The implant prosthesis can be divided into the screw retained prosthesis and cement retained prosthesis. Each type has advantages as well as disadvantages which is unfavorable to maintain the implants. To overcome these drawbacks, T-screw system was developed. T-screw system which utilizes a lingual direction of the screw to retain the implant prosthesis, has advantages of retrievability of the prosthesis, passive fit, and possibility to form esthetic and functional occlusal surface. The prior prosthesis which utilized horizontal screws had difficulty in fabrication especially in the case of multiple units, and also limited use with all-ceramic prosthesis. In this case, fabricating the implant prosthesis by using the T-screw system showed superior results in easy maintenance, esthetics, and also functions. In addition, we are to report the method of using the T-screw system in implant prosthesis, such as multiple units of implant prosthesis and all ceramic prosthesis.
Ceramics ; Dental Implants ; Dental Prosthesis* ; Dental Prosthesis, Implant-Supported ; Dental Restoration Failure ; Dental Restoration Repair ; Esthetics ; Methods ; Peri-Implantitis ; Prostheses and Implants

OBJECTIVE: To retrospectively figure out the oral health status, treatment and follow-ups after dental treatment under general anesthesia (DGA) of disabled children or adolescents. METHODS: Clinical data of disabled children or adolescents and normal children as control received DGA in the Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology from August 2008 to September 2015 were recorded, including: gender, birth date, treatment date, disability type, oral health status before treatment, treatment content and follow-ups (in 1 year). Differences among ages and disabilities were analyzed statistically. RESULTS: Sixty-two disabled patients and fifty-seven controls were recruited, mean aged (9.38±5.22) years and (3.00±1.41) years. Most patients had 10 to 15 problem teeth with which the mean number of the disabled children and adolescents was (11.79±4.98) while that of the normal controls was (12.40±4.11). Caries, pulpitis, periapical periodontitis, dental trauma and developmental tooth anomalies of the disabled patients accounted for 67.56%, 13.54%, 15.15%, 1.07%, and 2.68%, respectively and the DMFT/dmft index was 11.55±5.56 while in the control group those were at 65.35%,19.09%,14.14%,0,1.41% and 12.23±4.42. The DMFT/dmft index of the disabled patients in the group 6-12 years (8.35±4.69) was significantly less than that of the other three groups (P<0.01) while no differences were found in disabilities (P=0.239). Resin restoration, pit and fissure sealant, preventive resin restoration, pulpotomy, pulpectomy/RCT, extraction and crown of the disabled patients were performed as 52.71%, 7.24%, 8.56%, 0.72%, 17.13%, 10.01% and 3.62% respectively whereas those made up as 56.31%, 1.27%, 0.13%, 2.29%, 19.87%, 7.90% and 12.23% in the control group. Thirty-five (56.45%) disabled patients and forty-three (75.44%) controls recalled. Problem teeth within one year after operation in diabled patients and controls were both nearly twice as much as the number within half a year. Restoration loss/fractured mainly occurred in anterior primary teeth while secondary/ recurrent caries and pulpitis/perapical periodontitis mostly occurred in primary molars. CONCLUSION Oral health status in our disabled children and adolescents is poor. Though dental treatment under GA is an effective way to improve the oral health of disabled children and adolescents, periodic follow-ups and family oral health care are equal important for oral health maintenance.
Adolescent ; Anesthesia, Dental ; Anesthesia, General ; Child ; Child, Preschool ; Dental Care ; Dental Caries ; Dental Restoration Repair/methods* ; Disabled Children ; Female ; Humans ; Male ; Molar ; Pediatric Dentistry ; Pit and Fissure Sealants ; Pulpitis ; Retrospective Studies ; Tooth, Deciduous