Coralline porous hydroxyapatite as a bone graft substitute in orthognathic surgery: 24-month follow-up results

A 24-month postsurgical follow-up evaluation was performed on 49 patients (20 males and 29 females; mean age 26 years [range 9 to 52 years]) who had undergone orthognathic surgery in which coralline porous block hydroxyapatite (PBHA) was used as a bone graft substitute. Followup ranged from 23 to 45 months (average 27 months). One surgeon implanted all 215 blocks: 189 blocks to the maxilla, 19 blocks to the mandible, and seven blocks to the midfacial region. Of the 215 implants, 135 were positioned directly adjacent to the maxillary sinus. Nine patients had postsurgical complications: three developed sinusitis, which was treated with antibiotics and decongestants, four had midpalatal implants exposed intraorally during surgery that later required removal, one had a slight displacement of a mandibular implant that has remained in place, and one had an interdental implant exposed that was recontoured and covered with tissue. At the 24-month followup or later, only one of the 49 patients had complications or symptoms associated months postsurgery. These results strongly support the use of coralline PBHA along with bone plate fixation to provide predictable stability in orthognathic surgery.     

Rapid palatal expansion in the young adult: time for a paradigm shift?

A 19-year-old man presented for correction of a malocclusion that included a transverse maxillary deficiency. The patient was informed that he required orthognathic surgery to expand his upper jaw and correct his malocclusion, but he refused surgical expansion. Recent evidence indicates that rapid palatal expansion can be used without surgery in young adults; the decision was therefore made to treat the patient nonsurgically. Rapid palatal expansion of the maxillary arch was accomplished by means of a Hyrax appliance, with post-treatment radiographs revealing an opening of the midpalatal suture. The belief still persists among some clinicians that young adult patients require orthognathic surgery for palatal expansion, despite recent evidence supporting a nonsurgical approach after closure of the midpalatal suture.     

Surgically assisted rapid palatal expansion for management of transverse maxillary deficiency

Surgically assisted rapid palatal expansion (SA-RPE) is a combined orthodontic and surgical procedure which facilitates an increase in transverse maxillary width in skeletally mature adults. Many different techniques have been described. In 1992 Pogrel and associates described a conservative method of widening the maxilla. This procedure consisted of bilateral zygomatic buttress and midpalatal osteotomies combined with the use of a tooth-borne device postoperatively. Other moreradical SA-RPE procedures have been described in which more extensive osteotomies have been performed. Experience of SA-RPE using the simplified technique described by Pogrel et al is describe.     

Endoscopic sinus surgery for dental implant displacement into the maxillary sinus—a retrospective clinical study

The aims of this retrospective clinical study were to present our management protocol for the retrieval of impacted dental implants that have become displaced into the maxillary sinus cavity and to define the role of endoscopic sinus surgery in this setting. All 24 patients (25 implants) who underwent surgical retrieval of dental implants displaced into the maxillary sinus between 2012 and 2019 were included. Data on surgical interventions and complications were collected retrospectively. Eleven patients (46%) had chronic sinusitis associated with the migrated implant. All implants were successfully retrieved via transnasal endoscopic approach alone: 80% via a middle meatal antrostomy and 20% via a combined middle and inferior meatal antrostomy. Five patients required a concomitant transoral approach for oro-antral fistula repair. None required a transoral approach for displaced implant retrieval. All patients healed uneventfully without complications. Transnasal endoscopic sinus surgery via a middle meatal antrostomy or a combined middle and inferior antrostomy is recommended as the primary choice for dental implant retrieval from the maxillary sinus. A transoral approach should be performed simultaneously only for oro-antral fistula repair. This surgical protocol proved to be safe and efficient, and it obviated the need for osteotomies of the anterolateral maxillary wall.     

Surgical-orthodontic correction of transverse maxillary deficiency

A conservative osteotomy of the zygomaticomaxillary buttress in combination with a rapid palatal expansion appliance is a dependable technique for the treatment of horizontal maxillary deficiency in adults. This procedure has been used successfully in 56 patients in our series, but 17 patients (30 per cent) required a midpalatal osteotomy. In two patients, overexpansion was not achieved because of necrosis of the mucosa. In three other patients, expansion had to proceed at a slower pace because of mucosal ulceration. There have been no other complications. The procedure is indicated mainly in those patients with a horizontal deficiency who do not require subsequent surgery, but for some patients it may be the preliminary procedure. Twelve patients (21 per cent) had subsequent orthognathic surgery. Follow-up has been from 1 to 12 years and there has been no relapse. In our opinion, the zygomaticomaxillary buttress is the primary area of resistance to lateral movement of the maxilla by rapid maxillary expansion appliances.     

Tomographic assessment of nasal septal changes following surgical-orthodontic rapid maxillary expansion

Nine adult patients with transverse maxillary deficiency were examined for incidence of nasal septal deviation following surgical-orthodontic rapid maxillary expansion. The osteotomies for facilitation of maxillary expansion did not include sectioning of the nasal septum. The procedure did include sectioning of the lateral maxillary walls, the pterygomaxillary suture, and the midpalatal sutures. For each patient, four graduated coronal tomograms through the incisal, molar, tuberosity, and pterygoid areas were taken prior to and not less than 4 months after surgical intervention. Results showed no significant change in the nasal septal position from before to after surgery. Analysis of the nature of maxillary movement in the coronal plane revealed rotational as opposed to bodily expansion, with inferior rotation of the palatal vault. Significant increases in the available nasal airway space were recorded. These increases were attributed primarily to shrinkage of inflamed nasal mucosa. In view of the recorded data, surgical sectioning of the nasal septum to prevent septal deviation by surgical-orthodontic rapid maxillary expansion is not warranted.     

Chin augmentation with various alloplastic materials: a comparative study

This retrospective study of 62 patients compared three alloplastic materials used in chin augmentation: Proplast I (PI), Proplast II (PII), and porous block hydroxyapatite (PBHA). There were 25 patients with PI implants (average follow-up of 44.8 months), 25 patients with PII implants (average follow-up of 32.8 months), and 12 patients with PBHA implants (average followup of 19.1 months). Average bone resorption was 1.25 mm (range 0.00 to 3.30 mm) beneath the PI and PII implants and 0.00 mm beneath the PBHA implants. Average posterior settling was 0.46 mm (range 0.00 to 2.00 mm) for the PI and PII implants and 0.03 mm (range 0.00 to 0.17 mm) for the PBHA implants. The percentage of soft tissue change at pagonion relative to the size of the implant was 83.0% (range 66.7% to 100.0%) for PI and PII and 86.8% (range 77.3% to 100.0%) for the PBHA implants. When PI or PII implants were used, younger patients had more resorption than older patients. Slightly more resorption was found with PI and PII implants when maxillary surgery was performed. The size of the PI or PII implants made no difference in the amount of bone resorption, although there was slightly less soft tissue change when larger implants were used. Males had slightly more bone resorption than did females. The bone resorption beneath the PI and PII implants occurred within the first 12 months postsurgery. It can be concluded from this study that PI and PII implants are acceptable materials for chin implants, but some resorption can be expected during the first 12 months postsurgery. The absence of detectable resorption and the excellent soft tissue change make PBHA an attractive alternative as a chin implant material, although it is technically more difficult to use.     

Transverse effects after surgically assisted rapid maxillary expansion in the midpalatal suture using computed tomography

Surgically assisted rapid maxillary expansion is the treatment of choice for correcting maxillary transverse deficiency in adults. Traditionally, the appliance for expansion is tooth-borne and tissue-tooth-borne devices (Hyrax and Haas). Although a number clinical and radiographic studies have evaluated the surgically assisted rapid maxillary expansion, only limited information is available to study the transverse movement of the midpalatal suture with computed tomography. Forty adult patients of both sexes, ranging in age from 18 to 38 years, with bilateral transverse maxillary deficiency were operated on. Twenty patients had Hyrax expander, and 20 had Haas expander. Under general anesthesia, subtotal Le Fort I osteotomy was performed including pterygomaxillary dysjunction. The width of the midpalatal suture opening was measured at the anterior edge of the midpalatal suture and at the junction of the midpalatal suture and palatal bones, using computed tomography in axial acquisition, obtained in the preoperative period and immediately after the end of expansion. A digital caliper was used to measure Haas and Hyrax distance on the central jackscrew preoperatively and postoperatively. The proportion between the midpalatal suture expansion and the amount of expansion on the jackscrew was evaluated. The mean of midpalatal suture opening and screw opening for Haas group was 5.19 and 8.78 mm, and for the Hyrax group, 5.85 and 8.51 mm, respectively. Both groups showed parallel-shaped separation of the midpalatal opening with no significant difference in the anterior and posterior portion. Midpalatal/jackscrews opening proportion was greater in the Hyrax group (69,2%) than in the Haas group (60%).     

Relocation of a malpositioned maxillary implant with piezoelectric osteotomies: a case report

Implant relocation is a new surgical technique for correcting the alignment of malpositioned implants by mobilizing them with the surrounding bone until the desired position is achieved. In this case report, a 25-year-old woman was treated for the malposition of an implant in the maxillary left canine site. The use of a piezoelectric scalpel permits narrow, precise, and safe osteotomies, thus preventing involvement of the soft tissue and producing better healing potential compared to burs or saws. The results suggest that inadequately axially inclined implants can be successfully reconfigured using segmental piezoelectric osteotomies.     

Evaluation of the three-dimensional soft tissue changes after anterior segmental maxillary osteotomy

The aim of this study was to assess the three-dimensional soft tissue changes following anterior segmental maxillary osteotomy, in terms of magnitude and direction in correlation to hard tissue changes, using cone beam computed tomography (CBCT). The study included 6 patients (age range 17-35 years) suffering from dental maxillary protrusion that required surgical correction by anterior segmental maxillary osteotomy. For each patient, preoperative and postoperative CBCT, photographs, and orthodontic casts were taken before and 6 months after operation to analyse soft tissue changes, in terms of magnitude and direction in correlation to hard tissue changes, using linear and angular measurements. Hard and soft tissue changes were only observed in the maxillary region, upper lip area and nasal tip. Soft tissue mean change included 53% backward displacement of the labrale superius in relation to bone displacement and 18.7% mean increase in the naso-labial angle. The highest correlation coefficient was obtained between the hard and soft tissue changes in the upper lip region. Anterior segmental maxillary osteotomy might be recommended as the treatment modality of choice in patients with maxillary or dento-alveolar protrusion, the technique is simple, safe, and postoperative complications are minimal.     

Surgical and orthodontic rapid palatal expansion in adults using Glassman's technique: retrospective study

In 1984, Glassman et al. described a conservative surgical method of separation of the midpalatal suture in which an osteotomy is done only at the lateral and anterior wall of the maxilla. Between 1991 and 1997, we have operated on 21 patients with maxillary transverse discrepancies using the method that they described. This gave good results in 20 patients. The other, who was operated on at the age of 38 years, developed a fracture of the alveolar process of the maxilla on one side because of ossification of the midpalatal suture. The surgically assisted rapid palatal expansion described by Glassman et al. is suitable for patients up to the age of 30. Older patients require additional surgical separation of the midpalatal suture.     

Surgically assisted rapid maxillary expansion in adults.

Twelve adults with maxillary width discrepancy of greater than 5 mm were treated by surgically assisted rapid maxillary expansion. The procedure consisted of bilateral zygomatic buttress and midpalatal osteotomies combined with the use of a tooth-borne orthopedic device postoperatively. Mean palatal expansion of 7.5 mm (range of 6 to 13 mm), measured in the first molar region, was achieved within 3 weeks in all patients. Expansion remained stable during the 12-month study period, with a mean relapse for the entire group of 0.88 +/- 0.48 mm. Morbidity was limited to mild postoperative discomfort. The results of this preliminary study indicated that surgically assisted rapid maxillary expansion is a safe, simple, and reliable procedure for achieving a permanent increase in skeletal maxillary width in adults. Further study is necessary to document the three-dimensional movements of the maxillary segments and long-term stability of the skeletal and dental changes.     

采用超声骨刀在局部麻醉下行外科辅助上颌骨快速扩弓术的临床应用

目的 探讨采用超声骨刀在局部麻醉下进行外科辅助上颌骨快速扩弓（SARME）手术的可行性。方法 选择14例上颌骨横向发育不足的患者（其中男性6例,女性8例）为研究对象,在局部麻醉下用超声骨刀行 SARME手术,手术方式采用腭中缝截骨术+侧方骨皮质切开术+双侧翼颌连接截骨术。采用问卷调查方式调查患者的术中感受。结果 所有患者的SARME手术均在门诊手术室采用局部麻醉完成,患者均耐受并配合手术。超声骨刀损伤小,可以精确截骨,术后反应小。问卷调查结果显示,术中没有或者仅感觉到轻度震动感的有8例（占 57.14%）;术中没有或仅感觉到轻度疼痛和牙齿酸痛的有12例（占85.71%）;对超声骨刀的声音无畏惧感或仅有轻度畏惧感的有 11例（占78.57%）。患者术前和术后6个月牙弓宽度的测量值显示手术扩弓的效果非常明显。结论 利用超声骨刀在局部麻醉下行SARME手术是可行的,但需要更多病例的实践和更长时间的随访。     

种植钉辅助上颌快速扩弓治疗年轻成人上颌牙弓狭窄的CBCT分析

目的 探讨种植钉辅助上颌快速扩弓治疗年轻成人上颌狭窄的效果.方法 样本包括15.5～28.0岁上颌骨性狭窄病例10例(男3例,女7例),平均年龄(20.1±5.4)岁.使用种植钉辅助上颌快速扩弓技术,分别于治疗前、扩弓后和保持3个月后拍摄CBCT,并对资料进行统计分析.结果 扩弓后腭中缝前部和后部分别增加3.49 mm和2.94 mm,后部腭中缝增量占扩弓器扩大量的47.9％,后部腭中缝增量占第一磨牙间宽度增量的52.3％.鼻腔宽度、上颌基骨和牙槽宽度扩弓后增加(P＜0.05),且保持三个月后增加量无明显改变.牙槽骨高度变化无统计学意义(P＞0.05).结论 种植钉辅助上颌快速扩弓能有效开展年轻成人腭中缝,矫正骨性牙弓狭窄,并减少牙支抗扩弓引起的副作用.     

Localized vertical maxillary ridge preservation using bone cores and a rotated palatal flap

The aim of vertical augmentation of the alveolar ridge is to restore resorbed alveolar ridges. This technique is critical to the placement of dental implants in a favorable position and the enhancement of restoration esthetics. The present report describes a technique for surgical preservation of the anterior maxillary process using maxillary bone from the surgical site and raising a soft tissue rotated palatal flap. Maxillary lateral incisor extraction and periapical surgery of the central incisors were first carried out. Two bone cores were harvested from the neighboring buccal vestibular region and placed in the sockets of the lateral maxillary incisors. After 3 months, implants were placed; 12 weeks later, the prosthetic restorations were cemented. There were no complications after 2 years of follow-up. This technique constitutes a viable approach for preserving the anterior sector alveolar ridge with the posterior placement of dental implants.     

冠向复位瓣联合结缔组织移植重建上颌种植义齿周围软组织缺损的临床研究

目的评价冠向复位瓣技术联合结缔组织移植术重建种植义齿修复后软组织缺损的临床效果。方法收集11例11颗上颌前牙区单颗种植义齿修复后存在软组织严重退缩影响美观的病例,所有患者从腭部获取游离结缔组织联合冠向复位瓣技术进行上皮下结缔组织移植术重建软组织。以手术后1年为基线,临床评估软组织愈合情况,种植义齿牙龈曲线、修复体与天然邻牙唇侧龈缘位置的协调性。结果11颗种植义齿术后红色美学明显改善。追踪观察1～4年,临床效果稳定。结论采用冠向复位瓣技术联合腭部游离结缔组织重建种植义齿修复后软组织缺损短期临床效果良好,其长期稳定性有待进一步研究。     

Unsplinted implants retaining maxillary overdentures with partial palatal coverage: report of 5 consecutive cases

PURPOSE: It is believed that maxillary dental implants must be splinted when used to retain removable overdenture prostheses in order to maintain osseointegration. This paper presents clinical cases to demonstrate that contemporary implants can function in an unsplinted manner to retain maxillary removable overdentures with partial palatal coverage. MATERIALS AND METHODS: Five consecutive patients were treated using a specific surgical and prosthodontic protocol. Twenty-five textured-surface implants were placed to retain overdenture prostheses in five patients, with a minimum of 4 implants per patient. These patients were followed for 12 to 48 months postloading. RESULTS: To date, none of the implants have lost osseointegration, and radiographic marginal bone levels are stable. Patients have been able to maintain soft tissue health around the unsplinted implants. The patients have verbally indicated that they are comfortable and that their maxillary overdentures function well. CONCLUSION: This preliminary report presents 5 consecutive cases in which unsplinted implants maintained osseointegration when used to retain removable overdenture prostheses with limited palatal coverage. It appears that unsplinted maxillary implants can be used to retain a maxillary overdenture.     

A comparison of dental and dentoalveolar changes between rapid palatal expansion and nickel-titanium palatal expansion appliances.

A tandem-loop nickel titanium temperature-activated palatal expansion appliance was developed that produces light, continuous pressure on the midpalatal suture and requires little patient cooperation or laboratory work. The purpose of this study was to compare the effectiveness of the nickel titanium palatal expansion appliance with that of a rapid palatal expansion appliance. The study sample comprised 25 patients who required palatal expansion as part of their orthodontic treatment. The sample was divided into 2 groups, with 13 patients in the nickel titanium group and 12 patients in the rapid palatal expansion group. Study models were taken before treatment and at the end of the retention period after expansion. Intermolar width, palatal width, palatal depth, alveolar tipping, molar tipping, and molar rotation were analyzed. In addition, occlusal radiographs were obtained before and 2 weeks after expansion to evaluate for sutural separation by the appliances. Results showed significant increases in midpalatal sutural separation, tipping of the alveolus, and tipping of the molars after expansion in both groups. However, greater midpalatal sutural separation was found in the rapid palatal expansion group and greater molar rotation was found in the nickel titanium group. Stepwise multiple regression analysis showed that alveolar tipping, palatal width change, and molar tipping are the best predictors of intermolar width change in the rapid palatal expansion group. Radiographic evidence of midpalatal sutural separation was less obvious in the nickel titanium group. These results suggest that both the nickel titanium and the rapid palatal expansion appliances are capable of expanding the maxillary dentition and alveolar process and are equally capable of correcting posterior crossbites. In the current study, the rapid palatal expander widened the palate more reliably, whereas the nickel titanium expander tipped the molars buccally to a greater extent and caused more distal molar rotation. The clinician's choice of expander will depend on his or her initial diagnosis and treatment goals.     

Wound healing after multisegmental le fort i osteotomy and transection of the descending palatine vessels

Vascular ischemia has been associated with improper soft tissue flap design, stretching of the palatal vascular pedicle, bony segmentation, transection of the descending palatal vessels, or hypotension. This study examined Le Fort I osteotomy wound healing after some of these surgical maneuvers. Clinically analogous four-segment Le Fort I osteotomies were accomplished through circumvestibular incisions in nine adult rhesus monkeys and the animals were killed at 0, 3, 7, 14, and 28 days after surgery. Revascularization and bone healing were studied by microangiographic and histologic techniques. The findings indicated that the palatal mucosa or labial-buccal gingiva and mucosa provide adequate nutrient pedicles for Le Fort I osteotomies accomplished through a circumvestibular type incision. It was concluded that segmentalization, stretching of the vascular pedicles, or transection of the descending palatine vessels have only transitory discernible effects on revascularization and bone healing.     

Wound healing associated with segmental total maxillary osteotomy

A technique that maintains dual soft tissue pedicles to the palatal and labiobuccal areas in segmental total maxillary osteotomy was studied with respect to the effects on osseous revascularization and healing. Single-stage four-segment total maxillary osteotomies were performed by this method in five adult male rhesus monkeys. The animals were killed at intervals from immediately to 28 days after surgery. Histologic examination of the maxillae revealed that this technique is sufficient to support total maxillary osteotomy through 28 days. The soft tissue flap provided adequate blood supply to the anterior maxillary segment. All bony segments were mobilized, with only transient effects on bone healing and viability. The marginal osteonecrosis observed did not appear to be progressive. The effects of this procedure on the pulp are not clear.