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1.
Polymers (Basel) ; 15(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36679277

RESUMO

The purpose of this study was to evaluate the color changes of feldspathic ceramics CEREC Blocs (Dentsply Sirona, Milford, DE, USA) when cemented with different luting agents, while varying the ceramic thickness. Seventy ceramic discs of feldspathic ceramic (A2 shade) were obtained with 0.5 and 0.8 mm thicknesses. Seventy composite discs (A3 shade) 1 mm in thickness were used as substrates. After being polished and conditioned, the ceramic and composite discs were cemented with different resin cements and a flowable composite: Variolink® Esthetic Light, Neutral and Warm (Ivoclar Vivadent, Schaan, Liechtenstein); RelyXTM Veneer B0.5, Translucent and A3 Opaque/yellow shades (3M Oral Care, St. Paul, MN, USA); G-aenial® Universal Flow A2 (GC Europe, Leuven, Belgium). Color difference (ΔE) was determined using a spectrophotometer. A two-way ANOVA and multiple comparisons were performed using the Bonferroni method with a 95% confidence interval. Variolink® Neutral showed the highest ΔE (15.12 ± 0.71) and RelyXTM Veneer A3 the lowest value (1.59 ± 0.33). There are no statistically significant differences between the two ceramic thicknesses for Variolink® Light (p = 0.230) and RelyXTM Veneer B0.5 (p = 0.318) cements. The feldspathic ceramic final color is influenced by the cement used and the ceramic thickness. The use of different cements in a thin ceramic has a clinically significant impact on the final esthetic result.

3.
Ann Maxillofac Surg ; 11(1): 49-57, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34522654

RESUMO

INTRODUCTION: Maxillary distraction may be used to treat severe maxillary hypoplasia in cleft lip and palate (CLP) patients. Three-dimensional (3D) planning has been shown to increase the accuracy of distraction and reduce operative time and complications. The aim of the study was to measure the accuracy of internal maxillary distraction after 3D planning in CLP patients, to add evidence to validate the virtual osteotomy and distraction procedure. MATERIALS AND METHODS: Eleven CLP patients with severe maxillary hypoplasia underwent maxillary distraction using internal distractors. Virtual planning was used to design the osteotomies, the distractor position, and the distraction vector. Cutting and positioning guides transferred this information to the surgical procedure. Four to six month postoperative computed tomography-scan was done before distractor removal; anatomical reference points were compared to the virtual planning to determine accuracy. RESULTS: A high accuracy (point dislocation <1.5 mm) was found in 90% of the points of the surface of the maxilla; the majority of the zygomatic screws were placed within a distance of 0.8-1 mm from their planned position. DISCUSSION: The high accuracy achieved through virtual planning promotes optimal distractor placement; a customized distraction vector has a direct effect on the final position of the maxilla.

4.
J Clin Exp Dent ; 11(5): e400, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31275510

RESUMO

In relation to the article of the Journal of Clinical and Experimental Dentistry "Calvo-Guirado JL, Aguilar-Salvatierra A, Guardia J, Delgado-Ruiz R, Ramírez-Fernández MP, Pérez-Sánchez C, Gómez-Moreno G. Evaluation of periimplant bone neoformation using different scanning electron microscope methods for measuring BIC. A dog study. J Clin Exp Dent. 2012 Feb 1;4(1):e8-e13", the authors have used three figures that are the same as those published in three different publications (J Pineal Res 2010; COIR 2010; COIR 2012). The copyright of the mentioned publications was consequently not respected. Retraction of the article is therefore decided.

5.
J Clin Med ; 8(5)2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-31067735

RESUMO

The aim of this experimental animal study was to assess guided bone regeneration (GBR) and implant stability (ISQ) around two dental implants with different macrogeometries. Forty eight dental implants were placed within six Beagle dogs. The implants were divided into two groups (n = 24 per group): G1 group implants presented semi-conical macrogeometry, a low apical self-tapping portion, and an external hexagonal connection (whereby the cervical portion was bigger than the implant body). G2 group implants presented parallel walls macrogeometry, a strong apical self-tapping portion, and an external hexagonal connection (with the cervical portion parallel to the implant body). Buccal (mouth-related) defects of 2 mm (c2 condition) and 5 mm (c3 condition) were created. For the control condition with no defect (c1), implants were installed at crestal bone level. Eight implants in each group were installed under each condition. The implant stability quotient (ISQ) was measured immediately after implant placement, and on the day of sacrifice (3 months after the implant placement). Histological and histomorphometric procedures and analysis were performed to assess all samples, measuring crestal bone loss (CBL) and bone-to-implant contact (BIC). The data obtained were compared with statistical significance set at p < 0.05. The ISQ results showed a similar evolution between the groups at the two evaluation times, although higher values were found in the G1 group under all conditions. Within the limitations of this animal study, it may be concluded that implant macrogeometry is an important factor influencing guided bone regeneration in buccal defects. Group G1 showed better buccal bone regeneration (CBL) and BIC % at 3 months follow up, also parallel collar design can stimulate bone regeneration more than divergent collar design implants. The apical portion of the implant, with a stronger self-tapping feature, may provide better initial stability, even in the presence of a bone defect in the buccal area.

6.
Dent J (Basel) ; 6(2)2018 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-29734774

RESUMO

Objectives: The objective of this study was to evaluate new bone formation derived from freshly crushed extracted teeth, grafted immediately in post-extraction sites in an animal model, compared with sites without graft filling, evaluated at 30 and 90 days. Material and Methods: The bilateral premolars P2, P3, P4 and the first mandibular molar were extracted atraumatically from six Beagle dogs. The clean, dry teeth were ground immediately using the Smart Dentin Grinder. The tooth particles obtained were subsequently sieved through a special sorting filter into two compartments; the upper container isolating particles over 1200 μm, the lower container isolated particles over 300 μm. The crushed teeth were grafted into the post-extraction sockets at P3, P4 and M1 (test group) (larger and smaller post-extraction alveoli), while P2 sites were left unfilled and acted as a control group. Tissue healing and bone formation were evaluated by histological and histomorphometric analysis after 30 and 90 days. Results: At 30 days, test site bone formation was greater in the test group than the control group (p < 0.05); less immature bone was observed in the test group (25.71%) than the control group (55.98%). At 90 days, significant differences in bone formation were found with more in the test group than the control group. No significant differences were found in new bone formation when comparing the small and large alveoli post-extraction sites. Conclusions: Tooth particles extracted from dog’s teeth, grafted immediately after extractions can be considered a suitable biomaterial for socket preservation.

7.
Clin Oral Implants Res ; 29(7): 772-778, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27041138

RESUMO

OBJECTIVE: This study aimed to measure the influence of drill length and irrigation system on heat production during osteotomy preparation for dental implants using bovine bone rib as experimental model. MATERIALS AND METHODS: Three groups were created: Group 1: drilling with three consecutive burs with double irrigation (internal and external) for a 4.0 mm conical implant; and Group 2 and Group 3: drilling with three consecutive burs with external irrigation for a 4.1 mm cylindrical implant and for a 4.3 mm conical implant, respectively. Four lengths were tested: 10, 12, 14 and 16 mm; in site prepared on bovine ribs using a surgical unit linked to a testing device, to standardize and simulate implant drilling procedures. Bone temperature variations were recorded using three thermocouples in different positions as of the crestal bone: 2 mm, position (p1); 7 mm, position 2 (p2); and 12 mm, position 3 (p3). RESULTS: The highest temperature changes were invariably recorded during the process of withdrawal. Significantly lower temperature changes (P < 0.02) could be recorded at maximum drilling depths during the shearing process regardless of drilling depth or irrigation method. Double irrigation was associated with significantly lower temperatures compared with external irrigation by the use of implant drills (P < 0.01). CONCLUSIONS: Within the limitations of this ex vivo study was possible concluded that the use a double irrigation system in multiple conventional drill for osteotomy can decrease the heat generation when increase the drill length.


Assuntos
Implantação Dentária Endóssea , Animais , Bovinos , Implantação Dentária Endóssea/efeitos adversos , Implantação Dentária Endóssea/instrumentação , Implantação Dentária Endóssea/métodos , Temperatura Alta , Osteotomia/efeitos adversos , Osteotomia/instrumentação , Osteotomia/métodos , Costelas/cirurgia , Irrigação Terapêutica
8.
Clin Oral Implants Res ; 29(6): 635-643, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26744262

RESUMO

OBJECTIVE: To evaluate marginal bone loss over 5 years around microthreaded implants placed in the maxillary anterior/esthetic zone and immediate restored with non-occlusal loading. MATERIALS AND METHODS: Seventy-one implants (with microthreads up to the platform-rough surface body and neck, internal connection and platform switching) were placed in healed bone in the maxillary arches of 30 men and 23 women (mean age 37.85 ± 7.09 years, range 27-60). All subjects had at least 3 mm of soft tissue to allow the establishment of adequate biologic width and to reduce bone resorption. Each patient received a provisional restoration immediately after implant placement with slight occlusal contact. Mesial and distal bone height was evaluated using digital radiography on the day following implant placement (baseline) and after 1, 2, 3, 4 and 5 years. Primary stability was measured with resonance frequency analysis. RESULTS: No implants failed, resulting in a cumulative survival rate of 100% after 3 years. Marginal bone loss from implant collar to bone crest measured at baseline (peri-implant bone defect at the fresh extraction socket) and after 5 years was 0.90 mm ± 0.26 mm. Mesial and distal site crestal bone loss ranged from 3.42 ± 1.2 mm at baseline to 3.51 ± 1.5 mm after 5 years and from 3.38 ± 0.9 mm at baseline to 3.49 ± 0.9 mm after 5 years, respectively (P = 0.086). CONCLUSIONS: The results of this study showed limited implant crestal bone loss 0.90 mm ± 0.26 mm and 100% of implant survival rate at 5-year follow-up of immediate restored implants with rough surface neck and microthreads.


Assuntos
Perda do Osso Alveolar/diagnóstico por imagem , Implantação Dentária Endóssea/efeitos adversos , Implantes Dentários/efeitos adversos , Adulto , Perda do Osso Alveolar/etiologia , Perda do Osso Alveolar/patologia , Implantação Dentária Endóssea/instrumentação , Implantação Dentária Endóssea/métodos , Restauração Dentária Permanente , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia Dentária
9.
Materials (Basel) ; 10(5)2017 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-28772900

RESUMO

Some studies have demonstrated that in vivo degradation processes are influenced by the material's physico-chemical properties. The present study compares two hydroxyapatites manufactured on an industrial scale, deproteinized at low and high temperatures, and how physico-chemical properties can influence the mineral degradation process of material performance in bone biopsies retrieved six months after maxillary sinus augmentation. Residual biomaterial particles were examined by field scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) to determine the composition and degree of degradation of the bone graft substitute material. According to the EDX analysis, the Ca/P ratio significantly lowered in the residual biomaterial (1.08 ± 0.32) compared to the initial composition (2.22 ± 0.08) for the low-temperature sintered group, which also presented high porosity, low crystallinity, low density, a large surface area, poor stability, and a high resorption rate compared to the high-temperature sintered material. This demonstrates that variations in the physico-chemical properties of bone substitute material clearly influence the degradation process. Further studies are needed to determine whether the resorption of deproteinized bone particles proceeds slowly enough to allow sufficient time for bone maturation to occur.

10.
Materials (Basel) ; 10(6)2017 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-28772984

RESUMO

Detailed information about graft material characteristic is crucial to evaluate their clinical outcomes. The present study evaluates the physico-chemical characteristics of two xenografts manufactured on an industrial scale deproteinized at different temperatures (non-sintered and sintered) in accordance with a protocol previously used in sinus lift procedures. It compares how the physico-chemical properties influence the material's performance in vivo by a histomorphometric study in retrieved bone biopsies following maxillary sinus augmentation in 10 clinical cases. An X-ray diffraction analysis revealed the typical structure of hydroxyapatite (HA) for both materials. Both xenografts were porous and exhibited intraparticle pores. Strong differences were observed in terms of porosity, crystallinity, and calcium/phosphate. Histomorphometric measurements on the bone biopsies showed statistically significant differences. The physic-chemical assessment of both xenografts, made in accordance with the protocol developed on an industrial scale, confirmed that these products present excellent biocompatibilitity, with similar characteristics to natural bone. The sintered HA xenografts exhibited greater osteoconductivity, but were not completely resorbable (30.80 ± 0.88% residual material). The non-sintered HA xenografts induced about 25.92 ± 1.61% of new bone and a high level of degradation after six months of implantation. Differences in the physico-chemical characteristics found between the two HA xenografts determined a different behavior for this material.

11.
Materials (Basel) ; 10(6)2017 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-28773005

RESUMO

The aim of the present study was to monitor implant stability after sinus floor elevation with two biomaterials during the first six months of healing by resonance frequency analysis (RFA), and how physico-chemical properties affect the implant stability quotient (ISQ) at the placement and healing sites. Bilateral maxillary sinus augmentation was performed in 10 patients in a split-mouth design using a bobine HA (BBM) as a control and porcine HA (PBM). Six months after sinus lifting, 60 implants were placed in the posterior maxilla. The ISQ was recorded on the day of surgery from RFA at T1 (baseline), T2 (three months), and T3 (six months). Statistically significant differences were found in the ISQ values during the evaluation period. The ISQ (baseline) was 63.8 ± 2.97 for BBM and 62.6 ± 2.11 for PBM. The ISQ (T2) was ~73.5 ± 4.21 and 67 ± 4.99, respectively. The ISQ (T3) was ~74.65 ± 2.93 and 72.9 ± 2.63, respectively. All of the used HAs provide osseointegration and statistical increases in the ISQ at baseline, T2 and T3 (follow-up), respectively. The BBM, sintered at high temperature with high crystallinity and low porosity, presented higher stability, which demonstrates that variations in the physico-chemical properties of a bone substitute material clearly influence implant stability.

12.
Clin Implant Dent Relat Res ; 19(1): 123-130, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27189627

RESUMO

PURPOSE: The present study aimed to measure the implant stability quotient (ISQ) values at three different time points after surgical procedures and crestal bone behavior in multiple implants (two or more) installed simultaneously with the bone splitting technique. MATERIALS AND METHODS: For this study, 45 patients with different edentulous areas in the maxilla were selected, and a total of 114 dental implants were installed. Implant stability was measured by resonance frequency analysis immediately following implant placement to assess immediate stability (time 1) and stability at 90 days (time 2), and 150 days (time 3). Crestal bone height was measured in peri-apical radiographs at 90 and 150 days after implantation in relation to each implant shoulder, given that the implants were installed at the level of the crestal bone. RESULTS: Six implants were not osseointegrated. Overall, the means and standard deviations of the ISQ values were 60.3 ± 4.94 (95% confidence interval [CI], 44-69) at baseline, 66.6 ± 5.28 (95% CI, 49-75) at 90 days, and 72.1 ± 4.28 (95% CI, 59-79) at 150 days (p < 0.0001). The mean marginal bone loss of the implants was 1.11 ± 0.61 mm on the mesial side and 1.17 ± 0.61 mm on the distal side at time 2, and 1.73 ± 0.68 mm on the mesial side and 1.79 ± 0.70 mm on the distal side at time 3. A strong positive correlation between implant stability and bone loss was detected (p < 0.0001). CONCLUSIONS: Within the limits of this study, the bone splitting technique with simultaneous implant installation exhibited a good success rate with respect to the osseointegration index but requires attention with respect to crestal bone behavior.


Assuntos
Implantação Dentária Endóssea/métodos , Planejamento de Prótese Dentária , Retenção em Prótese Dentária , Osteotomia Maxilar/métodos , Osseointegração/fisiologia , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/etiologia , Adulto , Projeto do Implante Dentário-Pivô , Feminino , Seguimentos , Humanos , Carga Imediata em Implante Dentário , Masculino , Maxila/diagnóstico por imagem , Maxila/cirurgia , Pessoa de Meia-Idade , Boca Edêntula/diagnóstico por imagem , Boca Edêntula/cirurgia , Análise de Frequência de Ressonância
13.
Ann Anat ; 208: 109-115, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27565228

RESUMO

The aim of this study was to evaluate the influence of the residual root and peri implant bone dimensions on the clinical success of the socket shield technique. Thirty-six dental implants were installed in 6 dogs. The clinical crowns of teeth P3, P4 and M1 were beheaded. Afterwards, the roots were worn down 2-3mm in apical direction until they were located at crestal level. Posterior implant beds were prepared in the center of the roots passing by 3mm apically forming 6 groups in accordance to the remaining root thickness. Radiography of the crestal bone level was performed on day 0 and after 12 weeks. Histomorphometric analyses of the specimens were carried out to measure the crestal bone level, the bone to implant contact and the buccal and lingual bone thickness at the implant shoulder portion. Correlations between groups were analyzed through nonparametric Friedman test, statistical significance was set as p<0.05. All 36 implants were osseointegrated, but 3 samples showed a clinical inflammatory reaction and some radicular fragments presented a small resorption process. On the buccal and lingual side, the radicular fragment was attached to the buccal bone plate by a physiologic periodontal ligament. In the areas where there was space between the implant and the fragment, newly formed bone was demonstrated directly on the implant surface. Within the limitations of an animal pilot study, root-T belt technique may be beneficial in preserving and protecting the bundle bone and preservation of soft tissues. If the thickness of the buccal bone is 3mm, and the thickness of the remaining root fragment is 2mm, the socket shield technique is more predictable and the bone contours can be maintained.


Assuntos
Técnica para Retentor Intrarradicular/instrumentação , Extração Dentária/instrumentação , Raiz Dentária/citologia , Raiz Dentária/cirurgia , Alvéolo Dental/citologia , Alvéolo Dental/cirurgia , Animais , Interface Osso-Implante/anatomia & histologia , Implantes Dentários para Um Único Dente , Cães , Carga Imediata em Implante Dentário/instrumentação , Carga Imediata em Implante Dentário/métodos , Órgãos em Risco/anatomia & histologia , Extração Dentária/métodos , Resultado do Tratamento
14.
Ann Anat ; 206: 104-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27045596

RESUMO

The aim of this study is to assess the effectiveness of using non-titanium abutments for better establishment of peri-implant biological width and to assess the stability of the soft tissue. Forty-eight tapered dental titanium implants with internal connection of 3.5mm in diameter and 10mm length were implanted in post extraction alveoli of 6 dogs. Twenty-four abutments made in a reinforced polyetheretherketone (PEEK) formed the test group, and 24 titanium abutments, the control group. The groups were randomized. Histological, histomorphometric, ISQ and radiological analyses were performed. Greatest differences (control group vs. test group) were found at PM-Lc (Mucosa to lingual bone contact) (2.91±0.03 vs. 3.71±0.18), and to PM Lingual-IS (2.65±0.43 vs. 3.57±0.38). Reinforced PEEK constitutes an effective alternative to conventional titanium abutments, given its high rate of biocompatibility, preservation of bone height and soft tissue stability.


Assuntos
Interface Osso-Implante/patologia , Dente Suporte/efeitos adversos , Cetonas/efeitos adversos , Peri-Implantite/etiologia , Polietilenoglicóis/efeitos adversos , Alvéolo Dental/patologia , Animais , Benzofenonas , Materiais Biocompatíveis/efeitos adversos , Implantes Dentários para Um Único Dente/efeitos adversos , Materiais Dentários/efeitos adversos , Cães , Masculino , Teste de Materiais , Osseointegração , Peri-Implantite/patologia , Polímeros , Titânio/efeitos adversos , Alvéolo Dental/efeitos dos fármacos , Resultado do Tratamento
15.
Clin Oral Implants Res ; 27(4): 497-504, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25664845

RESUMO

BACKGROUND: Narrow-diameter implants provide an alternative to the horizontal augmentation techniques situations severe bone atrophy. Lack of bone width and interdental space has been regarded as an encumbrance in the case selection for prosthetic rehabilitation using dental implants. OBJECTIVE: The aim of the study was to evaluate bone-to-implant contact and marginal bone loss of two different narrow implants in resorbed ridges at different crestal positions. MATERIAL AND METHODS: 48 Bredent Narrow(®) implants (24 MiniSky(®) and NarowSky(®) ) were placed at crestal and subcrestal levels in healing bone of atrophic alveolar ridge of 6 American foxhounds. Histological and histomorphometric analyses of osseointegration were carried out at 4 and 8 weeks. RESULTS: Modeling in the marginal defect region was accompanied by marked decreases in the dimensions of both the buccal and the more lingual bone walls. Relative to BIC, significant differences were found in favor of subcrestal group, for both Narrow Sky and MiniSky. Linear measurements showed to be slightly high in the crestal group. With significant differences for PM-IS (peri-implant mucosa to implant shoulder) and IS-BC (implant shoulder to buccal bone crest). CONCLUSIONS: Within the limitations of animal study, it can be stated that the NarrowSky(test group) crestal and subcrestal implants showed less crestal bone resorption, higher ISQ values and most BIC at 4 and 8 weeks of evaluation compared with MiniSky implants (control group). The design of the implants plays an important role in peri-implant mucosa and crestal bone maintenance at 8-week follow-up period.


Assuntos
Perda do Osso Alveolar/patologia , Processo Alveolar/patologia , Implantes Dentários , Osseointegração , Animais , Remodelação Óssea , Cães
16.
Artigo em Inglês | MEDLINE | ID: mdl-26249361

RESUMO

Retraction: Maté Sánchez de Val JE , Calvo Guirado JL , Ramírez Fernández MP , Delgado Ruiz RA , Mazón P, De Aza PN . In vivo behavior of hydroxyapatite/ß­TCP /collagen scaffold in animal model. Histological, histomorphometrical, radiological, and SEM analysis at 15, 30, and 60 days. Clin Oral Impl Res . The above article, published online on August 7, 2015, in Wiley Online Library (wileyonlinelibrary.com) has been retracted by agreement between the journal editor­in­chief, L Heitz­Mayfield, and John Wiley & Sons Ltd. The retraction has been agreed due to image discrepancies resulting in unreliable data. It has not been possible to prove the validity of the images. Images in Figure 4 have been used in other publications representing different time points and materials. Images within Figure 4 have been manipulated to represent different time points and materials. Reference Maté Sánchez de Val JE , Calvo Guirado JL , Ramírez Fernández MP , Delgado Ruiz RA , Mazón P, De Aza PN . In vivo behavior of hydroxyapatite/ß­TCP /collagen scaffold in animal model. Histological, histomorphometrical, radiological, and SEM analysis at 15, 30, and 60 days. Clin Oral Impl Res . https://doi.org/10.1111/clr.12656

17.
Clin Implant Dent Relat Res ; 17(4): 667-80, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24118965

RESUMO

PURPOSE: To describe contact, thickness, density, and orientation of connective tissue fibers around healing abutments of different geometries by means of a new method using coordinates. MATERIALS AND METHODS: Following the bilateral extraction of mandibular premolars (P2, P3, and P4) from six fox hound dogs and a 2-month healing period, 36 titanium implants were inserted, onto which two groups of healing abutments of different geometry were screwed: Group A (concave abutments) and Group B (wider healing abutment). After 3 months the animals were sacrificed and samples extracted containing each implant and surrounding soft and hard tissues. Histological analysis was performed without decalcifying the samples by means of circularly polarized light under optical microscope and a system of vertical and horizontal coordinates across all the connective tissue in an area delimited by the implant/abutment, epithelium, and bone tissue. RESULTS: In no case had the connective tissue formed a connection to the healing abutment/implant in the internal zone; a space of 35 ± 10 µm separated the connective tissue fibers from the healing abutment surface. The total thickness of connective tissue in the horizontal direction was significantly greater in the medial zone in Group B than in Group A (p < .05). The orientation of the fibers varied according to the coordinate area so that internal coordinates showed a higher percentage of parallel fibers in Group A (p < .05) and a higher percentage of oblique fibers in Group B (p < .05); medial coordinates showed more oblique fibers (p < .05); and the area of external coordinates showed the highest percentage of perpendicular fibers (p < .05). The fiber density was higher in the basal and medial areas (p < .05). CONCLUSIONS: Abutment geometry influences the orientation of collagen fibers; therefore, an abutment with a profile wider than the implant platform favors oblique and perpendicular orientation of collagen fibers and greater connective tissue thickness.


Assuntos
Dente Suporte , Implantes Dentários , Microscopia de Polarização/métodos , Animais , Cães , Humanos , Projetos Piloto
18.
Int J Oral Sci ; 6(2): 105-10, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24556954

RESUMO

Recently, porous titanium granules (PTGs) have been indicated for the preservation of the dimensions of post-extraction sockets, as a filler in sinus lift procedures and for the treatment of peri-implant and periodontal defects, based on the osteoconductivity and dimensional stability of the titanium granules. However, there is a lack of information regarding the use of this material in larger defects and in conjunction with membranes. The objective of this study is to test the behavior of PTGs used to fill critical size defects in rabbit tibiae, with and without membranes. Critical defects were created in both tibiae of rabbits, divided randomly into three groups: Group A (defect filled with PTG), Group B (defect filled with PTG+collagen membrane) and a control group (empty defect). After six weeks, histomorphometric analysis was performed. The results showed more defect closures at the cortical area (87.37%±2.2%) and more bone formation at the marrow area (57.6%±1.3%) in Group B, in comparison with the other groups (P<0.05); the use of membranes improved the material stability expressed as more percentages of the original material when membranes were used (P<0.05). Finally, inflammatory reactions were observed when the granules were not protected by membranes. In spite of the limitations of this animal study, it may be concluded that PTG particles are osteoconductive and allow bone growth. The PTG particles must be covered by a membrane, especially when grafting larger defects, in order to control particle migration, promote clot stabilization and separate the PTG graft from undesired soft tissue cells.


Assuntos
Membranas Artificiais , Tíbia/anormalidades , Titânio/química , Animais , Masculino , Coelhos
19.
Clin Implant Dent Relat Res ; 16(6): 856-72, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23560416

RESUMO

PURPOSE: The study aims to assess the total soft tissue (ST) width, crestal bone level (CBL), bone-to-implant contact (BIC), and bone density (BD) for zirconia implants textured with microgrooved surfaces and immediately loaded. MATERIALS AND METHODS: This study included 51 implants; one implant from each study group was retained for surface characterization. The 48 remaining implants were inserted randomly in premolar areas of both sides of the healed edentulous lower jaws of foxhound dogs. They were divided into three groups of 16: control (titanium); test A (zirconia), and test B (microgrooved zirconia). The implants were splinted and covered with an acrylic bridge. A split-mouth design was used and immediate occlusal loading was applied on one side, while the other side did not have occlusal contact. ST, CBL, BIC, and BD were evaluated after 3 months. The effects of immediate loading on these parameters were analyzed. RESULTS: All the implants were osseointegrated. ST was established at 3 months with mean values of 2.9 ± 0.4 mm for all groups. No differences were appreciated between loaded and unloaded sides regarding ST (p > .05). CBL showed a mean of 1.2 ± 0.3 mm for all groups without differences between loaded and unloaded sides (p > .05). BIC percentages were significantly higher for loaded all-microgrooved implants (p < .05). BD percentages were higher in areas close to all-microgrooved implants (p < .05) and significantly higher for loaded implants than unloaded. CONCLUSIONS: Within the limitations of the present study, it may be concluded that for zirconia dental implants with microgrooved surfaces and immediate loading, the thickness of STs remains stable resulting in 3 mm mean biologic width, that crestal bone preservation is related to insertion depth, and that higher BIC percentages and increased BD around implants microgrooved over the entire intraosseous area may be expected at 3 months following implant insertion and immediate loading.


Assuntos
Densidade Óssea/fisiologia , Interface Osso-Implante/anatomia & histologia , Implantes Dentários , Materiais Dentários/química , Carga Imediata em Implante Dentário/métodos , Mandíbula/anatomia & histologia , Periodonto/anatomia & histologia , Zircônio/química , Condicionamento Ácido do Dente/métodos , Óxido de Alumínio/química , Processo Alveolar/anatomia & histologia , Animais , Força de Mordida , Corrosão Dentária/métodos , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Prótese Parcial , Cães , Lasers , Distribuição Aleatória , Propriedades de Superfície , Fatores de Tempo , Titânio/química
20.
Gerodontology ; 31(4): 274-80, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23294350

RESUMO

OBJECTIVE: The aim of this study was to evaluate the clinical efficacy of a topical sialogogue spray containing 1% malic acid for elderly people affected by xerostomia. MATERIAL AND METHODS: This research took the form of a double-blind, randomized clinical trial. Forty-one individuals (mean age: 78.7 years) with xerostomia were divided into two groups: for the first 'intervention group' (21 subjects) a topical sialogogue spray (1% malic acid) was applied, while for the second 'control group' (20 subjects), a placebo spray was applied; for both groups, the sprays were applied on demand during 2 weeks. The Xerostomia Inventory (XI) was used to evaluate xerostomia levels before and after product/placebo application. Unstimulated and stimulated salivary flows rates, before and after spray application, were measured. RESULTS: XI scores decreased significantly (clinically meaningful) from 36.4 ± 7.3 points to 29.1 ± 7.1 (p < 0.05) with an XI difference of 7.2 ± 6.1, after the combination among 1% malic acid with xylitol and fluoride application. After 2 weeks of 1% malic acid application, unstimulated and stimulated salivary flows rates increased significantly (p < 0.05). CONCLUSION: A topical sialogogue spray containing 1% malic acid improved xerostomia in an elderly population and increased unstimulated and stimulated salivary flows rates.


Assuntos
Malatos/uso terapêutico , Saliva Artificial/uso terapêutico , Xerostomia/tratamento farmacológico , Administração Oral , Aerossóis , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Fluoretos/administração & dosagem , Fluoretos/uso terapêutico , Humanos , Malatos/administração & dosagem , Masculino , Placebos , Saliva/efeitos dos fármacos , Saliva/metabolismo , Saliva Artificial/administração & dosagem , Taxa Secretória/efeitos dos fármacos , Resultado do Tratamento , Xerostomia/classificação , Xilitol/administração & dosagem , Xilitol/uso terapêutico
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