José Luis Gutiérrez-Pérez

Inferior alveolar nerve paresthesia after overfilling of endodontic sealer into the mandibular canal.

The present study describes a case of endodontic sealer (AH Plus) penetration within and along the mandibular canal from the periapical zone of a lower second molar after endodontic treatment. The clinical manifestations comprised anesthesia of the left side of the lower lip, paresthesia and anesthesia of the gums in the third quadrant, and paresthesia and anesthesia of the left mental nerve, appearing immediately after endodontic treatment. The paresthesia and anesthesia of the lip and gums were seen to decrease, but the mental nerve paresthesia and anesthesia persisted after 3.5 years. This case illustrates the need to expend great care with all endodontic techniques when performing nonsurgical root canal therapy, especially when the root apices are in close proximity to vital anatomic structures such as the inferior alveolar canal.

Randomized, Double-Blind Study of Effectiveness of Intra-Alveolar Application of Chlorhexidine Gel in Reducing Incidence of Alveolar Osteitis and Bleeding Complications in Mandibular Third Molar Surgery in Patients With Bleeding Disorders

PURPOSE Chlorhexidine (CHX) is an antimicrobial agent used in the prevention of tooth decay, periodontal disease, and postextraction alveolar osteitis (AO). Recently, a bioadhesive gel to deliver the active substance, CHX, was introduced. The intra-alveolar placement of the bioadhesive gel allows a more direct and prolonged therapeutic effect of CHX, which is useful in the prevention of AO after extraction of impacted third molars. The intra-alveolar application of the bioadhesive CHX gel in patients with bleeding disorders may increase the risk of postoperative bleeding complications. Inversely, bleeding disorders might influence the efficacy of CHX for AO prevention. The purpose of the present study was to evaluate the effectiveness of the bioadhesive 0.2% CHX gel in reducing the incidence of impacted third molar postextraction AO in patients with bleeding disorders. MATERIALS AND METHODS We performed a double-blind, randomized, parallel-group study of 38 patients with bleeding disorders. The experimental group (n = 14) was treated with bioadhesive 0.2% CHX gel applied intraoperatively once after surgical removal of the third molar. The control group (n = 24) was treated in an identical fashion with placebo gel. RESULTS We observed a 57.15% reduction in the incidence of AO in the experimental group. The control group had a 17% incidence of AO and the experimental group had a 7% incidence of AO (P = .402). Bleeding complications occurred in 21% of the experimental group compared with 29% of the control group (P = .601). CONCLUSIONS As described in previous studies, the single intra-alveolar application of the bioadhesive 0.2% CHX gel in an intraoperative fashion seems to reduce the incidence of AO after removal of impacted third molars in patients with bleeding disorders. On the basis of the reported percentage of bleeding complications, the routine use of postoperative local hemostatic measures is recommended.

Pulp Revascularization of Immature Dog Teeth with Apical Periodontitis Using Triantibiotic Paste and Platelet-rich Plasma: A Radiographic Study

INTRODUCTION This study evaluates radiographically the efficacy of 4 revascularization protocols in necrotic-infected immature dog teeth with apical periodontitis (AP). METHODS Forty double-rooted immature premolar teeth from 4 female beagle dogs aged 5 months were used. Four teeth were left untouched as negative controls; the other 36 teeth were infected to develop pulp necrosis and AP following different treatment protocols. Four teeth were left untreated and assigned to the positive control group, and the last 28 teeth were randomly assigned into 4 experimental groups of 8 teeth: A1, sodium hypochlorite (NaOCl) + a blood clot; A2, NaOCl + platelet-rich plasma (PRP); B1, NaOCl + modified triantibiotic paste (mTAP) + a blood clot; and B2, NaOCl + mTAP + PRP. Teeth were monitored radiographically for 6 months regarding healing of periapical radiolucencies, thickening of the dentinal walls, and apical closure of roots. RESULTS Significant differences (P < .05) between the 4 groups were evident in the percentage of teeth showing improvement of periapical radiolucencies (62.5%), continued radiographic thickening of radicular walls (53.1%), radiographic apical closure (43.8%), and deposition of hard tissue on radicular dentin walls (53.1%). Group B2 showed maximal improvement in the 3 variables assessed (P < .05). Group A1 showed the minimum percentages in the 3 parameters assessed (P < .05). CONCLUSIONS These results suggest that an intracanal dressing of mTAP and the use of PRP as scaffold improves the success rate of the revascularization procedure.

Histologic characterization of regenerated tissues after pulp revascularization of immature dog teeth with apical periodontitis using tri-antibiotic paste and platelet-rich plasma

INTRODUCTION This study evaluates histologically the efficacy of 4 revascularization protocols in necrotic-infected immature dog teeth with apical periodontitis (AP). METHODS Forty double-rooted immature premolar teeth from 4 female Beagle dogs aged 5 months were used. Four teeth were left untouched as negative controls; the other 36 teeth were infected to develop pulp necrosis and AP. Four teeth were left untreated and assigned to the positive control group. The last 28 teeth were randomly assigned into four experimental groups of 8 teeth, each one treated with a different treatment protocol: A1, sodium hypochlorite (SH)+blood clot (BC); A2, SH+platelet-rich plasma (PRP); B1, SH+modified tri-antibiotic paste (mTAP)+BC; B2, SH+mTAP+PRP. The animals were sacrificed, histologic sections were prepared and three parameters were assessed: (1) presence or absence of new hard tissue on the internal root dentinal walls, (2) presence or absence of continued apical closure, and (3) presence or absence of vital tissue within the canal space. RESULTS Significant differences (p<0.05) between the four experimental groups were evident in the percentage of teeth showing histological apical closure (34.5%) and vital tissue within the canal space (68.8%). Group B2 showed the maximal improvement in the three variables assessed (p<0.05). Group A1 showed the minimum percentages in the three parameters assessed (p<0.05). CONCLUSIONS These results suggest that an intracanal dressing of mTAP, and the use of PRP as scaffold, improves the success rate of the revascularization procedure.

Long-term stability of surgical-orthodontic correction of class III malocclusions with long-face syndrome.

Objectives: In the first place, to evaluate skeletal changes of the maxilla and mandible induced by surgical-orthodontic correction of malocclusions class III with long-face syndrome and secondly, to analyze the stability of these skeletal changes in the long term (more than 6 years). Design of Study: A retrospective, unicentric and longitudinal study of 19 patients who had undergone surgical and orthodontic therapy for class III skeletal malocclusion with long-face syndrome was undertaken. A cephalometric analysis based on 8 angle measurements, and statistical analyses at three different points in time (before orthodontic treatment, after orthognathic surgery and after a retention period of at least 6 years) were carried out. Results: The changes produced following surgery show that, with the exception of the maxillary plane and the facial axis, all other variables presented changes of great statistical difference. Conclusions: Skeletal changes after orthodontic-surgical correction present maxillary advance, mandibular regression and mandibular anterorotation. The angles that represent the mandibular vertical position (ramus angle, goniac angle and mandibular plane angle) showed statistically significant relapses and no stability in contrast to the facial axis. Key words:Long term results, stability, relapse, orthognathic surgery, class III, long face.

Postoperative pain and swelling treatment protocol: A rational approach

One of the most important goals in oral surgery must be to reduce postsurgical symptoms following any surgical procedure. In order to obtain this objective it is very important to know the postoperative inflammation physiopathology. Scientific evidence has emphasized the importance of pre-emptive and preoperative treatment to control all the variables related with postoperative pain and swelling. The preventive philosophy must be associated with a rational use of analgesic and anti-inflammatory drugs. In this paper, based on the scientific evidence but also on our clinical experience, we review the different therapeutic measures that we can apply before, during and after the surgical procedure. We also describe a pharmacological protocol that is easily applicable in our offices in order to control postoperative symptoms.

Evaluation of apical preparations performed with ultrasonic diamond and stainless steel tips at different intensities using a scanning electron microscope in endodontic surgery

Objective: The objective of our study is to analyse (with the help of scanning electron microscopes) the quality of the dental root surface and the appearance of dental cracks after performing apical preparations using two diffe-rent types of ultrasonic tips. Study design: We used 32 single-rooted teeth that underwent a root canal and apical resection. Afterwards, the teeth were divided into 4 groups of 8 teeth each, with preparations of the apical cavities in the following manner: Group 1: stainless steel ultrasonic tip at 33KHz. Group 2: stainless steel ultrasonic tip at 30KHz. Group 3: diamond ultrasonic tip at 30KHz. Group 4: diamond ultrasonic tip at 33 KHz. The quality of the root surface and the presence of cracks were evaluated by one single observer using a scanning electron microscope. Results: All of the teeth in our study had cracks after the apical preparations. The mean number of cracks per tooth ranged between 6.1±1.9 (group 1) and 3.5±2.4 (group 4), with a significantly higher number found in the groups that used stainless steel tips (P=.03). The types of cracks produced involved: 8 complete cracks (4.5%), 167 incomplete cracks (94.4%), and 2 intradentinal cracks (1.1%), with no significant differences observed between the different frequencies used for each group. Conclusions: Stainless steel ultrasonic tips provoked a larger number of cracks than diamond tips. The frequency of vibration used did not have any effect on the number of cracks found. Key words:Apicoectomy, scanning electron microscope, therapeutic ultrasound, endodontic surgery, dentinal crack.

Comparison of masticatory efficacy among complete denture wearers with two adhesives and dentate individuals: A randomized, crossover, double-blind clinical trial

Statement of problem. The masticatory efficacy between dentate and edentulous individuals with and without the use of dental adhesives has been little studied. A comparative study of the addition of various agents of synthetic adhesion (vinyl methyl ether versus polyvinyl acetate) to these adhesives is needed. Purpose. The purpose of this randomized, crossover, double‐blind clinical trial was to compare the masticatory efficacy of wearers of complete dentures with and without dental adhesives of 2 different compositions and that of dentate controls. Material and methods. Seventeen participants with edentulism (edentulous control and 2 experimental groups) received new maxillary and mandibular complete dentures. After an adjustment period, they participated in masticatory tests with and without the use of 2 denture adhesives (Fittydent; Fittydent International GmbH and Corega; GlaxoSmithKline). The participants with edentulism were compared with 17 dentate controls. Masticatory efficacy was evaluated while the participants were masticating a substitute for irreversible hydrocolloid (20 g) and performing a single test of mastication (with 20 masticatory strokes) at 0, 7, and 14 days. Masticatory efficiency was measured immediately after each test with the sieving method and was calculated according to the weight of the particles of the substitute in each of the sieve filters. Data were analyzed using 1‐way ANOVA for simple pairs, and a multiple comparison was made using the Wilcoxon test with Bonferroni correction (&agr;=.05). Results. Significant differences were found between the 2 adhesives (P<.05) in the masticatory efficacy for filters 2 and 3, and nonsignificant differences occurred for filter 1. Compared with the edentulous control group, significant differences between the use or nonuse of adhesives were found in the edentulous group for the 3 filters (P<.05). Compared with the dentate control group, significant differences were found in masticatory efficiency between the dentate control group and the other groups for all comparisons (P<.05). Conclusions. Masticatory efficacy was higher with the use of Corega denture adhesive. The masticatory efficacy was significantly higher in dentate participants compared with participants with edentulism who had complete dentures, with or without denture adhesives. A significant increase of masticatory efficacy was observed among edentulous participants with denture adhesives in relation to those not using denture adhesives.

Confocal microscopy: A valid approach to evaluate the three-dimensional characteristics of root-end cavities

Objective: To analyze, using confocal microscope, the three-dimensional characteristics of the root-end cavity preparations completed in root apices of extracted teeth determining their area, perimeter, circularity and cavo-surface angle. Study design: Thirty-two single-rooted extracted teeth underwent endodontic treatment and apical resection. Root-end cavities were prepared according to 4 protocols, as follows: Group1, stainless steel ultrasonic tips (SST) at 33 KHz power; Group 2, SST at 30 KHz power; Group 3, diamond-coated ultrasonic tips (DCT) at 30 KHz power; and Group 4, DCT at 33 KHz power. Finally, root-end cavity was evaluated using a confocal microscope, recording its area, perimeter, circularity and cavo-surface angle. Results: The largest cavity perimeter was found in the Group 2 (4.8 ± 1.6 mm) (p & 0.05). Root-end cavities performed using SST showed larger areas than those performed with DCT (p = 0.03). The power of vibration or the tip type did not show correlation with the perimeter, circularity and cavo-surface angle of the root-end cavity (p & 0.05). Conclusions: Confocal microscopy is a useful approach to study the three-dimensional characteristics of the root-end cavity. Key words:Confocal microscopy, root-end cavity, surgical root canal treatment, ultrasonic tips.

Anatomic Analysis of the Maxillary Sinus: Preliminary Morphologic Comparison of Animal Models (Pig, Lamb, and Human).

A dvanced maxillary atrophy and associated sinus hyperpneumatization present major challenges to implant rehabilitation. The surgical procedure known as sinus lift or augmentation was developed in order to resolve this issue. Boyne and James in 1980, and later Tatum, in 1986, described this technique using a modified Caldwell-Luc approach, accessing the sinus through the lateral side, and detaching and lifting the Schneiderian membrane without damaging it so as to obtain more space for placing implants without contributing to damage to the membrane or maxillary sinus. Since then, several variations and modifications of this technique have been developed, with approaches through the alveolar ridge or atraumatic or closed lifts, with osteotomes. Over time, sinus lifts have become virtually routine surgical procedures and are frequently performed in dental practice, with a continuously increasing number of practicing oral surgeons. As with any other procedure, sinus lifts require practical training and a knowledge base. Animal models, serving as lowcost biologic models, have always been used for practicing surgical techniques. Authors have used several different animal models, including sheep, rabbits, goats, and monkeys. However, until now, very few studies have compared the anatomic morphology of different animal species in order to determine which is best for learning sinus lift techniques. The aim of this study was to determine whether sufficient anatomic similarity existed between lamb and pig animal models and which provided the strongest similarity to human anatomic structures in the maxillary sinus region in order to identify which model would serve best as a tool with which to learn the surgical sinus lift technique. We also sought to determine which animal model provides the strongest similarities to human anatomic structures in the maxillary sinus region. MATERIALS AND METHODS