• The Journal of the Korean dental association
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• v.42 no.1 s.416
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• pp.7-14
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• 2004

Molar extrusion is a quite common problem in prosthodontic patients. It is caused due to the loss or infraocclusion of opposing teeth. A more conservative approach than reduction of the coronal part of extruded tooth is to intrude the malaligned molar orthodontically. Several authors have presented the cases of molar intrusion, by cither removable or fixed appliances. However, the design of those appliances was complex so that many teeth were included as an anchorage unit. This increased the patient's discomfort inevitably. Moreover, the results could be unpredictable. Instead of these conventional methods, skeletal anchorage has been suggested for ideal force system to intrude a molar without any side effects. Many recent clinical reports presented the cases using microscrew or miniplate as a direct anchorage, which included some limitation. The purpose of this report is to introduce the indirect skeletal anchorage for intrusion of extruded maxillary molar.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.2
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• pp.252-259
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• 2010

Trauma commonly leads to ankylosis for the tooth whose periodontal ligaments have been injured. In growing patients, an ankylosed tooth can disrupt alveolar development, resulting in infraocclusion of the affected tooth. Consequently, this causes aesthetic problems during adolescence, interferes with prosthetic treatment due to the inclination of adjacent teeth, and complicates orthodontic dental movement. When the infraoccluded ankylosed tooth is extracted, a considerable amount of alveolar bone is lost, especially in the maxillary anterior region. Moreover, depression of the thin buccal alveolar bone compromises aesthetic restoration. In order to prevent alveolar bone loss, the ankylosed tooth should be treated by decoronation. In the present study, the traumatically injured maxillary incisors of 9-year-old and 10-year-old patients that present infraocclusion accompanied by ankylosis were treated with decoronation procedures. Decoronation procedures were performed when the affected teeth were 2-3 mm below relatively to the adjacent teeth. Moreover, the patients were treated before they get to 16 years old considering the maximum growth peak of the korean adolescents. As the results, there are favorable clinical results associated not only with preservation of horizontal alveolar volume but also with increase in vertical alveolar height after decoronation in growing individuals.

• Journal of Dental Rehabilitation and Applied Science
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• v.23 no.1
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• pp.21-30
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• 2007

Despite of the successful clinical performance of implants, it is still lacking of the knowledge of changes in implant occlusion. The purpose of this study was to evaluate the changes of infraocclusal contact after clinical occlusal function of implant. Twenty patients(38 implants) were recalled during 10 months after placement of implant prosthesis. Occlusion changes were investigated at placement, placement 1 months, 4 months and 10 months serially with silicone bite material and T-Scan II sensor. Bony changes were also evaluated with periapical radiographs. The changes of silicone thickness and T-Scan II sensored areas were statistically analyzed with repeated measured ANOVA and the Scheffe's post-hoc test at the 95% significance level. The following results have been made based on this study: 1. Alveolar bone loss was within 0.20mm and it was generally concluded within physiologic level. 2. There were no statistically significant differences in the thickness changes of silicone material at 1 month and 4 months of occlusal function. However, there was statistically significant difference at 10 months of occlusal function (p<0.05). 3. There was no statistically significant difference in changes of occlusal contact area in T-Scan II at 1 month and 4 months of occlusal function, but there was statistically significant difference at 10 months of occlusal function (p<0.05). Conclusively, as time goes by, implant occlusion to be formed infraocclusion was to be far close and increased occlusal contact. However, it was not observed destructive bone resorption in periapical radiographs and any other side effects.

• Journal of Dental Rehabilitation and Applied Science
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• v.33 no.2
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• pp.143-153
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• 2017

One of the common complications of dental injury is tooth ankylosis. Unlike adults, when tooth ankylosis occurs in the adolescents, ankylosis interfered the growth of the adjacent alveolar bone, resulting in the developmental failure of the alveolar bone and subsequent open bite. The most common treatment option for ankylosed tooth is extraction. However, when prognosis of ankylosed tooth after extraction is expected to be poor due to severity of infrapositioning or prosthetic replacement cannot be performed immediately, various treatment options should be considered. This report suggests multidisciplinary treatment that might bring functionally and esthetically favorable result included alveolar bone distraction osteogenesis and decoronation of ankylosed maxillary anterior tooth with orthodontic and prosthetic treatments.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.4
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• pp.613-618
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• 2009

Impacted molars are not usual with the prevalence rate of less than 1%, however problems such as infraocclusion, extrusion of the opposite tooth and lack of space are caused. If molars are impacted, radiographic check-up and observations are needed as they play an important role in skeletal development and mastication. Causes of impaction are underdevelopment of roots, supernumerary teeth, cysts, odontomas, ankylosis and etc. In our first case, we present impacted molar which was surgically exposed and orthodontically traded. As the developmental state of the root was less than half at first visit, we observed until the root was 2/3 in its length and traction was carried out. The second case is orthodontic traded molar with compleate enucleation of the existing cysts. When trading impacted molars, direct bonding of attachments to the tooth and light continuous forces are recommended so as to ankylosis, external absorption and periodontal attachment loss avoid. Fixed appliances tract the teeth on arch and obtain eruption spaces without patient's cooperation. We report surgically exposed and orthodontically traded molars which resulted in good occlusion and patients satisfaction.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.3
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• pp.444-449
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• 2002

The term 'impaction' is used to designate a tooth which remains unerupted in the jaw beyond the time at which it should normally be erupted. The main causal factors are local (lack of space, ectopic positions of teeth, supernumerary teeth, cyst, the occurrence of infectious process in the eruption path, traumatic facial injury etc.). Systemic and genetic disorders, however, may have primary failure of eruption and retarded eruption as additional symptoms (cleidocranial dysplasia, osteopetrosis etc.). Most cases of impacted teeth reported in the literature are of permanent teeth. The absence of primary teeth occur rarely whereas impaction of second primary molars is more numerous than all other impactions. Impaction due to primary failure of eruption must be distinguished from the secondary infraocclusion. The etiology of impaction of primary teeth is probably related to early ankylosis of primary teeth, but it is not clear. Failure of eruption of primary teeth may cause a number of complications, such as interference with development and eruption of succedaneous teeth, formation of cyst, and damage to adjacent teeth. This study is to report cases of primary failure of eruption in the primary dentition.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.3
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• pp.403-408
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• 2005

Ankylosis is defined as a fusion of cementum or dentine with alveolar bone. Due to the loss of the periodontal ligament on the ankylotic area, the tooth is incapable of continued eruption and hence is unable to follow the normal vertical development of the neighboring teeth and alveolar process. A 6-year-old female was referred to the Dept. of Pediatric Dentistry for ankylosis of primary molars and congenital missing of permanent premolars on both jaws. She had neither specific past medical history nor trauma and infection history in oral and maxillofacial region. Radiographic finding is that the maxillary primary molars were the early onset of ankylosis and had fast root resorption rate. However the mandibular primary molars were ankylosed later and being resorbed slower than maxillary primary molars. The object of treating this case is to maintain the proper alveolar bone growth and retention of deciduous molars. The point of managing this case is as follows: Proper treatment (observation, restoration, or extraction) should be established after thorough consideration of the time of onset, the root resorption rate, progression of infraocclusion and the development of alveolar bone support. We should consider the timing of extraction of the ankylosed teeth without problem of neighbouring alveolar bone growth and tilting of adjacent teeth in the view of growth spurt. Early diagnosis is important to avoid many of the complications with infraoccluded primary molars.

• The Journal of Korean Academy of Prosthodontics
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• v.57 no.4
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• pp.342-349
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• 2019

Purpose: The purpose of this study was to retrospectively investigate the survival and success rate of implant-supported fixed prosthesis according to the materials in the posterior area. Other purposes were to observe the complications and evaluate the factors affecting failure. Materials and methods: Patients who had been restored implant prosthesis in the posterior area by the same prosthodontist in the department of prosthodontics, dental hospital, Chonbuk National University, in the period from January 2011 to June 2018 were selected for the study. The patient's sex, age, material, location, type of prosthesis and complications were examined using medical records. The KaplanMeier method was used to analyze the survival and success rate. The Log-rank test was conducted to compare the differences between the groups. Cox proportional hazards model was used to assess the association between potential risk factors and success rate. Results: A total of 364 implants were observed in 245 patients, with an average follow-up of 17.1 months. A total of 5 implant prostheses failed and were removed, and the 3 and 5 year cumulative survival rate of all implant prostheses were 97.5 and 91.0, respectively. The 3 and 5 year cumulative success rate of all implant prostheses were 61.1% and 32.9%, respectively. Material, sex, age, location and type of prosthesis did not affect success rate (P>.05). Complications occurred in the order of proximal contact loss (53 cases), retention loss (17 cases), peri-implant mucositis (12 cases), infraocclusion (4 cases) and so on. Conclusion: Considering a high cumulative survival rate of implant-supported fixed prostheses, regardless of the materials, implant restored in posterior area can be considered as a reliable treatment to tooth replacement. However, regular inspections and, if necessary, repairs and adjustments are very important because of the frequent occurrence of complications.