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Premolar Area (premolar + area)

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Medical Sciences	100%

Selected Abstracts

The use of vein grafts in the repair of the inferior alveolar nerve following surgery

AUSTRALIAN DENTAL JOURNAL, Issue 2 2010
RHB Jones
Abstract Damage to the branches of the trigeminal nerve can occur as a result of a variety of causes. The most common damage to all divisions of this nerve occurs as a result of facial trauma. Unfortunately, iatrogenic damage to the inferior alveolar branch of the mandibular division of the trigeminal nerve is common because of its anatomical position within the mandible and its closeness to the teeth, particularly the third molar. It has been reported there is an incidence of approximately 0.5% of permanent damage to the inferior alveolar nerve following third molar removal. Extraction of other teeth within the mandible carries a lower incidence of permanent damage. However, damage can still occur in the premolar area, where the nerve exits the mandible via the mental foramen. Dental implants are a relatively new but increasing cause of damage to this nerve, particularly if the preoperative planning is inadequate. CT scanning is important for planning the placement of implants if this damage is to be reduced. Primary repair of the damaged nerve will offer the best chance of recovery. However, if there is a gap, and the nerve ends cannot be approximated without tension, a graft is required. Traditionally, nerve grafts have been used for this purpose but other conduits have also been used, including vein grafts. This article demonstrates the use of vein grafts in the reconstruction of the inferior dental branch of the mandibular division of the trigeminal nerve following injury, in this case due to difficulty in third molar removal, following sagittal split osteotomy and during the removal of a benign tumour from the mandible. In the five cases presented, this technique has demonstrated good success, with an acceptable return of function occurring in most patients. [source]

Alveolar ridge preservation with guided bone regeneration and a synthetic bone substitute or a bovine-derived xenograft: a randomized, controlled clinical trial

CLINICAL ORAL IMPLANTS RESEARCH, Issue 7 2010
Nikos Mardas
Abstract Objectives: The aim of this randomized, controlled clinical trial was to compare the potential of a synthetic bone substitute or a bovine-derived xenograft combined with a collagen membrane to preserve the alveolar ridge dimensions following tooth extraction. Methods: Twenty-seven patients were randomized into two treatment groups following single tooth extraction in the incisor, canine and premolar area. In the test group, the alveolar socket was grafted with Straumann Bone Ceramic® (SBC), while in the control group, Bio-Oss® deproteinized bovine bone mineral (DBBM) was applied. In both groups, a collagen barrier was used to cover the grafting material. Complete soft tissue coverage of the barriers was not achieved. After 8 months, during re-entry procedures and before implant placement, the horizontal and vertical dimensions of the residual ridge were re-evaluated and trephine biopsies were performed for histological analysis in all patients. Results: Twenty-six patients completed the study. The bucco-lingual dimension of the alveolar ridge decreased by 1.1±1 mm in the SBC group and by 2.1±1 in the DBBM group (P<0.05). Both materials preserved the mesio-distal bone height of the ridge. No differences in the width of buccal and palatal bone plate were observed between the two groups. The histological analysis showed new bone formation in the apical part of the biopsies, which, in some instances, was in direct contact with both SBC and DBBM particles. The coronal part of the biopsies was occupied by a dense fibrous connective tissue surrounding the SBC and DBBM particles. Conclusion: Both biomaterials partially preserved the width and the interproximal bone height of the alveolar ridge. To cite this article: Mardas N, Chadha V, Donos N. Alveolar ridge preservation with guided bone regeneration and a synthetic bone substitute or a bovine-derived xenograft: a randomized, controlled clinical trial. Clin. Oral Impl. Res. 21, 2010; 688,698. [source]

Pressure generated on a simulated oral analog by impression materials in custom trays of different designs

JOURNAL OF PROSTHODONTICS, Issue 3 2002
Radi Masri BDS
Purpose To measure the pressure exerted by maxillary edentulous impressions composed of 3 commonly used impression materials using four different impression tray configurations. Materials and Methods The study was performed using an oral analog that simulated an edentulous maxillary arch. Three pressure transducers were imbedded in the oral analog, 1 in the mid-palate area and the other 2 in the right and left ridge (maxillary first premolar areas). Custom trays of 4 different configurations were fabricated. The 3 impression materials tested were irreversible hydrocolloid, light-body and medium-body vinyl polysiloxane, and polysulfide. A total of 128 impressions were made. The custom tray and the oral analog were mounted using a reline jig. A Satec universal testing machine was used to apply a constant pressure of 2 kg/cm2 over a period of 5 minutes on the loaded custom tray. The pressure was recorded every 10 seconds. Factorial analysis of variance and Tukey's multiple comparison test were used to analyze the results. Results A significant difference in the pressure produced using different impression materials was found (p,0.001). Irreversible hydrocolloid and medium-body vinyl polysiloxane produced a significantly higher pressure than light-body vinyl polysiloxane and polysulfide impression materials. The presence of holes and/or relief did not significantly alter the magnitude of pressure. Conclusions All impression materials produced pressure during maxillary edentulous impression making. Tray modification was not important in changing the amount of pressure produced. The impression materials used had more effect on the pressure produced during impression making on the simulated oral analog. [source]

Early loading (2 or 6 weeks) of sandblasted and acid-etched (SLA) ITI® implants in the posterior mandible

CLINICAL ORAL IMPLANTS RESEARCH, Issue 2 2004
A 1-year randomized controlled clinical trial
Abstract: The aim of this 1-year prospective controlled clinical trial was to evaluate the effect of early loading of ITI® solid screw titanium implants with a sandblasted and acid-etched (SLA) surface on clinical and radiographic parameters. Material and methods: Twenty-seven consecutively admitted patients presenting bilateral edentulous posterior mandibular areas and in need of prosthetic reconstruction were recruited. Sixty-seven ITI® standard solid screw implants with an SLA surface, a diameter of 4.1 mm and a length of 8, 10 or 12 mm were installed bilaterally in molar and premolar areas according to a one-stage surgical protocol. One week (test) and 5 weeks (control) after implant placement, solid ITI® prosthetic abutments were connected using a torque of 35 N cm. No provisional restoration was fabricated. Two weeks (test) and 6 weeks (control) after implant placement, porcelain-fused-to-metal single-tooth crowns were cemented. Clinical measurements were obtained at day 0 and 2, 6, 12, 24 and 52 weeks thereafter. Periapical radiographs were taken immediately after implant placement, after 6 weeks and at the 1-year examination. Results: After 1 year, implant survival was 100%. Two test and one control implants rotated at the time of abutment connection and were left unloaded for 12 additional weeks. At the 1-year examination, no statistically significant differences were found between the test and control sites with respect to pocket probing depths (2.6 mm±0.5 vs. 2.7 mm±0.5), mean clinical attachment levels (3.1 mm±0.4 vs. 3.2 mm±0.5), mean percentages of sites bleeding on probing (9.7% vs. 8.3%), mean widths of keratinized mucosa (1.8 mm±0.4 vs. 1.9 mm±0.5), mean PerioTest® values (,1.4 PTV±0.9 vs. ,1.6 PTV±0.8) or mean crestal bone loss measurements (0.57 mm±0.49 vs. 0.72 mm±0.50). Conclusion: Based on these results, loading of titanium implants with an SLA surface as early as 2 weeks did not appear to jeopardize the osseointegration healing process in the posterior mandible. Furthermore, implants rotating at 35 N cm, if left unloaded for additional 12 weeks, did not negatively affect clinical and radiographic outcomes. Résumé Le but de cet essai clinique contrôlé prospectif d'une année a été d'évaluer l'effet de la mise en charge précoce d'implants en titane vis solide ITI® avec une surface sablée et mordancée (SLA) sur des paramètres cliniques et radiographiques. Vingt-sept patients présentant des aires bilatérales mandibulaires postérieures édentées et nécessitant donc une reconstruction prothétique ont été recrutés. Soixante-sept implants ITI® d'un diamètre de 4,1 mm et d'une longueur de 8, 10 ou 12 mm ont été placés bilatéralement dans les zones molaires et prémolaires suivant le processus chirurgical en une étape. Une semaine (test) et cinq semaines (contrôle) après leur placement des piliers prothétiques ITI® ont été serrés avec une force de 35 Ncm. Aucune restauration provisoire n'a été fabriquée. Deux semaines (test) et six semaines (contrôle) après le placement des implants des couronnes céramo-métalliques indépendantes ont été cimentées. Des mesures cliniques ont été obtenues aux jours 0 et deux, et aux semaines 6, 12, 24 et 52. Des radiographies périapicales ont été prises immédiatement après le placement des implants, après six semaines et une année. Après une année, le taux de survie implantaire était de 100%. Deux implants tests et un contrôle pivotaient au moment de la connexion du pilier et ont été laissés non-chargés pour 12 semaines supplémentaires. Après une année, aucune différence statistique n'a été trouvée entre les sites tests et contrôles en ce qui concerne les profondeurs de poches au sondage (2,6 ±0,5 mm vs 2,7± 0,5 mm), les niveaux d'attache clinique moyens (3,1±0,4 vs 3,2±0,5 mm,) les pourcentages moyens de sites saignant au sondage (9,7% vs 8,3%), les largeurs moyennes de muqueuse attachée (1,8±0,4 mm vs 1,9±0,5 mm), les valeurs Periotest moyennes (,1,4±0,9 PTV vs ,1,6 ±0,8 PTV) ou les mesures de perte osseuse crestale moyennes (0,57 ± 0,49 mm vs 0,72±0,52 mm). La charge d'implants en titane avec surface SLA aussitôt que deux semaines après leur placement ne semblait pas mettre en danger le processus d'ostéoïntégration dans la partie postérieure de la mandibule. De plus, les implants pivotant à 35 Ncm, si laissés non-chargés pour douze semaines supplémentaires, n'affectaient pas de manière négative les mesures cliniques et radiographiques. Zusammenfassung Material und Methoden: Es wurden siebenundzwanzig Patienten mit beidseits zahnlosem Seitenzahnbereich im Unterkiefer, welche eine prothetische Versorgung benötigten, in die Studie aufgenommen. Es wurden 67 ITI® Standard Vollschraubenimplantate mit einem Durchmesser von 4.1 mm und einer Länge von 8, 10 oder 12 mm beidseits in der Molaren- und Prämolarenregion transmukosal eingesetzt. Eine Woche (Test) und 5 Wochen (Kontrolle) nach Implantation wurden ITI® Massivsekundärteile mit einem Drehmoment von 35 Ncm eingesetzt. Es wurde keine provisorische Versorgung angefertigt. Zwei Wochen (Test) und 6 Wochen (Kontrolle) nach Implantation wurden Gold-Porzellan Einzelkronen einzementiert. Klinische Messungen wurden am Tag 0 und nach 2, 6, 12, 24, und 52 Wochen aufgenommen. Periapikale Röntgenaufnahmen wurden sofort nach der Implantation, nach 6 Wochen und anlässlich der 1 Jahreskontrolle angefertigt. Resultate: Nach einem Jahr betrug die Implanta-tüberlebensrate 100%. Zwei Test- und ein Kontrollimplantat drehten sich beim Einschrauben der Sekundärteile und wurden für zusätzliche 12 Wochen unbelastet belassen. Bei der 1 Jahresuntersuchung konnten zwischen Test- und Kontrolli-mplantaten keine statistisch signifikanten Unterschiede bezüglich Sondierungswerten (2.6mm+/,0.5 gegenüber 2.7mm +/,0.5), mittlerem klinischem Attachmentniveau (3.1mm +/,0.4 gegenüber 3.2mm +/,0.5), mittlerem Prozentanteil beim Bluten auf Sondieren (9.7% gegenüber 8.3%), mittlerer Breite der keratinisierten Mukosa (1.8mm +/,0.4 gegenüber 1.9mm +/,0.5), mittleren Periotest® Werten (,1.4 PTV +/,0.9 gegenüber ,1.6 PTV +/,0.8) oder mittlerem marginalem Knochenverlust (0.57mm +/,0.49 gegenüber 0.72mm +/,0.50) gefunden werden. Schlussfolgerung: Gemäss dieser Resultate schien die Belastung von Titanimplantaten mit SLA Oberfäche bereits nach 2 Wochen den Heilungsprozess der Osseointegration im posterioren Unterkiefer nicht zu beeinträchtigen. Implantate, die bei 35Ncm rotierten und daraufhin für weitere 12 Wochen unbelastet blieben, beeinflussten die klinischen und radiologischen Resultate nicht negativ. Resumen La intención de este ensayo clínico prospectivo controlado fue evaluar el efecto de una carga temprana sobre implantes macizos roscados de titanio con una superficie pulverizada con arena y gravada con ácido (SLA) sobre parámetros clínicos y radiográficos. Material y Métodos: Se reclutaron veintisiete pacientes consecutivamente admitidos que presentaron áreas edéntulas bilaterales en la mandíbula posterior y necesitando reconstrucción protésica. Se instalaron bilateralmente en las áreas molar y premolar sesenta y siete implantes ITI® estándar macizos roscados de titanio con una superficie SLA, un diámetro de 4.1 mm y una longitud de 8, 10 o 12 mm de acuerdo con un protocolo quirúrgico de una sola fase. Una semana (prueba) y 5 semanas (control) tras la colocación del implante, se conectaron pilares prostéticos macizos ITI usando un torque de 35 Ncm. No se fabricaron restauraciones provisionales. Dos semanas (prueba) y 6 semanas (control) tras la colocación de los implantes, se cementaron coronas unitarias metalocerámicas. Se obtuvieron medidas clínicas en el día 0 y tras 2, 6, 12, 24 y 52 semanas. Se tomaron radiografías periapicales inmediatamente tras la colocación del implante, a las 6 semanas y en el examen de 1 año. Resultados: Tras 1 año, la supervivencia de los implantes fue del 100%. Dos implantes de prueba y uno de control rotaron en el momento de la conexión del pilar y se dejaron sin carga durante 12 semanas más. En el examen de 1 año, no se encontraron diferencias significativas entre los lugares de prueba y los de control respecto a las profundidades de sondaje (2.6 mm±0.5 vs. 2.7 mm±0.5), niveles medios de inserción clínica (3.1±mm±0.4 vs. 3.2 mm±0.5), porcentaje medio de lugares con sangrado al sondaje (9.7% vs. 8.3%), anchura media de mucosa queratinizada (1.8 mm±0.4 vs. 1.9 mm±0.5), valores medios de Perio Test® (,1.4 PTV±0.9 vs. ,1.6 PTV±0.8) o a las medidas medias de perdida de hueso crestal (0.57 mm±0.49 vs. 0.72 mm±0.50). Conclusiones: Basándose en estos resultados, la carga de implantes de titanio con superficie SLA tan pronto como a las 2 semanas no pareció comprometer el proceso de cicatrización de la osteointegración en la mandíbula posterior. Mas aun, los implantes que rotaron a 35 Ncm, si se dejan sin carga durante 12 semanas más, no afectaron negativamente los resultados clínicos y radiográficos. [source]