The Experts below are selected from a list of 318 Experts worldwide ranked by ideXlab platform

Leda A Francischone - One of the best experts on this subject based on the ideXlab platform.

  • cementum apical morphology and Hypercementosis a probable adaptive response of the periodontal support tissues and potential orthodontic implications
    Dental Press Journal of Orthodontics, 2012
    Co-Authors: Alberto Consolaro, Renata Bianco Consolaro, Leda A Francischone
    Abstract:

    Information about orthodontic movement of teeth with Hypercementosis is scarce. As cementum deposition continues to occur, cementum is expected to change the shape of the root and apex over time, but this has not yet been demonstrated. Nor has it ever been established whether it increases or decreases the prevalence of root resorption during orthodontic treatment. The unique biological function of the interconnected network of cementocytes may play a role in orthodontic movement and its associated root resorptions, but no research has ever been conducted on the topic. Unlike cementum thickness and Hypercementosis, root and apex shape has not yet been related to patient age. A study of the precise difference between increased cementum thickness and Hypercementosis is warranted. Hypercementosis refers to excessive cementum formation above and beyond the extent necessary to fulfill its normal functions, resulting in abnormal thickening with macroscopic changes in the tooth root, which may require the delivery of forces that are different from conventional mechanics in their intensity, direction and distribution. What are the unique features and specificities involved in moving teeth that present with Hypercementosis? Bodily movements would be expected to occur, since inclination might prove difficult to achieve, but would the root resorption index be higher or lower?

Frank Verstraete - One of the best experts on this subject based on the ideXlab platform.

  • Radiographic evaluation in clinical practice of the types and stage of incisor tooth resorption and Hypercementosis in horses.
    Equine veterinary journal, 2016
    Co-Authors: Travis J Henry, Sarah M. Puchalski, Boaz Arzi, Philip H. Kass, Frank Verstraete
    Abstract:

    SummaryBackground There are several reports of incisor tooth resorption and Hypercementosis in horses but to date studies have been limited in case numbers and to advanced lesions. Tooth resorption in other species is a radiographic diagnosis of types of resorption that are often identified before clinical signs. Our goal was to evaluate radiographically incisor tooth resorption in a large population of horses, utilising interpretation criteria from canine and human dentistry. Objective To document and classify incisor tooth resorption and Hypercementosis. Study design Retrospective descriptive case series. Methods Horses presented for routine dental care, >5 years old were included only if owners were unaware of incisor pathology. Radiographs (3 views) were obtained of the incisor teeth and incisor teeth resorption was classified according to the radiographic criteria described for humans and dogs. Hypercementosis and its location were recorded. Results Tooth resorption was detected in 149 of 169 (88.2%) horses and 951 of 1952 (48.7%) of incisor teeth. The classification system used was applicable in 926 (97.2%) of 951 affected teeth. Hypercementosis was detected in 34 (20.1%) horses and 148 (7.6%) teeth. As horses increased in age, resorption and Hypercementosis was more frequent; no significant differences were found among sex or breed categories. All horses with Hypercementosis had resorption, but only 23.4% of horses with resorption had Hypercementosis. Advanced (stage ≥3) resorption was detected in 159 (8.1%) teeth and 54 (32.0%) horses in an otherwise clinically healthy population. Main limitations Certain horses’ anatomy precluded isolation of the mandibular third incisor teeth from the canine teeth due to superimposition. Conclusions Incisor tooth resorption, in particular external replacement resorption and external inflammatory resorption, is common in horses. Hypercementosis is consistently associated with resorption but the inverse association is inconsistent. This article is protected by copyright. All rights reserved.

E.y. Chu - One of the best experts on this subject based on the ideXlab platform.

  • Reduced Orthodontic Tooth Movement in Enpp1 Mutant Mice with Hypercementosis.
    Journal of dental research, 2018
    Co-Authors: M. Wolf, M.b. Chavez, T.n. Kolli, K. Becker, E.y. Chu, A. Jäger, M.j. Somerman, Vivek Thumbigere-math, Brian L Foster
    Abstract:

    Previous studies revealed that cementum formation is tightly regulated by inorganic pyrophosphate (PPi), a mineralization inhibitor. Local PPi concentrations are determined by regulators, including ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1), which increases PPi concentrations by adenosine triphosphate hydrolysis. Orthodontic forces stimulate alveolar bone remodelling, leading to orthodontic tooth movement (OTM). To better understand how disturbed mineral metabolism and the resulting altered periodontal structures affect OTM, we employed Enpp1 mutant mice that feature reduced PPi and increased cervical cementum in a model of OTM induced by a stretched closed-coil spring ligated between the maxillary left first molar and maxillary incisors. We analyzed tooth movement, osteoclast/odontoclast response, and tooth root resorption by micro-computed tomography, histology, histomorphometry, and immunohistochemistry. Preoperatively, we noted an altered periodontium in Enpp1 mutant mice, with significantly increased periodontal ligament (PDL) volume and thickness, as well as increased PDL-bone/tooth root surface area, compared to wild-type (WT) controls. After 11 d of orthodontic treatment, Enpp1 mutant mice displayed 38% reduced tooth movement versus WT mice. Molar roots in Enpp1 mutant mice exhibited less change in PDL width in compression and tension zones compared to WT mice. Root resorption was noted in both groups with no difference in average depths, but resorption lacunae in Enpp1 mutant mice were almost entirely limited to cementum, with 150% increased cementum resorption and 92% decreased dentin resorption. Osteoclast/odontoclast cells were reduced by 64% in Enpp1 mutant mice, with a predominance of tartrate-resistant acid phosphatase (TRAP)-positive cells on root surfaces, compared to WT mice. Increased numbers of TRAP-positive cells on root surfaces were associated with robust immunolocalization of osteopontin (OPN) and receptor-activator of NF-κB ligand (RANKL). Collectively, reduced response to orthodontic forces, decreased tooth movement, and altered osteoclast/odontoclast distribution suggests Enpp1 loss of function has direct effects on clastic function/recruitment and/or indirect effects on periodontal remodeling via altered periodontal structure or tissue mineralization.

  • osteopontin regulates dentin and alveolar bone development and mineralization
    Bone, 2018
    Co-Authors: Brian L Foster, M.b. Chavez, T.n. Kolli, E.y. Chu, Cristiane R Salmon, A B Tran, Kamila Rosamilia Kantovitz, Manisha C Yadav, Sonoko Narisawa, Jose Luis Millan
    Abstract:

    Abstract The periodontal complex is essential for tooth attachment and function and includes the mineralized tissues, cementum and alveolar bone, separated by the unmineralized periodontal ligament (PDL). To gain insights into factors regulating cementum-PDL and bone-PDL borders and protecting against ectopic calcification within the PDL, we employed a proteomic approach to analyze PDL tissue from progressive ankylosis knock-out ( Ank −/− ) mice, featuring reduced PP i , rapid cementogenesis, and excessive acellular cementum. Using this approach, we identified the matrix protein osteopontin ( Spp1 /OPN) as an elevated factor of interest in Ank −/− mouse molar PDL. We studied the role of OPN in dental and periodontal development and function. During tooth development in wild-type (WT) mice, Spp1 mRNA was transiently expressed by cementoblasts and strongly by alveolar bone osteoblasts. Developmental analysis from 14 to 240 days postnatal (dpn) indicated normal histological structures in Spp1 −/− comparable to WT control mice. Microcomputed tomography (micro-CT) analysis at 30 and 90 dpn revealed significantly increased volumes and tissue mineral densities of Spp1 −/− mouse dentin and alveolar bone, while pulp and PDL volumes were decreased and tissue densities were increased. However, acellular cementum growth was unaltered in Spp1 −/− mice. Quantitative PCR of periodontal-derived mRNA failed to identify potential local compensators influencing cementum in Spp1 −/− vs. WT mice at 26 dpn. We genetically deleted Spp1 on the Ank −/− mouse background to determine whether increased Spp1 /OPN was regulating periodontal tissues when the PDL space is challenged by Hypercementosis in Ank −/− mice. Ank −/− ; Spp1 −/− double deficient mice did not exhibit greater Hypercementosis than that in Ank −/− mice. Based on these data, we conclude that OPN has a non-redundant role regulating formation and mineralization of dentin and bone, influences tissue properties of PDL and pulp, but does not control acellular cementum apposition. These findings may inform therapies targeted at controlling soft tissue calcification.

  • DS_10.1177_0022034518759295 – Supplemental material for Reduced Orthodontic Tooth Movement in Enpp1 Mutant Mice with Hypercementosis
    2018
    Co-Authors: M. Wolf, M.b. Chavez, T.n. Kolli, V. Thumbigere-math, K. Becker, E.y. Chu, A. Jäger, M.j. Somerman, B.l. Foster
    Abstract:

    Supplemental material, DS_10.1177_0022034518759295 for Reduced Orthodontic Tooth Movement in Enpp1 Mutant Mice with Hypercementosis by M. Wolf, M. Ao, M.B. Chavez, T.N. Kolli, V. Thumbigere-Math, K. Becker, E.Y. Chu, A. Jäger, M.J. Somerman, and B.L. Foster in Journal of Dental Research

  • Hypercementosis Associated with ENPP1 Mutations and GACI
    Journal of dental research, 2017
    Co-Authors: Vivek Thumbigere-math, M.b. Chavez, E.y. Chu, A Alqadi, N I Chalmers, Michael T. Collins, Carlos R. Ferreira, K Fitzgerald, Rachel I Gafni, William A. Gahl
    Abstract:

    Mineralization of bones and teeth is tightly regulated by levels of extracellular inorganic phosphate (Pi) and pyrophosphate (PPi). Three regulators that control pericellular concentrations of Pi and PPi include tissue-nonspecific alkaline phosphatase (TNAP), progressive ankylosis protein (ANK), and ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1). Inactivation of these factors results in mineralization disorders affecting teeth and their supporting structures. This study for the first time analyzed the effect of decreased PPi on dental development in individuals with generalized arterial calcification of infancy (GACI) due to loss-of-function mutations in the ENPP1 gene. Four of the 5 subjects reported a history of infraocclusion, overretained primary teeth, ankylosis, and/or slow orthodontic tooth movement, suggesting altered mineral metabolism contributing to disrupted tooth movement and exfoliation. All subjects had radiographic evidence of unusually protruding cervical root morphology in primary and/or secondary dentitions. High-resolution micro-computed tomography (micro-CT) analyses of extracted primary teeth from 3 GACI subjects revealed 4-fold increased cervical cementum thickness ( P = 0.00007) and a 23% increase in cementum density ( P = 0.009) compared to age-matched healthy control teeth. There were no differences in enamel and dentin densities between GACI and control teeth. Histology revealed dramatically expanded cervical cementum in GACI teeth, including cementocyte-like cells and unusual patterns of cementum resorption and repair. Micro-CT analysis of Enpp1 mutant mouse molars revealed 4-fold increased acellular cementum thickness ( P = 0.002) and 5-fold increased cementum volume ( P = 0.002), with no changes in enamel or dentin. Immunohistochemistry identified elevated ENPP1 expression in cementoblasts of human and mouse control teeth. Collectively, these findings reveal a novel dental phenotype in GACI and identify ENPP1 genetic mutations associated with Hypercementosis. The sensitivity of cementum to reduced PPi levels in both human and mouse teeth establishes this as a well-conserved and fundamental biological process directing cementogenesis across species (ClinicalTrials.gov NCT00369421).

M.b. Chavez - One of the best experts on this subject based on the ideXlab platform.

  • Reduced Orthodontic Tooth Movement in Enpp1 Mutant Mice with Hypercementosis.
    Journal of dental research, 2018
    Co-Authors: M. Wolf, M.b. Chavez, T.n. Kolli, K. Becker, E.y. Chu, A. Jäger, M.j. Somerman, Vivek Thumbigere-math, Brian L Foster
    Abstract:

    Previous studies revealed that cementum formation is tightly regulated by inorganic pyrophosphate (PPi), a mineralization inhibitor. Local PPi concentrations are determined by regulators, including ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1), which increases PPi concentrations by adenosine triphosphate hydrolysis. Orthodontic forces stimulate alveolar bone remodelling, leading to orthodontic tooth movement (OTM). To better understand how disturbed mineral metabolism and the resulting altered periodontal structures affect OTM, we employed Enpp1 mutant mice that feature reduced PPi and increased cervical cementum in a model of OTM induced by a stretched closed-coil spring ligated between the maxillary left first molar and maxillary incisors. We analyzed tooth movement, osteoclast/odontoclast response, and tooth root resorption by micro-computed tomography, histology, histomorphometry, and immunohistochemistry. Preoperatively, we noted an altered periodontium in Enpp1 mutant mice, with significantly increased periodontal ligament (PDL) volume and thickness, as well as increased PDL-bone/tooth root surface area, compared to wild-type (WT) controls. After 11 d of orthodontic treatment, Enpp1 mutant mice displayed 38% reduced tooth movement versus WT mice. Molar roots in Enpp1 mutant mice exhibited less change in PDL width in compression and tension zones compared to WT mice. Root resorption was noted in both groups with no difference in average depths, but resorption lacunae in Enpp1 mutant mice were almost entirely limited to cementum, with 150% increased cementum resorption and 92% decreased dentin resorption. Osteoclast/odontoclast cells were reduced by 64% in Enpp1 mutant mice, with a predominance of tartrate-resistant acid phosphatase (TRAP)-positive cells on root surfaces, compared to WT mice. Increased numbers of TRAP-positive cells on root surfaces were associated with robust immunolocalization of osteopontin (OPN) and receptor-activator of NF-κB ligand (RANKL). Collectively, reduced response to orthodontic forces, decreased tooth movement, and altered osteoclast/odontoclast distribution suggests Enpp1 loss of function has direct effects on clastic function/recruitment and/or indirect effects on periodontal remodeling via altered periodontal structure or tissue mineralization.

  • osteopontin regulates dentin and alveolar bone development and mineralization
    Bone, 2018
    Co-Authors: Brian L Foster, M.b. Chavez, T.n. Kolli, E.y. Chu, Cristiane R Salmon, A B Tran, Kamila Rosamilia Kantovitz, Manisha C Yadav, Sonoko Narisawa, Jose Luis Millan
    Abstract:

    Abstract The periodontal complex is essential for tooth attachment and function and includes the mineralized tissues, cementum and alveolar bone, separated by the unmineralized periodontal ligament (PDL). To gain insights into factors regulating cementum-PDL and bone-PDL borders and protecting against ectopic calcification within the PDL, we employed a proteomic approach to analyze PDL tissue from progressive ankylosis knock-out ( Ank −/− ) mice, featuring reduced PP i , rapid cementogenesis, and excessive acellular cementum. Using this approach, we identified the matrix protein osteopontin ( Spp1 /OPN) as an elevated factor of interest in Ank −/− mouse molar PDL. We studied the role of OPN in dental and periodontal development and function. During tooth development in wild-type (WT) mice, Spp1 mRNA was transiently expressed by cementoblasts and strongly by alveolar bone osteoblasts. Developmental analysis from 14 to 240 days postnatal (dpn) indicated normal histological structures in Spp1 −/− comparable to WT control mice. Microcomputed tomography (micro-CT) analysis at 30 and 90 dpn revealed significantly increased volumes and tissue mineral densities of Spp1 −/− mouse dentin and alveolar bone, while pulp and PDL volumes were decreased and tissue densities were increased. However, acellular cementum growth was unaltered in Spp1 −/− mice. Quantitative PCR of periodontal-derived mRNA failed to identify potential local compensators influencing cementum in Spp1 −/− vs. WT mice at 26 dpn. We genetically deleted Spp1 on the Ank −/− mouse background to determine whether increased Spp1 /OPN was regulating periodontal tissues when the PDL space is challenged by Hypercementosis in Ank −/− mice. Ank −/− ; Spp1 −/− double deficient mice did not exhibit greater Hypercementosis than that in Ank −/− mice. Based on these data, we conclude that OPN has a non-redundant role regulating formation and mineralization of dentin and bone, influences tissue properties of PDL and pulp, but does not control acellular cementum apposition. These findings may inform therapies targeted at controlling soft tissue calcification.

  • DS_10.1177_0022034518759295 – Supplemental material for Reduced Orthodontic Tooth Movement in Enpp1 Mutant Mice with Hypercementosis
    2018
    Co-Authors: M. Wolf, M.b. Chavez, T.n. Kolli, V. Thumbigere-math, K. Becker, E.y. Chu, A. Jäger, M.j. Somerman, B.l. Foster
    Abstract:

    Supplemental material, DS_10.1177_0022034518759295 for Reduced Orthodontic Tooth Movement in Enpp1 Mutant Mice with Hypercementosis by M. Wolf, M. Ao, M.B. Chavez, T.N. Kolli, V. Thumbigere-Math, K. Becker, E.Y. Chu, A. Jäger, M.J. Somerman, and B.L. Foster in Journal of Dental Research

  • Hypercementosis Associated with ENPP1 Mutations and GACI
    Journal of dental research, 2017
    Co-Authors: Vivek Thumbigere-math, M.b. Chavez, E.y. Chu, A Alqadi, N I Chalmers, Michael T. Collins, Carlos R. Ferreira, K Fitzgerald, Rachel I Gafni, William A. Gahl
    Abstract:

    Mineralization of bones and teeth is tightly regulated by levels of extracellular inorganic phosphate (Pi) and pyrophosphate (PPi). Three regulators that control pericellular concentrations of Pi and PPi include tissue-nonspecific alkaline phosphatase (TNAP), progressive ankylosis protein (ANK), and ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1). Inactivation of these factors results in mineralization disorders affecting teeth and their supporting structures. This study for the first time analyzed the effect of decreased PPi on dental development in individuals with generalized arterial calcification of infancy (GACI) due to loss-of-function mutations in the ENPP1 gene. Four of the 5 subjects reported a history of infraocclusion, overretained primary teeth, ankylosis, and/or slow orthodontic tooth movement, suggesting altered mineral metabolism contributing to disrupted tooth movement and exfoliation. All subjects had radiographic evidence of unusually protruding cervical root morphology in primary and/or secondary dentitions. High-resolution micro-computed tomography (micro-CT) analyses of extracted primary teeth from 3 GACI subjects revealed 4-fold increased cervical cementum thickness ( P = 0.00007) and a 23% increase in cementum density ( P = 0.009) compared to age-matched healthy control teeth. There were no differences in enamel and dentin densities between GACI and control teeth. Histology revealed dramatically expanded cervical cementum in GACI teeth, including cementocyte-like cells and unusual patterns of cementum resorption and repair. Micro-CT analysis of Enpp1 mutant mouse molars revealed 4-fold increased acellular cementum thickness ( P = 0.002) and 5-fold increased cementum volume ( P = 0.002), with no changes in enamel or dentin. Immunohistochemistry identified elevated ENPP1 expression in cementoblasts of human and mouse control teeth. Collectively, these findings reveal a novel dental phenotype in GACI and identify ENPP1 genetic mutations associated with Hypercementosis. The sensitivity of cementum to reduced PPi levels in both human and mouse teeth establishes this as a well-conserved and fundamental biological process directing cementogenesis across species (ClinicalTrials.gov NCT00369421).

M. Wolf - One of the best experts on this subject based on the ideXlab platform.

  • Reduced Orthodontic Tooth Movement in Enpp1 Mutant Mice with Hypercementosis.
    Journal of dental research, 2018
    Co-Authors: M. Wolf, M.b. Chavez, T.n. Kolli, K. Becker, E.y. Chu, A. Jäger, M.j. Somerman, Vivek Thumbigere-math, Brian L Foster
    Abstract:

    Previous studies revealed that cementum formation is tightly regulated by inorganic pyrophosphate (PPi), a mineralization inhibitor. Local PPi concentrations are determined by regulators, including ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1), which increases PPi concentrations by adenosine triphosphate hydrolysis. Orthodontic forces stimulate alveolar bone remodelling, leading to orthodontic tooth movement (OTM). To better understand how disturbed mineral metabolism and the resulting altered periodontal structures affect OTM, we employed Enpp1 mutant mice that feature reduced PPi and increased cervical cementum in a model of OTM induced by a stretched closed-coil spring ligated between the maxillary left first molar and maxillary incisors. We analyzed tooth movement, osteoclast/odontoclast response, and tooth root resorption by micro-computed tomography, histology, histomorphometry, and immunohistochemistry. Preoperatively, we noted an altered periodontium in Enpp1 mutant mice, with significantly increased periodontal ligament (PDL) volume and thickness, as well as increased PDL-bone/tooth root surface area, compared to wild-type (WT) controls. After 11 d of orthodontic treatment, Enpp1 mutant mice displayed 38% reduced tooth movement versus WT mice. Molar roots in Enpp1 mutant mice exhibited less change in PDL width in compression and tension zones compared to WT mice. Root resorption was noted in both groups with no difference in average depths, but resorption lacunae in Enpp1 mutant mice were almost entirely limited to cementum, with 150% increased cementum resorption and 92% decreased dentin resorption. Osteoclast/odontoclast cells were reduced by 64% in Enpp1 mutant mice, with a predominance of tartrate-resistant acid phosphatase (TRAP)-positive cells on root surfaces, compared to WT mice. Increased numbers of TRAP-positive cells on root surfaces were associated with robust immunolocalization of osteopontin (OPN) and receptor-activator of NF-κB ligand (RANKL). Collectively, reduced response to orthodontic forces, decreased tooth movement, and altered osteoclast/odontoclast distribution suggests Enpp1 loss of function has direct effects on clastic function/recruitment and/or indirect effects on periodontal remodeling via altered periodontal structure or tissue mineralization.

  • DS_10.1177_0022034518759295 – Supplemental material for Reduced Orthodontic Tooth Movement in Enpp1 Mutant Mice with Hypercementosis
    2018
    Co-Authors: M. Wolf, M.b. Chavez, T.n. Kolli, V. Thumbigere-math, K. Becker, E.y. Chu, A. Jäger, M.j. Somerman, B.l. Foster
    Abstract:

    Supplemental material, DS_10.1177_0022034518759295 for Reduced Orthodontic Tooth Movement in Enpp1 Mutant Mice with Hypercementosis by M. Wolf, M. Ao, M.B. Chavez, T.N. Kolli, V. Thumbigere-Math, K. Becker, E.Y. Chu, A. Jäger, M.J. Somerman, and B.L. Foster in Journal of Dental Research