were selected, and the expression stability of the reference genes was determined in both the normal and fractured area of the sheep mandibular condyle. RefFinder, which integrates the following currently available computational algorithms: geNorm, NormFinder, BestKeeper, and the comparative ΔCt method, was used to compare and rank the candidate reference genes. The results obtained from the four methods demonstrated a similar trend: RPL19, ACTB, and PGK1 were the most stably expressed reference genes in the sheep mandibular condyle. As determined by RefFinder comprehensive analysis, the results of the present study suggested that RPL19 is the most suitable reference gene for studies associated with the sheep mandibular condyle. In addition, ACTB and PGK1 may be considered suitable alternatives.

Endoscopically assisted enucleation of a large mandibular periapical cyst.

Science.gov (United States)

Nestal Zibo, Heleia; Miller, Ene

2011-01-01

Enucleation of large cysts in the jaws is an invasive method that might be associated with complications. Marsupialization is a less invasive alternative method but it involves a prolonged and uncomfortable healing period. This study addresses a contemporaneous and less invasive surgical technique for treating larger mandibular cysts. MATERIALS AND METHODS. A 48-year-old woman presented with a large mandibular apical cyst involving the left parasymphysis, body, ramus and condylar neck, with involvement of the alveolar inferior nerve. The cystic lesion was enucleated using a 30° 4.0 mm endoscopic scope and endoscopic instruments through two small accesses: the ostectomy site of previously performed marsupialization and the alveolus of the involved third molar extracted of the time of the enucleation of the cyst. RESULTS. The endoscopic scope provided good visualization of the whole cystic cavity allowing the removal of any residual pathologic tissue and preservation of the integrity of the involved inferior alveolar nerve. The morbidity of the surgical procedure was extremely reduced. At a 6-month follow-up the patient did not present any symptom of inflammation and a panoramic X-ray showed good bone repair and remodelation. CONCLUSIONS. Endoscopically assisted enucleation proved to be effective method of treating a large mandibular cyst, providing total enucleation with a minimal invasive technique.

Dislocation of temporo-mandibular joint - an uncommon circumstance of occurrence: vaginal delivery.

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El Bouazzaoui, Abderrahim; Labib, Smael; Derkaoui, Ali; Adnane Berdai, Mohammed; Bendadi, Azzeddine; Harandou, Mustapha

2010-06-25

Dislocation of temporo-mandibular joint (TMJ) is an infrequent disease but still spectacular. This disease consists of a permanent, to some extent complete disruption of the temporo-mandibular joint. These dislocations often occur in a context of yawning, and less frequently after a burst of laughing or relatively mild facial trauma (slap, punch on the chin). We report a case of TMJ occurring in an uncommon circumstance: vaginal delivery. A woman aged 24-years with no special past medical history; primipara was admitted in the Department of Maternity of the University Hospital Hassan II of Fez for an imminent delivery of a twin pregnancy. Ten minutes after admission, the patient delivered vaginally with episiotomy. She gave birth to twins weighing 2800 g and 2400 g. During labour, and due to efforts of crying, the patient developed a sudden and immediate loss of function of the temporo-mandibular joint, with difficulty of speaking, the mouth permanently opened and with the chin lowered and thrown forward. The examination found an empty glenoid fossa of the temporo-mandibular joint in both sides. The diagnosis of dislocation of the TMJ was established. A CT scan of facial bones was done, objectifying a bilateral dislocation of TMJ. The reduction of this dislocation was performed in the operating room under sedation.

Prosthodontic rehabilitation of patient with marginal mandibular resection using attachment supported prostheses: A clinical report

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Kailas Mundhe

2014-01-01

Full Text Available Marginal mandibular resection to treat neoplasms leads to loss of alveolar bone and teeth at the affected side. Consequently patient suffers with poor masticatory performance and esthetic disfigurement, which we need to restore with the help of prosthodontic rehabilitation. The success of rehabilitation of these patients depends on strategic treatment planning and choice of most suitable treatment modality. In this article, case of a patient has been presented who underwent marginal mandibular resection and reported with many limiting factors like obliterated buccal and lingual sulci, attachment of lingual frenum and lower lip at the level of alveolar ridge and Macroglossia. Impression making and fabrication of a retentive prosthesis were the main challenges. Therefore, a modified impression technique was used to fabricate mandibular cast partial denture with extracoronal semi precision attachments to enhance the retention of the prosthesis.

Fixation of zygomatic and mandibular fractures with biodegradable plates.

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Degala, Saikrishna; Shetty, Sujeeth; Ramya, S

2013-01-01

In this prospective study, 13 randomly selected patients underwent treatment for zygomatic-complex fractures (2 site fractures) and mandibular fractures using 1.5 / 2 / 2.5-mm INION CPS biodegradable plates and screws. To assess the fixation of zygomatic-complex and mandibular fractures with biodegradable copolymer osteosynthesis system. In randomly selected 13 patients, zygomatic-complex and mandibular fractures were plated using resorbable plates and screws using Champy's principle. All the cases were evaluated clinically and radiologically for the type of fracture, need for the intermaxillary fixation (IMF) and its duration, duration of surgery, fixation at operation, state of reduction at operation, state of bone union after operation, anatomic reduction, paresthesia, occlusal discrepancies, soft tissue infection, immediate and late inflammatory reactions related to biodegradation process, and any need for the removal of the plates. Descriptives, Frequencies, and Chi-square test were used. In our study, the age group range was 5 to 55 years. Road traffic accidents accounted for the majority of patients six, (46.2%). Postoperative occlusal discrepancies were found in seven patients as mild to moderate, which resolved with IMF for 1-8 weeks. There were minimal complications seen and only as soft tissue infection. Use of biodegradable osteosynthesis system is a reliable alternative method for the fixation of zygomatic-complex and mandibular fractures. The biodegradable system still needs to be refined in material quality and handling to match the stability achieved with metal system. Biodegradable plates and screws is an ideal system for pediatric fractures with favorable outcome.

Maxillary complete denture outcome with two-implant supported mandibular overdentures. A systematic review.

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Rutkunas, Vygandas; Mizutani, Hiroshi; Peciuliene, Vytaute; Bendinskaite, Ruta; Linkevicius, Tomas

2008-01-01

Research data regarding maxillary complete denture outcome with two-implant supported mandibular overdentures are not consistent. Considering multiple publications on implant supported mandibular overdentures, it was decided to summarize currently present evidence on the maxillary complete dentures opposed by implant-supported mandibular overdentures, and analyze factors that could potentially influence the outcomes. The articles from 1985 to 2007 related to the topic were identified in the online MEDLINE/Pubmed and other databases and manually. Primary articles were scanned, and irrelevant studies were excluded from the further review process. Potentially relevant titles and abstracts were provisionally included for consideration on the basis of full text articles. Full text articles were obtained from on-line and printed sources. The data from the studies were extracted and reviewed. The study has failed to identify any prospective satisfying inclusion/exclusion criteria RCT reporting on maxillary bone resorption. The number of maxillary complete denture relining incidences per patient was constantly increasing during the 10-year period. Maxillary complete denture remake incidences comprised 16-33 % of the number of patients followed during the 10-year period. Comparing patient satisfaction with upper dentures at the baseline and after two years, no decrease in satisfaction was noticed. There is no evidence that maxillary ridge resorption is accelerated with certain types of two-implant supported mandibular overdenture attachments. Most common complication for the maxilla - prosthetic maintenance. There is a risk of decreased patient satisfaction with bar-supported mandibular overdenture. Further studies are needed to provide evidence for the maxillary complete denture outcome with two-implant supported mandibular overdentures.

Vivosorb as a barrier membrane in rat mandibular defects. An evaluation with transversal microradiography.

NARCIS (Netherlands)

Hoogeveen, E.J.; Gielkens, P.F.; Schortinghuis, J.; Ruben, J.L.; Huysmans, M.C.D.N.J.M.; Stegenga, B.

2009-01-01

Vivosorb is a new degradable membrane composed of poly(DL-lactide-epsilon-caprolactone) (PDLLCL). The aim of this study was to appraise its performance in guided bone regeneration procedures. In 192 rats a 5.0 mm defect was drilled in the mandibular angle. The defects were covered with a membrane

Pre-operative planning for mandibular reconstruction - A full digital planning workflow resulting in a patient specific reconstruction

Science.gov (United States)

2011-01-01

Objectives Reconstruction of large mandiblular defects following ablative oncologic surgery could be done by using vascularized bone transfer or, more often, primarily with simultaneous or delayed bone grafting, using load bearing reconstruction plates. Bending of these reconstruction plates is typically directed along the outer contour of the original mandible. Simultaneously or in a second operation vascularized or non-vascularized bone is fixed to the reconstruction plate. However, the prosthodontic-driven backward planning to ease bony reconstruction of the mandible in terms of dental rehabilitation using implant-retained overdentures might be an eligible solution. The purpose of this work was to develop, establish and clinically evaluate a novel 3D planning procedure for mandibular reconstruction. Materials and methods Three patients with tumors involving the mandible, which included squamous cell carcinoma in the floor of the mouth and keratocystic odontogenic tumor, were treated surgically by hemimandibulectomy. Results In primary alloplastic mandible reconstruction, shape and size of the reconstruction plate could be predefined and prebent prior to surgery. Clinical relevance This study provides modern treatment strategies for mandibular reconstruction. PMID:21968330

A Comparative Analysis of Recombinant Human Bone Morphogenetic Protein-2 with a Demineralized Bone Matrix versus Iliac Crest Bone Graft for Secondary Alveolar Bone Grafts in Patients with Cleft Lip and Palate: Review of 501 Cases.

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Hammoudeh, Jeffrey A; Fahradyan, Artur; Gould, Daniel J; Liang, Fan; Imahiyerobo, Thomas; Urbinelli, Leo; Nguyen, JoAnna T; Magee, William; Yen, Stephen; Urata, Mark M

2017-08-01

Alveolar cleft reconstruction using iliac crest bone graft is considered standard of care for children with complete cleft lip and palate at the time of mixed dentition. Harvesting bone may result in donor-site morbidity and additional operating time and length of hospitalization. Recombinant human bone morphogenetic protein (rhBMP)-2 with a demineralized bone matrix is an alternative bone source for alveolar cleft reconstruction. The authors investigated the outcomes of rhBMP-2/demineralized bone matrix versus iliac crest bone graft for alveolar cleft reconstruction by reviewing postoperative surgical complications and cleft closure. A retrospective chart review was conducted for 258 rhBMP-2/demineralized bone matrix procedures (mean follow-up, 2.9 years) and 243 iliac crest bone graft procedures (mean follow-up, 4.1 years) on 414 patients over a 12-year period. The authors compared complications, canine eruption, and alveolar cleft closure between the two groups. In the rhBMP-2/demineralized bone matrix group, one patient required prolonged intubation because of intraoperative airway swelling not thought to be caused by rhBMP-2, 36 reported facial swelling and one required outpatient steroids as treatment, and 12 had dehiscence; however, half of these complications resolved without intervention. Twenty-three of the 228 rhBMP-2/demineralized bone matrix patients and 28 of the 242 iliac crest bone graft patients required repeated surgery for alveolar cleft repair. Findings for canine tooth eruption into the cleft site through the graft were similar between the groups. The rhBMP-2/demineralized bone matrix appears to be an acceptable alternative for alveolar cleft repair. The authors found no increase in serious adverse events with the use of this material. Local complications, such as swelling and minor wound dehiscence, predominantly improved without intervention. Therapeutic, III.

Engraftment Efficiency after Intra-Bone Marrow versus Intravenous Transplantation of Bone Marrow Cells in a Canine Nonmyeloablative Dog Leukocyte Antigen-Identical Transplantation Model.

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Lange, Sandra; Steder, Anne; Killian, Doreen; Knuebel, Gudrun; Sekora, Anett; Vogel, Heike; Lindner, Iris; Dunkelmann, Simone; Prall, Friedrich; Murua Escobar, Hugo; Freund, Mathias; Junghanss, Christian

2017-02-01

An intra-bone marrow (IBM) hematopoietic stem cell transplantation (HSCT) is assumed to optimize the homing process and therefore to improve engraftment as well as hematopoietic recovery compared with conventional i.v. HSCT. This study investigated the feasibility and efficacy of IBM HSCT after nonmyeloablative conditioning in an allogeneic canine HSCT model. Two study cohorts received IBM HSCT of either density gradient (IBM-I, n = 7) or buffy coat (IBM-II, n = 6) enriched bone marrow cells. An historical i.v. HSCT cohort served as control. Before allogeneic HSCT experiments were performed, we investigated the feasibility of IBM HSCT by using technetium-99m marked autologous grafts. Scintigraphic analyses confirmed that most IBM-injected autologous cells remained at the injection sites, independent of the applied volume. In addition, cell migration to other bones occurred. The enrichment process led to different allogeneic graft volumes (IBM-I, 2 × 5 mL; IBM-II, 2 × 25 mL) and significantly lower counts of total nucleated cells in IBM-I grafts compared with IBM-II grafts (1.6 × 10 8 /kg versus 3.8 × 10 8 /kg). After allogeneic HSCT, dogs of the IBM-I group showed a delayed engraftment with lower levels of donor chimerism when compared with IBM-II or to i.v. HSCT. Dogs of the IBM-II group tended to reveal slightly faster early leukocyte engraftment kinetics than intravenously transplanted animals. However, thrombocytopenia was significantly prolonged in both IBM groups when compared with i.v. HSCT. In conclusion, IBM HSCT is feasible in a nonmyeloablative HSCT setting but failed to significantly improve engraftment kinetics and hematopoietic recovery in comparison with conventional i.v. HSCT. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Mandibular tori are associated with mechanical stress and mandibular shape.

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Cortes, Arthur Rodriguez Gonzalez; Jin, Zhaoyu; Morrison, Matthew Daniel; Arita, Emiko Saito; Song, Jun; Tamimi, Faleh

2014-11-01

The influence of mechanical stimulation on the formation of torus mandibularis (TM) is still poorly understood. We sought to understand the etiology of TMs by investigating the role of parafunctional activity and mandibular morphology on the formation of TMs. We designed a case-control study for patients attending the dental clinic of the present study (University of São Paulo School of Dentistry, São Paulo, SP, Brazil). Patients presenting with TMs were defined as cases, and those without TMs were defined as controls. Finite element analysis (FEA) was used in 3-dimensional mandibular models to examine the stress distribution in the mandibles with and without TMs. In addition, the associations of mandibular arch shape, mandibular cortical index, and parafunctional activity with the presence of T were assessed using odds ratio analysis. A total of 10 patients with TMs and 37 without TMs were selected (22 men and 25 women, mean age 54.3 ± 8.4 years). FEA showed a stress concentration in the region in which TMs form during simulation of parafunctional activity. The radiographic assessment showed that those with TMs were more likely to have a square-shaped mandible with sharp angles (P = .001) and a normal mandibular cortex (P = .03). The subjects without TMs had a round-shaped mandible with obtuse angles and an eroded mandibular cortex. Parafunctional activity could be causing the formation of TMs by concentrating mechanical stress in the region in which TMs usually form. Thus, mandibular geometries that favor stress concentration, such as square-shaped mandibles, will be associated with a greater prevalence of TMs. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Image-Based Macro-Micro Finite Element Models of a Canine Femur with Implant Design Implications

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Ghosh, Somnath; Krishnan, Ganapathi; Dyce, Jonathan

2006-06-01

In this paper, a comprehensive model of a bone-cement-implant assembly is developed for a canine cemented femoral prosthesis system. Various steps in this development entail profiling the canine femur contours by computed tomography (CT) scanning, computer aided design (CAD) reconstruction of the canine femur from CT images, CAD modeling of the implant from implant blue prints and CAD modeling of the interface cement. Finite element analysis of the macroscopic assembly is conducted for stress analysis in individual components of the system, accounting for variation in density and material properties in the porous bone material. A sensitivity analysis is conducted with the macroscopic model to investigate the effect of implant design variables on the stress distribution in the assembly. Subsequently, rigorous microstructural analysis of the bone incorporating the morphological intricacies is conducted. Various steps in this development include acquisition of the bone microstructural data from histological serial sectioning, stacking of sections to obtain 3D renderings of void distributions, microstructural characterization and determination of properties and, finally, microstructural stress analysis using a 3D Voronoi cell finite element method. Generation of the simulated microstructure and analysis by the 3D Voronoi cell finite element model provides a new way of modeling complex microstructures and correlating to morphological characteristics. An inverse calculation of the material parameters of bone by combining macroscopic experiments with microstructural characterization and analysis provides a new approach to evaluating properties without having to do experiments at this scale. Finally, the microstructural stresses in the femur are computed using the 3D VCFEM to study the stress distribution at the scale of the bone porosity. Significant difference is observed between the macroscopic stresses and the peak microscopic stresses at different locations.

Mandibular corpus bone strains during mastication in goats (Capra hircus): a comparison of ingestive and rumination chewing.

Science.gov (United States)

Williams, Susan H; Stover, Kristin K; Davis, Jillian S; Montuelle, Stephane J

2011-10-01

To compare the mechanical loading environment of the jaw in goats during ingestive and rumination chewing. Rosette strain gauges were attached to the external surface of the mandibular corpus in five goats to record bone strains during the mastication of hay and rumination. Strain magnitudes and maximum physiological strain rates during the mastication of hay are significantly higher than during rumination chewing on the working and balancing sides. Principal strain ratios and orientations are similar between the two chewing behaviours. Loading and chewing cycle duration are all longer during rumination chewing, whereas chew duty factor and variances in load and chewing cycle durations are higher during ingestive chewing. For most of the variables, differences in strain magnitudes or durations are similar at all three gauge sites, suggesting that rumination and ingestive chewing do not differentially influence bone at the three gauge sites. Despite lower strain magnitudes, the repetitive nature of rumination chewing makes it an important component of the mechanical loading environment of the selenodont artiodactyl jaw. However, similarities in principal strain orientations and ratios indicate that rumination chewing need not be considered as a unique loading behaviour influencing the biomechanics of the selenodont artiodactyl jaw. Differences in loading and chewing cycle durations during rumination and ingestion demonstrate flexibility in adult chewing frequencies. Finally, although the low within-sequence variability in chewing cycle durations supports the hypothesis that mammalian mastication is energetically efficient, chewing during rumination may not be more efficient than during ingestion. Copyright © 2011 Elsevier Ltd. All rights reserved.

The role of osteonecrosis in canine coronoid dysplasia: Arthroscopic and histopathological findings

NARCIS (Netherlands)

Mariee, I.C.; Gröne, A.; Theyse, L.F.H.

2014-01-01

Coronoid dysplasia (CD) or medial coronoid disease is part of canine elbowdysplasia and eventually results in osteoarthrosis. Although CDwas originally attributed to disturbed endochondral ossification,more recent data point to the subchondral bone. The objective of this study was to assess

Investigation of Peri-Implant Bone Healing Using Autologous Plasma Rich in Growth Factors in the Canine Mandible After 12 Weeks: A Pilot Study

Science.gov (United States)

Birang, Reza; Tavakoli, Mohammad; Shahabouei, Mohammad; Torabi, Alireza; Dargahi, Ali; Soolari, Ahmad

2011-01-01

Introduction: Faster reconstruction of patients’ masticatory systems is the aim of modern dentistry. A number of studies have indicated that application of growth factors to the surface of a dental implant leads to accelerated and enhanced osseointegration. The objective of the present study was to investigate the effect of plasma rich in growth factors on peri-implant bone healing. Materials and Methods: For the purpose of this study, two healthy, mixed-breed canines were selected, and the premolars were extracted from both sides of the mandible. Three months after premolar removal, 12 implants, each 5 mm in diameter and 10 mm in length, were placed in osteotomy sites on both sides of the mandible. Prior to placement, plasma rich in growth factors was applied to the surfaces of six implants, while the other six were used without plasma rich in growth factors. The implants were removed after 12 weeks along with the bone surrounding the sites using a trephine bur. One mesiodistal section containing the surrounding bone from each implant block, 50 µm in diameter, was prepared for histologic and histomorphometric investigation with an optical microscope. Results: The sites with implants treated with plasma rich in growth factors showed more bone-to-implant contact compared to control sites. Also, higher values for bone trabecular thickness and bone maturity were recorded for the PRGF-treated sites than for the control sites. Conclusion: Application of plasma rich in growth factors to the surface of an implant may enhance the bone healing process as well as bone-to-implant contact, thereby helping to achieve faster osseointegration. PMID:22145011

Comparación biomecánica entre los sistemas convencionales y uni-lock en osteosíntesis del ángulo mandibular: Estudio fotoelástico Biomechanical comparison of the conventional and uni-lock systems for mandibular osteosynthesis: A photoelastic study

Directory of Open Access Journals (Sweden)

José Luis Cebrián-Carretero

2012-03-01

Full Text Available Introducción: Las implicaciones biomecánicas de la interacción de las placas y tornillos de titanio con la mandíbula fracturada no son del todo conocidas. Los modelos matemáticos desarrollados hasta hoy en día muestran ciertas limitaciones, y los estudios experimentales han fracasado en reproducir las fuerzas musculares y la distribución de las tensiones internas en la interfaz entre mandíbula e implante. Material y métodos: En el presente estudio, empleamos un simulador estático del sistema músculo-esquelético masticatorio para demostrar en réplicas mandibulares de resina epoxi, por medio de la fotoelasticidad tridimensional, la distribución de tensiones que se produce en fracturas del cuerpo mandibular tras la aplicación de diferentes métodos de osteosíntesis. Resultados: Los resultados muestran que el simulador y la fotoelasticidad 3D son útiles para estudiar las interacciones entre el hueso y el material de osteosíntesis. Los sistemas «lock» o bloqueados reflejaron la distribución de tensiones más favorable en la mandíbula de resina epoxi fracturada. Conclusiones: La fotoelasticidad tridimensional en modelos de resina epoxi es un método útil para evaluar la distribución de tensiones en una estructura para estudios biomecánicos. En lo que se refiere a la osteosíntesis mandibular, las placas tipo «lock» mostraron ser las menos agresivas para el hueso.Introduction: The biomechanical effects of the interaction between titanium plates and screws and the fractured mandible are not well known. The mathematical models that have been developed to date show limitations and the experimental studies fail in reproducing muscle forces and internal stress distributions in the bone-implant interface with the mandibular structure. Material and methods: In the present study we use a static simulator of the masticatory system to show, in epoxy resin mandibular models, by means of 3D (three-dimensional photoelasticity, the stress

Renal cell carcinoma presenting as mandibular metastasis

Directory of Open Access Journals (Sweden)

Hassan Ahmadnia

2013-01-01

Full Text Available Renal clear cell carcinoma (RCC has different manifestations, including uncommon metastasis and paraneoplastic syndromes. Here we report a rare case of RCC presenting as metastasis to the mandible. A 57-year-old patient with mandibular swelling was referred to the dentist. After necessary evaluations, an incisional biopsy of mandible showed metastatic RCC. The patient was referred to the urologist. The patient underwent right radical nephrectomy. Pathological examination showed clear renal cell carcinoma. Every abnormal bone lesion in the oral cavity should be evaluated carefully and the possibility of a malignant lesion should always be considered.

Influence of implant number on the biomechanical behaviour of mandibular implant-retained/supported overdentures: a three-dimensional finite element analysis.

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Liu, Jingyin; Pan, Shaoxia; Dong, Jing; Mo, Zhongjun; Fan, Yubo; Feng, Hailan

2013-03-01

The aim of this study was to evaluate strain distribution in peri-implant bone, stress in the abutments and denture stability of mandibular overdentures anchored by different numbers of implants under different loading conditions, through three-dimensional finite element analysis (3D FEA). Four 3D finite element models of mandibular overdentures were established, using between one and four Straumann implants with Locator attachments. Three types of load were applied to the overdenture in each model: 100N vertical and inclined loads on the left first molar and a 100N vertical load on the lower incisors. The biomechanical behaviours of peri-implant bone, implants, abutments and overdentures were recorded. Under vertical load on the lower incisors, the single-implant overdenture rotated over the implant from side to side, and no obvious increase of strain was found in peri-implant bone. Under the same loading conditions, the two-implant-retained overdenture showed more apparent rotation around the fulcrum line passing through the two implants, and the maximum equivalent stress in the abutments was higher than in the other models. In the three-implant-supported overdenture, no strain concentration was found in cortical bone around the middle implant under three loading conditions. Single-implant-retained mandibular overdentures do not show damaging strain concentration in the bone around the only implant and may be a cost-effective treatment option for edentulous patients. A third implant can be placed between the original two when patients rehabilitated by two-implant overdentures report constant and obvious denture rotation around the fulcrum line. Copyright © 2012 Elsevier Ltd. All rights reserved.

Tissue engineering for lateral ridge augmentation with recombinant human bone morphogenetic protein 2 combination therapy: a case report.

Science.gov (United States)

Mandelaris, George A; Spagnoli, Daniel B; Rosenfeld, Alan L; McKee, James; Lu, Mei

2015-01-01

This case report describes a tissue-engineered reconstruction with recombinant human bone morphogenetic protein 2/acellular collagen sponge (rhBMP-2/ ACS) + cancellous allograft and space maintenance via Medpor Contain mesh in the treatment of a patient requiring maxillary and mandibular horizontal ridge augmentation to enable implant placement. The patient underwent a previously unsuccessful corticocancellous bone graft at these sites. Multiple and contiguous sites in the maxilla and in the mandibular anterior, demonstrating advanced lateral ridge deficiencies, were managed using a tissue engineering approach as an alternative to autogenous bone harvesting. Four maxillary and three mandibular implants were placed 9 and 10 months, respectively, after tissue engineering reconstruction, and all were functioning successfully after 24 months of follow-up. Histomorphometric analysis of a bone core obtained at the time of the maxillary implant placement demonstrated a mean of 76.1% new vital bone formation, 22.2% marrow/cells, and 1.7% residual graft tissue. Tissue engineering for lateral ridge augmentation with combination therapy requires further research to determine predictability and limitations.