Intermaxillary fixation screws and tooth damage

Comparison between Erich arch bars and intermaxillary screws in maxillofacial fractures involving the dental occlusion: a meta-analysis

This systematic review aimed to compare the Erich arch bars (EABs) with intermaxillary fixation (IMF) screws in maxillofacial fractures involving dental occlusion on perioperative parameters. Four electronic databases were searched: MedLine (Pubmed), Web of Science, VHL, and Cochrane Library. Inclusion criteria comprised clinical trials comparing the two IMF methods, assessing at least one of the outcomes: occlusal stability, oral hygiene, quality of life, time to apply and remove IMF appliances, and complications. Risk of bias was evaluated through the Cochrane risk of bias tool. Fifteen papers were included in the qualitative analysis and 12 of those in the meta-analysis. Times for EABs application (mean difference (MD) 46.83; 95% confidence interval (CI): 30.63-63.02) and removal (MD 22.89; 95% CI 14.61-31.17) were longer compared with IMF screws. There is higher risk of glove perforation (risk ratio (RR) 3.81; 95% CI 2.41-6.04) and lower risk of iatrogenic injuries (RR 0.21; 95% CI 0.09-0.48) when placing EABs compared with IMF screws. No significant differences in plaque index were found (MD 1.07; 95% CI -0.17 to 2.31). The quality of this evidence ranged from very low to low and was mainly compromised by risk of bias assessment. Further studies are necessary to evaluate transurgical IMF stability and postoperative occlusal quality and quality of life when comparing EABs with IMF screws.

Are Bondable Buttons a Better Option than Intermaxillary Fixation Screws for Achieving Maxillomandibular Fixation? A Prospective Randomized Clinical Study

Aim

The aim of this study was to identify a better option in achieving maxillomandibular fixation (MMF) comparing bondable buttons and Maxillomandibular Fixation screws in achieving Maxillomandibular Fixation.

Patients and Methods

In this randomized clinical trial, study sample was derived from the population of patients who reported with minimally displaced mandibular fractures and who required Maxillomandibular Fixation. The patients were divided into two groups. In Group I (n = 20), Maxillomandibular Fixation was done with Maxillomandibular Fixation screws; on the other hand, in Group II (n = 20), bondable buttons were used. In both the groups the patients were analyzed for the time duration required in minutes for securing and removal of Maxillomandibular Fixation, plaque accumulation and postoperative stability. Plaque accumulation was evaluated using TURESKY-GILMORE-GLICKMAN modification of the Quigley-Hein plaque index. The complications encountered during and after the surgery were also analyzed.

Results

The plaque accumulation and time required for placement and removal in group I were more as compared to group II. In Group I, there were more complications as compared to Group II such as tooth root damage, screw loosening, screw breakage and infection.

Conclusion

Bondable buttons are a better choice for achieving Maxillomandibular Fixation in comparison with Maxillomandibular Fixation screws for the treatment of minimally displaced mandibular fractures. Further studies with a bigger sample size must be carried out.

FAMI Screws for Mandibulo-Maxillary fixation in mandibular fracture treatment - Clinico-radiological evaluation

Mandibulo-maxillary fixation (MMF) is indispensable for mandibular fracture treatment. Various means for MMF have been proposed, of which arch bars are widely considered to be the mainstay. However, disadvantages to this method have initiated a quest for an alternative, leading to the introduction of MMF screws. MMF screws have frequently been criticized for poor stability of fracture sites, root damage, hardware failure, and nerve damage. We retrospectively evaluate the FAMI (Fixation and Adaptation in Mandibular Injuries) screw in mandibular fracture treatment by scanning for clinically and radiologically visible complications. In total, 534 FAMI screws were used in the successful treatment of 96 males and 34 females. Condylar fractures were most commonly encountered, representing 120 of 241 fracture sites. 15 general fracture-related complications occurred, with the most common being nerve function impairment (3.8%) and postoperative malocclusion (4.6%). In nine cases (7%), clinically visible FAMI-screw-related complications occurred, with the most prevalent being screw loosening (2.3%) and mucosal signs of inflammation (3.1%). Duration of FAMI screws was associated with the occurrence of clinically visible complications (p = 0.042). Radiologically, clinically invisible dental hard tissue damage was noted in 21 individuals (16%). Therefore, FAMI screws seem to be a reliable and safe method for mandibulo-maxillary fixation.

Dental occlusion ties: A rapid, safe, and non-invasive maxillo-mandibular fixation technology

Objectives

For decades, Erich arch bars have been a standard in establishing maxillo‐mandibular fixation (MMF). While reliable, the approach risks sharps injury, consumes operating room time, and inflicts gingival trauma. Newer technologies including screw‐based techniques and “hybrid” techniques have improved MMF by reducing sharps injuries and operating room time, but risk injury to tooth roots, nerves, and gingiva. This study aims to establish the application, strengths, and limitations of dental occlusion ties as a novel alternative in maxillo‐mandibular fixation.

Study Design

Prospective, non‐blinded, human feasibility clinical trial.

Materials and Methods

An iterative prototyping process was used to invent dental occlusion ties (brand name: Minne Ties). Development included 3D printing, cadaver prototype testing, human apical embrasure measurement, and ultimately non‐significant risk human clinical trial testing. In the IRB‐approved feasibility clinical trial, the devices were applied to mandible and maxilla fracture candidates with fractures amenable to intra‐operative MMF with open reduction with internal fixation. The ties were removed prior to extubation. Pre‐teens, comminuted fracture patients, and patients requiring post‐operative MMF were excluded.

Results

Manufactured, sterile prototypes secured MMF successfully in management of unilateral and bilateral mandible and maxilla fractures. All patients reported correction of pre‐operative malocclusion. Application times were typically 12–15 minutes for a single surgeon to achieve MMF. Patients incurred negligible gingival trauma from the technology as the ties require no tissue penetration for application.

Conclusions

Dental occlusion ties offer a non‐invasive solution featuring operating room efficiency, minimized sharps risk, and less bony and soft tissue trauma than current commercialized solutions.

Level of Evidence

Therapeutic, IV

Drill-related root injury caused by intraoperative intermaxillary fixation: an analysis of 1067 screw applications

BACKGROUND/AIMS

Intermaxillary fixation is a standard procedure for the treatment of mandibular fractures or in orthognathic surgery. Predrilling for screws poses the risk of accidental tooth root injury, potentially leading to further pathological processes. Limited evidence about accidental tooth injury during intermaxillary fixation is available due to heterogenous study designs. The aim of this study was to evaluate the risk of root trauma using predrilled transgingival fixation screws and the clinical consequences for the affected teeth.

MATERIALS AND METHODS

In this retrospective study, the data of open reduction and internal fixation surgery files with intraoperative application of predrilled intermaxillary fixation screws were analysed. The postoperative radiographic images were evaluated for the occurrence of tooth root injury. Patients diagnosed with root injury were clinically followed up with respect to the dental health for the affected teeth.

RESULTS

A total of 133 radiologically diagnosed tooth root injuries were recorded (12.5% of screws). The median follow-up interval was 16 months (range: 3-77 months). The return rate was 49.5% for all patients. Of these, four of the injured teeth (3%) needed endodontic treatment. No toothache was reported, no tooth was lost, and no negative impact on periodontal health was clinically evident.

CONCLUSION

Intermaxillary fixation with predrilled transgingival screws is a safe way to manage mandibular fractures. The incidence of tooth root injury is not uncommon, but the adverse side effects are rare and the health of the affected teeth is mostly not compromised.

Insertion torque recordings for the diagnosis of contact between orthodontic mini-implants and dental roots: a systematic review

BACKGROUND

Most orthodontic mini-implants (OMIs) are inserted between dental roots. The prevalence of contacting these structures is high. Such contacts can cause permanent root damage and implant instability. Increased torque levels during implant insertion (the index test) could be a more accurate and immediate measure for diagnosing implant-root contact (the target condition) than radiographs (the reference standard) and could ultimately lead to a reduction or elimination of X-ray exposure. To address this issue, we asked three questions: (1) whether OMIs with root contact had higher insertion torque values than those without, (2) what is the accuracy of the index test compared with the reference standard to diagnose the target condition and what are the adverse effects of the index test, and (3) whether intermediate torque values have clinical diagnostic utility.

METHODS

Methods were conducted according to our published protocol, which was based on the PRISMA-P 2015 statement. We applied broad spectrum eligibility criteria that included randomized and non-randomized studies on clinical, animal, and cadaver models. Not including such models would be unethical because it could slow down knowledge creation on the adverse effects of implant insertion. We conducted searches in more than 40 electronic databases including MEDLINE and 10 journals were hand-searched. Grey literature and reference lists were also searched. All research procedures were conducted independently by three reviewers. Authors of selected studies were contacted to obtain additional information. Outcomes on the three different research models were analysed separately. Systematic error was assessed with the Cochrane 'Risk of bias tool' for non-randomized studies.

RESULTS

One clinical, two animal, and two cadaver studies fulfilled the eligibility criteria of the first research question. All studies and subgroups demonstrated higher insertion torque values for OMIs with the target condition than those without. Mean differences (MD) between these effect estimates were statistically significant in one beagle model (MD, 4.64; 95 % CI, 3.50 to 5.79) and three subgroups of cadaver studies (MD, 2.70; 95 % CI, 1.42 to 3.98) (MD, 3.97; 95 % CI, 2.17 to 5.78) (MD, 0.93; 95 % CI, 0.67 to 1.20). Highest mean differences were identified in most self-drilling compared with pre-drilling groups. Clinical heterogeneity between studies was high, and many items were underreported. All studies except one cadaver study scored at least one domain as 'serious risk' of bias. No studies addressed the second research question. One cadaver study addressed the third question which showed the importance of recording torque levels during the entire implant insertion process. Responses of contacted authors were helpful, but often difficult to obtain. Implants fractured in one animal and in one cadaver model.

CONCLUSIONS

All eligible studies scored higher insertion torque values for implants with root contact than those without, but none of these studies assessed the diagnostic accuracy of the index test. The inclusion of non-randomized and animal and cadaver models in this systematic review provided key findings that otherwise would have been wasted. Such studies are important in the context of the wide applicability of this test, the high prevalence of the target condition, and the underreporting of adverse effects of interventions. A protocol for a potential new diagnostic pathway was presented, and the importance of contacting authors was addressed. The applicability of the findings should be interpreted in the context of underreporting and the many limitations of the included studies.

Severe tooth loss after root damage caused by predrilled intermaxillary fixation screw: a case report

Intermaxillary fixation (IMF) with screws is routinely used as a conservative therapy or to obtain normal occlusion during the surgical procedure of open reduction and internal fixation for treating mandibular fractures. The risk of iatrogenic dental damage caused by interdental drilling is widely known. Several side effects are described, including loss of response to pulp sensibility testing, root fracture, and, loss of the tooth. This is a case report about a young man who had undergone temporary IMF treatment with a single proven root damage. The patient did not appear for follow-up but he presented 5 years afterward with local purulent osteomyelitis concerning the affected and the adjacent teeth. Osteotomy and extraction of two premolars and one molar were necessary for rehabilitation. This case report illustrates the importance of careful use of predrilled IMF screws and the necessity of frequent follow-ups in cases of proven tooth root damage due to IMF treatment.

Insertion torque recordings for the diagnosis of contact between orthodontic mini-implants and dental roots: protocol for a systematic review

BACKGROUND

Hitting a dental root during the insertion of orthodontic mini-implants (OMIs) is a common adverse effect of this intervention. This condition can permanently damage these structures and can cause implant instability. Increased torque levels (index test) recorded during the insertion of OMIs may provide a more accurate and immediate diagnosis of implant-root contact (target condition) than radiographic imaging (reference standard). An accurate index test could reduce or eliminate X-ray exposure. These issues, the common use of OMIs, the high prevalence of the target condition, and because most OMIs are placed between roots warrant a systematic review. We will assess 1) the diagnostic accuracy and the adverse effects of the index test, 2) whether OMIs with root contact have higher insertion torque values than those without, and 3) whether intermediate torque values have clinical diagnostic utility.

METHODS

The Preferred Reporting Items for Systematic review and Meta-Analysis Protocols (PRISMA-P) 2015 statement was used as a the guideline for reporting this protocol. Inserting implants deliberately into dental roots of human participants would not be approved by ethical review boards and adverse effects of interventions are generally underreported. We will therefore apply broad spectrum eligibility criteria, which will include clinical, animal and cadaver models. Not including these models could slow down knowledge translation. Both randomized and non-randomized research studies will be included. Comparisons of interest and subgroups are pre-specified. We will conduct searches in MEDLINE and more than 40 other electronic databases. We will search the grey literature and reference lists and hand-search ten journals. All methodological procedures will be conducted by three reviewers. Study selection, data extraction and analyses, and protocols for contacting authors and resolving conflicts between reviewers are described. Designed specific risk of bias tools will be tailored to the research question. Different research models will be analysed separately. Parameters for exploring statistical heterogeneity and conducting meta-analyses are pre-specified. The quality of evidence for outcomes will be assessed through the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

DISCUSSION

The findings of this systematic review will be useful for patients, clinicians, researchers, guideline developers, policymakers, and surgical companies.

Translational mini-screw implant research

It is important to thoroughly test new materials as well as techniques when these innovations are to be utilized in the human clinical situation. Translational research fills this important niche. The purpose of translational research is to establish the continuity of evidence from the laboratory to the clinic and in so-doing, provide evidence that the material is functioning appropriately and that the process in the human will be successful. This concept applies to the mini-screw implant; which, has been very successfully introduced into the orthodontic armamentarium over the last decade for application as a temporary anchorage device. The examples of translational research that will be illustrated in this paper have paved the way to ensure that clinicians have evidence to confidently utilize mini-screw implants in orthodontic practice. Needless to say, more studies are needed to ensure a safe, effective and efficient manner to practice orthodontics.

The Use of MMF Screws: Surgical Technique, Indications, Contraindications, and Common Problems in Review of the Literature

Mandibulo-maxillary fixation (MMF) screws are inserted into the bony base of both jaws in the process of fracture realignment and immobilisation. The screw heads act as anchor points to fasten wire loops or rubber bands connecting the mandible to the maxilla. Traditional interdental chain-linked wiring or arch bar techniques provide the anchorage by attached cleats, hooks, or eyelets. In comparison to these tooth-borne appliances MMF screws facilitate and shorten the way to achieve intermaxillary fixation considerably. In addition, MMF screws help to reduce the hazards of glove perforation and wire stick injuries. On the downside, MMF screws are attributed with the risk of tooth root damage and a lack of versatility beyond the pure maintenance of occlusion such as stabilizing loose teeth or splinting fragments of the alveolar process. The surgical technique of MMF screws as well as the pros and cons of the clinical application are reviewed. The adequate screw placement to prevent serious tooth root injuries is still an issue to rethink and modify conceptual guidelines.

Management of paediatric mandibular condylar fractures with screw-based semi-rigid intermaxillary fixation

This study was designed to evaluate the feasibility and safety of screw-based semi-rigid intermaxillary fixation (IMF) combined with a specially designed occlusal splint in the conservative treatment of paediatric mandibular condylar fractures. Thirteen paediatric patients with 20 sides of condylar fractures treated with semi-rigid IMF were analyzed retrospectively. Semi-rigid IMF was achieved by inserting self-drilling IMF screws into the anterior alveolar bone of the maxilla and mandible suspended with elastic bands. An occlusal splint with a molar fulcrum was used for functional repositioning of the condylar fragment. After 4 weeks, the screws and occlusal splint were removed. During a mean period of 28.6 months' follow-up, the patients' maximal mouth opening increased to a mean of 37.69 mm. Clinical and radiological examinations revealed satisfactory results in facial symmetry and condylar remodelling. No clinical symptoms or radiographic evidence showed dental injuries associated with screw insertion. This study suggests that this method might be a safe, easy, and effective management of paediatric condylar fractures.

Retrospective Study on Efficacy of Intermaxillary Fixation Screws

BACKGROUND

We evaluated the efficacy of intermaxillary fixation (IMF) screws in the treatment of mandibular fractures.

METHODS

Two hundred patients with mandibular fractures, treated by IMF using these screws, were evaluated by pre and postoperative panoramic radiographs. Clinical testing was carried out for vitality and abnormal mobility of teeth adjacent to the site of screw insertions. Other factors such as possible iatrogenic dental injuries, loss, breakage or screw cover by oral mucosa and postoperative occlusion were also studied.

RESULT

The most important complication noticed was iatrogenic damage to dental roots.

CONCLUSION

Use of intraoral cortical bone screws for IMF is a valid alternative to arch bars in the treatment of mandibular fractures. Iatrogenic injury to dental roots is the commonest problem which can be minimized by an experienced surgeon.

Embrasure wires for intraoperative maxillomandibular fixation are rapid and effective

PURPOSE

The management of some mandible fractures requires maxillomandibular fixation (MMF) intraoperatively but not postoperatively. Intraoperative MMF with arch bars has significant disadvantages, including duration of application and risk of disease transmission. Some surgeons have sought to minimize these disadvantages, improve efficiency, and decrease cost by omitting formal MMF altogether and manually stabilizing the occlusion. Embrasure wires are a method of intraoperative MMF with significant potential advantages. The purpose of this investigation was to compare embrasure wires with Erich arch bars (Karl Leibinger Co, Mulheim, Germany) for intraoperative stabilization of mandible fractures.

PATIENTS AND METHODS

This retrospective case review comprised 50 patients with a primary diagnosis of mandible fracture requiring open reduction-internal fixation with intraoperative MMF. Patients were categorized into 2 groups: intraoperative MMF using embrasure wires (group A) or intraoperative MMF using arch bars (group B). In each group the time required to place the MMF was recorded in whole minutes. The success or failure of the technique to maintain stable MMF throughout the procedure was assessed.

RESULTS

Intraoperative MMF was used with embrasure wires in 27 of 50 patients (54%) and with arch bars in 23 of 50 (46%). The mean time required for placement of embrasure wire MMF (2.51 minutes) was significantly (P < .001) less than the mean time required for placement of arch bar MMF (25.47 minutes). The quality of MMF was judged to be stable for the duration of fixation in 24 of 27 patients (89%) in the embrasure wire MMF group and 22 of the 23 patients (96%) in the arch bar group. This difference was not significant (P = .61).

CONCLUSION

Embrasure wires can be placed in significantly less time than arch bars, and they provide a reliable form of intraoperative MMF during mandible fracture repair. For intraoperative MMF, embrasure wires offer significant advantages compared with arch bars by reducing application time. In addition, embrasure wires may reduce the risk of disease transmission by decreasing the number of wires required for MMF.

Predictable drill-free screw positioning with a graduated 3-dimensional radiographic-surgical guide: a preliminary report

INTRODUCTION

Mini-implants are placed in restricted sites, requiring an accurate surgical technique. However, no systematic study has quantified technique accuracy to reliably predict the surgical risks. Therefore, a graduated 3-dimensional radiographic-surgical guide (G-RSG) was proposed, and its inaccuracy and risk index (RI) were estimated.

METHODS

The sample consisted of 6 subjects (4 male, 2 female), who used mini-implant anchorage. Ten drill-free screws (DFS) were placed by using the G-RSG. The central point of the mesiodistal septum width (SW) was the selected implant site on the presurgical radiograph. The distances between DFS and the adjacent teeth (5-DFS and 6-DFS) were measured to evaluate screw centralization and inaccuracy degree (ID). These distances were statistically compared by independent t tests, and inaccuracy was determined by the expression ID = (5-DFS - 6-DFS)/2, which represents deviation of the mini-implant's final position regarding the central point initially selected. Then SW, ID, and screw diameter (SØ) were combined to estimate the surgical risk with RI expressed by RI = SØ/SW - ID.

RESULTS

The 5-DFS and 6-DFS distances were not significantly different. The ID of the G-RSG was 0.17 mm. The low ID ensured a safe RI (<1) in spite of the restricted SW.

CONCLUSIONS

The G-RSG accuracy allowed fine prediction of the final DFS position in the interradicular septum, with a low RI, which is a helpful tool to estimate surgical risks.

Effects of intentional damage of the roots and surrounding structures with miniscrew implants

INTRODUCTION

The purposes of the study were to evaluate the immediate damage to roots and periodontal structures after initial miniscrew implant (MSI) placement and the short- and long-term damage after MSIs were left in situ.

METHODS

The roots of the maxillary second, third, and fourth premolars of 7 mature beagle dogs were randomly assigned to undergo immediate, short-term (left for 6 weeks), or long-term (left for 12 weeks) damage. Intentional damage was inflicted with self-tapping screws (1.8 x 8 mm) placed with a stent. Alternating tetracycline and calcein labels were administered at 6-week intervals. Undecalcified sections were stained and evaluated histologically to determine the extent of damage; healing was evaluated by using fluorescence labels.

RESULTS

Histology showed damage to 73.8% of the teeth, ranging from displacement of bone into the periodontal ligament to invasion of the pulp chamber. Displacement of bone into the periodontal ligament and direct damage to the periodontal ligament occurred in 3 (7.2%) instances. Damage was isolated to the cementum of 8 (19.0%) teeth, whereas damage occurred in the dentin of 11 (26.2%) teeth. Loss of bone in the furcation was evident in 3 (7.2%) teeth, and severe damage into the pulp occurred in 6 (14.2%) teeth. No differences in the amounts of damage were evident between the immediate, short-, and long-term groups. Healing often occurred with cementum around the unloaded MSIs.

CONCLUSIONS

Extensive damage can be caused by MSIs, with little to no differences evident over time. Unloaded MSIs that remain in contact with roots of teeth can show varying degrees of healing.

Self-tapping and self-drilling screws for intermaxillary fixation in management of mandibular fractures

The current study evaluated the success and the possible complication of intermaxillary fixation with self-tapping and self-drilling screws (STSDSs) in nondislocated or slightly dislocated mandibular fractures.Forty patients with mandibular fractures, treated with intermaxillary fixation using STSDSs, were clinically assessed by means of a dental vitality test and evaluation of tooth mobility adjacent to the cortical screw holes, and radiologically by means of a panoramic dental radiograph upon removal of the screws.The main complication was screw loss in 4.4% of cases, followed by coverage by oral mucosa in 1.2% of cases. However, no dental root damage, screw breakage, malocclusion, or poor consolidation of mandibular fractures was observed.The use of STSDSs for intermaxillary fixation is a useful alternative to the use of arch bars in the treatment of some types of mandibular fractures. In addition, there is no risk of dental lesions as with self-tapping screws.

An audit of mandibular fractures treated by intermaxillary fixation using intraoral cortical bone screws

INTRODUCTION

During the last 10 years, intermaxillary fixation using intraoral cortical bone screws has been introduced for the treatment of mandibular fractures. The aim of this work was to evaluate the indications and possible complications of this method.

MATERIALS AND METHODS

Sixty-two patients with mandibular fractures, treated by intermaxillary fixation using these screws, were evaluated by preoperative and postoperative panoramic radiographs. Clinical testing was carried out for vitality and abnormal mobility of teeth adjacent to the site of screw insertions. To evaluate the efficacy of this method, different factors were considered such as possible iatrogenic dental injuries, loss, breakage or screw cover by oral mucosa and postoperative occlusion.

RESULTS

The most important complication was iatrogenic damage to dental roots (1.5%), 4.9% of the screws were covered by oral mucosa and 1.9% were lost, while none were broken. Malocclusion was observed in one patient (1.6%) and lack of consolidation of a displaced fracture of the mandibular body in another patient.

CONCLUSIONS

Use of intraoral cortical bone screws for intermaxillary fixation is a valid alternative to arch bars in the treatment of mandibular fractures. Iatrogenic injury to dental roots is the most important problem of this procedure, but can be minimized by an experienced surgeon.

A drill-free bone screw for intermaxillary fixation in military casualties

Drill-free bone screws are a simple and quick method of establishing intermaxillary fixation requiring a minimum amount of specialist training or equipment. These screws offer significant advantages over other methods of intermaxillary fixation and are well suited for use in military casualties.