Development of a new preclinical model to study early implant loss: a validation study in the beagle dog.

OBJECTIVES: To develop a new preclinical model to study early implant loss, where local infection conditions would impair the implant osseointegration. MATERIALS AND METHODS: Forty-eight smooth, 2.9-mm diameter experimental implants were placed in the mandible of 8 beagle dogs (3 in each side). In half of the animals (test group, n = 24 implants), the implants received ligatures around the implant-abutment connection. In the other half, no ligatures were placed (control group, n = 24 implants). Four weeks later, implants were extracted in a flapless approach and standard 3.3-mm diameter SLActive implants were placed into the same osteotomy site without any further drilling. Eight weeks after the second implantation, animals were sacrificed and analyzed in terms of implant survival. RESULTS: After 8 weeks of healing, 4 implants were lost in the control group and 14 in the test group. This corresponded to a 17.4% of early implant loss in the control group and 58.3% in the test. Most of the early failures occurred within the first 5 weeks of healing. CONCLUSIONS: Implants placed in a pre-contaminated site present higher early loss than those placed in a non-contaminated site. This study represents a valid and robust preclinical model to study mechanisms and reduction of early implant loss as new technologies become available. CLINICAL RELEVANCE: Scientific rationale for the study: There is lack of animal models to study early implant loss. Thus, a proposal of a new model is presented. With the validation of this model, new technologies can be implemented to prevent early implant loss.

Unusual Presentation of Clear Cell Odontogenic Carcinoma: Case Report and Literature Review.

Clear cell odontogenic carcinoma (CCOC) is a rare, aggressive epithelial neoplasm of the jaw first described in 1985 by Hansen and classified as an odontogenic malignant tumor in the 2005 WHO classification. To date, only 117 cases have been reported in the literature written in English. In this paper, we report the atypical presentation of a pericoronal localized tumor in the right mandibular wisdom tooth discovered during a routine radiologic examination. The patient, a 44-year-old healthy female, was referred by her general dental practitioner for examination of temporomandibular dysfunction and recurrent myofascial pain. Anamnesis and clinical examination did not suggest tumoral disease. The osteolytic lesion was removed, and histological examination revealed a clear cell odontogenic tumor (CCOT) of the right posterior lower jaw. Segmental lower jaw resection was performed, and a free iliac crest bone transplant was fixed with mandibular reconstruction plate. No cervical neck dissection was needed. A five-year follow-up examination shows excellent local and systemic recovery and no sign of tumor recurrence. The patient still suffers from bruxism and myofascial related pain, which are treated conservatively with a Michigan splint and physiotherapy. Based on this additional case, we review the literature and discuss the challenging diagnostic aspects, the unusual clinical presentation, and the treatment of CCOC.

Type I Neurofibromatosis: Case Report and Review of the Literature Focused on Oral and Cutaneous Lesions.

Neurofibromatosis type 1 (NF1) is a common genetic disease whose dermatological lesions are at the forefront of its development. Cutaneous manifestations include café au lait spots, intertriginous freckling, and neurofibromas which appear during childhood and adolescence and are part of the clinical criteria to diagnose NF1. However, it is only recently that oral manifestations have been highlighted in many studies as frequently associated to NF1. This article aims to review oral and cutaneous manifestations related to NF1 and to report a case of a 51-year-old male with skin and oral neurofibromas related to NF1. Our patient presented with lesions on the gingiva, a rare localization that takes a hypertrophic form mimicking other various pathological conditions. Although not frequent, malignant transformation in NF1, especially regarding plexiform neurofibromas, is well established. Patients with NF1 therefore have regular follow-ups based on clinical examination, as sarcomatous transformation brings an extremely poor prognosis, recurrences and distant metastasis being common.

Association between maxillary sinus fungus ball and sinus bone grafting with deproteinized bovine bone substitutes: a case-control study.

OBJECTIVE: To evaluate the association between sinus bone graft and the development of fungus ball (FB) of the maxillary sinus. STUDY DESIGN: The charts of all patients seen for surgical treatment of maxillary sinus FB following sinus bone grafting between 2006 and 2014 were reviewed. The charts of 49 participants were selected from our internal registry for comparison as controls. The association between FB and age, gender, smoking habits, associated co-morbidities, and bone grafting material was evaluated. FB of the maxillary sinus was estimated by using an odds ratio with a Yates' correction. P values were computed using Fisher's exact test, and the statistical significance was set at a P value < .05. RESULTS: All 13 cases (100%) with FB of the maxillary sinus had received anorganic bovine bone as the bone substitute (P = .0001). There were significantly more women in the case group than in the control group (84.6% in the cases vs 40.8% in the controls; P = .01). CONCLUSIONS: This study demonstrated a significant association between a specific deproteinized bovine bone substitute use as sinus bone graft material and subsequent development of FB of the maxillary sinus.

Maxillary expansion using transpalatal distraction in patients with unilateral cleft lip and palate.

BACKGROUND: The goal of this study was to evaluate prospectively the use of a transpalatal distractor for surgically assisted rapid palatal distraction osteogenesis in the treatment of severe unilateral maxillary constriction of patients with cleft lip and palate following alveolar bone grafting. METHODS: The authors analyzed the clinical and radiographic data of eight patients with unilateral cleft lip and palate. Follow-up examinations were performed at 1, 3, 6, and 12 months. RESULTS: All of the patients had satisfactory palatal expansion and correction of the dental crossbite without major complications. None of the children in this study were noncompliant with the prescribed duration of the active distraction period. CONCLUSIONS: Surgically assisted rapid palatal distraction osteogenesis using a transpalatal distractor results in a high rate of success in correcting maxillary transverse width discrepancies and dental crossbite and offers a harmonious maxillary arch shape in patients with unilateral cleft lip and palate.

[Atypical surgical approach to the extraction of retained teeth]. / Atypische chirurgische Zugänge zur Entfernung retinierter Zähne.

Indication to extract deep impacted teeth as well as the surgical approaches is controversally discussed in the litterature. Based on a clinical case report we describe two atypical approaches, one is extraoral the other lingual for removing tow deeply impacted teeth. The revue of the litterature shows that atypical surgical approaches are only indicated in particular clinical situations. The indication to remove the teeth and the approach depends on the patient's compliance as well as the experience of the operator. In the reported case the extraoral approach is justified by the chronical dentogene infection with fistulisation and cutaneus changes in the submandibular region. Based on the much easier access to the tooth and the only minimal cutaneus modifications in this case, we recommand the extraoral approach for extraction of deep impacted teeth in some special cases like the one we present.