This systematic review examined the literature for evidence of dental root damage after contact with intermaxillary screws (IMS). Electronic databases, including the Cochrane Library, Ovid, Scirus, Scopus and Virtual Health Library, were used to search for original articles from 1980 to January 2011. Prospective and retrospective studies that assessed the association of root damage and contact with IMS were selected. Two authors independently reviewed and extracted the data from the included studies. A methodological quality scoring process was used to classify whether the articles presented low, moderate or high evidence. The search retrieved 795 citations. Nine studies fulfilled the initial selection criteria. Of these studies, 3 were excluded. Two studies did not note any iatrogenic injuries of the dental roots; the other study was a case report. Of the 6 included articles, 2 were ranked as having low and four as having moderate evidence. The moderate evidence found suggested that the roots did not exhibit clinical changes after coming into contact with the IMS, but this situation depends on the root damage level. To obtain reliable scientific evidence, studies with an adequate sample size and diagnostic methods are required to confirm the effects of IMS on the dental root.
Several methods have been used for temporary intermaxillary fixation (IMF) during the treatment of some maxillofacial fractures. The use and application of arch bars or eyelet wires are often described, but this technique is difficult to apply to carious, periodontally compromised and crowded teeth. The wires that are tightened around the teeth during the arch bar application may cause ischaemic necrosis of the mucosa, extrusion and subsequent loss of vitality of the teeth. These wires also make it difficult to maintain gingival health. Although these techniques are widely used, there are several drawbacks that have led to the development of other means for maxillofacial fixation, particularly screws, that are independent of dental fixation.
Intermaxillary screws (IMS) are associated with several advantages over the wire and arch bars. IMS can be placed and removed easily. They are well tolerated by patients, allow oral hygiene to be maintained easily and minimize the risk of a needle stick injury to the operator. The main concern with IMS is the potential of damaging the teeth due to contact.
Despite the excellent results of clinical reports, the routine use of IMS can lead to complications, such as screw fracture, peri-implant mucositis, mucosal lesions, injury to the incisal papilla when the screws and rubber band are used in the incisal area and root injury. Among these complications, root injury is the most harmful to the patient. Root contact can occur if the IMS are placed between the roots. Recommendations regarding the placement of the screws have been published, but careful attention must be paid to the three-dimensional relationship of the path of insertion with the surrounding dental structures to reduce iatrogenic dental trauma. After dental trauma, root resorption is considered the most detrimental result and the most frequent cause of tooth loss. It is important for the clinician to understand the potential risks associated with this procedure and how to address this complication when it happens.
The purpose of this study was to systematically review the literature for evidence of dental root damage after contact with IMS.
Material and methods
In an attempt to identify relevant studies (from 1980 to the third week of January 2011), irrespective of language, a detailed search was conducted in the following electronic databases: Cochrane Library, Ovid, Scirus, Scopus and VHL (Virtual Health Library).
The search strategy included appropriate changes in the keywords and followed the syntax rules of each database. The main keywords used were surgical screw, intermaxillary screw, osteosynthesis screw, transalveolar screw and damaged root. A detailed search strategy was developed for each database and used to identify studies (published and unpublished) to be considered in this systematic review ( Table 1 ).
|Databases||Websites||Date||Keywords and DeCS/MeSH||Refining|
|Cochrane Library||cochrane.bvsalud.org||Until January 2011||Screw and root||–|
|Ovid||1980 to January 2011||Screw or intermaxillary screws or osteosynthesis screws or transalveolar screws and root||Select resources – Ovid MEDLINE
Limit – Human
|Scirus||www.scirus.com||1980 to January 2011||Screw or intermaxillary screws or osteosynthesis screws or transalveolar screws and root||Information type – abstracts, articles
Journal sources – MEDLINE/PubMed; ScienceDirect
Subject area – Life Science; Medicine
Limit – Human
|Scopus||www.scopus.com||1980 to January 2011||Screw or intermaxillary screws or osteosynthesis screws or transalveolar screws and root||Subjects areas – Life Sciences, Health Sciences
Document type – article
Source title – American Journal of Orthodontics and Dentofacial Orthopedics
|VHL||regional.bvsalud.org||Until January 2011||Orthodontic Anchorage Procedures and Tooth Root||–|
The following journals were searched manually to complement the search: the British Journal of Oral and Maxillofacial Surgery, Clinical Oral Implants Research, International Journal of Oral & Maxillofacial Surgery, Journal of Cranio-Maxillofacial Surgery, Journal of Oral and Maxillofacial Surgery and Journal of Orofacial Orthopedics and Orthognathic Surgery. The reference lists of the retrieved articles were also manually searched for additional relevant publications that could have been missed in the database searches.
The inclusion criteria were: prospective clinical studies and retrospective clinical studies; human clinical studies; surgical screws with a diameter less than 2.5 mm because larger screws would not be used in the interradicular regions; root contact evaluation associated with the use of surgical screws; and no age or gender restrictions. The technique articles, case reports, opinion articles, reviews, animal and in vitro studies were excluded.
The titles and abstracts of all potentially relevant articles were reviewed. The full text of all relevant articles and articles with ambiguous titles and abstracts were collected and reviewed. Any specific data that were not described in the article were obtained by contacting the authors. Two readers (M.A.J. and C.B.) independently reviewed each article, and the information collected by these two readers was compared. Conflicts were resolved by discussing each article to reach a consensus.
The articles that fulfilled all of the inclusion criteria underwent a methodological quality assessment, a modified version described by Feldmann and Bondemark, to document the methodological soundness of each article. The following five variables were evaluated: sample size, study design, selection description, diagnostic methods and follow-up. The study could score a maximum of 10 points and was categorized as having low (0–5 points), moderate (6–8 points), or high (9 or 10 points) evidence ( Table 2 ).
|1. Sample size||Number of affected teeth||0–10 = 0 point;
11–20 = 1 point
≥21 = 2 points
|2. Study design||Prospective study (PS), retrospective study (RS)||PS = 3 point
RS = 1 point
|3. Selection description||Description of the evaluated teeth, and the characterization of intermaxillary screws (diameter and length)||Teeth or intermaxillary screws description = 1 point
Teeth and intermaxillary screws description = 2 point
|4. Diagnostic methods||Diagnostic methods used to evaluate the tooth after trauma||Radiographic = 1 point
Radiographic and vitality test = 2 point
|5. Follow-up period post-damage||Evaluation time post-trauma||<6 months – 0 point
≥6 months – 1 point
Each electronic database search yielded different numbers of records. Most of the abstracts were identified with Scirus (365), followed by Ovid (327), VHS (53), Cochrane Library (26) and Scopus (24). 795 titles and abstracts regarding surgical screws and root damage were identified in these databases ( Fig. 1 ).
Of these 795 titles, 382 were duplicated; therefore, these were counted only once. All unique titles and abstracts (413) were analysed according to the exclusion criteria, and 404 were excluded. The full texts of the remaining 9 studies were assessed. Among these studies, 3 were excluded. Two studies did not note any iatrogenic injuries of the dental roots; the other study was a case report. Only 6 articles were qualified for the final analysis. Table 3 shows the quality assessment of the included studies.
|Authors||Sample size||Study design||Selection description||Diagnostic methods||Follow-up||Total score||Judged methodological quality standard|
|Borah and Ashmed||1||1||1||2||1||6||Moderate|
|Coletti et al.||0||1||2||1||0||4||Low|
|Fabbroni et al.||2||3||1||2||0||8||Moderate|
|Roccia et al.||0||1||2||2||1||6||Moderate|
|Sahoo et al.||0||1||2||2||1||6||Moderate|
|Schortinghuis et al.||0||1||2||1||1||5||Low|
No new articles were found in the manual search. The summary details of the final selected studies are recorded in Table 4 . Overall, the analysed data comprised 597 patients treated with 3647 IMS. There was root damage in 88 teeth, which occurred accidentally in the patients submitted to surgical treatment. Only 18 teeth were nonvital, and three teeth were extracted. A moderate percentage of the affected teeth were probably transfixed by IMS that contacted the dental lamina–dentine without injuring the pulp space or the apical neurovascular bundle.
|Study||Borah and Ashmed ; 5-year retrospective study|
|Methods||Radiographic diagnostic and dental vitalometer methods|
|Participants||387 patients (235 males and 152 females); mean age of 29 years|
|Interventions||Patients submitted to surgical treatment for facial injury; 2300 self-tapping screw, ranged from 5 to 8 mm in length and width 1.5 or 2.5 mm|
|Outcomes||13 roots in 13 patients were transfixed. Ten transfixed teeth tested as nonvital (seven in the mandible and three in the maxilla). The follow-up period ranged from 6 to 60 months|
|Study||Coletti et al. ; retrospective study|
|Interventions||Patients requiring intermaxillary fixation; 229 self-drilling/tapping screws with 2.0 mm in diameter and 8.0 or 12 mm in length|
|Outcomes||First premolar root fractures occurred in 2 patients. The follow-up period ranged from 6 to 8 weeks. Both teeth were subsequently extracted.|
|Study||Fabbroni et al. ; prospective study|
|Methods||Radiographic diagnostic and eletronic pulp tester methods|
|Participants||55 patients (54 male and 1 female); age range 16–52 years|
|Interventions||Patients submitted a surgical treatment for mandible fracture, 232 self-tapping transalveolar screws, titanium capstan headed screws with 10 or 15 mm in length and 2.0 mm in diameter|
|Outcomes||26 teeth had major contacts and 37 teeth had minor contacts. Six tested as nonvital (four in the mandible and two in the maxilla)|
|Study||Roccia et al. ; retrospective study|
|Methods||Panoramic radiographic and thermic pulp testing diagnostic method|
|Participants||62 patients; mean age, 33.3; range, 16–71 years|
|Interventions||Patients submitted a surgical treatment for mandible fracture, 265 self-tapping screws, 2.0 mm in diameter and 8.0 mm in length|
|Outcomes||Nine teeth damaged (seven premolars and two canines). All patients had a clinical follow-up of at least 6 months. Seven teeth remained vital and without abnormal mobility and two teeth were treated endodontically|
|Study||Sahoo et al. ; retrospective study|
|Methods||Panoramic radiographs and thermic pulp test|
|Participants||200 patients (137 males and 63 females); age range 15–65 years|
|Interventions||Patients submitted a surgical treatment for mandible fracture, 880 self-tapping titanium screws, 2 mm in diameter and 6–12 mm in length|
|Outcomes||Nine teeth damaged (five premolars and four canines). The damage consisted of indentation to the roots of seven teeth (no consequences for vitality or stability) and root canal perforation in two teeth (treated endodontically). All patients had a clinical follow-up of at least 6 months|
|Study||Schortinghuis et al. ; retrospective study|
|Methods||Radiographic diagnostic method|
|Participants||44 patients; mean age, 41.9 ± 14.7 years; range, 12–76 years|
|Interventions||Patients submitted to surgical treatment for severe maxillofacial trauma, 546 self-tapping mini-screws 1.0 mm in diameter and 3.0 or 4.0 mm in length; 75 mini-screws 1.5 mm in diameter and 3.5 or 4.0 mm long|
|Outcomes||One second premolar was perforated. The follow-up period ranged from 31 to 54 months. The premolar was removed after trauma because of a dentine fracture.|