Primary and Secondary Stability of Implants with Hydrophilic Surfaces in the Posterior Maxilla: A Split-Mouth Randomized Controlled Clinical Trial.

PURPOSE: The aim of this split-mouth randomized clinical trial was to evaluate the primary and secondary stability of implants with hydrophilic surfaces in comparison to implants with conventional surfaces in the posterior region of the maxilla. MATERIALS AND METHODS: Twenty patients with a bilateral edentulous ridge in the posterior area of the maxilla randomly received implants with two types of surfaces: (1) implants with the surface modified by double acid-etching and sandblasting (DAS, n = 20); and (2) implants with the surface modified by double acid-etching and sandblasting, stored in 0.9% saline solution to confer highly hydrophilic properties (DAS-H, n = 20) on the surface. The implants presented the same macrostructure with a hybrid design. The resonance frequency analysis was performed in order to obtain the implant stability quotient (ISQ) using Osstell. The ISQ analyses were performed just after placement of the implant (primary stability) and at 28, 40, and 90 days after the surgical procedure (secondary stability). RESULTS: There were no differences between the DAS and DAS-H surfaces in the primary stability or during the conversion of the primary to the secondary stability; however, there was a reduction in the stability of the implants at 28 days, which increased significantly at 40 and 90 days in both surfaces. CONCLUSION: It can be concluded that the surface wettability of implants with a hybrid macrostructure did not increase the primary and secondary implant stability in the posterior region of the maxilla.

Bone Formed After Maxillary Sinus Floor Augmentation by Bone Autografting With Hydroxyapatite and Low-Level Laser Therapy: A Randomized Controlled Trial With Histomorphometrical and Immunohistochemical Analyses.

PURPOSE: The aim of this study was to evaluate the bone formed after maxillary sinus floor augmentation (MSFA) by bone autografting combined with hydroxyapatite (HA) that had been either treated with low-level laser therapy (LLLT) or not. MATERIALS AND METHODS: Twelve biopsies were obtained from patients 6 months after MSFA using a combination of 50% of autogenous bone (AB) and 50% of HA (AB/HA group, n = 6) followed by LLLT (AB/HA-LLLT group, n = 6). The laser used in this study was gallium-aluminium-arsenide laser with a wavelength of 830 nm (40 mW; 5.32 J/point; 0.57 W/cm). Samples obtained were subjected to histological, histometric, and immunohistochemical analysis for detection of tartrate-resistant acid phosphatase and runt-related transcription factor 2. The data were submitted to statistical analysis (Shapiro-Wilk and Student t tests; α = 5%). RESULTS: Statistical analysis revealed no significant difference in vital bone presence and immunohistochemical analysis between the groups. There was no reduction in bone marrow or fibrous tissue in the AB/HA group and AB/HA-LLLT group. There was a decrease in the amount of remaining biomaterial between the groups (P = 0.0081). CONCLUSION: LLLT did not increase the formation of new bone; instead, it accelerated the bone remodeling process.

Effect of the long-term administration of Cyclosporine A on bone healing around osseointegrated titanium implants: A histomorphometric study in the rabbit tibia.

The aim of this study was to investigate the effect of cyclosporine A (CsA) therapy on bone healing around osseointegrated implants in the rabbit by means of descriptive histologic and histomorphometric analyses. Eighteen rabbits received one implant each in the right tibia proximal metaphysis. After the bone-healing period of 3 months, 6 randomly selected animals were sacrificed (Group CTL-12) before the immunosuppression therapy initiation to obtain a standard of implant integration. Another six randomly selected animals were submitted to a daily subcutaneous (sc) injection of 10 mg/kg CsA (Group CsA) whereas the six remaining animals received daily sc injections of saline solution (Group CTL-24). Groups CTL-24 and CsA were sacrificed after another 12 weeks. Bone-to-implant contact (BIC), and bone area fraction occupancy (BAFO) within the implant threads were measured. Bone density (BD) and descriptive histological analyses were also accomplished. Rabbits under CsA therapy presented statistically lower percentage of BIC (33.28 ± 6.19) compared to the animals of CLT-24 (55.6 ± 17.73). No differences were found between CsA and CTL-12 (38.7 ± 7.87). Significant decreased percentage of BAFO between the implant threads in the CsA (48.43 ± 9.48) group compared to the CTL-24 (72.26 ± 11.72) was observed. No differences were found between CsA and CTL-12 (61.99 ± 13.94) groups. BD analysis showed significant lower BD in the CsA (48.56 ± 9.32) group compared to the CTL-12 (68.74 ± 10.89) and CTL-24 (77.96 ± 4.96) groups. Collectively, our findings demonstrated that CsA therapy negatively affect the bone healing around osseointegrated implants due to the significant lower values for BIC, BAFO, and BD.

Tomographic Evaluation of Prevalence, Position, and Diameter of the Intraosseous Branch of the Posterior Superior Alveolar Artery in Fully Edentulous Individuals.

The objective of this study was to evaluate the presence, position, and diameter of the intraosseous branch (IObr) of the posterior superior alveolar artery in fully edentulous patients. Two-hundred five computed tomography scans of fully edentulous patients were analyzed. The presence of the IObr was investigated in the coronal plane at the lateral wall of the maxillary sinus. In patients in whom the IObr was detected, the artery diameter was measured, and the distance from the artery to the bone crest of the alveolar ridge, the maxillary sinus floor, and the distance of the maxillary sinus floor to the bone crest of the alveolar ridge were measured as well. A descriptive statistical analysis of these parameters was conducted. The IObr was identified in the maxillary sinus in 105 tomography images (51.2%), and its diameter varied between 0.8 and 3.3 mm (1.29 ±â€Š0.49 mm). The IObr presented with an artery diameter less than 1 mm in 29% of the patients, between 1 and 2 mm diameter in 61% of the patients and with a diameter larger than 2 mm in 10% of patients. Regarding the IObr topography, the distance from the artery to the floor of the maxillary sinus was 9.62 ±â€Š4.59 mm, and the distance from the artery to the top of crestal bone was 15.15 ±â€Š4.47 mm. At least 10% of edentulous patients are at risk of bleeding complications during interventions in the maxillary sinus.

Comparison of the Primary and Secondary Stability of Implants with Anodized Surfaces and Implants Treated by Acids: A Split-Mouth Randomized Controlled Clinical Trial.

PURPOSE: The objective of this randomized controlled clinical split-mouth trial was to compare anodized implant surfaces and implant surfaces modified by acid etching in terms of primary and secondary stability. MATERIALS AND METHODS: Forty-six implants were placed bilaterally in the posterior mandibles of 23 patients. Each patient received one implant with a surface treated by acid (AC) and the other with an anodized implant surface (ANO). The selection of the side where the implant was placed was chosen randomly by lot. The implants were evaluated with respect to insertion torque within the surgical bed and primary and secondary stability by testing the implant stability quotient (ISQ) at five different times (immediate postoperative period and 21, 30, 60, and 180 days after surgery). The paired t test was used to compare the two groups, and ANOVA Repeated Measures complemented by the Tukey posttest were used for longitudinal analysis of the implants in each group. All tests were applied with a confidence level of 95% (P < .05). RESULTS: No statistically significant difference was detected between the AC and ANO groups regarding insertion torque. ISQ analysis revealed that the AC group showed statistically higher values than the ANO group at the 21-day period (P < .05); however, no other statistically significant differences were detected at the other times. CONCLUSION: The different surfaces were similar in terms of primary and secondary stability of implants placed in the posterior mandible.

Torque Analysis of a Triple Acid-Etched Titanium Implant Surface.

The present study aimed to evaluate the removal torque of titanium implants treated with triple acid etching. Twenty-one rats were used in this study. For all animals, the tibia was prepared with a 2 mm drill, and a titanium implant (2 × 4 mm) was inserted after treatment using the subtraction method of triple acid etching. The flaps were sutured. Seven animals were killed 14, 28, and 63 days after implant installation, and the load necessary for removing the implant from the bone was evaluated by using a torque meter. The torque values were as follows: 3.3 ± 1.7 Ncm (14 days), 2.2 ± 1.3 Ncm (28 days), and 6.7 ± 1.4 Ncm (63 days). The torque value at the final healing period (63 days) was statistically significantly different from that at other time points tested (ANOVA, p = 0.0002). This preliminary study revealed that treatment with triple acid etching can create a promising and efficient surface for the process of osseointegration.

Patient discomfort following single-tooth implant placement: a randomized controlled trial of immediate vs. conventional tooth restoration.

AIMS: Evaluate postoperative discomfort (pain, bleeding and swelling) in single-tooth implant patients submitted to immediate or conventional tooth restoration together with assessment of treatment time. METHODS: Twenty-four patients who received single-tooth maxillary dental implants were randomly assigned to an IR (Immediate Restoration) or CR (Conventional Restoration) group. In IR, an implant was inserted and a provisional tooth crown was delivered within the same session, while in CR it was delivered three months after implantation. Pain (first three days), bleeding (first day) and swelling (first seven days) were assessed using a questionnaire with Visual Analogue Scales (VAS). RESULTS: Treatment time was longer for IR than for CR (57±14 and 33±8 min, respectively; p<0.0001). Mean VAS scores for pain, bleeding, and swelling were low for both groups at the first postoperative day. VAS scores for pain and swelling decreased continuously over the time period in both groups. CONCLUSIONS: The longer treatment time in IR didn't increase patients' perception of pain, bleeding and swelling, compared to CR. The impact of immediate tooth restoration on patients' esthetic outcome should be further considered.

Avaliação clínica em curto prazo do sistema de Cone Morse e plataforma reduzida em prótese sobre implantes do tipo protocolo: estudo piloto randomizado controlado / Short-term clinical evaluation of morse taper and platform switching in implant-supported protocol-type prosthesis: pilot randomized controlled study

Introdução: Implantes dentários com conexões do tipo Cone Morse combinados a plataforma reduzida podem minimizar a reabsorção da crista óssea perimplantar. Entretanto, ainda não está claro se seu uso resultaria também em uma melhor manutenção da altura dos tecidos moles, o que poderia interferir no resultado estético final. Objetivo: Este estudo teve o objetivo de avaliar os tecidos moles ao redor de implantes dentários com Cone Morse, comparativamente àqueles com hexágono interno, em pacientes com edentulismo total, submetidos a carregamento imediato com prótese total fixa inferior. Material e método: Dez pacientes tiveram quatro implantes instalados na mandíbula, dois com Cone Morse e dois com hexágono interno, sendo a prótese instalada 72 horas após esse procedimento. Três meses depois, o índice de placa, o índice de sangramento à sondagem, a profundidade de sondagem, a posição do tecido marginal e o nível de inserção relativo foram avaliados pelos testes t e Wilcoxon (α = 5%). Resultado: Nos implantes com Cone Morse, a profundidade de sondagem foi significantemente menor do que naqueles com hexágono interno (p = 0,02). Nos implantes com Cone Morse, o tecido marginal estava em média 0,6 mm coronal à junção prótese-conector protético, enquanto que, nos implantes com hexágono interno, o tecido marginal esteve em média 0,4 mm apical à junção prótese-componente protético (p = 0,001). Adicionalmente, a inserção clínica nos implantes com Cone Morse estava em um nível mais coronal do que naqueles com hexágono interno (p = 0,02). Conclusão: Nas condições estudadas, os implantes do sistema Cone Morse se mostraram mais eficientes em manter a altura dos tecidos moles perimplantares do que os implantes do sistema hexágono interno.

Introduction: Dental implants with Morse taper connection combined with platform switching may minimize peri-implant crestal bone resorption. However, it remains unclear whether its use would better maintain soft tissue height, which could interfere with the esthetic outcome. Objective: The aim of this study was to evaluate the soft tissue around dental implants with Morse taper, compared to implants with internal hexagon connection, in patients with total edentulism who were submitted to immediate loading with lower fixed complete dentures. Material and method: Ten patients had four implants installed in the mandible, two with Morse taper and two with internal hexagon; and a provisional prosthesis was installed 72 hours afterward. Three months later, plaque index, bleeding on probing index, probing depth, position of soft tissue margin, and relative attachment level. Result: In implants with Morse taper, probing depth was significantly lower than in those with internal hexagon (p = 0.02). In Morse taper implants, the soft tissue margin was positioned 0.6 mm coronal to the prosthesis-abutment junction; in internal hexagon implants, marginal tissue was 0.4 mm apical to the prosthesis-abutment junction (p = 0.001). Additionally, in the Morse taper implants, the attachment level was at a more coronal level than in the internal hexagon implants (p = 0.02). Conclusion: Under the conditions studied, implants with the Morse taper connection were more effective in maintaining the height of peri-implant soft tissue than implants with internal hexagon.

Problemas na junção implante/prótese: uma alternativa para resolução do caso / Problems at the implant/prosthesis junction: an alternative for solving the case

A Implantodontia vem se destacando entre as diversas áreas da Odontologia moderna. As possibilidades de tratamento envolvendo os implantes dentários têm facilitado e ampliado a gama de opções ao cirurgião dentista. No entanto, a proposta de tratamento envolvendo reabilitação sobre implantes traz consigo problemas a serem solucionados, já que tal tratamento também é passível de intercorrências. A curva de aprendizagem com o emprego da Implantodontia deve ser respeitada, já que tanto na fase cirúrgica quanto na fase protética, existem critérios a serem respeitados para um bom prognóstico do tratamento. Além disso, quando surgem as intercorrências é imprescindível o preparo e conhecimento do profissional em questão. O presente caso clínico relata uma reabilitação unitária sobre implante, a qual necessitou ser realizada fora dos padrões normais da Implantodontia, já que foi constatada deformação na plataforma hexagonal do mesmo. É possível que tal ocorrência tenha sido causada na fase cirúrgica, durante a instalação do implante, devido a um provável torque excessivo, resultando na impossibilidade da adaptação dos componentes protéticos. A resolução do caso ocorreu com a instalação de um núcleo metálico fundido sobre o implante e confecção de prótese metalocerâmica cimentada. Com o presente relato, pode-se notar a importância do conhecimento de conceitos básicos por parte do cirurgião dentista, assim como sua flexibilidade frente às intercorrências do tratamento

The Implantology has become highlighted among the various areas of modern dentistry. The treatment possibilities involving dental implants have facilitated and expanded the range of options to the dentist. However, the treatment involving rehabilitation with implants can bring problems to be solved, as this treatment is also susceptible to complications. Learning curve with the use of implants should be respected, both in the surgical and prosthetic phases, because there are criteria to be met for a good treatment prognosis. Also, when complications occur, it is essential preparation and knowledge of the professional. This case report describes unit rehabilitation with implant, which needed to be performed outside of the normal standards of implant dentistry, as was observed deformation on the hexagonal platform. It is possible that it has been caused during implant installation surgery phase, due to an excessive torque, resulting in the inability to adapt the prosthetic components. The case resolution was with the installation of a cast metal core on the implant and making a metaloceramic cemented prosthesis. With this case report may be noted the importance of knowledge of basic concepts by the dentist, as well as its flexibility in the face of complications of treatment

Measurements of simulated periodontal bone defects in inverted digital image and film-based radiograph: an in vitro study.

PURPOSE: This study was performed to compare the inverted digital images and film-based images of dry pig mandibles to measure the periodontal bone defect depth. MATERIALS AND METHODS: Forty 2-wall bone defects were made in the proximal region of the premolar in the dry pig mandibles. The digital and conventional radiographs were taken using a Schick sensor and Kodak F-speed intraoral film. Image manipulation (inversion) was performed using Adobe Photoshop 7.0 software. Four trained examiners made all of the radiographic measurements in millimeters a total of three times from the cementoenamel junction to the most apical extension of the bone loss with both types of images: inverted digital and film. The measurements were also made in dry mandibles using a periodontal probe and digital caliper. The Student's t-test was used to compare the depth measurements obtained from the two types of images and direct visual measurement in the dry mandibles. A significance level of 0.05 for a 95% confidence interval was used for each comparison. RESULTS: There was a significant difference between depth measurements in the inverted digital images and direct visual measurements (p>|t|=0.0039), with means of 6.29 mm (IC(95%):6.04-6.54) and 6.79 mm (IC(95%):6.45-7.11), respectively. There was a non-significant difference between the film-based radiographs and direct visual measurements (p>|t|=0.4950), with means of 6.64mm(IC(95%):6.40-6.89) and 6.79mm(IC(95%):6.45-7.11), respectively. CONCLUSION: The periodontal bone defect measurements in the inverted digital images were inferior to film-based radiographs, underestimating the amount of bone loss.

Gengivite plasmocitária induzida por uso de pimenta / Plasma cell gingivitis induced by papper consupsion: a case report

O objetivo desse estudo foi de apresentar um relato de caso em que o paciente apresentava gengivite plasmocitária induzida por consumo de pimenta. Paciente AMS, sexo masculino, 23 anos, apresentou-se na Clínica de Periodontia, queixando-se de dor intensa, sangramento gengival e mobilidade dental. Foi realizada anamnese não observando-se nada relevante. Na avaliação bucal, observou-se na região anterior gengival edemaciada, sangramento ao toque e grande supuração, além de mobilidade dental. Tratando-se de um quadro agressivo em relação à idade do paciente, foram realizados os seguintes exames complementares: hemograma completo, taxa de glicemia e coagulograma, bem como biópsia, na região anterior inferior, devido a suspeita diagnóstica de linfoma. Ao final da antibioticoterapia, houve melhora significativa do quadro clínico, alívio da dor, gengiva menos edemaciada e redução da supuração e mobilidade. Os exames laboratoriais não apresentaram nenhuma alteração; 15 dias após, o paciente retornou com piora do quadro clínico. O diagnóstico histopatológico foi de gengivite plasmocitária e, então, foi realizada nova anamnese dando maior importância aos hábitos alimentares, sendo que o paciente relatou consumo de pimenta em suas refeições, fato relacionado ao quadro clínico apresentado. Após a eliminação da pimenta da dieta, o paciente apresentou remissão dos dados clínicos.

Homeopathic Symphytum officinale increases removal torque and radiographic bone density around titanium implants in rats.

INTRODUCTION: This study evaluated the effect of Symphytum officinale in homeopathic potency (6cH), on the removal torque and radiographic bone density around titanium implants, inserted in rats tibiae. METHODS: Implants were placed in male rat tibiae, and the animals randomized to two groups (Control and S. officinale 6cH treated), which were evaluated at 7, 14, 28 and 56 days post-implantation. Radiographic bone density was measured at 6 points around the implant, using digital radiographic images, when implants were inserted and at sacrifice. Removal torque of the implants was also evaluated. RESULTS: Both removal torque and radiographic bone density evaluation showed that S. officinale 6cH treatment enhanced bone formation around the micro-implants, mainly at 14 days. At 56 days, the radiographic bone density was higher in the treated group. CONCLUSIONS: We conclude that S. officinale 6cH enhances, principally at the early stages of osseointegration, bone formation around titanium implants in rats' tibiae, based on radiographic and mechanical analysis.

Avaliação dos implantes Nobel Direct por subtração radiográfica digital sob novo protocolo protético / Evaluation of Nobel Direct implants by digital subtraction radiography under new prosthetic protocol

O implante peça única Nobel Direct (Pund) foi preconizado para prevenir perda óssea alveolar marginal pela sua macrogeometria e por proporcionar ausência de microgap entre fixação e o componente protético. O objetivo deste estudo foi verificar através de subtração radiográfica digital de Punds submetidos à carga imediata sob novo protocolo protético. Inicialmente foram selecionados 20 implantes em 20 pacientes. O estudo seguiu avaliando oito implantes mensalmente durante os primeiros seis meses de osseointegração através de subtração digital (CDR-Shick - X-Poesit) realizada com radiografias padronizadas por placa oclusal personalizada. A média de quantidade de pixels relacionados à perda óssea (QPPO) foi 480,3 e a média de quantidade de pixels relacionados ao ganho ósseo (QPGO) foi 54,5 (p=0,011). A média de perda óssea vertical aferida pelo programa Image tool-3.0 foi de 1,04 mm durante os primeiros seis meses pós-instalação dos Pund. Concluiu-se que este sistema não previne perda óssea alveolar marginal, em especial nos primeiros seis meses pós-instalação. Porém, a partir da instalação das coroas definitivas, a remodelação óssea tende a diminuir, estabilizando a distância biológica estabelecida, com resultados semelhantes aos implantes convencionais de duas peças. Durante 40 meses de controle clínico não houve perdas e todos os 20 implantes obtiveram sucesso.

The Nobel Direct One-Piece Implant (Pund) has being recommended to prevent marginal bone resorption. The argument is that this system provides no implant-abutment microgap. The aim of this study was to verify this issue using Digital Subtraction Radiography at immediate loaded Punds according to a new prosthetic protocol. First, 20 implants were selected in 20 patients. Then, the study followed evaluating eight implants monthly during the first six months of osseointegration through digital subtraction (CDR-Shick - X-Poesit) performed with standardized radiographs by an individual oclusal index. The average pixels-related bone loss (QPPO) was 480.3 and the pixels gain related to increased bone (QPGO) was 54.5 (p=0.011). The mean vertical bone loss verified by Image tool - 3.0 Program was 1.04 mm during the first six months after Pund installation. It was concluded that this system does not prevent alveolar bone loss especially in the first six postoperative months. However, the bone turnover tends to decrease after delivery of definitive crowns, stabilizing the biological distance acquired, with results similar to conventional, two-piece implants. During 40 months no implant was lost and the 20 fixtures were considered successful.

Influence of homeopathic treatment with comfrey on bone density around titanium implants: a digital subtraction radiography study in rats.

OBJECTIVE: The objective of this study was to evaluate the influence of homeopathic treatment with comfrey (Shymphytum officinalis 6CH) on radiographic bone density and area around titanium implants. MATERIAL AND METHODS: Forty-eight rats were divided into two groups of 24 animals each: a control group (C) and a test group (SO). Each animal received one titanium micro-implant placed in the tibia. The animals in Group SO were subjected to 10 drops of comfrey 6CH per day mixed into their drinking water until the day of sacrifice. Eight animals of each group were sacrificed at 7, 14 and 28 days post-surgery, respectively. Standardized digital radiographs were obtained on the day of implant installation (baseline images) and on the day of sacrifice (final images). Digital subtraction of the two corresponding images was performed to evaluate changes in bone density and the area related to change around the implant between baseline and final images. RESULTS: Subtraction images demonstrated that a significant difference existed in mean shade of gray at 14 days post-surgery between Group SO (mean 175.3+/-14.4) and Group C (mean 146.2+/-5.2). Regarding the area in pixels corresponding to the bone gain in Group SO, the differences observed between the sacrifice periods and groups were only significant at 7 days sacrifice between Group SO (mean 171.2+/-21.9) and Group C (mean 64.5+/-60.4). CONCLUSION: Within the limits of this study, comfrey administration promotes an increase in radiographic bone density around titanium implants in the initial period of bone healing.

Influence of estrogen deficiency and its treatment with alendronate and estrogen on bone density around osseointegrated implants: radiographic study in female rats.

OBJECTIVE: This study evaluated the influence of estrogen deficiency and its treatment on bone density around integrated implants. STUDY DESIGN: Implants were placed in female rat tibiae. The animals were assigned to 5 groups: control, sham, ovariectomy, estrogen, and alendronate. The control group was humanely killed to confirm integration of the implant. The others were submitted to ovariectomy or sham surgery. Bone density was measured by digital radiographs at 6 points on sides of the implant. RESULTS: The analysis of radiographic bone density revealed estrogen privation had a negative impact only in the cancellous bone. The estrogen group differed significantly (P < .05) from the ovariectomy and alendronate groups. The alendronate group presented the highest density for all evaluated regions. CONCLUSION: Ovariectomy caused a decrease in the radiographic bone density in the cancellous region. Estrogen replacement therapy and alendronate were effective treatments in preventing bone mass loss around integrated implants.

A survey of radiographic measurement estimation in assessment of dental implant length.

The aim of this study is to survey radiographic measurement estimation in the assessment of dental implant length according to dentists' confidence. A 19-point questionnaire with closed-ended questions was used by two graduate students to interview 69 dentists during a dental implant meeting. Included were 12 questions related to over- and underestimation in three radiographic modalities: panoramic (P), conventional tomography (T), and computerized tomography (CT). The database was analyzed by Epi-Info 6.04 software and the values from two radiographic modalities, P and T, were compared using a chi2 test. The results showed that 38.24% of the dentists' confidence was in the overestimation of measurements in P, 30.56% in T, and 0% in CT. On the other hand, considering the underestimated measurements, the percentages were 47.06% in P, 33.33% in T, and 1.92% in CT. The frequency of under- and overestimation were statistically significant (chi2 = 6.32; P = .0425) between P and T. CT was the radiographic modality with higher measurement precision according to dentists' confidence. In conclusion, the interviewed dentists felt that CT was the best radiographic modality when considering the measurement estimation precision in preoperative dental implant assessment.

Effect of 17beta-estradiol and alendronate on the removal torque of osseointegrated titanium implants in ovariectomized rats.

BACKGROUND: This study investigated the influence of estrogen deficiency and its treatment with estrogen and alendronate on the removal torque of osseointegrated titanium implants. METHODS: Fifty-eight female Wistar rats received a titanium implant in the tibia metaphysis. After 60 days, which was needed for implant osseointegration, the animals were randomly divided into five groups: control (CTLE; N = 10), sham surgery (SHAM; N = 12), ovariectomy (OVX; N = 12), ovariectomy followed by hormone replacement (EST; N = 12), and ovariectomy followed by treatment with alendronate (ALE; N = 12). The CTLE group was sacrificed to confirm osseointegration, whereas the remaining groups were submitted to sham surgery or ovariectomy according to their designations. After 90 days, these animals were also sacrificed. Densitometry of femur and lumbar vertebrae was performed by dual-energy x-ray absorptiometry (DXA) to confirm systemic impairment of the animals. All implants were subjected to removal torque. RESULTS: Densitometric analysis of the femur and lumbar vertebrae confirmed a systemic impairment of the animals, disclosing lower values of bone mineral density for OVX. Analysis of the removal torque of the implants showed statistically lower values (P <0.05) for the OVX group in relation to the other groups. However, the group treated with alendronate (ALE group) presented significantly higher torque values compared to the others. CONCLUSION: According to this study, estrogen deficiency was observed to have a negative influence on the removal torque of osseointegrated implants, whereas treatment with alendronate increased the torque needed to remove the implants.

Creeping attachment após enxerto gengival livre: relato de caso com 14 anos de proservação / Creeping attachment after free gingival grafting: 14 years follow-up case report

O enxerto gengival livre é um procedimento mucogengival indicado preferencialmente para criar mucosa queratinizada, podendo ocorrer também o recobrimento radicular das raízes desnudas. O creeping attachment é um fenômeno descrito como a migração pós-operatória do tecido gengival marginal em direção coronal; assim, é considerado um evento bastante positivo no sentido de se obter um ganho adicional de tecido queratinizado na área envolvida. Estudos longitudinais têm mostrado uma maior ocorrência deste fenômeno após a cicatrização de enxertos gengivais livres entre o período de um mês a um ano pós-operatório. O presente trabalho tem como objetivo relatar um caso clínico de enxerto gengival livre com acompanhamento longitudinal de 14 anos.

The free gingival graft is a mucogingival procedure preferentially indicated to create keratinized gingival and sometimes could also happen the radicular coverage of the nude roots. The "creeping attachment" is a phenomenon described as the postoperative migration of the gingival marginal tissue in coronal direction, thus, it is considered as a positive event in the sense of obtaining an additional gain of keratinized tissue in the involved area. Longitudinal studies have been showing a larger occurrence of this phenomenon after the free gingival grafts cicatrization among the postoperative period of one month to one year. The objective of the present study is to report a clinical case of free gingival graft with a 14 years longitudinal follow-up.

Influence of cyclosporin A on quality of bone around integrated dental implants: a radiographic study in rabbits.

OBJECTIVES: To evaluate the influence of cyclosporin A (CsA) administration on bone around integrated dental implants assessed by a bone quality index and by quantitative subtraction radiography. MATERIAL AND METHODS: A total of 36 machine surface commercial implants were placed in 18 adult rabbits. After a 3-month healing period without any disturbance, the animals were randomly divided into three groups of six animals each. Group A was sacrificed at this time. CsA was injected subcutaneously in an immunosuppressive dose of 10 mg/kg/day in a test group (Group T), and a Group B served as a control, receiving only vehicle. After 3 months of cyclosporin administration, the animals of both Groups B and T were sacrificed. Radiographs were obtained at implant surgery and at the day of sacrifice with a CMOS sensor. Bone quality around the implants was compared between the groups using a bone quality index and quantitative subtraction radiography. RESULTS: The bone analysis showed that in Group T, the bone quality changed dramatically from a dense cortical to a loose trabecular bone structure (P<0.0001, chi(2) test) while in Groups A and B there were no significant differences. Quantitative digital subtraction radiography showed significantly (P<0.05) lower gray shade values (radiographic density) in a region of bone formation around the implants in Group T (118+/-12) than in Groups A (161+/-6) and B (186+/-10). CONCLUSION: Within the limits of this study, CsA administration has a negative effect on the quality of bone around integrated dental implant.