• The Journal of Advanced Prosthodontics
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• v.5 no.4
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• pp.494-501
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• 2013

PURPOSE. The purpose of this study was to provide an actual guideline in determining the shape, diameter, and position of the implant in immediate implantation by the measurement of the thickness of facial and palatal plate, the thickness of cortical bone on the facial and palatal plate, the diameter of the root, and the distance between the roots in the cadavers. MATERIALS AND METHODS. The horizontal sections of 20 maxillae were measured and analyzed to obtain the average values. Resin blocks were produced and cut serially at 1 mm intervals from the cervical line to the root apex. Images of each section were obtained and the following measurements were performed: The thickness of the facial and palatal residual bone at each root surface, the thickness of the facial and palatal cortical bone at the interdental region, the diameter of all roots of each section on the faciopalatal and mesiodistal diameter, and the interroot distance. Three specimens with measurements close to the average values were chosen and 3-dimensional images were reconstructed. RESULTS. The thickness of the facial and palatal cortical bone at the interdental region in the maxilla, the buccal cortical bone was thicker in the posterior region compared to the anterior region. The interroot distance of the alveolar bone thickness between the roots increased from anterior to posterior region and from coronal to apical in the maxilla. CONCLUSION. In this study, the limited results of the morphometric analysis of the alveolar ridge using the sections of maxilla in the cadavers may offer the useful information when planning and selecting optimal implant for immediate implantation in the maxilla.

• The Journal of the Korean dental association
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• v.48 no.2
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• pp.119-126
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• 2010

Introduction. In this study, we applied the immediate loading to implant using temporary prosthesis, and compared the treatment results by each placement site, amongst pre-loading period. The study was intended to search for occurrence of complications and the amount of marginal bone resorption. Materials and Methods. We retrospectively reviewed the medical records of 99 cases of implants from 29 patients who were treated at Seoul National University Bundang Hospital from September 2003 to September 2008. We grouped all the cases by placement arches and pre-loading periods, and subdivided each group by placement site(anterior/posterior), type of prosthesis(full-mouth cross splinting/Partial multiple splinting, Single). Results. In the cases of anterior maxilla, the average amounts of marginal bone resorption showed $1.71{\pm}0.71mm$ in group 1, and $1.44{\pm}0.69mm$ in group 2, which means they revealed no statistically significant difference between group 1 and group 2(p=0.646). In the cases of posterior maxilla, the average amounts of marginal bone resorption showed $1.25{\pm}0.72mm$ in group 1, and $1.14{\pm}1.15mm$ in group 2, which means they were not statistically significant. In the cases of anterior mandible, there was no cases classified as group 4, but the average amounts of marginal bone resorption in group 3 showed $1.38{\pm}0.79mm$. In the cases of posterior mandible, Group 3 showed $1.39{\pm}0.64mm$, and group 4 showed $1.84{\pm}1.19mm$ as amounts of marginal bone resorption, which means they revealed no statistically significant difference between group 3 and group 4(P=0.210). The survival rate of group1 was 97.14%, 92.1% of group3, and 100% of group 2 and group4. According to each type of prosthesis, each average amount of marginal bone resorption revealed no statistically significant difference in maxi11a(p=0.575) in mandible(p=0.206). Conclusion. It is concluded that the marginal bone resorption and the rate of complications might not be affected by placement sites and pre-loading periods. The marginal bone resorption and the rate of complications might vary as different bone quality of placement site and implant system, diameter, length, etc. It is suggested that the proper placement of immediate loading implants decreases the whole treatment period and any inconvenience occurred to patients.

• Archives of Craniofacial Surgery
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• v.17 no.1
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• pp.20-24
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• 2016

Background: Midface concavity is a relatively common facial feature in East Asian populations. Paranasal augmentation is becoming an increasingly popular procedure for patients with mild concavity and normal occlusion. In this study, we evaluate clinical outcomes following a series of paranasal augmentation. Methods: A retrospective review was performed for patients with Class I occlusion who had undergone bilateral paranasal augmentation using custom-made silicone implants, between October 2005 and September 2013. Patient charts were reviewed for demographic information, concomitant operations, and postoperative complications. Preoperative and postoperative (1-month) photographs were used to evaluate operative outcome. Results: The review identified a total of 93 patients meeting study criteria. Overall, aesthetic outcomes were satisfactory. Five-millimeter thick silicone implant was used in 81 cases, and the mean augmentation was 4.26 mm for this thickness. Among the 93 patients, 2 patients required immediate implant removal due to discomfort. An additional 3 patients experienced implant migration without any extrusion. Nine patients complained of transient paresthesia, which had resolved by 2 weeks. There were no cases of hematoma or infection. All patients reported improvement in their lateral profile and were pleased at follow-up. Complications that arose postoperatively included 9 cases of numbness in the upper lip and 3 cases of implant migration. All cases yielded satisfactory results without persisting complications. Sensations were fully restored postoperatively after 1 to 2 weeks. Conclusion: Paranasal augmentation with custom-made silicone implants is a simple, safe, and inexpensive method that can readily improve the lateral profile of a patient with normal occlusion. When combined with other aesthetic procedures, paranasal augmentation can synergistically improve outcome and lead to greater patient satisfaction.

• Journal of Dental Rehabilitation and Applied Science
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• v.19 no.4
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• pp.291-296
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• 2003

The use of resonance frequency analysis (RFA) provides a possibility to clinically measure implant stability and osseointegration. The implant stability quotient (ISQ) value of RFA is well known that influenced by effective abutment length and stiffness of the implant in the surrounding tissues. Among these factors stiffness is not accurately defined histologically yet. And the purpose of this study was to find the histolgical relationship of RFA. 17 implants in 3 beagle dogs were used for this study. Among these implants 10 were survived for 7 months, 4 were survived for 3 months and 3 were immediate status after placement. Resonance frequency analyses were conducted and the dogs were sacrificed. Percentage of the bone to implant contact (BIC) in the interface, percentage of the mineralized bone (bone area) within the threads of the implant, and marginal bone level were measured under light microscopy. The correlation between resonance frequency and histomorphometric measurements were analysed and following results were obtained. 1. There was statistically significant correlation between ISQ value and BIC on healed implants. But ISQ value and BIC of all implants were not significantly correlated. (P<0.01) 2. Significant correlation between ISQ value and bone area was not found in this study. 3. There was statistically significant correlation between ISQ value and marginal bone level on all implants as well as on healed implants. (P<0.01).

• Archives of Plastic Surgery
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• v.40 no.4
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• pp.374-379
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• 2013

Background To date, various types of acellular dermal matrix (ADM) have been developed for clinical use. AlloDerm is the most familiar type of ADM to most surgeons in breast reconstruction. It is prepared by freeze-drying. CG CryoDerm is the first form of ADM that requires no drying process. Therefore, theoretically, it has a higher degree of preservation of the dermal structures than AlloDerm. We conducted this study to compare the clinical course and postoperative outcomes of patients who underwent direct-to-implant breast reconstructions using AlloDerm and those who did using CG CryoDerm. Methods We performed a retrospective analysis of the medical records in a consecutive series of 50 patients who underwent direct-to-implant breast reconstruction using AlloDerm (n=31) or CryoDerm (n=19). We then compared the clinical course and postoperative outcomes of the two groups based on the overall incidence of complications and the duration of drainage. Results The mean follow-up period was 16 months. There were no significant differences in the overall incidence of complications (seroma, infection, skin flap necrosis, capsular contracture, and implant loss) between the two groups. Nor was there any significant difference in the duration of drainage. Conclusions CG CryoDerm has the merits of short preparation time and easy handling during surgery. Our results indicate that CG CryoDerm might be an alternative allograft material to AlloDerm in direct-to-implant breast reconstruction.

• Archives of Plastic Surgery
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• v.46 no.4
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• pp.330-335
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• 2019

Background The use of anatomic implants has improved the aesthetic results of breast surgery; however, implant malrotation is an uncommon, but serious complication of these procedures. Nevertheless, little research has explored implant adhesion. In this study, we investigated adhesion between the expander and the capsule. Methods Seventy-nine cases of immediate breast reconstruction via two-stage implant-based reconstruction performed between September 2016 and November 2017 were evaluated. Mentor CPX4 expanders were used in 14 breasts, and Natrelle expanders in 65. We analyzed areas of adhesion on the surfaces of the tissue expanders when they were exchanged with permanent implants. We investigated whether adhesions occurred on the cephalic, caudal, anterior, and/or posterior surfaces of the expanders. Results Total adhesion occurred in 18 cases, non-adhesion in 15 cases, and partial adhesion in 46 cases. Of the non-adhesion cases, 80% (n=12) were with Mentor CPX4 expanders, while 94.4% (n=17) of the total adhesion cases were with Natrelle expanders. Of the partial adhesion cases, 90.7% involved the anterior-cephalic surface. The type of tissue expander showed a statistically significant relationship with the number of attachments in both univariate and multivariate logistic regression analyses (P<0.001) and with total drainage only in the univariate analysis (P=0.015). Conclusions We sought to identify the location(s) of adhesion after tissue expander insertion. The texture of the implant was a significant predictor of the success of adhesion, and partial adhesion was common. The anterior-cephalic surface showed the highest adhesion rate. Nevertheless, partial adhesion suffices to prevent unwanted rotation of the expander.

• Archives of Plastic Surgery
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• v.51 no.1
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• pp.36-41
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• 2024

Background Among breast reconstruction methods, implant-based breast reconstruction has become the mainstream. However, periprosthetic infection is still an unresolved problem. Although published articles have revealed that limited use of antibiotics is sufficient to reduce infection rates, the number of surgeons still preferring elongated usage of antibiotics is not less. The aim of our study is to validate the appropriate duration of antibiotic use to reduce infection rate after implant-based breast reconstruction. Methods A retrospective study reviewed medical record of 235 patients (274 implants for reconstruction) who underwent prepectoral direct to implant breast reconstruction using acellular dermal matrix wrapping technique. Infection rates were analyzed for the patients administered postoperative prophylactic antibiotics until drain removal and those who received only perioperative prophylactic antibiotics for 24 hours. Results Of the 274 implants, 98 who were administered prophylactic antibiotics until drain removal had an infection rate of 3.06% (three implants) and 176 who received prophylactic antibiotics no longer than 24 hours postoperatively had an infection rate of 4.49% (eight implants). A total of 11 patients diagnosed with postoperative infection clinically, 8 were salvaged by antibiotic treatment, and 3 had implant removal and replacement with autologous flap. Postoperative antibiotic prophylaxis duration had no statistically significant effects in the risk of infection (p = 0.549). Conclusion The duration of prophylactic antibiotics after surgery was not related to infection risk. Further study with a large number of patients, randomized control study, and route of antibiotics is needed.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.2
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• pp.105-113
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• 2018

Purpose: The purpose of this study was to investigate the effects of the insertion depth of an immediately loaded implant on the stress distribution of the surrounding bone and the micromovement of the implant using the three-dimensional finite element analysis. Materials and methods: A total of five bone models were constructed such that the implant platform was positioned at the levels of 0.00 mm, 0.25 mm, 0.50 mm, 0.75 mm, and 1.00 mm depth from the crest of the cortical bone. A frictional coefficient of 0.3 and the insertion torque of 35 Ncm were simulated on the interface between the implant and surrounding bone. A static load of 178 N was applied to the provisional prosthesis with a vertical load in the axial direction and an oblique load at $30^{\circ}$ with respect to the central axis of the implant, then a finite element analysis was performed. Results: The implant insertion depth significantly affected the stress distribution on the surrounding bone. The largest micromovement value of the implant was $39.34{\mu}m$. The oblique load contributed significantly to the stress distribution and micromovement in comparison to the vertical load. Conclusion: Increasing the implant insertion depth was advantageous in dispersing the concentrated stress in the cortical bone and did not significantly affect the micromovement associated with early osseointegration failure.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.2
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• pp.225-243
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• 1991

In recent years immediate implantation has been tried by a few clinicians. This study placed IMZ implants in the rabbit femur with and without bony defects around the implant for simulating fresh extraction site. And one group with bony defects used porous hydroxyapatite ganules(HA) to fill if and the other group left the bony defects around the implant. The purpose of this study was to compare the shear bond strength and the bony contact and formation around the implant. Fifteen rabbits were divided into three groups and placed 10 IMZ implants to each group. Implant sites were surgically prepared with IMZ drills kit and implants were placed(Control), artificial bony defect was created with Apaceram drills kit around the implant sites and implants were placed(Experimental I), bony defect was filled with porous hydroxyapatite granules(Experimental II). Thereafter, rabbits were sacrificed at 8th week and specimens were prepared and pushout tested for shear bond strength of bone-implant interface immediately. Undecalcified and decalcified specimens were prepared with Vilanueva and hematoxylin-eosin stain for light microscopic finding. The results of this study were as follows. 1. In the control group, mean shear strength of bone-implant interface was $2.614{\pm}0.680$ MPa, experimental I was $0.664{\pm}0.322$ MPa, and experimental II was $2.281{\pm}0.606$ MPa. There was significant difference between control and experimental I, between experimental I and experimental II, but did not show significant difference between control and experimental II statistically. 2. In the bony formation surrounding IMZ implant of the three groups, that of cortical bone is more advanced than cancellous bone area. 3. In the histological findings of undecalcified specimens, control and experimental II showed more than 50% of bony or osteoid formation at the bony-implant interface. 4. In the histological findings of undecalcified specimens, experimental I showed less than 50% of bony or osteoid formation at the interface, and observed partial bony defect in the coronal zone. 5. In the experimental II group, were observed direct bony contact to hydroxyapatite granules, and infiltration of a few giant cells. 6. No inflammatory responses were seen around the titanium implants and the hydroxyapatite granules.

• Journal of Periodontal and Implant Science
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• v.36 no.3
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• pp.673-682
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• 2006

Recent study shows that implant design has a great impact on initial stability in bone. The ITI $TE^{(R)}$ implant, designed originally for immediate placement has a tapered/ cylindrical form which fits the anatomical shape of the natural alvelous or tooth root. The increased diameter at the collar region coupled with more threads lead to more bone contact and enhanced stability. The aim of this retrospective study is to evaluate the clinical use and the efficacy of recently introduced ITI TE implant with a new macro-design. The following results are compiled from 139 patients who received ITl TE implant surgery at the periodontal department. of Yonsei University Hospital between July 2002 and September 2005. 1. 139 patients received 173 ITl $TE^{(R)}$ implants in their maxilla and mandible (Mx 82, Mn 91). Posterior area accounted for 84% of the whole implant surgery, 2. In the distribution of bone quality, type III(41,0%) was the most, followed by type IV(41,0%) and type II (27.7%). As for the bone quantity, type B(43.9%) was the most, followed by type C(42.2%), type D(12.2%) and type A(1.7%). 3. 125 implants(83.9%) were treated by single crown, which accounted for the majority. 4, The total implant survival rate was 100% after a mean follow-up period of 21.2 months. This preliminary data with ITl $TE^{(R)}$ implant showed excellent survival rate although the majority of implants evaluated in this study were placed in the posterior region of the jaw and compromised sites.