• Restorative Dentistry and Endodontics
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• v.38 no.2
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• pp.59-64
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• 2013

Apical surgery cuts off the apical root and the crown-to-root ratio becomes unfavorable. Crown-to-root ratio has been applied to periodontally compromised teeth. Apical root resection is a different matter from periodontal bone loss. The purpose of this paper is to review the validity of crown-to-root ratio in the apically resected teeth. Most roots have conical shape and the root surface area of coronal part is wider than apical part of the same length. Therefore loss of alveolar bone support from apical resection is much less than its linear length.The maximum stress from mastication concentrates on the cervical area and the minimum stress was found on the apical 1/3 area. Therefore apical root resection is not so harmful as periodontal bone loss. Osteotomy for apical resection reduces longitudinal width of the buccal bone and increases the risk of endo-perio communication which leads to failure. Endodontic microsurgery is able to realize 0 degree or shallow bevel and precise length of root resection, and minimize the longitudinal width of osteotomy. The crown-to-root ratio is not valid in evaluating the prosthodontic prognosis of the apically resected teeth. Accurate execution of endodontic microsurgery to preserve the buccal bone is essential to avoid endo-perio communication.

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.4
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• pp.349-357
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• 2015

Edentulous patients with a severely resorbed mandible or maxilla often experience problems with conventional dentures, such as insufficient stability and retention, together with a decrease in chewing ability. Because of the good prognosis of dental implants, these patients can be successfully treated with implant-retained or implant-supported prosthesis. Ideally, a maximum number of implants of maximum length are placed in appropriate surgically prepared sites that are surrounded by a maximum amount of bone of favorable quality. The implants are favorably aligned faciolingually and mesiodistally to enhance optimal prosthodontic design. This article describes the clinical problems and complications encountered when treating a consecutive number of edentulous patients with osseointegrated implant-supported prostheses.

• The Journal of Advanced Prosthodontics
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• v.2 no.2
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• pp.58-60
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• 2010

Presurgical prosthetic treatment planning is critical for the success of the implant prosthesis. Inadequate treatment plan, due to insufficient discussion between prosthodontist, and surgeon, may result in poor prognosis. A 26-year-old male patient was referred for prosthodontic treatment after implant was placed in the area of teeth #17,16, 22, 25 and 27, without adequate discussion nor the treatment planning between oral surgeon and prosthodontist. It was found that the patient had two hopeless teeth, and a severely resorbed alveolar ridge. Additional tooth extraction was needed and the type of definitive prosthesis was shifted from fixed type to removable one. Proper pre-surgical treatment planning is essential for the good prognosis. Implant-supported removable prosthesis on milled bars may be a useful treatment option in patients with incorrect angled placement on severely resorbed alveolar ridge.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.4
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• pp.339-346
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• 2013

In case of missing of permanent teeth by trauma or innate defect, the decision of treatment modalities and application timing have an important effect on the prognosis of oral rehabilitation. In this case report, interdisciplinary approach between the orthodontic and prosthodontic treatment, the way to re-establish the collapsed occlusal vertical dimension, and implant prosthetic considerations will be discussed. Proper diagnosis on teeth and craniofacial skeleton was made prior to treatment and provisional restorations were used in regard of growth patterns of the patient. Finally, the edentulous areas were restored with fixed implant prostheses. Diagnosis, treatment rationale and prognosis will be discussed thoroughly.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.4
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• pp.332-338
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• 2013

Data collection including checking the problem list and analyzing the etiology cannot be overemphasized in full mouth rehabilitation cases. It is well reported that favorable prognosis of prosthodontic treatment depends on accurate diagnosis. Seventy seven year old female patient presented with chief complaints of chewing pain on maxillary and mandibular left premolars and unesthetic existing prosthesis. Clinical evaluation, radiographic examination and cast analysis were performed to gather comprehensive data and problem lists. Treatment planning was based on collected data and related articles. Abutment evaluation, prognosis depending on various types of prosthesis, and maintenance were considered as well. Occlusal vertical dimension was increased to solve esthetic dissatisfaction and insufficient interocclusal space. Patient adaptation was verified with provisional restorations followed by diagnostic wax up. Function, esthetics and occlusal stability were verified during 8 week follow-up period. Prosthodontic reconstruction based on systemic analysis, diagnosis, and treatment plan led to satisfactory result after delivery of definitive prosthesis.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.1
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• pp.8-11
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• 2001

Langerhans Cell Histiocytosis (LCH) is characterized by proliferation of Langerhans cells. The clinical manifestation varies from solitary bone lesion to multi-system, life threatening disorder. The younger the patient is and the more system is involved, the worse the prognosis is. The jaw is involved $10\sim20$ percent of all LCH and it is involved usually in early stage of LCH. In this case the patient is three years old girl who suffered from pain of whole mandibular body and histological examination confirmed the diagnosis LCH. She is referred to pediatrics and managed with combined chemotherapy. Due to the possibility of recurrence, we follow up the girl and she need orthodontic and prosthodontic treatment in the future because of the loss of lower left 2nd premolar. We report this case because early recognized LCH in dental hospital result in good prognosis.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.8 no.1
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• pp.36-44
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• 1999

No one really doubts that the hottest area of dentistry in 21st century would most likely be 'implant'. With the support of a vast amount of research, implant has been successfully and rapidly absorbed into the field of general dentistry including private practitioners. For teeth with hopeless(or refractory) periodontitis or periapical pathosis, with no hesitation most dentists would think extraction as the sole treatment option followed by prosthodontic replacement possibly including implant. Not many dentists would take Trasplantation/Replantation as another treatment option for a particular condition. Dentistry is often more focused on 'Restoration' than 'Preservation' of natural dentition. 'Biologic Implant' is obviously much closer to the concept of 'Preservation'. Many different types of biologic implant system have been introduced to clinical dentistry so far. Many of those have failed to earn reasonable acknowledgement despite of the clinical success they brought. For some reason biologic implant has rather been alienated for long time. RPI(Ring Pin Implant) is designed to improve the prognosis and success rate of transplanted/replanted teeth. RPI is a Ti-based custom made implant system. It is fabricated either by electric casting or milling process. The major feature RPI gas is the 'ring & hole' structure. The hole should be no less than 1mm diameter to allow bone bridge formation thru it. The ring structure and bone bridge formation creates anti-torque activity, which largely increases the 'initial stability' of the transplanted/replanted teeth. It is also reported that RPI is beneficial in the aspect of resisting root resorption following replantation/transplantation procedure.

• Journal of the Korean institute of surface engineering
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• v.40 no.4
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• pp.197-202
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• 2007

Fit of the restoration and its cementation procedure is crucial to both its short and long term prognosis. Marginal fit is affected by many variables during the fabrication process. These variables, being intrinsic properties of the materials or the clinical technique used, can cause changes in the size and shape of the definitive restoration. Even if all variables are controlled carefully, the seating of a restoration can still be affected due to insufficient space for the luting agent. The use of die spacer can reduce the elevation of a cast restoration of a prepared tooth, decreased seating time, improve the outflow of excess cement, and lower the seating forces. The purpose of this study was to evaluate the marginal fidelity according to die spacer application times and measurement site. Casting alloys were prepared and fabricated using non-precious metal at $950^{\circ}C$. Specimens are divided into four groups: I(die spacer painted casting for wax pattern), II(die spacer non painted casting for wax pattern). The specimens were cut and polished for marginal gap observation. The marginal gap was observed using scanning electron microscopy (SEM).

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.4
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• pp.352-358
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• 2011

Purpose: This study evaluated the prognosis and survival rate of SLA (Sandblasted, Large-grit and Acid-etched) implants and it also evaluated the prosthodontic complications and the associated factors. Methods: Twenty seven patients (14 men and 13 women, mean age: 54.9) who visited Chosun University Hospital Implant Center with the chief desire for placement of an implant in an edentulous area from March, 2008 to December 2008 and who received placement of a SLA implant ($Implantium^{(R)}$, Dentium Co., Korea) were selected for this study. Results: The average follow-up period was 15 months and the study was based on the treatment records, radiographs and clinical examinations. A total of 69 implant cases were retrospectively assessed for the width and length of the implant, the primary and secondary stability, the combined surgery, the employed bone graft material and barrier membrane, the status of the opposing tooth, implant failure and the prosthetic complications. During the follow-up period (average: 15 months), the accumulative survival rate of the 69 implants in 27 patients was 100%. Complications such as infection, sinusitis and fixture exposure after surgery were seen for 5 implants in 4 patients. Complications such as screw loosening, contact loosening and peri-implant gingivitis after prosthodontic treatment occurred in 7 cases (10.14%). Conclusion: This study reports placement of SLA implants may cause various complications, yet the final accumulative survival rate was 100%. The SLA implant ($Implantium^{(R)}$) has an excellent clinical survival rate and outcome.

• Journal of Dental Rehabilitation and Applied Science
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• v.16 no.2
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• pp.149-159
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• 2000

Occlusal disease is comparable to periodontitis in that it is generally not reversible. Occlusal disease, however, like periodontitis, often maintainable. It does itself to treatment and when restorative dentistry is utilized it becomes, in that sense, reversible. Moreover, a systematized and integrated approach will lead to a prognosis that is favorable and predictable. This approach facilitates development of optimum oral function, comfort, and esthetics, resulting in a satisfied patient. Such a systematized approach consists of four logical phase : (1) patient evaluation, (2) comprehensive analysis and treatment planning, (3) integrated and systematic reconstruction, and (4) postoperative maintenance. An integrated treatment plan is first developed on one set of diagnostic casts, properly mounted on a semiadjustable articulator using jaw relationship records. This is accomplished by using wax to make reconstructive modifications to the casts. These modified casts become the blueprint for planned occlusal changes and the fabrication of provisional restorations. The treatment goals are : (1) comfortably functioning temporomandibular joints and stomatognathic musculature, (2) adherence to the basic principle of occlusion advocated by Schuyler, (3) anterior guidance that is in harmony with the envelope of function, (4) restorations that will not violate the patient's neutral zone. This report shows the treatment procedures for a patient whose mandibular position has been altered due to posterior bite collapse. Migration of the maxillary anterior teeth had occurred, and the posterior occlusal contacts showed pathologic interference. Precise diagnosis using mounted casts was executed and prosthodontic reconstruction by the aid of an unconventional orthodontic correction on maxillary flaring was planned. An unconventional orthodontic correction can be accomplished by using preexisting natural teeth, which can be modified for use in active tooth movement or splinted together for orthodontic anchorage. This technique has an advantage over conventional fixed appliance orthodontic therapy because it can accomplish tooth movement concurrently with restorative and periodontal therapy. On occasion, minor tooth movement can be necessary to achieve the optimum occlusal scheme, crown form, and tooth position for the forces of occlusion to be displaced down the long axis of the periodontally compromised teeth. Once the occlusion, periodontal health, and crown contours for the provisional splinted restoration are acceptable, the final splinted restoration can be similarly fabricated, and it becomes an excellent orthodontic retainer.