Benefits of Coronectomy in Lower Third Molar Surgery: A Systematic Review and Meta-analysis.

PURPOSE: The purpose of this study was to measure and compare coronectomy versus extraction in patients at increased risk for inferior alveolar nerve (IAN) injuries associated with third molar removal in terms of IAN injury and other complications. METHODS: The review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-analyses checklist. We conducted a comprehensive literature search across six databases and the gray literature from July 15 to August 01, 2022. We employed Rayyan software to identify and remove duplicate articles to ensure data integrity. Our research followed the strategy patient (P), intervention (I), comparison (C), outcome (O), and study (S): (P) patients needing lower third molar surgery at higher risk of IAN injury; (I) surgery options, coronectomy or complete extraction; (C) comparisons included reduced risks of nerve injuries, postoperative complications (pain, infection, alveolitis), and increased risks of reoperation, root migration, and extraction; (O) desired outcomes were preventing nerve injuries and reducing other surgical complications; and (S) observational study designs (cohort, case-control). Excluded from consideration were studies involving teeth other than lower third molars, as well as reviews, letters, conference summaries, and personal opinions. To gauge the certainty of evidence, we employed the Grading of Recommendation, Assessment, Development, and Evaluation instrument, selecting the most current papers with the highest levels of evidence for inclusion. The primary outcome variable of our study centered on evaluating the incidence of IAN injury, and secondly, the lingual nerve (LN) injury, the postoperative pain, infection, localized alveolitis, the necessity for surgical reintervention, root migration, and extraction. These assessments were carried out with respect to their chosen operative technique for managing third molars, either coronectomy or extraction, as predictor variables. We also considered covariates such as age, gender, and the presence of systemic diseases in our analysis to account for potential confounding factors. The pooled data underwent rigorous analysis utilizing an inverse variance method with both random and fixed effect models by the "metabin" function in the R program's meta-package. Additionally, we assessed the risk of bias in the selected studies by utilizing the Joanna Briggs Institute's Critical Appraisal Checklist for Studies Reporting Prevalence Data and the Critical Appraisal Checklist for Case Reports. RESULTS: Of the 1,017 articles found, after applying the inclusion and exclusion criteria, 42 were included in this study (29 cohort and 13 case-control studies), including 3,095 patients from 18 countries. The meta-analysis showed that coronectomy reduced the risk of IAN injury [OR (Odds Ratio): 0.14; 95% CI (confidence intervals): 0.06-0.30; I2 (inconsistency index) = 0%; P = .0001], postoperative pain (OR: 0.97; 95% CI: 0.33-2.86; I2 = 81%; P = .01), and alveolitis (OR: 0.38; 95% CI: 0.13-1.09; I2 = 32.2%; P = .01) when compared to complete tooth extraction. However, it also highlighted a greater risk of reintervention (OR: 5.38; 95% CI: 1.14-25.28; I2 = 0.0%; P = .01). CONCLUSIONS: This study has demonstrated that coronectomy is associated with a decreased risk for IAN injury and decreased pain and localized alveolitis when compared to complete tooth extraction. However, it is essential to acknowledge the higher likelihood of requiring reintervention with coronectomy. Therefore, clinicians should carefully consider the advantages and potential drawbacks of both techniques and tailor their choices to the unique clinical circumstances of each patient.

Indications for root canal treatment following traumatic dental injuries to permanent teeth.

The dental pulp may respond favourably or unfavourably to traumatic dental injuries. The most serious unfavourable responses are pulp necrosis and infection of the root canal system. These cause apical periodontitis and/or external inflammatory resorption of the tooth. The following injuries require root canal treatment as part of their emergency management-(A) complicated crown fractures (but some may be suitable for conservative pulp treatments, such as pulp capping, partial pulpotomy or pulpotomy), (B) complicated crown-root fractures, (C) supra-crestal coronal third root fractures and (D) injuries where pulp necrosis is predictable or highly likely to occur AND where there has been damage to the root surface and/or periodontal ligament with the aim of preventing external inflammatory resorption. This latter group of injuries are avulsion, intrusion, lateral luxation with a crown fracture, extrusion with a crown fracture (all in fully developed teeth) plus avulsion with a crown fracture and intrusion with a crown fracture (both in incompletely developed teeth). All other injuries should not have root canal treatment commenced as part of the emergency management, but they must be reviewed regularly to monitor the pulp for any adverse changes to its status, particularly pulp necrosis and infection of the root canal system.

The effect of individual drilling sleeves on the precision of coronectomy tooth sections. An in vitro 3D-printed jaw model experiment.

OBJECTIVES: The aim of this in vitro study was to evaluate the effect of a 3D-printed drill sleeve (DS) on the precision and duration of coronectomy sections. MATERIALS AND METHODS: Thirty-six trainees and oral surgeons performed 72 coronectomy cuts in a 3D-printed, entirely symmetric mandible model. Coronectomy was performed freehand (FH) on one side and with a DS on the other side. The occurrence of "too superficial" (≥ 4 mm unprepared lingual tooth tissue) and "too deep" (drilling ≥ 1 mm deeper as tooth contour) cuts and sectioning times were registered. RESULTS: In 7 cases, the sections were "too deep" with FH, while none with DS (OR: 18.56; 95%CI: 1.02-338.5; p = 0.048). The deviation between virtually planned and real cut depths was significantly greater in the FH group (1.91 ± 1.62 mm) than in DS group (1.21 ± 0.72 mm) (p < 0.001). A total of 18 "too superficial" buccolingual sections occurred with FH, while 8 cases with DS (OR: 3.50; 95%CI: 1.26-9.72; p = 0.016). Suboptimal sections did not correlate with experience (p = 0.983; p = 0.697). Shortest, suboptimal drillings were most frequently seen distolingually (OR: 6.76; 95% CI: 1.57-29.07; p = 0.01). In the inexperienced group, sectioning time was significantly longer with FH (158.95 ± 125.61 s vs. 106.92 ± 100.79 s; p = 0.038). CONCLUSIONS: The DS effectively reduced tooth sectioning times by less experienced colleagues. Independently from the level of experience, the use of DS obviated the need for any preparation outside the lingual tooth contour and significantly decreased the occurrence of "too superficial" cuts, leaving thinner unprepared residual tooth tissue lingually. CLINICAL RELEVANCE: Coronectomy sections may result in lingual hard and soft tissue injury with the possibility of damaging the lingual nerve. The precision of the buccolingual depth-control can be improved, while surgical time can be reduced when applying a drilling sleeve.

[How long does a tooth last after a surgical crown lengthening?] / Hoe lang gaat een gebitselement mee na een chirurgische kroonverlenging?

The presence of subgingival pathology, such as a deep secondary caries lesion, a fracture, an already existing restoration that needs to be replaced or the presence of a resorption defect, can constitute a difficult starting situation for the preservation of a tooth. How to deal with such a situation has been a topic of discussion for years. Surgical crown lengthening is one of the first and classic treatment options that is often chosen in such cases. Crown lengthening is a periodontal surgical technique to obtain extra supra crestal clinical crown length. The question is, what is the long-term prognosis of teeth after surgical crown lengthening. To answer this question, a review of the literature was carried out looking for clinical studies examining survival. Four studies with a follow-up of at least 5 years were included. The factors that adversely affect survival of the tooth after the crown lengthening are an unfavourable crown-root ratio, insufficient plaque control and moderate ability to keep the restoration clean.

What is the Incidence of Late Complications Associated With Lower Third Molar Coronectomy? 10-Year Follow-Up Results.

PURPOSE: Coronectomy is an operation to manage impacted third molars (M3s) considered at high risk for mandibular nerve injury but long-term outcomes are still lacking. The purpose of this study was to estimate the risk of late complications occurring within 10 years following lower M3 coronectomy. METHODS: The investigators designed a prospective cohort study and enrolled a sample of 94 patients treated with coronectomy of third mandibular molars at the Unit of Oral and Maxillofacial Surgery of the University of Bologna, from 2009 to 2012. This follow-up study included all of the patients from the original study who completed 10 years of follow-up. The primary outcome variables is postoperative late complication occurring between 5 and 10 years after coronectomy coded as present or absent. Late complications were defined as root exposure, nerve injury, pulpitis, periapical infection, and reoperation. The secondary outcome variable was probing pocket depth. Covariates examined were age, smoking and type of M3 impaction. Descriptive statistical analyses were performed. RESULTS: The inception cohort was composed of 94 subjects who had 116 coronectomies (k) completed. The study cohort was composed of subjects with 10 years of follow-up and included 48 subjects (k = 60) with a mean age of 28.99 ± 8.9 years. Between years 5 and 10 of follow-up, 2 subjects (4%) have complications; all root exposures diagnosed at years 8 or 9 after surgery. In another case root removal was required for orthodontics reason. No case of nerve injury to the inferior alveolar nerve occurred, and no periapical infection was observed around the residual roots. The mean 10-year probing pocket depth was 3.31 ± 0.92 mm (1,66-5,66 mm). There were too few complications to identify risk factors for late complications. CONCLUSIONS: Within all the limitations of this study, the results of this prospective study imply that coronectomy is a useful surgical technique for the treatment of M3s at high neurological risk, to avoid nerve injury to the inferior alveolar nerve. In addition, after coronectomy, retained roots did not develop late infection or periapical infection in the long term. However, in a few cases, removal of retained roots was required at 10 years, due to root migration in the oral cavity. The risk for late complications is uncommon, but persistent.

Management of Crown-root Fracture with 180-degree Rotation Replantation: a Report of 2 Cases.

Intentional replantation involves a combination of periodontics, endodontics, prosthodontics and oral surgery. Crown-root fracture management is still complicated nowadays. A fracture line extending longitudinally to the subgingival area and intruding bioogical width could affect infection control, gingival health and crown restoration. In the present study, we present two cases. Case 1 involved a 23-year-old man who presented at our hospital with crown-root fracture of the maxillary left central incisor. A radiographic image of the tooth revealed a fracture line under the alveolar crest. The fractured tooth was treated with intentional replantation with 180-degree rotation, root canal treatment and veneer restoration. The patient was followed up for 60 months. The replanted tooth functioned well, and no symptoms of resorption or ankylosis were observed by radiographic examination. Case 2 involved a 20-year-old woman who was referred to our hospital for crown-root fracture of her maxillary teeth. A radiographic examination revealed complicated crown-root fracture of the maxillary right lateral incisor and both maxillary central incisors. The central incisors were treated with intentional replantation with 180-degree rotation. At the 48-month follow-up, the fractured teeth were found to have regained normal function based on clinical and radiographic examination. Limited case reports are available on a long-term follow-up of intentional replantation with 180-degree rotation. These two cases, particularly case 2, presented optimal healing after 4 years with unideal crown-root ratios. This case report suggests that this old method of preserving teeth with crown-root fractures can be used as a last resort to save teeth owing to its timesaving and microinvasive procedure.

Comparative Study of Two Ways to Measure Root Trunk Length to Assess the Possibility of Crown Lengthening in Molars: Measuring Parallel to the Root Surface vs Parallel to the Tooth Axis

The aim of this study was to compare root trunk measurements taken parallel to the tooth axis (TA) to those taken parallel to the root surface (RS) in order to assess the decision-making implications of each method on crown-lengthening surgery. A total of 672 root trunks were measured via CBCT in two planes: TA and RS. The possibility of performing crown lengthening in each clinical situation based on the distance from the cementoenamel junction (CEJ) to the crestal bone (CB) after ostectomy (CEJ-CB) was judged and compared between groups. When RS was used as a reference point, the proportions of cases that judged crown lengthening to be possible were 83.63%, 59.08%, and 39.18% for CEJ-CB values of 4, 5, and 6 mm, respectively. When TA was used instead, those proportions decreased by 3.87% to 7.29%. The lingual root trunk of the lower first molar (LFL) with a CEJ-CB of 4 to 5 mm emerged as the most problematic area; here, the difference between reference planes occurred with one out of every six teeth. Within the limits of this study, utilizing TA for surgical crown-lengthening treatment planning is not ideal because it may lead to extraction of many savable teeth.

New approach to expedite the delivery of the final crowns for teeth requiring crown lengthening surgery: a pilot study.

BACKGROUND: The healing period from crown lengthening procedures (CLPs) often delays the final crown delivery. This study aimed to explore the feasibility of a new approach expediting the delivery of the final crowns for teeth requiring CLPs. METHODS: Teeth requiring CLPs and single-crown restorations between the canine and the second molar were included. After the initial tooth preparation, a CLP was performed. In the experimental group, the final tooth preparation and final impression were made during the CLP; the final crown was then delivered at the suture-removal appointment. In the control group, the final impression was made 8 weeks after the CLP. The level of gingival margin (GM), pocket depth (PD), and crestal bone levels (CBLs) were compared between the two groups before CLPs (T0), at delivery of the crowns (T1), and at 12 months in function (T2). RESULTS: Twenty-one lithium-disilicate crowns were delivered to 20 subjects and followed up. The mean interval between the CLPs and the delivery of crowns was 2.5 weeks for the experimental group and 12 weeks for the control group. No significant differences were observed between the two groups in the level of GM, PD, and CBLs at each time point. No significant treatment difference in crestal bone loss was observed between the two groups at T2 (Experimental = -0.11 mm, Control = -0.03 mm; p = 0.67). CONCLUSION: Making the final tooth preparation and the final impression at the CLP significantly reduced the time between the CLP and the delivery of the final crown and showed comparable clinical outcomes.

Coronectomy: An Alternative to Complicated Full-Bony Impacted Tooth Removal.

The removal of impacted teeth is a common office-based oral and maxillofacial surgical procedure. Complications associated with the procedure are uncommon; however, in the mandible, close proximity of the third molars to the inferior alveolar nerve can potentially lead to temporary or permanent sensory disturbances. The intentional partial odontectomy (coronectomy) procedure is a surgical option aimed at mitigating and reducing the incidence of this potential risk and complication.

Success rate of fractured teeth receiving modified crown lengthening surgery and restorations.

BACKGROUND: Whether to preserve a structurally compromised tooth or remove it is a dilemma often encountered by clinicians. The aim of this study was to assess the long-term success rate of fractured teeth preserved by modified crown lengthening surgery and restorations. METHODS: Thirty-nine patients with a total of 45 fractured teeth who had received modified crown lengthening surgery were recruited and examined. Numbers of teeth lost were recorded, and the criteria for successful teeth were defined. Kaplan-Meier estimator was used to determine the success rate. Possible risk factors were compared between successful and unsuccessful groups by a Cox regression analysis to explore the potential predictors of failure with a significant level at α = 0.05. RESULTS: The mean ± SD of success time without considering variants was 6.2 ± 0.6 years (95% CI 5.1-7.7). The mean survival rates ± SD at 1.0-, 2.0-, 3.0-, 5.0-, 7.0-, and 9.0-year intervals was 97.8 ± 2.2%, 92.2 ± 4.4%, 72.8 ± 7.9%, 68.2 ± 8.6%, 60.7 ± 10.5%, and 40.4 ± 13.6%, respectively. Failure cases in teeth with poor plaque control and step-shaped fracture margin were significantly more than those with good plaque control and knife-shaped fracture margin (HR = 7.237, p = 0.011; HR = 15.399, p = 0.006; respectively). CONCLUSIONS: Fractured teeth treated with modified crown lengthening surgery are anticipated to have a high clinical success rate for 6.2 ± 0.6 years. Plaque control and fracture morphology appeared to be significantly associated with the success of the multidisciplinary treatment approach.

Flapless Decoronation: A Minimally Invasive Approach.

Traumatic injuries to the permanent dentition are most common in children. In severe dentoalveolar injuries, especially avulsion and intrusion, dentoalveolar ankylosis is a common complication, leading to adverse effects on the developing alveolar bone and interfering with the eruption of the adjacent teeth. The decoronation procedure was suggested in 1984 to reduce these side effects related to ankylosis. The objective of the current publication is to describe a minimally invasive, flapless decoronation procedure aimed to minimize and simplify the surgical procedure of decoronation, and ease its clinical acceptance, particularly in young children. The technique is described in a detailed protocol and demonstrated in two cases. Under local anesthesia, the dental crown is removed, and the root is reduced by 1.5-2.0 mm apically to the marginal bone crest. The root canal content is then removed, allowing it to fill with blood. The socket is coronally sealed with a porcine-derived collagen matrix (PDCM) sutured using the "parachute" technique over the resected root, allowing close adaptation to the surrounding soft tissue. In conclusion, the presented technique of flapless decoronation is a modification of the classic decoronation procedure, which can be used as a minimally invasive technique to simplify the surgical procedure and the post-operative process.

Displacement of the Inferior Alveolar Bundle Secondary to Post Coronectomy Root Migration: A Case Report.

Intentional coronectomy has become a commonplace procedure as an alternative to full third molar removal in order to decrease the occurrence of inferior alveolar nerve (IAN) injury. It is well known that one of the sequelae of this procedure is superior root migration. This is usually not a significant problem as the migrated roots may erupt to a position where they are more readily removed. This report presents a case in which a curvature at the apex of the root displaced the IAN causing neurologic symptoms.

Factors affecting root migration after coronectomy of the mandibular third molar.

ABSTRACT: Nerve injury especially inferior alveolar nerve (IAN) is the one of the complications that occur when the mandibular third molar (M3) is extracted and in case of high risk patients, coronectomy might be an alternative to tooth extraction. The purpose of this retrospective study was to analyze root migration and its influencing factors at 6 months after coronectomy in both 2- and 3-dimensions using periapical view and cone-beam computed tomography (CBCT). We analyzed 33 cases of root remnant after coronectomy and measured the amount of migration in CBCT. The following factors that could possibly affect root migration were also analyzed: age, gender, number of M3 roots, shape of M3s, Pell, and Gregory classification, mesiodistal (MD) angulation, buccolingual (BL) angulation, contact point with the second molar, root curvature, and complete removal of the coronal portion. Migration of greater than 2 mm was found in 64% of the roots in the 2-dimensional (2D) analysis, and the average root migration was 4.11 mm in the 3-dimensional (3D) analysis. The factors affecting migration were the root morphology, complete removal of the coronal portion, impaction depth, and MD angulation in the 2D analysis, and MD and BL angulation in the 3D analysis. Ensuring sufficient space for root migration especially considering angulation, depth and complete removal of the coronal portion might be important factors after coronectomy of the M3. Root remnant after coronectomy of M3 may migrate in young patients who has sufficient empty coronal space and this may reduce the nerve damage by the separation of IAN and M3.

The management of a complicated crown-root fracture incorporating modified crown-lengthening surgery.

Anterior teeth with subgingival fractures require a multidisciplinary management approach with regards to biological, functional and aesthetic factors. This case report emphasises the use of a minimally invasive technique combined with a sequence of therapies to treat a complicated crown-root fracture and reviews the critical factors to ensure predictable outcomes. Endodontic treatment was undertaken due to exposure of the pulp in a complicated crown-root fracture of the maxillary right central incisor. Extrusion of the fractured fragment was performed to expose the fracture margin under the alveolar bone. Modified crown-lengthening surgery was used to reconstruct the biologic width. The traumatised tooth was restored with a glass fibre post and resin core, which fit the biological requirements. Finally, an all-ceramic crown fulfilled biomimetic aesthetics. This multidisciplinary approach achieved a good long-term prognosis with regards to periodontal and periapical healing.

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

BACKGROUND: 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. METHODS: 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 6 months follow-up were included. RESULTS: 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. CONCLUSIONS: 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.

Coronectomia: alternativa à exodontia de terceiros molares inferiores / Coronectomy: an alternative to third lower molar extraction

Objetivo: relatar um caso clínico de coronectomia com acompanhamento pós-operatório de 15 meses. Relatode caso: a coronectomia é uma alternativa de tratamento para terceiros molares inferiores (3MI) impactadosque apresentam proximidade com o canal mandibular, minimizando o risco de morbidade neurossensorial.A técnica consiste em remover apenas a coroa dentária (na junção amelocementária) com retençãointencional das raízes e da polpa, evitando o dano direto ou indireto ao nervo alveolar inferior (NAI). Oprocedimento foi realizado em paciente adulto do gênero masculino com 3MI impactados. A radiografia panorâmicamostrava o escurecimento dos ápices radiculares, sugerindo íntima relação das raízes com o canalmandibular. No acompanhamento pós-operatório imediato, o paciente retornou sem sintomatologia dolorosa,sem edema facial significativo, apresentando boa cicatrização e sem relato de perda de sensibilidade nemde disfunção mastigatória. No acompanhamento radiográfico, foi verificada neoformação óssea adjacenteaos remanescentes radiculares. Considerações finais: a coronectomia mostrou-se um procedimento simples,eficaz e seguro para diminuir o risco de injúria ao NAI durante o tratamento dos 3MI.(AU)

Objective: to report a case of coronectomy with follow-up of 15 months. Case report: coronectomy is an alternative treatment for impacted lower third molars (3ML) which are close to the mandibular canal, minimizing the risk of sensorineural morbidity. The technique consists of removing only the dental crown (at the cementoenamel junction) with intentional retention of the roots and pulp, avoiding direct or indirect damage to the inferior alveolar nerve (IAN). The procedure was performed on an adult male patient with impacted 3ML. Panoramic radiograph showed darkening of the roots, suggesting a close relationship between the roots and the mandibular canal. At immediate postoperative follow-up, the patient returned with no painful symptoms, no significant facial edema, good healing, and no loss of sensation or masticatory dysfunction. Radiographic follow-up showed bone neoformation adjacent to the root remnants. Final considerations: coronectomy has been shown to be a simple, effective and safe procedure to decrease the risk of injury to IAN during 3MI treatment.(AU)

Planejamento digital para cirurgia de aumento de coroa clínico estético: relato de caso / Digital planning for aesthetic clinical crown increase surgery: case report

A exposição excessiva de gengiva durante o sorriso é denominada como sorriso gengival. O fator etiológico dessa alteração é variado e sua identificação é fundamental para confecção de um plano de tratamento eficaz. O planejamento clínico pode ser realizado utilizando uma abordagem dinâmica e digital do sorriso. Sendo assim, software, exames imaginológicos, modelo virtual 3D e guia cirúrgico aumentam a qualidade e a precisão do tratamento, trazendo inúmeros benefícios para o paciente. Objetivo: demonstrar a importância do fluxo digital no planejamento e na correção do sorriso gengival. Relato de caso: paciente apresentou queixas em relação ao tamanho dos dentes e ao excesso de exposição de gengiva durante o sorriso. Após exames clínico e radiográfico, foi possível realizar o diagnóstico do fator etiológico como erupção passiva alterada (EPA). O tratamento de escolha foi o recontorno gengival associado à realização de osteotomia e osteoplastia. Para uma maior precisão do tratamento, foi confeccionado um guia cirúrgico duplo. Após o procedimento, a paciente foi orientada e medicada. Considerações finais: a abordagem digital do sorriso favoreceu um tratamento cirúrgico preciso, eficaz e satisfatório para a paciente, reestabelecendo assim a harmonia dento-gengivo-facial.(AU)

Excessive gum exposure during a smile is called a gum smile. The etiologic factor of this alteration is varied, the identification is essential to create an effective treatment plan. Clinical planning can be performed using a dynamic and digital smile approach. Therefore, software, imaging tests, 3D virtual model and the surgical guide increase the quality and precision of the treatment thus bringing numerous benefits to the patient. Objective: this case report aims to demonstrate the importance of digital flow in smile planning and correction of a gum smile. Case report: the patient presented complaints regarding tooth size and excessive gum exposure during the smile. After the clinical and radiographic examination, the etiological factor was diagnosed as an altered passive eruption (APE). The treatment of choice was the gingival contour associated with osteotomy and osteoplasty. For the precision of the treatment, a double surgical guide was made. After the procedure the patient was guided and medicated. Conclusion: the digital smile approach favored an accurate, effective and satisfactory surgical treatment for the patient thus restoring the tooth-gingival-facial harmony.(AU)

Coronectomía en terceros molares inferiores / Coronectomy of the lower third molar

La extracción del tercer molar inferior es el procedimiento más frecuente dentro del campo de la cirugía bucal, siendo el daño del nervio dentario inferior una de las complicaciones más frecuentes en la extracción. Como alternativa para disminuir el riesgo de aparición de esta complicación surge la coronectomía, técnica que consiste en la eliminación de la corona dentaria manteniendo intactas las raíces dentro del hueso alveolar. El objetivo del presente artículo fue realizar una puesta al día sobre la coronectomía en terceros molares inferiores, analizando indicaciones, contraindicaciones, complicaciones y éxito de esta técnica. La coronectomía parece ser una alternativa eficaz a la extracción para la prevención de trastornos neurosensoriales en terceros molares impactados en estrecha relación con el NDI. Sin embargo, es necesaria la realización de más estudios comparando la extracción convencional con la coronectomía, con un mayor seguimiento, para conocer el éxito y las complicaciones a largo plazo de este tratamiento

The lower third molar extraction is one of the most common procedures in the field of oral surgery. Furthermore, the damage of the inferior alveolar nerve is one of the most frequent complications related to this procedure. The coronectomy was introduced in 1984, as an alternative approach that tended to reduce the occurrence of this complication. The main objective of this article is to review current evidence of coronectomy applied to mandibular third molars, analyzing indications, contraindications, complications and success of the technique. The coronectomy seems to be an effective alternative to conventional third molar extraction, for the prevention of neurosensorial disorders in impacted third molars in direct relation with inferior alveolar nerve. However, further studies are needed which compare conventional approach with coronectomy with a greater follow-up to understand the long-term morbidities and success of the technique

Actitud terapéutica frente a una reabsorción interna perforante / Therapeutic attitude against a perforating internal resorption

Atendiendo a la localización de la reabsorción radicular, ésta puede ser clasificada en externa o interna. La reabsorción interna es relativamente poco frecuente, y su etiología y patogénesis no está todavía del todo clara. Este artículo muestra la complejidad de un incisivo central superior con una reabsorción interna inflamatoria perforante. El diagnóstico definitivo lo hallamos a través del examen tridimensional, que confirmó la extensión y comunicación con la superficie externa radicular. Aunque como podremos ver a lo largo de la exposición del caso clínico, la ayuda del microscopio nos permitió abordar el caso con mayor seguridad. En todo momento pudimos eliminar el tejido inflamatorio y preparar el conducto de manera adecuada. La obturación en este tipo de casos supone un reto para el endodoncista, siendo éste, mayor cuando se realiza únicamente de manera ortógrada. Para la obturación realizamos una técnica descrita en la literatura, sellando la zona apical a la reabsorción con gutapercha adaptada mediante condensación vertical; la zona reabsortiva con material biocerámico y, por último, la zona coronal con guta-percha inyectada. Se realizó un 3D a los 26 meses para una nueva evaluación de la zona reabsortiva, y así evaluar el estado óseo alrededor de la misma. La paciente se presenta totalmente asintomática sin signos clínicos y con buena salud de los tejidos periapicales

Based on the location of the root resorption, it can be classified as external or internal. Internal resorption is relatively rare, and its etiology and pathogenesis is not yet entirely clear. This article shows the complexity of a superior central incisor with a perforating inflammatory internal resorption. The definitive diagnosis is found through the three-dimensional examination, which confirmed the extension and communication with the external root surface. Although as we can see throughout the presentation of the clinical case, the help of the microscope allowed us to address the case with greater certainty. At all times we were able to remove the inflammatory tissue and prepare the duct properly. The obturation in this type of cases supposes a challenge for the endodontist, being this one, greater when it is done only in an ortograde way. For the filling, we performed a technique described in the literature, filling the apical area with resorption with gutta-percha adapted by vertical condensation; the resorptive zone with bioceramic material and finally the coronal zone with injected gutta-percha. A 3D was performed at 26 months for a new evaluation of the resorptive zone, and thus evaluate the bone state around it. The patient presents totally asymptomatic without clinical signs and with good health of the periapical tissues

A systematic review of the complications of high-risk third molar removal and coronectomy: development of a decision tree model and preliminary health economic analysis to assist in treatment planning.

Coronectomy is an alternative surgical technique for the management of high-risk third molars. It involves the removal of the crown of a tooth and the deliberate retention of the roots, thereby avoiding injury to the inferior alveolar nerve (IAN). Previous studies have suggested that it reduces the risk of nerve injury when compared with surgical extraction. The purpose of this study was to systematically review the incidence of complications following coronectomy such as IAN injury, pain, dry socket, infection, root migration, and need for re-operation. A comparative cost analysis of coronectomy and surgical extraction was done based on the results of the review. This provides an insight into the economic implications of the two procedures. A search through the MEDLINE database via Ovid, PubMed, Scopus, EMBASE via Ovid, and Web of Science, was carried out to extract randomised and non-randomised controlled trials. Four studies fulfilled the inclusion criteria. A meta-analysis was conducted to measure the overall effect of each outcome. The pooled odds ratio (OR) for IAN injury was 0.16 (95% CI 0.01 to 0.39). Coronectomy reduced this risk by 84%. Dry socket may occur less frequently following coronectomy whereas infection did not show a higher incidence with either intervention. Root migration was found to occur in 13%-85% of cases and the average incidence of re-operation was 2.2%. The ratio of the average costs was 1.12 favouring coronectomy if cone-beam computed tomography (CBCT) was not done prior to the procedure. If a scan was taken routinely for coronectomy, the cost ratio marginally favoured extraction. Coronectomy reduced the risk of nerve injury in high-risk third molars. Definitive conclusions, however, cannot be made for outcomes such as the need for re-operation, which may alter the cost ratio of coronectomy:extraction, as higher quality studies with longer follow-up are needed.