Deproteinized Bovine Bone Mineral or Autologous Bone at Dehiscence Type Defects at Implants Installed Immediately into Extraction Sockets: An Experimental Study in Dogs.

PURPOSE: The aim of this study was to evaluate bone regeneration at surgically created dehiscence buccal defects at implants placed immediately into extraction sockets (IPIES) of small dimensions filled with autogenous bone or deproteinized bovine bone mineral (DBBM) associated with a collagen membrane. MATERIALS AND METHODS: Eight Labrador dogs were used and implants were placed immediately into the extraction sockets of the second premolar. The buccal wall was subsequently removed to create a standardized defect, 4 mm wide coronally, 2 mm wide apically, and 6 mm high. Autogenous bone particles (AB) or DBBM granules were used to fill the defects. All surgical sites were subsequently covered by a resorbable collagen membrane and a non-submerged healing was allowed. After 4 months, the animals were euthanized and bone blocks harvested and processed for histomorphometric analysis. RESULTS: The bony crest at the buccal aspect (C) was located 2.3 ± 0.8 mm and 1.7 ± 0.7 mm apically to the implant shoulder (IS) at the AB and DBBM sites, respectively. The coronal levels of osseointegration at the buccal aspect (B) were located 2.7 ± 0.7 mm and 2.2 ± 1.0 mm apically to IS at the AB and DBBM sites, respectively. At the AB sites, the peri-implant mucosa was located 4.3 ± 0.9 mm, 4.7 ± 0.9 mm, and 2.0 ± 1.6 mm coronally to C, B, and IS, respectively. The corresponding values at the DBBM sites were 4.3 ± 0.6 mm, 4.8 ± 0.6 mm, and 2.5 ± 0.8 mm, respectively. No statistically significant differences were found. CONCLUSIONS: The treatment of surgically created buccal defects at IPIES sites using Bio-Oss® (Geistlich Biomaterials, Wolhusen, LU, Switzerland) or autogenous bone, concomitantly with a collagen membrane, engenders bone regeneration to a similar extent after 4 months of healing.

Bone Ceramic® at Implants Installed Immediately into Extraction Sockets in the Molar Region: An Experimental Study in Dogs.

PURPOSE: The aim of this paper was to study the healing of 1-1.4 mm wide buccal defects at implants placed immediately into extraction sockets (IPIES) filled with a mixture of synthetic hydroxyapatite (HA) 60% and beta-tricalciumphosphate (TCP) 40% or left with the clot alone and both covered with collagen membranes. MATERIAL AND METHODS: Eight Labrador dogs were used and implants were placed immediately into the extraction sockets of the first molar bilaterally. A mixture of synthetic HA 60% and beta-TCP 40% at the test or the clot alone at the control sites were used to fill the defects. All surgical sites were subsequently covered by a resorbable collagen membrane and a non-submerged healing was allowed. After 4 months, the animals were euthanized, biopsies harvested and processed for histomorphometric analysis. RESULTS: At the time of installation, residual buccal defects occurred that were 1.1 mm and 1.4 mm wide and 3 mm and 4 mm deep at the control and test sites, respectively. After 4 months of healing, the top of the bony crest and the coronal level of osseointegration were located respectively at 0.1 ± 1.8 mm and 1.5 ± 1.8 mm at the test, and 0.6 ± 1.6 mm and 1.2 ± 0.7 mm at the control sites apically to the implant shoulder. Bone-to-implant contact at the buccal aspect was 34.9 ± 25.9% and 36.4 ± 17.3% at the test and control sites, respectively. No statistically significant differences were found between test and control sites for any of the variables analyzed at the buccal aspects. CONCLUSIONS: The use of a mixture of synthetic HA 60% and beta-TCP 40% to fill residual buccal defects 1-1.4 mm wide at IPIES did not improve significantly the results of healing.

Influence analysis of cleft type and supernumerary teeth eruption in the prognosis of bone graft in patients with cleft palate.

OBJECTIVE: The aim of this study was to investigate the influence of cleft type and supernumerary tooth eruption on the treatment of palatal clefts with alveolar bone grafts. MATERIALS AND METHODS: In this article, medical records of 40 patients with palatal clefts and associated supernumerary teeth who were treated with alveolar bone grafting in the Hospital for Craniofacial Anomalies Rehabilitation were assessed. The patients were studied to assess the influence of supernumerary teeth and the cleft severity on the prognosis of the alveolar bone graft. RESULTS: Forty medical records were included in the assessment. When the teeth in the cleft had an anatomic shape close to canine, we called them precanine. When they were very small or malformed, we called them anomalous lateral incisors. The teeth studied showed good prognoses and were more expressive in the preforaminal clefts (87.5%) than in the transforaminal ones (62.5%). Moreover, the transforaminal clefts presented a higher percentage in satisfactory and poor prognoses (37.5%). The authors found that supernumerary teeth influenced the maintenance of alveolar bone graft height and that transforaminal clefts presented a worse prognosis than preforaminal clefts.

Evaluation of the presence of VEGF, BMP2 and CBFA1 proteins in autogenous bone graft: histometric and immunohistochemical analysis.

AIMS: The purpose of this study was to evaluate the expression of proteins that participate in the osteoinduction stage (VEGF, BMP2 and CBFA1) of the process of bone regeneration of defects created in rat calvariae and filled with autogenous bone block grafts. MATERIALS AND METHODS: 10 adult male rats (Rattus norvegicus albinus, Wistar) were used, who received two bone defects measuring 5 mm each in the calvariae. The bone defects constituted two experimental groups (n = 10): Control Group (CONT) (defects filled with a coagulum); Graft Group (GR) (defects filled with autogenous bone removed from the contralateral defect). The animals were submitted to euthanasia at 7 and 30 days post-operatively. RESULTS: Quantitative analysis demonstrated significantly greater bone formation in Group GR, but the presence of the studied proteins was significantly greater in the CONT Group in both time intervals of observation. CONCLUSION: It was not possible in this study in cortical bone block groups to detect the osteoinductive proteins in a significant amount during the repair process.

Influence of buccal bony crest width on marginal dimensions of peri-implant hard and soft tissues after implant installation. An experimental study in dogs.

AIM: To evaluate the influence of the width of the buccal bony wall on hard and soft tissue dimensions following implant installation. MATERIAL AND METHODS: Mandibular premolars and first molars of six Labrador dogs were extracted bilaterally. After 3 months of healing, two recipient sites, one on each side of the mandible, were prepared in such a way as to obtain a buccal bony ridge width of about 2 mm in the right (control) and 1 mm in the left sides (test), respectively. Implants were installed with the coronal margin flush with the buccal alveolar bony crest. Abutments were placed and the flaps were sutured to allow a non-submerged healing. After 3 months, the animals were euthanized and ground sections obtained. RESULTS: All implants were completely osseointegrated. In respect to the coronal rough margin of the implant, the most coronal bone-to-implant contact was apically located 1.04 ± 0.91 and 0.94 ± 0.87 mm at the test and control sites, respectively, whereas the top of the bony crest was located 0.30 ± 0.40 mm at the test and 0.57 ± 0.49 mm at the control sites. No statistically significant differences were found. A larger horizontal bone resorption, however, evaluated 1 mm apically to the rough margin, was found at the control (1.1 ± 0.7 mm) compared to the test (0.3 ± 0.3 mm) sites, the difference being statistically significant. A thin peri-implant mucosa (2.4-2.6 mm) was found at implant installation while, after 3 months of healing, a biological width of 3.90-4.40 mm was observed with no statistically significant differences between control and test sites. CONCLUSIONS: A width of the buccal bony wall of 1or 2 mm at implant sites yielded similar results after 3 months of healing in relation of hard tissue and soft tissues dimensions after implant installation.

Reconstrução imediata de diferentes defeitos peri-implantares em implantes pós-exodônticos: análise histomorfométrica em cães / Reconstruction of buccal different defects at implants placed immediately into extraction sockets: a histomorphometric analysis in dogs

Objetivo: A proposta deste estudo foi avaliar a regeneração óssea de defeitos criados cirurgicamente e naturais circunferenciais (gap) de implantes pósexodônticos. Materiais e método: Para este estudo foram utilizados 8 cães da raça labrador, nos quais foram instalados implantes imediatos (pós-exodônticos) nos alvéolos dos dentes P2 (2o pré-molar) e M1 (1o molar) inferiores bilaterais. Nos implantes da região dos 2º pré-molares bilaterais foram criados cirurgicamente defeitos peri-implantares vestibulares que foram preenchidos de um lado por osso autógeno – OA e do outro por osso bovino inorgânico Bio-Oss®- OB. Nos alvéolos correspondentes aos primeiros molares (M1) os implantes foram instalados e os gaps (defeitos naturais) existente entre a tábua óssea vestibular e o implante, foram preenchidos por Bone Ceramic® - (grupo BC) ou somente coágulo (grupo COA). Todos os sítios cirúrgicos foram posteriormente recobertos por membrana de colágeno reabsorvível (Biogide ®) e mantidos com cicatrizador. Após 4 meses de pós-operatório, os animais foram eutanasiados e os blocos ósseos processados laboratorialmente para análise histomorfométrica. Resultados: Os resultados obtidos nos implantes instalados na região do P2 mostraram que os valores do IS-C foram ligeiramente maior (2.3±0.8mm) no grupo OA, comparado ao grupo OB (1.7± 0.7 mm), enquanto o IS-B dos grupos OA e OB foram respectivamente de 2.7±0.7mm e 2.2±1.0 mm no lado vestibular e de 1.6±0.8mm e 0.8±0.5mm no lado lingual. As médias dos valores de PM-C, PM-B e PM-IS no grupo OA e OB foram respectivamente de 4.3±0.9mm, 4.7±0.9mm, 2.0±1.6mm e 4.3±0.6mm, 4.8±0.6mm, 2.5±0.8mm. A diferença estatística significativa foi observada somente na espessura da crista óssea vestibular de 2 a 5 mm em direção ao IS (“pescoço do implante”), incluindo o biomaterial (S-OCbt) que se apresentou maior no grupo OB. Nos implantes instalados na região do M1, o gap vestibular horizontal foi de 1.1 (COA) e 1.4 mm (BC) e vertical de 3 e...

Objective: The purpose of these studies were to evaluate bone regeneration at natural or surgically-created buccal defects at implants placed immediately into extraction sockets (IPIES). Material and methods: Eight Labrador dogswere used and implants were placed immediately into the extraction sockets of P2 (second premolar) and M1 (first molar), bilaterally. At P2, the buccal wall of the extraction sockets was removed bilaterally to create a standardized defect, 4 mm wide coronally, 2 mm wide apically, and 6 mm height. At P2 sites, Bio-Oss at the test (OB) or autogenous bone at the control (OA) sites were used to fill the defects. At M1 sites, Bone Ceramic ® at the test (BC) or the clot alone (COA) were used to fill the defects. All surgical sites were subsequently covered by a resorbable collagen membraneand a non-submerged healing was allowed. After 4 months the animals were euthanized, bone blocks harvested and processed for histomorphometric analysis. Results: at P2 sites, IS- C values were slightly higher (2.3±0.8mm) in the OA compared to the OB (1.7±0.7 mm). IS- B were 2.7 ± 0.7mm and 2.2 ± 1.0mm on the buccal side and 1.6 ± 0.8mm and 0.8 ± 0.5mm on the lingual side at OA and OB groups, respectively. The average values of PM- C , B - PM and PM -IS in OA and OB groups were 4.3 ± 0.9mm , 4.7 ± 0.9mm , 2.0 ± 1.6mm and 4.3 ± 0.6mm , 4.8 ± 0.6mm , 2.5 ± 0.8mm, respectively. A statistically significant difference was only observed in the thickness of the buccal bony crest at 2-5 mm apically to IS (the implant neck) when the biomaterial (S -OCbt) was included in the measurement, which appeared to be higher in the OB group. At M1 sites, at the time of installation, the horizontal buccal gap was 1.1 at the COA and 1.4 mm at the BC sites while the vertical remaining defect was 3 mm and 4 mm deep in the control and test sites, respectively. At the buccal aspect, IS-C was higher in the COA (0.6 ± 1.6mm) compared to the BC (0.1 ± 1.8mm) groups and IS- B was...

Reconstrução imediata de diferentes defeitos peri-implantares em implantes pós-exodônticos: análise histomorfométrica em cães / Reconstruction of buccal different defects at implants placed immediately into extraction sockets: a histomorphometric analysis in dogs

Objetivo: A proposta deste estudo foi avaliar a regeneração óssea de defeitos criados cirurgicamente e naturais circunferenciais (gap) de implantes pósexodônticos. Materiais e método: Para este estudo foram utilizados 8 cães da raça labrador, nos quais foram instalados implantes imediatos (pós-exodônticos) nos alvéolos dos dentes P2 (2o pré-molar) e M1 (1o molar) inferiores bilaterais. Nos implantes da região dos 2º pré-molares bilaterais foram criados cirurgicamente defeitos peri-implantares vestibulares que foram preenchidos de um lado por osso autógeno – OA e do outro por osso bovino inorgânico Bio-Oss®- OB. Nos alvéolos correspondentes aos primeiros molares (M1) os implantes foram instalados e os gaps (defeitos naturais) existente entre a tábua óssea vestibular e o implante, foram preenchidos por Bone Ceramic® - (grupo BC) ou somente coágulo (grupo COA). Todos os sítios cirúrgicos foram posteriormente recobertos por membrana de colágeno reabsorvível (Biogide ®) e mantidos com cicatrizador. Após 4 meses de pós-operatório, os animais foram eutanasiados e os blocos ósseos processados laboratorialmente para análise histomorfométrica. Resultados: Os resultados obtidos nos implantes instalados na região do P2 mostraram que os valores do IS-C foram ligeiramente maior (2.3±0.8mm) no grupo OA, comparado ao grupo OB (1.7± 0.7 mm), enquanto o IS-B dos grupos OA e OB foram respectivamente de 2.7±0.7mm e 2.2±1.0 mm no lado vestibular e de 1.6±0.8mm e 0.8±0.5mm no lado lingual. As médias dos valores de PM-C, PM-B e PM-IS no grupo OA e OB foram respectivamente de 4.3±0.9mm, 4.7±0.9mm, 2.0±1.6mm e 4.3±0.6mm, 4.8±0.6mm, 2.5±0.8mm. A diferença estatística significativa foi observada somente na espessura da crista óssea vestibular de 2 a 5 mm em direção ao IS (“pescoço do implante”), incluindo o biomaterial (S-OCbt) que se apresentou maior no grupo OB. Nos implantes instalados na região do M1, o gap vestibular horizontal foi de 1.1 (COA) e 1.4 mm (BC) e vertical de 3 e...

Objective: The purpose of these studies were to evaluate bone regeneration at natural or surgically-created buccal defects at implants placed immediately into extraction sockets (IPIES). Material and methods: Eight Labrador dogswere used and implants were placed immediately into the extraction sockets of P2 (second premolar) and M1 (first molar), bilaterally. At P2, the buccal wall of the extraction sockets was removed bilaterally to create a standardized defect, 4 mm wide coronally, 2 mm wide apically, and 6 mm height. At P2 sites, Bio-Oss at the test (OB) or autogenous bone at the control (OA) sites were used to fill the defects. At M1 sites, Bone Ceramic ® at the test (BC) or the clot alone (COA) were used to fill the defects. All surgical sites were subsequently covered by a resorbable collagen membraneand a non-submerged healing was allowed. After 4 months the animals were euthanized, bone blocks harvested and processed for histomorphometric analysis. Results: at P2 sites, IS- C values were slightly higher (2.3±0.8mm) in the OA compared to the OB (1.7±0.7 mm). IS- B were 2.7 ± 0.7mm and 2.2 ± 1.0mm on the buccal side and 1.6 ± 0.8mm and 0.8 ± 0.5mm on the lingual side at OA and OB groups, respectively. The average values of PM- C , B - PM and PM -IS in OA and OB groups were 4.3 ± 0.9mm , 4.7 ± 0.9mm , 2.0 ± 1.6mm and 4.3 ± 0.6mm , 4.8 ± 0.6mm , 2.5 ± 0.8mm, respectively. A statistically significant difference was only observed in the thickness of the buccal bony crest at 2-5 mm apically to IS (the implant neck) when the biomaterial (S -OCbt) was included in the measurement, which appeared to be higher in the OB group. At M1 sites, at the time of installation, the horizontal buccal gap was 1.1 at the COA and 1.4 mm at the BC sites while the vertical remaining defect was 3 mm and 4 mm deep in the control and test sites, respectively. At the buccal aspect, IS-C was higher in the COA (0.6 ± 1.6mm) compared to the BC (0.1 ± 1.8mm) groups and IS- B was...

Bone healing pattern in surgically created circumferential defects around submerged implants: an experimental study in dog.

OBJECTIVE: To describe the healing of marginal defects below or above 1 mm of dimension around submerged implants in a dog model. MATERIAL AND METHODS: In 12 Labrador dogs, all mandibular premolars and first molars were extracted bilaterally. After 3 months of healing, full-thickness flaps were elevated in the edentulous region of the right side of the mandible. Two recipient sites were prepared and the marginal 5 mm were widened to such an extent to obtain, after implant installation, a marginal gap of 0.5 mm at the mesial site (small defect) and of 1.25 mm at the distal site (large defect). Titanium healing caps were affixed to the implants and the flaps were sutured allowing a fully submerged healing. The experimental procedures were subsequently performed in the left side of the mandible. The timing of the experiments and sacrifices were planned in such a way to obtain biopsies representing the healing after 5, 10, 20 and 30 days. Ground sections were prepared and histomorphometrically analyzed. RESULTS: The filling of the defect with newly formed bone was incomplete after 1 month of healing in all specimens. Bone formation occurred from the base and the lateral walls of the defects. A larger volume of new bone was formed in the large compared with the small defects. Most of the new bone at the large defect was formed between the 10- and the 20-day period of healing. After 1 month of healing, the outline of the newly formed bone was, however, located at a similar distance from the implant surface (about 0.4 mm) at both defect types. Only minor newly formed bone in contact with the implant, starting from the base of the defects, was seen at the large defects (about 0.8 mm) while a larger amount was detected at the small defects (about 2.2 mm). CONCLUSION: Marginal defects around titanium implants appeared to regenerate in 20-30 days by means of a distance osteogenesis. The bone fill of the defects was, however, incomplete after 1 month.

Comparative analysis of 2-flap designs for extraction of mandibular third molar.

OBJECTIVE: The objective of the study was to analyze 2-flap designs for surgical extraction of third molar, evaluating the periodontal status of the second lower molar. STUDY DESIGN: Forty-five lower third molars were extracted from 24 patients. In 23 teeth, a vertical incision to the mandibular ramus was used (technique A), whereas 22 teeth were submitted to classic L-shaped flap (technique B) with controls at 60 and 90 days postoperatively. RESULTS: Pearson correlation coefficient analysis showed a significant correlation only between immediate preoperative probing depth variables from techniques A and B in the studied surfaces. Statistical significances in the preoperative (vestibular) and postoperative day 60 (distovestibular and vestibular) were noted. In contrast, Student t-test showed no statistical difference in probing depths between preoperative and postoperative values, as well as no statistically significant difference regarding the type of incision alone. CONCLUSIONS: Technique A allowed a less traumatic surgery, guaranteeing a more comfortable postoperative period.

Bone regeneration at implants placed into extraction sockets of maxillary incisors in dogs.

AIM: To compare the influence of autologous or deproteinized bovine bone mineral as grafting material on healing of buccal dehiscence defects at implants installed immediately into the maxillary second incisor extraction socket in dogs. MATERIAL AND METHODS: In the maxillary second incisor sockets of 12 Labrador dogs, implants were installed immediately following tooth extraction. A standardized buccal defect was created and autologous bone particles or deproteinized bovine bone mineral were used to fill the defects. A collagen membrane was placed to cover the graft material, and the flaps were sutured to fully submerge the experimental areas. Six animals were sacrificed after 2 months, and six after 4 months of healing. Ground sections were obtained for histological evaluation. RESULTS: After 2 months of healing, all implants were osseointegrated. All buccal dehiscence defects were completely filled after 2 months irrespective of the augmentation material (autologous bone or Bio-Oss(®)) applied. Bone-to-implant contact (BIC) on the denuded implant surfaces was within a normal range of 30-40%. However, the newly formed tissue at 2 months was partially resorbed (>50% of the area measurements) after 4 months. CONCLUSIONS: Applying either autologous bone or deproteinized bovine bone mineral to dehiscences at implants installed immediately into extraction sockets resulted in high degree of regeneration of the defects with satisfactory BIC on the denuded implant surface.

Uso de miniplaca e parafusos de titânio para correção ortodôntica de extrusão alveolar / Use of miniplates and titanium screws for orthodontic correction of alveolar extrusion

A extrusão de rebordos alveolares pode ocorrer em função da não reposição dos elementos dentários perdidos no arco oposto, isto pode dificultar a instalação de próteses de forma e contorno adequados. A correção destas extrusões pode se tornar de difícil execução, e, portanto, algumas formas de tratamento podem ser propostas como: o preparo e a restauração dos dentes por corte de parte das coroas com tratamento endodôntico subsequente quando necessário; o reposicionamento cirúrgico por osteotomia segmentar ou a intrusão ortodôntica realizada com o auxílio de dispositivos para ancoragem. O propósito deste relato é apresentar uma técnica cirúrgica de instalação destes dispositivos acessórios fundamentais na terapêutica proposta em um paciente que apresentou extrusão do rebordo alveolar maxilar esquerdo em função da não reabilitação protética após a perda dentária dos dentes inferiores ipsilateral, impossibilitando a confecção de próteses com altura adequada. Após planejamento ortodôntico-cirúrgico foi realizado a instalação de uma miniplaca de titânio que foi fixada por meio de dois parafusos do sistema 1.0 mm (sistema de miniplacas e parafusos bucomaxilofaciais), por vestibular, e dois parafusos do mesmo sistema, por palatino. Estes dispositivos foram utilizados como ancoragem ortodôntica para intrusão do rebordo alveolar. Ao final da intrusão foi possível a confecção das próteses, visando à reabilitação do paciente. A técnica cirúrgica de instalação destes dispositivos mostrou-se de fácil realização e de prognóstico previsível, possibilitando a reabilitação protética de forma desejada.

The extrusion of alveolar ridges may occur depending on the replacement of items not lost dental arch opposite, this may hinder the establishment of joint shape and contour suitable. The correction of these extrusions can be difficult to implement, and therefore some forms of treatment may be proposed as: the preparation and restoration of teeth by cutting some of the crowns with subsequent endodontic treatment when necessary, the repositioning by surgical osteotomy segment or orthodontic intrusion performed with the aid of devices for anchoring. The purpose of this report is to present the surgical technique of installing these devices in the proposed therapeutic essential accessories in a patient who had extrusion of the left maxillary alveolar ridge in terms of non-rehabilitation dental prosthesis after loss of lower teeth on the same side, making the impossible prostheses with adequate height. After orthodontic-surgical planning was the installation of a titanium miniplate has been fixed by two bolts of the system 1 (system miniplates and screws bucomaxilofaciais) by vestibular, and two screws in the same system, for palatal. These devices were used as anchors for orthodontic intrusion of the alveolar ridge. At the end of the intrusion could be the making of dentures, to the rehabilitation of the patient. The surgical technique of installation of these devices are shown to be of easy implementation and prognosis predictable, allowing the rehabilitation prosthetics so desired.

Bone regeneration in surgically created defects filled with autogenous bone: an epifluorescence microscopy analysis in rats.

UNLABELLED: Although the search for the ideal bone substitute has been the focus of a large number of studies, autogenous bone is still the gold standard for the filling of defects caused by pathologies and traumas, and mainly, for alveolar ridge reconstruction, allowing the titanium implants installation. OBJECTIVES: The aim of this study was to evaluate the dynamics of autogenous bone graft incorporation process to surgically created defects in rat calvaria, using epifluorescence microscopy. MATERIAL AND METHODS: Five adult male rats weighing 200-300 g were used. The animals received two 5-mm-diameter bone defects bilaterally in each parietal bone with a trephine bur under general anesthesia. Two groups of defects were formed: a control group (n=5), in which the defects were filled with blood clot, and a graft group (n=5), in which the defects were filled with autogenous bone block, removed from the contralateral defect. The fluorochromes calcein and alizarin were applied at the 7th and 30th postoperative days, respectively. The animals were killed at 35 days. RESULTS: The mineralization process was more intense in the graft group (32.09%) and occurred mainly between 7 and 30 days, the period labeled by calcein (24.66%). CONCLUSIONS: The fluorochromes showed to be appropriate to label mineralization areas. The interfacial areas between fluorochrome labels are important sources of information about the bone regeneration dynamics.

Bone regeneration in surgically created defects filled with autogenous bone: an epifluorescence microscopy analysis in rats

Although the search for the ideal bone substitute has been the focus of a large number of studies, autogenous bone is still the gold standard for the filling of defects caused by pathologies and traumas, and mainly, for alveolar ridge reconstruction, allowing the titanium implants installation. OBJECTIVES: The aim of this study was to evaluate the dynamics of autogenous bone graft incorporation process to surgically created defects in rat calvaria, using epifluorescence microscopy. MATERIAL AND METHODS: Five adult male rats weighing 200-300 g were used. The animals received two 5-mm-diameter bone defects bilaterally in each parietal bone with a trephine bur under general anesthesia. Two groups of defects were formed: a control group (n=5), in which the defects were filled with blood clot, and a graft group (n=5), in which the defects were filled with autogenous bone block, removed from the contralateral defect. The fluorochromes calcein and alizarin were applied at the 7th and 30th postoperative days, respectively. The animals were killed at 35 days. RESULTS: The mineralization process was more intense in the graft group (32.09 percent) and occurred mainly between 7 and 30 days, the period labeled by calcein (24.66 percent). CONCLUSIONS: The fluorochromes showed to be appropriate to label mineralization areas. The interfacial areas between fluorochrome labels are important sources of information about the bone regeneration dynamics.

Vantagens e limitações da técnica de frenulectomia à laser Er: Yag / Advantages and limitations of the technique of frenulectomy to laser Er: Yag

Os frênulos labiais são inserções de tecido conjuntivo fibroso e têm como função limitar os movimentos do lábio, promovendo sua estabilização e impedindo a excessiva exposição da mucosa gengival na área de sua inserção. Entretanto, os frênulos podem exercer funções adversas, sendo indicada sua remoção cirúrgica por motivos periodontais, ortodônticos, protéticos e estéticos. Este trabalho tem como objetivo discutir a frenulectomia com uso do laser Er: Yag, comparando suas vantagens e limitações em relação às técnicas de frenulectomias convencionais.

The labial frenulum are insertions of fibrous conjunctive tissue and have function of a labial frenulum is to limit movements of the lip, promoting stabilization and to impede the excessive exhibition of the gingival mucosa in the area attachment. However, the frenulum can exercise adverse functions, being indicated its surgical removal by periodontal, orthodontics, prosthetic and aesthetic reasons. This paper aim objective to discuss the frenulectomy with use of the laser Er:Yag, comparing its advantages and limitations in relation to the conventional frenulectomy techniques.

Alterações dimensionais de modelos obtidos de alginatos, com diferentes técnicas de manipulação, com e sem armazenamento em cuba umidificadora / Dimensional changes of obtained casts with alginates, with different manipulation techniques, with and without storage in vat umidificadora

Neste trabalho, o objetivo foi estudar as alterações dimensionais ocorridas em modelos de gesso, obtidos por meio de moldes com um alginato do tipo siliconizado e um convencional, manipulados com as técnicas: convencional, manual em saco plástico e na palma da mão (adensado), estando armazenados ou não em cuba umidificadora, até que ocorressem a presa do gesso. Foram feitos 60 moldes com alginato, de uma arcada inferior em plástico. Obtidos os moldes, nestes foram vertidos gesso pedra tipo III, conseguindo os modelos de gesso, metade destes (30) foram colocados dentro da cuba umidificadora, permanecendo fechada por 60 minutos e os demais (30) foram mantidos à temperatura ambiente, até a presa final. Após a separação molde/modelo, as medidas foram obtidas por meio de microscópio de mensuração, sobre os modelos de gesso, comparando-as com a da arcada plástica (controle). Os dados foram comparados por meio de análise de variância e do teste de Tukey. Os resultados mostraram-se significantes a 5 por cento (p<0,05), na região intercaninos para os fatores analisados materiais e técnicas, e na região intermolares para os fatores materiais, técnicas e meios de armazenamento. Concluiu-se que: região de caninos: para o alginato, o Jeltrate foi melhor que o Orthoprint; quanto às técnicas a convencional e saco plástico mostraram-se melhores que a adensada. Na região de molares: para o alginato, Orthoprint foi melhor que o Jeltrate; a técnica convencional foi pior que a do saco plástico e adensada; para o meio de armazenamento, o uso da cuba Wet Box mostrou ser melhor, que só no meio ambiente