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Implant Installation (implant + installation)
Selected AbstractsAccuracy assessment of computer-assisted flapless implant placement in partial edentulismJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 4 2010N. Van Assche Van Assche N, van Steenberghe D, Quirynen M, Jacobs R. Accuracy assessment of computer-assisted flapless implant placement in partial edentulism. J Clin Periodontol 2010; 37: 398,403. doi: 10.1111/j.1600-051X.2010.01535.x Abstract Aim: To assess the accuracy of implants placed flapless by a stereolithographic template in partially edentulous patients. Material and Methods: Eight patients, requiring two to four implants (maxilla or mandible), were consecutively recruited. Radiographical data were obtained by means of a cone beam or a multi-slice CT scan and imported in a software program. Implants (n=21) were planned in a virtual environment, leading to the manufacture of one stereolithographic template per patient to guide the implant placement in a one-stage flapless procedure. A postoperative cone beam CT was performed to calculate the difference between virtual implant (n=21) positions in the preoperative planning and postoperative situation. Results: A mean angular deviation of 2.7° (range 0.4,8, SD 1.9), with a mean deviation at the apex of 1.0 mm (range 0.2,3.0, SD 0.7), was observed. If one patient, a dropout because of non-conformity with the protocol, was excluded, the angular deviation was reduced to 2.2° (range 0.6,3.9, SD 1.1), and the apical deviation to 0.9 mm (range 0.2,1.8). Conclusion: Based on this limited patient population, a flapless implant installation appears to be a useful procedure even when based on accurate and reliable 3D CT-based image data and a dedicated implant planning software. [source] Bone reactions to longstanding functional load at implants: an experimental study in dogsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 9 2005T. Berglundh Abstract Objectives: The aims of the present investigation were (i) to study marginal bone level alterations following implant installation, abutment connection and functional loading and (ii) to analyse bone tissue reactions to functional load. Material and Methods: Six beagle dogs, about 1-year old, were used. All mandibular pre-molars were extracted. Three months later four implants of the Astra Tech Implants® Dental System were installed in one side of the mandible and four standard fixtures of the Brånemark System® were placed in the contralateral side of the mandible. Abutment connection was performed 3 months later and a plaque control programme was initiated. Three months after abutment connection fixed partial dentures (FPDs) made in gold were cemented to the maxillary canines and pre-molars. FPDs were also connected to the three posterior implants in each side of the mandible, while the mesial implant in each side was used as an unloaded control. Radiographs were obtained from all implant sites following implant installation, abutment connection and FPD placement. Ten months after the FPD placement the radiographic examination was repeated. The animals were sacrificed and biopsies from all implant sites were obtained and prepared for histological analysis. Results: The radiographic analysis revealed that largest amount of bone loss occurred following implant installation and abutment connection and that this loss was more pronounced at Brånemark than at Astra implants. The bone level alterations that were observed at implants exposed to 10 months of functional load in both implant systems were small and did not differ from control sites. The histological analysis revealed that implants exposed to functional load exhibited a higher degree of bone-to-implant contact than control implants in both implant systems. Conclusion: It is suggested that functional load at implants may enhance osseointegration and does not result in marginal bone loss. [source] Patient evaluation of treatment with fixed implant- supported partial denturesJOURNAL OF ORAL REHABILITATION, Issue 11 2001S.-W. Yi The aim of this study was to analyse the patient evaluation of functional treatment outcome in 40 periodontally compromised patients who received implant-supported prostheses (ISPs) as part of the total treatment. The treatment protocol comprised periodontal treatment, extraction of teeth with poor prognosis, placement of dental titanium implants, and after healing, insertion of fixed ISPs. Five of the patients became edentulous in one jaw after extraction of all teeth and received a complete ISP, whereas 35 patients became partially edentulous after extraction of some teeth, 12 receiving a partial ISP on , 3 implants, and 23 one on two implants. The follow-up period was on average 1,8 years after the connection of the prostheses, which provided the patients a dentition with a mean of 12 occluding dental units. The first author (S.-W. Yi) performed all implant treatment. Patients' opinions on oral functions , mastication, phonetics, oral hygiene, chewing comfort and aesthetics , were evaluated by means of a questionnaire both before implant installation and at the last follow-up. A control group of 30 subjects with a healthy dentition of 14 occluding natural pairs of teeth answered the same questionnaire on one occasion. A great majority of the patients were extremely satisfied with the oral function after treatment and experienced the ISPs as ,natural teeth'. There was no significant difference between the three treatment groups and the control group for mastication, phonetics, chewing comfort and aesthetics. Patients with ISPs reported a small but significantly greater difficulty with oral hygiene procedures than the controls with natural teeth. Most patients said that they would undergo the treatment again, if necessary, and recommend it to others. It was concluded that the rehabilitation of the periodontally compromised patients, including ISPs on osseointegrated dental titanium implants, resulted in subjectively improved and satisfactory oral function. [source] Implant Placement in Patients with Oral Bisphosphonate Therapy: A Case SeriesCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2010Ghasem Omati Shabestari DDS ABSTRACT Background: Although the effect of bisphosphonates on dental implant osseointegration is not clear, dental implant failures attributable to oral bisphosphonate therapy have been reported in patients with osteoporosis. Purpose: The aim of this study was to evaluate implant survival in patients with a history of bisphosphonate therapy in a retrospective survey. Materials and Methods: A total of 46 ITI implants placed in 21 osteoporotic patients (females; average age 53 years, range 42,79 years) were evaluated with regard to probing depth, mobility, thread exposure, and bleeding on probing. All patients were under oral bisphosphonate therapy. Results: None of implants showed mobility and all patients could be considered free from peri-implantitis. Time of bisphosphonate therapy before and after implant insertion showed no statistically significant influence on PD, BOP, and TE. Likewise, implant location, prosthetic type, and opposing dentition had no statistically significant influence on the clinical and radiological parameters of implants. Conclusion: Within the limitations of this study, it could be concluded that neither being on oral bisphosphonate treatment before implant placement nor starting bisphosphonate therapy after implant installation might jeopardize the successful osseointegration and clinical and radiographic condition of the implants. [source] Effects of Implant Design and Surface on Bone Regeneration and Implant Stability: An Experimental Study in the Dog MandibleCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2001Lars Rasmusson DMD ABSTRACT Background: Previous experimental studies have shown a higher degree of bone-implant contact for surface-enlarged implants compared with machined implants. Yet, there is insufficient evidence that such implants show higher stability and an increased survival rate. Purpose: The purpose of this investigation was to study the integration and stability of grit-blasted implants with retention elements on the implant neck, with and without marginal bone defects, compared with machined implants without retention elements. Materials and Methods: After tooth extraction of the mandibular premolars in six dogs, two grit-blasted, partly microthreaded Astra Tech implants and one standard Branemark implant were bilaterally placed in each dog. On one side, 3 ± 3 mm large buccal defects were created, to expose three to four implant threads. The contralateral side served as control, and no defects were made. The animals were sacrificed after 4 months of healing. Implant stability was measured using resonance frequency analysis at implant installation and after 4 months of healing. Histologic and histomorpho-metric evaluation was made after 4 months of healing. Results: Resonance frequency analysis indicated that all implants in the test and control groups were osseointegrated after 4 months, with a tendency toward higher implant stability for the Astra Tech implants. There was a statistically significant higher increase in resonance frequency for the Astra test implants compared with their corresponding controls. Histology and histomorphometry showed well-integrated implants with varying degrees of bone repair at the defect sites. The greater bone-implant contact for the Astra implants was statistically significant. No significant difference between the implants in amount of bone filling the threads was recorded. Conclusions: The Astra Tech implants tested showed a higher degree of bone,implant contact and higher level of bone regenerated at defect sites compared with the Brånemark implants. Resonance frequency analysis demonstrated a significantly higher increase in the Astra test implants compared with their control groups than did the Brånemark test implants versus their controls. [source] Early Functional Loading of Brånemark Dental Implants: 5-Year Clinical Follow-up StudyCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2 2000Ingvar Ericsson DDS ABSTRACT Background: Short-term clinical studies have indicated the possibility of one-stage surgery and early loading of machined titanium implants. However, long-term data comparing the outcome to the conventional two-stage technique are missing. Purpose: A clinical and radiographic study was performed to compare the outcome of oral rehabilitation of the endentulous mandible by fixed suprastructures connected to implants installed according to either (1) a one-stage surgical procedure and early loading (experimental group - EG) or (2) the original two-stage concept (reference group - RG). The EG and RG comprised 16 and 11 subjects, respectively. Materials and Methods: The following specific inclusion criterion were adopted: (1) all patients had to consider themselves to be in good general health, (2) the amount of bone had to enable the installation of five to six, at least 10-mm long fixtures (Mk II fixtures; Nobel Biocare AB, Göteborg, Sweden) between the mental foramina, and (3) the patients had to be available for the follow-up and maintenance program. A total of 88 implants were placed in the EG compared to 30 in the RG. In the EG, fixed appliances were connected to the implants within 20 days following implant installation while the fixed appliances in the RG were connected about 4 months following fixture installation. At delivery of the suprastructures, all patients were radiographically examined, an examination that was repeated at the 18- and 60-month follow-ups. Results: The analysis of the radiographs from the EG disclosed that during the observation period, between 18 and 60 months, the mean loss of bone support amounted to 0.2 mm (SD = 0.4). The corresponding value observed in the RG was 0.0 mm (SD = 0.5). During the 60-month observation period, no fixture was lost in any of the two groups examined. The implants under study as well as those in the reference material were at all observation intervals found to be clinically stable. Conclusions: This clinical study demonstrated that it is, at least based on a 5-year observation period, possible to successfully load via a permanent fixed rigid cross-arch suprastructure titanium dental implants soon after installation. However, such a treatment approach has to be strictly limited to the interforamina area of the endentulous mandible. Furthermore, the bone resorption was found to be within the same range around such implants as around implants installed and loaded according to the original two-stage protocal. [source] A prospective, randomized-controlled clinical trial to evaluate bone preservation using implants with different geometry placed into extraction sockets in the maxillaCLINICAL ORAL IMPLANTS RESEARCH, Issue 1 2010Mariano Sanz Abstract Aim: The primary objective of this study was to determine the association between the size of the void established by using two different implant configurations and the amount of buccal/palatal bone loss that occurred during 16 weeks of healing following their installation into extraction sockets. Material and methods: The clinical trial was designed as a prospective, randomized-controlled parallel-group multicenter study. Adults in need of one or more implants replacing teeth to be removed in the maxilla within the region 15,25 were recruited. Following tooth extraction, the site was randomly allocated to receive either a cylindrical (group A) or a tapered implant (group B). After implant installation, a series of measurements were made to determine the dimension of the ridge and the void between the implant and the extraction socket. These measurements were repeated at the re-entry procedure after 16 weeks. Results: The study demonstrated that the removal of single teeth and the immediate placement of an implant resulted in marked alterations of the dimension of the buccal ridge (43% and 30%) and the horizontal (80,63%) as well as the vertical (69,65%) gap between the implant and the bone walls. Although the dimensional changes were not significantly different between the two-implant configurations, both the horizontal and the vertical gap changes were greater in group A than in group B. Conclusions: Implant placement into extraction sockets will result in significant bone reduction of the alveolar ridge. To cite this article: Sanz M, Cecchinato D, Ferrus J, Pjetursson EB, Lang NP, Jan L. A prospective, randomized-controlled clinical trial to evaluate bone preservation using implants with different geometry placed into extraction sockets in the maxilla. Clin. Oral Impl. Res. 21, 2009; 13,21. [source] Immediate functional loading of implants in single tooth replacement: a prospective clinical multicenter studyCLINICAL ORAL IMPLANTS RESEARCH, Issue 8 2008Mauro Donati Abstract Objectives: The aim of the present study was to evaluate the outcome of immediate functional loading of implants in single-tooth replacement using two different installation procedures. Material and Methods: One hundred and fifty-one subjects, who required single-tooth rehabilitation in the area of 15,25 and 35,45, were enrolled in eight private clinics in Italy. The implant sites were randomly allocated to one of the following treatment groups. In the control group, in which a standard preparation procedure for implant placement and submerged healing of the implant was used, abutment connection and loading of the implants were performed 3 months after installation. In the test group 1, a standard preparation procedure for the implant placement and immediate functional loading of implant was carried out. In the test 2 group, however, a modified implant installation procedure (osteotome technique) was used followed by immediate functional loading of the implant. Clinical and radiographic examinations were performed at 3 and 12 months of follow-up at all sites. Results: Three implants (5.5%) from the test 2 group (osteotome preparation) and one (2%) from the test 1 group (conventional drill preparation) failed to integrate and were removed one and three months after implant installation. The mean marginal bone loss assessed at 12 months was 0.31 mm (test 1), 0.25 mm (test 2) and 0.38 mm (control) (no statistically significant differences were found between the three treatment groups.) Conclusion: It is suggested that immediate functional loading of implants that are placed with a conventional installation technique and with sufficient primary stability may be considered as a valid treatment alternative in a single-tooth replacement. [source] Resonance frequency analysis in relation to jawbone characteristics and during early healing of implant installationCLINICAL ORAL IMPLANTS RESEARCH, Issue 3 2007M. A. Huwiler Objectives: To monitor resonance frequency analysis (RFA) in relation to the jawbone characteristics and during the early phases of healing and incorporation of Straumann® dental implants with an SLA surface. Material and methods: 17 Straumann 4.1 mm implants (10 mm) and 7 Straumann 4.8 mm implants (10 mm) were installed and ISQ determined at baseline and after 1, 2, 3, 4, 5, 6, 8 and 12 weeks. Central bone cores were analyzed from the 4.1 mm implants using micro CT for bone volume density (BVD) and bone trabecular connectivity (BTC). Results: Pocket probing depths ranged from 2,4 mm and bleeding on probing from 5,20%. At baseline, BVD varied between 24% and 65% and BTC between 4.9 and 25.4 for the 4.1 mm implants. Baseline ISQ varied between 55 and 74 with a mean of 61.4. No significant correlations were found between BVD or BTC and ISQ Values. For the 4.8 mm diameter implants baseline ISQ values ranged from 57,70 with a mean of 63.3. Over the healing period ISQ values increased at 1 week and decreased after 2,3 weeks. After 4 weeks ISQ values, again increased slightly, no significant differences were noted over time. One implant (4.1 mm) lost stability at 3 weeks. Its ISQ value had dropped from 68 to 45. However the latter value was determined after the clinical diagnosis of instability. Conclusion: ISQ values of 57,70 represented homeostasis and implant stability. However no predictive value for loosing implant stability can be attributed to RFA since the decrease occurred after the fact. [source] Soft and hard tissue assessment of immediate implant placement: a case seriesCLINICAL ORAL IMPLANTS RESEARCH, Issue 2 2007Gintaras Juodzbalys Abstract Objectives: The aim of this prospective study was to evaluate clinically and radiographically the success and esthetic result of immediate implant placement at the time of extraction. Material and methods: Twelve patients with 14 titanium screw-shaped implants (13,16 mm length and 4.3 or 5 mm diameters) were placed in the extraction sockets. Defects after implant placement were recorded, and then filled up with deproteinized bovine bone mineral, bioabsorbable collagen membrane, and absorbable pins. The defect was again re-evaluated at second-stage surgery. Clinical and radiographic parameters of the peri-implant conditions were assessed at the moment of prosthesis placement and at 1-year follow-up. Results: The cumulative implant survival and success rate was 100% after a 1-year observation period. Analysis of the esthetic result showed that the mean pink esthetic score (PES) was 11.1 (SD 1.35) at 1-year follow-up. At 1 year, 64.3% papillae had a score of 2 and the remaining 35.7% score 3 according to the Jemt (1997) papillary index. Optimal value of width of the keratinized mucosa was recorded in 13 (92.9%) implant cases in both periods of follow-up. At 1-year follow-up, the linear distance between implant-shoulder to the bone peaks remains stable with a mean of 2.62±0.2 mm at the mesial and 2.9±0.58 mm at the distal aspect. Conclusion: Careful evaluation of potential extraction sites before immediate implant installation promotes optimal implant esthetics. [source] Modeling of the buccal and lingual bone walls of fresh extraction sites following implant installationCLINICAL ORAL IMPLANTS RESEARCH, Issue 6 2006Mauricio G. Araújo Abstract Objective: To determine whether the reduction of the alveolar ridge that occurs following tooth extraction and implant placement is influenced by the size of the hard tissue walls of the socket. Material and methods: Six beagle dogs were used. The third premolar and first molar in both quadrants of the mandible were used. Mucoperiostal flaps were elevated and the distal roots were removed. Implants were installed in the fresh extraction socket in one side of the mandible. The flaps were replaced to allow a semi-submerged healing. The procedure was repeated in the contra later side of the mandible after 2 months. The animals were sacrificed 1 month after the final implant installation. The mandibles were dissected, and each implant site was removed and processed for ground sectioning. Results: Marked hard tissue alterations occurred during healing following tooth extraction and implant installation in the socket. The marginal gap that was present between the implant and the walls of the socket at implantation disappeared as a result of bone fill and resorption of the bone crest. The modeling in the marginal defect region was accompanied by marked attenuation of the dimensions of both the delicate buccal and the wider lingual bone wall. Bone loss at molar sites was more pronounced than at the premolar locations. Conclusion: Implant placement failed to preserve the hard tissue dimension of the ridge following tooth extraction. The buccal as well as the lingual bone walls were resorbed. At the buccal aspect, this resulted in some marginal loss of osseointegration. [source] Tissue modeling following implant placement in fresh extraction socketsCLINICAL ORAL IMPLANTS RESEARCH, Issue 6 2006Mauricio G. Araújo Abstract Objective: To study whether osseointegration once established following implant placement in a fresh extraction socket may be lost as a result of tissue modeling. Material and methods: Seven beagle dogs were used. The third and fourth premolars in both quadrants of the mandible were used as experimental teeth. Buccal and lingual full-thickness flaps were elevated and distal roots were removed. Implants were installed in the fresh extraction socket. Semi-submerged healing of the implant sites was allowed. In five dogs, the experimental procedure was first performed in the right side of the mandible and 2 months later in the left mandible. These five animals were sacrificed 1 month after the final implant installation. In two dogs, the premolar sites on both sides of the mandible were treated in one surgical session and biopsies were obtained immediately after implant placement. All biopsies were processed for ground sectioning and stained. Results: The void that existed between the implant and the socket walls at surgery was filled at 4 weeks with woven bone that made contact with the SLA surface. In this interval, (i) the buccal and lingual bone walls underwent marked surface resorption and (ii) the height of the thin buccal hard tissue wall was reduced. The process of healing continued, and the buccal bone crest shifted further in the apical direction. After 12 weeks, the buccal crest was located>2 mm apical of the marginal border of the SLA surface. Conclusion: The bone-to-implant contact that was established during the early phase of socket healing following implant installation was in part lost when the buccal bone wall underwent continued resorption. [source] Positive effect of early loading on implant stability in the bi-cortical guinea-pig modelCLINICAL ORAL IMPLANTS RESEARCH, Issue 4 2005Els De Smet Abstract: Loading, early after implant placement, has gained rapid interest in dentistry. Primary implant stability, as e.g. defined by resonance frequency instrumentation, has been isolated as a predicator when immediate and early implant loading is applied. The aim of this study was to investigate the effect of early (after 7 days) mechanical loading on the establishment of osseointegration by means of resonance frequency analysis (RFA). Percutaneous titanium implants were installed in both tibiae of 10 guinea-pigs. One week after implant installation, one implant (test) was loaded daily for 6 weeks, while the contra-lateral served as the unloaded one (control). A sinusoidally varying bending moment was applied at a frequency of 3 Hz and a force amplitude of 5 N, for 1800 cycli. Resonance frequency was measured at implant installation and from then on weekly using the RFA-device (Osstell®). Contrary to control implants, that showed a decrease in stability 1 week after installation, reaching a minimum at 3 weeks (,200 Hz), test implants showed a progressive increase in stability over time. After 6 weeks, the mean resonance frequency of test and control implants reached the same values. As confirmed by recent literature, early loading does not have to endanger the establishment of osseointegration of titanium implants. On the contrary, controlled loading is beneficial to maintain the implant stability during the early critical healing period as determined by RFA-measurements. Résumé La mise en charge précoce après l'insertion de l'implant acquière beaucoup d'intérêt en médecine dentaire. La stabilité primaire de l'implant, qui est par exemple définie par l'instrumentation de fréquence de résonnance RFA, a été isolée comme un annonciateur lorsque la mise en charge de l'implant était précoce ou immédiate. Le but de cette étude a été d'étudier l'effet d'une mise en charge précoce (sept jours) sur l'établissement de l'ostéïntégration à l'aide de RFA (Osstell®). Des implants titane percutanés ont été insérés dans les deux tibias de dix cobayes. Une semaine après le placement des implants, un implant test a été mis en charge tous les jours pendant six semaines tandis que le contralatéral servait de contrôle et n'était pas mis en charge. Un moment sinusoïdal a été appliquéà une fréquence de trois hertz et une amplitute d'une force de 5 N pour 1 800 cycles. La fréquence de résonnance a été mesurée lors de l'insertion de l'implant et ensuite hebdomadairement en utilisant le RFA. Contrairement aux implants contrôles, qui accusaient une diminution de la stabilité une semaine après leur insertion atteignant un minimum après trois semaines (,200 Hz), les implants tests ont montré une augmentation progressive de la stabilité avec le temps. Après six semaines, la fréquence de résonnance moyenne des implants tests et contrôles atteignaient les mêmes valeurs. Comme décrit dans la littérature récente, la mise en charge précoce ne met pas en danger l'établissement de l'ostéoïntégration des implants en titane. Au contraire, une mise en charge contrôlée est bénéfique au maintien de la stabilité implantaire durant la période de guérison critique précoce comme déterminée par les mesures RFA. Zusammenfassung Die Belastung kurz nach der Implantatplatzierung hat in der Zahnmedizin schnell an Interesse gewonnen. Die Primärstabilität der Implantate, bestimmt z.B. durch Messung der Resonanzfrequenz, hat sich als Voraussagewert herauskristallisiert, wenn eine Sofort-oder Frühbelastung der Implantate durchgeführt wird. Das Ziel dieser Studie war, den Einfluss der frühen (nach 7 Tagen) mechanischen Belastung auf die Ausbildung der Osseointegration mittels Resonanzfrequenzanalyse (RFA) zu untersuchen. In die beiden Tibias von 10 Meerschweinchen wurden perkutane Titanimplantate eingesetzt. Eine Woche nach der Implantation wurde ein Implantat (Test) während 6 Wochen täglich belastet, während das kontralaterale Implantat unbelastet blieb (Kontrolle). Es wurde ein Biegemoment mit sinusoidalen Schwankungen mit einer Frequenz von 3 Hz und einer Kraftamplitude von 5 N in 1800 Zyklen appliziert. Die Resonanzfrequenz wurde nach der Implantation und dann wöchentlich mit einem RFA-Gerät (Osstell®) gemessen. Im Gegensatz zu den Kontrollimplantaten, welche eine Woche nach dem Setzen eine Stabilitätsabnahme zeigten und das Minimum nach drei Wochen (,200 Hz) erreichten, konnte bei den Testimplantaten eine progressive Zunahme der Stabilität über die Zeit beobachtet werden. Nach sechs Wochen erreichten die mittleren Resonanzfrequenzen der Test-und Kontrollimplantate dieselben Werte. Die frühe Belastung gefährdet die Ausbildung einer Osseointegration bei Titanimplantaten nicht, was auch durch die neuere Literatur bestätig wird. Im Gegenteil, eine kontrollierte Belastung ist von Vorteil für den Erhalt der Implantatstabilität während der kritischen frühen Einheilphase. Dies konnte mittels RFA Messungen ermittelt werden. Resumen La carga temprana tras la colocación del implante ha ganado rápidamente interesen odontología. Se ha aislado como predictor, la estabilidad primaria del implante, definida por instrumentación de frecuencia de resonancia, cuando se aplica la carga temprana al implante. La intención del estudio fue investigar el efecto de carga mecánica temprana (tras 7 días) en el establecimiento de la osteointegración por medio del análisis de la frecuencia de resonancia (RFA). Se instalaron implantes de titanio percutaneos en ambas tibias de 10 conejos de indias. Una semana tras la instalación, un implante (prueba) se cargó diariamente durante 6 semanas, mientras que el contralateral sirvió como el implante sin carga (control). Se aplicó un momento de flexión variante sinusoidalmente a una frecuencia de 3 Hz y una amplitud de la fuerza de 5 N, durante 1899 ciclos. Se midió la frecuencia de resonancia al instalar el implante y a partir de ahí semanalmente usando el dispositivo RFA (Ostell®). Contrariamente a los implantes de control, que mostraron una disminución de la estabilidad una semana después de la instalación, alcanzando un mínimo a las tres semanas (,200 Hz), los implantes de prueba mostraron un incremento progresivo de la estabilidad a lo largo del tiempo. Tras seis semanas, la frecuencia de resonancia de los implantes de prueba y de control alcanzaron los mismos valores. Tal como se confirma por la literatura reciente, la carga temprana no debe hacer peligrar el establecimiento de la osteointegración de los implantes de titanio. Por lo contrario, la carga controlada es beneficiosa para mantener la estabilidad de los implantes durante el periodo crítico de la cicatrización determinado por las mediciones de RFA. [source] Microbiological and clinical outcomes and patient satisfaction for two treatment options in the edentulous lower jaw after 10 years of functionCLINICAL ORAL IMPLANTS RESEARCH, Issue 3 2005Marc Quirynen Abstract Background: Long-term data on microbiological and clinical outcome as well as on patient satisfaction after implant therapy in the edentulous mandible are limited. Especially comparisons between fixed full prostheses (FFPs) and overdentures (ODs), or between anchoring systems for the latter are scarce. Aim: This study aimed to evaluate both of these parameters at the 10-year follow-up in a group of fully edentulous patients rehabilitated via an OD or a FFP (the latter to allow inter-group comparison). Material and methods: A total of 37 fully edentulous patients (25 ODs, 12 FFPs, age at implant installation ranged from 36 to 85 years) participated in this study. All subjects received their implants (Brånemark System®, Nobel Biocare AB, Gothenburg, Sweden) 10 years previously. For the ODs different attachment systems (bar, magnets, ball) had been applied that allowed a further intra-group comparison. At the follow-up visit, 10 years after the abutment insertion, a series of periodontal parameters were recorded, long-cone radiographs were taken and subgingival plaque samples were collected for analysis using checkerboard DNA,DNA hybridization. The clinical and radiographic data were recorded at abutment connection and after 1 and 10 years. Results: After 10 years of loading, mean plaque and bleeding indices and changes in attachment or marginal bone level were not significantly different, neither between the OD and FFP group, nor within the OD group. The marginal bone loss between abutment connection and year 10 was 0.86 and 0.73 mm for OD and FFP groups, respectively. The subgingival microbiota at implant sites from all (sub)-groups was comparable, with low numbers of DNA counts (±10 × 105) but high detection frequencies of Actinobacillus actinomycetemcomitans (>90%), Porphyromonas gingivalis (>85%) and Tannerella forsythensis (30%). The composition of the subgingival microbiota was influenced by probing depth and bleeding tendency. Patient satisfaction was very high for both types of prosthetic rehabilitation. The FFP group scored only slightly better for chewing comfort and general satisfaction. Conclusion: These data indicate that from the clinical and microbiological standpoint, as well as patient satisfaction, both an OD and a FFP offer a favourable long-term outcome. Résumé Les données à long terme de la guérison clinique et microbiologique ainsi que la satisfaction du patient après un traitement par implants dans la mandibule édentée sont limitées. Essentiellement des comparaisons entre les prothèses fixées complètes et les prothèses fixées amovibles ou entre les systèmes d'ancrage pour ces derniers sont rares. Cette étude a eu pour but d'évaluer ces paramètres après dix ans dans un groupe de patients complètement édentés qui avaient été soignés par une prothèse amovible ou fixée (cette dernière pour permettre la comparaison intergroupes). Trente-sept patients édentés [25 prothèses amovibles (OD), douze prothèses fixées (FFP), l'âge au moment du placement des implants était de 36 à 85 ans] ont participéà cette étude. Tous les sujets avaient reçu des implants Brånemark® 10 ans auparavant. Pour les prothèses amovibles, différents types d'attache (balle, aimant) avaient été utilisés, ce qui permettaient une comparaison intragroupe supplémentaire. Lors de la visite du suivi, dix ans après l'insertion des implants, une série de paramètres parodontaux ont été enregistrés, des radiographies par long cône prises et des échantillons de plaque sous-gingivale prélevés pour l'analyse utilisant l'hybridisation ADN-ADN échiquier. Les données cliniques et radiographiques ont été enregistrées au moment de la connexion de l'implant et après une et dix années. Dix années après la mise en charge, les indices de plaque et de saignement et les variations dans l'attache ou les niveaux osseux marginaux n'étaient pas significativement différents ni entre les groupes OD et FFP ni à l'intérieur du groupe OD. La perte osseuse marginale entre les connexions des piliers et dix ans après étaient respectivement de 0,86 et 0,73 mm pour les groupes OD et FFP. La flore sous-gingivale au niveau des implants pour tous les groupes et sous-groupes étaient semblables avec de faibles comptages ADN (±10 × 105) mais des fréquences de détection importantes de A. actinomycetemcomitans (>90%), P. gingivalis (>85%) et T.forsythensis (30%). La composition de la flore sous-gingivale a été influencée par la profondeur de la poche et la tendance au saignement. La satisfaction du patient était très élevée pour les deux types de prothèses. Le groupe FFP n'était qu'un petit peu meilleur pour le confort à la mastication et la satisfaction générale. Ces données indiquent que d'un point de vue clinique et microbiologique autant que d'un point de vue de satisfaction du patient les prothèses amovibles et fixées sont favorables à long terme. Zusammenfassung Hintergrund: Die Langzeitresultate über den mikrobiologischen und klinischen Verlauf und über die Zufriedenheit der Patienten nach Implantatversorgung im zahnlosen Unterkiefer sind limitiert. Im Speziellen sind Vergleiche zwischen festsitzenden totalen Brücken und Hybridprothesen und den verschiedenen Befestigungssystemen für Hybridprothesen selten. Ziel: Das Ziel der Studie war, beide Parameter anlässlich der Nachuntersuchung nach 10 Jahren bei einer Gruppe von zahnlosen Patienten, welche mit einer Hybridprothese oder mit einer festsitzenden Brücke wiederhergestellt worden waren, auszuwerten (bei den Hybridprothesen sollten auch Vergleiche innerhalb der Gruppe durchgeführt werden). Material und Methoden: Insgesamt nahmen 37 zahnlose Patienten an der Studie teil (25 Hybridprothesen (OD), 12 festsitzende Prothesen (FFP), Alter zum Zeitpunkt der Implantation 36 bis 85 Jahre). Alle Subjekte hatte vor 10 Jahren ihre Implantate erhalten (Brånemark System®, Nobel Biocare, Schweden). Bei den Hybridprothesen waren verschiedene Befestigungssysteme verwendet worden (Steg, Magnet, Kugeln). Dies erlaubte Vergleiche innerhalb der Gruppe. Bei der Nachuntersuchung 10 Jahre nach Einsetzten der Prothetikteile wurden parodontale Parameter aufgenommen, Röntgenbilder mit der Langkonustechnik angefertigt und subgingivale Plaqueproben zur Analyse mittels Ceckerboard DNA,DNA Hybridisierung entnommen. Die klinischen und radiologischen Daten wurden beim Einsetzten der Prothetikteile und nach 1 und 10 Jahren aufgenommen. Resultate: Nach 10 Jahren Belastung bestanden weder zwischen der OD und FFP Gruppe, noch innerhalb der OD Gruppe statistisch signifikante Unterschiede im mittleren Plaque- und Blutungsindex und in der Attachment- und marginalen Knochenhöhe. Der Verlust an marginalem Knochen zwischen der Montage der Prothetikteile und nach 10 Jahren betrug 0.86 mm für die OD Gruppe und 0.73 mm für die FFP Gruppe. Die subgingivale Flora war bei allen Implantatstellen der (Sub-) Gruppen vergleichbar. Es bestand eine geringe Anzahl an DNA Zählungen (±10 × 105) aber eine hohe Entdeckungsfrequenz für A. actinomycetemcomitans (>90%), P. gingivalis (>85%) und T. forsythensis (30%). Die Zusammensetzung der subgingivalen Mirkoflora wurde durch die Sondierungstiefe und die Blutungstendenz beeinflusst. Die Zufriedenheit der Patienten war für beide Arten der prothetischen Wiederherstellung sehr hoch. Die FFP Gruppe erreichte nur geringfügig bessere Werte bezüglich Kaukomfort und genereller Zufriedenheit. Schlussfolgerung: Diese Daten zeigen, dass sowohl vom klinischen und mikrobiologischen Standpunkt aus als auch seitens der Patientenzufriedenheit die Hybridprothese und die festsitzende totale Brücke gute Langzeitresultate zeigen. Resumen Antecedentes: Los datos a largo plazo sobre los resultados microbiológicos y clínicos al igual que la satisfacción del paciente tras la terapia de implantes en la mandíbula edéntula son limitados. Son especialmente escasas las comparaciones entre prótesis fija completa y sobredentaduras, o entre sistemas de anclaje. Intención: Este estudio se intentó para evaluar ambos parámetros en el control de seguimiento de los 10 años en un grupo de pacientes totalmente edéntulos rehabilitados por medio de una sobredentadura o una prótesis completa fija (la última para permitir comparaciones intergrupo). Material y métodos: Un total de 37 pacientes totalmente edéntulos (25 sobredentaduras (OD), 12 prótesis completas fijas (FFP), la edad en el momento de la implantación varió entre 36 a 85 años) participaron en este estudio. Todos los sujetos recibieron sus implantes (Brånemark System®, Nobel Biocare, Suecia) 10 años antes. Para las sobredentaduras se aplicaron diferentes sistemas de anclaje (barras, imanes, bolas) lo que permitieron una ulterior comparación intragrupo. En la visita de seguimiento, 10 años tras la colocación de los pilares, se recogieron una serie de parámetros periodontales, se tomaron radiografías de cono largo y se recogieron muestras de la placa subgingival para análisis usando la cuadrícula de DNA-DNA hibridación. Los datos clínicos y radiográficos se recogieron al conectar los pilares y tras 1 y 10 años. Resultados: Tras 10 años de carga, los índices medios de placa y sangrado y los cambios en el nivel óseo marginal y de inserción no fueron significativos, ni entre los grupos OD y FFP, ni dentro del grupo OD. La pérdida de hueso marginal entre la conexión de los pilares y el año 10 fue de 0.86 y 0.73 mm para los grupos OD y FFP, respectivamente. La microflora subgingival en los lugares de implantes fue comparable entre todos los (sub)-grupos, con un bajo recuento de DNA (±10 × 105) pero una alta detección de A. actinomycetemcomitans (>90%), P. gingivalis (>85%) y T. forsythensis (30%). La composición de la microflora subgingival fue influida por la profundidad de sondaje y la tendencia al sangrado. La satisfacción de los pacientes fue muy alta para ambos grupos de rehabilitación protésica. El grupo FFP puntuó solo un poco mejor para la satisfacción masticatoria y satisfacción general. Conclusión: Estos datos indican que desde el punto de vista clínico y microbiológico al igual que la satisfacción del paciente, tanto la sobredentadura como la prótesis completa fija ofrecen unos resultados favorables a largo plazo. [source] Simultaneous or staged installation with guided bone augmentation of transmucosal titanium implantsCLINICAL ORAL IMPLANTS RESEARCH, Issue 6 2003A 3-year prospective cohort study Abstract: A prospective cohort study of 45 nonsmoking consecutively admitted patients was studied for the treatment outcomes following jaw bone augmentation in conjunction with installment of oral implants. Twenty-eight patients were treated for both bone augmentation and implant treatment simultaneously, while 17 patients were treated with a staged approach with the bone augmentation being performed 6,8 months prior to implant installation. Three months following this, prosthetic reconstructions were incorporated. One year thereafter, baseline data and 3 years after reconstruction, follow-up data were obtained. Moderately low mean scores for the bleeding on probing percentage were found at baseline (24%) and after 3 years of function (17%), while the corresponding values at the implant sites were 40.6% and 52.4%, respectively. However, the modified gingival index (mGI)=2 was found in only 4.8%, and 6.9% at the baseline and 3-year examinations. Peri-implant Probing depth (PPD) and level of attachment mean values did not vary between baseline and follow-up examinations. Only a small proportion of 1.8% yielded PPD=6.0 mm after 3 years of function. Radiographic bone level measurements showed that 18.2% of the implants lost 0.5 mm during the observation period. Seventy percent of the sites were considered completely stable. It was concluded that predictable treatment outcomes resulted for oral implant installation combined with or staged after jawbone augmentation. Only 6.5% of the sites had lost 1.5% crestal bone with the staged approach while 14% of the sites had lost 1.5 mm, when the implants were placed simultaneously. This suggests that the staged approach may have a lower risk for greater amounts of crestal bone loss as the simultaneous approach. In general, crestal bone loss encountered in the present study corresponded very well with that reported following placement of the same implant system into nonaugmented bone. Résumé Une étude prospective chez 45 non-fumeurs a été menée pour étudier le traitement suivant l'épaississement de l'os de la mâchoire en association avec le placement d'implants buccaux. Vingt-huit patients ont été traités pour un épaississement osseux et un traitement implantaire simultané tandis que 17 patients ont été traités par une approche de l'épaississement osseux effectuée six à huit mois avant le placement des implants. Trois mois après, les reconstructions prothétiques ont été placées. Une année plus tard les données de l'examen initial, et trois années après la reconstruction les données du suivi, ont été obtenues. Un pourcentage de BOP moyen modérément bas a été constaté lors de l'examen de départ (24%) et après trois années de mise en fonction (17%), tandis que les valeurs correspondantes au niveau des implants étaient respectivement de 41 et 52 %. Cependant, le mGI=2 était constaté seulement dans 5% et 7% lors des examens de départ et après trois ans. Les valeurs moyennes PPD et LA ne variaient pas entre l'examen de départ et les suivis. Seul une petite proportion de 2% avaient un PPD de 6,0 mm après trois années de mise en fonction. Les mesures du niveau osseux radiographique ont montré que 18% des implants perdaient 0,5 mm durant la période d'observation. Septante pour cent des sites étaient considérés complètement stables. Un traitement prévisible se produisait donc pour les implants osseux qu'ils aient été installés en une ou deux étapes. Seul 6,5% des sites avaient perdu 1,5% d'os crestal avec l'approche chirurgicale en une étape tandis que 14% des sites avaient perdu 1,5 mm lorsque les implants étaient placés en même temps que l'épaississement. L'approche en deux étapes pourrait s'accompagner d'un risque inférieur de perte osseuse importante au niveau crestal comparée à l'approche en une étape. En général, la perte osseuse crestale rencontrée dans l'étude présente correspondait très bien avec celle rapportée suivant le placement du même système d'implants dans l'os non-épaissi. Zusammenfassung In dieser prospektiven Kohortenstudie an 45 nichtrauchenden Patienten wurden die Behandlungsresultate nach Kieferkammaugmentation in Zusammenhang mit der Platzierung von oralen Implantaten untersucht. Bei 28 Patienten wurde die Knochenaugmentation und die Implantation in einem Eingriff durchgeführt, während bei 17 Patienten ein gestaffeltes Verfahren angewendet wurde, bei welchem die Knochenaugmentation 6,8 Monate vor der Implantatplatzierung stattfand. Drei Monate nach Implantation wurden die prothetischen Rekonstruktionen eingesetzt. Ein Jahr später wurden die Daten für die Ausgangsuntersuchung erhoben und drei Jahre nach Rekonstruktion wurden die Daten für die Nachuntersuchung aufgenommen. Bei der Ausgangsuntersuchung (24%) und nach drei Jahren in Funktion (17%) wurden relativ tiefe mittlere BOP % Werte gefunden, während die entsprechenden Werte bei den Implantatstellen 40.6% bzw. 52.4% betrugen. Jedoch wurde ein mGI=2 nur bei 4.8% anlässlich der Ausgangsuntersuchung und bei 6.9% bei der Nachuntersuchung gefunden. Die mittleren PPD und LA Werte variierten nicht zwischen der Ausgangs- und Nachuntersuchung. Nur ein kleiner Anteil von 1.8% zeigte eine PPD=6 mm nach drei Jahren in Funktion. Die Messung des radiologischen Knochenniveaus ergab, dass 18.2% der Implantate während der Beobachtungszeit einen Knochenverlust von 0.5 mm zeigten. 70% der Stellen wurde als komplett stabil angesehen. Es wurde die Schlussfolgerung gezogen, dass für die Eingliederung von oralen Implantaten zusammen mit Knochenaugmentation oder in einem gestaffelten Verfahren zu voraussagbaren Behandlungsresultaten führt. Nur 6.5% der Stellen im gestaffelten Vorgehen zeigten einen Knochenverlust von 1.5 mm während bei den gleichzeitig gesetzten Implantaten bei 14% der Stellen ein Knochenverlust von 1.5 mm auftrat. Dies lässt vermuten, dass das gestaffelte Vorgehen ein kleineres Risiko für grössere Knochenverluste haben könnte als das gleichzeitige Vorgehen. Generell betrachtet korrespondierte der in der vorliegenden Studie gesehene Knochenverlust sehr gut mit den Werten, die für das gleiche Implantatsystem nach dem Setzten in nichtaugmentierten Knochen berichtet werden. Resumen Se realizó un estudio prospectivo en serie sobre 45 pacientes no fumadores admitidos consecutivamente acerca de los resultados del tratamiento tras el aumento del hueso mandibular en conjunción con la instalación de implantes orales. Se trataron 28 pacientes para aumento del hueso y tratamiento de implantes simultáneamente mientras que 17 pacientes se trataron con un enfoque por fases con el aumento óseo realizado 6,8 meses antes de la instalación del implante. A los tres meses de esto, se incorporaron las reconstrucciones protésicas. Un año después, se obtuvieron datos de seguimiento, momento inicial y tres años tras la reconstrucción. Se encontró un % de BOP medio moderadamente bajo al inicio (24%) y tras tres años en función (17%), mientras que los valores correspondientes para los lugares de implante fueron 40.6% y 52.4%, respectivamente. De todos modos, el mGI=2 se encontró en solo 4.8%, y 6.9% al inicio y en el examen de los tres años. Los valores medios de PPD y LA no variaron entre el inicio y los exámenes de seguimiento. Solo una pequeña proporción del 1.8% produjo un PPD=6.0 mm tras tres años en función. Las mediciones del nivel radiográfico del hueso mostraron que el 18.2% de los implantes perdieron 0.5 mm durante el periodo de observación. El 70% de los lugares se consideraron completamente estables. Se concluyó que se obtuvieron unos resultados predecibles para instalación de implantes orales combinados con o en fases tras el aumento del hueso mandibular. Solo el 6.5% de los lugares perdió el 1.5% del hueso crestal con el enfoque por fases mientras que el 14% de los lugares perdieron 1.5 mm cuando los implantes se colocaron simultáneamente. Esto sugiere que el enfoque por fases puede tener un menor riesgo para mayores cantidades de perdida de hueso crestal que el enfoque simultaneo. En general, la perdida de hueso crestal encontrada en el presente estudio correspondió con muy buen con aquella informada tras la colocación del mismo sistema de implantes en hueso no aumentado. [source] Fate of monocortical bone blocks grafted in the human maxilla: a histological and histomorphometric studyCLINICAL ORAL IMPLANTS RESEARCH, Issue 6 2003Ilara R. Zerbo Abstract: Local bone defects in the anterior maxilla are commonly grafted with monocortical blocks of autologous bone in order to restore the defect site prior to the placement of dental implants. Increasing evidence suggests that osteocytes are involved in the control of bone remodelling and thus may be important for optimalisation of bone structure around implants, and thus for implant osseointegration. However, it is not well known whether osteocytes will survive when bone blocks are grafted into defects. We grafted 19 patients with monocortical bone blocks derived from the symphysis, to the defect site in the maxillary alveolar process. The bone grafts were left to heal for times varying from 2.5 to 7 months. During implant installation, bone biopsies were removed using a trephine burr, and processed for hard tissue histology. Bone histology and histomorphometry were then carried out in order to gain insight into the density, viability and remodelling of the graft. Clinically, all the bone grafts were successful, with no implant failures, and little resorption was seen. Histologically, bone volume expressed as percentage of tissue volume at the implant site varied from 27% to 57% with an overall average of 41%. Bone fields with empty osteocyte lacunae were observed and measured. The amount of this so-called nonvital bone (NVB) varied between 1% and 34% of the total tissue volume. The amount of NVB decreased significantly with the time of healing. The data suggest that the majority of the osteocytes of the monocortical bone do not survive grafting. The results indicate that the NVB is progressively remodelled into new vital bone 7 months after grafting. Résumé Les lésions osseuses locales dans le maxillaire antérieur sont souvent greffées avec des blocs monocorticaux d'os autogène afin de restaurer le site avant le placement d'implants. Il semble de plus en plus évident que les ostéocytes sont induits dans le contrôle du remodelage osseux et pourraient donc être importants pour optimiser la structure osseuse autour des implants et donc l'ostéoïntégration implantaire. Cependant le taux de survie des ostéocytes lorsque les blocs osseux sont greffés dans les lésions n'est pas suffisament connu. Dix-neuf patients ont été greffés avec des blocs osseux monocorticaux provenant de la symphyse dans le site de la lésion au niveau des alvéoles maxillaires. Les greffons osseux sont restés in situ durant des périodes de 2,5 à 7 mois. Pendant l'insertion des implants des biopsies osseuses ont été prélevées avec un trépan et analysées par histologie. L'histologie osseuse et l'histomorphométrie ont été effectuées afin d'analyser la densité, la viabilité et le remodelage osseux. Cliniquement tous les greffons osseux ont été effectués avec succès sans aucun échec implantaire et peu de résorption. Histologiquement, le volume osseux exprimé en tant que pourcentage du volume tissulaire au site implantaire variait de 27 à 57 % avec une moyenne totale de 41 %. Les champs osseux avec une lacune d'ostéocytes vides ont été observés et mesurés. La quantité d'os non-vivant variait de 1 à 34 % du volume tissulaire total. La quantité d'os non-vivant diminuait significativement avec le temps de guérison. Ces données suggèrent que la majorité des ostéocytes de l'os monocortical ne survivent pas au greffage. Les résultats indiquent que l'os non-vivant est progressivement remodelé en nouvel os vivant en sept mois après le greffage. Zusammenfassung Das Schicksal von monokortikalen Knochenblöcken, welche in die menschliche Maxilla transplantiert werden: eine histologische und histomorphometrische Studie Lokale Knochendefekte in der anterioren Maxilla werden normalerweise mit monokortikalen Blöcken aus autologem Knochen aufgebaut, um den Defekt vor der Eingliederung von dentalen Implantaten aufzufüllen. Aufgrund zunehmender Evidenz wird vermutet, dass Osteozyten an der Kontrolle der Knochenremodellierung beteiligt und daher wichtig für die Optimierung der Knochenstrukturen um Implantate und für die Osseointegration der Implantate sind. Es ist jedoch nicht ausreichend bekannt, ob Osteozyten überleben, wenn Knochenblöcke in Defekte transplantiert werden. Bei 19 Patienten wurden monokortikale Knochenblöcke von der Symphyse in den Defektbereich des Alveolarfortsatzes im Oberkiefer transplantiert. Die Knochentransplantate heilten in einer Zeit zwischen 2.5 und 7 Monaten ein. Während der Implantation wurden mit einer Hohlfräse Knochenbiopsien entnommen und für die Hartgewebshistologie aufgearbeitet. Der Knochen wurde histologisch und histomorphometrisch untersucht, um Einsicht in die Dichte, Vitalität und Remodellierung des Transplantats zu erlangen. Klinisch waren alle Knochentransplantate erfolgreich eingeheilt. Es konnten keine Implantatmisserfolge gesehen werden und es traten nur geringe Resorptionen auf. Histologisch variierte das Knochenvolumen, ausgedrückt als Prozentsatz Gewebevolumen an der Implantatstelle, von 27% bis 57% mit einem Durchschnitt von 41%. Knochenfelder mit leeren Osteozytenlakunen konnten beobachtet und ausgemessen werden. Die Menge dieses sogenannten nicht-vitalen Knochens variierte zwischen 1% und 34% des totalen Gewebevolumens. Die Menge des nicht-vitalen Knochens nahm signifikant mit der Länge der Einheilzeit ab. Die Daten lassen vermuten, dass die Mehrzahl der Osteozyten des monokortikalen Knochens die Transplantation nicht überleben. Die Resultate zeigen, dass der nicht-vitale Knochen innert 7 Monaten nach der Transplantation progressiv in neuen vitalen Knochen umgebaut wird. Resumen Los defectos óseos locales en el maxilar anterior se injertan comúnmente con bloques monocorticales de hueso autólogo en orden a restaurar el lugar del defecto antes de la colocación de implantes dentales. Una creciente evidencia sugiere que los osteocitos están involucrados en el control del remodelado óseo y de este modo ser importantes para la optimalización de la estructura ósea alrededor de los implantes y así para la osteointegración de los implantes. Sin embargo, no se conoce bien si los osteocitos sobrevivirán cuando los bloques óseos sean injertados en los defectos. Hemos injertado a 19 pacientes con bloques de hueso monocortical derivados de la sínfisis al lugar del defecto en el proceso alveolar maxilar. Los injertos óseos se dejaron cicatrizar por un periodo de tiempo que varió entre 2.5 a 7 meses. Durante la implantación se tomaron biopsias óseas usando una fresa de trépano y se procesaron para histología de tejidos duros. Se llevaron a cabo entonces histología ósea e histomorfometría en orden a hacerse una idea acerca de la densidad, viabilidad y remodelado del injerto. Clínicamente, todos los injertos óseos tuvieron éxito sin fracasos de implantes y se observó poca reabsorción ósea. Histológicamente, el volumen óseo expresado como porcentaje de volumen tisular en el lugar del implante varió del 27% al 57% con una media general del 41%. Se observaron y midieron campos óseos con lagunas óseas vacías. La cantidad de hueso no vital disminuyó significativamente durante el tiempo de cicatrización. [source] | ||||||||||