A Study of Success Rate of Miniscrew Implants as Temporary Anchorage Devices in Singapore

Objective. To find out the success rate of miniscrew implants in the National Dental Centre of Singapore (NDCS) and the impact of patient-related, location-related, and miniscrew implant-related factors. Materials and Methods. Two hundred and eighty-five orthodontic miniscrew implants were examined from NDCS patient records. Eleven variables were analysed to see if there is any association with success. Outcome was measured twice, immediately after surgery prior to orthodontic loading (T1) and 12 months after surgery (T2). The outcome at T2 was assessed 12 months after the miniscrew’s insertion date or after its use as a temporary anchorage device has ceased. Results. Overall success rate was 94.7% at T1 and 83.3% at T2. Multivariate analysis revealed only the length of miniscrew implant to be significantly associated with success at both T1 (P=0.002) and T2 (P=0.030). Miniscrew implants with lengths of 10–12 mm had the highest success rate (98.0%) compared to other lengths, and this is statistically significant (P=0.035). At T2, lengths of 10–12 mm had significantly (P=0.013) higher success rates (93.5%) compared to 6-7 mm (76.7%) and 8 mm (82.1%) miniscrew implants. Conclusion. Multivariate statistical analyses of 11 variables demonstrate that length of miniscrew implant is significant in determining success

A Study of Success Rate of Miniscrew Implants as Temporary Anchorage Devices in Singapore

Objective. To find out the success rate of miniscrew implants in the National Dental Centre of Singapore (NDCS) and the impact of patient-related, location-related, and miniscrew implant-related factors. Materials and Methods. Two hundred and eighty-five orthodontic miniscrew implants were examined from NDCS patient records. Eleven variables were analysed to see if there is any association with success. Outcome was measured twice, immediately after surgery prior to orthodontic loading (T1) and 12 months after surgery (T2). The outcome at T2 was assessed 12 months after the miniscrew's insertion date or after its use as a temporary anchorage device has ceased. Results. Overall success rate was 94.7% at T1 and 83.3% at T2. Multivariate analysis revealed only the length of miniscrew implant to be significantly associated with success at both T1 ( = 0.002) and T2 ( = 0.030). Miniscrew implants with lengths of 10-12 mm had the highest success rate (98.0%) compared to other lengths, and this is statistically significant ( = 0.035). At T2, lengths of 10-12 mm had significantly ( = 0.013) higher success rates (93.5%) compared to 6-7 mm (76.7%) and 8 mm (82.1%) miniscrew implants. Conclusion. Multivariate statistical analyses of 11 variables demonstrate that length of miniscrew implant is significant in determining success

Dentocacial deformities and orthognathic surgery in an Asian population

Er zijn maar weinig onderzoeksgegevens beschikbaar over het voorkomen en de behande­ling van aangezichtsafwijkingen onder de Aziatische bevolking, veroorzaakt door tandheel­kundige problemen. UMCG-promovendus Ming Tak Chew verrichtte onderzoek op dit vlak. Op basis van tandheelkundige dossiers beschreef hij onder meer de veranderende trends bij de behandeling van de afwijkingen. Ook onderzocht Chew de nauwkeurigheid van een weke delen-computersimulatie als hulpmiddel voor behandelplanning en voor­lichting van patiënten. Over het algemeen zijn de verschillen tussen de voorspelde en de feitelijke uitkomsten van behandeling klein, zo stelt Chew. Echter, omdat de mogelijkheid bestaat dat gesimuleerde afbeeldingen als esthetisch fraaier worden beoordeeld dan het daadwerkelijke resultaat, is het belangrijk dat verwachtingen van de patiënt goed begeleid worden, wanneer er gebruik wordt gemaakt van computersimulaties

Orthodontic-surgical management of an unusual dilacerated maxillary incisor

Orthodontic traction of an impacted dilacerated maxillary central incisor is clinically challenging and often results in a long treatment duration. A case of an unusual dilacerated central incisor with a 90° crown-root angulation and palatally displaced crown is presented herein. Using a single stage open window exposure of the crown on the palatal aspect with light orthodontic traction force, the impacted dilacerated central incisor crown was successfully positioned in alignment with the contralateral incisor

Effectiveness and duration of two-arch fixed appliance treatment

The aims of this study were to determine the effectiveness and duration of single-phase two-arch fixed appliance treatment and to evaluate factors that may influence these two variables. Data were collected from 177 consecutively completed cases at the Orthodontic Department, Government Dental Clinic, Singapore, during a three-month period. Pre-treatment and post-treatment models were assessed using the Peer Assessment Rating (PAR) index. The result showed that two-arch fixed appliance treatment reduced the malocclusions on average by 77.80 per cent over a period of 25 months. Multiple regression techniques revealed that 22 per cent of the variability in treatment effectiveness could be explained by the pre-treatment PAR score, the age at the start of treatment, the frequency of office visits and whether or not the treatment involved extractions. The variation in treatment duration was due to the frequency of office visits, the pre-treatment PAR score and whether or not the treatment involved extractions or headgear