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1.
Neurol Int ; 16(1): 113-125, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38251055

RESUMO

(1) Background: Considering that the specialty literature supplies only general data about the variability of the cervical branch of the facial nerve, this study aimed to determine this branch's variation and individual peculiarities depending on the nerve branching pattern and anthropometric type of the head. (2) Methods: The study was conducted on 75 hemifaces of adult formalized cadavers. Ahead of anatomical dissection, each head was measured to establish the anthropometric type, according to Franco and colleagues. The branching patterns were then distributed according to the Davis classification. (3) Results: The number of cervical branches (CB) of the facial nerve varied from one to five branches, with the following rate: 1 CB (61.3%), 2 CB (28%), 3 CB (6.7%), 4 CB (2.7%), and 5 CB (1.3%). Seven branching patterns of the facial nerve were revealed: Type I in 18.7%, Type II in 14.7%, Type III in 20%, Type IV in 14.6%, Type V in 5.3%, Type VI in 18.7%, and Type NI in 8% (bizarre types). According to the branching pattern, the mean numbers of the cervical branches were as follows: Type I-1.6 ± 1.02; Type II-1.4 ± 0.50; Type III-1.4 ± 0.50; Type IV-1.4 ± 0.67; Type V-2.0 ± 1.41; Type VI-1.8 ± 1.12; and Type-NI-1.8 ± 0.75; p = 0.599. According to the anthropometric type of the head, the mean number of CB in the mesocephalic type (MCT) was 1.5 ± 0.82, in the dolichocephalic type (DCT), 1.7 ± 0.87, and in the brachycephalic type, (BCT) 1.8 ± 1.04; p = 0.668. (4) Conclusions: The cervical branch of the facial nerve varies depending on the facial nerve branching pattern and the anthropometric type of the head. The highest degree of variation was characteristic of BCT and Type V and the lowest, of MCT and Types II, III, and IV.

2.
Biomedicines ; 11(2)2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36830902

RESUMO

Cancer is a global medical problem and, despite research efforts in the field of tumor treatment, there is currently a shortage of specific anticancer drugs. Most anticancer drugs show significant side effects. The liver is the organ that has central functions in drug metabolism, being a major target of the harmful action of anticancer compounds. In this context, it is essential to evaluate the cytotoxic effects of potential anticancer substances. Therefore, hepatotoxicity and hepatocyte viability were determined in vitro to evaluate the action of seven new local thiosemicarbazide coordination compounds (CCT) on normal liver cells. Doxorubicin was used as a reference substance. The control group consisted of hepatocytes not exposed to CCT action. The cell viability of hepatocytes treated with CCT decreased significantly by 5-12% compared to the control, but was statistically significantly higher by 5-14% compared to doxorubicin, except after CMD-8 and CMT-67 influence, when it does not change. Thus, new local CCT had a selective effect on hepatocytes in vitro and were less hepatotoxic compared to doxorubicin, which may be the basis for further study of its potential in anticancer drugs.

3.
Biomedicines ; 10(5)2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35625680

RESUMO

This study compared the osseointegration of acid-etched, ultrahydrophilic, micro- and nanostructured implant surfaces (ANU) with non-ultra-hydrophilic, microstructured (SA) and non-ultrahydrophilic, micro- and nanostructured implant surfaces (AN) in vivo. Fifty-four implants (n = 18 per group) were bilaterally inserted into the proximal tibia of New Zealand rabbits (n = 27). After 1, 2, and 4 weeks, bone-implant contact (BIC, %) in the cortical (cBIC) and spongious bone (sBIC), bone chamber ingrowth (BChI, %), and the supra-crestal, subperiosteal amount of newly formed bone, called percentage of linear bone fill (PLF, %), were analyzed. After one week, cBIC was significantly higher for AN and ANU when compared to SA (p = 0.01 and p = 0.005). PLF was significantly increased for ANU when compared to AN and SA (p = 0.022 and p = 0.025). After 2 weeks, cBIC was significantly higher in SA when compared to AN (p = 0.039) and after 4 weeks, no significant differences in any of the measured parameters were found anymore. Ultrahydrophilic implants initially improved osseointegration when compared to their non-ultrahydrophilic counterparts. In accordance, ultrahydrophilic implants might be appropriate in cases with a necessity for an accelerated and improved osseointegration, such as in critical size alveolar defects or an affected bone turnover.

4.
Clin Exp Dent Res ; 8(3): 757-762, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35543493

RESUMO

OBJECTIVES: While various approaches are available for tooth whitening, the basic concept employs the use of peroxides in the form of gels, which are applied to tooth surfaces. Previous studies have shown that reactive oxygen species acting as potent disinfectants can be produced using boron-doped diamond (BDD) electrodes for the electrolysis of water. With these electrodes being applicable, for example, for endodontic treatment, it was the goal of this pilot study to use such electrodes for tooth whitening. MATERIAL AND METHODS: Two groups (n = 10) of intact clinical crowns were obtained by horizontally cutting off roots of extracted human teeth. The crowns were either bleached by applying a commercially available agent based on 40% hydrogen peroxide or were immersed in saline undergoing electrolysis with BDD electrodes. Whitening of specimens was judged on standardized photographs by examiners with three different levels of experience. Statistical analysis was based on Gwet's AC2 coefficient with quadratic weights, Shapiro-Wilk tests, and two-way analysis of variance of aligned rank transformed data (level of significance set at α = .05). RESULTS: Levels of reliability ranging from fair to substantial were recorded for single persons while the level of reliability ranged between fair and moderate for groups of raters. The level of experience had no significant effect on the ratings (p = .2500). The bleaching method had a significant effect on ratings (p = .0005) with BDD electrodes showing less effect. CONCLUSIONS: Bleaching by applying BDD electrodes was possible, but was not as effective as the use of commercially available in-office whitening gel. A potential explanation may be seen in different concentrations of reactive oxygen species.


Assuntos
Clareamento Dental , Boro , Eletrodos , Géis , Humanos , Projetos Piloto , Espécies Reativas de Oxigênio , Reprodutibilidade dos Testes , Clareamento Dental/métodos
5.
Microorganisms ; 10(4)2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35456832

RESUMO

While numerous approaches have meanwhile been described, sufficient disinfection of root canals is still challenging, mostly due to limited access and the porous structure of dentin. Instead of using different rinsing solutions and activated irrigation, the electrolysis of saline using boron-doped diamond (BDD) electrodes thereby producing reactive oxygen species may be an alternative approach. In a first step, experiments using extracted human teeth incubated with multispecies bacterial biofilm were conducted. The charge quantities required for electrochemical disinfection of root canals were determined, which were subsequently applied in an animal trial using an intraoral canine model. It could be shown that also under realistic clinical conditions, predictable disinfection of root canals could be achieved using BDD electrodes. The parameters required are in the range of 5.5 to 7.0 V and 9 to 38 mA, applied for 2.5 to 6.0 min with approximately 5 to 8 mL of saline. The direct generation of disinfective agents inside the root canal seems to be advantageous especially in situations with compromised access and limited canal sizes. The biologic effect with respect to the host reaction on BDD-mediated disinfection is yet to be examined.

6.
Head Face Med ; 16(1): 35, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33287844

RESUMO

BACKGROUND: The aim was to compare early biochemical and histological osseous healing of chronic mandibular defects regenerated with bovine bone substitute with and without collagen membrane in vivo. METHODS: Eight weeks after formation of a lateral full-thickness perforating bone defect in the mandible of 40 rabbits, bovine bone substitute with ("+";n = 20) and without ("-";n = 20) collagen membrane was applied. Blood and bone was collected 24, 72 h, 7, 14 and 21 days after surgery. Total acid phosphatase, bone acid phosphatase, total alkaline phosphatase and bone alkaline phosphatase activities were compared between groups. Formation of new bone was quantified histologically for all time points. RESULTS: Twenty-four hours after surgery, bone alkaline phosphatase was significantly elevated in "+" group when compared to "-" (p=0.012). After 72 hours, all bone turnover markers except for total acid phosphatase (p=0.078) where significantly elevated in "+" (all p < 0.05). Fourteen days after surgery, the significant highest values for all bone turnover markers were detected in "-" (all p < 0.05). A significant difference in favor of group "-" could also be detected after 3 weeks in terms of both acid phosphatases (p < 0.05). In histology, no significant differences could be detected. CONCLUSION: Bone regeneration with bovine bone substitute material and collagen membrane shows a significantly earlier bone remodeling activity but does not seem to influence formation of new bone in histological samples.


Assuntos
Remodelação Óssea , Substitutos Ósseos , Animais , Regeneração Óssea , Bovinos , Colágeno , Membranas , Coelhos
7.
Int J Oral Maxillofac Implants ; 35(2): 313-319, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32142568

RESUMO

PURPOSE: Bone regeneration procedures are often evaluated based on biologic aspects only. As regenerated bone also has to ensure primary implant stability, the goal of this study was to determine the mechanical quality of regenerated bone. MATERIALS AND METHODS: Six adult minipigs were allocated for this experiment with four mandibular study sites each established following tooth removal. Two different types of bovine bone mineral as well as autogenous bone were used for augmenting three-walled defects, while native bone served as the control. Implants were placed after 12, 18, and 24 weeks of healing, and bone quality was determined using intraoperative compressive testing (BoneProbe), insertion torque measurements, and resonance frequency analysis. The mandibles were then harvested for determining bone mineral density (BMD) and bone-to-implant contact (BIC). Statistical analysis was based on two-way analysis of variance of aligned rank transformed data and Spearman's rank correlation tests (α = .05). RESULTS: The effects of the factors healing time and material on the parameters tested were too small to be significant (P ranging from .34 to .98). Weak correlations were observed for implant insertion torque with BoneProbe measurements in the cortical (0.481; P = .032) and in the trabecular area (0.639; P = .002). BoneProbe measurements in the trabecular part and in the cortical part also correlated with each other (0.477; P = .035). CONCLUSION: While differences may exist between bone regenerated using different biomaterials with respect to biologic behavior, differences in the mechanical properties determining primary implant stability seem to be minor. Implant insertion torque measurements appear to be a reliable tool for determining bone quality if only one specific implant type is considered.


Assuntos
Implantação Dentária Endóssea , Implantes Dentários , Animais , Densidade Óssea , Bovinos , Mandíbula/cirurgia , Torque
8.
Eur Surg Res ; 61(6): 177-187, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33601367

RESUMO

INTRODUCTION: We aimed to compare implant osseointegration with calcium phosphate (CaP) surfaces and rough subtractive-treated sandblasted/acid etched surfaces (SA) in an in vivo minipig mandible model. MATERIALS AND METHODS: A total of 36 cylindrical press-fit implants with two different surfaces (CaP, n = 18; SA, n = 18) were inserted bilaterally into the mandible of 9 adult female minipigs. After 2, 4, and 8 weeks, we analyzed the cortical bone-to-implant contact (cBIC; %) and area coverage of bone-to-implant contact within representative bone chambers (aBIC; %). RESULTS: After 2 weeks, CaP implants showed no significant increase in cBIC and aBIC compared to SA (cBIC: mean 38 ± 5 vs. 16 ± 11%; aBIC: mean 21 ± 1 vs. 6 ± 9%). Two CaP implants failed to achieve osseointegration. After 4 weeks, no statistical difference between CaP and SA was seen for cBIC (mean 54 ± 15 vs. 43 ± 16%) and aBIC (mean 43 ± 28 vs. 32 ± 6). However, we excluded two implants in each group due to failure of osseointegration. After 8 weeks, we observed no significant intergroup differences (cBIC: 18 ± 9 vs. 18 ± 20%; aBIC: 13 ± 8 vs. 16 ± 9%). Again, three CaP implants and two SA implants had to be excluded due to failure of osseointegration. CONCLUSION: Due to multiple implant losses, we cannot recommend the oral mandibular minipig in vivo model for future endosseous implant research. Considering the higher rate of osseointegration failure, CaP coatings may provide an alternative to common subtractive implant surface modifications in the early phase post-insertion.


Assuntos
Fosfatos de Cálcio , Implantação Dentária Endóssea , Implantes Dentários , Mandíbula/cirurgia , Titânio , Animais , Feminino , Modelos Animais , Osseointegração , Suínos , Porco Miniatura
9.
Clin Exp Dent Res ; 5(6): 594-600, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31890296

RESUMO

Objectives: Bone density, surgical protocol, and implant design are the major determinants of primary stability. The goal of this animal trial was to investigate potential correlations of intraoperative bone density testing with clinical and histologic parameters of primary implant stability. Material and methods: Following extractions of all mandibular premolars and subsequent healing, four implants each were placed in a total of four minipigs. Bone density was determined by applying intraoperative compressive tests using a device named BoneProbe whereas measurements of implant insertion torque and resonance frequency analysis were used for evaluating implant stability. Bone mineral density (BMD) and bone to implant contact were quantified after harvesting mandibular block sections. Spearman rank correlation tests were performed for evaluating correlations (α = .05). Results: Due to variation in clinical measurements, only weak correlations could be identified. A positive correlation was found between the parameters bone to implant contact and BMD (Spearman's rho .53; p = .05) whereas an inverse correlation was observed between BMD and implant stability (Spearman's rho -.61; p = .03). Both BoneProbe measurements in the cortical and trabecular area positively correlated with implant insertion torque (Spearman's rho 0.60; p = .02). A slightly stronger correlation was observed between the average of both BoneProbe measurements and implant insertion torque (Spearman's rho.66; p = .01). Conclusions: While establishing exact relationships among parameters of implant stability and the measurement techniques applied would require greater sample size, intraoperative compressive testing of bone might, despite the weak correlations seen here, be a useful tool for predicting primary implant stability.


Assuntos
Densidade Óssea , Implantação Dentária Endóssea/métodos , Implantes Dentários , Retenção em Prótese Dentária/métodos , Cuidados Intraoperatórios/métodos , Animais , Implantação Dentária Endóssea/instrumentação , Retenção em Prótese Dentária/instrumentação , Mandíbula/cirurgia , Modelos Animais , Projetos Piloto , Suínos , Porco Miniatura
10.
J Oral Pathol Med ; 46(1): 61-66, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27272434

RESUMO

BACKGROUND: Calcium phosphate (CaP) surface coatings may accelerate osseointegration and serve as a drug delivery system for mineral-binding biomolecules. In a pilot study, the impact of a commercially available, thin CaP coating on early osseous bone remodeling was compared with a modern, subtractive-treated rough surface (SLA-like) in an animal trial. METHODS: In 16 rabbits, 32 endosseous implants (CaP; n = 16, SLA-like; n = 16) were bilaterally inserted in the proximal tibia after randomization. After 2 and 4 weeks, bone-implant contact (BIC;%) in the cortical (cBIC) and the trabecular bone (sBIC) as well as volume of bone within the screw thread with the highest amount of new-formed bone (area;%) were analyzed. RESULTS: After 2 weeks, cBIC was significantly higher for CaP when compared with SLA-like (58 ± 7% versus 40.4 ± 18%; P = 0.021). sBIC for CaP was 14.7 ± 8% and for SLA-like 7.2 ± 7.8% (P = 0.081). For area, the mean volumes were 82.8 ± 10.8% for CaP and 73.6 ± 22% for SLA-like (P = 0.311). After 4 weeks, cBIC was 42.9 ± 13% for the CaP and 46.5 ± 29.1% for the SLA-like group (P = 0.775). An sBIC of 6.9 ± 9.3% was calculated for CaP and of 12.3 ± 4.8% for SLA-like (P = 0.202). The values for area were 62.3 ± 24.1% for CaP and 50.1 ± 25.9% for SLA-like (P = 0.379). CONCLUSIONS: The CaP coating has putative additional advantages in the early osseoconduction phases. It seems suitable for a feasible and clinical applicable bioactivation.


Assuntos
Fosfatos de Cálcio/farmacologia , Implantes Dentários , Planejamento de Prótese Dentária , Sistemas de Liberação de Medicamentos , Osseointegração/efeitos dos fármacos , Animais , Implantação Dentária Endóssea , Modelos Animais , Coelhos , Distribuição Aleatória , Titânio
11.
Clin Oral Implants Res ; 28(2): 201-206, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26771071

RESUMO

OBJECTIVES: To evaluate the effect of platelet-derived growth factor (rhPDGF-BB) on the promotion of osteogenesis around variable-thread tapered implants in an animal model. MATERIAL AND METHODS: Twenty-four variable-thread tapered implants were inserted in the tibia of 12 rabbits. Twelve sites received additional rhPDGF-BB released from a presoaked xenogenic bone block that was fixed supracrestally. Primary outcomes were bone-to-implant contact (BIC; in % ± SD) and percentage of medullary bone fill around the implants (PMF; in % ± SD) after 3 weeks (PDGF n = 6, no PDGF n = 6) and 6 weeks (PDGF n = 6, no PDGF n = 6). RESULTS: Considerable crestal and medullary bone remodeling could be found around all implants. After 3 weeks, both BIC and PMF values were higher in the no PDGF group (BIC: 63% ± 10 with PDGF vs. 85% ± 5 with no PDGF; PMF: 57% ± 10 with PDGF vs. 74% ± 4 with no PDGF). After 6 weeks, the BIC difference between the two groups was less distinct (BIC: 78% ± 17 with PDGF vs. 72% ± 25 with no PDGF), whereas the PDGF group showed higher PMF values (PMF: 77% ± 5 with PDGF vs. 56% ± 10 with no PDGF). CONCLUSIONS: The addition of rhPDGF-BB decreases early osseous crestal and medullar healing properties around dental implants. In a later phase, an increase in the cortical area as well as an increased medullar bone formation was seen. This response is likely to provide stronger secondary stability and stability in suboptimal situations involving poor-quality bone.


Assuntos
Remodelação Óssea/efeitos dos fármacos , Implantes Dentários , Fator de Crescimento Derivado de Plaquetas/farmacologia , Animais , Implantes Experimentais , Modelos Animais , Estudos Prospectivos , Coelhos , Tíbia/cirurgia
12.
Implant Dent ; 26(2): 250-255, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27922455

RESUMO

INTRODUCTION: The aim of this ex vivo study was to investigate the influence of different insertion torques on primary stability of a conical and a cylindrical implant system. MATERIALS AND METHODS: Thirty-two dental implants (Astra Tech OsseoSpeed 5.0 S × 11 mm cylindrical [n = 16] and 5.0 × 11 mm conical [n = 16]) were inserted with 20, 30, 40, and 45 N·cm into fresh porcine bone of mixed trabecular-cortical quality. Before insertion, bone quality was assessed via cone beam tomography. After insertion, resonance frequency analysis was reported using the implant stability quotient (ISQ). Implant insertion depths were evaluated, and the implants were pushed out of the bone by force (measured in N). All experiments were done with n = 4 per group. RESULTS: The highest ISQ (mean 78.25 ± 2.9) and pushout values (mean 675 N ± 5.8) were measured for the cylindrical implant after insertion using 30 N·cm. The conical implant showed the highest primary stability by means of ISQ (mean 76.25 ± 2.2) and pushout force (mean 502.5 N ± 9.6) after an insertion torque of 40 N·cm. If more insertion force was used, primary stability was reduced in all cases. CONCLUSION: The data indicate that different forms of an implant system need different insertion torques to obtain an optimal primary stability. These results have to be verified clinically.


Assuntos
Implantação Dentária/métodos , Implantes Dentários , Retenção em Prótese Dentária/métodos , Animais , Tomografia Computadorizada de Feixe Cônico , Implantação Dentária/efeitos adversos , Implantes Dentários/efeitos adversos , Retenção em Prótese Dentária/efeitos adversos , Falha de Restauração Dentária , Análise do Estresse Dentário , Suínos , Torque
13.
Clin Oral Implants Res ; 25(7): 774-80, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23590559

RESUMO

OBJECTIVES: The aim of this pilot study was to evaluate the vertical osteoconductive and osteointegrative dynamics around titanium-zirconium (TiZr) implants compared to titanium (Ti) implants. MATERIALS AND METHODS: In a split-leg design, 12 TiZr-SLActive and 12 Ti-SLActive implants were inserted 3 mm above bone level in the proximal tibia of 12 rabbits. Full periosteal flaps were repositioned to cover the site. Specimens were obtained after 10, 20 and 30 days (each n = 4 per group). Histomorphometric measurements included percentage of linear bone fill (PLF; %), new marginal vertical bone height (VBH; mm) and vertical bone-to-implant contact (vBIC; %). Statistical analysis was performed with the nonparametric F1_LD_F1 model to compare the two groups at the different time points. RESULTS: After 10 days, mean PLF was 7.7% (standard deviation (SD): 5.3) for TiZr and 17.6 (SD: 8.3) for Ti. Mean VBH was 0.35 mm (SD: 0.15) and 0.78 mm (SD: 0.4) for TiZr and Ti, respectively; mean vBIC was 24.4% (SD: 41) for TiZr and 53% (SD: 28.9) for Ti samples. The differences were significant for all parameters (PLF: P = 0.021; VBH: P = 0.009; vBIC: P = 0.011). After 20 days, mean PLF was 44.3% (SD: 26.3) for TIZr and 46.2% (SD: 21.3) for Ti implants. TiZr showed a mean VBH of 1.73 mm (SD: 1) and 1.8 mm (SD: 0.6) for Ti samples. Mean vBIC had values of 48.3% (SD: 23.7) and 68.7% (SD: 35.5) for TiZr and Ti, respectively (PLF: P = 0.78; VBH: P = 0.58; vBIC: P = 0.47). At the point of 30 days, mean PLF values were 23.7% (SD: 3.8) for TiZr and 28.9% (SD: 21.7) for Ti samples; mean for VBH in TiZr samples was 0.65 mm (SD: 0.39) and 1.7 mm (SD: 1.1) for Ti ones. Finally, mean vBIC was 28.3% (SD: 19.3) and 54.4% (SD: 26.5) for TiZr and Ti samples, respectively (PLF: P = 0.1; VBH: P = 0.088; vBIC: P = 0.089). CONCLUSIONS: A significant delay in vertical osteoconductivity at the earliest time point under examination was seen for TiZr implants when compared to their Ti counterparts. For the later points, TiZr as well as Ti implants demonstrated comparable values in this animal model. The long-term osteogenic surface properties of equally pretreated TiZr dental implants are therefore similar to those of Ti implants in vivo.


Assuntos
Condução Óssea/fisiologia , Implantação Dentária Endóssea/métodos , Implantes Dentários , Osteogênese/fisiologia , Animais , Planejamento de Prótese Dentária , Modelos Animais , Projetos Piloto , Coelhos , Propriedades de Superfície , Retalhos Cirúrgicos , Tíbia/cirurgia , Titânio , Zircônio
14.
Clin Implant Dent Relat Res ; 16(2): 194-201, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23675992

RESUMO

INTRODUCTION: Osteoconductive characteristics of different implant surface coatings are in the focus of current interest. The aim of the present study was to compare the vertical osteoconductivity at the implant shoulder of supracrestal inserted calcium-phosphate coated implants (SLA-CaP) with conventional sand-blasted/acid-etched (SLA) implants in a rabbit model. MATERIALS AND METHODS: SLA-CaP and SLA implants were inserted bilaterally in the mandible of four rabbits in a split-mouth design. The implants were placed 2 mm supracrestal. After 3 weeks, at the left and right implant shoulder, the percentage of linear bone fill (PLF) as well as bone-implant contact (BIC-D) were determined. RESULTS: After 3 weeks, newly formed woven bone could be found at the shoulder of the most of both surface-treated implants (75%). PLF was significantly higher in SLA-CaP implants (11.2% vs. 46.5%; n = 8, p = .008). BIC-D was significantly increased in the SLA-CaP implants (13.0% vs. 71.4%; n = 8, p < .001) as well. CONCLUSION: The results of this study show for the first time that calcium-phosphate coated surfaces on supracrestal inserted implants have vertical osteoconductive characteristics and increase the bone-implant contact at the implant shoulder significantly in a rabbit model. In clinical long-term settings, these implants may contribute to a better vertical bone height.


Assuntos
Fosfatos de Cálcio , Materiais Revestidos Biocompatíveis , Implantes Dentários , Titânio , Condicionamento Ácido do Dente , Animais , Projetos Piloto , Coelhos , Propriedades de Superfície
16.
Int J Oral Maxillofac Implants ; 28(5): 1254-60, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24066315

RESUMO

PURPOSE: A novel diagnostic device (BoneProbe) for evaluating alveolar bone quality during dental implant surgery has recently been developed. The underlying measurement principle is based on a compressive test of bone, which may subsequently affect bone healing and osseointegration of dental implants. MATERIALS AND METHODS: Six implant sites each were created in the rear left tibia of four sheep and used for bone quality testing with the BoneProbe, while empty osteotomies and implants placed without testing served as controls. Maximum insertion torque and primary implant stability (Osstell) were determined additionally. After 5 and 20 weeks, the animals were sacrificed followed by histomorphometric and microradiographic analysis quantifying bone implant contact (BIC) and bone mineral density (BMD) as parameters. Statistical analysis was conducted applying one-sample t tests, two-sample t tests and Pearson correlation coefficients (α = .05). RESULTS: Implants placed following application of the BoneProbe differed from the control treatments only in one case, where BIC was greater (P = .02) at the control implant after 20 weeks of healing. With the exception of the combinations of Osstell/BoneProbe measurement in trabecular bone (0.29) and Osstell/insertion torque (0.34), good correlations of all clinically conducted measurements were found. CONCLUSION: Based on the results obtained, it appears that intraoperative testing of bone quality applying the BoneProbe does not jeopardize bone healing and osseointegration of dental implants.


Assuntos
Densidade Óssea , Implantação Dentária Endóssea , Implantes Dentários , Retenção em Prótese Dentária , Osseointegração , Tíbia/fisiologia , Cicatrização , Animais , Feminino , Osteotomia , Cuidados Pré-Operatórios/instrumentação , Ovinos , Torque
17.
Artigo em Inglês | MEDLINE | ID: mdl-22676931

RESUMO

OBJECTIVE: The purpose of this clinical prospective, randomized, double-blind study was to compare the anesthetic efficacy of 4% articaine with epinephrine (1:100,000) and without epinephrine in inferior alveolar nerve block anesthesia for extractions of mandibular teeth. STUDY DESIGN: Eighty-eight patients received intraoral inferior alveolar nerve blocks using 4% articaine with 1:100,000 epinephrine (n = 41; group 1) or without epinephrine (n = 47; group 2) for extractions of mandibular teeth. The primary objectives were differences in onset as well as in length of soft tissue anesthesia. The amount of anesthetic solution, need of a second injection, pain while injecting, pain during treatment, postoperative pain, and possible complications were surveyed. RESULTS: In both groups, anesthesia was sufficient for dental extractions. In group 1, a significantly faster onset of the anesthetic effect (7.2 min vs. 9.2 min; P = .001) and a significantly longer duration of soft tissue anesthesia (3.8 h vs. 2.5 h; P < .0001) were seen. There was no significant difference in the amount of anesthetic solution needed, in the need for a second injection, in the injection pain, in pain during treatment, or in postoperative analgesia. In both groups, no complications were seen. CONCLUSIONS: To minimize the epinephrine-induced side effects, 4% articaine without epinephrine is a suitable anesthetic agent for dental extractions in the mandible after inferior alveolar nerve block anesthesia. There could be less postoperative discomfort due to the shorter duration of anesthesia without increased postoperative pain.


Assuntos
Anestesia Dentária/métodos , Anestésicos Locais , Carticaína , Epinefrina , Bloqueio Nervoso/métodos , Extração Dentária , Vasoconstritores , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Método Duplo-Cego , Feminino , Humanos , Masculino , Nervo Mandibular , Pessoa de Meia-Idade , Duração da Cirurgia , Dor Pós-Operatória , Estudos Prospectivos , Adulto Jovem
18.
Clin Implant Dent Relat Res ; 14 Suppl 1: e169-74, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22145692

RESUMO

BACKGROUND: Ceramic biomaterial blocks like hydroxyl apatite are too brittle for simple simultaneous vertical augmentation and dental implant placement. Biological scaffolds of xenogenic or allogenic origin are known to be advantageous. PURPOSE: The aim of this study was the proof of principle for combined vertical bone augmentation and dental implantation with marginal cuffs made of biological scaffolds with interconnecting porous system and titanium dental implants. MATERIALS AND METHODS: Cylindrical porcine biomaterial rings (processed, mineralized bone matrix) were placed in combination with titanium dental implants in the tibia model using six chinchilla bastard rabbits (n = 12 samples). Histological examination included undecalcified histological examination with toluidine blue staining and fluorescence microscopy. Animals were sacrificed after 30 days. RESULTS: The results showed bony healing in the scaffolds with immature bone tissue ingrowth following the trabecular structure, showing lamellar cancellous bone healing. Fluorescence microscope showed analogous results. CONCLUSION: The biological scaffold proved a biocompatibility in a xenogenic setting. The vertical bone augmentation with simultaneous implantation was successful and proved the feasibility of the concept.


Assuntos
Aumento do Rebordo Alveolar/métodos , Materiais Biocompatíveis , Carga Imediata em Implante Dentário/métodos , Alicerces Teciduais , Animais , Matriz Óssea/transplante , Calcificação Fisiológica/fisiologia , Corantes , Materiais Dentários/química , Feminino , Microscopia de Fluorescência , Osseointegração/fisiologia , Osteogênese/fisiologia , Porosidade , Coelhos , Suínos , Tíbia/patologia , Tíbia/cirurgia , Titânio/química , Cloreto de Tolônio , Transplante Heterólogo
19.
Clin Oral Implants Res ; 23(2): 257-260, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21635558

RESUMO

AIM: The purpose of the EAO summer camp was to create visions and ideas for future developments in the field of implant dentistry. An additional goal was the installation of a young, strong and enduring network for scientific exchange among participants. SUMMER CAMP ACTIVITY: Forty participants younger than 40 years of age, from 16 different European countries, discussed potential future developments of implant dentistry in a professionally moderated workshop. Participants worked in a competitive manner over 3 days in small teams on four topics: future teaching and education, surgery in 2030, prosthetics in 2030 and futuristic tissue development related to the field of implantology. Various innovative conference and moderation techniques were applied to achieve a maximum output from the creative potential present. RESULTS: Plenum consensus was obtained for several key factors potentially influencing future development in implant dentistry. In particular, teaching and education will be improved by the establishment of curriculum standards and novel teaching technologies. Surgery in 2030 will benefit from an improved cost-effectiveness of new technologies and biomaterials. A more comprehensive knowledge on host susceptibility will have an impact on treatment planning and the predictability of implant therapy. A virtual patient concept and tissue engineering will influence Prosthodontics in 2030. Futuristic tissue development will set a "platinum standard" for tissue regeneration. SUMMARY: Visions on all four topics were generated and discussed intensively during the conference. "Future teaching and education" was voted unanimously as the winning team based on the presented ideas and the special interest this topic generated.


Assuntos
Prostodontia/educação , Adulto , Congressos como Assunto , Europa (Continente) , Feminino , Humanos , Masculino
20.
Clin Oral Investig ; 16(4): 1039-48, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21822603

RESUMO

This study aims to investigate the early outcome of a dental implant with bioactive calcium-phosphate (CaP) coating in the first year of usage in different clinical indications in partially edentulous patients, after early and delayed prosthetic loading. Therefore, in a prospective follow-up study, the cumulative survival and success rate of a conical, self-drilling and self-tapping implant system after 6 months and 1 year post-insertion was evaluated. A total of 311 CaP-coated implants were placed in 124 patients. Seventy-two implants in clinical high-quality bone situation were loaded after 2 weeks post-insertion with the definite restoration; the rest after 6 months. The indication for implant placement was treatment of partial dentate mandible and maxilla. One hundred sixty-three implants were placed in the posterior mandible, 117 in the posterior maxilla. In the frontal maxilla, 25 implants and in the frontal mandible, eight implants were used. In 126 cases (36%), bone augmentation procedures (guided bone regeneration and sinus lift) were performed concomitant with implant placement. The difference between primary and secondary stability (implant stability quotient (ISQ), Periotest, insertion torque), peri-implant clinical parameter as well as survival and success criteria were evaluated. In total, ISQ mean values after 6 months were higher than after implant placement. Periotest values increased in the period of the first 6 months and remained constant afterwards. After 6 months of insertion, the mean bone loss was 0.051 mm. After 12 months, a bone gain with a mean of +0.016 mm was observed; implants in the posterior maxilla showed significant less bone resorption than implants in the posterior mandible (p < 0.0001). In the most of the implants (74%), clinical normal gingival tissue could be observed. In 24%, a mild inflammation was analysed. In 35 implants, a provocation of peri-implant bleeding was possible. In the early loading group, no implant failure was seen. Altogether, one implant in D4 bone has been lost. The cumulative survival rate summed up to 99.7%. In general, implant success assessment analysis according to Albrektsson and Buser displayed success in 99.7% of the implants. With respect to the patient selection including 124 implants with minor and major augmentations as well as early loading prosthetic function, the 1-year clinical use of the studied implant system with CaP coating showed good results, comparable to that of conventional implants without a specific coating. After 1 year, neither special disadvantages nor benefits of CaP-coated implants could be evaluated. Long-term results are further needed.


Assuntos
Fosfatos de Cálcio/química , Materiais Revestidos Biocompatíveis/química , Implantes Dentários , Planejamento de Prótese Dentária , Arcada Parcialmente Edêntula/cirurgia , Adolescente , Adulto , Perda do Osso Alveolar/etiologia , Aumento do Rebordo Alveolar/métodos , Densidade Óssea/fisiologia , Remodelação Óssea/fisiologia , Índice de Placa Dentária , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Feminino , Seguimentos , Regeneração Tecidual Guiada Periodontal/métodos , Humanos , Carga Imediata em Implante Dentário/métodos , Arcada Parcialmente Edêntula/reabilitação , Masculino , Pessoa de Meia-Idade , Osseointegração/fisiologia , Índice Periodontal , Estudos Prospectivos , Levantamento do Assoalho do Seio Maxilar/métodos , Propriedades de Superfície , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
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