Postoperative effects of anterior nasal spine bone harvesting on overall nasal shape

Metric evaluation of the anterior nasal spine to estimate sex and population group in South African individuals

INTRODUCTION

The anterior nasal spine is a pointed, midline projection of the maxilla. This bony structure dictates the overlying soft tissues providing the phenotypic features of the nose and upper lip and determines the differences in the mid-face morphology. Little data is available on the metric features of the Anterior nasal spine (ANS). This study aimed to perform metric evaluations of the ANS of white and black South African males and females to ascertain if morphological variations exist and if the differences are viable for the use in sex and population identification.

MATERIALS AND METHODS

The sample included 100 CBCT images for each population and sex group. Linear and angular measurements of the ANS were recorded in both the sagittal and axial planes.

RESULTS

Classification decision trees (pruned) were fitted to ascertain the relationship between population group, sex and the ANS measurements including and excluding age. For population group, all the ANS measurements were statistically significant for females but in males, all the ANS measurements were significant when performed individually. However, when fitted to the classification tree, Sagittal 2 did not show any statistical significance. When considering sex, only 2 of the ANS measurements (Sagittal 2 and Axial 1) were found to be significant. The results did not differ significantly when comparing the decision trees including and excluding age.

CONCLUSIONS

White South African individuals presented with a longer ANS that produced a more acute angle whereas black South African individuals presented with a shorter ANS and a more obtuse angle. Additionally, males presented with a longer ANS compared to females. ANS measurements were found to be more relevant for population discernment than for sex.

Anatomical Patterns of the Nasopalatine Canal and Incisive Foramen in an African Setting: A Cross-Sectional Study

Study Design: Descriptive cross-sectional. Objective: To determine the morphology and morphometry of the nasopalatine canal (NPC) and incisive foramen (IF) in an African population. Methods: Measurements of the NPC and the IF were carried out on 150 Cone-Beam computed tomography (CBCT) scans. The maxillary bone thickness anterior to the NPC was measured at 3 levels. Independent t-test and Chi-square test were performed to determine the presence of sexual dimorphism. Results: The presence of one Stenson's foramen was most prevalent. The mean length of NPC was 13.21 ± 3.25 mm with significantly longer canals in males. The most prevalent shape of NPC was cylindrical in sagittal view and a single canal in coronal view. The mean angulation of NPC was 118.42° to the horizontal plane. The average dimensions of the IF were 3.53 mm and 3.07 mm in the anteroposterior and mediolateral diameter, respectively, while the most common shape was round. The anterior maxillary bone was thicker in males and generally reduced in thickness from the anterior nasal spine superiorly towards the alveolar crest inferiorly. Conclusion: This study highlights the anatomical characteristics of the NPC and IF, with significant sexual dimorphism observed regarding the number of Stenson's foramina, length of NPC, shapes of the NPC and IF, as well as alveolar bone thickness anterior to NPC.

Extraction of high inverted mesiodentes via the labial, palatal and subperiostal intranasal approach：A clinical prospective study

The aim of this study is to provide criteria for the choice of the surgical approach for extraction of high inverted mesiodens. The operation statistics, life quality of postoperative patients, and the operative injury/recovery were compared and analysed. The laser Doppler blood flowmetry, laser speckle contrast imaging, and electric pulp testing were explored to detect the postoperative pulp and gingiva blood supply of adjacent teeth. For the clinician's primary concerns, the surgical time, the volume of osteotomy, and the amount of bleeding in the labial approach group (The p values are 0.0001, <0.0001, and 0.0131, respectively.) and intranasal approach group (All p values were <0.0001.) were significantly less than that in the palatal approach group. However, from the patient's perspective, the postoperative swelling in the labial approach was far more than that in the intranasal approach group (p =0.0044), with unsurprisingly lower satisfaction (p <0.0001). There were no significant differences in pulp and gingival blood supply of adjacent teeth and jaw development. Trauma was manageable in all patients. Within the limitations of the study it seems that extraction of mesiodens by the intranasal approach achieves a delicate balance between reducing surgical trauma and optimizing postoperative recovery.

Facts to Consider in Developing Materials That Emulate the Upper Jawbone: A Microarchitecture Study Showing Unique Characteristics at Four Different Sites

The maxilla is generally acknowledged as being more trabecular than the mandible. Allograft currently available for use in the maxillofacial region is harvested from the hip and long bones, irrespective of their local characteristics, and grafted onto the jawbones. Other alternative are autograft or commercially available bone substitutes. Due to their inherent differences, an in-depth understanding of the bone microarchitecture is important to develop the most compatible graft for use at the maxilla. This cross-sectional study aimed to determine the microstructures of bone harvested from different sites of the maxilla, to be used for standard setting. Forty-nine specimens from seven human cadavers were harvested from the zygomatic buttress, anterior maxillary sinus wall, anterior nasal spine and anterior palate. Each bone block, measuring of 10 mm × 5 mm, was harvested using rotary instruments. Bone analysis was performed following micro-computed tomography to obtain trabecular number (Tb.N), trabecular separation (Tb.Sp), trabecular thickness (Tb.Th), and bone volume fraction (BV/TV). There were site-related differences, with BV/TV that ranged between 37.38% and 85.83%. The Tb.N was the lowest at the palate (1.12 (mm−1)) and highest at the anterior maxillary sinus wall (1.41 (mm−1)) region. The palate, however, had the highest trabecular separation value (Tb.Sp) at 0.47 mm. The TB.Th was the lowest at the anterior nasal spine (0.34 mm) but both the zygoma and anterior maxillary sinus regions shared the highest Tb.Th (0.44 mm). Except for having the lowest Th.Sp (0.35 mm), the anterior maxillary sinus wall consistently showed higher values together with the zygomatic buttress in all other parameters. Concurring with current clinical practice of harvesting autograft from the zygomatic buttress and anterior maxillary sinus wall, their bony characteristic serve as the microarchitecture standard to adopt when developing new bone graft materials for use in the maxilla.

Reliability of Anterior Nasal Spine as a Reference Point After LeFort I Surgery Using Three-Dimensional Analysis

ABSTRACT

To evaluate the stability of maxilla following orthognathic surgery, it is necessary to consider the positional change of various landmarks according to bone remodeling of the maxilla. This study aimed to evaluate the stability of the anterior nasal spine (ANS) as a reliable landmark after orthognathic surgery. Forty-seven patients with skeletal class III malocclusion who underwent bimaxillary orthognathic surgery were included. Skeletal changes were measured using cone-beam computerized tomography at 3 time points: preoperative (T0), 1-month postoperative (T1), and 12-month postoperative (T2). Linear changes of the 6 landmark points of the maxilla were measured in 3 directions: anteroposterior, vertical, and transverse. The data were analyzed with paired t tests, independent t tests, and multiple regression analysis. At 12-month postoperatively, the ANS showed mean (standard deviation) 1.23 (1.07) mm posterior movement (P = 0.00), while other landmarks did not show positional changes, implying bony resorption of ANS. Multiple regression test showed surgical forward movements of ANS (T1-0) affect the postoperative backward changes (β = -.05, P < 0.05). There was a negative correlation between the surgical movement and postoperative change of ANS by Pearson correlation test (r = -0.38, P < 0.05). The ANS is not a reliable measurement point in three-dimensional superimposition after orthognathic surgery. Therefore, in studying the stability and positional change pattern after LeFort I surgery, it is not recommended to use ANS as a reference point, as changes can occur in the measurement point itself.

Preclinical and Clinical Applications of Biomaterials in the Enhancement of Wound Healing in Oral Surgery: An Overview of the Available Reviews

Oral surgery has undergone dramatic developments in recent years due to the use of biomaterials. The aim of the present review is to provide a general overview of the current biomaterials used in oral surgery and to comprehensively outline their impact on post-operative wound healing. A search in Medline was performed, including hand searching. Combinations of searching terms and several criteria were applied for study identification, selection, and inclusion. The literature was searched for reviews published up to July 2020. Reviews evaluating the clinical and histological effects of biomaterials on post-operative wound healing in oral surgical procedures were included. Review selection was performed by two independent reviewers. Disagreements were resolved by a third reviewer, and 41 reviews were included in the final selection. The selected papers covered a wide range of biomaterials such as stem cells, bone grafts, and growth factors. Bioengineering and biomaterials development represent one of the most promising perspectives for the future of oral surgery. In particular, stem cells and growth factors are polarizing the focus of this ever-evolving field, continuously improving standard surgical techniques, and granting access to new approaches.

Updated Dynamics of Rhinoplasty: A Review of the Literature and Comprehensive List of the Findings

BACKGROUND

The cardinal reason accounting for the complexity of rhinoplasty is that each maneuver during this operation has both intended and unintended effects. The purpose of this report is to review the literature and update the dynamics of rhinoplasty.

METHODS

PubMed searches were conducted for "rhinoplasty dynamics" as well for keywords associated with each specific rhinoplasty maneuver. Titles were evaluated for relevance, and duplicates were consolidated with years of publication 1991 to 2019. Article types include case series (retrospective and prospective), cohort studies, and review articles.

RESULTS

Beginning with the radix, its reduction apparently elongates the nose and widens the intercanthal space, while radix augmentation creates the opposite illusions. In a similar manner, dorsal hump reduction widens both the nose and intercanthal space. Nasal tip dynamics focus on the aftermath of changes to tip projection, width, and rotational position. Resection of the upper lateral cartilages can cephalically rotate the tip and reduce tip width. Manipulation of the footplates of the medial crura primarily influences the columella but can also affect tip projection. Placement of a columellar strut firmly establishes tip position. Placement of alar rim grafts advances the ala caudally, widens the nostrils, and elongates the short nostril. Alar base reduction can create the illusion of increased tip projection. Augmentation and reduction in the anterior nasal spine influence tip projection, upper lip length, and the nasolabial angle.

CONCLUSIONS

As rhinoplasty techniques continue to evolve, surgeons undertaking this operation must continue to reassess the dynamics of various maneuvers.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Bone grafting materials in dentoalveolar reconstruction: A comprehensive review

Bone deficits of the jaws are often attributed to accidents, surgical removal of benign lesions or malignant neoplasms, congenital abnormalities, periodontal inflammation, tooth abscess or extraction and finally jaw atrophy due to advanced age or general disease. These bone defects require rehabilitation for a variety of reasons, e.g. maintaining the normal anatomic outline, eliminating empty space, aesthetic restoration and placing dental implants. Today, several techniques have been developed to eliminate these bone deformities including bone grafting, guided bone regeneration, distraction osteogenesis, use of growth factors and stem cells. Bone grafts consist of materials of natural or synthetic origin, implanted into the bone defect site, documented to possess bone healing properties. Currently, a variety of bone restorative materials with different characteristics are available, possesing different properties. Despite years of effort the 'perfect' bone reconstruction material has not yet been developed, a further effort is required to make this objective feasible. The aim of this article is to provide a contemporary and comprehensive overview of the grafting materials that can be applied in dentoalveolar reconstruction, discussing their properties, advantages and disadvantages, enlightening the present and the future perspectives in the field of bone regeneration.

Modified maxillary vestibular approach with subperiostal intranasal dissection for surgical extractions of mesiodentes impacted in the floor of the nasal cavity

INTRODUCTION

Impacted mesiodentes in the inverted position may interfere with the base of the nasal cavity or the nasal septum. They can rarely erupt into the nose as well. Traditionally they are extracted via intraoral approaches (transpalatal or vestibular). Also, an endoscopically assisted transnasal approach can be used. In this paper, the authors are the first to present a group of patients suffering from impacted mesiodentes who have been surgically treated using a modified maxillary vestibular approach with subperiostal intranasal dissection.

MATERIAL AND METHOD

The prospective study was completed in the time period 12/2013-6/2017. The inclusion criteria were: 1. Mesiodens impacted in the inverted position extending to the base of the nasal cavity or into the nasal septum without concomitant pathological lesion and without eruption into the nasal cavity. 2. Localization of the mesiodens at the level of or dorsally to the roots of the upper middle incisors in the sagittal plane or ventrally to the roots of these teeth, but with the crown extending significantly posteriorly to the base of the nasal cavity.3. Indication for extraction because of clinical or orthodontic reasons.

RESULTS

In total, 9 patients were enrolled into the group. In these patients, surgical extractions of 9 mesiodentes were performed using the alternative approach described above. All extractions were done according to a uniform surgical protocol. The mean age of the patients was 11.7 ± 3.1 years (age range 7-17 years). The crown's most cranial point exceeded the bone of the nasal cavity on average by2.0 ± 1.4 mm (in the range 0-5 mm). 8 mesiodentes were conical, 1 was tuberculate. Surgical procedure and postoperative healing were always without any complications.

CONCLUSION

For the removal of midline supernumerary teeth, the modified maxillary vestibular approach with subperiostal intranasal dissection in comparison to the intraoral palatal approach provides less postoperative morbidity and a lower risk of complications (smaller surgical wound, minimal exposure of maxilla, minimal bone loss, reduced risk of damage to the roots of the upper incisors, lower risk of damage to the nasopalatine neurovascular bundle, good visibility in the surgical field, easier surgery, and finally no need of postoperative palatal splint). For oral and maxillofacial surgeons the presented technique represents a more traditional way of surgical tooth extraction than the endoscopically assisted transnasal approach.

Alternative intraoral donor sites to the chin and mandibular body-ramus

Background

Provide a review of alternative intraoral donor sites to the chin and body-ramus of the mandible that bring fewer complications and that may be used to regenerate small and medium defects.

Material and Methods

A review was conducted using the search engine PUBMED and looking manually into scientific journals.

Results

From the 35 articles included, 6 corresponded to the coronoids, 3 corresponded to the zygomatic body, 5 corresponded to the anterior maxillary sinus wall, 3 corresponded to the zygomatic alveolar process, 2 corresponded to the incisive fossa, 2 corresponded to the anterior nasal spine, 2 corresponded to the palatal region, 5 corresponded to the tuberosity, and 7 corresponded to the palatal and mandibular tori.

Conclusions

Although there are few complications described when using alternative intraoral donor sites, the main problem with these types of grafts is their scarce bone volume, with only the zygomatic body, anterior sinus wall, and palate sites being able to be used in medium defects. More clinical trials are necessary in order to evaluate the behavior of the alternative donor sites over time. Key words:Grafting, autologous bone, autografts, mandible, maxilla, palate hard, zygoma.

Computer-designed surgical guide template compared with free-hand operation for mesiodens extraction in premaxilla using "trapdoor" method

The aim of this study was to introduce a novel method of mesiodens extraction using a vascularized pedicled bone flap by piezosurgery and to compare the differences between a computer-aided design surgical guide template and free-hand operation.A total of 8 patients with mesiodens, 4 with a surgical guide (group I), and 4 without it (group II) were included in the study. The surgical design was to construct a trapdoor pedicle on the superior mucoperiosteal attachment with application of piezosurgery. The bone lid was repositioned after mesiodens extraction. Group I patients underwent surgeries based on the preoperative planning with surgical guide templates, while group II patients underwent free-hand operation. The outcome variables were success rate, intraoperative time, anterior nasal spine (ANS) position, changes of nasolabial angle (NLA), and major complications. Data from the 2 groups were compared by SPSS 17.0, using Wilcoxon test.The operative time was significantly shorter in group I patients. All the mesiodentes were extracted successfully and no obvious differences of preoperative and postoperative ANS position and NLA value were found in both groups. The patients were all recovered uneventfully.Surgical guide templates can enhance clinical accuracy and reduce operative time by facilitating accurate osteotomies.

Frequency of bone graft in implant surgery

BACKGROUND

Implant surgery has become popular with the advance of surgical techniques such as sinus lifting, guided bone regeneration, and block bone graft. However, there were no data about the frequency of bone graft during implant surgery. The purpose of this study was to report the frequency and types of bone graft depending on dental implant patients' profile to complement the database regarding implant surgery.

METHODS

The implant operations had been performed from January 2006 to October 2014. The upper and lower jaws were divided into six sextants. A total of 792 sextants were included in this study. Patient information including sex, age, sites, bone graft, and types of bone were investigated.

RESULTS

A total of 1512 implants had been placed. Male and female sextants were 421 and 371, respectively (M:F = 1:0.88). Average age was 54.3 (ranging from 20 to 88 years old). Implants were placed in the posterior maxilla (322 sextants, 40.7 %), posterior mandible (286 sextants, 36.1 %), anterior maxilla (127 sextants, 16.1 %), and anterior mandible (57 sextants, 7.2 %). Bone graft was performed in 50.3 % of the sextants. Among the bone grafted sites, sinus lifting with lateral approach (22.1 %) and guided bone regeneration (22.7 %) were performed most frequently.

CONCLUSIONS

Bone graft in implant surgery was necessary to augment defects. More than half of the sextants needed bone graft for implant installation.

The anterior maxilla as a potential source of bone grafts: a morphometric cone beam computed tomography analysis of different anatomical areas

The aim of this research was to use cone beam computed tomography (CBCT) to analyze the volume, density, and morphology of the bone available in the anterior region of the maxilla, in order to investigate its potential as a source of bone grafts. Three independent zones were evaluated: the palatine process of the maxilla (PPM), anterior nasal spine (ANS), and subnasal bone (SN). The latter was analyzed bilaterally (SNR, SNL). One hundred CBCT scans were evaluated. The morphometric analysis comprised volumetric and subsequent automatic density calculations, as well as linear measurements. Potential correlations among these parameters, including demographic characteristics, were investigated. The study comprised 52 women and 48 men (mean age 49.6±14.5 years). The calculated bone volume averaged 2.41±0.72cm(3) for PPM, 0.46±0.16cm(3) for ANS, 0.58±0.2cm(3) for SNR, and 0.57±0.21cm(3) for SNL. The anterior region of the maxilla can provide a considerable amount of bone volume from different anatomical zones and should be regarded as a potential donor site for the regeneration of maxillary atrophic bones. Further investigation is required before these findings can be applied in the routine clinical setting.

Complications in the use of the mandibular body, ramus and symphysis as donor sites in bone graft surgery. A systematic review

Background

To develop a systematic review by assessing and comparing the different complications that occurs in bone graft surgery using the mandibular body, ramus and symphysis as donor sites.

Material and Methods

In order to respond to the following question, a systematic review was developed: does the use of intraoral mandibular body and ramus as donor sites in bone graft surgery, produce fewer and less severe complications in comparison to the use of the mandibular symphysis in patients that present bone resorption that needs augmentation using autologous grafts? The review was carried out between January 1990 and 2015, during which only clinical essays with a minimum follow-up period of six months were included.

Results

The initial search yielded a total of 2912 articles, of which 6 were finally selected. In total, 259 graft surgeries were performed; 118 using the mandibular body and ramus as donor sites, and 141, the symphysis. The most frequent complications that arose when using the mandibular symphysis were temporary sensory alterations in the anterior teeth (33.87%), followed by sensory alterations of the skin and mucosa (18.57%). As for the mandibular body and ramus donor sites, the most frequent complications relate to temporary sensory alterations of the mucosa (8.19%) and to minor postoperative bleeding (6.55%).

Conclusions

The analyzed results show a higher prevalence and severity of complications when using mandibular symphysis bone grafts, producing more discomfort for the patient. Therefore, it would be advisable to perform further clinical essays due to the lack of studies found.

Key words:Alveolar ridge augmentation, autogenous bone, mandibular bone grafts, chin, mandibular symphysis, mandibular ramus.