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Purpose: The present study investigated the effect of piezoelectric sutural ostectomies on accelerated bone-borne sutural expansion., Materials and Methods: Sixteen male New Zealand white rabbits (20 to 24 weeks old) were randomly divided into 4 experimental groups (n = 4): group 1, conventional rapid sutural expansion; group 2, accelerated sutural expansion; group 3, accelerated sutural expansion with continuous ostectomy; and group 4, accelerated sutural expansion with discontinuous ostectomy. All sutural ostectomies were performed using a piezoelectric instrument (Woodpecker DTE, DS-II, Guangxi, China) before expander application with the rabbits under anesthesia. Modified hyrax expanders were placed across the midsagittal sutures of the rabbits and secured with miniscrew implants located bilaterally in the frontal bone. The hyrax expanders were activated 0.5 mm/day for 12 days (group 1) or with a 2.5-mm initial expansion, followed by 0.5 mm/day for 7 days (groups 2 to 4). After 6 weeks of retention, the bone volume fraction, sutural separation, and new bone formation were evaluated using micro-computed tomography and histomorphometry. Statistical analysis was performed using Kruskal-Wallis and Mann-Whitney U tests and Spearman's rho correlation (P < .05)., Results: Ranking of the median sutural separation was as follows: group 1, 3.05 mm; group 2, 3.97 mm; group 4, 4.78 mm; and group 3, 5.66 mm. The least and most bone formation were observed in groups 1 (63.63%) and 3 (75.93%), respectively. Spearman's correlation showed a strong, positive, and significant correlation (r = 0.932; P < .01) between the new sutural bone formation and amount of sutural separation., Conclusions: Piezoelectric sutural ostectomies increased the rate of sutural separation and promoted new sutural bone formation/osteogenesis. Continuous ostectomy gave better results than discontinuous ostectomy., (Copyright © 2017. Published by Elsevier Inc.)

Purpose: The aim of this study was to compare the efficacy of hyperbaric oxygen and systemic ozone, used separately and in combination, on the healing of bone defects., Material and Methods: Sixty male Wistar rats were divided into 4 groups (n = 15) according to treatment (control, hyperbaric oxygen [HBO], ozone [O], and HBO plus O [HBO-O]) and divided further into 3 subgroups according to day of sacrifice (postsurgical days 5, 15, and 30). Surgery was performed under general anesthesia to create a critical-size bone defect (5 mm in diameter) in the cranium. After sacrifice, microtomographic images of all samples were recorded, and histomorphometric analysis was performed., Results: Histologic and radiologic measurements showed that the values of all experimental groups were higher than those of the control group. Histologic scores for all experimental groups were statistically higher than those for the control group day 30 (O, P = .045; HBO, P = .049; HBO-O, P = .042). Histologic scores also were statistically higher for the HBO group on day 5 (P = .045) and day 15 (P = .009) compared with the control group. Microtomographic scores were higher for the experimental groups than for the control group, with statistically significant differences for group O on day 5 (P = .033) and day 30 (P = .0045) and for group HBO on day 15 (P = .005). Histologic and radiologic analyses showed positive correlations., Conclusion: Within the limitations of this study, the use of hyperbaric oxygen and ozone, separately and in combination, were shown to be effective in increasing bone healing. Combined usage was no more effective in stimulating bone healing than separate usage., (Copyright © 2015 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Purpose: The previous decade has witnessed increasing emphasis on the technique of trans-sutural distraction osteogenesis (TSDO), a new and challenging procedure to reconstruct deficiencies in craniomaxillofacial bone. The purpose of this study was to determine if locally administered recombinant human bone morphogenetic protein-2 (BMP-2)/Poly(lactic-co-glycolic acid)/Fibrin sealant and recombinant human osteoprotegerin recombinant OPG fusion protein improves osteoblastogenesis and new bone formation by TSDO., Materials and Methods: Thirty-two dogs were divided into 4 groups: control, BMP-2, OPG, or BMP-2 plus OPG. Two dogs from each group were sacrificed at 1, 2, 4, and 6 weeks after initiating the DO protocol. Immunohistochemical, histomorphometric, and electron microscopic assessments were performed to investigate the effects of BMP-2 or OPG induced by TSDO., Results: The animals demonstrated significant overgrowth of the maxilla (control, 19.5 ± 2.61 mm; BMP-2, 19.9 ± 1.47 mm; OPG, 18.3 ± 1.2 mm; BMP-2 + OPG, 20.5 ± 2.65 mm). Histologically, the palatine suture widened dramatically within 2 weeks after distraction. Osteoblast number, trabecular thickness, content of alkaline phosphatase, and integrated optical density of BMP-2 increased obviously in the BMP-2 + OPG group (P < .05)., Conclusions: TSDO in growing dogs is a safe, well-tolerated technology. The study found that OPG alone did not improve bone regeneration, but that it acted synergistically with BMP-2 to increase recruitment of mesenchymal stem cells and led to a significant enhancement of bone formation and healing. The temporal pattern of BMP-2 expression is consistent with a role in the regulation of mechanical and biological interventions designed to promote bone regeneration., (Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.)

Purpose: We present our experience using modified Hyrax devices for treating transverse deficiencies of the maxilla in adult patients with periodontal pathology or insufficient tooth anchorage. The surgical technique, clinical indications, and results are discussed., Materials and Methods: Eight adult patients (6 females, 2 males) requiring maxillary expansion were studied prospectively between July 2002 and July 2007. All the patients had periodontal pathology or insufficient tooth anchorage preventing the use of conventional Hyrax devices. Patients underwent surgically assisted rapid maxillary expansion with the use of custom-made modified Hyrax devices (bone-borne or tooth-bone-borne devices). Patients received preoperatively (T1), at the end of distraction (T2), at removal of the expansion device (T3), and 12 months after surgery (T4) lateral and posterior anterior cephalograms and study models to measure the width of the anterior and posterior dental arches with a digital sliding calliper., Results: Mean age was 28.5 years (range, 18-45 years). A significant widening of the anterior (6.3 +/- 1.6 mm) and posterior (7.1 +/- 1.2 mm) dental arches was demonstrated. No significant differences were found when comparing T3 with T4 measures. No significant complications were found., Conclusion: The results indicated that maxillary expansion with custom-made devices in adults was an easy, affordable, predictable and stable technique without significant complications in patients who suffer periodontal pathology or patients without enough dental support., (Copyright 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Purpose: This study was conducted to assess a conservative technique for surgically assisted palatine expansion (SAPE) done under local anesthesia and conscious sedation in adults. Dental inclination, uniformity of expansion, and satisfaction of orthodontist were evaluated., Patients and Methods: Twenty-seven consecutive patients, ranging in age from 25 to 42 years, underwent SAPE under local anesthesia. The surgical procedure involved osteotomy of the lateral wall of the maxilla, from the maxillary tuberosity to the nasal cavity, with the nasal septum and the ptyerigoid plates left intact. Cast models were obtained before surgery and 1 year after surgery. Cuspid inclinations were assessed, with intercanine distance in 2 points, the incisal and cervical borders, measured before and after surgery. Molar inclination was obtained by measuring intermolar distance at the cervical margin and occlusal table. The results were statistically analyzed by analysis of variance. A questionnaire with 4 questions was addressed to the orthodontists to evaluate the level of satisfaction with the procedure., Results: Cuspid and molar inclination occurred, but there was no statistically significant difference (P < .05) in dental inclination before and after surgery. The expansion was greater at the molar level than at the canine level, but this difference also was not statistically significant (P > .05). According to the questionnaire, 100% of the procedures allowed the expansion, 100% of the orthodontists were satisfied, and 68.75% observed dental inclination, but this inclination was not excessive in 100% of the cases., Conclusions: The proposed technique is a safe, predictable, and reliable method for SAPE in adult patients. Although ptyerigoid plate and nasal septum fractures were not performed, the maxillary bone exhibited uniform expansion. Dental inclination was not significant, either clinically or during cast model analysis. Orthodontists could achieve treatment objectives with this surgical procedure.

Purpose: This study was designed to investigate the effects of artificial mechanical separation of the circummaxillary sutures on craniofacial growth in growing rats., Materials and Methods: Twenty 4-week-old Wistar strain male rats were divided equally into experimental and control groups. In the experimental group, 4 holes were made on the maxillary and temporary bones, and expansion appliances were placed into the holes for sutural separation bilaterally. The operated control group underwent sham surgery only. Lateral and dorsoventral cephalograms were taken of the animals every 2 weeks from age 4 to 12 weeks. Linear and angular measurements on the lateral cephalograms were analyzed and subjected to statistical treatment with Student's t-test. All animals were killed for histologic examination 8 weeks after the initiation of the experiment., Results: Nasomaxillary growth and the forward displacement were significantly larger in the experimental group than in the controls (P <.01). New bone formation was clearly observed in the (mechanically separated) sutural space in association with normal healing of the sutural structures., Conclusions: These findings show that mechanical separation of the circummaxillary sutures, as a new orthopedic approach, accelerated nasomaxillary growth, in this experimental model., (Copyright 2002 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 60:667-675, 2002)

Purpose: In orthognathic surgery, rigid fixation is routinely used to hold together bone fragments that may experience heavy force from attached masticatory muscles. Internal fixation plates are assumed to hold bony parts rigidly, but the mobility at such sites subjected to normal masticatory function has not been measured. The purpose of this study was to investigate in vivo the degree to which a linear plate immobilizes separated bones, specifically sutures., Materials and Methods: Three female miniature pigs (Sus scrofa) had 1.3-mm Synthes titanium plates placed across the suture in the zygomatic arch. Foil strain gauges were used to record load deformation in the zygomatic and squamosal (temporal) bones and across the vertical and horizontal parts of the suture. Strain was recorded in vivo during mastication and in anesthetized pigs with electrical stimulation of masticatory muscles., Results: Strain at the suture was not reduced from normal levels. The plate induced increases in strain within the bones, but the changes were slight., Conclusion: The results indicate that linear "rigid fixation" does not immobilize sutures.

Purpose: This study investigated the ability to use titanium screws to provide stable skeletal points in the growing craniofacial region of the rabbit for suture expansion. These screws provided sites for direct application of external forces to alter growth and anatomic form., Material and Methods: Twenty-one rabbits (30 days old) were divided into three groups: control (n = 9), experimental (n = 9, and sham (n = 3). Four four-holed AO/ASIF commercially pure titanium craniofacial plates were contoured into an L-shape with a 90 degree angle at the midpoint. The plates were placed bilaterally in the frontal and nasal bone sites and secured with 2.0-mm diameter, 4-mm long, commercially pure titanium screws in both the sham and experimental groups. After 4 week of healing, a spring mechanism with a distraction force of 55 g was activated between ipsilateral plates and across the frontonasal sutures bilaterally in the experimental group for 5 weeks. No force was applied between the plates in the sham group. A preliminary evaluation of the bone-implant interface and the changes in the suture was done histologically. Morphologic changes were measured using cephalometric radiographs and direct anatomic measurements., Results: The experimental group showed a significant increase in growth across the frontonasal suture in comparison with the sham group (P < .05). In addition, an increase in the length of the nasal and frontal bones in the expanded group was observed in comparison with the control and sham groups (P < .05). Histologically, a mixture of woven and lamellar bone was seen in the suture region and lamellar bone was seen in the screw-bone interface., Conclusion: This study indicates that titanium screws in the developing rabbit skull can provide stable sites for the direct application of external forces, producing secondary changes in skeletal morphology. This laboratory models provides a useful system for the further study of growth modification using such external mechanical forces.

The results of surgically assisted rapid maxillary expansion by opening of the midpalatal suture in 25 patients are reported. Osteotomy of the lateral wall of the maxilla combined with pterygomaxillary dysjunction and midpalatal suture separation allowed for successful rapid maxillary expansion in 23 patients. The two patients who did not respond to treatment were found to have unusually thick midpalatal sutures, which were successfully expanded after the midpalatal sutures were osteotomized.