The applications of stereolithography in facial reconstructive surgery

The development of rapid prototyping has evolved from the crude milled models to the laser polymerised stereolithographic models of excellent accuracy. The technology was advanced further with the recent introduction of fused deposition modelling and the 3-dimensional ink-jet printing technique in stereo-model fabrication. The concept of using a 3-dimensional model in planning the operation has amazed the maxillofacial surgeons since its first application in grafting a skull defect in 1995. It was followed by many bright ideas of applications in the field of facial reconstructive surgery. The stereo-model may assist in the diagnosis of facial fractures, joint ankylosis and even impacted teeth. The surgery can be simulated prior to the operation of complex craniofacial syndromes, facial asymmetry and distraction osteogenesis. The stereo-model can be used for preparation of reconstructive plate or joint prosthesis. It has an enormous value as an educational teaching and patient information tool for obtaining the consent for surgery. The aims of the paper are to present the modern manufacturing methods of the stereo-model and to illustrate the clinical applications of the stereomodel in facial reconstruction.published_or_final_versio

Factors determining Hong Kong adults' satisfaction with dental care

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Periodontal conditions in adult Southern Chinese

Periodontal diseases remain a concern in adult populations, but there have been no systematic descriptions of periodontal conditions, which have included periodontal attachment loss, among Southern Chinese. The main aim of this report is to describe the periodontal conditions in adult Chinese and to investigate factors that may have influenced periodontal attachment loss. Subjects were recruited from urban and rural survey sites throughout Guangdong. In total, 1572 35- to 44-year-old subjects and 1286 65- to 74-year-old subjects completed a structured interview and underwent a periodontal examination, which included the Community Periodontal Index (CPI) and periodontal Attachment Loss (ALoss) recordings. Calculus was found as the highest CPI score in 61-68% of the 35- to 44-year-old subjects and in 54-57% of the 65- to 74-year-olds. Shallow pockets were found as the highest CPI score in about one-third of both the urban and the rural subjects in both age groups, and deep pockets in 3-7% of the subjects. ALoss was more prevalent than pockets in both age groups. On the basis of the ALoss recordings, about one-third of the subjects in both age groups were categorized as exhibiting considerable ALoss for their age. In both age groups, logistic regression analysis indicated that being male, wearing partial dentures, and reporting less frequent toothbrushing were found to be associated with considerable ALoss.published_or_final_versio

Long-term outcome of primary non-surgical root canal treatment

Aim: The aim of this study is to examine the survival distributions of primary root canal treatment using interval-censored data and to assess the factors affecting the outcome of primary root canal treatment, in terms of periapical healing and tooth survival. Materials and methods: About one tenth of primary root canal treatment performed between January 1981 and December 1994 in a dental teaching hospital were systematically sampled for inclusion in this study. Information about the patients' personal particulars, medical history, pre-operative status, treatment details, and previous review status of the treated teeth, were obtained from dental records. Patients were recalled for examination clinically and radiographically. Treatment outcomes were categorized according to the status for periapical healing and tooth survival. The event time was interval-censored and subjected to survival analysis using the Weibull accelerated failure time model. Results: A total of 889 teeth were suitable for analysis. Survival curves of both outcome measures (periapical healing and tooth survival) declined in a non-linear fashion with time. Median survival of the treated teeth was 119 months (periapical healing) and 252 months (tooth survival). Age, tooth type, pre-operative periapical status, occlusion, type of final restoration, and condition of the tooth/restoration margin were significant factors affecting both periapical healing and tooth survival. Apical extent and homogeneity of root canal fillings had a significant impact towards periapical healing (p < 0.05), but not tooth survival. Conclusion: The longevity of treated teeth based on tooth survival was considerably greater than that of periapical healing. Both outcome measures were affected by a number of socio-demographic, pre-, intra-, and post-operative factors. Clinical relevance: Root canal-treated teeth may continue to function for a considerable period of time even though there may be radiographic periapical lesion present. Decision for extraction may be due to reasons other than a failure of the periapical tissues to heal. © 2011 The Author(s).published_or_final_versionSpringer Open Choice, 28 May 201

Translation and validation of the Chinese (HK) version of GOHAI

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Prevention of early childhood caries - a fluoride toothpaste demonstration trial on Chinese children

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Patterns of dental caries severity in Chinese kindergarten children

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Translation and validation of the Chinese (HK) version of OHIP

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Two-year result of a field trial on prevention of oral disease in Chinese kindergarten children

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Arresting rampant caries through daily brushing with fluoride toothpaste in Chinese kindergarten children

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