• Journal of the Korean Academy of Esthetic Dentistry
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• v.30 no.2
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• pp.102-111
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• 2021

Implant placement in the anterior region is performed in several stages, and harmonization of both hard and soft tissues is essential. In addition, adequate esthetic and functional evaluations are necessary in the process of transitioning from the provisional to the final prosthesis to attain patient satisfaction. Although gingiva can be molded in the anterior region, depression in the occlusal view can yield good results through the augmentation procedure. However, the harvesting of connective tissue from the palate is not suitable for various reasons, such as postoperative discomfort and intraoperative bleeding. Compared to the palatal area, the harvesting of connective tissue from the maxillary tuberosity can easily result in relatively thick tissue and quick healing of the donor site, thus proving to be a good modality for graft procedures. The purpose of this report is to examine the relevant evidence from previous studies and evaluate the process of soft tissue augmentation through a case presentation.

• Journal of Dental Rehabilitation and Applied Science
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• v.25 no.3
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• pp.255-265
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• 2009

Recently many studies have been published on application of immediate loaded implants. However, the immediate loading protocol has not been well documented. The purpose of the present study was to evaluate the stress distribution between bone-implant interfaces and the effect of implant length in the anterior maxilla using 3 dimensional finite element analyses. The diameter 4.0 mm threaded type implants with different length(8.5 mm, 10.0 mm, 11.5 mm, 13.0 mm, 15.0 mm) were used in this study. The bone quality of anterior maxillary bone block was assumed to D3 bone. Bone-implant interfaces of immediately loaded implant were constructed using a contact element for simulating the non osseointegration status. For simplification of all the processing procedures, all of the material assumed to be homogenous, isotropic, and linearly elastic. The 178 N of static force was applied on the middle of the palatoincisal line angle of the abutment with $120^{\circ}$ angle to the long axis of abutment. Maximum von Mises stress were concentrated on the labial cortical bone of the implant neck area, especially at the cortical-cancellous bone interfaces. Compared the different length, highest peak stress value was observed at the 8.5 mm implants and the results indicated a tendency towards favorable stress distribution on the bone, when the length was increased. Presence of cortical bone was very important to immediate loading, and it appears that implants of a length more than 13 mm are preferable for immediate loading at the anterior maxilla.

• The korean journal of orthodontics
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• v.39 no.3
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• pp.146-158
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• 2009

Objective: The purpose of this study was to reveal the position of the incisive foramen in relation to the incisive papilla and cusp tips. Methods: Plaster models and CT images of 25 adult orthodontic patients were used to measure the width of the incisive canal and positions of the anterior and posterior borders of the incisive foramen in relation to the incisive papilla. Results: The palatal surface distance from the interdental papilla between the maxillary central incisors to the posterior border of the incisive foramen along the palatal surface was 1.7 fold of the distance from the interdental papilla between the central incisors to the posterior border of the incisive papilla. The distance between the posterior border of the incisive papilla and posterior border of the incisive foramen along the palatal surface was 6.15 ${\pm}$ 1.75 mm. The anteroposterior position of the posterior border of the incisive foramen was slightly anterior to the lingual cusp tips of the maxillary 1st premolars. The width of the incisive foramen was 4.03 ${\pm}$ 0.64 mm, therefore it is recommended to position the mini-implant more than 3 mm laterally when placing a mini-implant lateral to the incisive foramen, from the center. Conclusions: These results can be used as a reference in presuming the position of the incisive foramen when placing mini-implant in the anterior palate area.

• The Journal of the Korean dental association
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• v.47 no.10
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• pp.669-676
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• 2009

Purpose : Anterior region is crucial area for esthetic implant restoration. However, the alveolar process undergoes atrophy after removal of teeth and creates unfavorable situation for implant installation. The knowledge of the thickness of alveolar bone is required to estimate and expect the bone resorption after extraction. The aim of this study is to measure facial, palatal and faciopalatal bone thickness on maxillary anterior teeth. Methods : Facial, palatal, and faciopalatal bone thickness were measured on the computed tomography (CT) images from 57 patients, using an image analyzer program (Ondemand$3D^{(R)}$, Cybermed, Seoul, Korea). Results : The thickness of facial bone in incisors, lateral incisors and canines were less than 1 mm. The thickness of facial bone increased from anterior to posterior region and the thickness of palatal bone increased from posterior to anterior region. Conclusion : The measurement can be used for planning implant surgery before extraction. CT has are clinically useful in the evaluation of thickness of alveolar bone.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.2
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• pp.152-159
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• 2016

Implant fixed prosthesis for the complete edentulous maxilla provides significant benefits in the aspects of functions and esthetics compared with the conventional denture. Implant supported fixed prosthesis are totally supported by implant, and thus stabilizes the prosthesis to the maximum degree as possible. Also, the improved retention and stability of fixed prosthesis enhance patients' psychological and psychosocial health. This clinical presentation describes a maxillary full arch implant-supported fixed prosthesis in complete maxillary edentulous patient who showed vertical and horizontal alveolar bone resorption in the anterior ridge. To rehabilitate the esthetics and proper lip support, the zirconia framework was fabricated and the pink porcelain was veneered to reproduce the natural gingival tissue. After 9 months of follow up, the restorations were maintained without complications and the patient was satisfied with the restoration both functionally and esthetically.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.6
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• pp.570-578
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• 2006

A severely atrophic maxilla may disturb the proper implant placement. The various bone graft techniques are required for simultaneous or delayed implantation in the cases of atrophic alveolar ridges. We present 11 consecutive patients treated with simultaneous implantation using the autogenous inlay and/or onlay bone grafts from iliac crest to the floor of the maxillary sinus and the alveolar crest. In the cases of atrophic maxilla, a total 69 implants were simultaneously placed with autogenous iliac bone graft. 40 fixtures were inserted in the sinus floor simultaneously with subantral block bone graft, the other 29 fixtures were placed in the anterior or premolar areas with block or particulate bone graft. The vertical alveolar bone height was measured with Dental CT at the preoperation and 6 months postoperation. Moreover, the implant stability quotients (ISQ) were measured by $Osstell^{TM}$ during second implant surgery at 6 months later of first implantation. All implants were obtained successful osseointegration with the grafted bone. The mean vertical increases were 3.9mm in the anterior ridges and 12.8mm in the posterior ridges. During the second implant surgery, mean ISQ were 62.95 in the anterior ridge and 61.32 in the posterior ridge. We concluded that the simultaneous implantation with autogenous iliac bone graft were stable and available methods for severely atrophic maxilla.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.4
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• pp.353-360
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• 2007

In a one-stage approach, where the implant installation is performed simultaneously with the iliac bone graft, various complications are observed. The observed complications are as follows; severe bone resorption at the maxillary anterior region and the area adjacent to the nasal cavity, shortage of soft tissue to cover the augmented alveolar bone, difficulties with oral hygiene care caused by the diminished vestibular space and non-esthetic prosthesis. These are good reasons for choosing the two-stage approach over the one-stage approach in spite of all the advantages it has, and should be taken into careful consideration when diagnosing and planning treatment using the one-stage approach.

• Journal of Periodontal and Implant Science
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• v.36 no.1
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• pp.147-154
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• 2006

Surgical intervention in the posterior maxillary region requires detailed knowledge of maxillary sinus anatomy and the possible anatomical variations. This study evaluated the incidence, location of maxillary sinus septa by using radiographic (panoramic radiography and computed tomography) findings and comparison of panoramic radography with CT in antral anatomical variation. This study was based on data from 70 sinuses in partial dentate maxilla. The sample consisted of 61 patients(25 women and 36 men, with ages ranging between 19 and 77 years and a mean age of $49.4{\pm}11.3$ years) who were being treatment-planned to receive implant-supported restorations. First, the panoramic images were examined for the presence of antral septa by radiologist and examiner who don't know about CT findings. And incidence of antral septa was evaluated using an axial plane of CT image. The incidence of septa was compared between panoramic radiography and CT. The accuracy of the incidence was compared between radiologists and dentists. A total of 20 septa were found in 70 sinuses on CT image and the prevalence of one or more septa per sinus was found to be 28.6%. The assumed incidence of septa on panoramic radiography was $27.6%{\pm}2.2%$ in radiologist and $31.9%{\pm}5.8%$ in dentists. Erroneous diagnosis rate was 11.42% in radiologist and 15.96% in dentists. 40% of antral septa were located in the anterior(premolar) region, 30% of septa were located in the middle(first molar) and posterior(second molar) region separately. Prior to implant placement, it seems appropriate to consider panoramic radiography as a standard radiographic examination and periapical radiographs may be used to complete the findings in regions not sharply depicted in the panoramic radiograph. And cross-sectional imaging should be used in sites with severe bone loss and close proximity of the maxillary sinus.

• The korean journal of orthodontics
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• v.42 no.6
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• pp.280-290
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• 2012

Objective: This study aimed to compare the effects of conventional and orthodontic mini-implant (OMI) anchorage on tooth movement and arch-dimension changes in the maxillary dentition in Class II division 1 (CII div.1) patients. Methods: CII div.1 patients treated with extraction of the maxillary first and mandibular second premolars and sliding mechanics were allotted to conventional anchorage group (CA, n = 12) or OMI anchorage group (OA, n = 12). Pre- and post-treatment three-dimensional virtual maxillary models were superimposed using the best-fit method. Linear, angular, and arch-dimension variables were measured with software program. Mann-Whitney U-test and Wilcoxon signed-rank test were performed for statistical analysis. Results: Compared to the CA group, the OMI group showed more backward movement of the maxillary central and lateral incisors and canine (MXCI, MXLI, MXC, respectively; 1.6 mm, p < 0.001; 0.9 mm, p < 0.05; 1.2 mm, p < 0.001); more intrusion of the MXCI and MXC (1.3 mm, 0.5 mm, all p < 0.01); less forward movement of the maxillary second premolar, first, and second molars (MXP2, MXM1, MXM2, respectively; all 1.0 mm, all p < 0.05); less contraction of the MXP2 and MXM1 (0.7 mm, p < 0.05; 0.9 mm, p < 0.001); less mesial-in rotation of the MXM1 and MXM2 ($2.6^{\circ}$, $2.5^{\circ}$, all p < 0.05); and less decrease of the inter-MXP2, MXM1, and MXM2 widths (1.8 mm, 1.5 mm, 2.0 mm, all p < 0.05). Conclusions: In treatment of CII div.1 malocclusion, OA provided better anchorage and less arch-dimension change in the maxillary posterior teeth than CA during en-masse retraction of the maxillary anterior teeth.

• The Journal of the Korean dental association
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• v.56 no.5
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• pp.263-276
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• 2018

Long-term survival and prognosis of narrow-diameter implants have been reported to be adequate to consider them a safe method for treating a deficient alveolar ridge. The objective of this study was to perform case report of narrow-diameter implants with a trapezoid-shape in anterior teeth alveolar bone. A 50-year-old male patient presented with discomfort due to mobility of all of the maxillary teeth and mandibular incisors. Due to destruction of alveolar bone, four anterior mandibular teeth were extracted. Soft tissue healing was allowed for approximately 3 months after the extraction, and a new design of implant placement was planned for the mandibular incisor area, followed by clinical and radiological evaluation. Implant placement was determined using an R2GATE surgical stent. The stability of the implants was assessed by ISQ measurements at the first and second implant surgery and after prosthetic placement. At 1 and 3 months and 1 year after implantation of the prosthesis, clinical and radiological examinations were performed. Another 50-year-old male patient presented with discomfort due to mobility of the mandibular central incisors. For the same reason as in the first patient, implant placement was carried out in the same way after extraction. ISQ measurements and clinical and radiological examinations were performed as in the previous case. In these two clinical cases, 12 months of follow-up revealed that the implant remained stable without inflammation or additional bone loss, and there was no discomfort to the patient. In conclusion, computer-guided implant surgery was used to place an implant in an optimal position considering the upper prosthesis. A new design of a narrow-diameter implant with a trapezoid-shape into anterior mandibular alveolar bone is a less invasive treatment method and is based on the contour of the deficient alveolar ridge. Through all of these procedures, we were able to reduce the number of traumas during surgery, reduce the operation time and total treatment period, and provide patients with more comfortable treatment.