This study evaluated,over a 4-month study period,the amount of apical root resorption occurring in maxillary central incisors following their retraction when employing either micro-implant or J-hook headgear anchorage...This study evaluated,over a 4-month study period,the amount of apical root resorption occurring in maxillary central incisors following their retraction when employing either micro-implant or J-hook headgear anchorage.The prospective randomised clinical trial was conducted in Orthodontic Clinic,College of Stomatology,China from 2008-2009.Subjects are patients requiring fixed appliances on waiting list (n=20).In female Han Chinese patients aged from 16-26 years,standardized periapical radiographs from 10 randomly assigned patients with maxillary protrusions comprising the micro-implant group,and from 10 similar patients comprising the J-hook headgear group,were assessed for maxillary central incisor apical root resorption.Measurements before and after orthodontic therapy were also obtained from lateral cephalometric radiographs to calculate incisor horizontal retraction and vertical intrusion distances.Estimated retraction force vectors were calculated in horizontal and vertical directions for both treatment groups.Data analysis employed t-tests and the Pearson correlation test,with α=0.05 for statistical significance.The results showed that when compared with the J-hook group,significantly more apical root resorption shortening of the maxillary central incisors was observed in the micro-implant group (1.27 mm difference,95% CI=0.70-1.84,P<0.001),which was associated with a significantly larger retraction distance (P=0.004) and a smaller vertical force component (P<0.0001).We are led to conclude that continuous activation of the nickel-titanium coil springs used in the micro-implant group resulted in significantly more apical root resorption shortening and maxillary central incisor retraction than when intermittent J-hook retraction was employed.The employment of continuous duration orthodontic forces presents a risk for increased apical root resorption that requires careful radiographic monitoring.展开更多
BACKGROUND Bimaxillary protrusion is a clinically common dentofacial deformity,particularly among Chinese patients.This kind of malformation can severely affect facial esthetics and,even in mild cases,is difficult to ...BACKGROUND Bimaxillary protrusion is a clinically common dentofacial deformity,particularly among Chinese patients.This kind of malformation can severely affect facial esthetics and,even in mild cases,is difficult to correct without surgery.Unfortunately,many patients abandon treatment because of fear of surgery.Here,we describe a case of severe skeletal bimaxillary protrusion treated with nonsurgical orthodontic treatments,highlighting an alternative treatment option.CASE SUMMARY A 31-year-old woman wished to address a severe protrusion profile(approximately 8 mm overbite)and gummy smile.Cephalometric analysis and superimposition showed a severe skeletal class II pattern with a mandibular retrusion,and proclined and protrusive mandibular incisors.Panoramic radiograph showed a missing mandibular right third molar.A diagnosis of severe bimaxillary dentoalveolar protrusion was made.Taking into account the patient’s fear of orthognathic surgery,she accepted the proposed alternative treatment using micro-implants and a self-made four-curvature torquing auxiliary.The treatment allowed for maximal en masse anterior tooth retraction,proper relocation of incisors,and alleviation of the skeletal class II pattern.Esthetically,the patient’s lip protrusion was significantly decreased as was the overjet(from 10.5 mm to 1.8 mm),and the results remained stable throughout the 2-year followup.CONCLUSION Nonsurgical treatment using micro-implants and a four-curvature torquing auxiliary may benefit severe cases of skeletal bimaxillary protrusion in adults.展开更多
Objective: combined with the clinical treatment problems of patients with orthodontic treatment, a new type of micro-implant anchorage was used in the treatment, and the application effect was analyzed. Methods: accor...Objective: combined with the clinical treatment problems of patients with orthodontic treatment, a new type of micro-implant anchorage was used in the treatment, and the application effect was analyzed. Methods: according to the requirements, suitable patients in our hospital were selected. There were 80 patients who met the standards. They received conventional treatment and micro-implant anchorage treatment respectively. The orthodontic status of the patients and the adverse reactions caused by the patient's body during the treatment in the hospital were studied. According to the clinical orthodontic indicators of the patients, the data of the two groups were compared in various aspects. Results: the orthodontic correction of the patients in the observation group achieved the expected effect after treatment. There were 39 cases without any problems, accounting for 97.50% of the population in this group, which was significantly higher than 80.00% in the control group. After effective treatment, 1 case had adverse reactions, accounting for 2.50% of the population in this group, which was not significantly less than 15.00% in the control group, and the difference was significant. After treatment, the molar displacement distance of the observation group was (3.31±0.32) mm, which was significantly smaller than that of the control group ( 5.21 ± 0.53 ) mm. ( 2.51±0.72 ) mm, the difference of incisor inclination in the observation group after treatment was ( 27.51±6.62 ) degrees, significantly larger than that in the control group ( 15.16±4.53 ) degrees, and the difference was significant (p<0.05). Conclusion: the use of micro-implant anchorage in clinical treatment of patients with orthodontic treatment has obvious advantages, which can help improve the oral deformity of patients, allow patients to have better treatment effects, and reduce the probability of adverse reactions, which is worthy of promotion.展开更多
基金supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘This study evaluated,over a 4-month study period,the amount of apical root resorption occurring in maxillary central incisors following their retraction when employing either micro-implant or J-hook headgear anchorage.The prospective randomised clinical trial was conducted in Orthodontic Clinic,College of Stomatology,China from 2008-2009.Subjects are patients requiring fixed appliances on waiting list (n=20).In female Han Chinese patients aged from 16-26 years,standardized periapical radiographs from 10 randomly assigned patients with maxillary protrusions comprising the micro-implant group,and from 10 similar patients comprising the J-hook headgear group,were assessed for maxillary central incisor apical root resorption.Measurements before and after orthodontic therapy were also obtained from lateral cephalometric radiographs to calculate incisor horizontal retraction and vertical intrusion distances.Estimated retraction force vectors were calculated in horizontal and vertical directions for both treatment groups.Data analysis employed t-tests and the Pearson correlation test,with α=0.05 for statistical significance.The results showed that when compared with the J-hook group,significantly more apical root resorption shortening of the maxillary central incisors was observed in the micro-implant group (1.27 mm difference,95% CI=0.70-1.84,P<0.001),which was associated with a significantly larger retraction distance (P=0.004) and a smaller vertical force component (P<0.0001).We are led to conclude that continuous activation of the nickel-titanium coil springs used in the micro-implant group resulted in significantly more apical root resorption shortening and maxillary central incisor retraction than when intermittent J-hook retraction was employed.The employment of continuous duration orthodontic forces presents a risk for increased apical root resorption that requires careful radiographic monitoring.
基金National Natural Science Foundation of China,No.81970906and Sichuan Science and Technology Program,No.2019YJ0689.
文摘BACKGROUND Bimaxillary protrusion is a clinically common dentofacial deformity,particularly among Chinese patients.This kind of malformation can severely affect facial esthetics and,even in mild cases,is difficult to correct without surgery.Unfortunately,many patients abandon treatment because of fear of surgery.Here,we describe a case of severe skeletal bimaxillary protrusion treated with nonsurgical orthodontic treatments,highlighting an alternative treatment option.CASE SUMMARY A 31-year-old woman wished to address a severe protrusion profile(approximately 8 mm overbite)and gummy smile.Cephalometric analysis and superimposition showed a severe skeletal class II pattern with a mandibular retrusion,and proclined and protrusive mandibular incisors.Panoramic radiograph showed a missing mandibular right third molar.A diagnosis of severe bimaxillary dentoalveolar protrusion was made.Taking into account the patient’s fear of orthognathic surgery,she accepted the proposed alternative treatment using micro-implants and a self-made four-curvature torquing auxiliary.The treatment allowed for maximal en masse anterior tooth retraction,proper relocation of incisors,and alleviation of the skeletal class II pattern.Esthetically,the patient’s lip protrusion was significantly decreased as was the overjet(from 10.5 mm to 1.8 mm),and the results remained stable throughout the 2-year followup.CONCLUSION Nonsurgical treatment using micro-implants and a four-curvature torquing auxiliary may benefit severe cases of skeletal bimaxillary protrusion in adults.
文摘Objective: combined with the clinical treatment problems of patients with orthodontic treatment, a new type of micro-implant anchorage was used in the treatment, and the application effect was analyzed. Methods: according to the requirements, suitable patients in our hospital were selected. There were 80 patients who met the standards. They received conventional treatment and micro-implant anchorage treatment respectively. The orthodontic status of the patients and the adverse reactions caused by the patient's body during the treatment in the hospital were studied. According to the clinical orthodontic indicators of the patients, the data of the two groups were compared in various aspects. Results: the orthodontic correction of the patients in the observation group achieved the expected effect after treatment. There were 39 cases without any problems, accounting for 97.50% of the population in this group, which was significantly higher than 80.00% in the control group. After effective treatment, 1 case had adverse reactions, accounting for 2.50% of the population in this group, which was not significantly less than 15.00% in the control group, and the difference was significant. After treatment, the molar displacement distance of the observation group was (3.31±0.32) mm, which was significantly smaller than that of the control group ( 5.21 ± 0.53 ) mm. ( 2.51±0.72 ) mm, the difference of incisor inclination in the observation group after treatment was ( 27.51±6.62 ) degrees, significantly larger than that in the control group ( 15.16±4.53 ) degrees, and the difference was significant (p<0.05). Conclusion: the use of micro-implant anchorage in clinical treatment of patients with orthodontic treatment has obvious advantages, which can help improve the oral deformity of patients, allow patients to have better treatment effects, and reduce the probability of adverse reactions, which is worthy of promotion.
