Accuracy of computer-assisted orthognathic surgery

Introduction

The purpose of this study was to retrospectively evaluate the difference between the planned and the actual movements of the jaws, using three-dimensional (3D) software for PC-assisted orthognathic surgery, to establish the accuracy of the procedure.

Satisfaction with orthodontic treatment outcome

Objectives:To examine factors associated with treatment outcome satisfaction in a group of adolescent patients.Materials and Methods:One hundred and twenty patients (60 girls and 60 boys; mean age, 14.3 years; standard deviation [SD], 1.73 years) were consecutively recruited. The inclusion criteria for all patients were as follows: adolescents with a permanent dentition in need of orthodontic treatment and a treatment plan involving extractions (two or four premolars) followed by fixed appliances in both jaws. Questionnaire 1, concerning treatment motivation and expectations, was assessed prior to treatment start. Questionnaire 2 was assessed after active treatment and included questions about satisfaction with treatment outcome, quality of care and attention, and perceived pain and discomfort during active treatment.Results:One hundred and ten patients completed the trial (54 boys and 56 girls; mean age, 16.9 years; SD, 1.78 years). Median values for satisfaction with treatment outcome were generally high. There was a clear correlation (P ≤ .001) between satisfaction with treatment outcome and patients'' perception of how well they had been informed and cared for during treatment. Pain and discomfort during treatment also strongly affected treatment satisfaction. Sex, treatment time, and Peer Assessment Rating index pre- and posttreatment as well as expectations for future treatment showed no correlation with treatment satisfaction.Conclusions:Care and attention was the variable showing the highest correlation with satisfaction with treatment outcome. Patients'' perceptions of pain and discomfort during treatment had an overall negative correlation with treatment satisfaction. Satisfaction with treatment outcome is a complex issue and requires further exploration in future research.     

Multipurpose use of orthodontic mini-implants to achieve different treatment goals

Objectives

The goal of the study was to determine whether mini-implants inserted in the palate can be used to achieve more than one treatment goal consecutively or simultaneously in the same patient.

Materials and methods

The treatment results of 43?patients were retrospectively assessed. Two implant-supported mechanical systems per patient were applied either consecutively in 19 patients (group?A) or simultaneously in 24?patients (group?B). Both groups were analyzed and compared by calculating success rates for achievement of the treatment goals, survival of the mini-implants, and quality of anchorage. Durations of treatment were also analyzed for intergroup differences.

Results

Except for a single case in group A, the treatment goals were achieved in all patients (success rates 94.7% in group?A versus 100% in group?B). Anchorage loss was confined to one patient per group (success rates 94.7% in group?A and 95.3% in group?B). Mini-implant mobility, and hence implant failure, was observed in three implants in group?A (survival rate 91.8%) and two implants in group?B (survival rate 95.6%). While none of these intergroup differences were statistically significant, the treatment durations in both groups differed widely: those in group?B were significantly shorter (10.0?±?4.2?months) than those in group?A (14.4?±?3.5?months; p?=?0.001).

Conclusion

Mini-implants inserted in the palate for skeletal anchorage can be used to achieve more than one treatment goal in the same patient. Such multipurpose application can succeed consecutively and simultaneously. The latter option can significantly expedite treatments and should, therefore, be preferred when feasible, depending on the nature of coexisting therapeutic indications in a given patient.     

Occlusal outcomes in combined orthodontic and orthognathic treatment

Objective: To investigate the treatment outcome in terms of the malocclusion features and the changes in the occlusion of patients undergoing orthodontic/orthognathic treatment using the Peer Assessment Rating (PAR) and the Index of Complexity, Outcome and Need (ICON) and to test the application of the Index of Orthognathic Functional Treatment Need (IOFTN) on this sample as a measure of orthognathic pre-treatment need.

Design: Retrospective longitudinal cohort study.

Setting: The orthodontic department at the Eastman Dental Hospital.

Material and methods: The study models of a sample of 100 orthodontic/orthognathic patients who were treated at the Eastman Dental Hospital were measured using the PAR index and ICON at three stages: pre-treatment, pre-surgery and at debond. Treatment need was assessed by measuring IOTN and IOFTN using start study models.

Results: 99% of the sample showed an improvement in PAR score, with 82% of the sample being greatly improved. ICON showed that 95% of the sample had an improvement of different degrees with 5% being not improved or worse. The IOFTN qualified 97% of the patients for orthognathic treatment when used retrospectively on the sample while the DHC of IOTN qualified the whole sample for orthodontic treatment.

Conclusions: Orthodontic/orthognathic treatment showed improved and acceptable overall results. The PAR index and ICON were valid measures to investigate the outcome of orthognathic treatment. IOFTN proved to be a useful tool in determining and prioritizing orthognathic treatment based purely on functional need.     

36例下切牙先天缺失正畸治疗的临床体会

目的探讨下切牙先天缺失的矫治设计。方法以伴有下切牙先天缺失的36例错畸形患者为研究对象,对下切牙缺失的部位、数目、错类型、矫治方法进行分析,并对缺失1颗下中切牙、拔除上颌2颗第一前磨牙和下颌1颗非缺牙侧第一前磨牙的病例及缺失2颗下中切牙、拔除上颌2颗第一前磨牙的病例的Bolton指数分析进行统计学检验。结果36例患者正畸治疗后均取得了较好的疗效。两组拔牙病例之间的Bolton指数全牙比无统计学差异（P>0.05）,而前牙比和前牙不调量有统计学差异（P<0.01）。结论先天缺1颗下中切牙上下颌均需拔牙者,在下颌非缺牙侧选择拔1颗前磨牙比拔1颗中切牙对Bolton指数影响要小     

计算机辅助导航在复杂颧骨颧弓骨折治疗中的教学应用

复杂颧骨颧弓骨折是颌面部骨折的教学难点,将计算机辅助导航应用于复杂颧骨颧弓骨折的教学过程,使其成为理论与实践相互转化的桥梁,极大提高学生主动参与的积极性,提升学习效率。该技术在教学实践中的应用,是对传统教学模式的完善及革新,值得在口腔颌面外科教学过程中推广。     

Relationship between pre-treatment orthodontic case complexities and their treatment outcomes

PurposeTo determine whether pre-treatment orthodontic case complexities were associated with their treatment outcomes in each category of malocclusion.Materials and methodsTwo hundred orthodontic cases treated with edgewise appliances from university clinic that satisfied requirements for the certification were studied. The Discrepancy Index (DI) and the Objective Grading System (OGS) were calculated. The relationship between these measurements was evaluated using Pearson’s correlation coefficient.ResultsThe mean DI score was 23.67 ± 10.30, and the mean OGS score was 19.92 ± 6.92. Statistically, there was only a weak and insignificant correlation between the DI and OGS (r = 0.055, p > 0.05). Buccolingual inclinations and interproximal contacts were components that had the highest and lowest mean OGS scores respectively.ConclusionMalocclusion complexity was not associated with orthodontic treatment outcomes. Cases which underwent two-phase treatment were found to have the most complex pre-treatment malocclusion and also the most unsatisfactory clinical outcomes. The OGS component with the highest discrepancies was buccolingual inclinations.     

Prevalence of white spot lesion formation during orthodontic treatment

Purpose:To quantify the prevalence of white spot lesions (WSLs) on the anterior teeth and, secondarily, to evaluate risk factors and predictors.Materials and Methods:Digital photographs and records of 885 randomly chosen patients were evaluated before and after treatment. Chart information included gender, age, as well as banding and debanding dates. Fluorosis and oral hygiene before and after treatment were also evaluated. Preexisting and posttreatment WSLs were recorded and compared for all 12 anterior teeth. Risk ratios (RR) and absolute risk (AR) were calculated to determine the likelihood and risk of WSL formation.Results:Overall, 23.4% of the patients developed at least one WSL during their course of treatment. Maxillary anterior teeth were affected more than mandibular teeth. The maxillary laterals and canines and the mandibular canines were the most susceptible. There was no significant difference in WSLs between genders. Fluorosis, treatment time in excess of 36 months, poor pretreatment hygiene, hygiene changes during treatment, and preexisting WSLs were all significantly (P < .05) related to the development of WSLs. The highest risk of developing WSLs was associated with preexisting WSLs (RR = 3.40), followed by declines in oral hygiene during treatment (RR = 3.12) and poor pretreatment oral hygiene (RR = 2.83).Conclusions:Nearly 25% of the patients developed WSLs while in treatment, depending on fluorosis, treatment time, preexisting WSLs, and oral hygiene. Orthodontists need to be mindful of these risk factors when making treatment decisions.     

Evaluation of accuracy and sensory outcomes of mandibular reconstruction using computer-assisted surgical simulation

Purpose

To introduce a modified protocol for mandibular reconstruction and evaluate the protocol using a standardized assessment method.

正畸治疗疼痛的研究进展

疼痛是正畸治疗中最常见的问题之一,随着患者对治疗舒适度要求的增加,如何认识正畸治疗中的疼痛特点,如何减轻正畸治疗的疼痛程度,成为正畸医师关注的研究热点.本文就正畸治疗时疼痛的特点和减轻疼痛方法的研究进展作一综述.     

正畸疼痛的临床研究

疼痛是正畸牙移动过程中的最常见症状之一。许多研究表明疼痛已经成为患者中断正畸治疗最主要的原因之一,随着患者对治疗舒适度要求的增加,如何监测正畸疼痛,如何减轻正畸治疗过程中的疼痛成为正畸医生的研究热点。本文就正畸过程中产生的疼痛特点以及临床上正畸疼痛的控制方法以及研究进展做一综述。     

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目的探讨微钛板支抗对正畸治疗的有效性。方法选择2003年12月至2006年11月期间,大连市口腔医院应用微钛板矫治的12例患者,分析其治疗前后头颅侧位片、模型等临床资料,评价微钛板对牙齿移动特征及正畸疗效的影响。结果12例正畸矫治患者均取得了满意的治疗效果,12例患者使用的23枚微钛板均由同一外科医生埋入,每个微钛板埋入时间需10min左右。微钛板作为绝对支抗的应用时间为9～20个月。治疗中23枚微钛板均稳定,无脱落。其中9例患者利用微钛板在远、近中方向上调整牙齿位置,其移动方式以整体移动为主,上下颌磨牙远中移动最多可达3.5mm。结论微钛板作为一种绝对支抗,实现了传统正畸手段在牙齿近远中移动、压低方面难以完成的牙齿移动类型,有效地获得了传统正畸方法难以达到的临床效果。     

医源性牙位、肌位不调再正畸治疗的疗效评价

目的：探讨正畸治疗引起的牙位、肌位不调，并评价其后续正畸治疗疗效。方法：采用直丝弓矫治器配合复合头帽口外牵引装置，对19例医源性牙位、肌位不调患者进行矫治，对治疗前后X线头颅定位侧位片进行对比分析。结果：在正畸临床工作中，医生不当的设计、治疗和患者较差的配合，可导致医源性牙位、肌位不调；用口内直丝弓矫治器与复合头帽口外牵引装置联合治疗，可明显推上牙弓向后；磨牙整体后移达到安氏Ⅰ类关系，恢复牙位、肌位良好的协调关系。结论：口腔正畸医生对医源性牙位、肌位不调应引起足够的重视；口内直丝弓矫治器配合复合头帽口外牵引装置对牙尖交错殆前错位患者的疗效确切。     

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口腔影像学是口腔正畸学诊断的重要依据。锥形束CT（CBCT）的临床应用使正畸诊断从二维时代走向了三维时代。CBCT对于正畸治疗方案设计、治疗后的预测以及治疗效果的评价等具有重要的作用。     

青少年产生正畸治疗需求动机的影响因素

目的：研究各种主、客观因素对青少年产生正畸治疗需求动机的影响。方法：随机抽取１１岁～１３岁青少年３００名（男女各半），做问卷调查，测量研究模型，获得被测试的治疗优先指数（ｔｒｅａｔｍｅｎｔｐｒｉｏｒｉｔｙｉｎｄｅｘ，ＴＰＩ）等级。结果：１．青少年的认知水平和对外界反馈的认知均与治疗需求显著相关；２．性别因素、家长因素及客观畸形程度都对治疗需求产生影响。结论：青少年正畸治疗需求动机的产生受社会心理因素及客观畸形程度的影响     

Consistency of orthodontic treatment planning decisions

The aim of this project was to analyse the consistency of a group of orthodontists’ treatment decisions and to identify factors that may influence this consistency. Ten orthodontists examined 60 case vignettes and recorded their treatment decisions on two separate occasions. Inter- and intra-examiner agreements were measured using the Kappa statistic. Data analysis revealed that the consistency within each orthodontist was moderate. However, between-orthodontist consistency was poor. It can be concluded that there is marked variation between orthodontists in treatment planning decisions, and this may reflect the lack of evidence for the effectiveness of competing treatments.