Effect of different thread configurations on hydrophilic implant stability. A split-mouth RCT.

This split-mouth randomized controlled trial aimed to evaluate the primary and secondary stability of hybrid implants with different thread configurations and hydrophilic surfaces. Twenty patients with a partially edentulous maxilla were selected. These patients received two types of implants with the same hydrophilic surface: CTP group: Cylindrical-Tapered implant with perforating threads; CTH: Cylindrical-Tapered implant with hybrid threads configuration (perforating and condensing threads). The primary and secondary stability parameters were measured by insertion torque and resonance frequency analysis at the time of implant placement and 7, 28, 56, and 90 days after the surgical procedure. The paired t-test was used to compare the data on the implant's stability between the groups. The statistical analysis was performed with a confidence level set at 95%. It was found that the implants in the CTH group presented higher primary stability values ​​at the time of implant placement, due to the higher ISQ (63.61 ± 9.44 vs. 40.59 ±7.46) and insertion torque (36.92 ± 16.50 Ncm vs. 28.00 ± 14.40 Ncm), than the implants in the CTP group. The CTH group presented higher ISQ values ​​in all follow-up periods: 7 days (68.67 ± 7.60 vs. 41.55 ± 9.07), 28 days (68.61 ± 5.98 vs. 47.90 ±13.10), 56 days (74.09 ± 3.96 vs. 55.85 ± 13.18), and 90 days (75.45 ± 4.02 vs. 63.47 ± 6.92) after implant placement. Hybrid implants with perforating and condensing threads demonstrated greater stability than hybrid implants with only perforating threads.

Effect of different thread configurations on hydrophilic implant stability. A split-mouth RCT

Abstract This split-mouth randomized controlled trial aimed to evaluate the primary and secondary stability of hybrid implants with different thread configurations and hydrophilic surfaces. Twenty patients with a partially edentulous maxilla were selected. These patients received two types of implants with the same hydrophilic surface: CTP group: Cylindrical-Tapered implant with perforating threads; CTH: Cylindrical-Tapered implant with hybrid threads configuration (perforating and condensing threads). The primary and secondary stability parameters were measured by insertion torque and resonance frequency analysis at the time of implant placement and 7, 28, 56, and 90 days after the surgical procedure. The paired t-test was used to compare the data on the implant's stability between the groups. The statistical analysis was performed with a confidence level set at 95%. It was found that the implants in the CTH group presented higher primary stability values ​​at the time of implant placement, due to the higher ISQ (63.61 ± 9.44 vs. 40.59 ±7.46) and insertion torque (36.92 ± 16.50 Ncm vs. 28.00 ± 14.40 Ncm), than the implants in the CTP group. The CTH group presented higher ISQ values ​​in all follow-up periods: 7 days (68.67 ± 7.60 vs. 41.55 ± 9.07), 28 days (68.61 ± 5.98 vs. 47.90 ±13.10), 56 days (74.09 ± 3.96 vs. 55.85 ± 13.18), and 90 days (75.45 ± 4.02 vs. 63.47 ± 6.92) after implant placement. Hybrid implants with perforating and condensing threads demonstrated greater stability than hybrid implants with only perforating threads.

Resumo O objetivo deste estudo controlado randomizado de boca dividida foi avaliar a estabilidade primária e secundária de implantes híbridos com diferentes configurações de rosca e superfícies hidrofílicas. Vinte pacientes com maxila parcialmente edêntula foram selecionados. Esses pacientes receberam dois tipos de implantes com a mesma superfície hidrofílica: Grupo CTP: Implante cilíndrico-cônico com roscas perfurantes; Grupo CTH: Implante cilíndrico-cônico com roscas perfurantes e condensadoras. Os parâmetros de estabilidade primária e secundária foram medidos por análise de torque de inserção e frequência de ressonância no momento da colocação do implante e 7, 28, 56 e 90 dias após o procedimento cirúrgico. O teste t-pareado foi utilizado para comparação dos dados de estabilidade entre os grupos. A análise estatística foi executada levando-se em consideração um nível de confiança de 95%. Constatou-se que os implantes do grupo CTH apresentaram maiores valores de estabilidade primária no momento da colocação do implante, devido ao maior ISQ (63.61 ± 9.44 vs. 40.59 ±7.46) e torque de inserção (36.92 ± 16.50 Ncm vs. 28.00 ± 14.40 Ncm), do que os implantes do grupo CTP. Implantes do grupo CTH apresentaram valores de ISQ superiores em todos os períodos de acompanhamento: 7 dias (68.67 ± 7.60 vs. 41.55 ± 9.07), 28 dias (68.61 ± 5.98 vs. 47.90 ±13.10), 56 dias (74.09 ± 3.96 vs. 55.85 ± 13.18) e 90 dias (75.45 ± 4.02 vs. 63.47 ± 6.92). Os implantes híbridos com roscas perfurantes e condensantes demonstraram maior estabilidade do que os implantes híbridos com apenas roscas perfurantes.

Effectiveness of Hyaluronic Acid Injection for Interdental Papillae Recovery in Esthetic Areas: A Randomized Clinical Trial.

The aim of this study was to evaluate the effectiveness of hyaluronic acid (HA) injections used to reduce defects in the gingival papillae in esthetic areas. This randomized study included six patients requiring black triangle treatment in 19 defective papillae. After local anesthesia, less than 0.2 mL of HA was injected 2 to 3 mm into the tip of the deficient papilla in the apical direction. Analysis of the target regions with standardized photographs and 3D intraoral scanning (CEREC 4.5 software with RST files, Dentsply Sirona) was performed at baseline (T0) and at 1 month (T1), 2 months (T2), 3 months (T3), and 4 months (T4) after the initial application of HA. At each time period, the photographic analysis showed no statistically significant differences in linear tissue gain after HA gel application. The 3D analysis showed improvements in the vertical papillae tissue recovery at T3 (0.41 ± 0.21 mm) and T4 (0.38 ± 0.21 mm) when compared to T1 (0.13 ± 0.08 mm; P < .0001). Regarding the reconstruction of the interdental papillae, the general dimensions of the tissue in the black triangle areas showed a significant increase in size percentage at T3 (58% ± 32.9%) compared to T1 (30.41% ± 23.4%; P = .0054). Thus, the application of injectable HA was effective for filling papillae in the esthetic area. Int J Periodontics Restorative Dent 2023;43:e73-e80. doi: 10.11607/prd.5814.

Assessment of Deviations of Implants Installed with Prototyped Surgical Guide and Conventional Guide: In Vitro Study.

OBJECTIVE: The study aimed to assess the angular and linear deviations of implants installed in mannequins aided by surgical guides produced with the techniques of dual tomography (DT), model-based tomography (MT), and nonprototyped guide. MATERIALS AND METHODS: Implants were installed in mannequins of a partially edentulous maxilla and divided into three groups: Group C (n = 20), implants installed using the conventional technique with flap opening and conventional guide; Group DT (n = 20), implants installed using guided surgery with the dual tomography technique; and Group MT (n = 20), implants installed using the model-based tomography technique. After implant installation, the mannequin was subjected to a computed tomography (CT) to measure the linear and angular deviations of implant positioning relative to the initial planning on both sides. RESULTS: There was a higher mean angular deviation in group C (4.61 ± 1.21, p ≤ 0.001) than in groups DT (2.13 ± 0.62) and MT (1.87 ± 0.94), which were statistically similar between each other. Similarly, the linear deviations showed group C with the greatest discrepancy in relation to the other groups in the crown (2.17 ± 0.82, p = 0.007), central (2.2 ± 0.77, p = 0.004), and apical (2.34 ± 0.8, p = 0.001) regions. CONCLUSION: The techniques of DT and MT presented smaller angular and linear deviations than the conventional technique with the nonprototyped guide. There was no difference between the two-guided surgery techniques.

Rehabilitation of a patient diagnosed with Ectodermal Dysplasia presenting hypodontia: a case report

Purpose: The study showed a patient with Ectodermal Dysplasia (ED) who was treated with implants and fixed dental prosthesis by a multidisciplinary team. Case Report: Acrylic resin dental prostheses were designed as long-term provisionals, which allowed modifications when required. After imaging and treatment planning, four implants were placed in the inter-foramenal area of the mandible and 2 years later the definitive prosthesis was fitted. In a second phase, the patient received a combination of autogenous and allogeneic bone grafts in the maxilla. The autogenous graft was removed from the retro-molar region in the mandible. He also received a fixed dental prosthesis supported by 4 implants on the position of the upper canines and second pre-molars. Conclusion: Patient reports successful outcomes and despite the long treatment, patient states is confident with his appearance and speaking improvement. Follow-up was done every six months, for 10 years, and showed encouraging post-treatment outcomes.

Comparative Evaluation of Implants with Different Surface Treatments Placed in Human Edentulous Mandibles: A 1-Year Prospective Study.

The aims of this study were to analyze prospectively and comparatively the peri-implant bone crest levels, bone density, stability and success rate of implants with different surface treatments in human edentulous mandibles. Twenty edentulous patients were selected. Four different implants were placed between the mental foramen. Four groups were evaluated: (1) laser-modified surface (LASER), (2) surface modified by laser with deposition of apatites (LASER + HA), (3) surface modified by double acid etching (ACID, Implacil De Bortoli) and (4) surface modified by sandblasting and acid etching (SLActive®, Straumann). Clinical, radiographic, resonance frequency and tomographic analyses were used. After 4 months, mandibular fixed implant prostheses were installed. Clinical and radiographic analyses were performed at times T0 (immediately after implant placement), T1 (15 days), T2 (30 days), T3 (60 days), T4 (90 days), T5 (120 days), T6 (180 days) and T7 (360 days), post-implant placement. The resonance frequency analysis (RFA) was measured at T0, T4, T6 and T7. The tomographic analysis was performed at T0, T4 and T7. In the radiographic bone density analysis, a statistical difference was found between the SLActive® and LASER + HA groups at T4 (p < 0.05). Statistical differences were observed in RFA at T4 (90 days), between the SLActive® and LASER groups (p < 0.05) and between the SLActive® and LASER + HA groups (p < 0.05). At T6 and T7, statistical differences were found between the SLActive® group and all other implant surfaces (p < 0.01). The experimental surfaces analyzed showed encouraging positive outcomes compared to those of the SLActive® surface. Long-term follow-up should be performed to confirm these results.

Evaluation of deviation in implants placed at different depths with a prototype surgical guide: an in vitro study.

The aim of this study was to measure the angular and linear deviations between planned and placed dental implant positions at different depths in an in vitro model. Ten dental manikins of a maxilla without the central and lateral incisors were used. The implants were placed in the tooth positions using a prototype guide based on computed tomographic scans of dental casts. The groups consisted of implants placed at varying depths according to tooth position: 1 mm deep for the right lateral incisor, 2 mm deep for the right central incisor, 3 mm deep for the left central incisor, and 4 mm deep for the left lateral incisor (n = 10 per group). After implant placement, the manikin was scanned again to compare the positioning of the implants to the planned positions. Statistical analysis evaluated the linear deviations between planned and placed implant positions at 3 points (coronal, central, and apical) as well as the angular discrepancies. The analysis showed that the depth of the implant placement proportionally affected the linear deviation of the actual position from the planned position; thus, the deeper implants showed significantly greater linear deviations (P < 0.05; 1-way analysis of variance and Tukey test). There were no statistically significant differences in the mean angular deviations of the groups. Thus, the results suggest that implants placed at greater depths present greater linear deviations than implants placed at shallower depths, but the angular deviation is not affected by implant depth.

Stability of mandibular implants with Morse taper and external hexagon connections placed under immediate loading: a longitudinal clinical study.

The aim of this study was to compare the longitudinal stability of implants with Morse taper and external hexagon connections placed in the anterior mandible and subjected to immediate functional loading. Nine patients each received 4 mandibular implants placed between the mental foramina. In each patient, 2 implants on the left side of the arch had Morse taper prosthetic connections, and 2 implants on the right side had external hexagon prosthetic connections. Mandibular overdentures and opposing removable complete dentures were placed within 72 hours after implant surgery. Clinical evaluation of the implants via magnetic transduction resonance frequency analysis was performed immediately following surgery and 3 months, 6 months, and 2 years following surgery to obtain the implant stability quotient (ISQ). The data obtained were parametric according to the Kolmogorov-Smirnov normality test. The lowest ISQ of any implant was approximately 67, representing reliable osseointegration. The only statistically significant difference between the 2 types of prosthetic connection was found in the initial period (immediately following surgery), when the external hexagon connection in the distal position presented greater stability than did the Morse taper connection in the same position on the opposite side (P < 0.05; Student t test). In intragroup comparisons, no statistically significant differences were found regarding the positions of the implants in the mandible. When the different follow-up periods were evaluated, there were statistically significant differences only in the external hexagon group, with significant reductions in stability of both mesial and distal implants at 6 months compared to other time periods (P < 0.05; Tukey test). Within the limitations of the study, it can be concluded that both Morse taper and external hexagon prosthetic connections provide good stability in an immediate functional loading protocol.

Linear dimensional accuracy of stereolithographic surgical guide after chemistry and physics sterilization.

OBJECTIVES: The purpose of this study was to evaluate the dimensional stability of prototyped surgical guides after autoclave and 2% glutaraldehyde sterilization processes. MATERIAL AND METHODS: Twenty prototyped surgical guides were prepared and submitted to two sterilization processes (n = 10): Physics - sterilization by autoclave (saturated water vapor under pressure, temperature of 126 to 130 °C, pressure of 1,7 at 1.9 kgf/cm2, 16 min); Chemistry - sterilization by 2% glutaraldehyde for 10 h. Six pre-established points were measured in the prototyped surgical guides, before and after sterilization, using a digital caliper rule. The comparisons were made using orthogonal contrasts using the linear model of mixed effects (random and fixed). RESULTS: there are no significant differences between autoclave and glutaraldehyde 2% (p>0.05) there are significant differences after autoclave sterilization (p<0.05) and there are not significant differences after 2% glutaraldehyde sterilization (p>0.05). CONCLUSION: autoclave promoted dimensional alteration of the prototyped surgical guides, and the chemical sterilization by glutaraldehyde 2% did not cause dimensional alteration of the prototype surgical guides, being a favorable choice for sterilization. CLINICAL SIGNIFICANCE: the sterilization of surgical guides can be performed through the chemical process with 2% glutaraldehyde without changing the linear precision of the prototype surgical guides.

Survival of short dental implants in atrophied jaw: a systematic review

AIM: Short implants are manufactured for use in atrophic regions of the jaw. Therefore, the current does not sufficiently reveal a direct correlation between the impact of implant length on implant survival. The purpose of this systematic review was to compile the evidence of short implant survival in atrophied jaws. METHODS: Electronic and manual literature searches were performed by two independent reviewers in several databases, including MEDLINE, EMBASE, and Cochrane Oral Health Group Trials Register, for articles up to September 2015 using the following terms in some combinations: "short implant", "mandible/atrophied jaws", and "implant survival/ survival rate/ survival analysis". RESULTS: The 19 included studies present in average 5.5 years (range 1.0-20.0 years) follow-up and 96.1% (range 73.4-100.0 percent) survival rate of the short implants in atrophied mandibular. CONCLUSIONS: This systematic review found evidences regarding to safety of short implant placement in atrophied jaws although stronger evidence is essential to confirm this finding.

Hyaluronic acid for repairing interdental papilla in esthetic area: case report

ABSTRACT: Background: Hyaluronic acid is a treatment option for this deficiency gingival papilla, since it aims to increase tissue volume in the region of loss of interdental papilla, minimally invasive. Aim this study was to describe the application of Hyaluronic acid in a deficient gingival papilla. Case report: Patient presented absence of interdental papilla in the maxillary arch around upper anterior teeth. A comprehensive exam was performed, plus 2D photographs taken with a professional camera coupled to a device for image standardization, and an intraoral scanning with the OMNICAM scanner. Three applications of Hyaluronic acid were performed to fill the black spaces, at an interval of four weeks. The patient was followed-up for three months, and the recovery of papilla was observed. Conclusion: The Hyaluronic acid as gingival filling material can be considered as a treatment option for augmenting interdental papilla in aesthetic area.

Human non-decalcified histology of three dental implants 45 months under function-a case report.

BACKGROUND: Fracture of an implant is a quite rare event but represents an important opportunity to evaluate the peri-implant bone tissue response to implant overload in human beings. This study aimed to evaluate bone tissue around three fractured titanium implants retrieved from a human maxilla, by histomorphometric and birefringence analyses. CASE REPORT: For this, the implants and the surrounding bone were removed after having been united to a tooth in function for 45 months, by a 4-mm internal diameter trephine bur, following an undecalcified section was obtained. The results showed a rate of 77.3% of bone-to-implant contact (BIC) and 80.3% of bone area filling within the limits of the implant threads. Under circularly polarized light microscopy investigation, the amount of the transverse collagen fibers was of 48.11%, and the amount of the longitudinal collagen fibers was of 51.89%. CONCLUSION: Within the limitation of this study, the possible cause of the implant fracture could be the association of overload, inadequate implant diameter, and fragile internal hexagon connection.

Analysis of Linear and Angular Deviations of Implants Installed With a Tomographic-Guided Surgery Technique: A Prospective Cohort Study.

The aim of this study was to evaluate the linear and angular deviations of the implants installed by the computerized tomography (CT)-guided surgery technique. Eighteen patients who underwent implant insertion by means of CT-guided surgery participated in this study. Ten of these patients had a fully edentulous maxilla, and 8 had a fully edentulous mandible. The patients received a total of 115 implants, of which 81 implants were installed in the maxilla and 34 installed in the mandible. Tomographic guides were made for tomographic examination in both the upper and lower jaws. After the image acquisition, the virtual planning of the positioning of the implants was performed in relation to the previously made prosthesis. The measurement of the linear and angular deviations between the virtual planning and the final position of the implants was performed with the overlap of the planning and postoperative tomography. There were no differences in the linear and angular deviations of the implants installed in the maxilla and mandible. Compared with the coronal region, there was a trend of greater linear deviations in the apical regions of the implants and a greater tendency toward deviations in the posterior regions than in the anterior regions of both arches. The CT-guided surgery promoted the installation of implants with high accuracy and allowed the installation of straight pillars in all cases evaluated. The linear deviations were not different in the different regions of the mouth or in the different portions of the implants.

Semiautomatic device for in vitro/ experimental bone perforation in dental implant research.

PURPOSE: The present study presents a semiautomatic device developed to perform in vitro experiments using surgical drills for assisting dental implant research. It was built to perform tests independent of human direct contact, and contains an adjustable toolholder for engaging different types of implant contra angle hand pieces, in which different drills can be adapted. The researcher is able to make a range of adjustments on the machine, such as controlling the drilling force and depth. MATERIALS AND METHODS: The device was tested on samples of both synthetic and natural bone with type I density, and a sequence of drills selected to perform the perforations. Drilling time and perforation force exerted during drilling were evaluated, as both parameters are required to be standardized. RESULTS: It was observed that the drilling performed using the device was uniform using both types of bone, although the drilling time for the synthetic bone was higher. All perforations were exactly on the spot previously determined, and without variations in drill angulations. The perforation force was higher for the lance pilot drill for both bone types, and the natural bone required a higher axial force than the synthetic bone. CONCLUSION: Thus, we consider this device trustable to perform standardized analysis and provide accurate results. It can be used for tests performed in universities and companies that develop dental implant materials and products.

Avaliação da estabilidade primária de implantes curtos e convencionais instalados em ossos de diferentes densidades / Evaluation of primary stability of short and conventional implants in bones with different densities

O objetivo deste estudo foi avaliar a estabilidade primária de implantes curtos e convencionais instalados em ossos com densidades tipo I e tipo IV de origem sintética e natural. Implantes nos tamanhos (Diamêtro x Comprimento) 3,75 x 13 mm, 3,75 x 10 mm, 4,3 x 5,5 mm e 5 x 5,5 mm foram instalados em blocos ósseos seguindo uma sequência de fresagens e avaliados o torque de inserção e o coeficiente de estabilidade primária (CE) através da análise da frequência de ressonância (AFR). Os resultados mostraram que implantes de diferentes tamanhos e ossos de diferentes densidades e origens influenciam tanto nos valores de torque de inserção quanto de AFR (p<0.05). Todos os implantes instalados nos ossos tipo IV apresentaram menores torques de inserção e menores CE (p<0.05) comparados aos instalados nos ossos tipo I, e implantes curtos apresentaram maiores torques que os convencionais intalados no osso tipo I. Assim, a utilização de implantes curtos pode ser uma alternativa viável de tratamento, principalmente em sítios ósseos com maiores densidades (AU).

The aim of this study was to assess the primary stability of short and conventional implants placed in bone with type I and type IV densities of synthetic or natural origin. Implants (D x C) of 3.75 x 13 mm, 3.75 x 10 mm, 4.3 x 5.5 mm, and 5 x 5.5 mm were placed in bone blocks following a drilling sequence and assessment of insertion torque and primary stability coefficient (SC) through resonance frequency analysis (RFA). The results showed that implants of different sizes and bones of different densities and origins influence both insertion torque and RFA values (p <0.05). All implants placed in type IV bones presented lower insertion torques and lower SC (p <0.05) compared to those placed in type I bones, and short implants presented higher torques than conventional implants in type I bone. So the use of short implants may be a viable treatment alternative, mainly in bone areas with higher densities (AU).

Um novo conceito na obtenção do guia prototipado em Implantodontia ­ relato de caso / A newconcept in prototyped guide obtaining in implantology - case report

A tomografia computadorizada (TC) em Implantodontia permite planejar virtualmente a posição ideal do implante dentário considerando as características anatômicas e restauradoras. Através desse planejamento, o guia cirúrgico prototipado pode ser confeccionado possibilitando a integração dos determinantes protéticos no posicionamento dos implantes. Nesse contexto, a "técnica da tomografia do molde" para obtenção do guia prototipado consiste na realização da TC do molde do paciente que será vazado virtualmente para a obtenção de um modelo 3D, capaz de reproduzir tecidos moles e elementos dentais. Posteriormente, essa imagem é virtualmente sobreposta à tomografia da boca do paciente, permitindo uma avaliação óssea conjunta com o tecido mole e elementos dentais ausentes. O relato de caso descreve a reabilitação oral com implantes osseointegráveis utilizando um guia prototipado confeccionado através da "técnica da tomografia do molde". Paciente apresentava ausência dos dentes 17, 16, 14, 12, 11, 21, 22 e 26. Devido à presença de qualidade e quantidade óssea adequadas, foi planejada a reabilitação das áreas edêntulas com implantes dentários posicionados utilizando guia prototipado confeccionado pela "técnica da tomografia do molde". Após a obtenção do guia, os implantes dentários foram posicionados. Com a instalação dos provisórios, após 4 meses de osseointegração, constatou-se que a realização da cirurgia guiada com a utilização do guia prototipado obtido através da "técnica da tomografia do molde" garantiu previsibilidade no posicionamento dos implantes dentários trazendo facilidade na execução das próteses, além de sucesso estético/funcional no tratamento restaurador e maior comodidade ao paciente do início ao final do tratamento (AU).

The computed tomography (CT) in implant Dentistry allows virtually plan of the dental implant ideal position considering restorative and anatomical characteristics. Through this planning, a surgical guide can be prototyped for integrate prosthetic aspects in the positioning of the implants. In this context, the "mold tomography technique" for obtaining prototyped guide consists in use the CT of the patient mold to be poured virtually for obtaining a 3D model capable of reproducing soft tissues and dental elements. Then, this image is superimposed on the virtual scan of the patient's mouth, allowing a complete evaluation of bone and soft tissues. This case report describes the oral rehabilitation with dental implants using a prototyped guide made by "mold tomography technique." Patient had no 17, 16, 14, 12, 11, 21, 22, and 26 teeth. Due to the presence of quality and adequate bone quantity, it was planned rehabilitation of edentulous areas with dental implants positioned using prototyped guide made by "mold tomography technique." After obtaining the guide, dental implants were positioned. After 4 months of osseointegration, the final restaurations have been installed. With the installation of the provisory, after 4 months of osseointegration, it has noted that the realization of guided surgery using the guide prototyped obtained by "mold tomography technique" guaranteed predictability in the placement of dental implants bringing ease of application of the prosthesis beyond aesthetic / functional success in restorative treatment and convenience to the patient from beginning to end of treatment (AU).

Some aspects of bone remodeling around dental implants

ABSTRACT: Considering that success of dental implants is not only related to osseointegration, but also with their survival rates, the aim of this study was to perform a literature review about bone remodeling around osseointegrated implants. A detailed search strategy was used for this, and articles published between the years 1930 and 2012 were selected. The rare data found in the literature demonstrated that implants are osseointegrated 30 days after their placement. However, active bone remodeling with osteoclasts and osteoblasts working in synchrony continues to occur. Therefore, after osseointegration, the initially formed bone, which presents characteristics of spongy bone, is gradually resorbed and replaced by compact bone after 90 days. Furthermore, other portions of bone tissue a little more distant from the interface, which establish direct contact with the implant, are also damaged during the drilling process, and therefore, they also need to be remodeled. Among the rare studies found in the literature about bone remodeling after osseointegration, there were no verified studies on the possible influence of implant surface treatments on bone remodeling that occurs after osseointegration. Only studies involving implants with machined surfaces have been conducted up to now.

Evaluation of Short and Regular Implants after Prosthesis Placement in the Mandible: A Nonrandomized Controlled Clinical Trial.

AIM: The aim of this nonrandomized controlled preliminary clinical trial was to compare treatment using short and conventional implants in the posterior region of the mandible after prosthesis installation by means of clinical, resonance frequency, and radiographic analyses. MATERIALS AND METHODS: A total of 10 patients with 40 dental implants already installed were included in this study. Four implants were installed for each subject, in which the length of the implants (short and conventional) was distributed according to the reminiscent alveolar bone in the left and right side of the mandible. All implants received splinted prosthesis after the osseointegration period. Analyses were performed immediately after prosthesis installation (T1), and 3 (T2) and 6 months (T3) after prosthesis placement. RESULTS: The 6-month survival and success rates were 100% for the short and conventional implants. Probing depths (PDs) after 6 months did not show statistical differences between short and conventional implants. All groups showed mean implant stability quotient (ISQ) values above 60 in all periods evaluated, demonstrating great implant stability, and no differences were found between groups at T3. Radiographic measurements showed an increased bone loss for conventional implants compared with short implants in all the three periods evaluated. CONCLUSION: Our findings suggest that treatment of resorbed posterior regions in the mandible with shorter dental implants is as reliable as treatment with conventional implants after 6 months of splinted prosthesis installation. CLINICAL SIGNIFICANCE: Short implants might be considered a predictable treatment alternative to bone augmentation or extensive surgical techniques in regions of restricted vertical bone height in the posterior region of the mandible.

Clinical comparison of short and conventional implants placed in the posterior region of the mandible. A pilot study / Comparação clínica de implantes curtos e convencionais instalados na região posterior da mandíbula. Estudo piloto

Objective: To evaluate and correlate the values of radiographic bone density, peri-implant bone height and resonance frequency analysis (RFA) of short or conventional implants placed in the posterior region of the mandible after installing a prosthesis. Material and method: Eleven patients were selected for this prospective parallel pilot study. The prostheses were supported by two types of implants: short implants (n = 18) (5.0 x 5.5 mm and 5.0 x 7.0 mm) and conventional implants (n = 23) (4.0 x10 mm and 4.0 x 11.5 mm). The implants were evaluated by RFA, by measuring the bone height, and peri-implant bone density. The implants were evaluated at the periods T0 (immediately after installation of the prosthesis), T1 (after 90 days), and T2 (after 180 days). Result: There were no statistically significant differences between groups with respect to radiographic bone density (152.50 ± 15.39 vs. 157.60 ± 28.46, for conventional and short implants, respectively at T2), stability of the implants (Conventional implants: 66.76 ± 10.39 at T0, and 61.85 ± 8.38 at T2 vs. Short implants: 57.50 ± 12.17 at T0, and 61.53 ± 7.39 at T2) and peri-implant bone loss (0.03 mm vs.-0.17 mm, for conventional and short implants, respectively at T2). Additionally, a significant correlation between the evaluated parameters was not detected. Conclusion: The short and conventional implants presented similar stability, bone level and density after the activation of occlusion loading.

Objetivo: Avaliar e correlacionar os valores de densidade óssea radiográfica, altura óssea peri-implantar e de frequência de ressonância nos implantes curtos e convencionais instalados na região posterior da mandíbula após a instalação da prótese provisória. Material e método: Esse estudo piloto clínico prospectivo contou com a participação de 11 pacientes que foram divididos previamente em dois grupos: implantes curtos (n=18) (5,0 x 5,5 mm e 5,0 x 7,0 mm) e implantes convencionais (n=23) (4,0 x 10 mm e 4,0 x 11,5 mm). Foram executadas análise da frequência de ressonância, altura óssea e densidade óssea peri-implantar. Os implantes foram avaliados nos períodos T0 (imediatamente após a instalação do provisório), T1 (após 90 dias) e T2 (após 180 dias). Resultado: Não houve diferenças estatisticamente significativas entre os grupos com relação a densidade óssea radiográfica (152,50 ± 15,39 vs. 157,60 ± 28,46, para implantes convencionais e curtos respectivamente no período T2), estabilidade dos implantes (Implantes convencionais: 66,76 ± 10,39 no período T0 e 61,85 ± 8,38 no período T2 vs. Implantes curtos: 57,50 ± 12,17 no período T0 e 61,53 ± 7,39 no período T2) e quanto a perda óssea periimplantar (0,03 mm vs. -0,17 mm, em implantes convencionais e curtos no período T2, respectivamente). Adicionalmente a isso, não foram detectados correlação significativa entre densidade radiográfica com altura óssea peri-implantar e nem com a frequência de ressonância. Conclusão: Verificou-se que os implantes curtos apresentaram um comportamento semelhante aos implantes de comprimento convencionais com relação à frequência de ressonância, a densidade radiográfica peri-implantar e a manutenção dos níveis ósseos periimplantares.

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.