Use of buccal fat pad-derived stem cells cultured on bioceramics for repair of critical-sized mandibular defects in healthy and osteoporotic rats.

OBJECTIVE: To compare new bone formation in mandibular symphysis critical-sized bone defects (CSBDs) in healthy and osteoporotic rats filled with bioceramics (BCs) with or without buccal fat pad mesenchymal stem cells (BFPSCs). MATERIALS AND METHODS: Thirty-two adult female Sprague-Dawley rats were randomized to two groups (n = 16 per group): group 1 healthy and group 2 osteoporotic (with bilateral ovariectomy). The central portion of the rat mandibular symphysis was used as a physiological CSBD. In each group, eight defects were filled with BC (hydroxyapatite 60% and ß-tricalcium phosphate 40%) alone and eight with BFPSCs cultured on BC. The animals were sacrificed at 4 and 8 weeks, and the mandibles were processed for micro-computed tomography to analyze radiological union and bone mineral density (BMD); histological analysis of the bone union; and immunohistochemical analysis, which included immunoreactivity of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2). RESULTS: In both groups, CSBDs filled with BC + BFPSCs showed greater radiological bone union, BMD and histological bone union, and more VEGF and BMP-2 positivity, compared with CSBDs treated with BC alone at 4 and 8 weeks. CONCLUSIONS: The application of BFPSCs cultured on BCs improves bone regeneration in CSBDs compared with BCs alone in healthy and osteoporotic rats. CLINICAL RELEVANCE: Our results may aid bone regeneration of maxillofacial CSBDs of both healthy and osteoporotic patients, but further studies are necessary.

Effects of diabetes on oxidative stress, periodontal ligament fiber orientation, and matrix metalloproteinase 8 and 9 expressions during orthodontic tooth movement.

OBJECTIVES: To evaluate the influence of diabetes on oxidative stress, periodontal ligament (PDL) orientation, and matrix metalloproteinase (MMP) 8 and 9 expressions during orthodontic tooth movement in a rat model. MATERIALS AND METHODS: An orthodontic appliance was placed in 60 Sprague-Dawley rats divided into three groups: normoglycemics (n = 20) and two streptozotocin-induced diabetic groups, one untreated (n = 20) and one insulin-treated (n = 20). At 24, 48, and 72 h and 1 week, rats were sacrificed. At each time point, myeloperoxidase (MPO) and malondialdehyde (MDA) were quantified by spectrophotometry, tooth movement was evaluated by micro-CT analysis, and hematoxylin and eosin staining was used to evaluate PDL fiber orientation and immunohistochemistry staining with semi-quantitative H-score analysis of MMP-8 and MMP-9 was performed.. RESULTS: At 24 h, MPO activity was significantly higher in untreated-diabetics than normoglycemics. At 24 and 48 h, the MDA level in untreated-diabetic rats was significantly higher than in normoglycemics and insulin-treated animals. At 72 h and 1 week, PDL fibers were oriented significantly more irregularly in untreated-diabetics than in normoglycemics. At all time points, MMP-8 and MMP-9 expressions were significantly higher in both diabetic groups than in the normoglycemic group. After the second day, tooth movement was significantly greater in untreated-diabetics than in the insulin-treated and normoglycemic groups. CONCLUSIONS: Mechanical stress in untreated-diabetic rats produces more inflammatory response, oxidative stress, tooth movement, PDL disorganization, and MMP-8 and MMP-9 expressions than among normoglycemics. Insulin reverses these effects, favoring the reorganization of periodontal ligament. CLINICAL RELEVANCE: Our results suggest that the application of orthodontic force in diabetic patients would increase inflammation and delay periodontal restructuring. Insulin would partly reverse this situation although glycemic decompensation episodes may occur. For these reasons, the periods between fixed orthodontic appliance activations should be of sufficient duration to allow adequate tissue recovery.

Bone union formation in the rat mandibular symphysis using hydroxyapatite with or without simvastatin: effects on healthy, diabetic, and osteoporotic rats.

OBJECTIVE: The objective is to compare new bone formation in critical defects in healthy, diabetic, and osteoporotic rats filled with hydroxyapatite (HA) alone and HA combined with simvastatin (SV). MATERIALS AND METHODS: A total of 48 adult female Sprague-Dawley rats were randomized into three groups (n = 16 per group): Group, 1 healthy; Group 2, diabetics; and Group 3, osteoporotics. Streptozotocin was used to induce type 1 diabetes in Group 2, while bilateral ovariectomy was used to induce osteoporosis in Group 3. The central portion of the rat mandibular symphysis was used as a physiological critical bone defect. In each group, eight defects were filled with HA alone and eight with HA combined with SV. The animals were sacrificed at 4 and 8 weeks, and the mandibles were processed for micro-computed tomography to analyze radiological union and bone mineral density (BMD); histological analysis of the bone union; and immunohistochemical analysis, which included immunoreactivity of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2). RESULTS: In all groups (healthy, diabetics, and osteoporotics), the defects filled with HA + SV presented greater radiological bone union, BMD, histological bone union, and more VEGF and BMP-2 positivity, in comparison with bone defects treated with HA alone. CONCLUSIONS: Combined application of HA and SV improves bone regeneration in mandibular critical bone defects compared with application of HA alone in healthy, diabetic, and osteoporotic rats. CLINICAL RELEVANCE: This study might help to patients with osteoporosis or uncontrolled diabetes type 1, but future studies should be done.

Bone regeneration in critical-sized mandibular symphysis defects using bioceramics with or without bone marrow mesenchymal stem cells in healthy, diabetic, osteoporotic, and diabetic-osteoporotic rats.

OBJECTIVES: To compare new bone formation in mandibular critical-sized bone defects (CSBDs) in healthy, diabetic, osteoporotic, and diabetic-osteoporotic rats filled with bioceramics (BCs) with or without bone marrow mesenchymal stem cells (BMSCs). METHODS: A total of 64 adult female Sprague-Dawley rats were randomized into four groups (n = 16 per group): Group 1 healthy, Group 2 diabetic, Group 3 osteoporotic, and Group 4 diabetic-osteoporotic rats. Streptozotocin was used to induce type 1 diabetes in Group 2 and 4, while bilateral ovariectomy was used to induce osteoporosis in Group 3 and 4. The central portion of the rat mandibular symphysis was used as a physiological CSBD. In each group, eight defects were filled with BC (hydroxypatatite 60% and ß-tricalcium phosphate 40%) alone and eight with BMSCs cultured on BC. The animals were sacrificed at 4 and 8 weeks, and the mandibles were processed for micro-computed tomography to analyze radiological union and bone mineral density (BMD); histological analysis of the bone union; and immunohistochemical analysis, which included immunoreactivity of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2). RESULTS: In all groups (healthy, diabetics, osteoporotics, and diabetics-osteoporotics), the CSBDs filled with BC + BMSCs showed greater radiological bone union, BMD, histological bone union, and more VEGF and BMP-2 positivity, in comparison with CSBDs treated with BC alone (at 4 and 8 weeks). CONCLUSIONS: Application of BMSCs cultured on BCs improves bone regeneration in CSBDs compared with application of BCs alone in healthy, diabetic, osteoporotic, and diabetic-osteoporotic rats.

Morphometric evaluation of the sphenopalatine foramen for endonasal surgery.

OBJECTIVE: Ligation of the sphenopalatine artery is used to treat severe nasal haemorrhage. Despite the high rates of success reported, errors and complications may occur in locating the sphenopalatine foramen (SPF) through which the vasculonervous structures penetrate the nasal cavity. Thus, the objective of this study was to investigate the numerical variation of the SPF, its relation to the ethmoid bone crista of the palatine bone in the lateral nasal wall, its distance from the anterior nasal spine and the angle between this distance and the anterior nasal floor. DESIGN: Anatomical study. SETTING: Regional tertiary reference center. MATERIAL AND INTERVENTIONS: Fifty-four hemiskulls were submitted to anatomical study and measurements were made on more than 12 dissected hemiskulls using the Image Tool 3.0 software. RESULTS: The SPF was single in 87% of the specimens, and more than one orifice was present in 13%. In most specimens it was possible to establish a relation with the ethmoid crista, which is a surgical reference for the SPF location. The mean values of the measurements were significantly higher in the hemifaces than in the hemiskulls, ranging from 54 to 63 mm, and angulation ranged from 20 to 32 degrees. CONCLUSIONS: The study demonstrated that in most specimens studied the SPF was single and located in the superior nasal meatus. The distances measured suggest that these values can be used as distance references for the use of the endoscope for ligation or endonasal cauterization of the branches of the sphenopalatine artery, preventing possible errors and complications.

Results of reaugmentation with MISTI prostheses after failure of smooth silicone prostheses.

In 1988 and 1989, we replaced smooth silicone double-lumen implants with Molecular Impact Surface Textured Implants (MISTIs) in 28 of our patients. Of these, 20 had experienced recurrent capsular contracture and sought an alternative prosthesis that would provide long-term relief from this problem, and 8 simply wanted larger prostheses. Among the reaugmentation patients who had experienced recurrent contractures, 4 have had problems with the texturized implants; 1 developed an infection, and 3 developed unilateral fibrosis within weeks of surgery. The infection was resolved with antibiotics, and the fibrosis was resolved with capsulectomy, biweekly methylprednisolone irrigation in the surgical pocket, and lenticular suction drainage over a 3-week period. After a 2-year follow-up, these 4 problematic patients have remained soft and asymptomatic following their treatment, and the remaining 16 patients have remained soft and asymptomatic since their surgery.

Finding of a bullet in the cervical column of a body hit by a train.

This case is about the finding of a body of an unidentified male of approximately 70 years of age who was hit by a train. During the carrying out of the corresponding autopsy and after the radiological tests for posterior odontological identification, a foreign body of a cylindrical-cone shape, identical to that of a bullet, was found lodged between the first and second cervical vertebrae. During dissection of the neck, a bullet was found. When the ballistic test was carried out, it was ascertained that the bullet was from a cartridge of 7.92 by 57-mm Mauser caliber, manufactured in Spain in 1936. This ammunition corresponds to that used during the Civil War in Spain (1936-1939). After the identification of the body, it was proved that the bullet was the result of a war wound. However, the victim had been unaware of the existence of the bullet, which had remained in his body for 50 years.

Histoenzymology and morphometry of the masticatory muscles of tufted capuchin monkey (Cebus apella Linnaeus, 1758).

Samples of the anterior and posterior regions of the masseter and temporal muscles and of the anterior belly of the digastric muscle of 4 adult male tufted capuchin monkeys (Cebus apella) were removed and stained with HE and submitted to the m-ATPase reaction (with alkaline and acid preincubation) and to the NADH-TR and SDH reactions. The results of the histoenzymologic reactions were similar, except for acid reversal which did not occur in fibers of the fast glycolytic (FG) type in the mandibular locomotor muscles. FG fibers had a larger area and were more frequent in all regions studied. No significant differences in frequency or area of each fiber type were detected, considering the anterior and posterior regions of the masseter and temporal muscles. The frequency of fibers of the fast oxidative glycolytic (FOG) and slow oxidative (SO) types and of FOG area differed significantly between the anterior belly of the digastric muscle and the mandibular locomotor muscle. The predominance of fast twitch (FG and FOG) fibers and the multipenniform and bipenniform internal architecture of the masseter and temporal muscles, respectively, are characteristics that permit the powerful bite typical of tufted capuchin monkeys.

Anatomy of the maxillary artery into the pterygomaxillopalatine fossa.

The trajectory and ramifications of the maxillary artery near to and in the pterygomaxillopalatine (pterygopalatine, pterygomaxillar) fossa are reported by the authors through transmaxillary and endonasal microdissections of thirty heads from Brazilian males. They observed that always close to the maxillary tuberosity, the maxillary artery reaches the medial wall of the fossa, after tortuous and complex trajectory as a network around the nervous ramifications. They found on average of 11 branches from the maxillary artery in the fossa. The posterior superior alveolar and descending palatine arteries were observed as the largest branchs from the maxillary artery near to and in the fossa, while the thinnest branche was the artery of the round canal. The infraorbital and posterior superior alveolar arteries were verify as a common trunk in 27 cases (45.00%). The dehiscence of the posterior wall of the maxillary sinus, produced by the infraorbital artery was observed in 1 case (1.66%). In 53 cases (88.33%) the maxillary artery bifurcated in sphenopalatine and descending palatine branches, while in 7 cases (11.66%) was present the trifurcation. The sphenopalatine bifurcation in septal and posterior lateral nasal arteries inside the fossa was found in 54 cases (90.00%), and the ramification of the descending palatine artery in lesser palatine branches before of the penetration in the respectives canals, was present in all the cases.

Histological study on the prenatal development of the cheek-teeth of rabbits (Oryctolagus cuniculus).

The prenatal development of cheek-teeth of rabbits was studied by histological methods. Females from 15 to 30 days of gestation were sacrificed and their fetuses were collected and decapitated. The heads were fixed in buffered neutral formalin and paraffin embedded. Sagittal and frontal sections of 7 mu were obtained and stained with hematoxylin-eosin. The first tooth-germs observed were the m3 and m3, in the animal of 16 days of fetal life. One day after the m4 and m4 are observed in the bud stage. The last teeth to initiate development in the fetal rabbits are the M3 and M3 at 30 days. Only the m3, m4, m3 and m4 start cementogenesis in the prenatal stage.

A no bleed implant.

Breast implants have evolved from the original saline-filled, smooth-surfaced silicone rubber bag to silicone gel-filled smooth-walled sacs to a combination of a silicone gel-filled bag within a saline-filled sac, and, most recently, a reversed, double-lumen implant with a saline bag inside of a gel-filled bag. Texture-surfaced implants were first used in 1970 when the standard silicone gel-filled implant was covered with a polyurethane foam. Because of concerns about the degradation products of this foam, they were removed from the market in 1991. In 1975 double-lumen silicone textured implants were developed, followed by silicone gel-filled textured implants. In 1990 a new radiolucent, biocompatible gel was produced that reduced the problem of radioopacity of silicone implants. Because of the gel's sufficiently low coefficient of friction, leakage caused by fold flaw fracture may also be decreased. We present a case where this new biocompatible gel implant was repositioned after four months. The resulting scar capsule in this soft breast was thin [< 0.002 cm (0.008 in.)] and evenly textured as a mirror image of the textured silicone surface. Scanning electron microscopy and x-ray defraction spectrophotometry revealed no silicone bleed.

Fiber types distribution in the digastric muscle of tufted capuchin monkey (Cebus apella).

Fiber types distribution in the digastric muscle of tufted capuchin monkey was studied by means of NADH-TR, myosin-ATPase, after alkaline and acid preincubations and SDH histochemical reactions. Three different types of fibers were found presenting an equal distribution. The percentage and types of fibers were as follow: 18.2% SO (Slow Oxidative), 38.4% FOG (Fast Oxidative Glycolytic) and 43.4% FG (Fast Glycolytic). FG fibers revealed the largest area. The relatively high concentration of fast twitch (81.2%) seems to indicate this muscle is involved with the acceleration and fast speed of jaw movements. Aerobic metabolism represented by SO + FOG fibers (56.6%) suggests that this muscle possesses an additional role than that related to the lowering of the jaw.

Histological study on the postnatal development and sequence of eruption of the mandibular cheek-teeth of rabbits (Oryctolagus cuniculus).

The postnatal development and sequence of eruption of mandibular cheek teeth of rabbits were studied by histological methods. Hemi-mandibles were dissected and sectioned in longitudinal sections of 7 mu and stained with hematoxylin-eosin and Masson's trichrome. The presence of two mandibular deciduous molars which are replaced by corresponding premolars and of three mandibular permanent monofisary molars was confirmed. Eruption of deciduous molars of the mandible begins at 4 days after birth and of the mandibular permanent molars at 9 days, while that of mandibular premolars occurs at 23 days, replacing the mandibular deciduous molars which have exfoliated. At 32 days all the mandibular permanent cheek-teeth are erupted. At birth the mandibular deciduous molars are completely developed and at 4 days their root resorption is initiated. At the first day P3 is in the bell stage and the P4 has begun dentinogenesis. In M1 and M2 amelogenesis is observed.

Histological study on the postnatal development and sequence of eruption of the maxillary cheek-teeth of rabbits (Oryctolagus cuniculus).

The development and sequence of eruption of the maxillary cheek-teeth of rabbits were studied by histological methods. The presence of three deciduous molars which were replaced by correspondent premolars and of three permanent molars without predecessors was confirmed. The eruption of the maxillary deciduous molars was shown to begin at 4 days postnatally and that of the permanent molar at 9 days, while the eruption of the premolars occurs from 24 days on, replacing the deciduous molars which are exfoliated. The last tooth to erupt is the M3. At 32 days all the permanent cheek-teeth are erupted. The deciduous molars are completely developed at birth, root resorption starting at 4 days. On the first day the premolars are in the bell stage and in the M1 and M2 amelogenesis is taking place. After 27 days the development of the permanent maxillary cheek-teeth is completed. Dentinogenesis, amelogenesis and cementogenesis were observed in all of them.

Contribuicao ao estudo do nervo maxilar da fossa pterigopalatina. / Maxillary nerve of the pterygopalatine fossa

O conteudo nervoso da fossa pterigopalatina foi estudado pelos autores atraves da microdisseccao em 20 hemi-cabecas, com acesso pelas vias endonasal e transmaxilar. Neste trabalho inicial foi realizado o estudo sistematico do nervo maxilar e de sua ramificacao no interior da fossa, desde a emergencia atraves do forame redondo ate a penetracao do canal infra-orbital. Intensa e complexa ramificacao foi observada, com a emissao de ramos em todas as direcoes, alem de numerosas anastomoses em suas trajetorias. Puderam ser identificados diversos ramos, como orbitarios, ganglionares, palatinos, antrais e alveolares superiores posteriores e medios

Variacao anatomica do plexo infra-orbital. Relato de um caso. / Anatomical variation of the infra-orbital plexus. Report of a case

Os autores relatam um caso de variacao anatomica do plexo infra-orbital em uma cirurgia do seio maxilar. Ressaltam a possibilidade do encontro de estruturas vizinhas ao antro dentro desta, e comentam a anatomia e variacoes do plexo infra-orbital. Salientam a necessidade de um exame pre-operatorio detalhado da cavidade sinusal, antes de um procedimento cirurgico a este nivel. O intuito e o de preservar estruturas anatomicas que porventura estejam no interior do seio maxilar