Coronectomy Technique Research Articles

Coronectomy of impacted mandibular third molars: a clinical and radiological retrospective case series study with 2-9 years of follow-up.

Impacted mandibular third molars occasionally are in intimate relation to the inferior alveolar nerve (IAN). Coronectomy has been proposed as a good alternative to prevent injury of the IAN. The present study evaluates the clinical and radiological outcomes of impacted mandibular third molars presenting radiographic signs associated with a high risk of IAN injury, and which were treated with the coronectomy technique. A retrospective case series evaluated the outcomes of coronectomies of impacted mandibular third molars. The inclusion criteria were: available preoperative, immediate postoperative and two-year panoramic radiographs, preoperative cone-beam computed tomography (CBCT), and a complete case history. The clinical evaluation comprised intraoperative complications (mobilized fragments of root and damage to adjacent structures), short-term complications (sensory alterations and postoperative infection), and long-term complications (infection or oral exposure). The IAN position with respect to the roots, root shape, eruption status, third molar position, radicular-complex migration and bone above roots were radiographically evaluated as well. Approximately a total of 2000 mandibular third molars were removed from 2011 to 2022. Of these, 39 molars in 34 patients were partially extracted using the coronectomy technique. The mean age was 36 years (range 22-77), and the mean follow-up was 28 months (range 24-84). There were two short-term postoperative infections. One of them was resolved through reintervention to remove the roots after antibiotic treatment, while the other required hospital admission and removal of the roots. One case of short-term transient lingual paresthesia was also recorded. Two long-term oral exposures were detected, and the root fragments had to be extracted. There were no permanent sensory alterations. In our case series of 39 impacted mandibular molars in intimate contact with the IAN and treated with the coronectomy technique, the number of complications was low (two infections and a single case of transient lingual paresthesia), and no permanent sensory alterations were observed. Prospective studies, especially randomized clinical trials, are needed to compare this technique with conventional extraction.

Coronectomy of the wisdom teeth: the dental extraction alternative

Background. Coronectomy of the wisdom teeth is an alternative surgical procedure to tooth extraction, which aims to preserve the roots of the wisdom teeth in the dental socket after surgical separation of the crown, in order to avoid the injury of the inferior alveolar vascular-nervous bundle. Purpose. Minimizing the damage to the inferior alveolar nerve when extracting lower third molars caused by the intimate relationship between the nerve and the roots of the teeth, by using the technique of coronectomy, or intentional root retention. Material and Methods. Patients who reported to University Dental clinic during the period 2020–2021 for surgical removal of impacted L3M were screened for nerve–root relationship with OPG or CBCT. 15 patients underwent coronectomy as a procedure to remove the crown and upper third of the roots of a lower third molar to reduce the risk of damage to the inferior alveolar nerve. Results. 15 patients were enrolled in this study, with a total of 17 lower third molars. Sixteen sites healed primarily, but in 1 case the sockets on both sides opened and failed to close secondarily. In this case, the root fragments were later removed and found to be mobile. Conclusion. Coronectomies are safer to perform than complete extractions in situations in which the third molar is in close proximity to the mandibular canal. The technique appears to be associated with a low incidence of complications and the removal of remaining roots is required in around 6-7% of cases due to the mesial migration of the fragment and not any symptoms or reinfection.

Does the Coronectomy a Feasible and Safe Procedure to Avoid the Inferior Alveolar Nerve Injury during Third Molars Extractions? A Systematic Review.

This systematic review aimed to review the literature on the coronectomy technique and evaluate the incidence of success and complications as a surgical approach for inferior third molars. Online databases were searched for data on the frequency of inferior alveolar nerve damage, lingual nerve damage, root migration, pain, infection, dry socket, and extraction of the remaining root, and data on the necessity of reintervention were also extracted. Randomized clinical trials, controlled clinical trials, prospective cohort studies, and prospective and retrospective studies with or without the control group were intercepted. This systematic review was registered in PROSPERO (CDR 42020135485). Sixteen papers analyzed 2176 coronectomies in total, and only five of them were judged as appropriate according to methodological quality assessment. The incidence of inferior alveolar nerve injury was documented in 0.59% of the procedures, lingual nerve injury in 0.22%, infection 3.95%, dry socket 1.12%, extraction of the root 5.28%, and reintervention 1.13%. The pain was the most reported, in 22.04% of the population. This study provides an overview of the clinical success and complications of coronectomy, and their prevalence. A coronectomy may be considered a low-risk procedure and an option for treatment to avoid potential damage to nervous structures. However, patients should still undergo a full screening and evaluation of postsurgical procedures.

Neurosensory Deficits of Inferior Alveolar Nerve Following Impacted Mandibular Third Molar Extraction: Comparison of One-Stage Complete Extraction with Two-Stage Partial Coronectomy Surgical Technique.

Inferior alveolar nerve neurosensory deficit is a worrisome complication of surgical extraction of impacted mandibular third molars. A novel approach using two-stage partial coronectomy has been proposed as an alternative surgical procedure to reduce this complication. This study compared neurosensory deficits of inferior alveolar nerve following impacted mandibular third molar extraction using one-stage complete extraction with the two-stage partial coronectomy technique. Subjects with mesioangular or horizontal impacted mandibular third molar with an intimate relationship with inferior dental canal who met the inclusion criteria were recruited for the study. Subjects were divided into one-stage and two-stage partial coronectomy techniques. The subjects were evaluated for the presence of inferior alveolar neurosensory deficit, and the relationships of neurosensory nerve deficit with sex, age and type of impaction. Neurosensory deficit was observed in 5 subjects (7.8%), with all cases seen in the one-stage group. This difference was statistically significant (p = 0.03). The relationship between the incidence of neurosensory deficit and age, sex, type of impaction, surgical difficulty, operating time and root morphology was not statistically significant (p > 0.05). Findings from this study suggest partial coronectomy compared to one-stage complete extraction reduces the incidence of Inferior alveolar nerve neurosensory deficit.

Coronectomy of mandibular third molars: a systematic literature review and case studies.

Extraction of mandibular third molars (M3M) close to the inferior alveolar nerve (IAN) has a higher risk of neurological disturbance. This review aims to evaluate the evidence supporting the use of the coronectomy technique compared to complete extraction for such M3Ms. Case studies by a specialist oral and maxillofacial surgeon are included to illustrate clinical practice. Three databases (Cochrane Library, Embase, PubMed) were searched (November 2020). Additional articles were sought by hand searching the reference list of included articles. All studies published in English comparing outcomes of coronectomy with complete extraction with at least 50 subjects and 6months follow-up were included. Of the six included studies, five reported a lower rate of IAN disturbance after coronectomy compared with complete extraction. There were no reported cases of lingual nerve disturbance. Other outcomes of coronectomy such as pain, infection, alveolar osteitis were either similar or lower compared to complete extraction. There were high rates of root migration but low rates of exposure and reoperation. Follow-up protocols varied considerably. There is medium quality evidence to support the option of coronectomy for high risk M3M cases. Further studies to develop follow-up protocols to assist general dental practice is warranted.

The Use of Coronectomy to Manage Symptomatic Mandibular Third Molars: Techniques, Pitfalls and Suggested Guidelines

Coronectomy is a valuable technique in the management of symptomatic mandibular third molars at high risk of inferior alveolar nerve injury. When applied appropriately, the technique may reduce the incidence of inferior alveolar nerve injury in comparison to full surgical removal. Currently, no definitive guidelines exist on when to opt for coronectomy versus full surgical removal, and therefore significant variation in clinical practice exists. This article summarizes the surgical stages involved in the coronectomy procedure, reviews the indications and hazards of the technique, and finally provides suggested guidelines to assist the practitioner in the decision-making process of when to opt for coronectomy versus full surgical removal in the management of symptomatic mandibular third molars. CPD/Clinical Relevance: To review the coronectomy technique and highlight potential hazards with inappropriate application of the technique.

Modified coronectomy procedure for mandibular third molar: association of platelet-rich fibrin

ABSTRACT The present case report describes a modified technique of coronectomy for mandibular third molar with association of Platelet-Rich Fibrin Graft (PRF). The panoramic radiograph showed proximity of the roots of the vertical positioned 48 tooth with the superior wall of the mandibular canal, since the erasure of the superior cortical of the mandibular canal was observed. Due to the risk of injury to the inferior alveolar nerve, the technique of coronectomy was chosen. After the realized the coronectomy, in order to promote the regeneration of soft and hard tissues and also to prevent pulp changes that could lead to pain, pulp necrosis and infection, the PRF graft was used to fill the surgical defect formed by removal of the crown. Good healing evolution was observed and after 12 months of clinical and radiographic follow-up there was complete bone formation in the area where the crown was removed and no complications were observed.

Tratamento de terceiros molares inclusos através da técnica coronectomia – aspectos clínicos

Nerve damage during third molars removal is an inherent risk of the procedure due to the anatomical proximity of these structures. Coronectomy is an effective technique that can reduce the risk of developing paresthesia caused by this injury. The present study aims to report a clinical case in which the coronectomy was performed describing its technique. The procedure was performed on a 25-year-old male patient, with third molars removal indication. The radiological exam suggested an intimate relationship between the lower right third molar roots and the mandibular canal. The coronectomy technique was performed under local anesthesia and the follow-up was performed after seven days, four months and four years. One week after surgery patient reported good recovery and does not showed radiographic signs or clinical symptoms of sensory or other pathological disorders. After four years, a new radiography was performed, where sign of peripheral bone formation and the absence of any pathological aspect or migration were observed. Considering the low complexity and morbidity of the technique, it becomes a good alternative to extraction, aiming to reduce the development of paresthesia in high-risk cases.

Assessment Of Impacted Lower Third Molar Coronectomy Through Vestibular Bone window .

Abstract Objective: The aim of the present study is to assess impacted lower third molar coronectomy through vestibular bone window. Subject and Methods: Twenty patients were allocated into two groups. In group 1, the standard coronectomy technique was performed while in group 2, coronectomy through vestibular bone window was done. Preoperative evaluation included examination of the site of surgery for the presence of inflammation, ulceration, discoloration or infection and measurement of the crevicular depth, maximal mouth opening and cheek dimension. OPG and CBCT were used to give full details on tooth and its relation to IAN. Results: Out of 20 patients only one (5%) had IANI. The mean crevicular depth was significantly less in vestibular window group than regular coronectomy. The mean MMO was larger in vestibular window group than regular coronectomy, the difference was nonsignificant. The mean cheek dimension was less in vestibular window group than regular coronectomy, the difference was nonsignificant. The mean VAS value was higher in group 2 than group 1; however, the difference between the two groups was nonsignificant. Conclusion: Coronectomy is a safe technique that greatly reduces the risk of IANI. Coronectomy through vestibular bone window technique may reduce periodontal pocket formation distal to the lower second molar. Vestibular bone window technique has no effect on postoperative sequelae (trismus, swelling and pain).

Coronectomy of partially erupted lower third molars performed by an undergraduate dentistry student: a case series.

The coronectomy technique is an alternative to conventional impacted tooth removal which aims to reduce the risk of damage to the inferior alveolar nerve (IAN). The technique is usually performed by senior oral surgeons or residents in training. Herein, patients were treated in a single service, in which coronectomy was performed by an undergraduate dental student on partially erupted lower third molars. A prospective analysis was performed on 21 individuals submitted to a total of 35 coronectomies. Clinical and radiographic follow-up was performed for at least 12 months. Overall, healing was within normal limits, without major complications and without permanent IAN injury. However, one case showed temporary IAN paraesthesia resolved within a month and two required repetitions of coronectomy due to the remaining enamel, but with a good final result. Root migration was observed in all cases, but no other surgery was required. Coronectomy may be an important option for treating partially erupted teeth in close nerve relationships, which could also be performed by trained undergraduate dental students. This series is interesting because it can encourage oral and maxillofacial surgeons to train undergraduate students and to stimulate their attraction and passion for surgery.

Outcomes after mandibular third molar coronectomy

ABSTRACT Coronectomy is an alternative technique to mandibular third molar removal to avoid inferior alveolar nerve impairment. It is indicated in cases where the dental roots are in close relationship with the nerve which results in a higher risk of damage and paresthesia. The coronectomy technique is considered a safe method to prevent inferior alveolar nerve injury, however it shows particular postoperative outcomes as migration and exposure of the retained roots, and possibility of additional intervention. The aim of this case series is to describe four different outcomes from coronectomy, in patients treated by the same protocol. The outcomes ranged from asymptomatic to migration, infection and root removal. Although the variety of outcomes, none of the patients showed inferior alveolar nerve impairment. Therefore, the main objective of coronectomy was reached.

Coronectomy in Third Mandibular Molars as an Alternative Treatment to Prevent Damage to the Inferior Alveolar Nerve: Bibliographic Review and 30 Cases Report

The inferior alveolar nerve (IAN) injury to remove the third molars is often caused by the intimate relationship between the nerve and the roots of the teeth. Coronectomy technique or intentional root retention, may minimize this problem. Thirty patients underwent coronectomy in 30 third molars with follow up of at least 6 months. Coronectomy technique deliberately protected the lingual nerve as part of the surgical procedure. All roots were at least 3 mm below the buccal and lingual bony walls. All patients were radiographed preoperatively, immediately postoperatively, and after 6 months. There were no cases of IAN damage involved in this study of 30 patients who underwent 30 coronectomies. There was one case of transient lingual nerve involvement, probably by the use of lingual retractor. One patient required subsequent removal of the roots of both lower third molars, due to lack of healing, and one patient required subsequent removal of a root cause of migration back to the surface. migration of the roots was observed in approximately 30 % of patients during a period of six months. Coronectomy seems to be a viable technique in those cases where the removal of all tooth could put the IAN at considerable risk of damage. The technique appears to be associated with a low incidence of complications, but the subsequent migration of the roots can be a problem in the long term.

The technical difficulties in oral surgery are leading many surgeons to believe that the coronectomy technique is always the best choice for the treatment of impacted third molars in intimate relation with the mandibular nerve. The objective of this study

The technical difficulties in oral surgery are leading many surgeons to believe that the coronectomy technique is always the best choice for the treatment of impacted third molars in intimate relation with the mandibular nerve. The objective of this study is to discuss conventional extraction and coronectomy, considering its respective advantages and the experience of the surgical team that can shed light on experts allowing to a better reflection on this trend and thus contributes to the best surgical choice. This clinical case reports a patient who presented the inferior third molar with impaction and root apices near of the mandibular nerve. Despite evidence to perform coronectomy, conventional extraction was done. The patient had no complications, displaying mild paresthesia during seven postoperative days. The immediate or late unpredictability of the coronectomy leads us to conclude that conventional extraction should be the technique of choice for the extraction of the third molar in close relation with the mandibular nerve, except in particular cases.

Update on coronectomy

Prevention of inferior alveolar nerve injury (IANI) related to surgery for high risk mandibular third molars (M3Ms) is possible. However, the justification for undertaking M3M coronectomy rather than removal is based upon risk assessment of the M3M, for which we have no clear parameters. This narrative review paper was undertaken by the author, aimed at highlighting the complexities around investigating, prescribing, patient consent and undertaking coronectomies. In order to assist the clinician in making surgical decisions faced with ever changing evidence base and lack of specific criteria for the coronectomy procedure. There is international acceptance of the coronectomy technique, however, there are many outstanding issues relating to the criteria for prescription, investigation and decision making for this procedure. A consensus is required to ensure that the terminology, assessment, operative and post-operative parameters are reported consistently for coronectomy, in order to develop appropriate and much needed evidence base for optimal patient care.

Third mandibular molar coronectomy: a way to prevent iatrogenic inferior alveolar nerve injuries—an systematic review

Introduction: In the field of oral and maxillo-facial surgery, the avulsion of third mandibular molar is a very common procedure. However, and although the injury on the alveolar inferior nerve is very rare, the neurological risk must not be underestimated. Indeed, it may lower the patient’s quality of life in a significant way. The coronectomy is a technique that allows us to avoid this risk. It consists in remaining in place the third mandibular molar’s roots. Educational objectives: After a clinical introduction to this surgical technique, the main characteristics of this type of procedure will be presented with the help of an exhaustive literature review. Thus, we will refer to the following subjects: the obvious decrease of neurological risks, the potential pre and post-operating complications, the potential necessity of an endodontic treatment for the residual roots, the becoming of these same roots, and finally the bony and mucosal cicatrization of the operated area. Conclusion: Every oral surgeon should have in mind this technique of coronectomy and master it. Indeed, when the case justifies it, the benefits are numerous for the patient.

The coronectomy technique for lower third molars: past and present

AbstractAimTo discuss the past and present evidence for the coronectomy technique for third molars.Materials and MethodsA review of the past and present literature related to the healing of extraction sockets in the presence of root fragments.ResultsHigh‐quality research studies surrounding the coronectomy procedure are lacking and it is important therefore that surgeons are aware that change of practice is not yet supported. The long‐term consequences, in terms of infection or other, are not known as study follow‐up is short.ConclusionIf coronectomy is to be considered then the authors would suggest that this is only for patients at high risk of potential nerve injury and that the patient is made aware of the risk of failure, the possible need for re‐operation and our lack of knowledge of long‐term consequences.

Coronectomy as a surgical approach to impacted mandibular third molars: a systematic review.

The aim of this systematic review was to evaluate the clinical effectiveness of the surgical technique of coronectomy for third molars extraction in close proximity with the inferior alveolar nerve.A literature survey carried out through PubMed, SCOPUS and the Cochrane Library from inceptions to the last access in January 31, 2014, was performed to intercept randomised clinical trials, controlled clinical trials, prospective cohort studies or retrospective studies (with or without control group) that examined the clinical outcomes after coronectomy. The following variable were evaluated: inferior alveolar nerve injury, lingual nerve injury, postoperative adverse effects, pulp disease, root migration and rate of reoperation. Ten articles qualified for the final analysis. The successful coronectomies varied from a minimum of 61.7% to a maximum of 100%. Coronectomy was associated with a low incidence of complications in terms of inferior alveolar nerve injury (0%-9.5%), lingual nerve injury (0%-2%), postoperative pain (1.1%-41.9%) and swelling (4.6%), dry socket infection (2%-12%), infection rate (1%-9.5%) and pulp disease (0.9%). Migration of the retained roots seems to be a frequent occurrence (2%-85.3%).Coronectomy appears to be a safe procedure at least in the short term, with a reduced incidence of postoperative complications. Therefore, a coronectomy can be indicated for teeth that are very close to the inferior alveolar nerve. If a second operation is needed for the remnant roots, they can be removed with a low risk of paresthesia, because the roots are generally receded from the mandubular nerve.

Notes on coronectomy

Coronectomy involves removal of a crown from roots of a healthy tooth in healthy patients indicated to prevent inferior alveolar nerve injury in a high risk case. Since the original paper in 2005 (2005; 43: 7-12) describing a prospective randomised study on coronectomy, there has been a lot of interest in this procedure and it has become routine practice in many oral surgery departments within the UK and USA. A significant variance in thresholds for prescribing coronectomy and also for the technique of its delivery has been highlighted by a recent review. This has resulted in frequent queries about the technique and which patients may be suitable. Thus this paper aims to highlight some finer points of the coronectomy technique and how to avoid potential pitfalls.

Coronectomy of third molar: a reduced risk technique for inferior alveolar nerve damage

Causing damage to the inferior alveolar nerve (IAN) when extracting lower third molars is due to the intimate relationship between the nerve and the roots of the teeth. When the proximity radiologic markers between the IAN and the root of the third molars are present, the technique of coronectomy can be proposed as an alternative to extraction to minimize the risk of nerve injury, with minimal complications. Nerve injury after the extraction of the mandibular third molar is a serious complication. The technique of coronectomy can be proposed to minimize the risk.

In reply

We would like to thank Dr Zola for the comments and interest. We agree that long-term follow-up is essential after a coronectomy procedure. In a study by Pogrel et al, 1 Pogrel M.A. Lee S.J. Muff D.F. Coronectomy: A technique to protect the inferior alveolar nerve. J Oral Maxillofac Surg. 2004; 62: 1447 Abstract Full Text Full Text PDF PubMed Scopus (148) Google Scholar 41 patients underwent coronectomy on 50 lower third molars with a mean follow-up of 22 months. Furthermore, in the same study, it has been suggested that a longer follow-up period may show more residual roots, requiring removal. However, in the current study, our goal was to determine the efficacy of the endodontic treatment with the coronectomy procedure and to discuss the necessity for endodontic treatment during coronectomies. Additionally, at the end of the first, third, and sixth months of the postoperative follow-up period, control radiographic examinations were performed and, finally, 1 year after the operation, the last panoramic radiographs were taken for assessment of the coronectomy sites. We think that 1-year follow-up is sufficient for determining the endodontic treatment-related symptoms. Coronectomy: A technique to protect the inferior alveolar nerveJournal of Oral and Maxillofacial SurgeryVol. 62Issue 12PreviewDamage to the inferior alveolar nerve when extracting lower third molars is often caused by the intimate relationship between the nerve and the roots of the teeth. The technique of coronectomy, or intentional root retention, may minimize this problem. Full-Text PDF