Microsoft Word - 82 2018.docx   Vol  6,  No  1  (2018)   ISSN  2167-­‐8677  (online)   DOI  10.5195/d3000.2018.82         http://dentistry3000.pitt.edu     New  articles  in  this  journal  are  licensed  under  a  Creative  Commons  Attribution  4.0  United  States  License.     This  journal  is  published  by  the  University  Library  System,  University  of  Pittsburgh  as  part  of  its  D-­‐Scribe  Digital  Publishing  Program  and  is  cosponored   by  the  University  of  Pittsburgh  Press.     Maximum  mouth  opening  in  healthy  children  and  adolescents  in             Istanbul   Mine  Koruyucu1,  Derya  Tabakcilar2,  Figen  Seymen1,  Koray  Gencay1     1Istanbul  University,  Faculty  of  Den6stry,  Department  of  Pedodon(cs,  Istanbul,  Turkey   2Yeditepe  University,  Faculty  of  Den7stry,  Department  of  Pedodon(cs,  Istanbul,  Turkey     Abstract   Objec&ves:  Mouth  opening  capacity  is  o0en  regarded  as  one  of  the  important  parameters  for  evalua7ng  the  func7on   of  the  temporomandibular  joint  (TMJ)  and  mas,catory  muscle  status.  A  reduced  mouth  opening  capacity  may  be  one   of  the  first  clinical  signs  of  TMJ  involvement.  The  purpose  of  this  study  was  to  create  age  related  percen;les  for  the   maximal  interincisal  distance  (MID)  of  healthy  children.  Methods:  The  pa'ents  admi.ed  for  rou'ne  dental  examina-­‐ !ons  to  Istanbul  University  Faculty  of  Den!stry,  Department  of  Pedodon!cs  were  included  in  this  study.  The  interin-­‐ cisal   measurements   were   performed   with   metallic   calliper   and   also   malocclusions  were   recorded   for   all   children.   Oneway  Anova  test,  Tukey  HDS  test,  Tamhane’s  T2  test  and  Student  t  test  were  used  for  sta;s;cal  analysis.  Results:   The  study  popula.on  comprised  of  1059  (569  males,  490  females),  3-­‐to  15-­‐year-­‐old  (mean  age  8.82±3.06)  children.   The  mean  score  of  maximal  inter-­‐incisal  distance  was  found  33.24±5.54  for  females;  33.32±5.71  for  males.  There  was   no  sta's'cally  significant  difference  according  to  gender  (p=0.815;  p>0.05).  The  mean  score  of  maximal   inter-­‐incisal   distance  was  found  28.63±4.34  for  3-­‐5  years;  33.52±4.84  for  6-­‐11  years;  37.35±5.52  for  12-­‐15  years  children.  Sta2s2-­‐ cally   significant   differences  were   found   between   age   groups   (p:   0.001;   p<0.01).  The  mean   score   of  maximal   inter-­‐ incisal  distance  was  found  32.9±5.6  for  class  I;  34.92±5.51  for  class  II;  35.2±5.36  for  class  III  malocclusions.  Sta:s:cally   significant   differences   were   found   between   malocclusion   groups   (p:0.001;   p<0.01).   Conclusion:   The   result   of   this   study  indicated  that  posi/ve  rela/onship  between  the  maximum  mouth  opening  and  age  and  malocclusion.     Cita%on:  Koruyucu  M,  et  al.  (2018)  Maximum   mouth  opening  in  healthy  children  and  adoles-­‐ cents  in  Istanbul.  Den$stry  3000.  1:a001   doi:10.5195/d3000.2018.82   Received:    December  11,  2017   Accepted:    February  21,  2018   Published:    July  13,  2018   Copyright:  ©2018  Koruyucu  M,  et  al.  This   is   an   open   access   ar!cle   licensed   under   a   Crea!ve   Commons   A"ribu%on   Work   4.0   United   States   License.   Email:  mine.yildirim@istanbul.edu.tr         Introduction   Palpation  of  muscle  and   joint,  occlusal  and  radiographic   examination  are  performed  for   assessment  of  mandibular  func-­‐ tion.  To  be  able  to  assess  tem-­‐ poromandibular  joint  (TMJ)  func-­‐ tion,  the  primary  value  to  be   known  is  how  much  joints  move   when  mouth  is  opened  fully  max-­‐ imum  mouth  opening  (MMO)   [1,2].    MMO  is  “  the  greatest  dis-­‐ tance  between  two  central  inci-­‐ sors  (maxillary  and  mandibular)  at   the  midline  when  measured  from   their  incisal  edges  during  the  pos-­‐ sible  wildest  opening  of  the   mouth”  according  to  many  re-­‐ searchers  [3,4].   Mouth  opening  limitation   may  be  associated  with  some  clin-­‐ ical  situations  like  temporoman-­‐ dibular  disorders,  odontogenic  in-­‐ fections,  oral  malignancies,  sub-­‐ mucous  fibrosis,  mandibular  frac-­‐ tures,  myopathies,  and  trauma  [5].     Sex,  age  and  height  have   an  impact  on  how  much  a  person   can  open  their  mouth.  As  an  im-­‐ portant  step,  before  diagnosing   that  a  person  is  suffering  from  lim-­‐ ited  mouth  opening,  it  is  necessary   to  acknowledge  normal  opening  of   the  population  [6].  Some  studies   researched  children  and  adoles-­‐ cents  MMO  values  among  differ-­‐ ent  populations  (Table  1)  [6–15].   Also,  most  of  these  studies  re-­‐ vealed  as  age  increases,  MMO  in-­‐ creases  as  well.  Moreover,  girls   have  a  decreased  MMO  compared   to  boys.  For  this  reason,  it  is  im-­‐ portant  to  define  normal  MMO   values  for  each  specific  popula-­‐ tion,  so  that  it  is  possible  to  diag-­‐ nose  whether  a  person  suffers   from  reduced  mouth  opening.   The  aim  of  this  study  was   to  evaluate  age  related  percentiles   for  the  maximal  inter-­‐incisal  dis-­‐ tance  of  healthy  children,  based   on  sex  and  malocclusion.         Maximum  mouth  opening  in  healthy  children  and  adolescents  in  Istanbul       Vol  6,  No  1  (2018)        DOI  10.5195/d3000.2018.82    http://dentistry3000.pitt.edu   Material  and  Methods   The  study  was  approved  by   the  Ethics  Committee  of  the  Istan-­‐ bul  University,  Medical  Faculty       (No:2013/105)  and  was  carried   out  in  agreement  with  the  Decla-­‐ ration  of  Helsinki  principles.  The   study  consisted  of  1059  Turkish   children  who  were  attending  to   Istanbul  University  Faculty  of  Den-­‐ tistry,  Clinics  of  Pedodontics,  for   routine  dental  examinations  in   2013.  569  boys  and  490  girls  be-­‐ tween  the  ages  of  between  3-­‐15   years  were  included.   Medical  and  dental  anam-­‐ nesis  was  taken  and  a  question-­‐ naire  filled  for  each  patient.  The   children  were  examined  by  one   experienced  pediatric  dentist   (MK).  They  were  positioned  in  a   way  that  they  would  stay  standing   up  and  were  soothed  to  be  com-­‐ fortable  by  the  dentist  by  support-­‐ ing  their  head.  The  MMO  meas-­‐ urement  was  recorded  by  measur-­‐ ing  the  maximum  distance  be-­‐ tween  the  incisal  edges  of  the   maxillary  central  incisor  and  man-­‐ dibular  central  incisor  at  the  mid-­‐ line  while  the  mouth  of  the  sub-­‐ ject  was  open  at  its  widest.    The   interincisal  measurements  were   performed  with  metallic  calliper   (Seitz  &  Haag  Munchner  Modell).   Inclusion  Criteria   This  study  includes  the  fol-­‐ lowing  criteria:  healthy  and  im-­‐ mobile  primary  maxillary  and   mandibular  central  incisors,  no   dental  trauma  history,  no  anterior   open-­‐bite,  no  caries  and  no  re-­‐ storative  materials  that  influenced   the  incisal  edges,  presence  of  fully   erupted  maxillary  and  mandibular   central  incisors  and  no  orthodon-­‐ tic  treatment  that  could  influence   the  position  of  the  central  incisors.   Exclusion  Criteria   The  exclusion  criteria  were   subjects  with  temporomandibular   disorders,  neurological  disorders,   craniofacial  deformities,  systemic   diseases  (juvenile  rheumatoid  ar-­‐ thritis),  congenital  abnormalities   and  neck  pain,  because  these   problems  might  cause  limited   mouth  opening  as  in  the  previous   cases  reported.     Statistical  analysis   All  statistical  analyses  were   performed  using  the  IBM  SPSS  Sta   Table  1.  Children  and  adolescent  MMO  values  from  different  studies.   Studies   Country   Age  Group   Sample  Size   MMO  (mm)   Rothenberg  [7]   USA   4-­‐14   189   43.99   Sousa  et  al.  [8]   Brazil   6-­‐14   303   43.79   Müller  et  al.  [9]   Switzerland   4-­‐17   20719   45   Kumar  et  al.  [6]   India   6-­‐8   8-­‐10   10-­‐12     856   45.95  (Girls),  46.04  (Boys)   47.27  (Girls),  48.53  (Boys)   52.05  (Girls),  52.38  (Boys)   Abou  Atme  et  al.  [10]   Lebanon   4-­‐15   102   45.8   Feteih  [11]   Saudi  Arabia   12-­‐16   385   46.5  (Girls),  50.2  (Boys)   Chen  et  al  [12]   Taiwan   3-­‐5   518   36.93  (Girls),  37.47  (Boys)     Benevides  et  al  [13]   Brasil   8-­‐12   181   49.06  (Girls),  49.59  (Boys)     Al-­‐Dlaigan  &  Asiry  [14]   Saudi  Arabia   12-­‐16   1825   35.5  (Girls),  43.5  (Boys)     Choi  [15]   Korea   2-­‐6   151   37.72  ±  5.10   Maximum  mouth  opening  in  healthy  children  and  adolescents  in  Istanbul       Vol  6,  No  1  (2018)        DOI  10.5195/d3000.2018.82    http://dentistry3000.pitt.edu   tistics  22  (IBM  SPSS,  Tur-­‐ key).  The  assumption  of  normal   distribution  was  confirmed  using   the  Shapiro  Wilk  test  and  MMO   was  found  appropriate  to  normal   distribution.  One-­‐way  ANOVA  fol-­‐ lowed  by  the  post  Tukey  HDS  and   Tamhane’s  T2  tests  were  used  to   examine  differences  in  MMO  rela-­‐ tive  to  sex  and  age  groups.  The   statistical  analyses  were  per-­‐ formed  using  the  Student’s  t-­‐test   for  independent  samples  of  males   and  females.  P  <  0.05  values  were   considered  statistically  significant.   Results   Descriptive  statistics  of  the   subjects  are  shown  in  Table  2.  The   study  population  comprised  of   1059  (569  males,  490  females),  3-­‐ to  15-­‐year-­‐old  (mean  age   8.82±3.06)  children.  The  MMO  in   relation  to  gender  and  age  is   shown  in  Table  2.  The  maximal   inter-­‐incisal  distance  was  observed   with  the  mean  score  of   33.24±5.54  for  the  female  group   and  33.32±5.71  for  the  male   group.  Statistically  significant  dif-­‐ ference  was  not  found  according   to  sex  (p=0.815;  p>0.05).  There   were  significant  rises  in  MMO  with   increasing  age,  regardless  of  sex.   The  highest  mean  MMO  according   to  age  was  in  those  aged  12-­‐15   years.  The  mean  score  of  maximal   inter-­‐incisal  distance  was  found   28.63±4.34  for  3-­‐5  years;   33.52±4.84  for  6-­‐11  years;   37.35±5.52  for  12-­‐15  years  chil-­‐ dren  (Table  2,  Figure  1,  Figure  2).   Statistically  significant  differences   were  found  between  age  groups   (p:  0.001;  p<0.01)  (Table  2).   The  maximal  inter-­‐incisal   distance  was  observed  with  the   mean  score  of  32.9±5.6  for  class  I;   34.92±5.51  for  class  II;  35.2±5.36   for  class  III  malocclusions  (Figure   3).  Statistically  significant  differ-­‐ ences  were  found  between  mal-­‐ occlusion  groups  (p:  0.001;   p<0.01)  (Table  2).   Discussion   MMO  has  been  described   as  the  inter-­‐  incisal  distance  or  as   overbite  added  inter-­‐incisal  dis-­‐ tance  [3,16–18].  To  measure   overbite  added  inter-­‐incisal  dis-­‐ tance,  the  distance  that  mandible   travels  vertically  should  be  meas-­‐ ured,  but,  as  pointed  out  by   Mezitis  et  al.  [16],  the  functional   opening  of  the  mouth  is  more  im-­‐ portant,  because  this  is  the  value   that  actually  affects  chewing  and   dental  treatment.  Therefore,  the   MMO  in  this  study  was  defined  as   Table  2.  Distribu(on  of  maximal  mouth  opening  according  to  gender,  age,  and  mal-­‐ occlusion.         Maximal  mouth  opening  (mm)   p   n  (%)   Mean  ±  SD   1Gender         Girls   490  (%46,3)   33,24  ±  5,54   0,815   Boys   569  (%53,7)   33,32  ±  5,71   2Age         3-­‐5  year   220  (%20,8)   28,63  ±  4,34   0,001**   6-­‐11  year   625  (%59,0)   33,52  ±  4,84   12-­‐15  year   214  (%20,2)   37,35  ±  5,52   2Malocclusion         Class  I   872  (%82,3)   32,9  ±  5,6   0,001**   Class  II   98  (%9,3)   34,92  ±  5,51   Class  III   89  (%8,4)   35,2  ±  5,36   1Student  t  Test       2Oneway  ANOVA                                          **p<0.01   Maximum  mouth  opening  in  healthy  children  and  adolescents  in  Istanbul       Vol  6,  No  1  (2018)        DOI  10.5195/d3000.2018.82    http://dentistry3000.pitt.edu   the  maximal  inter-­‐incisal  distance   (MID)  [5].   There  are  various  methods   to  measure  MMO  like  directly  by   using  a  calibrated  fiber  ruler   [9,14,19–21],  simple  ruler   [7,22,23],  scale  and  divider  [20],   vernier  caliper  or  wiley’s  bite   gauge  [12,13,24–26],  Boley  gauge   [27,28],  calibrated  Boley  gauge  [8],   modified  vernier  calliper  [6],  sub-­‐ ject’s  finger  [4,10],  optoelectric   jaw-­‐  tracking  system  [29,30],  Jaw   Motion  Analyzer  System  [31]  and   Therabite  range  of  motion  scales   [4,32].  Wood  and  Branco  [33]   compared  different  measurement   types  and  suggested  that  direct   measurements  using  a  ruler  or  cal-­‐ liper  were  more  accurate  and  pre-­‐ cise.  The  present  study  was  done   using  metallic  calliper.   The  most  important  factor   in  measuring  MMO  is  the  head   position  [30,34].  Higbie  et  al.  [34]   described  short-­‐term  alterations  in   head  position  have  a  significant   effect  on  the   amount  of  MMO  in   a  normal  popula-­‐ tion.  In  this  study,   all  subjects  were   placed  in  a  vertical   position  for  measur-­‐ ing  in  order  to  elim-­‐ inate  the  possible   influence  of  differ-­‐ ent  head  positions.   A  wide  range   of  MMO  has  been   reported  from  all   over  the  world  in   different  studies.   Studies  of  MMO   values  of  children  and  adolescents   from  different  countries  with  dif-­‐ ferent  age  range  are  described  in   Table  1.  We  could  not  compare   our  study  with  them  about  racial   differences  because  of  the  wide   age  range.  Longitudinal  studies  are   required  to  compare  racial  differ-­‐ ences  with  same  age.  The  only   study  done  on  Turkish  children  in   this  regard  [35];  TMJ  movements   were  examined  with  the  Tem-­‐ poromandibular  Opening  Index   (TOI)  and  its  own  formula  in  all   dentition  types   with  and  with-­‐ out  temporo-­‐ mandibular   joint  dysfunc-­‐ tion  syndrome.   TOI  showed   that  there   were  no  signifi-­‐ cant  differ-­‐ ences  between   different  denti-­‐ tions  or  genders.   Children  and  adolescents   do  not  grow  constantly  and  stably,   their  growth  show  different  phas-­‐ es  from  birth  to  adulthood.  Their   body  parts  do  not  develop  at  the   same  speed.    However,  some  stud-­‐ ies  have  shown  that  MMO  con-­‐ stantly  rises  after  birth  until  adult-­‐ hood,  and  then  gradually  decreas-­‐ es  during  aging.  Our  research  has   shown  that  MID  has  increased   with  age  among  the  subjects.  The-­‐ se  measurements  are  similar  to   reported  by  many  researchers  that   aged  among  3  to  15  [6– 10,14,15,27,31,32].  These  results   were  divergent  with  Rothenberg     [7],  Sousa  [8]  and  Ingervall  [36].   Age  may  be  an  important  predic-­‐ tor  of  MMO  measurements,  but   the  relationship  between  age  and   MMO  has  not  yet  been  estab-­‐ lished.  In  our  study,  mean  value  of   MMO  was  28,63  ±  4,34  mm  in   primary  dentition.  These  meas-­‐ urements  are  lower  from  to  the   ones  reported  by  Choi  et  al    [15].   Chen  et  al  [12]  and  Ying  et  al  [32]   among  two  to  six  year-­‐old  chil-­‐ dren.  The  mean  score  of  MMO   was  found  33.52±4.84  for  6-­‐11   years;  37.35±5.52  for  12-­‐15  years   Figure  1.  Scatterplot  of  the  correlation  between  inter-­‐ incisal  distance  and  age  of  all  children  (girls  and  boys).   Figure  2.  Mean  maximum  opening(mm)  by  age  groups.   Maximum  mouth  opening  in  healthy  children  and  adolescents  in  Istanbul       Vol  6,  No  1  (2018)        DOI  10.5195/d3000.2018.82    http://dentistry3000.pitt.edu   children.  These  measurements  are   lower  from  to  the  many  studies   [6–11,13–15,28].   There  was  no  statistically   significant  difference  of  MMO  ac-­‐ cording  to  gender  in  this  study.   These  results  were  compatible   with  many  studies  [6–10,32,37].   Only  few  researches  report  sex   difference  in  MMO  [7,24].  There-­‐ fore,  it  is  suggested  that  the  gen-­‐ der  effect  on  MMO  in  adults  is  not   observed  in  children  and  adoles-­‐ cents  because  of  they  have  in-­‐ complete  sexual  maturity.  Howev-­‐ er,  Ingervall  [36]  observed  MMO   values  of  10-­‐year  old  females  were   similar  to  the  adult  females;  but  it   was  not  similar  to  male  adults.   In  our  study,  the  mean   score  of  maximal  inter-­‐incisal  dis-­‐ tance  was  found  32.9±5.6  for  class   I;  34.92±5.51  for  class  II;  35.2±5.36   for  class  III  malocclusions.  Maloc-­‐ clusion  groups  showed  statistically   significant  differences.  We  hy-­‐ pothesized  like  Ying  [32],  that  a   Class  II  molar  relationship,  due  to   a  retrognathic  mandible,  would   demonstrate  a  smaller  MMO.  But   the  largest  MMO  value  was  ob-­‐ served  in  class  III   malocclusion.  We   thought  that  rea-­‐ son  of  this  situa-­‐ tion  was  our  study   contained  chil-­‐ dren  adolescents   who  have  not  yet   completed   growth.  But  Ying   et  al  [32]  found   occlusion  type   were  statistically   insignificant  in   affecting  MMO.  They  found  larg-­‐ est  MMO  value  at  class  II  in  left   molar  classification.   In  this  study,  we  estab-­‐ lished  basic  standard  values  of   MMO  in  Turkish  children  and  ado-­‐ lescents  for  detect  the  mandibular   and  TMJ  functions.  In  general,   MMO  was  lower  than  that 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