Coronectomy of impacted mandibular third molars: a clinical and radiological retrospective case series study with 2-9 years of follow-up.

BACKGROUND: Impacted mandibular third molars occasionally are in intimate relation to the inferior alveolar nerve (IAN). Coronectomy has been proposed as a good alternative to prevent injury of the IAN. The present study evaluates the clinical and radiological outcomes of impacted mandibular third molars presenting radiographic signs associated with a high risk of IAN injury, and which were treated with the coronectomy technique. MATERIAL AND METHODS: A retrospective case series evaluated the outcomes of coronectomies of impacted mandibular third molars. The inclusion criteria were: available preoperative, immediate postoperative and two-year panoramic radiographs, preoperative cone-beam computed tomography (CBCT), and a complete case history. The clinical evaluation comprised intraoperative complications (mobilized fragments of root and damage to adjacent structures), short-term complications (sensory alterations and postoperative infection), and long-term complications (infection or oral exposure). The IAN position with respect to the roots, root shape, eruption status, third molar position, radicular-complex migration and bone above roots were radiographically evaluated as well. RESULTS: Approximately a total of 2000 mandibular third molars were removed from 2011 to 2022. Of these, 39 molars in 34 patients were partially extracted using the coronectomy technique. The mean age was 36 years (range 22-77), and the mean follow-up was 28 months (range 24-84). There were two short-term postoperative infections. One of them was resolved through reintervention to remove the roots after antibiotic treatment, while the other required hospital admission and removal of the roots. One case of short-term transient lingual paresthesia was also recorded. Two long-term oral exposures were detected, and the root fragments had to be extracted. There were no permanent sensory alterations. CONCLUSIONS: In our case series of 39 impacted mandibular molars in intimate contact with the IAN and treated with the coronectomy technique, the number of complications was low (two infections and a single case of transient lingual paresthesia), and no permanent sensory alterations were observed. Prospective studies, especially randomized clinical trials, are needed to compare this technique with conventional extraction.

Fresado a bajas revoluciones sin irrigación versus fresado a altas revoluciones con irrigación para la preparación del lecho implantológico: una revisión bibliográfica de estudios clínicos / Low-speed drilling without irrigation versus high-speed drilling with irrigation for implant bed preparation: a literature review of clinical studies

El fresado a bajas revoluciones sin irrigación ha sido descrito como una técnica para la preparación del lecho implantológico. Diversas ventajas sobre el fresado convencional han sido reportadas, sin embargo, existe la sospecha de que el sobrecalentamiento óseo pueda afectar los parámetros clínicos relacionados con el implante dental. El objetivo de esta revisión fue evaluar las diferencias clínicas entre el fresado de baja velocidad sin irrigación y el fresado de alta velocidad con irrigación para la preparación del lecho implantológico. Un total de 124 artículos fueron encontrados y finalmente 9 artículos se incluyeron en la revisión. La evidencia científica actual muestra tasas de éxito y pérdida ósea marginal periimplantaria sin diferencias estadísticamente significativas entre las dos técnicas. Además, la mayor cantidad y las mejores características histomorfológicas y celulares del hueso recolectado mediante el fresado a bajas revoluciones sin irrigación suponen una ventaja a tener en cuenta. El calentamiento óseo se mantiene por debajo de la temperatura crítica para la osteonecrosis térmica en ambas técnicas. En conclusión, el fresado a bajas revoluciones sin irrigación puede considerarse una técnica segura y predecible tanto como el fresado convencional. Además, la obtención de hueso autólogo en mayor cantidad y con mejores características celulares pueden aportar al clínico un recurso eficaz para ciertas situaciones clínicas. Aunque se necesitan mayor número de estudios clínicos. (AU)

Low-speed drilling without irrigation has been described as a technique for preparing the implant bed. Different advantages over conventional drilling have been mentioned, however, the suspicion of bone overheating and therefore its possible affectation to the clinical parameters related to the dental implant. The aim of this review was to assess the clinical differences between low-speed drilling without irrigation and high-speed drilling with irrigation for implant site preparation. A total of 124 articles were found and finally 9 articles were included in the review. Current scientific evidence shows success rates and marginal peri-implant bone loss without statistically significant differences between the two techniques. In addition, the greater quantity and the better histomorphological and cellular characteristics of the bone collected by drilling at low revolutions without irrigation represent an advantage to be taken into account. Bone temperature is maintained below the critical temperature for thermal osteonecrosis for the both techniques. In conclusion, low-speed reaming without irrigation may require as much a safe and predictable technique as conventional reaming. In addition, obtaining autologous bone in greater quantities and with better cellular characteristics can provide the clinician with an effective resource for certain clinical situations. However, more clinical studies are needed. (AU)

Comparación histológica e inmunohistoquímica de la mucosa periimplantaria localizada alrededor de los pilares rectos estéticos convencionales y de los nuevos pilares slim: ensayo clínico multicéntrico aleatorizado a boca partida / Histological and immunohistochemical comparison of the peri-implant mucosa located around of conventional aesthetic straight abutments and the new slim abutments: clinical trial multicenter randomized split-mouth

Para garantizar el éxito de los implantes dentales, es necesario conseguir la formación de una adecuada mucosa periimplantaria que permita el rápido sellado biológico periimplantario, que es crucial para el éxito del implante, minimizando la capacidad invasiva de microorganismos a través del surco gingival. Por ello, la adhesión del epitelio y el tejido conectivo a la superficie de los pilares protéticos, es muy importante para la viabilidad de un implante dental. En este sentido, en los últimos años se ha modificado la morfología de los pilares protéticos, tanto a nivel del tamaño del cuerpo del pilar (diámetro), como en el cuello de estos, llegando incluso a incorporar surcos para mejorar la salud del tejido periimplantario. Sin embargo, el diseño de pilares estrechos cuyo diámetro a nivel de la conexión es menor que el de la plataforma del implante, comúnmente conocidos como platform switching (PS), parece ser el que mejor sellado mucoso proporcionaría al implante, al reducir el componente vertical del ancho biológico, y crear una mayor distancia horizontal. En la actualidad, el desconocimiento de cómo la modificación del diseño geométrico de un pilar protético, con un cambio en el diámetro del cuello tipo PS, puede influir en la formación de una adecuada mucosa periimplantaria; nos motivó al desarrollo de este proyecto de investigación. En el presente ensayo clínico, pretendemos comparar la composición, distribución y estructura de los tejidos peri-implantarios alrededor de los pilares protésicos intermedios con geometría axial recta (control) y cóncava del tipo PS (test) del fabricante Galimplant® (Galimplant S.L., Sarria, España). El objetivo es estudiar qué diseño de pilares obtiene un mejor sellado biológico desde el punto de vista clínico e histomorfométrico. (AU)

To guarantee the success of dental implants, it is necessary to achieve the formation of an adequate peri-implant mucosa that allows rapid peri-implant biological sealing, which is crucial for the success of the implant, minimizing the invasive capacity of microorganisms through the gingival sulcus. Therefore, the adhesion of the epithelium and connective tissue to the surface of the prosthetic abutments is very important for the viability of a dental implant. In this sense, in recent years the morphology of prosthetic abutments has been modified, both in terms of the size of the abutment body (diameter) and in the neck of these, even incorporating grooves to improve the health of the peri-implant tissue. However, the design of narrow pillars whose diameter at the connection level is less than that of the implant platform, commonly known as platform switching (PS), seems to be the one that would provide the best mucosal seal to the implant, by reducing the vertical component. of the biological width, and create a greater horizontal distance. At present, the lack of knowledge about how the modification of the geometric design of a prosthetic abutment, with a change in the diameter of the PS-type neck, can influence the formation of an adequate peri-implant mucosa; motivated us to develop this research project. In this clinical trial, we intend to compare the composition, distribution and structure of the peri-implant tissues around the intermediate prosthetic posts with straight (control) and concave axial geometry of the PS type (test) from the manufacturer Galimplant® (Galimplant S.L., Sarria, Spain). The objective is to study which abutment design obtains a better biological seal from the clinical and histomorphometric point of view. (AU)

Influence of root width and dentin wall thickness evaluated by endoscopy upon the outcome of periapical surgery. A cohort study.

BACKGROUND: An analysis was made of the correlation between root width, the thickness of the remaining dentinal wall as determined by endoscopy, and the outcome of periapical surgery. MATERIAL AND METHODS: A retrospective cohort study was carried out involving patients subjected to periapical surgery between 2017 and 2019 at the University of Valencia (Valencia, Spain). One year after surgery, cone-beam computed tomography (CBCT) was used to evaluate healing against the preoperative volumes. The maximum root width was measured on the postoperative CBCT scan at the apical section of the treated root. This measurement was transferred to the intraoperative endoscopic image, where the minimum root width, peripheral dentin thickness, and minimum dentin thickness were recorded. Root measurements, and the position (maxillary or mandibular) and type of tooth (roots of incisors, canines, premolars or molars) were further correlated to periapical surgery outcome. RESULTS: A total of 51 patients, comprising 52 teeth and 62 roots, were included in the study. The mean measurements were: maximum root width (4.13±0.84 mm), minimum root width (2.46±0.72 mm), peripheral dentin thickness (0.77±0.2 mm) and minimum dentin thickness (0.4±0.2 mm). The success rate was 82.2%. Premolar roots showed a greater minimum dentin thickness (0.58±0.25 mm) (p<0.003) than incisor roots. No significant association was found between the different measurements and the healing rate at one year, though the roots that failed to heal showed smaller minimum dentin thickness values than the roots that healed correctly. The position and type of tooth did not influence healing outcome. CONCLUSIONS: The root width and thickness of the remaining dentin wall did not significantly influence healing. However, the roots that failed to heal showed smaller minimum dentin thickness values than the roots that healed correctly.

Endoscopic findings in periapical surgery. A cross-sectional study of 206 roots.

BACKGROUND: A study is made of the findings of high-magnification rigid endoscopy at the root end surface following apicoectomy of teeth subjected to periapical surgery. MATERIAL AND METHODS: A cross-sectional study was made of patients subjected to periapical surgery at the Unit of Oral Surgery and Implantology (University of Valencia, Valencia, Spain) between 2011 and 2019. Following apicoectomy, the root end surfaces were inspected, with the evaluation of untreated canals, isthmuses, craze lines, crack lines, opaque dentin and gaps. Likewise, an analysis was made of the association between patient age and the tooth type and restoration and the presence of craze lines, cracks, opaque dentin and gaps. RESULTS: The final sample consisted of 168 patients subjected to periapical surgery, with 177 operated teeth and 206 roots. Untreated canals were observed in 14 roots (6.8%). Isthmuses were identified in 74 roots (35.9%), particularly in the mesial root of the lower first molar (94.1%). In turn, craze lines were identified in 8.3% of the roots, cracks in 3.9%, and gaps in 53.4%. The prevalence of opaque dentin was 78.3%, with a greater presence in posterior teeth (90.3% in premolars and 86.2% in molars) than in anterior teeth (50.6%) (p<0.001). Patient age and tooth restoration showed no correlation to the studied parameters. CONCLUSIONS: Craze lines and crack lines were observed in less than 10% of the roots, though opaque dentin was identified in 73% of the roots, particularly in posterior teeth, and gaps were found in over half of the canals.

Intraoral onlay block bone grafts versus cortical tenting technique on alveolar ridge augmentations: a systematic review.

BACKGROUND: To review systematically the bone gain and superficial resorption rate of the onlay block bone grafts versus the cortical tenting technique, as well as secondarily study the postoperative complications, implant survival and success rates, and peri-implant marginal bone loss. MATERIAL AND METHODS: Following the recommended methods for systematic reviews and meta-analyses (PRISMA), an electronic search was performed in the PubMed (MEDLINE), EMBASE and the Cochrane Library of the Cochrane Collaboration (CENTRAL) databases to identify all relevant articles published up to March 2021 on onlay block bone grafts and cortical tenting technique. RESULTS: Eighteen papers complied with the inclusion criteria. In onlay grafts, the vertical bone gain mean was 4.24 mm, and resorption 20.91%; and 4.29 mm in the horizontal augmentation with a resorption of 10.28%. The complication rate was 14.8%. The implant survival and success rates were 100% and 92%; and the mean peri-implant bone loss ranged from 0.6 to 1.26 mm. In cortical tenting technique, the vertical bone gain mean was 6.17 mm and the resorption of 9.99%; and 5.55 mm in the horizontal augmentation with a 6.12% of resorption. The complication rate was 24.6%. The implant survival and success rates were 96.63% and 100%; and the mean peri-implant bone loss ranged from 0.27 to 0.77mm. CONCLUSIONS: Despite the limitations, both techniques offer a predictable way to reconstruct atrophic alveolar ridges, though the cortical tenting technique seems to achieve a greater bone gain and a lower surface resorption. Current evidence is still limited due to the inadequate follow-up, lack of information referred to methodological quality and sample attrition.

Is periapical surgery follow-up with only two-dimensional radiographs reliable? A retrospective cohort type sensitivity study.

BACKGROUND: Two-dimensional (2D) radiographic techniques are commonly used for assessing lesion prognosis after endodontic surgery. The present retrospective cohort study analyzes the sensitivity and ability of different radiographic techniques in obtaining area and volume measurements of periapical lesions. MATERIAL AND METHODS: Preoperative and follow-up (6-48 months) periapical and panoramic radiographs (index test) and cone-beam computed tomography (CBCT) images (reference standard) were selected from an endodontic microsurgery database. Sensitivity was analyzed independently by two examiners. The areas of the 2D radiographic images and CBCT volumes were studied using Itk-Snap software and Romexis viewer. RESULTS: The sample comprised 105 patients and 105 teeth, with a mean follow-up of 21 months (range 6-48). Preoperatively, CBCT detected all the periapical areas, periapical radiography detected 67, and panoramic radiography detected 60. Postoperatively, of the 52 cases in which CBCT detected remains of the periapical area, periapical radiography detected 22, and panoramic radiography detected 17. The measurements of the areas obtained by the 2D methods, and the volumes obtained by CBCT, had to be transformed into linear measures for comparison purposes. The measurements were found to be significantly different in both the preoperative and the follow-up images. CONCLUSIONS:  Periapical radiography showed greater sensitivity than panoramic radiography, both preoperatively and at follow-up. The lesions measured with CBCT were larger, with significant differences than as evidenced by the periapical and panoramic radiographs.

Regeneración ósea guiada simultánea en implantes cigomáticos con una aproximación exteriorizada en una atrofia maxilar avanzada / Guided bone regeneration and zygomatic implants: a case report

Se presenta un caso clínico en el que se rehabilita a una paciente con maxilar superior atrófico mediante una combinación de implantes cigomáticos, colocados mediante una aproximación exteriorizada, e implantes anteriores convencionales palatinizados. Se realizó un procedimiento de regeneración ósea guiada alrededor de los implantes cigomáticos para obtener un mayor grosor de la cortical vestibular y palatina alrededor de los implantes del maxilar superior y mejorar el pronóstico. A un año de la carga protésica, el hueso periimplantario se mantiene estable

A clinical case is presented in which a patient with atrophic upper jaw is rehabilitated by a combination of zygomatic implants, placed using an exteriorized approach, and conventional palatalized anterior implants. A guided bone regeneration procedure is performed around the zygomatic implants to obtain a greater thickness of the facial bone and improve the prognosis. One year after loading, the peri-implant bone remains stable

Hemostatic agents in endodontic surgery of maxillary molars: A randomized controlled pilot study of polytetrafluoroethylene (PTFE) strips as an adjunct to epinephrine impregnated gauze versus aluminum chloride.

BACKGROUND: Hemostasis is of critical importance in endodontic surgery. Studies on bleeding control in maxillary molars are scarce. The present study compares the efficacy of two hemostatic techniques in controlling bleeding in endodontic surgery. MATERIAL AND METHODS: A randomized two-arm pilot study involving 30 patients with peri-radicular lesions in maxillary molars (first and second molars) was carried out including the following hemostatic agents: polytetrafluoroethylene (PTFE) strips as an adjunct to epinephrine impregnated gauze (test group; n = 15) and aluminum chloride (Expasyl™) (control; n = 15). Bleeding control was independently assessed by the surgeon and by two blinded observers before and after application of the hemostatic agent, and was classified as either adequate (complete bleeding control) or inadequate (incomplete bleeding control). RESULTS: Bleeding control was similar in both groups. Simple binary logistic regression analysis failed to identify variables affecting bleeding control. Only the height of the keratinized mucosal band (≥ 2 mm) suggested a decreased risk of inadequate bleeding control of up to 89% (OR=0.11; p=0.06). CONCLUSIONS: No difference in the efficacy of bleeding control was observed between PTFE strips as an adjunct to epinephrine impregnated gauze and aluminum chloride in maxillary molars.

Measurement of gap between abutment and fixture in dental conical connection implants. A focused ion beam SEM observation.

BACKGROUND: The aim of the authors was to examine the abutment-fixture interface in Morse-type conical implants in order to verify gaps at this level using a new microscopical approach. MATERIAL AND METHODS: In this in vitro study, 20 abutment-fixture complexes were prepared by sectioning (longitudinal and cross-sectional to the long axis) with a microtome and then with a focused ion beam (FIB). This is a micrometric machine tool that uses gallium ions to abrade circumscribed areas to dig deeper into the cuts obtained with the microtome in order to eliminate cut-induced artifacts. This is because the FIB abrasion is practically free from artifacts, which are normally generated by the action of the microtome blades or other techniques. Samples were then observed by scanning electron microscopy (SEM). RESULTS: The observation of the abraded parts with the FIB permitted measurement of the real gap between the implant-abutment components. A variable amount of gap was retrieved (from 0 to 3 µm) by the observations, confirming the non-hermetic nature of the connection. It has to be pointed out that in approximately 65% of cases, the gap accounted for less than 1 µm. CONCLUSIONS: The reported data confirmed that the analyzed connection system allowed for minimal gap. However, from the evidence of the present analysis, it cannot be assumed that the 2 parts of a Morse-type conical implant are fused in 1 piece, which would create a perfectly matched hermetic connection.

Patient morbidity after impacted third molar extraction with different flap designs. A systematic review and meta-analysis.

BACKGROUND: To review the literature on the effect of different surgical flaps upon patient morbidity (pain perception, trismus, swelling and osteitis) after impacted third molar extraction. MATERIAL AND METHODS: An electronic and complementary search of main databases and grey literature was performed up to January 2019 to retrieve randomized clinical trials. The Cochrane risk of bias assessment tool was used for methodological appraisal. A random-effects meta-analysis was conducted of pain perception and trismus. RESULTS: From the initially 1314 screened studies, only 11 were included in the qualitative synthesis, and 5 in the meta-analysis. There were no statistically significant differences in pain between the envelope and triangular flap designs over time, except on the sixth postoperative day, when the envelope flap proved more painful. Regarding trismus, statistically significant differences were observed on the seventh postoperative day, with greater mouth opening in the envelope flap group than in the triangular flap group. There were no clear differences in swelling and osteitis among the flap designs. CONCLUSIONS: Despite its limitations, the present meta-analysis found no clear differences in patient morbidity between the different flap designs.

Oral rehabilitation with dental implants in patients with recessive dystrophic epidermolysis bullosa: A retrospective study with 2-15 years of follow-up.

BACKGROUND: Epidermolysis bullosa (EB) comprises a group of hereditary disorders characterized by mechanical fragility of the skin and mucous membranes, with the development of blisters and vesicles in response to minimum tissue friction. Recessive dystrophic epidermolysis bullosa (RDEB) with generalized involvement is the most common subtype in the oral cavity. The present study was carried out to investigate dental implant survival, peri-implant tissue condition, patient satisfaction, and the impact of treatment upon the quality of life of patients with RDEB rehabilitated with implants and full-arch implant-supported prostheses. MATERIAL AND METHODS: Thirteen patients with RDEB underwent dental implant treatment between September 2005 and December 2016. A retrospective study was made to analyze implant survival, peri-implant tissue health and patient satisfaction. RESULTS: A total of 80 implants were placed (42 in the maxilla and 38 in the mandible) in 13 patients between 20-52 years of age and diagnosed with RDEB. All the implants were rehabilitated on a deferred basis with 20 full-arch prostheses. Fifteen fixed prostheses and 5 implant-supported overdentures were placed. The implant survival rate was 97.5% after a mean follow-up of 7.5 years after prosthetic loading. Fifty percent of the implants showed mucositis at the time of evaluation. Probing depth was maintained at 1-3 mm in 96.2% of the implants, and bleeding upon probing was observed in 67.5% of the implants. There was a high prevalence of bacterial plaque (85%). CONCLUSIONS: The treatment of edentulous patients with RDEB by means of implants and implant-supported prostheses is predictable as evidenced by the high success rate, and improves patient self-esteem and quality of life.

Association between maxillary sinus pathology and odontogenic lesions in patients evaluated by cone beam computed tomography. A systematic review and meta-analysis.

BACKGROUND: A study is made of the association between maxillary sinus pathology and odontogenic lesions in patients evaluated with cone beam computed tomography. MATERIAL AND METHODS: A literature search was made in five databases and OpenGrey. Methodological assessment was carried out using the Newcastle-Ottawa tool for observational studies. The random-effects model was used for the meta-analysis. RESULTS: Twenty-one studies were included in the qualitative review and 6 in the meta-analysis. Most presented moderate or low risk of bias. The periodontal disease showed to be associated with the thickening of the sinus membrane (TSM). Mucous retention cysts and opacities were reported in few studies. The presence of periapical lesions (PALs) was significantly associated to TSM (OR=2.43 (95%CI:1.71-3.46); I2=34.5%) and to odontogenic maxillary sinusitis (OMS) (OR=1.77 (95%CI: 1.20-2.61); I2=35.5%). CONCLUSIONS: The presence of PALs increases the probability of TSM and OMS up to 2.4-fold and 1.7-fold respectively. The risk differences suggests that about 58 and 37 of out every 100 maxillary sinuses having antral teeth with PALs are associated with an increased risk TSM and OMS respectively. The meta-evidence obtained in this study was of moderate certainty, and although the magnitude of the observed associations may vary, their direction in favor sinus disorders appearance, would not change as a result.

Impact of crestal and subcrestal implant placement upon changes in marginal peri-implant bone level. A systematic review.

BACKGROUND: To systematically assess studies analyzing peri-implant bone loss in implants placed in crestal and subcrestal position. MATERIAL AND METHODS: Following the recommended methods for systematic reviews and meta-analyses (PRISMA), an electronic search was conducted in the PubMed (MEDLINE), EMBASE and LILACS databases to identify all relevant articles published up until April 2017. The search included human studies comparing marginal bone loss (MBL) between a control group and a study group with a minimum of 10 patients and a minimum follow-up of 6 months after prosthetic loading with rough neck implants. Two independent reviewers assessed the risk of bias in the selected studies based on the Newcastle-Ottawa scale for observational studies and the Cochrane Collaboration for clinical trials. RESULTS: Of 342 potentially eligible items, 7 complied with the inclusion criteria. One article was retrieved through the manual search. Eight articles were finally included: five experimental and three observational studies. The risk of bias assessed by the Cochrane Collaboration and Newcastle-Ottawa showed a high risk of bias. The mean follow-up period was 21 months (range 6-36 months). In four studies, implants placed in a crestal position presented higher MBL than subcrestal implants - the differences being significant in one study, while in three studies, implants placed in a subcrestal position presented greater MBL than crestal implants, with significant differences in only one study. CONCLUSION: Despite its limitations, the present systematic review did not find better outcomes between crestal and subcrestal implant placement, however, new studies will be needed, involving improved designs and the standardization of protocols to allow statistical comparisons and the drawing of firm conclusions.

Volumetric variation of peri-implant soft tissues in convergent collar implants and crowns using the biologically oriented preparation technique (BOPT).

BACKGROUND: To evaluate the changes in the peri-implant soft tissues of convergent collar implants with biologically oriented preparation technique (BOPT) crowns, 10 months after loading. MATERIAL AND METHODS: A pilot study was carried out from January 2016 to October 2017 involving 14 patients with one or two implants in the posterior mandibular sector. A total of 32 convergent collar implants were placed using a non-submerged protocol. Three months later the provisional cemented crowns were fitted using the BOPT approach with the finish line 1-1.5 mm below the gingival margin, simulating coronal emergence of a natural tooth. The soft tissue changes were measured with an intraoral scanner at two different timepoints: a) on the day of provisionalization, before prosthetic loading; and b) 10 months later without the provisional prosthesis. The STL files were superimposed and the soft tissue changes were recorded using a color scale with measurement of the volumetric changes in mm3. RESULTS: A mean increase in peri-implant mucosal volume of 64.7 mm3 was observed in 29 implants. The zones with the greatest increase in soft tissue volume were the papillae of implants with adjacent teeth and the peri-implant buccal margin. Three implants showed a mean decrease in soft tissue volume of -25.1 mm3. CONCLUSIONS: The fitting and design of crowns using the biologically oriented preparation technique (BOPT) over convergent collar implants affords a significant increase in peri-implant soft tissue volume both at the level of the papillae and in the buccal margin.

Effect on osseointegration of two implant macro-designs:A histomorphometric analysis of bicortically installed implants in different topographic sites of rabbit's tibiae.

BACKGROUND: To evaluate the effect of two different implant macro-designs on the sequential osseointegration at bicortically installed implants in the rabbit tibia. A further aim is to compare the osseointegration at different topographic zones. MATERIAL AND METHODS: 27 New Zealand rabbits were implemented. Two implants, one for each macro-design (Ticare Inhex® or Ticare Quattro®, Mozo-Grau, Valladolid, Spain), were randomly implanted in the diaphysis or metaphysis of each tibia. The flaps were sutured to allow a submerged healing. The animals were sacrificed after 2, 4 or 8 weeks. Ground sections were prepared and analyzed. RESULTS: No statistically significant differences were found between the two groups for newly formed bone in contact with the implant surface, being about 16%, 19% and 33% in both groups, after 2, 4, and 8 weeks of healing. Bone apposition was slightly higher in the diaphysis, reaching values of 36.4% in the diaphysis, and 29.3% in the metaphysis at 8 weeks of healing. It was observed that the implant position showed a statistical significance regarding BIC values at 4 and 8 weeks (p<0.05). Multivariate analysis fails to detect statistical significant differences for the interaction between implant designs and topographic site. Ticare Quattro® design had a slight better BIC values at diaphysis sites across healing stages, but without reaching a statistical significance. CONCLUSIONS: The both implant macro-designs provided similar degrees of osseointegration. Bone morphometry and density may affect bone apposition onto the implant surface. The apposition rates were slightly better in diaphysis compared to metaphysis.

Salivary myeloperoxidase and malondialdehyde are increased in patients exhibiting an asymptomatic mandibular impacted third molar.

BACKGROUND: To determine whether saliva is a good means of evaluating concentrations of oxidative stress biomarkers, analyzing the correlation between concentrations in saliva and in follicular tissue, and to compare biomarker concentrations in patients with one asymptomatic mandibular impacted third molar (MITM) (before extraction) with a healthy control, and to determine how biomarkers are modified by extraction. MATERIAL AND METHODS: 80 patients with one asymptomatic MITM and 80 healthy controls were included. Saliva samples were collected from all subjects (before extraction in the study group) to evaluate Myeloperoxidase (MPO) and Malondialdehyde (MDA) concentrations. Follicular tissues were obtained during surgery to measure biomarkers. One month after extraction, saliva samples were collected to assess changes of oxidative stress. RESULTS: Salivary MPO and MDA showed positive correlation with concentrations in follicular tissue (MPO: correlation coefficient=0.72, p=0.025; MDA: =0.92, p=0.001). Patients with asymptomatic MITMs showed higher salivary concentrations of oxidative stress biomarkers than healthy control subjects, with statistical significance for both MPO (p<0.001) and MDA (p<0.001). One month after extraction, salivary biomarkers decreased significantly in the study group (p<0.001). CONCLUSIONS: Salivary MPO and MDA are higher among patients with one asymptomatic MITM, but these levels decrease significantly one month after surgical extraction. The large decrease in oxidative stress biomarkers could justify third molar extraction despite the absence of symptoms.

Relation between the distance from the cementoenamel junction to the bone crest and the thickness of the facial bone in anterior maxillary teeth: A cross-sectional tomographic study.

BACKGROUND: The purpose of this cross-sectional study was to evaluate radiologically, the relation between the distance from the cementoenamel junction (CEJ) to the facial bone crest (FBC), and the facial alveolar bone (FAB) width at maxillary anterior teeth. A further aim was to assess if the CEJ-FBC distance had an impact in the prevalence to find a FAB thickness greater than one mm. STUDY DESIGN: CBCT images were retrospectively obtained from the database of the Oral Surgery Unit of the University of Valencia. The teeth were divided in 3 groups according to the CEJ-FBC distance: Shorter (≤3mm), Middle (>3 ≤4.5 mm) and Larger (>4.5 mm). FAB thickness was measured by two different examiners at 1, 2 and 3 mm apical to the FBC. Normality of means were evaluated by Kolmogorov-Smirnov test and an ANOVA-type linear model was performed. RESULTS: 82 patients were included in the study, with 156 central incisors, 149 lateral incisors and 152 canines analyzed. A significant greater FAB thickness in Shorter (≤3mm CEJ-FBC) than Middle and Larger group was observed in all distances measured apical to the FBC. There was a significant inverse relation between the distance CEJ-FBC and FAB thickness at all distances measured. The prevalence of a FAB thickness equal or greater than one mm was 35.9% of all teeth analyzed from Shorter, 17.4% of Middle and 8.9% of Larger group at 1 mm apical to the FBC. CONCLUSIONS: When the distance from the CEJ to the FBC is augmented, thinner FAB thickness has to be expected in all teeth of the anterior maxilla. The prevalence to find a FAB thicker than one mm decreases as the distance from the FBC to the CEJ increases.

Simultaneous and delayed direct sinus lift versus conventional implants: Retrospective study with 5-years minimum follow-up.

BACKGROUND: To compare the radiological parameters and success of posterior maxillary direct sinus lift with simultaneous or delayed implant placement, or implant placement in native bone, after a minimum follow-up period of 5 years. MATERIAL AND METHODS: A retrospective cohort study was carried out in a university clinic, selecting patients subjected to implant treatment in the posterior maxilla between the years 2005 and 2011. The patients were divided into three groups: 1) implants placed in native bone; 2) direct sinus lift with simultaneous implant placement; and 3) direct sinus lift with delayed implant placement. Bone crest level, bone loss, vertical bone gain, and implant success and survival after a minimum follow-up period of 5 years after prosthetic loading were analyzed. RESULTS: A total of 163 patients and 329 implants were included in the study. The mean duration of follow-up was 7.0 ± 1.9 years. Bone loss and implant success and survival were very similar in all three groups, with no significant differences among them. Graft reabsorption was greatest during the first 12 months, though graft stabilization was confirmed after 5 years of follow-up. CONCLUSIONS: Bone loss and percentage success and survival proved very similar for the implants placed in native bone and for sinus lift with simultaneous or delayed implant placement. The height of the graft material decreased mainly in the first 12 months, and continued until stabilization after 5 years, with no significant variations thereafter.

Comparison of peri-implant bone loss between conventional drilling with irrigation versus low-speed drilling without irrigation.

BACKGROUND: To compare the technique of high speed drilling with irrigation and low speed drilling without irrigation in order to evaluate the success rate and peri-implant bone loss at 12 months of follow-up. MATERIAL AND METHODS: A randomized, controlled, parallel-group clinical trial was carried out in patients requiring dental implants to rehabilitate their unitary edentulism. Patients were recruited from the Oral Surgery Unit of the University of Valencia (Spain) between September 2014 and August 2015. Patients who met the inclusion criteria were randomized to two groups: group A (high-speed drilling with irrigation) and group B (low-speed drilling without irrigation). The success rate and peri-implant bone loss were recorded at 12 months of follow-up. RESULTS: Twenty-five patients (9 men and 16 women) with 30 implants were enrolled in the study: 15 implants in group A and 15 implants in group B. The mean bone loss of the implants in group A and group B was 0.83 ± 0.73 mm and 0.62 ± 0.70 mm, respectively (p> 0.05). In the maxilla, the bone loss was 1.04 ± 0.63 mm in group A and 0.71 ± 0.36 mm in group B (p> 0.05), while bone loss in the mandible was 0.59 ± 0.80 mm in group A and 0.69 ± 0.77 mm in group B (p> 0.05). The implant success rate at 12 months was 93.3% in group A and 100% in group B. CONCLUSIONS: Within the limitations of the study, the low-speed drilling technique presented peri-implant bone loss outcomes similar to those of the conventional drilling technique at 12 months of follow-up.