• The Journal of Korean Academy of Prosthodontics
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• v.30 no.4
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• pp.541-564
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• 1992

The purpose of this experiment was to study the effect of implantation of the dense hydroxyapatite (HA) granules$(Apaceram^{(R)})$ in the fresh extraction sockets on the residual ridge resorption in normal and induced diabetic rabbits. Sixty-four white rabbits, weighing 3.0kg, were utilized in this study and they were divided into four group : group 1-sixteen normal rabbits without filling HA granules, group 2-sixteen normal rabbits with filling HA granules, group 3-sixteen diabetic rabbits without filling HA granules, group 4-sixteen diabetic rabbits with filling HA granules. HA granules were filled immediately after extraction in the extraction sockets of the mandibular left 1st, 2nd, and 3rd molar in group 2 and 4, and no HA granules were filled in group 1 and 3. The calculation of residual ridge resoption was done at 4th week, 8th week, 12th week, and 16th week after surgery, and histologic examination was performed to study healing process at 2nd week, 4th week, 8th week, and 16th week after surgery. The results were as follows : 1. The amount of residual ridge resorption was largest in group 3, and smallest in group 2 in every interval. There was no statistically significant difference between group 1 and 4. 2. In all groups, the amount of residual ridge resorption was high until 4th week after surgery, but the rate of residual ridge resolution slowly decreased after 4th week 3. There was more active healing process in group 1 and 2 than in group 2 and 4. 4. According to filling of HA granules, there was no difference in the amount of new bone formation, but direct contact could be observed between newly formed bone and HA granules in group 2 and 4. 5. Group 1 and 3 showed marked bone resorption and adipose marrow from 8th-16th week after surgery, but group 2 and 4 did not show maeked bone resolution, and showed fibrous tissue and a little adipose tissue among trabeculae from 8th week.

• Journal of Korean Dental Science
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• v.4 no.2
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• pp.59-66
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• 2011

Purpose: This research sought to determine the resorption rate of bone grafted to the maxillary sinus according to the grafted material's type, patient's age, systemic disease, implant size, site of implant placement, and residual ridge height. Materials and Methods: This research targeted 24 patients who had immediate Osstem$^{(R)}$ implant (US Plus$^{(R)}$) placement after bone graft. The panorama was taken before the surgery, after the surgery, and 6 months after the surgery. Vertical height change and resorption rate of the grafted bone were measured with the same X-rays and compared. The influence of the following factors on the grafted bone material's resorption rate was evaluated: grafted material type, patient's age, systemic disease, implant size, site of implant placement, and residual ridge height. Results: Patients in their 40s had $34.0{\pm}21.1%$ resorption rate, which was significantly higher compared to the other age groups (P<0.05). There was no significant relationship between systemic disease and grafted bone resorption. There was no significant relationship between implant size (diameter, length) and grafted bone resorption. There was no significant relationship between the site of implant placement and grafted bone resorption. The ramal bone-grafted site was significantly more resorbed than the ramal bone/Bio-Oss$^{(R)}$-grafted site, maxillary tuberosity bone/Bio-Oss$^{(R)}$-grafted site, and ramal bone/maxillary tuberosity bone/Bio-Oss$^{(R)}$-grafted site (P<0.05). There was no significant difference in the grafted bone resorption rate in the sinus between more than 4 mm and less than 4 mm residual ridge heights. After an average of 6 months, a second surgery was done; given an average follow-up of 1.9 years, the success rate and survival rate of the implant were 96.9% and 98.4%, respectively. Conclusion: These results indicate that the bone resorption rate of grafted bone among patients in their 40s is higher compared to patients in their 50s and over, and that only autogenous bone (ramus) shows higher resorption rate than the mixed graft of autogenous bone and xenogenous graft (Bio-oss) after maxillary sinus graft.

• Journal of Dental Rehabilitation and Applied Science
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• v.39 no.4
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• pp.214-221
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• 2023

In order to fabricate stable dentures in patients with severe resorption of residual ridges, various factors must be considered. One of them is the neutral zone, which is defined as the potential region in which the pressure of the tongue outward in the oral cavity and the pressure of the cheeks and lips directed inward from the outside of the oral cavity equalize during functioning. In patients with severe ridge resorption, if the teeth are usually arranged above the residual ridge, the teeth are located on the lingual side rather than the original position. Therefore, the functional space of the tongue is invaded, the tongue is positioned backward, and the sealing of the lingual border is broken, which acts as a factor reducing the maintenance of denture. In addition, it is also important for the stability of dentures to assume an interalveolar crest line connecting the maxillary and mandibular ridge crests, and to arrange the maxillary and mandibular artificial teeth to match the masticatory force to the interalveolar crest line. Therefore, good clinical results were obtained by fabricating dentures for the patient with poor alveolar residual ridge using neutral zone impression and ridge relationship analysis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.6
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• pp.575-579
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• 2006

Purpose : The purpose of this study was to evaluate peri-implant bone loss and implant success on anterior maxillary alveolar ridges and Compare Class III and Class IV ridges in the aspect of peri-implant bone loss. Material and Methods : 14 patients (aged 21 to 68, 6males and 8females), who lacked maxillary anterior teeth and were installed from January 2000 to April 2003 at Samsung Medical Center, were selected. The type of implant used included 30 $Br\ddot{a}nemark$ implant. They were taken with digital tomographic and conventional intraoral radiographic examinmation, and were treated with implant installaion without bone augmentation. The peri-implant bone resorption was measured at the mesial and distal aspect of implant on the conventional intraoral radiographs. Results : The study classified the anterior maxillary alveolar ridge and measured peri-implant bone resorption from the period of implant installation to the 2nd year after functional loading radiographically. The study revealed no statistically significant difference between two groups, which was classified by its morphology. The average bone resorption on healing period before loading was 0.18mm and 0.18mm, the 1st year of loading period, 0.77 mm and 0.84mm, and on the 2nd year of loading period, 0.07mm and 0.06mm, respectively on both Class III and class IV. Conclusion : In the knife edge form of anterior maxillary residual ridges(Class IV), implant placement without ridge augmentation does not have significant difference with that of Class III alveolar ridge in the concern of Implant success after 2 year functional loading period in the aspect of peri-implant bone resorption radiographically.

• Imaging Science in Dentistry
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• v.39 no.1
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• pp.19-25
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• 2009

Purpose: To longitudinally observe the healing process of extracted socket and the alterations of the residual ridge in healthy adult dogs using cone beam CT (CBCT). Materials and Methods: The mandibular premolars of two beagle dogs were removed and the extraction sites were covered with the gingival tissue. CBCTs (3D X-ray CT scanner, Alphard vega, Asahi Co.) were taken at baseline and at 1 week interval for 12 weeks. Radiographic density of extracted wounds was measured on normalized images with a custom-made image analysis program. The amount of alveolar crestal resorption after the teeth extraction was measured with a reformatted three-dimensional image using CBCT. Bony healing pattern of extracted wound of each group was also longitudinally observed and analyzed. Results: Dimensional changes occurred during the first 6 weeks following the extraction of dogs' mandibular premolars. The reduction of the height of residual ridge was more pronounced at the buccal than at the lingual aspect of the extraction socket. Radiographic density of extracted wounds increased by week 4, but the change in density stabilized after week 6. New bone formation was observed at the floor and the peripheral side of extracted socket from week 1. The entrance of extracted socket was sealed by a hard-tissue bridge at week 5. Conclusion: The healing process of extracted wound involved a series of events including new bone formation and residual ridge resorption.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.4
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• pp.426-433
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• 2013

When restoring edentulous patients with lower complete denture, the smaller supportive and retentive area of mandible can lead to poor support and stability, denture dislodgement and pain resulting discomfort. In this situation, implant prosthesis can improve esthetics, stability and occlusal force. Whereas, patients with a upper complete denture can adjust more easier because of palate. Therefore, it is suggested to rehabilitate fully edentulous patients with lower implant-supported, upper complete denture as one of the treatment options. So, we are going to report the case and literature review about how the lower implant prosthesis opposing to upper complete denture affects the bone resorption of maxillary residual ridge.

• The Journal of the Korean dental association
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• v.55 no.1
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• pp.90-95
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• 2017

As residual ridge resorption occurs, complete dentures tend to become loose. Denture relining and rebasing are an essential element for improving a denture's stability and prevention side effect such as sore spot, epulis fissuratum. This paper focuses about health insurance is available for maintenance of complete denture and, methods of relining or rebasing.

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.3
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• pp.242-252
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• 2015

Implant overdenture treatment using several solitary attachment systems on mandibular edentulous patients. Most patients with severe residual ridge resorption report significantly more problems adapting to their mandibular denture due to a lack of comfort, retention, stability and to the inability to chew and eat. Recent scientific studies carried out over the past decade have determined that the benefits of a mandibular implant overdenture are sufficient to get retention and stability. Therefore, overdenture with implants on the mandible and attachments are considered as a treatment of choice as a favorable treatment. In this cases, with consideration for jaw relation, level of bone loss, facial support and economic factor, edentulous patients with severe residual ridge resorption are rehabilitated by complete denture on maxilla and two-implants overdenture using several solitary attachment systems on mandible.

• Journal of Periodontal and Implant Science
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• v.47 no.6
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• pp.381-387
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• 2017

Purpose: The aim of this study was to evaluate volumetric and histologic changes in edentulous alveolar ridge areas after ridge preservation using basic fibroblast growth factor-2 (bFGF-2) in combination with collagenated biphasic calcium phosphate (BCP). Methods: The experiments were performed in 6 adult male beagle dogs. The following 3 groups were created: 1) ridge preservation with bFGF-2 and collagenated BCP (experimental group), 2) ridge preservation with collagenated BCP (positive control group), and 3) a negative control group in which no ridge preservation procedure was performed. Volumetric change analysis was performed using an optical scanner and casts. Histological observations were made using light microscopy. Results: After the initial swelling subsided, the magnitude of the volumetric change in the experimental group and positive control group was smaller than in the negative control group. In the experimental group, a distinct trend was observed for the resorption of residual bone and collagen fibers at 4 weeks and for more mature bone and faster healing at 12 weeks. Conclusions: Based on the findings of the present study, bFGF-2 may be considered for use as a therapeutic molecule in ridge preservation procedures.

• The Journal of the Korean dental association
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• v.53 no.5
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• pp.348-359
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• 2015

Objective: The aim of this study was to determine the effect of multi-layer of a collagen membrane alone or loaded rhBMP-2 on the buccal plate for ridge preservation after tooth extraction. Material and methods: Following bilateral extraction of the maxillary 1st and 3rd premolars in five dogs, rhBMP-2 loaded collagen membrane was applied to the buccal plates at the 1st premolar and collagen membrane only was applied to the buccal plates at the 3rd premolar unilaterally. The collagen membranes applied in the experimental groups were piled into four layers. The corresponding sites of the contralateral side healed naturally. After 3months of healing, the animals were sacrificed. Radiographic and histologic analyses were performed. Results: There was no significant difference in the healing of extraction socket at both 1st and 3rd premolars. In microcomputed tomography, the widths of the residual ridge of the experimental groups were similar with the controls. Histologically, the experimental groups did not exhibit different pattern compared to the controls regardless of the addition of rhBMP-2. Conclusion: Layering of the collagen membrane with or without rhBMP-2 on the buccal plate failed to show the effectiveness in dimensional preservation of the extraction socket.