Infecciones del sitio quirúrgico en un hospital de enseñanza. Estudio observacional / Surgical site infections in a teaching hospital. Observacional study

Objetivo: determinar el número de pacientes que desarrollaron una infección postquirúrgica, posibles agentes etiológicos y complicaciones.Métodos : se realizó un estudio retrospectivo observacional que incluye a todos los supervivientes de las cirugías electivas y de emergencia de los servicios de Cirugía I, II y III del Hospital Universitario de Caracas durante el año 2019. Los datos fueron recopilados a través de la revisión de historias médicas. 48 historias cumplieron los criterios de inclusión, en estas se analizaron distintas variables como: días de hospitalización, síntomas, resultados de laboratorio, cultivos microbiológicos y tratamientos. A partir de estas se elaboraron tablas de frecuencia y análisis bivariado (Chi-cuadrado de Pearson) con el programa IBM SPSS Statistics 26.Resultados : la prevalencia de las infecciones postoperatorias fue de 4,69% CI 95% = (2,79-7,16%) en los servicios de Cirugía (I, II y III) del hospital durante el año 2019, la mayoría ocurrieron tras cirugías de emergencia (87,50%) tales como: apendicectomías (45,83%) y colecistectomías (10,41%). Solo al 22,91% de estos pacientes se les realizó cultivo microbiológico donde se encontró:E. coli (10,50%), Enterococcus sp. y Klebsiella pneumoniae (6,24%), Morganella morganii (2,1%) y Streptococcus pneumoniae (2,1%). Conclusión : las infecciones del sitio quirúrgico siguen siendo una de las principales causas de morbi-mortalidad y aumento de la estadía hospitalaria en los servicios de cirugía, son de diversa etiología bacteriana y están mayormente asociadas a cirugías abdominales, de emergencia(AU)

Objective: to determine the number of patients that developed a surgical site infection (SSI), possible etiologic agents and complications.Methods : an observational and retrospective study that includes every patient that underwent and survived a surgical procedure at the general surgery I, II and III services at the University Hospital of Caracas between January and December 2019. The study data were collected through the review of the medical records. 48 medical records that met the inclusion criteria and different variables were analyzed, including: days of hospitalization, symptoms, laboratory results, microbiological cultures and treatments. From those variables, frequency tables and bivariate analysis (Pearson's Chi-Square) were created with the IBM SPSS Statistics 26 program.Results : the SSI prevalence was 4,69% CI 95%= (2,79-7,16%) including the three surgery services (I, II and III) at the University Hospital of Caracas during 2019. Most of these occurred after emergency surgeries (87,50%) among which stand out: appendectomy (45,83%) and cholecystectomies (10,41%). Microbiological cultures were performed only in 22,91% of these patients and the following bacteria were isolated:E. coli (10,50%), Enterococcus sp. plus Klebsiella pneumoniae (6,24%), Morganella morganii (2,1%) and Streptococcus pneumoniae (2,1%). Conclusion : Surgical Site Infection (SSI) continues to be one of the main causes of morbimortality and increased hospital stay in surgical services in the hospital. These infections have a diverse bacterial etiology and are mostly associated with abdominal or emergency surgeries(AU)

Evaluation of the stability of sandblasted, large-grit, acid-etched implants with tapered straight body design

PURPOSE: Implant surface modification and implant design are the principle targets for achieving successful primary stability. The aim of this study was to measure implant stability quotient (ISQ) values of sandblasted, large-grit, acid-etched (SLA) implants with tapered straight body design during the healing period, and to determine the various factors affecting implant stability. MATERIALS AND METHODS: To measure implant stability, resonance frequency analysis (RFA) was performed in 26 patients (13 women and 13 men) with 44 SLA implants with tapered straight body design. Implant stability (ISQ values) was evaluated at baseline and healing abutment connection (12 weeks), and the correlations between RFA and insertion torque (IT), bone quality, and jawbone were determined. RESULTS: The mean ISQ value of the implants was 69.4 ± 10.2 at the time of implant placement (baseline) and 81.4 ± 6.9 at the time of healing abutment connection (P 0.05). CONCLUSION: ISQ values of SLA implants with tapered straight body design were high at baseline and healing abutment connection. It was concluded that SLA implants with tapered straight body design show improved primary and secondary stability, and that immediate or early loading may be applicable.

The rate and stability of mandibular block bone graft in recent 5 years / 대한악안면성형재건외과학회지

BACKGROUND: The purposes of the present study were to compare implant stabilities of mandibular block bone graft and bovine bone graft and to evaluate influencing factors for implant stability in mandibular block bone (MBB) graft. METHODS: This retrospective study investigated 1224 cases and 389 patients treated by one surgeon in the Department of Oral and Maxillofacial Surgery of Pusan National University Dental Hospital (Yangsan, Korea) between January 2010 and December 2014. Proportions that MBB graft cases constitute in all implant restoration cases and in all bone graft cases were measured. Implant stability quotient (ISQ) values were achieved by the same surgeon before loading. The average ISQ values of the experimental groups were compared. In addition, ISQ values of influencing factors, such as age, sex, implant size, and implant placement site, were compared within the MBB group using OsstellTM Mentor (Osstell®, Göteborg, Sweden). Paired t test and ANOVA were conducted for statistical analysis with a significance level of 0.05. RESULTS: Fifty-five percent of all implant restoration cases performed bone graft while MBB cases constituted 34% of all implant restoration cases and 61% of all bone graft cases. Comparing ISQ values according to bone graft materials, the MBB group manifested sufficient implant stability by presenting comparable ISQ value to that of the experimental group without bone graft. Among the reviewed factors, females, mandibular molar regions, and implants in larger diameter displayed greater implant stabilities. CONCLUSIONS: Satisfactory implant stability was accomplished upon administration of MBB graft. Within the limitation of this study, gender, implant site, and implant diameter were speculated to influence on implant stability in MBB graft.

Influencia de la orientación del sensor Osstell ISQ en los valores del coeficiente de estabilidad de los implantes / Influence of Osstell ISQ sensor orientation on implant stability quotient

Objetivo: en ciertas situaciones clínicas, puede ser necesario cambiar la orientación del sensor Osstell ISQ(TM) pero se desconocen los efectos de dicha modificación. El objetivo de la investigación fue verificar si los valores del coeficiente de estabilidad del implante (ISQ) difieren según cuál sea la orientación del sensor. Materiales y métodos: utilizando Osstell ISQ (Osstell Integration Diagnosis AB, Gotemburgo, Suecia), se midió el ISQ de 102 implantes de superficie Osteotite (Biomet 3i, Palm Beach Gardens, FL., Estados Unidos), con dos orientaciones diferentes del sensor: paralelo al SmartPeg (Integration Diagnostics AB, Gotemburg, Suecia) (vertical) y perpendicular a él (horizontal). Los valores de ISQ registrados para cada orientación se compararon mediante prueba de Wilcoxon para muestras relacionadas. Resultados: los valores de IsQ verticales difirieron de los ISQ horizontales en el 62,7 por ciento de los casos. Las diferencias entre los grupos resultaron estadísticamente significativas (P<0,05). La media de ISQ vertical (76,29) fue mayor que la de ISQ horizontal (74,78). Conclusión: si la situación clínica amerita un cambio de orientación del sensor, se deberá tener en cuenta que la medida de ISQ vertical observada podría diferir significativamente del valor que se habría obtenido realizando la medición de manera convencional.

El tamaño de partículas de injertos óseos en senos maxilares, tiene efectos diferenciales sobre la estabilidad? / Does the particle size of bone grafts in maxillary sinuses have differential effects on the stabilitiy of implants?

La elevación del piso del seno maxilar or medio de injertos óseos es un procedimiento predecible y frecuente para el tratamiento del reborde alveolar superior atrófico. El mateiççrial de injerto debe poseer propiedades mecánicas y biológicas que promuevan la osteoconducción y una buena estabilidad de los implantes colocados en dicho injerto. Objetivo: evaluar el efecto del tamaño de las partículas (pequeñas 0,25-1 mm o grandes 1-2 mm) de hidroxiapatita natural macroporosa de origen bovino, usadas en procedimientos de relleno de seno maxilar humano, sobre el coeficiente de estabilidad de los implantes (ISQ) que se coloquen en el injerto, obtenidos a través de análisis de frecuencia de resonancia. Material y método: se midió el coeficiente de estabilidad de 30 implantes colocados en 15 pacientes (8 varones y 7 mujeres), tratados con procedimientos de relleno de seno maxilar, usando como material de injerto hidroxiapatita natural macroporosa de origen bovino (Bio-Oss), de partículas grandes o de partículas pequeñas (11 y 7 respectivamente). Las mediciones se realizaron en el momento de la cirugía de colocación de los implantes a través de análisis de frecuencia de resonancia. El período de cicatrización de las elevaciones de seno maxilar fue de 8 a 9 meses. Los datos fueron analizados con estadística no paramétrica. Resultados: no se detectaron diferencias significativas en los varones de ISQ de los implantes colocados en senos rellenados con partículas pequeñas og randes (P<0,05). Los valores de desvío estándar de RFA fueron numéricamente mayores en partículas grandes (+- 13,46 ISQ) que en las pequeñas (+- 5,23 ISQ). Conclusión: dentro de las limitaciones de este estudio realizado en senos maxilares humanos, se concluye que el diferente tamaño de las partículas de hidroxiapatita natural macroporosa de origen bovino, no tiene un efecto diferencial en los valores de ISQ de los implantes dentales colocados en los senos tratados...

The influence of implant diameter, length and design changes on implant stability quotient (ISQ) value in artificial bone / 대한치과보철학회지

PURPOSE: The purpose of this study is to ascertain the stability of the implant by comparing the effects of the change of implant diameter, length and design on implant stability quotient. MATERIALS AND METHODS: To remove the variable due to the difference of bone quality, the uniform density (0.48 g/cm3) Polyuretane foam blocks (Sawbones(R), Pacific Research Laboratories Inc, Vashon, Washington) were used. Implants (Implantium(R), Dentium, Seoul, Korea) were placed with varying diameters (phi3.8, phi4.3 and phi4.8) and length (8 mm, 10 mm and 12 mm), to assess the effect on implant stability index (ISQ). Also the influence of the design of the submerged and the non-submerged (SimplelineII(R), Dentium, Seoul, Korea) on ISQ was evaluated. To exclude the influence of insertion torque, a total of 60 implants (n = 10) were placed with same torque to 35 N. Using Osstell(TM) mentor (Integration Diagnostic AB, Sweden) ISQ values were recorded after measuring the resonant frequency, one-way ANOVA and Tukey HSD test results were analyzed. (alpha=0.05). RESULTS: 1. The change of the diameter of the implant did not affect the ISQ (P>.05), but the increase of implant length increased the ISQ(P<.001). 2. The change in implant design were correlated with the ISQ, and the ISQ of submerged design was significantly higher than that of the non-submerged design(P<.05). CONCLUSION: In order to increase implant stability, the longer implant is better to be selected, and on the same length of implant, submerged design is thought to be able to get a higher ISQ than the non-submerged.

Effect of bone quality and implant surgical technique on implant stability quotient (ISQ) value

PURPOSE: This study investigated the influence of bone quality and surgical technique on the implant stability quotient (ISQ) value. In addition, the influence of interfacial bone quality, directly surrounding the implant fixture, on the resonance frequency of the structure was also evaluated by the finite element analysis. MATERIALS AND METHODS: Two different types of bone (type 1 and type 2) were extracted and trimmed from pig rib bone. In each type of bone, the same implants were installed in three different ways: (1) Compaction, (2) Self-tapping, and (3) Tapping. The ISQ value was measured and analyzed to evaluate the influence of bone quality and surgical technique on the implant primary stability. For finite element analysis, a three dimensional implant fixture-bone structure was designed and the fundamental resonance frequency of the structure was measured with three different density of interfacial bone surrounding the implant fixture. RESULTS: In each group, the ISQ values were higher in type 1 bone than those in type 2 bone. Among three different insertion methods, the Tapping group showed the lowest ISQ value in both type 1 and type 2 bones. In both bone types, the Compaction groups showed slightly higher mean ISQ values than the Self-tapping groups, but the differences were not statistically significant. Increased interfacial bone density raised the resonance frequency value in the finite element analysis. CONCLUSION: Both bone quality and surgical technique have influence on the implant primary stability, and resonance frequency has a positive relation with the density of implant fixture-surrounding bone.

The relationship between initial implant stability quotient values and bone-to-implant contact ratio in the rabbit tibia

PURPOSE: Implant stability quotient (ISQ) values have been supposed to predict implant stability. However, the relationship between ISQ values and bone-to-implant contact ratio (BIC%) which is one of the predictors of implant stability is still unclear. The aim of the present study was to evaluate initial ISQ values in relation to BIC% using rabbit model. MATERIALS AND METHODS: Four New Zealand white rabbits received a total of 16 implants in their tibia. Immediately after implant placement ISQ values were assessed. The measurements were repeated at the time of sacrifice of the rabbits after 4 weeks. Peri-implant bone regeneration was assessed histomorphometrically by measuring BIC% and bone volume to total volume values (bone volume %). The relationships between ISQ values and the histomorphometric output were assessed, and then, the osseointegration prediction model via the initial ISQ values was processed. RESULTS: Initial ISQ values showed significant correlation with the BIC%. The bone volume % did not show any significant association with the ISQ values. CONCLUSION: In the limitation of this study, resonance frequency analysis is a useful clinical method to predict the BIC% values and examine the implant stability.

The study of bone density assessment on dental implant sites

INTRODUCTION: Bone density is one of the important factors for the long term success of endosseous implants. The bone density varies from site to site and from patient to patient. A preoperative evaluation of the bone density is quite useful to oral surgeons for planning dental implantation. More accurate information on the bone density will help surgeons identify suitable implant sites, thereby increase the success rate of dental implantation. This study examined the correlation between the bone density measured preoperatively by computed tomography (CT) and the implant primary stability measured by resonance frequency analysis. Furthermore, the effects of the implant sites, gender, age and generalized systemic disorder patients on the bone density and primary implant stability were examined. MATERIALS AND METHODS: One hundred and fourteen patients were selected. None of the patients had undergone a tooth extraction or bone graft history in the previous year. Preoperatively, the patients underwent CT scanning to evaluate the Hounsfield unit (HU), and resonance frequency analysis (RFA) was used to evaluate the implant primary stability at the time of implant installation. All implants were 4.0 mm diameter and 11.5 mm length US II. All patients were recorded and the HU and implant stability quotient (ISQ) value were evaluated according to the sites, gender and age. RESULTS: The highest HU values were found in the mandibular anterior site (827.6+/-151.4), followed by the mandibular molar site (797+/-135.1), mandibular premolar site (753.8+/-171.2), maxillary anterior site (726.3+/-154.4), maxillary premolar site (656.7+/-173.8) and maxillary molar site (621.5+/-164.9). The ISQ value was the highest in the mandibular premolar site (81.5+/-2.4) followed by the mandibular molar site (80.0+/-5.7), maxillary anterior site (77.4+/-4.1), mandibular anterior site (76.4+/-11.9), maxillary premolar site (74.2+/-14.3) and maxillary molar site (73.7+/-7.4). The mean HU and ISQ value were similar in females and males. (HU: P=0.331, ISQ: P=0.595) No significant difference was also found in the age group respectively. However, the correlation coefficients between the variables showed a closed correlation between the HU and ISQ value. CONCLUSION: These results showed close correlation between the bone density (HU) and primary stability value (ISQ) at the time of implant installation (Correlation coefficients=0.497, P<0.01). These results strengthen the hypothesis that it might be possible to predict and quantify the initial implant stability and bone density from a presurgical CT diagnosis. These results strengthen the hypothesis that it might be possible to predict and quantify the initial implant stability and bone density from a presurgical CT diagnosis.

Immediate implant placement after extraction of retained deciduous teeth and impacted canines : Report of a case

A comparative study on the accuracy of the devices for measuring the implant stability

STATEMENT OF PROBLEM: How the ISQ values measured by Osstell(TM) and Osstell(TM) Mentor are related, and whether the ISQ values acquired from the two machines changes in accordance with changes in implant stability are not yet fully understood. PURPOSE: The aim of this study was to find out correlation between the ISQ values acquired from Osstell(TM) and Osstell(TM) Mentor, and to evaluate the clinical effectiveness and accuracy of two devices. MATERIAL AND METHODS: Sixty two implants were inserted into 47 patients, and their ISQ values were measured using Osstell(TM) and Osstell(TM) Mentor. In the first stage surgery, the ISQ values of forty four implants inserted into thirty five patients were measured. In the second stage surgery, the values of fifty implants inserted into thirty seven patients were measured. The values were analyzed to determine the difference between the mean ISQ values of Osstell(TM) and Osstell(TM) Mentor. In addition, the correlation between implants used in the first and second stage of surgery with regard to their types and areas of insertion were analyzed. The difference between the ISQ values of 32 implants in each patient during the first and second stage was analyzed. The statistical assessment was carried out using SPSS V. 12.0 for Win. (SPSS Inc., Chicago, USA). The Pearson correlation coefficient was used to examine the correlation between Osstell(TM) and Osstell(TM) Mentor in the first and second stages of surgery, whereas the difference between their ISQ values was evaluated using a paired t-test. RESULTS: In the first stage, the mean ISQ value for Osstell(TM) and Osstell(TM) Mentor was 70.84 and 75.09, respectively, showing a significant difference (P < .01). In the second stage, the mean ISQ value of Osstell(TM) and Osstell(TM) Mentor was 71.76 and 75.94, respectively, also showing a significant difference (P < .01). The difference between the ISQ values in patients in the first and the second stages was significant with both instruments. CONCLUSION: The significant difference in the values obtained using the Osstell(TM) and Osstell(TM) Mentor between the first and second stages of implant surgery indicates that these values can be a convenient and precise way for evaluating the implant stability in clinical practice.

The effect of various thread designs on the initial stability of taper implants

STATEMENT OF PROBLEM: Primary stability at the time of implant placement is related to the level of primary bone contact. The level of bone contact with implant is affected by thread design, surgical procedure and bone quality, etc. PURPOSE: The aim of this study was to compare the initial stability of the various taper implants according to the thread designs, half of which were engaged to inferior cortical wall of type IV bone (Group 1) and the rest of which were not engaged to inferior cortical wall (Group 2) by measuring the implant stability quotient (ISQ) and the removal torque value (RTV). MATERIAL AND METHODS: In this study, 6 different implant fixtures with 10 mm length were installed. In order to simulate the sinus inferior wall of type IV bone, one side cortical bone of swine rib was removed. 6 different implants were installed in the same bone block following manufacturer's recommended procedures. Total 10 bone blocks were made for each group. The height of Group 1 bone block was 10 mm for engagement and that of group 2 was 13 mm. The initial stability was measured with ISQ value using Osstell mentor(R) and with removal torque using MGT50 torque gauge. RESULTS: In this study, we found the following results. 1. In Group 1 with fixtures engaged to the inferior cortical wall, there was no significant difference in RTV and ISQ value among the 6 types of implants. 2. In Group 2 with fixtures not engaged to the inferior cortical wall, there was significant difference in RTV and ISQ value among the 6 types of implants (P < .05). 3. There was significant difference in RTV and ISQ value according to whether fixtures were engaged to the inferior cortical wall or not (P < .05). 4. Under-drilling made RTV and ISQ value increase significantly in the NT implants which had lower RTV and ISQ value in Group 2 (P < .05). CONCLUSIONS: Without being engaged to the inferior cortical wall fixtures had initial stability affected by implant types. Also in poor quality bone, under-drilling improved initial stability.

Comparion of stability in titanium implants with different surface topographies in dogs

STATEMENT OF PROBLEM: A few of studies which compared and continuously measured the stability of various surface treated implants in the same individual had been performed. PURPOSE: We aim to find the clinical significance of surface treatments by observing the differences in the stabilization stages of implant stability. MATERIAL AND METHODS: Eight different surface topographies of dental implants were especially designed for the present study. Machined surface implants were used as a control group. 4 nano-treated surface implants (20 nm TiO2 coating surface, heat-treated 80 nm TiO2 coating surface, CaP coating surface, heat treated CaP coating surface) and 3 micro-treated surface implants [resorbable blast media (RBM) surface, sandblast and acid-etched (SAE) surface, anodized RBM surface] were used as experiment groups. All 24 implants were placed in 3 adult dogs. Periotest(R) & ISQ values measured for 8 weeks and all animals were sacrificed at 8 weeks after surgery. Then the histological analyses were done. RESULTS: In PTV, all implants were stabilized except 1 failed implants. In ISQ values, The lowest stability was observed at different times for each individual. The ISQ values were showed increased tendency after 5 weeks in every groups. After 4 to 5 weeks, the values were stabilized. There was no statistical correlation between the ISQ values and PTV. In the histological findings, the bone formation was observed to be adequate in general and no differences among the 8 surface treated implants. CONCLUSIONS: In this study, the difference in the stability of the implants was determined not by the differences in the surface treatment but by the individual specificity.

A compare research of machined implant and RBM surface implant / 대한치주과학회지

PURPOSE: To evaluate RBM surface implant which has its good character like that good initial stability, early bone formation. MATERIAL AND METHODS: In this study fixures have divided in 2 group: Machined(Group I), RBM(Group II). Total 10 fixtures were implanted on rabbit which sacrificed on week 2 and week 4 for the histological specimens. By these specimens polarized microscopic view, micro CT view, ISQ value were measured, compared and analysed by each group to figure out the evidence that clinical use of RBM implant. RESULT: ISQ value had no significance differences between 2 groups, However in each group 4, 8 weeks had higher ISQ value than 2 weeks. In polarized microscope, calcification level was following : Group II, Group I. In micro CT, formation of cancellous bone level was following : Group II, Group I. CONCLUSION: RBM implant was the most excellent on the early bone formation and good initial stability.

Stability changes of immediately loaded and delayed loaded implants in edentulous mandible / 대한치과보철학회지

STATEMENT OF PROBLEM: It was reported high success rate of implant-supported fixed prostheses using with 5.6 implants on anterior mandible. Recently, immediate loading protocol was focused to overcome disadvantages of classic 2-stage delayed loading protocol. PURPOSE: This clinical study was to evaluate stability changes with time of immediately loaded and delayed loaded implants in edentulous mandible and to compare stability changes with time according to implantation sites. MATERIALS AND METHODS: Five or six implants were placed on anterior mandible depending on the arch shape. The immediately loading group was consisted of 8 patients received their prostheses within 24.48 hours after implantation. The delayed loading group was consisted of 8 patients received their definitive prostheses following classical prosthetic procedures after a healing period of 3 months. All patients were recalled every 6 months for check-up. The evaluations of radiographic examination, ISQ value measurement and recording of complication were done. To evaluate marginal bone level, intraoral periapical radiographs were taken with long cone paralleling technique. At every evaluation recall, all prostheses were removed and ISQ values were measured with Osstell(TM) on individual implants. RESULTS: 1. None of implants was failed. All implants showed stable marginal bone levels and ISQ values. 2. Marginal bone level changes with time showed statistically significant difference between immediately loading group and delayed loading group (P<0.001). 3. ISQ value changes with time did not show statistically significant difference between immediately loading group and delayed loading group (P=0.079). ISQ value decreased with time in both groups, however, all implants showed stable ISQ value at 30 months-recall evaluation. 4. Marginal bone level changes with time did not show statistically significant differences among implantation sites (P=0.604). 5. ISQ value changes with time showed statistically significant differences among implantation sites (P=0.047). ISQ values of most posterior implants decreased with time comparing to other implants. CONCLUSION: Although the marginal bone level of the terminal abutment didn't different with the other implants, ISQ value of the terminal abutment was lower than that of the other implants. Therefore, further clinical evaluation would be needed in this point of view.

The effect of autoclave sterilization and reuse of Smartpeg(TM) on the implant stability quotient (ISQ) measurement / 대한치과보철학회지

STATEMENT OF PROBLEM: Resonance frequency analysis is evaluated as the non-invasive and objective method for the evaluation of implant stability and has been increasingly used. It is necessary to evaluate the factors affect the ISQ measurement stability. PURPOSE: This study was performed to evaluate the effect of the autoclave sterilization and reuse of Smartpeg(TM) on ISQ measurement. MATERIAL AND METHODs: SmartPeg(TM) (Integration Diagnostics Ltd., Goteborg, Sweden) of autoclave group (A) was autoclave sterilized 9 times and Smartpeg(TM) of reuse group (R) was reused 9 times. Ten SmartPeg(TM)s were allocated to each group and after each autoclave sterilization and reuse, implant stability quotient (ISQ) values were measured 3 times from the two directions a and b at a right angle. Osstell(TM) mentor (Integration Diagnostics Ltd., Goteborg, Sweden) was used and type 1 (article no. 100353) Smartpeg(TM) was selected according to SmartpegTM reference list. Osstem Implant US II fixture (Osstem Co., Seoul, Korea) in 4.0 mm x 11.5 mm was embedded in the self-curing acrylic resin (Orthojet(R), Lang Dental, U.S.A.). Data was statistically analyzed by one-way ANOVA (alpha= .05) and scheffe test was done where a significant difference exist. Correlation test was also done between ISQ value and the number of autoclave sterilization or reuse. RESULTS: 1. In autoclave group, the means and sd. of ISQ value before autoclave sterilization were 84.97 +/-0.41, 84.93+/-0.74 at direction a and b. There was significant differences between autoclave groups at direction a and b (P=.000). 2. In reuse group, the means and sd. of ISQ value before reuse were 85.40+/-0.62, 85.50+/-0.57 at direction a and b. There was no significant difference between reuse groups at direction a and b (P>.05). 3. There was a weak positive correlation between the number of reuse and ISQ value at direction a and b (gamma=.207 and .246, P<.01). CONCLUSION: Within the limitations of this study, the following CONCLUSIONs were drawn. Till ninth reuse of Smartpeg(TM), the ISQ measurement stability did not be affected. After twice autoclave sterilization of Smartpeg(TM), the ISQ measurement stability was affected.

Maxillary sinus augmentation with bovine bone mineral (bio-oss.) and the maxillary tuberosity

The aim of this study was to evaluate implant stability placed in the maxillary sinus which was augmented with bovine bone mineral (Bio-Oss.) mixed with autogenous bone from the maxillary tuberosity. Maxillary sinus floor augmentation with the mixture of bovine bone mineral and autogenous maxillary tuberosity bone was performed in 30 maxillary sinuses, and 68 implants were placed at the time of sinus graft. After 6 months of implant placement abutments were connected and implant stability quotient (ISQ) was measured by radio frequency analysis (RFA). In addition, bone level changes was evaluated by taking periapical radiograph. During surgical procedures, no complication was observed, and all patients healed uneventfully. At 6 months the implant showed stable ISQ values. The marginal bone level changes around the fixtures was stably maintained through out the follow up period. This study confirmed that maxillary sinus floor augmentation with mixture of bovine bone mineral and maxillary tuberosity bone could be reliable for bone regeneration in subantral space.

Influence of implant fixture design on implant primary stability / 대한치과보철학회지

STATEMENT OF PROBLEM: Current tendencies of the implant macrodesign are tapered shapes for improved primary stability, but there are lack of studies regarding the relationship between the implant macrodesign and primary stability. PURPOSE: The purpose is to investigate the effect of implant macrodesign on the implant primary stability by way of resonance frequency analysis in the bovine rib bones with different kinds of quality. MATERIAL AND METHOD: Fifty implants of 6 different kinds from two Korean implant systems were used for the test. Bovine rib bones were cut into one hundred pieces with the length of 5 cm. Among them forty pieces of rib bones with similar qualities were again selected. For the experimental group 1, the thickness of cortical part was measured and 20 pieces of rib bones with the mean thickness of 1.0mm were selected for implant placement. For the experimental group 2, the cortical parts of the remaining 20 pieces of rib bones were totally removed and then implants were placed on the pure cancellous bone according to the surgical manual. After placement of all implants, the implant stability quotient(ISQ) was measured by three times, and its statistical analysis was done. RESULTS: There are statistically significant differences in ISQ values among 4 different kinds of Avana system implants in the experimental group 2. For the experimental group 1, Avana system implants showed significantly different ISQ values, but when differences in the thickness of cortical parts were statistically considered, did not show any significant differences in ISQ values. Among Oneplant system implants, there are no significant differences in ISQ values for the experimental group 2 as well as for the experimental group 1. CONCLUSION: Within the limits of this study, bone quality and implant design have some influences on the primary stability of implants. Especially in the bone of poor quality, tapered shape of implants are more favorable for the primary stability of implants.

The influencing factors of periotest. value and implant stability quotient / 대한치과보철학회지

STATEMENT OF PROBLEM: Periotest. and OsstellTM were known as the most objective and quantitative mobility tests available for evaluating stability of implant in vivo. Although a correlation between PTV widely used and ISQ recently introduced exist, a PTV was corresponded to various ISQ. A correct evaluation of implant stability could be obtained only after one has a thorough understanding of the limitations of devices and factors that affect measurements. PURPOSE: The purpose of this study was to investigate the causes of variables in the values obtained with these two tests. MATERIAL AND METHOD: A total of 333 implants: 134 Bra.nemark, 5 Silhouette and 194 ITI implants were investigated. Result: 1. There was a correlation between PTV and ISQ (Spearman correlation =0.39, p<0.0001) 2. The factors that affected ISQ were diameter of implant fixture, location of implant and implant system (submerged type vs non-submerged type). 3. The factors that affected PTV were diameter of implant fixture, location of implant, and elapsed time after implant placement. 4. There was no significant difference between different surface treatments of RBM, smooth surface and ti-unite on PTV and ISQ. 5. In radiographic finding, no saucerization or bone resorption has been detected in implants with ISQ values that were above the average level of each PTV. These higher values had higher bone densities around the implant fixture. Saucerization was observed in the most impants with ISQ values that were below the average level of each PTV. CONCLUSION: There was a correlation between ISQ and PTV. However, each measuring methods had factors influencing the measured values. PTV were less sensitive to marginal bone resorption and influenced with the striking point on an implant to the level of bone. With ISQ, the height of implant from bone level to transducer should be considered.

The influencing factors of periotest. value and implant stability quotient / 대한치과보철학회지

STATEMENT OF PROBLEM: Periotest. and OsstellTM were known as the most objective and quantitative mobility tests available for evaluating stability of implant in vivo. Although a correlation between PTV widely used and ISQ recently introduced exist, a PTV was corresponded to various ISQ. A correct evaluation of implant stability could be obtained only after one has a thorough understanding of the limitations of devices and factors that affect measurements. PURPOSE: The purpose of this study was to investigate the causes of variables in the values obtained with these two tests. MATERIAL AND METHOD: A total of 333 implants: 134 Bra.nemark, 5 Silhouette and 194 ITI implants were investigated. Result: 1. There was a correlation between PTV and ISQ (Spearman correlation =0.39, p<0.0001) 2. The factors that affected ISQ were diameter of implant fixture, location of implant and implant system (submerged type vs non-submerged type). 3. The factors that affected PTV were diameter of implant fixture, location of implant, and elapsed time after implant placement. 4. There was no significant difference between different surface treatments of RBM, smooth surface and ti-unite on PTV and ISQ. 5. In radiographic finding, no saucerization or bone resorption has been detected in implants with ISQ values that were above the average level of each PTV. These higher values had higher bone densities around the implant fixture. Saucerization was observed in the most impants with ISQ values that were below the average level of each PTV. CONCLUSION: There was a correlation between ISQ and PTV. However, each measuring methods had factors influencing the measured values. PTV were less sensitive to marginal bone resorption and influenced with the striking point on an implant to the level of bone. With ISQ, the height of implant from bone level to transducer should be considered.