A case of full mouth rehabilitation in patient with loss of vertical dimension and deep bite due to tooth wear / 대한치과보철학회지

The collapse of the posterior occlusion destroys the normal occlusal plane and causes excessive wear reducing the vertical dimension. Reduced vertical dimension of occlusion causes not only aesthetic and functional problems but also overloading on the temporomandibular joints and abnormalities of muscle nerve system. In order to improve the collapsed occlusal relationship, it is necessary to consider the change of the vertical dimension. It is necessary to make a precise diagnosis and analysis before the treatment and to evaluate the adaption of patient to the new vertical dimension of occlusion. A patient with excessive overbite often has occlusal problems of tooth wear and tooth eruption. Considering these considerations, overall prosthodontic restoration is required to solve the problem. A patient of 68 year old man in this case who suffered major tooth wear and maxillary posterior teeth loss was treated with elevation of vertical dimension of occlusion by maxillary removable dental prosthesis and mandibular fixed prosthesis.

Full mouth rehabilitation using removable partial denture in patient with loss of vertical dimension due to worn dentition / 대한치과보철학회지

Gradual attrition is a normal process of aging, but severe attrition causes occlusal disharmony, functional disorder and esthetic problems. The collapse of posterior support may cause attrition of anterior teeth, and loss of occlusal vertical dimension (OVD). And it induces the pathologic change of the TMJ, unaesthetic facial appearance and decreased masticatory function. In this case, 70 year-old male presented with decreased vertical dimension and esthetic problems due to worn dentition. Based on assessment of intraoral findings, diagnostic cast and radiographic examination, full-mouth rehabilitation with increase of OVD was planned. After 10 month follow-up, occlusal stability is maintained and through this procedure, satisfactory outcomes were achieved in esthetic and functional aspects.

Full mouth rehabilitation of the patient with crossed occlusion using removable partial denture restoration: A case report / 대한치과보철학회지

In removable partial denture with crossed occlusion, it is difficult to meet the satisfaction of patient due to variable movement of denture and unfavorable stability under loading. In a case with few unilaterally teeth remaining, additional treatments such as implantation or residual root are required to assure bilaterally stable support. However, due to the medical condition of the patient with hypertension, angina and old age etc., removable partial denture was planned as treatment in this case. Proper diagnosis, accurate analysis and full understanding of the adaptation for neuromuscular system are necessary to recover the vertical dimension of patient from a decreased vertical dimension due to crossed occlusion.

Full mouth rehabilitation in patient with loss of vertical dimension and deep bite due to worn dentition / 대한치과보철학회지

Gradual occlusal attrition is a normal process of aging. However, severe attrition causes pathogenic pulp, occlusal disharmony, functional disorder and esthetic problems. Alteration of vertical dimension should be considered for space regaining for tooth restoration, esthetic improvement or correction of occlusal relationship. Vertical dimension should be determined within the range of minimal invasive process satisfying patient's esthetic requirements and operator's functional goal. And patient's adaptation to newly determined vertical dimension should be assessed simultaneously. Deep overbite is not a simple problem of overbite, instead it is an usually complicated problem with anterior-posterior occlusal relationship. Considering these facts, appropriate restoration of edentulous part as well as improvement of anterior-posterior relationship should be performed to solve this fundamental problems. In this study, a 67 year-old male patient with many worn teeth and loss of posterior teeth was treated with removable partial denture at edentulous mandibular area to increase vertical dimension and fixed prostheses at dentulous maxillary and mandibular area. With these treatments, we attained a satisfactory result in functional and esthetic aspects as a report case.

A retrospective study on related factors affecting the survival rate of dental implants

PURPOSE: The aim of this retrospective study is to analyze the relationship between local factors and survival rate of dental implant which had been installed and restored in Seoul Veterans Hospital dental center for past 10 years. And when the relationship is found out, it could be helpful to predict the prognosis of dental implants. MATERIALS AND METHODS: A retrospective study of patients receiving root-shaped screw-type dental implants placed from January 2000 to December 2009 was conducted. 6385 implants were placed in 3755 patients. The following data were collected from the dental records and radiographs: patient's age, gender, implant type and surface, length, diameter, location of implant placement, bone quality, prosthesis type. The correlations between these data and survival rate were analyzed. Statistical analysis was performed with the use of Kaplan-Meier analysis, Chi-square test and odds ratio. RESULTS: In all, 6385 implants were placed in 3755 patients (3120 male, 635 female; mean age 65 +/- 10.58 years). 108 implants failed and the cumulative survival rate was 96.33%. There were significant differences in age, implant type and surface, length, location and prosthesis type (P.05). CONCLUSION: Related factors such as age, implant type, length, location and prosthesis type had a significant effect on the implant survival.

Review of the developmental trend of implant surface modification using organic biomaterials / 대한치과보철학회지

PURPOSE: This study aims to evaluate and prospect for current research trend and developmental perspectives via analyzing recent biomaterial coated-implants study. MATERIALS AND METHODS: To investigate each subject respectively, several biomaterials that are using for implant surface coating were set as 'keywords'. By these keywords, major research groups in each subject were chosen, and research trend of them was analyzed. Trend of In vivo studies that examined selected biomaterials were analyzed to evaluate commercial potential. RESULTS: The collagen research accounted for 40% of total implant study, which was the highest, and fibronectin, BMPs (bone morphogenetic proteins) and RGD (Arg-Gly-Asp) peptides followed, which were ranked in descending order. Furthermore, figures of all four research subjects were also increased with time, especially a sharp increase in RGD research. According to the results of major research group, collagen that was combined with other organic and inorganic biomaterials was mostly examined, rather than using collagen only. Major research groups investigating BMPs mostly focused on rhBMP-2. In animal studies, collagen was used as resorbable membrane in guided bone regeneration (GBR) or drug carrier, while BMPs were used with bone graft materials or coating material for titanium implant surface. CONCLUSION: There is not consistency of results even in identical subjects research field. Many studies are ongoing to optimize combination between mechanical surface treatment and biomaterials such as extracellular matrix component and growth factors.

Effect of platelet-rich plasma on bone regeneration in ovariectomized osteoporotic rats / 대한치과보철학회지

PURPOSE: The aim of this experimental study is to observe the effect of platelet-rich plasma (PRP) on early bone regeneration of rats both in normal condition and in osteoporosis induced by ovariectomy. MATERIAL AND METHODS: Total 40 Sprague-Dawley female rats were divided into 4 groups. A 8-mm-diameter calvarial critical-sized defect (CSD) was made by drilling with trephine at the center of calvaria in cranium of every rat. Every CSD was augmented with an osteoconductive synthetic alloplastic substitute (MBCP(TM)) and PRP as follows. Group A; 10 non-ovariectomized rats grafted with only MBCP(TM). Group B; 10 non-ovariectomized rats grafted with MBCP(TM)and PRP. Group C; 10 ovariectomized rats grafted with only MBCP(TM). Group D; 10 ovariectomized rats grafted with MBCP(TM) and PRP. At 4 weeks after graft, every rat was sacrificed. And histomorphometric analysis was performed by measuring calcified area of new bone formation within the CSD. RESULTS: Comparing four groups, results were obtained as follows. 1. In non-ovariectomized groups, PRP showed a positive effect somewhat but not significant (P > .05). 2. In ovariectomized groups, PRP showed a positive effect significantly (P .05). CONCLUSION: Within the limitation of this study, it can be concluded that PRP in combination with an osteoconductive synthetic alloplastic substitute has an effect on bone regeneration more significantly in ovariectomized osteoporotic rats than in normal rats.