减数磨牙矫治设计中第三磨牙相关问题的考量

正畸治疗时常会选择拔除无法保留或保留预后较差的第一或第二磨牙,或者主动减数健康的磨牙以利于纠正颌骨不调的问题.此时第三磨牙的牙根发育状况,能否顺利萌出并成功代替第二磨牙行使功能,以及如何正畸牵引阻生的第三磨牙,均是正畸治疗的难点.本文就减数磨牙矫治设计中影响第三磨牙发育及萌出的相关因素作一综述.     

Efficacy of platelet rich plasma in bone regeneration after surgical removal of impacted bilateral mandibular third molars: pilot study

Purpose  

This study was done to assess the efficacy of platelet rich plasma (PRP) in bone regeneration.     

Comparative evaluation of surgical outcome after removal of impacted mandibular third molars using a Piezotome or a conventional handpiece: a prospective study

Our aim was to compare the use of a conventional rotary handpiece and a Piezosurgical unit for extraction of lower third molars. We studied 40 patients, who were allocated alternately to have the third molar removed with either the handpiece or the Piezosurgical unit. Pain, trismus, and oedema were evaluated at baseline and then postoperatively, together with paraesthesiae, on postoperative days 1, 3, 5, 7, and 15. Damage to surrounding tissue was checked on the same day whereas dry socket was evaluated from postoperative day 3 onwards. More patients complained of pain in the conventional group, they also required more analgesics, and they developed trismus more often than in the Piezosurgery group. There was also significantly more postoperative swelling in the conventional group. Patients were also evaluated using the subjective Postoperative Symptom Severity (PoSSe) scale. Our results suggest that apart from some inherent limitations with the Piezotome, it is a valuable alternative for extraction of third molars.     

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。     

The effect of sutureless wound closure on postoperative pain and swelling after impacted mandibular third molar surgery

Our aim was to assess the influence of sutureless and multiple-suture closure of wounds on postoperative complications after extraction of bilateral, impacted, mandibular third molars in 30 patients in a split mouth study. After the teeth had been removed, on one side the flap was replaced but with no suture to hold it in place (study side), and on the other side the wound was closed primarily with three sutures (control side). Recorded complications included pain, swelling, bleeding, and formation of periodontal pockets. The results showed that patients had significantly less postoperative pain and swelling when no sutures were used (p=0.005). There were no signs of excessive bleeding or oozing postoperatively on either side. Six months postoperatively there was no significant difference in the depth of the periodontal pocket around the second molar.     

末端磨牙区拥挤与下颌智齿牙根形态的关系

目的探讨磨牙区拥挤与下颌智齿牙根发育形态之间的关系。方法选择下颌第三磨牙牙根发育完成的22-35岁成年正畸患者的曲面断层片1056张,观察下颌第一、第二及第三磨牙牙根分叉和聚拢的分布情况,探讨下颌第三磨牙阻生与完全萌出与其牙根聚拢程度的关系。结果从下颌第一磨牙至第三磨牙,牙根聚拢程度有增加的趋势。下颌第三磨牙阻生与否对于牙根的分开与聚拢没有显著影响。结论下颌第三磨牙牙根形态变异较大,牙根的分开与聚拢与末端磨牙区拥挤与否无明显关联。     

A regimen of systematic periodontal care after removal of impacted mandibular third molars manages periodontal pockets associated with the mandibular second molars

AIM: This randomized, single-blinded control trial investigated the local effects of periodontal care on the mandibular second molar delivered during and after impacted third molar surgical extraction. METHOD: Thirty subjects (50% male, 32.1+/-7.8 years) out of 35 enrolled, with a mesio-angular impacted mandibular third molar, having probing pocket depth (PPD) >5 mm at adjacent second molar distal, and crestal radio-lucency between the two teeth, completed the study. Oral hygiene instruction, scaling and caries stabilization were performed before surgery. Controls (n=16) had their third molar extracted followed by standard socket debridement. Test group subjects (n=14) received the same treatment, except that before wound closure the operator was informed of the group allocation and ultrasonic root debridement on the second molar was performed, followed by a three-visit plaque control programme. RESULTS: Six months post-extraction, statistically significantly (p<0.007) better plaque control and shallower probing depths were observed at test second molars' distal (%plaque=21; PPD=3.2+/-1.2 mm) than at control second molars (%plaque=88; PPD=5.2+/-0.7 mm). CONCLUSIONS: The periodontal interventions investigated prevented residual pockets on periodontally involved second molars 6 months after ipsilateral impacted mandibular third molar removal.     

Intraoperative removal of third molars does not affect the postoperative infections after BSSO - Randomized controlled trial

The goal of this study was to evaluate the incidence of postoperative wound infection and timing of mandibular third molar removal in bilateral sagittal split osteotomy (BSSO).This wis a prospective, single-blinded, randomized, split-mouth clinical trial. All patients were divided into two groups: Group I, where pre-operative removal of the third molars were done 6 months prior to BSSO and Group II, where intra-operative removal of contralateral third molars were done for the same patients during the osteotomy. The primary outcome variable studied was postoperative infection rate and the secondary outcome variable was bad split during BSSO.Among the seventy five patients (150 sites), one site in group II developed infection whereas none of the sites in group I developed infection (p = 1.000). No sites had bad split in both the groups.The results from the present study show that there is no difference between the presence or absence of mandibular third molars on post-operative wound infection following bilateral sagittal split osteotomy, and the authors hence suggest removing third molars during BSSO for patient comfort.     

Changes in quality of life after surgical removal of impacted mandibular third molar teeth

Background  

The decision to get impacted teeth removed is not straightforward because of the concerns about its possible outcome. Assessment of quality of life is now regarded as an essential component for assessing outcomes of dental health care. The purpose of this paper is to assess the effect of impacted third molar teeth surgery on a number of health related outcomes.     

Effect of premolar extraction on mandibular third molar impaction in young adults

Objective:To test the null hypothesis that orthodontic therapy with or without premolar extraction does not result in any difference in third molar impaction.Materials and Methods:Two groups were formed: 22 patients in one group with first premolar extractions and 22 patients in the other group without extractions. All patients were nongrowing subjects who had normal gonial angles and were skeletal Class I at the beginning of treatment. The available space for third molars, inclination of second and third molars, and angle between the second and third molars were evaluated. Also, the correlation of measured parameters and type of orthodontic therapy with the eruption of third molars was evaluated.Results:Of the third molars, 81.8% were impacted in the nonextraction group and 63.6% were impacted in the extraction group. Impaction of mandibular third molars was significantly correlated to the pretreatment and posttreatment inclination of third molars and the angle between the second and third molars. In the extraction therapy group, the retromolar distance increased significantly with a mean of 1.30 ± 1.25 mm.Conclusions:When the inclination of the third molar is inconvenient, the tooth may remain impacted even if there is enough retromolar space.     

下颌第三磨牙萌出状态与舌侧骨板厚度的相关性分析

目的 分析下颌第三磨牙不同萌出状态与舌侧骨板厚度的相关性。方法 选取2016年1月—2018年12月在同济大学附属上海市第四人民医院接受下颌第三磨牙拔除术的患者187例,收集术前拔牙区锥形术CT(CBCT)影像。利用GALIEOS Viewer软件,测量下颌第三磨牙牙根中点和根尖区的舌侧骨板厚度,分析第三磨牙萌出状态与舌侧骨板厚度的相关性。采用 SPSS 22.0 软件包对数据进行Wilcoxon检验、单因素和多因素Logistic回归分析。结果 第三磨牙牙根中点区舌侧骨板的平均厚度小于根尖区(P<0.01)。牙根中点区骨板的厚度与第三磨牙的近远中向角度有关,近中阻生和水平阻生的第三磨牙,舌侧骨板较薄(P<0.01)。根尖区骨板的厚度与第三磨牙的阻生深度有关,中位和低位阻生的第三磨牙,舌侧骨板较薄(P<0.05)。结论 下颌第三磨牙舌侧骨板厚度与第三磨牙的萌出状态有关。近中、水平阻生和中位、低位阻生的第三磨牙,舌侧骨板较薄。拔牙时应避免舌侧骨板发生折裂。     

Randomized clinical study comparing Piezoelectric Surgery with conventional rotatory osteotomy in mandibular third molars surgeries

PurposeThe aim of this study was to evaluate the performance and to assess the postoperative sequel and quality of life after removal of impacted mandibular third molars using piezoelectric surgery compared with conventional rotatory osteotomy.Patients and methodsA single blinded, randomized, control clinical study was performed. Sixty-three patients (44 males, 19 females) who presented with bilaterally asymptomatic impacted mandibular third molars were included in this analysis. Each patient was treated, at two separate sessions approximately 4 weeks apart, with a conventional rotatory hand piece on one side of the mandible and a piezoelectric device on the contralateral side. Patients were followed up on postoperative days 1, 3, 5, 7, and 15 to rate the pain, swelling and trismus. Inferior alveolar nerve paresthesia was evaluated up to 12 months postoperatively.ResultsThe severity of the pain, trismus and swelling using the piezosurgery were significantly different from the rotary group. In both groups, pain was most intense and peaked during the first post-operative day, while swelling and trismus reached peak levels on the third postoperative day. The piezoelectric procedure resulted in a significantly longer procedural duration compared to the rotatory surgery (P < 0.001).ConclusionPiezoelectric surgery is considered a viable alternative technique compared to the conventional rotary systems and can improve a patient’s quality of life. Thus, piezoelectric surgery might be a preferred modality for patients undergoing complicated surgical extraction of impacted lower third molars.     

Effect of submucosal and intramuscular dexamethasone on postoperative sequelae after third molar surgery: comparative study

We compared the effects of dexamethasone sodium phosphate given submucosally and intramuscularly on postoperative complications after removal of impacted lower third molars in a preliminary randomised prospective clinical trial. Thirty patients, each of whom required removal of a single impacted mandibular third molar under local anaesthesia, were randomly allocated to one of 3 groups of 10 each. The 2 experimental groups were given dexamethasone 4 mg submucosally or intramuscularly, and the control group had no steroid. Facial swelling and maximal interincisal distance were measured by an independent examiner at baseline (preoperatively), and at 1, 3, and 7 days postoperatively. Pain was measured by counting the number of rescue analgesic tablets taken, and from the patients’ response to a visual analogue scale (VAS). The mean age of the 16 men and 14 women was 27 years (range 20–48). Both dexamethasone groups showed significant reductions in swelling (p < 0.001) and in pain (p < 0.05) compared with the control group at all intervals. Submucosal dexamethasone resulted in significantly less trismus than controls on day 1 postoperatively (p = 0.04), but there were no significant differences among the groups at the other times. The effects of the two routes of dexamethasone were comparable for all variables. There were no cases of alveolar osteitis or wound infection. Dexamethasone 4 mg given submucosally is an effective way of minimising swelling, trismus, and pain after removal of impacted lower third molars, and is comparable with the intramuscular route. It offers a simple, safe, painless, non-invasive, and cost-effective treatment in moderate and severe cases.     

下颌骨埋伏阻生智牙2种方法拔除的交叉试验研究

目的:对2种拔除下颌骨埋伏阻生智牙方法的临床效果进行比较。方法:选取双侧阻生情况相似的下颌骨埋伏阻生智牙拔除患者15例,左右两侧手术相隔2周,分别采用侧入法(经下颌骨外斜线途径)和常规的上入法(经牙槽嵴顶途径)拔除两侧智牙,记录手术时间、术后反应及并发症情况,采用配对t检验进行统计学分析。结果:侧入法组手术时间(66.73±19.26)min,明显短于上入法组的(91.20±39.19)min,两者有显著性差异(P=0.0026);肿胀情况:侧入法组较上入法组明显(P=0.0233);术后疼痛及张口度情况两组之间差别不大。上入法拔除组术后有4例伤口延期愈合,4例发生一过性下唇麻木;侧入法组伤口均一期愈合,有2例发生一过性下唇麻木。结论:使用侧入法拔除下颌骨内埋伏阻生智牙特别适用于埋伏牙位置深、对保持术区牙槽嵴高度要求高的病例。     

Effect of manuka honey socket dressing on postoperative sequelae and complications following third molar extraction: A randomized controlled study

To evaluate the effect of manuka honey on the healing of mandibular third molar extraction sockets.This was a prospective randomized study at a tertiary health institution in Lagos, Nigeria. All extractions were transalveolar, using the distobuccal bone guttering technique. Participants were randomized into two study groups. Group A underwent intrasocket application of manuka honey, after which sockets were completely closed using the mucosal flap, while participants in group B underwent mucosal flap closure of the socket without application of manuka honey. The primary outcome was healing of the extraction socket at 7 days postoperatively. The secondary outcomes measured were postoperative sequelae, namely pain, swelling, and trismus on postoperative days 1, 3, and 7, and socket healing complications — specifically inflamed socket, infected socket, and alveolar osteitis.In total, 112 participants completed the study, with 56 participants per group. There were no significant differences in demographic variables between both groups. On the 7th day postoperatively, 26.8% of participants in group B had an unhealed extraction site, compared with 10.3% of participants in group A (p = 0.029).A significant difference was observed between pre- and postoperative pain scores in both study groups (p = 0.001). A comparison of postoperative mean facial swelling between the two groups showed no statistically significant differences on all the review days (p = 0.66). The difference in postoperative socket healing complication rate between both groups was statistically significant (χ² = 4.747, p = 0.029).Within the limitations of the study it seems that the application of manuka honey appears to aid earlier healing of the third molar extraction socket, with a significantly lower frequency of complications. Therefore, the application of manuka honey is recommended whenever appropriate.     

下颌阻生第三磨牙分段切割拔除术的选择

目的 探讨用涡轮机分段切割法拔除下颌中、低位阻生的第三磨牙的效果及适应证。方法 对481例675颗曲面体层片显示中、低位阻生的下颌第三磨牙用涡轮机分段切割法拔除。其中327颗实施二段切割法;348颗实施三段切割法。结果 下颌阻生第三磨牙均完全拔除;手术时间5~20 min（平均16 min）;术后发生短暂下唇麻木症状3例（3颗）,发生术后感染15例（15颗）。结论 二段切割法适用于中位近中阻生的下颌第三磨牙,三段切割法适用于中/低位近中、水平阻生的下颌第三磨牙。     

正畸治疗中磨牙的拔除和保留(二十六)——第三磨牙发生和发育状况的研究

目的:调查第三磨牙的发生和发育情况.方法:对870名8～18岁青少年全牙列曲面断层片进行统计分析.结果:第三磨牙牙胚发生率趋于稳定的时间下颌早于上颌约1年;男14岁,女13岁起第三磨牙的发生率趋于稳定;上颌第三磨牙缺失率约为17%,下颌约为12%;个体缺失4个、3个、2个和1个第三磨牙的比例分别是5.06%、3.86%、8.92%和10.84%;上颌第三磨牙与第二磨牙的牙冠近远中宽度比主要集中在0.9 0.1,而下颌集中在1.0 0.1的范围内;第三磨牙的发育阶段个体年龄差异较大.结论:对第三磨牙的发生、发育及牙冠大小的评估对于口腔各专业学科均有参考价值.     

改良三角瓣对下颌第三磨牙拔除术后并发症的影响及其临床应用

目的 通过对比改良三角瓣与传统三角瓣对下颌近中阻生第三磨牙拔除术后并发症的影响,探讨改良三角瓣的临床应用.方法 选取110例门诊就诊需要拔除第三磨牙的患者,随机分为2组:改良三角瓣组和传统三角瓣组,记录患者术后2、7d的疼痛程度、肿胀程度和张口受限程度,进行组间比较.结果 术后2d,改良三角瓣组的肿胀程度(Z=-3.432)和张口受限程度(t=19.188)均小于传统三角瓣组,其差异有统计学意义(P＜0.05),但术后7d无此差别(P＞0.05).而在疼痛程度方面,两者在术后2d和术后7d均未看到明显差异(P＞0.05).结论 与传统三角瓣相比,改良三角瓣早期并发症更轻,熟练掌握后操作更容易,值得推广.     

Eruption of mandibular third molars after second-molar extractions: a radiographic study

The purpose of the present study was to analyze the posteruptive contact relationship and inclination of mandibular third molars after extraction of second molars and to determine whether predictors could be formulated for the dental relationships observed. In all, 140 mandibular quadrants were evaluated from 95 sets of panoramic radiographs taken at the time of second molar extraction (T1) and at the time of final evaluation (T2). For analysis of a consecutive sample of patients, a subsample of 25 sets of radiographs from all the patients who had received such treatment during one calendar year was also quantified. Subjective evaluation indicated that 46% of the sites examined had satisfactory tooth contact relationship between the first and third molars at T2. Third-molar impaction was found in 4% of the sites in the subsample of 25 consecutively treated patients. Measurements of crown axis inclination revealed that the third molar invariably erupted into a mesially tilted position. The first molar showed only minor distal tipping between T1 and T2. Inclination of the third molar bud at the time of second molar extraction was not found to be a useful predictor for posteruptive third molar position. The clinical significance of these results and the need for studies regarding a rationale for mandibular second molar extraction are discussed.