下颌第三磨牙阻生伴第二磨牙牙髓病变同期治疗的临床观察

目的探讨下颌第三磨牙阻生伴第二磨牙牙髓病变同期治疗的可行性。方法对80例下颌阻生第三磨牙引起邻牙牙髓病变的患者在局麻下同期行第二磨牙的一次性根管治疗和阻生第三磨牙拔除术,根据患者反应和X线片检查评价其疗效。结果80例患者经联合治疗,成功率达91.3%。结论下颌第三磨牙阻生伴第二磨牙牙髓病变同期治疗可以缩短疗程,减轻患者痛苦。     

下颌第三磨牙阻生伴邻近第二磨牙病变临床治疗

下颌第三磨牙阻生常导致邻近第二磨牙发生病变,第二磨牙病变程度的不同决定了阻生的第三磨牙拔除与否。本文旨在对下颌第三磨牙阻生伴邻近第二磨牙病变的临床治疗方法做一综述,以期为牙体牙髓科医生的临床操作提供指导。     

下颌第二前磨牙拔除对青少年第三磨牙位置影响的观察

目的 探讨青少年正畸治疗中拔除下颌第二前磨牙对患者第三磨牙萌出位置的影响。方法 回顾性分析2007年1月—2010年1月在我门诊正畸治疗中拔除下颌第二前磨牙的55例患者的临床资料和随访资料,并以同期我院收治的未拔除下颌第二前磨牙的55例患者为对照组,比较两组患者治疗前后下颌第三磨牙位置变化情况。结果 观察组与对照组患者治疗前后第三磨牙位置均有不同程度改变,观察组主要表现为下颌第三磨牙萌出间隙增大,长轴与平面的交角变化量大。结论 拔除下颌第二前磨牙后,第三磨牙萌出间隙明显增大,有助于下颌第三磨牙的正常萌出。     

拔除病变第一磨牙后上、下颌第三磨牙正畸近移疗效比较

目的探讨拔除病变第一磨牙后上、下颌第三磨牙近移进行正畸治疗的效果。方法收集20例第一磨牙病变同时需要进行正畸治疗的患者,平均年龄18.6岁。根据患者口内情况将患者分为2组,每组10例。第一组上颌无明显拥挤,仅拔除病变的上颌第一磨牙,下颌拔牙或非拔牙矫治;第二组下颌无明显拥挤,仅拔除病变的下颌第一磨牙,上颌牙列拔牙或非拔牙治疗。全部病例均采用方丝弓矫治器,排齐整平牙列,关闭拔牙间隙,精细调整咬合关系。结果 20例患者都达到良好的矫治效果,双侧的磨牙、尖牙均达到良好的咬合关系。上颌第三磨牙前移平均8.8个月,平均近移7.94mm;下颌第三磨牙前移平均9.7个月,平均近移7.12mm。结论上、下颌由于存在骨质结构的差异,拔除无法保存的第一磨牙后,上颌第三磨牙近移比下颌磨牙较快。扶正簧的使用使倾斜的下颌磨牙得以直立。     

上颌第三磨牙对第一磨牙近中移动影响的研究

目的探讨萌出中的上颌第三磨牙是否会使上颌第一磨牙向近中移动。方法选择18～24岁正畸患者18例,均拔除4颗第一前磨牙矫治,且随机拔除一侧上颌第三磨牙,两侧其余治疗条件保持一致。治疗3个月后观察两侧上颌第一磨牙近中移动量是否存在差异。结果1)拔除上颌第三磨牙的一侧,其上颌第一磨牙在治疗3个月后未发生明显的近中移动;2)未拔除上颌第三磨牙的一侧,其上颌第一磨牙在治疗3个月后的近中移动量为1mm;3)治疗3个月后,未拔除上颌第三磨牙侧的第一磨牙近中移动量大于拔除第三磨牙侧的第一磨牙的近中移动量,其差异有统计学意义(P<0.01)。结论在正畸治疗的初始阶段,若上颌第三磨牙的萌出间隙不足,其萌出会对其近中的上颌第一磨牙产生影响,导致其近中移动而丧失支抗。     

Comparative study of the movement of upper and lower third molars after extraction of decayed first molars in orthodontics

目的 探讨拔除病变第一磨牙后上、下颌第三磨牙近移进行正畸治疗的效果.方法 收集20例第一磨牙病变同时需要进行正畸治疗的患者,平均年龄18.6岁.根据患者口内情况将患者分为2组,每组10例.第一组上颌无明显拥挤,仅拔除病变的上颌第一磨牙,下颌拔牙或非拔牙矫治;第二组下颌无明显拥挤,仅拔除病变的下颌第一磨牙,上颌牙列拔牙或非拔牙治疗.全部病例均采用方丝弓矫治器,排齐整平牙列,关闭拔牙间隙,精细调整咬合关系.结果 20例患者都达到良好的矫治效果,双侧的磨牙、尖牙均达到良好的咬合关系.上颌第三磨牙前移平均8.8个月,平均近移7.94mm;下颌第三磨牙前移平均9.7个月,平均近移7.12mm.结论 上、下颌由于存在骨质结构的差异,拔除无法保存的第一磨牙后,上颌第三磨牙近移比下颌磨牙较快.扶正簧的使用使倾斜的下颌磨牙得以直立.     

正畸拔除第一前磨牙对第三磨牙萌出角度的影响

目的：研究正畸拔除第一前磨牙对第三磨牙的影响。方法：37例第一前磨牙拔除和33例非拔牙患者作为研究对象,拍摄术前术后的全景片,测量第三磨牙长轴与平面及第三磨牙长轴与第二磨牙长轴的夹角,对治疗前后夹角的变化以U检验进行比较。结果：结果显示,拔除第一前磨牙后,下颌第三磨牙的的萌出角度得到了改善,而对上颌第三磨牙萌出改善并不明显。结论：拔除下颌第一前磨牙后,第三磨牙萌出角度会更加直立,从而可能减少其阻生的可能性。     

正畸治疗中磨牙的拔除和保留(十一)——拔除第二磨牙与拔除第一前磨牙后第三磨牙牙胚位置的对比研究

目的：比较正畸治疗中拔除第二磨牙与拔除第一前磨牙后第三磨牙牙胚位置的不同改变。方法：选择拔除第二磨牙患者18例及拔除第一前磨牙患者20例,对两组治疗前后X线头颅侧位片进行测量分析。观察矫治前后第三磨牙在垂直方向、水平方向及倾斜角度的改变,比较两组间的差异。结果：两组病例上、下颌第三磨牙垂直位置的改变有显著性差异,拔除第二磨牙组比拔除第一前磨牙组第三磨牙向胎方移动快。水平距离的改变两组之间无差异。拔除第二磨牙组的下颌第三磨牙在矫治后明显竖直,与对照组之间存在显著性差异;矫治后两组上颌第三磨牙的角度均有较大改善,但两组之间的改变无差异。结论：拔除第二磨牙比拔除第一前磨牙加速了第三磨牙向骀方的移动,有利于下颌第三磨牙的竖直,为其以后的萌出创造了有利条件,减少了第三磨牙阻生的可能性。     

下颌第三磨牙拔除与下颌第二磨牙同期治疗57例

<正> 下颌第三磨牙阻生在临床上引起诸多并发症,因邻牙远中龋或牙髓根尖病变而拔除的占20％以上。我科从1998年至今应用高速涡轮机辅助拔除第三磨牙,并同期治疗邻牙57例,效果良好,现报告如下。l 资料和方法 选取门诊下颌第三磨牙阻生致邻牙远中龋或牙髓根尖周病变者57例,男31例,女26例,均为单侧。患者年龄ZI-43岁,平均31.5岁。近中阻生占87％,水平阻生占13％。     

第三磨牙拔除后的下颌骨骨折

资料来自1995～1998年期间治疗的下颌骨骨折病例,从中选择因拔除下须第三磨牙而发生骨折的患者,评价其病史,物理检查所见,X线发现和治疗过程。共手术拔除917例下颌第三磨牙,有6例发生下颌骨骨折,其中5例男性,1例女性,平均年龄45岁(42～50岁)。资料显示,6例中有1例同时拔除下颌第二、三磨牙,其余均只拔1颗第三磨牙。拔牙前1例存在滤泡囊肿,2例相邻的第二磨牙有     

The wisdom behind third molar extractions

The literature pertaining to the extraction of third molars is extensive. There is a large individual variation and a multitude of practitioners’ beliefs and biases relating to the extraction of especially asymptomatic and pathology free third molars. With the current emphasis in dentistry being placed on clinicians to make evidence‐based decisions, the routine removal of third molars has been re‐assessed and questioned. The purpose of this paper was to evaluate past and present knowledge of third molar extractions and relate it to logical considerations relevant to science and the evidence‐based decision‐making process. This paper endeavours to encourage and stimulate clinicians to re‐evaluate their views on third molar extractions based on suggested guidelines and current evidence.     

General dental practitioners'' evaluation of the need for extraction of asymptomatic mandibular third molars

Thirty general dental practitioners were asked to evaluate the need for extraction of asymptomatic mandibular third molars. Thirty-six mandibular third molars with equal distribution of angular positions, impaction status, males and females and age groups were selected. To estimate the consistency of the evaluation, the 36 cases were duplicated so that, in all, 72 teeth were evaluated. The number of molars proposed to be extracted by the observers varied from 0 to 26. There was no third molar which all observers agreed should be extracted. The two molars which most observers, 25 and 23 of altogether 30 observers, proposed to be extracted were partially covered by soft tissue. The decision not to extract two molars was unanimous. Both of these were completely covered by bone tissue and positioned vertically. The mean overall intra-observer agreement for the therapeutical decision was 92%, with a range of 69-100%. The length of professional experience of the observer did not influence the evaluation whether or not to extract. We conclude that there is a great variation among general dental practitioners regarding their evaluation on the need for removal of asymptomatic mandibular third molars.     

General technique of third molar removal

The most commonly performed surgical procedure in most oral and maxillofacial surgery practices is the removal of impacted third molars. Extensive training, skill, and experience allow this procedure to be performed in an atraumatic fashion with local anesthesia, sedation, or general anesthesia. The decision to remove symptomatic third molars is not usually difficult, but the decision to remove asymptomatic third molars is sometimes less clear and requires clinical experience. A wide body of literature (discussed elsewhere in this issue) attempts to establish clinical practice guidelines for dealing with impacted teeth. Data is beginning to accumulate from third molar studies, which hopefully will provide surgeons and their patients with evidence-based guidelines regarding elective third molar surgery.     

Characteristics of disease related to mesio-angular mandibular third molar teeth

The aim of this study was to identify the indications for the removal of mesio-angular mandibular third molars based on age and dental health as measured by the DMFT (decayed, missing, and filled teeth) score, and to find out if early intervention should be considered. We studied 319 patients who had 431 mesio-angular mandibular third molars removed. Variables recorded were age, primary indication for removal, and the DMFT score. Indications for removal included distal cervical caries (DCC) in the mandibular second molar (n = 180, 44%), pericoronitis (n = 131, 32%), and caries and related disease (n = 62, 15%). The frequency of distal cervical caries (DCC) in the mandibular second molar increased linearly as patients became older and was the most common reason why mesio-angular third molar teeth were removed. This suggests that patients should be advised of the consequences of retaining thesetypes of third molars, and offered prophylactic removal of asymptomatic teeth.     

Incidence of occlusal dental caries in asymptomatic third molars.

PURPOSE: We sought to determine the incidence of caries experience on the occlusal surface of asymptomatic third molars erupted to the occlusal plane and to examine the association between the prevalence of caries experience in third molars and other molars. PATIENTS AND METHODS: Clinical data were collected from healthy patients (ASA Class I, II) with asymptomatic third molars enrolled at 2 clinical centers in an institutional review board-approved clinical trial. All patients with at least one third molar at the occlusal plane and with data at baseline and from the most recent of at least 2 follow-up visits were compared in the analysis. At each visit, the presence or absence of caries experience on the occlusal surface of third molars and on any surface of the first and second molars was recorded during clinical and radiographic examinations. RESULTS: Median time between baseline and the most recent follow-up examination was 2.9 years (interquartile range, 1.6 to 4.0 years). Patients (N = 211) were more often female (55%) and white (79%). Median age at baseline was 26.6 years (interquartile range, 22.7 to 32.6 years). At baseline, 29% of patients were affected by third molar occlusal caries, increasing to 33% at follow-up. Older patients at baseline had more caries in a third molar than those younger than 25 years (43% versus 9%). However, patients who were younger at baseline were more likely to develop caries in third molars at follow-up (9% versus 19%). Mandibular third molars were affected more often than maxillary third molars: 25% versus 19% at baseline and 29% versus 22% at follow-up. At baseline and at follow-up, nearly all patients with third molar caries, 98% and 99%, also had caries in first/second molars. CONCLUSIONS: The 3-year caries incidence in third molars erupted to the occlusal plane was highest among younger patients and mandibular teeth. The presence of caries in first/second molars at baseline was highly predictive of the development of third molar caries during the ensuing 3 years.     

The unerupted or impacted third molar--a critical appraisal of its pathologic potential

The prophylactic removal of asymptomatic unerupted or impacted third molars constitutes a major proportion of all oral surgical procedures. Patients are advised to have this preventive surgery on the basis that such teeth, if retained, are likely to cause certain pathologic lesions. The evidence in the scientific literature on the prevalence of dentigerous cysts, mural ameloblastoma, epidermoid carcinoma and root resorption indicates that this concern is exaggerated. The retrospective data on the reasons for extractions of third molars confirm this conclusion. Until there are prospective studies which demonstrate a significant patient benefit from surgery exceeding the risks of retention, the practice should be discontinued. Third molars should be removed only where there is a defined pathologic indication.     

New considerations in the treatment of compromised third molars

Management of asymptomatic malposed third molars is a controversial topic. As a result, many malposed or mildly pathologic third molars are not removed. Historical pro and con arguments regarding removal centered around cost and the aspects of the surgical removal itself. Current epidemiology and medical advances address issues not considered before. There is a large growth of the aging population (over 40 years). More and more of these elderly patients are requiring third molar removal. Over a five-year period, 1997-2002, the incidence almost doubled to 17.9 percent. This age category is known to be high risk for third molar surgery. An equally or higher risk is the rapidly growing number of patients seeking third molar surgery who are moderately severely medically compromised. This paper reviews how this lack of consensus results in delayed removal of malposed third molars in this population. Preventive dental concepts, removing compromised third molars earlier, would eliminate the high risk to this aging population.     

Dentists' decisions on prophylactic removal of mandibular third molars: a 10-year follow-up study

OBJECTIVES: In recent years, several critical outcome studies concerning the prophylactic removal of mandibular third molars have been published. These would appear to motivate a more restrictive approach today as compared with 10 years ago. The aim of the present study was to examine dentists' decisions on the prophylactic removal of impacted mandibular third molars over a 10-year period. METHODS: Thirty-six cases were selected so as to represent an equal distribution of males and females, ages, angular position and degree of impaction of the molar. Twenty-six general dental practitioners (GDPs) and 10 oral surgeons judged the same cases on two occasions 10 years apart. RESULTS: Calculated for each category of dentists, there was no significant difference in the mean number of molars designated for removal between the two occasions. Two GDPs and three oral surgeons presented a higher removal rate, whereas five GDPs presented a lower removal rate on the second occasion as compared to the first one. The dentists presented a considerable interindividual variation in removal rate, between 0 and 22 molars on the first occasion and between 0 and 25 molars on the second occasion. CONCLUSION: In the decisions on prophylactic removal of mandibular third molars, there has been no change over the last 10 years towards a more noninterventionist attitude. Thus, the dentists seem not to have been influenced by the evidence that this intervention is not cost-effective.     

Effect of selected literature on dentists' decisions to remove asymptomatic, impacted lower third molars

The aim of this study was to assess the effect of studying selected literature on dentists' decisions to remove asymptomatic, impacted lower third molars. A pre-test-post-test control group design was used. Given 36 patient cases, two groups of 16 general dental practitioners each were asked to assess the need for removal of asymptomatic impacted lower third molars. The cases were classified by three parameters: 'position of the third molar', 'impaction type', and 'patient age'. After studying selected literature on this subject by the intervention group, both groups were asked to assess the same cases again. Frequencies of decisions to remove the third molars were calculated. For each participant, tables were composed by crosstabulating the indication to remove a third molar with each of the three parameters. T-tests were used to test the significance of the difference between pre-test and post-test decisions. The overall number of indications to remove asymptomatic, impacted lower third molars decreased by 37% in the intervention group. In the control group, the difference between pre- and post-test was not statistically significant. It was concluded that the provision of selected literature significantly influences treatment decision making by dentists in a third molar decision task.