Management of Recurrence of Ameloblastoma and Odontogenic Keratocyst: A Cross-Sectional Study / Manejo de la recurrencia del ameloblastoma y keratoquiste odontogénico: Estudio de corte transversal

Abstract Objectives: Odontogenic keratocyst (OKC) and ameloblastoma are slowly growing and locally invasive tumors with high recurrence rate. The aim of this study was to investigate the clinicopathologic features of recurrent ameloblastoma and OKC cases, and evaluate outcomes of our treatments in terms of recurrence. Material and Methods: A total of 23 patients with confirmed recurrent ameloblastoma or OKC and treated in our clinic within eleven years period were reviewed retrospectively. Results: Eleven recurrent OKC cases and twelve recurrent ameloblastoma cases were included. Most recurrences occurred within five years after the initial treatment (69.6%). Enucleation had the highest recurrence rate among the first treatments (18/23). All recurrences were located in the mandible, with one exception (22/23). All recurrent OKCs were multilocular. Different histopathologic subtypes of ameloblastoma were seen in our study, follicular ameloblastoma was the most common (8/12). The mean diameter of the lesions was 4.3 cm (ranging from 2 cm to 7 cm). Statically significant relation was found between location and diameter of lesion and year of recurrence onset (p=0.004; p=0.026). We performed radical treatments in these cases (ten patients underwent marginal resections, and thirteen patients underwent segmental resection), and no recurrence was observed during the follow-up period. Conclusion: Previous inadequate surgical procedures were the most important cause of recurrence. Marginal or segmental resection with safety margins is the best method to treat recurrences of OKC or ameloblastoma cases.

Resumen Objetivo: Los keratoquistes odontogénicos (KQO) y ameloblastomas son tumores invasivos de lento crecimiento local con una alta tasa de recurrencia. El propósito de este estudio fue investigar las características clínico patológicas de los casos de ameloblastoma y KQO recurrentes y evaluar los resultados de tratamientos en término de recurrencia. Materiales y Métodos: Un total de 23 pacientes con casos confirmados de ameloblastomas o KQO recurrentes tratados en nuestra clínica en un período de once años fueron incluidos. Resultados: Once casos de KQO recurrentes y doce ameloblastomas recurrentes fueron incluidos. La mayoría de las recurrencias ocurrieron en los primeros 5 años posteriores al tratamiento inicial (69.6%). La enucleación mostró la tasa de recurrencia más alta entre los tratamientos iniciales (18/23). Todas las recurrencias se presentaron en la mandíbula excepto por un caso (22/23). Todos los KQO fueron multiloculares. Distintos subtipos histológicos del ameloblastoma fueron detectados en el estudio y el ameloblastoma folicular fue el más común (8/12). El diámetro promedio de las lesiones fue de 4.3cm en un rango de 2cm a 7cm. Una relación estadísticamente significativa se encontró entre la ubicación y el diámetro de la lesión y el tiempo de aparición de la recurrencia (p=0.004; p=0.026). Se realizaron tratamientos radicales en los siguientes casos, diez pacientes tuvieron resecciones marginales y trece pacientes resección segmental; no se observaron recurrencias en el período de seguimiento. Conclusión: Procedimientos previos inadecuados fueron la causa más relevante de recurrencia. Resección marginal o segmental con márgenes de seguridad son el mejor método para tratar casos de ameloblastoma y KQO recurrentes.

Multidisciplinary approaches to odontogenic lesions.

PURPOSE OF REVIEW: To give an overview of technical considerations and relevant literature in the management odontogenic pathology with involvement of the maxillary sinus. RECENT FINDINGS: Infections, cysts, benign neoplasms (odontogenic and nonodontogenic), and inflammatory conditions impact the maxillary sinus in various ways, could result in significant expansion within the maxillary sinus and significant infections. SUMMARY: This manuscript provides an overview of common pathologic entities of the oral cavity proper that impacts the maxillary sinus health, with discussion of the role of the otorhinolaryngologist and the dental specialist.

[Clinical and imaging features of 36 odontogenic keratocysts associated with an impacted tooth].

PURPOSE: To analyse the imaging features of odontogenic keratocysts (OKCs) associated with an impacted tooth. METHODS: Clinical and radiological data of 235 cases with OKCs were respectively investigated, with emphasis on imaging features of 36 OKCs, which were associated with an unerupted tooth. RESULTS: In 36 cases of OKCs associated with an impacted tooth, the ratio of male to female was 1.77:1, and molar-ramus was involved in 26 cases (72.22％). OKCs in association with an unerupted tooth occurred mostly in patients ranging from 20 to 30 years (19 cases, 52.8％). There were 27 cases (75％) of unilocular and 9 cases (25％) multilocualr radiolucency. Thirteen cases (36.11%) were related to the crown of the impacted teeth, and the unerupted teeth also were impacted as a result of malposition in which the entire teeth appeared to be enveloped by cysts (15 cases, 41.67%), or adjacent to cyst wall (8 cases, 22.22%). CONCLUSIONS: Radiographically, one of the most imaging features of OKCs in association with an unerupted tooth is that its entire tooth appears to be enveloped by cyst or adjacent to cyst, while pericoronal radiolucencies surrounding an impacted tooth are rarely seen.

Effect of the sonic hedgehog inhibitor GDC-0449 on an in vitro isogenic cellular model simulating odontogenic keratocysts.

Odontogenic keratocysts (OKCs) are common cystic lesions of odontogenic epithelial origin that can occur sporadically or in association with naevoid basal cell carcinoma syndrome (NBCCS). OKCs are locally aggressive, cause marked destruction of the jaw bones and have a propensity to recur. PTCH1 mutations (at ∼80%) are frequently detected in the epithelia of both NBCCS-related and sporadic OKCs, suggesting that PTCH1 inactivation might constitutively activate sonic hedgehog (SHH) signalling and play a major role in disease pathogenesis. Thus, small molecule inhibitors of SHH signalling might represent a new treatment strategy for OKCs. However, studies on the molecular mechanisms associated with OKCs have been hampered by limited epithelial cell yields during OKC explant culture. Here, we constructed an isogenic PTCH1R135X/+ cellular model of PTCH1 inactivation by introducing a heterozygous mutation, namely, c.403C>T (p.R135X), which has been identified in OKC patients, into a human embryonic stem cell line using the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) system. This was followed by the induction of epithelial differentiation. Using this in vitro isogenic cellular model, we verified that the PTCH1R135X/+ heterozygous mutation causes ligand-independent activation of SHH signalling due to PTCH1 haploinsufficiency. This activation was found to be downregulated in a dose-dependent manner by the SHH pathway inhibitor GDC-0449. In addition, through inhibition of activated SHH signalling, the enhanced proliferation observed in these induced cells was suppressed, suggesting that GDC-0449 might represent an effective inhibitor of the SHH pathway for use during OKC treatment.

Abordaje quirúrgico conservador para el tratamiento del queratoquiste odontogénico / Conservative surgical approach for the treatment of odontogenic keratocyst

Introduction: The odontogenic keratocyst was recently reclassified in 2017 by the World Health Organization as a cystic lesion of epithelial development derived from the enamel organ or the dental lamina. It shows common characteristics to cysts such as slow and continuous growth; however, it arouses attention for its high aggressiveness and recurrence rate. Objective: To show marsupialization followed by enucleation as a definitive treatment of odontogenic keratocysts. Clinical case: A 63-year-oldwoman with odontogenic keratocyst on the left side of the mandible, treated by the marsupialization technique followed by enucleation. Conclusions: Although there are various treatment options, the dental surgeon may prefer the conservative method in the approach of the odontogenic keratocyst, because it presents the lowest rate of morbidity and relapse within the standards presented in the literature(AU)

Introducción: el queratoquiste odontogénico fue reclasificado en 2017 por la Organización Mundial de la Salud como una lesión cística de desarrollo epitelial, derivado del órgano del esmalte o de la lámina dental. Presenta características comunes a quistes, como crecimiento lento y continuo, sin embargo, llama la atención por su alta agresividad y tasa de recurrencia. Objetivo: describir la marsupialización seguida de enucleación como un tratamiento definitivo para el queratoquiste odontogénico. Presentación del caso: mujer de 63 años con queratoquiste odontogénico en el lado izquierdo de la mandíbula, tratado por la técnica de marsupialización seguido de enucleación. Conclusiones: a pesar de diferentes opciones de tratamientos existentes, el método conservador puede ser el tratamiento de elección del cirujano-dentista en el abordaje del queratoquiste odontogénico, pues presenta la menor tasa de morbilidad y recidiva dentro de los patrones mostrados en la literatura(AU)

Abordaje quirúrgico conservador para el tratamiento del queratoquiste odontogénico / Conservative surgical approach for the treatment of odontogenic keratocyst

Introduction: The odontogenic keratocyst was recently reclassified in 2017 by the World Health Organization as a cystic lesion of epithelial development derived from the enamel organ or the dental lamina. It shows common characteristics to cysts such as slow and continuous growth; however, it arouses attention for its high aggressiveness and recurrence rate. Objective: To show marsupialization followed by enucleation as a definitive treatment of odontogenic keratocysts. Clinical case: A 63-year-oldwoman with odontogenic keratocyst on the left side of the mandible, treated by the marsupialization technique followed by enucleation. Conclusions: Although there are various treatment options, the dental surgeon may prefer the conservative method in the approach of the odontogenic keratocyst, because it presents the lowest rate of morbidity and relapse within the standards presented in the literature(AU)

Introducción: el queratoquiste odontogénico fue reclasificado en 2017 por la Organización Mundial de la Salud como una lesión cística de desarrollo epitelial, derivado del órgano del esmalte o de la lámina dental. Presenta características comunes a quistes, como crecimiento lento y continuo, sin embargo, llama la atención por su alta agresividad y tasa de recurrencia. Objetivo: describir la marsupialización seguida de enucleación como un tratamiento definitivo para el queratoquiste odontogénico. Presentación del caso: mujer de 63 años con queratoquiste odontogénico en el lado izquierdo de la mandíbula, tratado por la técnica de marsupialización seguido de enucleación. Conclusiones: a pesar de diferentes opciones de tratamientos existentes, el método conservador puede ser el tratamiento de elección del cirujano-dentista en el abordaje del queratoquiste odontogénico, pues presenta la menor tasa de morbilidad y recidiva dentro de los patrones mostrados en la literatura(AU)

An Update of Gorlin-Goltz Syndrome.

Gorlin-Goltz syndrome encompasses a variety of clinical signs and symptoms including important oral manifestations which general dental practitioners should be aware of. In light of the risk of malignancy it is important to be aware of this syndrome and recognise the need for early referral for multidisciplinary management. This paper aims to discuss Gorlin-Goltz syndrome, the pathophysiology of the condition and address the wide range of clinical manifestations. The author will pay particular attention to the oral manifestations of the condition and the management of such anomalies.

Distraction Sugosteogenesis: Its Biologic Bases and Therapeutic Principles.

PURPOSE: Recently, the terms sugosteogenesis and distraction sugosteogenesis have been introduced to the scientific literature. While the former describes a biologic phenomenon, the latter refers to the clinical technique which relies on the accelerated normal bone healing process that takes place at the osseous walls surrounding a cystic cavity when active negative pressure is applied. The purpose of this study is to provide the biologic bases and the therapeutic principles of this emerging technique. Employing well-stablished biologic principles, clinical evidence from analogous techniques, emerging experimental data, and circumstantial evidence, this study presents the possible mechanism of action of the evacuator for odontogenic cysts (Evocyst), a closed, vacuum-like drain system intended to treat cystic conditions using negative pressure. METHODS: A review of the literature was done. Keywords for the Medline search were: marsupialization, decompression, odontogenic cysts, effects of negative pressure on bone, and negative pressure wound therapy. In addition, relevant publications from the reference list of the retrieved studies were considered. The matches were evaluated for relevance and analyzed accordingly. Clinical reports used to illustrate the concept of distraction sugosteogenesis were performed following the Declaration of Helsinki on medical protocol and ethics. RESULTS: Currently, the standard of care to manage odontogenic cystic lesions includes marsupialization, enucleation and curettage, decompression, and surgical resection. However, there is a need for an alternative option in which the entity could be treated while promoting bone formation. With large odontogenic cystic conditions treated in a short period of time, distraction sugosteogenesis appears to be a choice. CONCLUSION: The application of negative pressure to osseous cells produces a stretching that creates mechanical cues that trigger signaling pathways, promotes fluid flow, and enhances angiogenesis. All of them, combined, may explain sugosteogenesis. The clinical application of such parameters may explain the good clinical results obtained with the Evocyst.

Síndrome de Gorlin / Gorlin Syndrome

El síndrome de Gorlin es una enfermedad infrecuente de herencia autosómica dominante producida por mutaciones en genes de la vía de señalización Sonic Hedgehog, entre los que destaca PTCH1. Se caracteriza por el desarrollo de múltiples carcinomas basocelulares en edades tempranas, que pueden ir asociados a otras manifestaciones cutáneas como pits palmoplantares, o a manifestaciones extracutáneas, entre las que destacan los queratoquistes odontogénicos y el meduloblastoma. El papel del dermatólogo es importante en la sospecha de este síndrome, pero suele ser necesario un equipo multidisciplinar en el diagnóstico, seguimiento y en el tratamiento de estos pacientes. El tratamiento dermatológico puede ser complicado debido al alto número de carcinomas basocelulares y a su extensión. En los últimos años se han desarrollado nuevos fármacos que inhiben la vía Sonic Hedgehog y parecen prometedores para estos pacientes, aunque su eficacia está limitada por los efectos secundarios y la creación de resistencias

Gorlin syndrome is a rare autosomal dominant disease caused by mutations in the sonic hedgehog signaling pathway. Of particular importance is the PTCH1 gene. The disease is characterized by the development of multiple basal cell carcinomas at young ages. These tumors may present with other skin manifestations such as palmoplantar pits and with extracutaneous manifestations such as odontogenic keratocysts and medulloblastoma. Although the dermatologist may be key for recognizing clinical suspicion of the syndrome, a multidisciplinary team is usually necessary for diagnosis, treatment, and follow-up. Skin treatment may be complicated due to the large number of basal cell carcinomas and the extent of involvement. In recent years, new drugs that inhibit targets in the sonic hedgehog pathway have been developed. Although these agents appear promising options for patients with Gorlin syndrome, their efficacy is limited by adverse effects and the development of resistance

Tetrad presentation of non-syndromic odontogenic keratocyst: An uphill diagnostic and therapeutic challenge.

Odontogenic keratocyst (OKC), in the last decade sceptically referred to as keratocystic odontogenic tumor (KCOT), is known for its subclinical extensive growth potential and significant rate of recurrences. Odontogenic keratocyst, being the third most common cystic lesion (10-20%) of the maxillofacial region, is often recognized as a sporadic lesion and is well-documented in the literature. Multiple presentation of these cysts over a lifetime is relatively uncommon and is usually seen in conjunction with nevoid basal cell carcinoma syndrome (NBCC), orofacial digital syndrome, Noonan syndrome, Ehlers-Danlos syndrome, Simpson-Golabi-Behmel syndrome, or other syndromes. The 'two-hit' hypothesis postulated by Knudson best explains this anomaly, wherein multiple OKCs associated with the syndromes arise as a consequence of the allelic loss in the patched (PTCH) gene, mapped to the long arm of chromosome 9q22.3-q31. A partial expression of the gene may result in multiple OKCs (5%) without any related syndromes. Though concurrent occurrence of non-syndromic multiple OKCs is a rare phenomenon, a handful of cases have been documented over the past few years. Adding to this, we report a case of multiple OKCs occurring synchronously and bilaterally in all 4 quadrants in non-syndromic, otherwise healthy persons, which could indicate a shift in trend.

Current concepts of oral and maxillofacial rehabilitation and treatment in aviation.

Aerospace medicine is the medical discipline responsible for assessing and conserving the health, safety, and performance of individuals involved in air and space travel. With the upward trend in airline travel, flight-related oral conditions requiring treatment have become a source of concern for aircrew members. Awareness and treatment of any potential physiological problems for these aircrews have always been critical components of aviation safety. In a flight situation, oral and maxillofacial problems may in fact become life-threatening clinical conditions. The unusual nature of aerospace medicine requires practitioners to have unique expertise. Special attention to aerospace medicine will open the way for professionals to develop and apply their skills and capabilities. Both dentists and aviators should be aware of the issues involved in aviation dentistry. This article presents the principles of prevention, treatment guidelines, and dental-related flight restrictions.

Recent trends in the treatment of benign odontogenic tumors.

PURPOSE OF REVIEW: The management of benign, locally aggressive odontogenic tumors, namely, keratocystic odontogenic tumors (KOTs) and ameloblastomas, can be challenging. The purpose of this article is to briefly summarize important features of these lesions and review recent trends in the literature regarding their treatment. RECENT FINDINGS: Currently, KOTs are frequently treated with a conservative approach consisting of enucleation and adjuvant decompression or local microablation with peripheral ostectomies, Carnoy's solution, or cryotherapy. Conversely, ameloblastomas generally require marginal or segmental resection followed by reconstruction using local bone regeneration techniques or vascularized osteocutaneous free flaps, respectively. Bone regeneration techniques have improved with the use of autogenous progenitor cells held in place by autogenous or alloplastic scaffolding. Esthetic results for free flap reconstruction have improved with the use of inconspicuous surgical approaches utilizing intraoral or rhytidectomy incisions. Molecular markers for both neoplasms are being investigated as potential targets for chemotherapeutic agents. SUMMARY: Excluding hamartomas (i.e., odontomas), KOTs and ameloblastomas are the most common benign odontogenic lesions. Their management is often complicated by their locally infiltrative behavior, responsible for high rates of recurrence. Simple enucleation or excision of these lesions has proven insufficient. When left untreated, these lesions are capable of causing severe disfigurement and loss of function. Knowledge regarding current best practices and potential future therapeutics is imperative to well treated and effective disease management.

Pediatric Odontogenic Cysts of the Jaws.

Odontogenic cysts represent a common form of pathology of the jaws, and the natural history, clinicopathologic findings, and appropriate management strategies are important to the oral and maxillofacial surgeon. Odontogenic cysts in the pediatric populations are important pathologic entities given their potential impact on the growth and development of the maxillofacial complex. Inappropriate management strategies can severely affect the form and function of the growing child. Categorizing pediatric odontogenic cysts into inflammatory or developmental causes provides a convenient way of conceptualizing these various entities and helps facilitate the appropriate diagnosis and the subsequent management.

Dental clearance unsuccesful: cleidocranial dysplasia diagnosed at a relief of pain clinic.

A 55-year-old woman presented to Whangarei Base Hospital Emergency Department with a mandibular swelling adjacent to her unerupted tooth 48. She had never had dental radiographs taken, having had a dental clearance 20 years earlier. She wore full dentures. A panoramic dental radiograph revealed 44 unerupted teeth. Based on the clinical, oral and radiographic examinations a diagnosis of cleidocranial dysplasia (CCD) was confirmed. The patient had not been diagnosed with CCD prior to her hospital visit. Treatment included staged extractions of superficial mandibular supernumeraries and enucleation of the mandibular cyst, attempting to avoid pathological fracture. This would be followed by a six-month review and then annually as required. The case outlines the value of dental radiography in dental practice. Little is known about the prevalence of CCD in New Zealand and this is an area where future research could be conducted.

Influência de parâmetros clínicos, radiográficos, cirúrgicos e histopatológicos na taxa de recidiva dos ceratocistos odontogênicos: uma análise retrospectiva de coorte / Influence of clinical-radiographic, surgical and histopathological parameters in recurrence rate of Odontogenic Keratocysts: a retrospective cohort analysis

Não existe, na literatura, um consenso sobre o protocolo ideal de tratamento do Ceratocisto Odontogênico (CO). Isso se deve a alguns fatores, dentre eles à falta de padronização adequada dos dados avaliados nos trabalhos científicos. Essa falha é, muitas vezes, inerente a estudos retrospectivos. O objetivo deste estudo é avaliar a influência de parâmetros clínicos, radiográficos, cirúrgicos e histopatológicos no índice de recidiva do CO. Como diferencial, foram selecionados casos tratados de maneira uniforme e detalhada, pelo mesmo cirurgião. O tratamento foi a enucleação associada à ostectomia periférica, precedida ou não por descompressão da lesão. A amostra (n=24) foi composta por pacientes, com uma média de idade de 32.1 anos, que se apresentaram para tratamento inicial de uma lesão única de CO. Quatorze lesões (58.4%) foram submetidas a descompressão prévia. O tempo médio de acompanhamento dos pacientes foi de 60.5 meses (DP=31.3). Oito indivíduos (33%) apresentaram recidiva dos Cos e o tempo médio para desenvolvimento da recidiva foi de 19 meses (DP=4.9). Todas as recidivas foram diagnosticadas nos dois primeiros anos de acompanhamento e estavam significativamente associadas com: 1) pobre resposta clínica à descompressão (p=0.027); 2) preservação de dentes com evidência radiográfica de envolvimento de lesão entre as raízes dentárias (p=0.009) e 3) presença de brotamento epitelial da camada basal com ou sem formação de ilhas epiteliais na cápsula fibrosa (p=0.019). Este estudo sugere que parâmetros clínicos, radiográficos e microscópicos podem influenciar a recidiva do CO e têm a possibilidade ser avaliados individualmente como guia terapêutico

There is no consensus, in the literature, regarding the best protocol of treatment of Odontogenic Keratocyst (OKC). This is due to several factors, including the lack of adequate standardization of data assessed in the studies. This failure is usually inherent to retrospective studies. The objective of this study is to evaluate the influence of clinical, radiographic, surgical and microscopic parameters in the relapse rate of the disease. The differential aspect is in the uniform and detailed treatment applied by the same surgeon in all cases. The treatment applied was the enucleation with peripheral ostectomy, preceded by lesion decompression or not. The sample (n=24) was composed of patients, with a mean age of 32.1 years, presenting for the management of one untreated OKCs. Fourteen lesions (58.4%) were submitted to previous decompression procedure. The mean follow-up time was 60.5 months (SD=31.3). Eight patients (33%) developed recurrent lesions and a mean of disease-free interval for recurrent lesions of 19 months (SD=4.9). All recurrence lesions were diagnosed in two first years of follow-up and were significantly associated with: 1) poor clinical response to decompression (P=0.027); 2) remaining tooth with radiographic evidence of insinuation of the lesion between the dental roots (P=0.009); 3) presence of budding of the basal cells layer together with epithelial islands in the fibrous capsule (P=0.019). Our study suggests that these clinical, radiographic and microscopic parameters could affect relapse rate of patients with OKC and may individually guide the treatment choice

Interventions for the treatment of keratocystic odontogenic tumours.

BACKGROUND: The keratocystic odontogenic tumours (KCOTs) account for between about 2% and 11% of all jaw cysts and can occur at any age. They are more common in males than females with a male:female ratio of approximately 2:1. Although they are benign, KCOTs are locally very aggressive and have a tendency to recur after treatment. Reported recurrence rates range from 3% to 60%. The traditional method for the treatment of most KCOTs is surgical enucleation. However, due to the lining of the cyst being delicate and the fact that they frequently recur, this method alone is not sufficient. Adjunctive surgical treatment has been proposed in addition to the surgical enucleation, such as removal of the peripheral bone (ostectomy) or resection of the cyst with surrounding bone (en-bloc) resection. Other adjunctive treatments proposed are: cryotherapy (freezing) with liquid nitrogen and the use of the fixative Carnoy's solution placed in the cyst cavity after enucleation; both of which attempt to address residual tissue to prevent recurrence. OBJECTIVES: To assess the available evidence comparing the effectiveness of interventions for the treatment of KCOTs. SEARCH METHODS: We searched the following electronic databases: the Cochrane Oral Health Group Trials Register (to 17 March 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2015, Issue 2), MEDLINE via Ovid (1946 to 17 March 2015) and EMBASE via Ovid (1980 to 17 March 2015). We searched the US National Institutes of Health Trials Register (http://clinicaltrials.gov) and the WHO Clinical Trials Registry Platform for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases. SELECTION CRITERIA: Randomised controlled trials comparing one modality of intervention with another with or without adjunctive treatment for the treatment of KCOTs. Adults, over the age of 18 with a validated diagnosis of solitary KCOTs arising in the jaw bones of the maxilla or mandible. Patients with known Gorlin syndrome were to be excluded. DATA COLLECTION AND ANALYSIS: Review authors screened trials for inclusion. Full papers were obtained for relevant and potentially relevant trials. If data had been extracted, it would have been synthesised using the fixed-effect model, if substantial clinical diversity were identified between studies we planned to use the random-effects model with studies grouped by action provided there were four or more studies included in the meta-analysis, and we would have explored the heterogeneity between the included studies. MAIN RESULTS: No randomised controlled trials that met the inclusion criteria were identified. AUTHORS' CONCLUSIONS: There are no published randomised controlled trials relevant to this review question, therefore no conclusions could be reached about the effectiveness or otherwise of the interventions considered in this review. There is a need for well designed and conducted randomised controlled trials to evaluate treatments for KCOTs.

The keratocystic odontogenic tumour (KCOT)--an odyssey.

The most appropriate management for the lesion now known as the keratocystic odontogenic tumour (previously known as the odontogenic keratocyst) remains controversial. This article reviews the different management protocols adopted by one surgical unit over the last 30 years and the results obtained from the different treatment modalities. A current treatment protocol consisting of initial decompression followed by aggressive curettage and peripheral ostectomy with methylene blue staining appears to be successful, but our longest follow-up is only 6 years.

Inferior alveolar nerve function recovers after decompression of large mandibular cystic lesions.

OBJECTIVE: The treatment of large mandibular cystic lesions (diameter > 35 mm) is controversial. Few studies determine the inferior alveolar nerve function after decompression which is one of the major options for treating such lesions. We aim to investigate the recovery of inferior alveolar nerve function after decompression. METHODS: Twenty-two patients with large mandibular cystic lesions, diagnosed as keratocystic odontogenic tumor, ameloblastoma, or dentigerous cyst, were included. Inferior alveolar nerve function was observed by monitoring the pulp vitality of involved teeth (n = 64) with electric pulp test before decompression and 1, 3, 6, 9, 12, and 24 months after decompression, respectively. RESULTS: The pulp vitality of the involved teeth was significantly decreased before decompression. Recovery of pulp vitality could be observed after decompression, indicating the recovery of inferior alveolar nerve function. A majority (96.9%) of the vital pulp was preserved in the involved teeth after decompression. CONCLUSIONS: Recovery of inferior alveolar nerve function was remarkable in patients with large mandibular cystic lesions after decompression, indicated by the recovery of pulp vitality of involved teeth. When decompression is preferred, conservative therapy rather than root canal therapy is recommended for the teeth with root tip exposed in the cystic lesions and without pulposis.

Application of Ultrasonic Devices in Management of Periodontal Lesions - Bone Response in a Case of a Tooth with Poor Treatment Prognosis.

BACKGROUND: Surgical treatment of odontogenic jaw cysts may include one of the following four basic methods: enucleation, marsupialization, staged combination of marsupialization and enucleation, or enucleation with curettage. Enucleation/cystectomy, alone or combined with other procedures, is the preferred choice of treatment. OBJECTIVE: The aim of the case report was to present the outcome of an ultrasound-assistant periapical cystectomy in a frontal upper tooth with indications for extraction. RESULTS: Postoperative recovery was uneventful. The functional result was satisfactory. On the follow-up X-rays a reduction of the intraosseous defect by a new bone formation could be observed. CONCLUSION: We found ultrasonic surgery to be a promising approach for safe and effective odontogenic jaw cyst removal reducing the risk of its recurrence.