The wand in pulp therapy: an alternative to inferior alveolar nerve block.

OBJECTIVES: The purpose of the study was to compare children's reactions to inferior alveolar nerve injection with traditional syringe and periodontal ligament injection with a computerized device (Wand); and to assess the efficacy of the anesthesia and their reaction after treatment. METHOD AND MATERIALS: Twenty-five children, aged 6 to 10 years, participated in the study. The contralateral primary mandibular second molars were treated in 2 separate visits with random use of either the Wand or traditional syringe injection. The pain perception levels for each step were assessed with Eland Color Scale during the preparation. A Mann-Whitney U test was performed to compare the results. The patients were asked their preference of technique after the treatment. RESULTS: When pain was measured immediately after injection, the traditional syringe was found to be more painful than injections with the Wand (P < .05). Pain scores with the Wand injections were found to be significantly (P < .05) higher than those with traditional inferior alveolar nerve injections at the end of the restoration. The overwhelming majority of patients favored the periodontal ligament injection with the Wand. CONCLUSION: The Wand technique provided significantly lower pain scores during the periodontal ligament injection. However, the pain scores during the treatment were significantly higher compared with the inferior alveolar nerve injections. Most of the patients stated that they preferred the periodontal ligament injection with the Wand to the traditional inferior alveolar nerve injection.     

Pain perception and utility: a comparison of the syringe and computerized local injection techniques

Thirty patients received maxillary infiltration and mandibular inferior alveolar nerve block injections with both a traditional syringe and a computerized system, the Wand. Patients noted their preference for either system and rated their injection pain and postoperative discomfort on a ten-point scale for each type of injection. Mean injection discomfort ratings with the Wand were lower than with the syringe but were not statistically significant. Reduced postoperative discomfort using the Wand for the inferior alveolar nerve block was significant. Both of the dentists in the study and those patients who stated a preference favored the Wand system.     

The pharmacokinetics and cardiovascular effects of high-dose articaine with 1:100,000 and 1:200,000 epinephrine

OBJECTIVES: The authors conducted a randomized, double-blind, two-way crossover clinical trial to compare the pharmacokinetics and cardiovascular effects of 11.9 milliliters of 4 percent articaine hydrochloride (HCl) plus 1:100,000 epinephrine (A100) with those of 11.9 mL of 4 percent articaine HCl plus 1:200,000 epinephrine (A200). METHODS: During two testing sessions, the authors administered injections of A100 and A200 over a seven-minute period (in one-cartridge doses unless otherwise noted): maxillary right first molar infiltration, maxillary left first molar infiltration, maxillary right first premolar infiltration, maxillary left first premolar infiltration, right inferior alveolar injection, left inferior alveolar injection, right long buccal infiltration (one-half cartridge) and left long buccal infiltration (one-half cartridge). They analyzed venous blood samples for articaine levels. They used noninvasive acoustic tonometry to measure a variety of cardiovascular parameters over a two-hour period. RESULTS: Plasma concentration curves of articaine over time were similar for both solutions, with peak concentrations and times to maximum concentration being 2,037 nanograms per milliliter and 22 minutes for A100 and 2,145 ng/mL and 22 minutes for A200. At the 10-minute point, the mean systolic blood pressure and heart rate were significantly elevated (P < .05) with A100 versus A200. CONCLUSIONS: Maximum dose recommendations for the A100 solution also can be applied to the A200 solution. A200 produces less cardiovascular stimulation than does A100. CLINICAL IMPLICATIONS: A200 is as safe as A100, and may be preferable to A100 in patients with cardiovascular disease and in those taking drugs that reportedly enhance the systemic effects of epinephrine.     

Injection pain and postinjection pain of the anterior middle superior alveolar injection administered with the Wand or conventional syringe

OBJECTIVE: The purpose of this prospective, randomized, blinded study was to compare the pain of injection and post-injection pain of the AMSA injection using the computer-assisted Wand Plus injection system versus a conventional syringe. STUDY DESIGN: Using a crossover design, 40 subjects randomly received 2 blinded AMSA injections using the Wand Plus system and a conventional syringe, at 2 separate appointments. The AMSA injection site was centered halfway between the midpalatine raphe and gingival margin of the first and second premolars. The pain of needle insertion, anesthetic solution deposition pain, and postinjection pain were recorded on a Heft-Parker VAS for the 2 AMSA injections. RESULTS: For needle insertion, 38% of the subjects had moderate/severe pain with the Wand Plus((R)) and 34% moderate/severe pain with the conventional syringe, with no significant difference between techniques. There was a significant difference for solution deposition pain, with the conventional syringe causing more moderate/severe pain (42% conventional vs. 25% for the Wand Plus. Regarding postinjection pain, after numbness wore off there was no significant difference between the Wand Plus injection technique (0% moderate pain) and the conventional syringe technique (8% moderate pain). Postinjection, approximately 8% to 10% of the subjects experienced slight palatal swelling and 2% experienced temporary numbness. These problems resolved quickly and were considered minor. CONCLUSIONS: The AMSA injection, using the Wand Plus, resulted in similar pain ratings for needle insertion as the conventional syringe but statistically lower pain ratings upon anesthetic solution deposition. However, the AMSA, using either the Wand Plus or a conventional syringe, has the potential to be a painful injection. We found the incidence of postinjection pain and sequelae was low with both techniques.     

The wand versus traditional injection for mandibular nerve block in children and adolescents: perceived pain and time of onset

PURPOSE: The purpose of this study was to compare the perception of pain and time of onset in relation to mandibular alveolar nerve block administered by a computerized anesthesia delivery system (ie, The Wand) and a traditional anesthesia system (ie, the syringe). METHODS: This study was conducted according to a split-mouth design, with both types of injections being given to all patients. Subjects consisted of 33 patients between 7 and 18 years of age requiring local anesthesia for dental restorations in both sides of the mandible. All patients were blindfolded, and the sound from the Wand machine was activated during both types of administration. Topical analgesic was placed in the area of the injection site in all cases. Pain ratings were obtained using a 10-point visual analog scale (VAS). Time of onset was measured, from withdrawal of the needle to numbness of the lower lip was reported. RESULTS: The computerized anesthesia delivery system resulted in significantly lower pain ratings than the traditional syringe. No difference could be found in time of onset between the 2 methods. CONCLUSIONS: Mandibular alveolar block analgesia seems to be less painful when using The Wand than when using a traditional syringe.     

急性牙髓炎应用无痛局麻仪进行牙周膜麻醉的临床评价

目的：病例应用无痛局麻注射仪对神经阻滞麻醉失败病例进行牙周膜注射的疼痛程度及注射效果进行评价。方法：本组90例,采用无痛局麻注射仪进行牙周膜麻醉,与传统的手推式加压牙周膜麻醉对比。结果：应用无痛局麻注射仪进行牙周膜麻醉时,注射时疼痛程度明显小于手推式加压麻醉法。牙髓治疗时的麻醉效果两者无明显差别。但前者的成功率高于后者。阿替卡因注射时镇痛效果明显优于利多卡因,并且麻醉效果更好。     

Efficacy of anterior and middle superior alveolar (AMSA) anesthesia using a new injection system: the Wand.

OBJECTIVE: This study examined the effect of anterior and middle superior alveolar (AMSA) field block of maxillary nerves using a new local anesthetic system--the Wand. METHOD AND MATERIALS: Twenty healthy volunteers aged 23 to 44 years were used in the study. Either side of the maxillary teeth was randomly selected for AMSA injection; the other side was left as a control. For each side, 1.8 mL of 2% lidocaine solution with 1/80,000 epinephrine was injected by the Wand on a point that bisects the maxillary first and second premolars and is midway between the crest of the free gingival margin and the midpalatine suture. Pain rating score (PRS) and visual analogue scale (VAS) were applied for measurement of puncture, insertion, and injection pain. Electric pulp stimulation was given to each maxillary tooth every 10 minutes for 1 hour after the injection in order to find out the specific tooth on which AMSA injection was effective. RESULTS: During needle insertion, 14 out of 20 subjects answered moderate pain and VAS showed 27.3 mm (mean). During injection, 11 of 20 revealed no pain and the mean of VAS was 14.5 mm. No one claimed severe pain by PRS. Electric pulp stimulation indicated that lateral incisors, canines, and first and second premolars were more anesthetized than central incisors and first molars. CONCLUSION: AMSA injection using the Wand method seems to avoid severe injection pain and seems to be very effective for pulpal anesthesia at lateral incisors, canines, and premolars.     

Injury of the inferior alveolar nerve after overfilling of the root canal with endodontic cement: a case report

The inferior alveolar nerve (IAN) contains mainly sensory fibers. Within the mandibular canal, the IAN runs forward in company of the inferior alveolar artery, and together they are called the inferior alveolar neurovascular bundle. Disturbances of the IAN and mental nerve will predominantly give sensitivity symptoms in the soft tissue of the lower lip and chin. We present a case report of endodontic overfilling involving the mandibular canal. A 52-year-old woman was seen in our outpatient clinic for pain and numbness in the left lower lip and chin, which developed following an endodontic treatment for her mandibular left second premolar. The panoramic radiograph showed radiopaque material in the inferior alveolar canal region, with an extension from the left canine to the second premolar. This case report shows an unusual complication of mandibular second premolar root canal overfilling. The patient underwent treatment with corticosteroids, and after 2 months, the clinical examination revealed an improved clinical situation with a disappearance of the hypoesthesia but with a persistence of the pain. After 4 months, the pain had almost entirely disappeared. In conclusion, even if in our case no surgical treatment was used and although spontaneous resorption has been described for some materials, early surgical exploration with removal of the material and decompression of the IAN is suggested, irrespective of the material used, because the severity of nerve damage can increase with the duration of the injury.     

Computer-controlled delivery versus syringe delivery of local anesthetic injections for therapeutic scaling and root planing

BACKGROUND: The authors conducted a study to compare administration of local anesthetic using a computer-controlled delivery device with an aspirating syringe for therapeutic scaling and root planing. The anterior middle superior alveolar, or AMSA, injection was compared with other maxillary injections. METHODS: Twenty healthy adults with moderate periodontal disease participated in this single-blind crossover study. Subjects were evaluated by a trained examiner and were treated by experienced dental hygienists. Subjects provided written and verbal pain ratings via a visual analog scale, or VAS, and a verbal rating scale, or VRS. AMSA injections were compared with syringe-delivered injections--greater palatine, or GP, and nasopalatine, or NP, blocks, and anterior superior alveolar and middle superior alveolar injections--in maxillary quadrants. Bleeding and changes in attachment were evaluated after one month. RESULTS: VAS and VRS scores for AMSA were significantly lower for computer-controlled delivery when compared with NP injections and combined maxillary injections (VAS scores) and with GP and combined maxillary injections (VRS scores). Mean injection times were similar for both groups. Mean gains in attachment were equal, 0.19 millimeters for quadrants anesthetized using computer-controlled injections and 0.22 mm for syringe injections. CONCLUSIONS: Subjects reported having less pain with GP and NP injections delivered using the computer-controlled device, and total injection time was similar to that required for syringe injections. Both techniques provided adequate anesthesia for therapeutic scaling and root planing. Clinical Implications. The two anesthetic delivery techniques were therapeutically equivalent for mandibular injections, and the AMSA injection has clinically significant advantages for maxillary injections.     

Case challenge. Chronic maxillary inflammation

A 30-year old male was referred by a dental practitioner to the Department of Oral Radiology at the University of Lund, Sweden, for a radiological evaluation of chronic symptoms of inflammation on the right side of the maxilla. According to the patient, at age 12 he had surgery to remove a non-erupted maxillary right second premolar. Postoperatively, a draining sinus tract appeared on the buccal aspect of the alveolar process. Thirteen years later, at age 25, surgery was again performed and the sinus tract reappeared. Intermittent discharge of exudate from the sinus tract occurred since the second surgery. Clinical and radiological examinations were conducted prior to a third surgery. The clinical examination revealed pus draining from the tract located on the buccal aspect of the alveolar process between the right maxillary first molar and first premolar. The radiological examination included periapical radiographs of the right maxillary first premolar and canine, a panoramic radiograph, and frontal tomograms of the maxillary right premolar area.     

Anesthetic efficacy and heart rate effects of the supplemental intraosseous injection of 2% mepivacaine with 1:20,000 levonordefrin

OBJECTIVE: The purpose of this study was to determine the anesthetic efficacy and heart rate effects of a supplemental intraosseous injection of 2% mepivacaine with 1:20,000 levonordefrin. STUDY DESIGN: Through use of a repeated-measures design, 40 subjects randomly received 3 combinations of injections at 3 separate appointments. The combinations were as follows: inferior alveolar nerve (IAN) block (with 3% mepivacaine) + intraosseous injection of 1.8 mL of 2% mepivacaine with 1:20,000 levonordefrin; IAN block + intraosseous injection of 1.8 mL of 2% lidocaine with 1:100,000 epinephrine (positive control); IAN block + mock intraosseous injection (negative control). Each first molar, second molar, and second premolar was blindly tested with a pulp tester at 2-minute cycles for 60 minutes after injection. Anesthesia was considered successful when 2 consecutive readings of 80 were obtained. Heart rate (pulse rate) was measured with a pulse oximeter. RESULTS: One hundred percent of the subjects had lip numbness with the IAN block + intraosseous mock technique and IAN block + intraosseous techniques. The anesthetic success rates for IAN block + mock intraosseous injection, IAN block + intraosseous lidocaine, and IAN block + intraosseous mepivacaine, respectively, were as follows: 80%, 100%, and 100% for the first molar; 90%, 100%, and 100% for the second molar; 77%, 97%, and 97% for the second premolar. For the first molar and second premolar, the differences were significant (P< .05) when the intraosseous mepivacaine and lidocaine techniques were compared with the IAN block + mock intraosseous injection. There were no significant differences between the intraosseous mepivacaine and lidocaine techniques. Eighty percent of the subjects had a mean increase in heart rate of 23-24 beats per minute with the intraosseous injection of the mepivacaine and lidocaine solutions; there were no significant differences between results with the 2 solutions. CONCLUSIONS: We concluded that intraosseous injection of 1.8 mL of 2% lidocaine with 1:100,000 epinephrine or 2% mepivacaine with 1:20,000 levonordefrin, used to supplement an IAN block, significantly increased anesthetic success in first molars and second premolars. The 2 solutions were equivalent with regard to intraosseous anesthetic success rate, failure rate, and heart rate increase after IAN block.     

Injection pain and postinjection pain of the palatal-anterior superior alveolar injection, administered with the Wand Plus system, comparing 2% lidocaine with 1:100,000 epinephrine to 3% mepivacaine

PURPOSE: The purpose of this prospective, randomized, double-blind study was to compare injection pain and postinjection pain of 2% lidocaine with 1:100,000 epinephrine and 3% mepivacaine using the computer-assisted Wand Plus injection system to administer the palatal-anterior superior alveolar (P-ASA) injection. Additionally study was done to determine if the use of topical anesthetic decreased the pain of needle insertion with the P-ASA injection. STUDY DESIGN: Using a crossover design, 40 subjects randomly received, in a double-blind manner, P-ASA injections of 1.4 mL of 2% lidocaine with 1:100,000 epinephrine and 1.4 mL of 3% mepivacaine, at 2 separate appointments. The P-ASA injection was administered, utilizing the Wand Plus system, 6 to 10 mm into the incisive canal located lingual to the central incisors. The pain of needle insertion, needle placement, solution deposition and postinjection pain were recorded on a Heft-Parker visual analog scale for the 2 P-ASA injections. Eighty injections were randomly administered in the study, 40 using topical anesthetic gel and 40 using a placebo gel. RESULTS: For needle insertion, 30% of the subjects reported moderate/severe pain with the lidocaine solution and 43% reported moderate/severe pain with the mepivacaine solution. There was no significant difference (P > .05) between the topical and placebo groups. For needle placement into the incisive canal, 54% of the subjects reported moderate/severe pain with the lidocaine solution and 58% reported moderate/severe pain with the mepivacaine solution. For anesthetic solution deposition, 8% of the subjects reported moderate pain with the lidocaine solution and 12% reported moderate pain with the mepivacaine solution. There were no significant differences (P > .05) between the lidocaine and mepivacaine solutions. Regarding postinjection pain, when anesthesia wore off on the day of the injection, 20% of the subjects reported moderate/severe pain with the lidocaine solution and 14% reported moderate/severe pain with the mepivacaine solution. Pain ratings decreased over the next 3 days. There were no significant differences (P > .05) between the lidocaine and mepivacaine solutions. Postinjection, 12% and 18% of the subjects experienced temporary numbness/paresthesia of the incisive papilla with the lidocaine and mepivacaine solutions, respectively. Twenty percent and 28% of the subjects had incisive papilla swelling or soreness with the lidocaine and mepivacaine solutions, respectively. There were no significant differences (P > .05) between the lidocaine and mepivacaine solutions. CONCLUSIONS: The P-ASA injection of 1.4 mL of 2% lidocaine with 1:100,000 epinephrine or 3% mepivacaine, administered with the Wand Plus, has the potential to be a painful injection. The use of topical anesthetic did not significantly reduce pain of needle insertion when compared to a placebo. The incidence of postinjection pain, temporary numbness/paresthesia, and incisive papilla swelling or soreness would indicate that some pain and problems occur with the P-ASA technique, regardless of whether 2% lidocaine with 1:100,000 epinephrine or 3% mepivacaine is used.     

上颌全口义齿的加强结构对基托下黏膜应力分布的影响

目的：分析上颌全口义齿加强前后及不同的加强设计，对基托下黏膜应力分布的影响。方法：采用三维有限元法，建立无加强（BS），铸造结构加强BA，BD和BDr等4种上颌全口义齿三维有限元模型。设定P1，M1，PMc和PMe等4种垂直加载条件，加载力合计98N。对全口义齿基托下黏膜的应力分布进行分析。结果：在相同加载条件下，黏膜应力峰值表示为按BS，BA，BD，BDr的顺序依次减小。BDr基托下黏膜应力峰值最小，应力分布更均匀和广泛。结论：使用覆盖牙槽嵴顶及后堤区的铸造加强结构的上颌全口义齿能够使基托下黏膜应力分布更均匀和广泛，有利于保护基托下黏膜组织。     

Quality of anesthesia for the maxillary primary anterior segment in pediatric patients: comparison of the P-ASA nerve block using CompuMed delivery system vs traditional supraperiosteal injections

PURPOSE: The purpose of this study was to compare the quality of 2 injection techniques to anesthetize the maxillary primary anterior segment by applying either the palatal approach anterior superior alveolar nerve block (P-ASA) utilizing a computer-controlled injection device (CompuMed with the Wand handpiece) or traditional multiple supraperiosteal (TMS) injections with a hand-operated syringe. Depth and duration of anesthesia was assessed by the number of disruptive behaviors 20 minutes following injection. METHODS: Twenty-one preschoolers aged 3 to 5 years, who required pulp tissue removal with subsequent crown placement and/or extraction of at least 2 teeth in the maxillary incisor segment on opposite sides of the midline, participated in this study. They were randomly assigned to either the P-ASA or the TMS injection group. The procedure was separated into 3 segments: (1) the injection; (2) overall procedure; and (3) painful event. Each segment was scored for disruptive behaviors (body movements, crying, restraint, or dentist interference) using an established scale. Scores were analyzed via analysis of variance for significance. RESULTS: During injection, disruptive behaviors occurred significantly less in the P-ASA group than in the TMS group. No significant differences were found between the 2 groups for the overall procedure and the painful event segments. CONCLUSION: Whereas anesthetic solution delivery with CompuMed system caused significantly less disruptive behavior during the injection phase, both methods seem to provide a comparable quality of anesthesia for the maxillary primary incisor segment 20 minutes after deposition of the anesthetic solution.     

Alveolar process fractal dimension and postcranial bone density

OBJECTIVES: Our goal was to determine whether the radiographic fractal dimension of the maxillary and mandibular alveolar processes is related to bone density of the alveolar processes, spine, hip, and radius in healthy women. STUDY DESIGN: Thirty-seven dentate healthy white women aged 20 to 78 years underwent assessment of systemic and alveolar process bone. After a periodontal examination, D-speed vertical bite-wing and periapical radiographs with aluminum step wedges and a density correction algorithm were used to make alveolar process fractal dimension and density calculations within regions of interest that avoided crestal bone and intrabony defects. Anteroposterior (L1-L4) and lateral (L2-L4) lumbar spine, total hip, and total wrist densities were determined by means of dual energy x-ray absorptiometry. RESULTS: Correlation analysis revealed significant relationships between maxillary alveolar process fractal dimension and maxillary alveolar process density (r = 0.47, P < or =.01), mandibular alveolar process density (r = 0.48, P < or =.01), and mandibular alveolar process fractal dimension (r = 0.44, P < or =.05); and between mandibular alveolar process fractal dimension and maxillary alveolar process density (r = 0.54, P < or =.01) and mandibular alveolar process density (r = 0.58, P < or =.001). No significant relationships were found between the maxillary alveolar process or the mandibular alveolar process fractal dimension and the density of any postcranial regions. CONCLUSIONS: In healthy women, the alveolar process radiographic fractal dimension is significantly related to the alveolar process density but is not related to the density of the spine, hip, or radius.     

双侧上颌第一前磨牙牙体对称性研究

目的：研究左右离体上颌第一前磨牙牙体的对称性。方法：筛选40位正畸患者新近拔除的双侧年轻上颌第一前磨牙共80颗作为研究对象。使用电子游标卡尺分别对牙体全长、冠长、根长、牙冠、牙颈及根中1/2的宽和厚等10个数据进行测量,测量结果使用SPSS 16.0软件进行统计分析。结果：所有40位患者左右上颌第一前磨牙在牙体外部形态上无统计学差异（P〉0.05）。结论：左右上颌第一前磨牙牙体外部形态存在一定的对称性,变异较小。     

上颌口腔腭侧黏膜疼痛敏感度的初步研究

目的:研究不同部位口腔上颌腭侧黏膜疼痛敏感度,发现相对敏感区域并提出相应对策,以减轻患者注射麻药时的疼痛感及全身并发证的发生。方法:对需拔除的上颌患牙进行局部浸润麻醉,采用碧兰麻及相对应的0.3mm×21mm细针头,注射部位距离腭侧牙龈缘约5mm,后记录注射部位的疼痛程度,所记录的疼痛程度是注射针刺入黏膜时的疼痛。疼痛分级采用国际通用方法,但加以改良,使之更详细。采用χ2检验分析各牙位的中重度和重度疼痛患者构成比。结果:800例患者中,无痛到中度疼痛患者646例,占总数的80.75%;中重度和重度疼痛患者154例,占19.25%。中重度和重度疼痛患者在中切牙组占47%,侧切牙组占39%,尖牙组占27%,第一前磨牙组占12%,第二前磨牙组占9%,第一磨牙和第二磨牙组均占8%,上颌结节区占4%。与前磨牙、磨牙和上颌结节区相比,中切牙、侧切牙和尖牙组的中重度和重度疼痛患者比例明显增加,差异有统计学意义(χ2检验,P<0.01)。结论:中切牙、侧切牙和尖牙腭侧黏膜疼痛敏感度较高,先表面麻醉后再注射麻药,以减少患者的疼痛感,同时减少患者的恐惧感和全身并发症的发生。     

上颌牙槽突颊舌向生理倾斜角的锥形束CT研究

目的    采用锥形束CT（CBCT）影像测量上颌牙槽突颊舌向生理倾斜角,为种植体植入位置和方向的确定提供参考。方法    按照事先制定的纳入与排除标准,从中国人民解放军总医院口腔医学中心影像数据库中随机抽取2014年11月至2015年11月初次就诊患者拍摄的CBCT影像51份（均由NewTom 5G设备拍摄）。采用NewTom 5G自带软件进行重建,重建区域上下边界与上颌牙牙合平面平行,采用0.5 mm层厚、5 mm层间距,在牙列弧形线上对牙槽突进行垂直切割,获得上颌牙槽突的24个等间距的颊舌向断面。使用NNT 5.6软件测量每个颊舌向切面的牙槽突倾角。结果    按从右上颌最后一个层面（第2层）到左上颌最后一个层面（第23层）的顺序,上颌各层面牙槽突倾角平均值或中位值分别为：0°、0°、0°、0°、10.2°、17.4°、23.9°、31.9°、40.7°、42.3°、31.8°、32.6°、41.7°、40.7°、31.8°、22.9°、16.1°、8.2°、0°、0°、0°、0°。左右对称层面牙槽突倾角差异无统计学意义（P > 0.05）。男女之间的牙槽突倾角差异无统计学意义（P > 0.05）。第2～5层和第20～23层（对应于磨牙区）中,牙槽突倾角为0°的牙槽突比例高于颊侧倾斜牙槽突（P < 0.05）。结论    前牙区牙槽突倾角最大,前磨牙区倾角次之,磨牙区倾角逐渐递减为0。前牙区和前磨牙区牙槽突向唇、颊侧倾斜,磨牙区牙槽突在多数情况下呈垂直向,其次为向颊侧倾斜。了解牙槽突倾角有助于种植体植入位置和方向的确定,在不具备种植手术导板的情况下,其参考作用尤其明显。     

拔除上颌第一前磨牙正畸患者治疗后上颌前牙骨开窗骨开裂的初步研究

目的用CBCT评价拔除上颌第一前磨牙正畸治疗后患者的上颌前牙骨开窗骨开裂的发生情况,为正畸治疗内收上前牙避免骨开窗骨开裂提供参考依据。方法选择35例上颌拔除第一前磨牙并用最大支抗内收前牙的正畸治疗后患者的CBCT图像,获得上颌前牙样本210例。使用SimPlant Pro 13.0调整头位,获得三维层面中待检测牙齿直立的CBCT图像,测量矢状切面中唇舌侧釉牙骨质界到牙槽嵴顶的距离,用卡方检验进行统计分析。由此评价正畸治疗后患者上颌前牙骨开窗骨开裂的情况。结果上颌中切牙侧切牙舌侧骨开裂骨开窗的发生率明显大于唇侧,且骨开裂的差异具有显著性。上颌尖牙唇侧骨开裂不小于舌侧骨开裂的发生率,唇侧骨开窗的发生率大于舌侧,但差异都不具有显著性。结论拔除上颌第一前磨牙正畸患者治疗后上颌切牙腭侧骨开裂发生率明显高于唇侧,在正畸治疗过程中要注意控制内收的限度。     

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??Objective    To measure the anatomic buccolingual angulation values of the maxillary alveolar process based on CBCT images in order to form a basis for the implant treatment planning?? including the design of implant position and angulation. Methods    A random sample of 51 CBCT images were selected and analyzed. The NewTom 5G CBCT data sets were reformatted at a 0.5-mm spacing?? with the inferior border of the region of interest parallel to the occlusion plane of maxillary teeth. Twenty-four buccolingual cross-sectional images of the maxillary alveolar process were obtained for buccolingual angulation measurements. Results    Mean or median values of the buccolingual angulation of maxillary alveolar process ranged from about 0 degree to more than 40 degrees. Cross-sections distal to the premolar region showed a statistically higher proportion of vertical process ??angulation equals to 0 degree???? compared to cross-sections corresponding to maxillary premolars and anterior teeth region ??P < 0.05??. There were no statistical differences between the angulation of alveolar process both from the right side and left side and from males and females patients ??P > 0.05??. Conclusion    The buccolingual angulation of maxillary alveolar process decreases from anterior teeth region through the premolars region to the molars region?? with the lateral incisor and canine region being the most inclined bucally and a high proportion of the molars region being nearly vertical. Knowing average values of buccolingual angulation of maxillary alveolar process before dental implantation may help the clinician plan the position and orientation of implants?? especially when an implant surgical template is not available.